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Sample records for growth factor-like mitogen

  1. Observations on human smooth muscle cell cultures from hyperplastic lesions of prosthetic bypass grafts: Production of a platelet-derived growth factor-like mitogen and expression of a gene for a platelet-derived growth factor receptor--a preliminary study

    Birinyi, L.K.; Warner, S.J.; Salomon, R.N.; Callow, A.D.; Libby, P.

    1989-01-01

    Prosthetic bypass grafts placed to the distal lower extremity often fail because of an occlusive tissue response in the perianastomotic region. The origin of the cells that comprise this occlusive lesion and the causes of the cellular proliferation are not known. To increase our understanding of this process we cultured cells from hyperplastic lesions obtained from patients at the time of reexploration for lower extremity graft failure, and we studied their identity and growth factor production in tissue culture. These cultures contain cells that express muscle-specific actin isoforms, shown by immunohistochemical staining, consistent with vascular smooth muscle origin. These cultures also released material that stimulated smooth muscle cell growth. A portion of this activity was similar to platelet-derived growth factor, since preincubation with antibody-to-human platelet-derived growth factor partially blocked the mitogenic effect of medium conditioned by human anastomotic hyperplastic cells. These conditioned media also contained material that competed with platelet-derived growth factor for its receptor, as measured in a radioreceptor assay. Northern blot analysis showed that these cells contain messenger RNA that encodes the A chain but not the B chain of platelet-derived growth factor. In addition, these cells contain messenger RNA that encodes a platelet-derived growth factor receptor. We conclude that cultured smooth muscle cells from human anastomotic hyperplastic lesions express genes for platelet-derived growth factor A chain and a platelet-derived growth factor receptor and secrete biologically active molecules similar to platelet-derived growth factor

  2. Heparin-binding epidermal growth factor-like growth factor promotes neuroblastoma differentiation.

    Gaviglio, Angela L; Knelson, Erik H; Blobe, Gerard C

    2017-05-01

    High-risk neuroblastoma is characterized by undifferentiated neuroblasts and low schwannian stroma content. The tumor stroma contributes to the suppression of tumor growth by releasing soluble factors that promote neuroblast differentiation. Here we identify heparin-binding epidermal growth factor-like growth factor (HBEGF) as a potent prodifferentiating factor in neuroblastoma. HBEGF mRNA expression is decreased in human neuroblastoma tumors compared with benign tumors, with loss correlating with decreased survival. HBEGF protein is expressed only in stromal compartments of human neuroblastoma specimens, with tissue from high-stage disease containing very little stroma or HBEGF expression. In 3 human neuroblastoma cell lines (SK-N-AS, SK-N-BE2, and SH-SY5Y), soluble HBEGF is sufficient to promote neuroblast differentiation and decrease proliferation. Heparan sulfate proteoglycans and heparin derivatives further enhance HBEGF-induced differentiation by forming a complex with the epidermal growth factor receptor, leading to activation of the ERK1/2 and STAT3 pathways and up-regulation of the inhibitor of DNA binding transcription factor. These data support a role for loss of HBEGF in the neuroblastoma tumor microenvironment in neuroblastoma pathogenesis.-Gaviglio, A. L., Knelson, E. H., Blobe, G. C. Heparin-binding epidermal growth factor-like growth factor promotes neuroblastoma differentiation. © FASEB.

  3. Overexpression of Heparin-Binding Epidermal Growth Factor-Like Growth Factor Mediates Liver Fibrosis in Transgenic Mice.

    Guo, Yongze; Ding, Qian; Chen, Lei; Ji, Chenguang; Hao, Huiyao; Wang, Jia; Qi, Wei; Xie, Xiaoli; Ma, Junji; Li, Aidi; Jiang, Xiaoyu; Li, Xiaotian; Jiang, Huiqing

    2017-08-01

    The role of heparin-binding epidermal growth factor-like growth factor (HB-EGF) in liver fibrosis is not clear and is sometimes even contradictory. To clarify this role, a HB-EGF transgenic (Tg) mouse model was, for the first time, used to evaluate the functions of HB-EGF in liver fibrosis. For the in vivo study, carbon tetrachloride injection and bile duct ligation treatment were used to induce liver fibrosis in HB-EGF Tg mice and wild-type (WT) mice, respectively. Primary hepatic satellite cells (HSCs) were isolated from HB-EGF Tg and WT mice for the in vitro study. Compared with the WT mice, HB-EGF Tg mice were shown to develop more severe liver fibrosis when treated with carbon tetrachloride or bile duct ligation, with increased matrix metalloproteinases 13 activity and enhanced expression of fibrogenic genes including α-smooth muscle actin and collagen I. HB-EGF gene transfer led to an increase in proliferation and a decrease in apoptosis in primary HSCs. The ERK signaling pathway was more highly activated in primary HSCs from HB-EGF Tg mice than in those from WT mice. Our investigation confirmed the profibrotic effect of HB-EGF on the liver using a Tg mouse model. This result may contribute to the elucidation of HB-EGF as a therapeutic target in liver fibrosis. Copyright © 2017 Southern Society for Clinical Investigation. Published by Elsevier Inc. All rights reserved.

  4. Epidermal growth factor-like domain 7 is a marker of the endothelial lineage and active angiogenesis.

    Bambino, Kathryn; Lacko, Lauretta A; Hajjar, Katherine A; Stuhlmann, Heidi

    2014-07-01

    Epidermal growth factor-like domain 7 (Egfl7) expression in the developing embryo is largely restricted to sites of mesodermal progenitors of angioblasts/hemangioblasts and the vascular endothelium. We hypothesize that Egfl7 marks the endothelial lineage during embryonic development, and can be used to define the emergence of endothelial progenitor cells, as well as to visualize newly-forming vasculature in the embryo and during the processes of physiologic and pathologic angiogenesis in the adult. We have generated a transgenic mouse strain that expresses enhanced green fluorescent protein (eGFP) under the control of a minimal Egfl7 regulatory sequence (Egfl7:eGFP). Expression of the transgene recapitulated that of endogenous Egfl7 at sites of vasculogenesis and angiogenesis in the allantois, yolk sac, and in the embryo proper. The transgene was not expressed in the quiescent endothelium of most adult organs. However, the uterus and ovary, which undergo vascular growth and remodeling throughout the estrus cycle, expressed high levels of Egfl7:eGFP. Importantly, expression of the Egfl7:eGFP transgene was induced in adult neovasculature. We also found that increased Egfl7 expression contributed to pathologic revascularization in the mouse retina. To our knowledge, this is the first mouse model that enables monitoring of endothelial cells at sites of active vasculogenesis and angiogenesis. This model also facilitated the isolation and characterization of EGFL7(+) endothelial cell populations by fluorescence activated cell sorting (FACS). Together, our results demonstrate that the Egfl7:eGFP reporter mouse is a valuable tool that can be used to elucidate the mechanisms by which blood vessels form during development and under pathologic circumstances. © 2014 Wiley Periodicals, Inc.

  5. Epidermal Growth Factor-like Domain 7 Predicts Response to First-Line Chemotherapy and Bevacizumab in Patients with Metastatic Colorectal Cancer

    Hansen, Torben Frøstrup; Nielsen, Boye Schnack; Sørensen, Flemming Brandt

    2014-01-01

    The number of approved antiangiogenic drugs is constantly growing and emphasizes the need for predictive biomarkers. The aim of this study was to analyze the predictive value of epidermal growth factor-like domain 7 (EGFL7) and microRNA-126 (miR126) to first-line chemotherapy combined with bevaci...

  6. Prognostic importance of circulating epidermal growth factor-like domain 7 in patients with metastatic colorectal cancer treated with chemotherapy and bevacizumab

    Hansen, Torben Frøstrup; Andersen, Rikke Fredslund; Aalund Olsen, Dorte

    2017-01-01

    High tumor expression of epidermal growth factor-like domain 7 (EGFL7) has been associated with a poor prognosis in colorectal cancer. The aim of the current study was to investigate the possible prognostic impact of circulating EGFL7 (cir-EGFL7), combined with single nucleotide polymorphism (SNP...

  7. Inhibition of the mitogenic response to platelet-derived growth factor by terbinafine

    St Denny, I.H.; Glinka, K.G.; Nemecek, G.M.; Stuetz, A.

    1987-01-01

    Terbinafine (T;(E)-N-(6,6-dimethyl-2-hepten-4-ynyl)-N-methyl-1-naphthalenemethanamine), an antimycotic which inhibits fungal squalene epoxidase activity, was examined for its effects on platelet-derived growth factor (PDGF)-stimulated mitogenesis. The inclusion of 1.5-5μM T in fibroblast incubation media was associated with increased [ 3 H]thymidine incorporation into DNA in the presence and absence of PDGF. However, T at concentrations above 6μM reduced DNA synthesis in control and PDGF-exposed cultures to nearly undetectable levels. Under a phase-contrast microscope, fibroblasts appeared morphologically normal at T concentrations as high as 25 μM. Neither the uptake of [ 3 H]thymidine nor the specific binding of 125 I-PDGF to fibroblast receptors was significantly affected by 10 μM T. Furthermore, concentrations of T which antagonized the mitogenic response to PDGF also interfered with fibroblast growth factor-induced mitogenesis. Together, these data suggest that T has the ability to inhibit the in vitro action of PDGF via a post-receptor mechanism

  8. Inhibition of the mitogenic response to platelet-derived growth factor by terbinafine

    St. Denny, I.H.; Glinka, K.G.; Nemecek, G.M. (Sandoz Research Institute, East Hanover, NJ (USA)); Stuetz, A. (Sandoz Forschungsinstitut, Vienna (Austria))

    1987-05-01

    Terbinafine (T;(E)-N-(6,6-dimethyl-2-hepten-4-ynyl)-N-methyl-1-naphthalenemethanamine), an antimycotic which inhibits fungal squalene epoxidase activity, was examined for its effects on platelet-derived growth factor (PDGF)-stimulated mitogenesis. The inclusion of 1.5-5{mu}M T in fibroblast incubation media was associated with increased ({sup 3}H)thymidine incorporation into DNA in the presence and absence of PDGF. However, T at concentrations above 6{mu}M reduced DNA synthesis in control and PDGF-exposed cultures to nearly undetectable levels. Under a phase-contrast microscope, fibroblasts appeared morphologically normal at T concentrations as high as 25 {mu}M. Neither the uptake of ({sup 3}H)thymidine nor the specific binding of {sup 125}I-PDGF to fibroblast receptors was significantly affected by 10 {mu}M T. Furthermore, concentrations of T which antagonized the mitogenic response to PDGF also interfered with fibroblast growth factor-induced mitogenesis. Together, these data suggest that T has the ability to inhibit the in vitro action of PDGF via a post-receptor mechanism.

  9. Differential expression of insulin like growth factor I and other fibroblast mitogens in porcine colostrum and milk

    Tan, T.J.; Simmen, R.C.M.; Simmen, F.A.

    1987-01-01

    Sow mammary secretions contain at least 3 distinct growth factor activities, distinguished by their size and relative abundance in colostrum or later milk. Gel filtration of colostrum in Sephadex G-200 columns, followed by acid-ethanol extraction and radioimmunoassay (RIA) for insulin like growth factor I (IGF-I) revealed high levels of this factor in the 150K and 50K MW regions, characteristic of IGF-I: binding protein complexes. Acid treatment of these fractions yielded free IGF-I peptide (7.5K). Parallel mitogen assays with a fibroblast cell line (AKR-2B) demonstrated a predominant peak of high MW activity (sow colostral growth factor-I, SCGF-I) eluting near the column void volume (MW > 150K). Treatment of SCGF-I with 1M acetic acid resulted in a size reduction of the mitogenic activity (MW < 10K), suggesting association of SCGF-I with a binding protein. The SCGF-I peptide was noncompetitive in IGF-I RIA, was distinct in MW from free IGF-I, and was not mitogenic for chick embryo fibroblasts. Sow milk contains less IGF-I and SCGF-I but does display a predominant peak of small MW (∼ 3K) AKR-2B activity. The changes in expression of these growth factors during lactation may reflect differing roles in lactogenesis and/or neonatal growth and development

  10. Subcellular distribution and mitogenic effect of basic fibroblast growth factor in mesenchymal uncommitted stem cells.

    Benavente, Claudia A; Sierralta, Walter D; Conget, Paulette A; Minguell, José J

    2003-06-01

    Uncommitted mesenchymal stem cells (MSC), upon commitment and differentiation give rise to several mature mesenchymal lineages. Although the involvement of specific growth factors, including FGF2, in the development of committed MSC is known, the effect of FGF2 on uncommitted progenitors remains unclear. We have analyzed on a comparative basis, the subcellular distribution and mitogenic effect of FGF2 in committed and uncommitted MSC prepared from human bone marrow. Indirect immunofluorescence studies showed strong nuclear FGF2 staining in both progenitors; however, cytoplasmic staining was only detected in committed cells. Western blot analysis revealed the presence of 22.5 and 21-22 kDa forms of FGF2 in the nucleus of both progenitors; however, their relative content was higher in uncommitted than in committed cells. Exogenous FGF2 stimulated proliferation and sustained quiescence in committed and uncommitted cells, respectively. These results show that both type of progenitors, apart from morphological and proliferative differences, display specific patterns of response to FGF2.

  11. Serum Heparin-binding Epidermal Growth Factor-like Growth Factor (HB-EGF) as a Biomarker for Primary Ovarian Cancer.

    Miyata, Kohei; Yotsumoto, Fusanori; Fukagawa, Satoshi; Kiyoshima, Chihiro; Ouk, Nam Sung; Urushiyama, Daichi; Ito, Tomohiro; Katsuda, Takahiro; Kurakazu, Masamitsu; Araki, Ryota; Sanui, Ayako; Miyahara, Daisuke; Murata, Masaharu; Shirota, Kyoko; Yagi, Hiroshi; Takono, Tadao; Kato, Kiyoko; Yaegashi, Nobuo; Akazawa, Kohei; Kuroki, Masahide; Yasunaga, Shin'ichiro; Miyamoto, Shingo

    2017-07-01

    Ovarian cancer is the most lethal malignancy among gynaecological cancers. Although many anticancer agents have been developed for the treatment of ovarian cancer, it continues to have an extremely poor prognosis. Heparin-binding epidermal growth factor-like grown factor (HB-EGF) has been reported to be a rational therapeutic target for ovarian cancer. Here, we evaluated the clinical significance of serum HB-EGF by examining the association between prognosis and serum HB-EGF levels in patients with primary ovarian cancer. We found that high serum HB-EGF concentrations were significantly associated with poor prognosis in a combined cohort of patients with all stages of ovarian cancer, as well as in a subset of patients with advanced disease. In addition, serum HB-EGF levels increased as the cancer advanced. These data suggest that serum HB-EGF may be a target for the design of novel therapies for ovarian cancer. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

  12. Recombinant epidermal growth factor-like domain-1 from coagulation factor VII functionalized iron oxide nanoparticles for targeted glioma magnetic resonance imaging.

    Liu, Heng; Chen, Xiao; Xue, Wei; Chu, Chengchao; Liu, Yu; Tong, Haipeng; Du, Xuesong; Xie, Tian; Liu, Gang; Zhang, Weiguo

    The highly infiltrative and invasive nature of glioma cells often leads to blurred tumor margins, resulting in incomplete tumor resection and tumor recurrence. Accurate detection and precise delineation of glioma help in preoperative delineation, surgical planning and survival prediction. In this study, recombinant epidermal growth factor-like domain-1, derived from human coagulation factor VII, was conjugated to iron oxide nanoparticles (IONPs) for targeted glioma magnetic resonance (MR) imaging. The synthesized EGF1-EGFP-IONPs exhibited excellent targeting ability toward tissue factor (TF)-positive U87MG cells and human umbilical vein endothelial cells in vitro, and demonstrated persistent and efficient MR contrast enhancement up to 12 h for preclinical glioma models with high targeting specificity in vivo. They hold great potential for clinical translation and developing targeted theranostics against brain glioma.

  13. Studies on binding and mitogenic effect of insulin and insulin-like growth factor I in glomerular mesangial cells

    Conti, F.G.; Striker, L.J.; Lesniak, M.A.; MacKay, K.; Roth, J.; Striker, G.E.

    1988-01-01

    The mesangial cells are actively involved in regulating glomerular hemodynamics. Their overlying endothelium is fenestrated; therefore, these cells are directly exposed to plasma substances, including hormones such as insulin and insulin-like growth factor I (IGF-I). These peptides may contribute to the mesangial sclerosis and cellular hyperplasia that characterize diabetic glomerulopathy. We report herein the characterization of the receptors and the mitogenic effects of IGF-I and insulin on mouse glomerular mesangial cells in culture. The IGF-I receptor was characterized on intact cells. The Kd of the IGF-I receptor was 1.47 X 10(-9) M, and the estimated number of sites was 64,000 receptors/cell. The binding was time, temperature, and pH dependent, and the receptor showed down-regulation after exposure to serum. The expression of the receptor did not change on cells at different densities. The specific binding for insulin was too low to allow characterization of the insulin receptor on intact cells. However, it was possible to identify the insulin receptor in a wheat germ agglutinin-purified preparation of solubilized mesangial cells. This receptor showed the characteristic features of the insulin receptor, including pH dependence of binding and a curvilinear Scatchard plot. The mitogenic effects of insulin and IGF-I on mesangial cells were measured by the incorporation of [3H]thymidine into DNA. IGF-I was more potent than insulin. The half-maximal response to IGF-I stimulation occurred at 1.3 X 10(-10) M, and a similar increase with insulin was observed at concentrations in the range of 10(-7) M, suggesting that this insulin action was mediated through the IGF-I receptor. These data show that the mouse microvascular smooth muscle cells of the glomerulus express a cell surface receptor for IGF-I in vitro and that this peptide is a potent mitogen for these mesangial cells

  14. Suppression of the Epidermal Growth Factor-like Domain 7 and Inhibition of Migration and Epithelial-Mesenchymal Transition in Human Pancreatic Cancer PANC-1 Cells.

    Wang, Yun-Liang; Dong, Feng-Lin; Yang, Jian; Li, Zhi; Zhi, Qiao-Ming; Zhao, Xin; Yang, Yong; Li, De-Chun; Shen, Xiao-Chun; Zhou, Jin

    2015-01-01

    Epidermal growth factor-like domain multiple 7 (EGFL7), a secreted protein specifically expressed by endothelial cells during embryogenesis, recently was identified as a critical gene in tumor metastasis. Epithelial-mesenchymal transition (EMT) was found to be closely related with tumor progression. Accordingly, it is important to investigate the migration and EMT change after knock-down of EGFL7 gene expression in human pancreatic cancer cells. EGFL7 expression was firstly testified in 4 pancreatic cancer cell lines by real-time polymerase chain reaction (Real-time PCR) and western blot, and the highest expression of EGFL7 was found in PANC-1 cell line. Then, PANC-1 cells transfected with small interference RNA (siRNA) of EGFL7 using plasmid vector were named si-PANC-1, while transfected with negative control plasmid vector were called NC-PANC-1. Transwell assay was used to analyze the migration of PANC-1 cells. Real-time PCR and western blotting were used to detect the expression change of EGFL7 gene, EMT markers like E-Cadherin, N-Cadherin, Vimentin, Fibronectin and transcription factors like snail, slug in PANC-1, NC- PANC-1, and si-PANC-1 cells, respectively. After successful plasmid transfection, EGFL7 gene were dramatically knock-down by RNA interference in si-PANC-1 group. Meanwhile, migration ability decreased significantly, compared with PANC-1 and NC-PANC-1 group. Meanwhile, the expression of epithelial phenotype marker E-Cadherin increased and that of mesenchymal phenotype markers N-Cadherin, Vimentin, Fibronectin dramatically decreased in si-PANC-1 group, indicating a reversion of EMT. Also, transcription factors snail and slug decreased significantly after RNA interference. Current study suggested that highly-expressed EGFL7 promotes migration of PANC-1 cells and acts through transcription factors snail and slug to induce EMT, and further study is needed to confirm this issue.

  15. MicroRNA-126 and epidermal growth factor-like domain 7-an angiogenic couple of importance in metastatic colorectal cancer. Results from the Nordic ACT trial.

    Hansen, T F; Christensen, R dP; Andersen, R F; Sørensen, F B; Johnsson, A; Jakobsen, A

    2013-09-03

    This study investigated the clinical importance of linked angiogenetic biomarkers to chemotherapy, combined with the anti-vascular endothelial growth factor A (anti-VEGF-A), as a first-line treatment in patients with metastatic colorectal cancer (mCRC). A total of 230 patients from a randomised phase III study were included. The primary microRNA-126 (pri-miRNA-126) A24G single-nucleotide polymorphism and the mature miRNA-126 were analysed by PCR using genomic DNA (full blood) and formalin-fixed paraffin-embedded tissue sections, respectively. The epidermal growth factor-like domain 7 (EGFL7) protein was visualised and quantified using immunohistochemistry. High tumour expression of miRNA-126 was significantly related to a longer progression-free survival. The independent prognostic value of miRNA-126 was confirmed using a Cox regression analysis (hazard ratio=0.49, 95% confidence interval=0.29-0.84, P=0.009). Although not significant, a relationship between EGFL7 expression and response rates is suggested, with EGFL7 expression at the invasive front being lower in responding patients than in the non-responders (P=0.063). The results validate the previous findings on the prognostic value of miRNA-126 in mCRC and may suggest a relationship between treatment efficacy and EGFL7 expression. As miRNA-126 may target VEGF-A as well as EGFL7, the results may provide predictive information in relation to next-generation anti-angiogenetics.

  16. Heparin-binding epidermal growth factor-like growth factor (HB-EGF) is increased in osteoarthritis and regulates chondrocyte catabolic and anabolic activities

    Long, D.L.; Ulici, V.; Chubinskaya, S.; Loeser, R.F.

    2015-01-01

    Objective We determined if the epidermal growth factor receptor ligand HB-EGF is produced in cartilage and if it regulates chondrocyte anabolic or catabolic activity. Methods HB-EGF expression was measured by quantitative PCR using RNA isolated from mouse knee joint tissues and from normal and OA human chondrocytes. Immunohistochemistry was performed on normal and OA human cartilage and meniscus sections. Cultured chondrocytes were treated with fibronectin fragments (FN-f) as a catabolic stimulus and osteogenic protein 1 (OP-1) as an anabolic stimulus. Effects of HB-EGF on cell signaling were analyzed by immunoblotting of selected signaling proteins. MMP-13 was measured in conditioned media, proteoglycan synthesis was measured by sulfate incorporation, and matrix gene expression by quantitative PCR. Results HB-EGF expression was increased in 12-month old mice at 8 weeks after surgery to induce OA and increased amounts of HB-EGF were noted in human articular cartilage from OA knees. FN-f stimulated chondrocyte HB-EGF expression and HB-EGF stimulated chondrocyte MMP-13 production. However, HB-EGF was not required for FN-f stimulation of MMP-13 production. HB-EGF activated the ERK and p38 MAP kinases and stimulated phosphorylation of Smad1 at an inhibitory serine site which was associated with inhibition of OP-1 mediated proteoglycan synthesis and reduced aggrecan (ACAN) but not COL2A1 expression. Conclusion HB-EGF is a new factor identified in OA cartilage that promotes chondrocyte catabolic activity while inhibiting anabolic activity suggesting it could contribute to the catabolic-anabolic imbalance seen in OA cartilage. PMID:25937027

  17. Activated platelet-derived growth factor β receptor and Ras-mitogen-activated protein kinase pathway in natural bovine urinary bladder carcinomas.

    Corteggio, Annunziata; Di Geronimo, Ornella; Roperto, Sante; Roperto, Franco; Borzacchiello, Giuseppe

    2012-03-01

    Bovine papillomavirus types 1 or 2 (BPV-1/2) are involved in the aetiopathogenesis of bovine urinary bladder cancer. BPV-1/2 E5 activates the platelet-derived growth factor β receptor (PDGFβR). The aim of this study was to analyse the Ras/mitogen-activated protein kinase (MAPK) pathway in relation to activation of PDGFβR in natural bovine urinary bladder carcinomas. Co-immunoprecipitation and Western blot analysis demonstrated that recruitment of growth factor receptor bound protein 2 (GRB-2) and Sos-1 to the activated PDGFβR was increased in carcinomas compared to normal tissues. Higher grade bovine urinary bladder carcinomas were associated with activation of Ras, but not with activation of downstream mitogen-activated protein kinase/extracellular signal-regulated kinase (Mek 1/2) or extracellular signal-regulated kinase (Erk 1/2). Copyright © 2011 Elsevier Ltd. All rights reserved.

  18. The cell-penetrating peptide domain from human heparin-binding epidermal growth factor-like growth factor (HB-EGF) has anti-inflammatory activity in vitro and in vivo

    Lee, Jue-Yeon; Seo, Yoo-Na; Park, Hyun-Jung; Park, Yoon-Jeong; Chung, Chong-Pyoung

    2012-01-01

    Highlights: ► HBP sequence identified from HB-EGF has cell penetration activity. ► HBP inhibits the NF-κB dependent inflammatory responses. ► HBP directly blocks phosphorylation and degradation of IκBα. ► HBP inhibits nuclear translocation of NF-κB p65 subunit. -- Abstract: A heparin-binding peptide (HBP) sequence from human heparin-binding epidermal growth factor-like growth factor (HB-EGF) was identified and was shown to exhibit cell penetration activity. This cell penetration induced an anti-inflammatory reaction in lipopolysaccharide (LPS)-treated RAW 264.7 macrophages. HBP penetrated the cell membrane during the 10 min treatment and reduced the LPS-induced production of nitric oxide (NO), inducible nitric oxide synthase (iNOS), and cytokines (TNF-α and IL-6) in a concentration-dependent manner. Additionally, HBP inhibited the LPS-induced upregulation of cytokines, including TNF-α and IL-6, and decreased the interstitial infiltration of polymorphonuclear leukocytes in a lung inflammation model. HBP inhibited NF-κB-dependent inflammatory responses by directly blocking the phosphorylation and degradation of IκBα and by subsequently inhibiting the nuclear translocation of the p65 subunit of NF-κB. Taken together, this novel HBP may be potentially useful candidate for anti-inflammatory treatments and can be combined with other drugs of interest to transport attached molecules into cells.

  19. Gene expression analysis of pig cumulus-oocyte complexes stimulated in vitro with follicle stimulating hormone or epidermal growth factor-like peptides

    Blaha, Milan; Němcová, Lucie; Vodičková Kepková, Kateřina; Vodička, P.; Procházka, Radek

    2015-01-01

    Roč. 13, č. 113 (2015) ISSN 1477-7827 R&D Projects: GA ČR GAP502/11/0593; GA MZe(CZ) QJ1510138 Institutional support: RVO:67985904 Keywords : FSH * growth factors * cumulus cell Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.147, year: 2015

  20. MicroRNA-126 and epidermal growth factor-like domain 7-an angiogenic couple of importance in metastatic colorectal cancer. Results from the Nordic ACT trial

    Hansen, T F; Christensen, René dePont; Andersen, R F

    2013-01-01

    Background:This study investigated the clinical importance of linked angiogenetic biomarkers to chemotherapy, combined with the anti-vascular endothelial growth factor A (anti-VEGF-A), as a first-line treatment in patients with metastatic colorectal cancer (mCRC).Methods:A total of 230 patients...... on the prognostic value of miRNA-126 in mCRC and may suggest a relationship between treatment efficacy and EGFL7 expression. As miRNA-126 may target VEGF-A as well as EGFL7, the results may provide predictive information in relation to next-generation anti-angiogenetics....

  1. MicroRNA-126 and epidermal growth factor-like domain 7-an angiogenic couple of importance in metastatic colorectal cancer. Results from the Nordic ACT trial

    Hansen, T F; Christensen, René dePont; Andersen, R F

    2013-01-01

    Background:This study investigated the clinical importance of linked angiogenetic biomarkers to chemotherapy, combined with the anti-vascular endothelial growth factor A (anti-VEGF-A), as a first-line treatment in patients with metastatic colorectal cancer (mCRC).Methods:A total of 230 patients......-like domain 7 (EGFL7) protein was visualised and quantified using immunohistochemistry.Results:High tumour expression of miRNA-126 was significantly related to a longer progression-free survival. The independent prognostic value of miRNA-126 was confirmed using a Cox regression analysis (hazard ratio=0.49, 95...... on the prognostic value of miRNA-126 in mCRC and may suggest a relationship between treatment efficacy and EGFL7 expression. As miRNA-126 may target VEGF-A as well as EGFL7, the results may provide predictive information in relation to next-generation anti-angiogenetics....

  2. Glucose, other secretagogues, and nerve growth factor stimulate mitogen-activated protein kinase in the insulin-secreting beta-cell line, INS-1

    Frödin, M; Sekine, N; Roche, E

    1995-01-01

    The signaling pathways whereby glucose and hormonal secretagogues regulate insulin-secretory function, gene transcription, and proliferation of pancreatic beta-cells are not well defined. We show that in the glucose-responsive beta-cell line INS-1, major secretagogue-stimulated signaling pathways...... converge to activate 44-kDa mitogen-activated protein (MAP) kinase. Thus, glucose-induced insulin secretion was found to be associated with a small stimulatory effect on 44-kDa MAP kinase, which was synergistically enhanced by increased levels of intracellular cAMP and by the hormonal secretagogues......-1. Phorbol ester, an activator of protein kinase C, stimulated 44-kDa MAP kinase by both Ca(2+)-dependent and -independent pathways. Nerve growth factor, independently of changes in cytosolic Ca2+, efficiently stimulated 44-kDa MAP kinase without causing insulin release, indicating that activation...

  3. Expression of human choline kinase in NIH 3T3 fibroblasts increases the mitogenic potential of insulin and insulin-like growth factor I.

    Chung, T; Huang, J S; Mukherjee, J J; Crilly, K S; Kiss, Z

    2000-05-01

    In mammalian cells, growth factors, oncogenes, and carcinogens stimulate phosphocholine (PCho) synthesis by choline kinase (CK), suggesting that PCho may regulate cell growth. To validate the role of PCho in mitogenesis, we determined the effects of insulin, insulin-like growth factor I (IGF-I), and other growth factors on DNA synthesis in NIH 3T3 fibroblast sublines highly expressing human choline kinase (CK) without increasing phosphatidylcholine synthesis. In serum-starved CK expressor cells, insulin and IGF-I stimulated DNA synthesis, p70 S6 kinase (p70 S6K) activity, phosphatidylinositol 3-kinase (PI3K) activity, and activating phosphorylation of p42/p44 mitogen-activated protein kinases (MAPK) to greater extents than in the corresponding vector control cells. Furthermore, the CK inhibitor hemicholinium-3 (HC-3) inhibited insulin- and IGF-I-induced DNA synthesis in the CK overexpressors, but not in the vector control cells. The results indicate that high cellular levels of PCho potentiate insulin- and IGF-I-induced DNA synthesis by MAPK- and p70 S6K-regulated mechanisms.

  4. The F-box protein Fbp1 functions in the invasive growth and cell wall integrity mitogen-activated protein kinase (MAPK) pathways in Fusarium oxysporum.

    Miguel-Rojas, Cristina; Hera, Concepcion

    2016-01-01

    F-box proteins determine substrate specificity of the ubiquitin-proteasome system. Previous work has demonstrated that the F-box protein Fbp1, a component of the SCF(Fbp1) E3 ligase complex, is essential for invasive growth and virulence of the fungal plant pathogen Fusarium oxysporum. Here, we show that, in addition to invasive growth, Fbp1 also contributes to vegetative hyphal fusion and fungal adhesion to tomato roots. All of these functions have been shown previously to require the mitogen-activated protein kinase (MAPK) Fmk1. We found that Fbp1 is required for full phosphorylation of Fmk1, indicating that Fbp1 regulates virulence and invasive growth via the Fmk1 pathway. Moreover, the Δfbp1 mutant is hypersensitive to sodium dodecylsulfate (SDS) and calcofluor white (CFW) and shows reduced phosphorylation levels of the cell wall integrity MAPK Mpk1 after SDS treatment. Collectively, these results suggest that Fbp1 contributes to both the invasive growth and cell wall integrity MAPK pathways of F. oxysporum. © 2015 BSPP AND JOHN WILEY & SONS LTD.

  5. Elevated transforming growth factor β and mitogen-activated protein kinase pathways mediate fibrotic traits of Dupuytren's disease fibroblasts

    Krause, Carola; Kloen, Peter; ten Dijke, Peter

    2011-01-01

    ABSTRACT: Dupuytren's disease is a fibroproliferative disorder of the palmar fascia. The treatment used to date has mostly been surgery, but there is a high recurrence rate. Transforming growth factor β (TGF-β) has been implicated as a key stimulator of myofibroblast activity and fascial contraction

  6. Sequence-specific 1H NMR assignments, secondary structure, and location of the calcium binding site in the first epidermal growth factor like domain of blood coagulation factor IX

    Huang, L.H.; Cheng, H.; Sweeney, W.V.; Pardi, A.; Tam, J.P.

    1991-01-01

    Factor IX is a blood clotting protein that contains three regions, including a γ-carboxyglutamic acid (Gla) domain, two tandemly connected epidermal growth factor like (EGF-like) domains, and a serine protease region. The protein exhibits a high-affinity calcium binding site in the first EGF0like domain, in addition to calcium binding in the Gla domain. The first EGF-like domain, factor IX (45-87), has been synthesized. Sequence-specific resonance assignment of the peptide has been made by using 2D NMR techniques, and its secondary structure has been determined. The protein is found to have two antiparallel β-sheets, and preliminary distance geometry calculations indicate that the protein has two domains, separated by Trp 28 , with the overall structure being similar to that of EGF. An NMR investigation of the calcium-bound first EGF-like domain indicates the presence and location of a calcium binding site involving residues on both strands of one of the β-sheets as well as the N-terminal region of the peptide. These results suggest that calcium binding in the first EGF-like domain could induce long-range (possibly interdomain) conformational changes in factor IX, rather than causing structural alterations in the EGF-like domain itself

  7. Inhibition of mitogen-activated protein kinase kinase, DNA methyltransferase, and transforming growth factor-β promotes differentiation of human induced pluripotent stem cells into enterocytes.

    Kodama, Nao; Iwao, Takahiro; Kabeya, Tomoki; Horikawa, Takashi; Niwa, Takuro; Kondo, Yuki; Nakamura, Katsunori; Matsunaga, Tamihide

    2016-06-01

    We previously reported that small-molecule compounds were effective in generating pharmacokinetically functional enterocytes from human induced pluripotent stem (iPS) cells. In this study, to determine whether the compounds promote the differentiation of human iPS cells into enterocytes, we investigated the effects of a combination of mitogen-activated protein kinase kinase (MEK), DNA methyltransferase (DNMT), and transforming growth factor (TGF)-β inhibitors on intestinal differentiation. Human iPS cells cultured on feeder cells were differentiated into endodermal cells by activin A. These endodermal-like cells were then differentiated into intestinal stem cells by fibroblast growth factor 2. Finally, the cells were differentiated into enterocyte cells by epidermal growth factor and small-molecule compounds. After differentiation, mRNA expression levels and drug-metabolizing enzyme activities were measured. The mRNA expression levels of the enterocyte marker sucrase-isomaltase and the major drug-metabolizing enzyme cytochrome P450 (CYP) 3A4 were increased by a combination of MEK, DNMT, and TGF-β inhibitors. The mRNA expression of CYP3A4 was markedly induced by 1α,25-dihydroxyvitamin D3. Metabolic activities of CYP1A1/2, CYP2B6, CYP2C9, CYP2C19, CYP3A4/5, UDP-glucuronosyltransferase, and sulfotransferase were also observed in the differentiated cells. In conclusion, MEK, DNMT, and TGF-β inhibitors can be used to promote the differentiation of human iPS cells into pharmacokinetically functional enterocytes. Copyright © 2016 The Japanese Society for the Study of Xenobiotics. Published by Elsevier Ltd. All rights reserved.

  8. The Air Liquid-interface, a Skin Microenvironment, Promotes Growth of Melanoma Cells, but not Their Apoptosis and Invasion, through Activation of Mitogen-activated Protein Kinase

    Hong Yee, Chong; Aoki, Shigehisa; Uchihashi, Kazuyoshi; Matsunobu, Aki; Yamasaki, Fumio; Misago, Noriyuki; Piao, Meihua; Tetsuji, Uemura; Yonemitsu, Nobuhisa; Sugihara, Hajime; Toda, Shuji

    2010-01-01

    The air-liquid interface (ALI) is a common microenvironment of the skin, but it is unknown whether the ALI affects melanoma cell behaviors. Using a collagen gel invasion assay, immunohistochemistry, and Western blots, here we show that melanoma cell proliferation in cultures with an ALI is higher than melanoma cell proliferation in submerged cultures. Bromodeoxyuridine (BrdU) uptake, an indicator of cell proliferation, of melanoma cells at the ALI was about 3 times that of submerged cells, while ALI and submerged melanoma cells had similar levels of single-stranded DNA (a marker of apoptosis). The ALI enhanced the expression of Raf-1, MEK-1 and pERK-1/2 components of the mitogen-activated protein kinase (MAPK) cascade, in cells more than the submerged condition did. The increases in BrdU uptake and pERK-1/2 expression promoted by ALI was abolished by the MEK inhibitor, PD-98059. ALI-treated and submerged melanoma cells did not infiltrate into the collagen gel, and they showed no significant difference in the expression of the invasion- and motility-related molecules, matrix metalloproteinase-1 and -9, laminin 5, and filamin A. Our data indicate that the ALI, a skin microenvironment, accelerates the growth, but not the apoptosis or invasion, of melanoma cells through MAPK activation

  9. Silibinin and its 2,3-dehydro-derivative inhibit basal cell carcinoma growth via suppression of mitogenic signaling and transcription factors activation.

    Tilley, Cynthia; Deep, Gagan; Agarwal, Chapla; Wempe, Michael F; Biedermann, David; Valentová, Kateřina; Kren, Vladimir; Agarwal, Rajesh

    2016-01-01

    Basal cell carcinoma (BCC) is the most common cancer worldwide, and its current treatment options are insufficient and toxic. Surprisingly, unlike several other malignancies, chemopreventive efforts against BCC are almost lacking. Silibinin, a natural agent from milk thistle seeds, has shown strong efficacy against several cancers including ultraviolet radiation-induced skin (squamous) cancer; however, its potential activity against BCC is not yet examined. Herein, for the first time, we report the efficacy of silibinin and its oxidation product 2,3-dehydrosilibinin (DHS) against BCC both in vitro and in vivo using ASZ (p53 mutated) and BSZ (p53 deleted) cell lines derived from murine BCC tumors. Both silibinin and DHS significantly inhibited cell growth and clonogenicity while inducing apoptosis in a dose- and time-dependent manner, with DHS showing higher activity at lower concentrations. Both agents also inhibited the mitogenic signaling by reducing EGFR, ERK1/2, Akt, and STAT3 phosphorylation and suppressed the activation of transcription factors NF-κB and AP-1. More importantly, in an ectopic allograft model, oral administration of silibinin and DHS (200 mg/kg body weight) strongly inhibited the ASZ tumor growth by 44% and 71% (P < 0.05), respectively, and decreased the expression of proliferation biomarkers (PCNA and cyclin D1) as well as NF-κB p50 and c-Fos in the tumor tissues. Taken together, these results provide the first evidence for the efficacy and usefulness of silibinin and its derivative DHS against BCC, and suggest the need for additional studies with these agents in pre-clinical and clinical BCC chemoprevention and therapy models. © 2014 Wiley Periodicals, Inc.

  10. Colletotrichum higginsianum Mitogen-Activated Protein Kinase ChMK1: Role in Growth, Cell Wall Integrity, Colony Melanization and Pathogenicity

    Wei Wei

    2016-08-01

    Full Text Available Colletotrichum higginsianum is an economically important pathogen that causes anthracnose disease in a wide range of cruciferous crops. To facilitate the efficient control of anthracnose disease, it will be important to understand the mechanism by which the cruciferous crops and C. higginsianum interact. A key step in understanding this interaction is characterizing the mitogen-activated protein kinases (MAPK signaling pathway of C. higginsianum. MAPK plays important roles in diverse physiological processes of multiple pathogens. In this study, a Fus3/Kss1-related MAPK gene, ChMK1, from C. higginsianum was analyzed. The results showed that the Fus3/Kss1-related MAPK ChMK1 plays a significant role in cell wall integrity. Targeted deletion of ChMK1 resulted in a hypersensitivity to cell wall inhibitors, reduced conidiation and albinistic colonies. Further, the deletion mutant was also unable to form melanized appressorium, a specialized infection structure that is necessary for successful infection. Therefore, the deletion mutant loses pathogenicity on A. thaliana leaves, demonstrating that ChMK1 plays an essential role in the early infection step. In addition, the ChMK1 deletion mutant showed an attenuated growth rate that is different from that of its homologue in C. lagenarium, indicating the diverse roles that Fus3/Kss1-related MAPKs plays in phytopathogenic fungi. Furthermore, the expression level of three melanin synthesis associated genes were clearly decreased in the albinistic ChMK1 mutant compared to that of the wild type strain, suggesting that ChMK1 is also required for colony melanization in C. higginsianum.

  11. Enhancing effects of thymopoietin and T cell growth factor on mitogenic responsiveness and colony formation of lymphocytes from patients with preleukemia

    Knox, S.J.; Greenberg, B.R.; Anderson, R.W.; Shifrine, M.

    1983-01-01

    Cloning efficiencies and mitogenic responsiveness of lymphocytes from patients with preleukemic disorders are significantly depressed compared to normal values. TP-5 and IL-2 markedly increased the cloning efficiency and mitogenic responsiveness of lymphocytes from many of the preleukemic patients studied, while there was little or no effect in control cultures. Enhancement of lymphocyte responsiveness with TP-5 and IL-2 suggests the presence of maturational/-functional defects in these patients which may be compensated for in part by addition of TP-5 and IL-2

  12. Intra-tumoural vessel area estimated by expression of epidermal growth factor-like domain 7 and microRNA-126 in primary tumours and metastases of patients with colorectal cancer

    Hansen, T. F.; Nielsen, Boye Schnack; Jakobsen, Anders

    2015-01-01

    factor-like domain 7 (EGFL7) and microRNA-126 (miRNA-126) in primary tumours from patients with stage II-IV colorectal cancer (CRC) and in paired samples of primary tumours, regional lymph node metastases and distant metastases. Methods: A total of 126 patients were included. Analyses were performed...

  13. Intra-tumoural vessel area estimated by expression of epidermal growth factor-like domain 7 and microRNA-126 in primary tumours and metastases of patients with colorectal cancer

    Hansen, T. F.; Nielsen, Boye Schnack; Jakobsen, Anders

    2015-01-01

    Background: Understanding the biological properties of potential drug targets are important. This is especially true for anti-angiogenic therapies in the search for potential biomarkers. The aim of the present descriptive study was to analyse the intra-tumoural expressions of epidermal growth...

  14. Levels of the epidermal growth factor-like peptide amphiregulin in follicular fluid reflect the mode of triggering ovulation: a comparison between gonadotrophin-releasing hormone agonist and urinary human chorionic gonadotrophin

    Al Humaidan, Peter Samir Heskjær; Westergaard, Lars Grabow; Mikkelsen, Anne Lis

    2011-01-01

    . INTERVENTION(S): Ovulation triggered with either urinary hCG or GnRH agonist (GnRH-a). Controls: 15 FF samples from small antral follicles (3-9 mm) and 12 FF samples from natural cycle. MAIN OUTCOME MEASURE(S): Follicular fluid concentration of AR, P(4), E(2), vascular endothelial growth factor, and inhibin B...... antral follicles only 5 out of 15 follicles contained measurable amounts of AR. When urinary hCG and GnRH-a triggering were compared, FF P(4) was significantly higher after urinary hCG triggering, whereas no difference was seen regarding E(2), vascular endothelial growth factor, and inhibin B. A total...... of 14% more metaphase II oocytes and 11% more transferable embryos were obtained after GnRH-a triggering. CONCLUSION(S): This study suggests that oocyte competence is linked to granulosa cell AR secretion....

  15. Amitriptyline induces early growth response-1 gene expression via ERK and JNK mitogen-activated protein kinase pathways in rat C6 glial cells.

    Chung, Eun Young; Shin, Soon Young; Lee, Young Han

    2007-07-05

    Astrocytes play important roles in guiding the construction of the nervous system, controlling extracellular ions and neurotransmitters, and regulating CNS synaptogenesis. Egr-1 is a transcription factor involved in neuronal differentiation and astrocyte cell proliferation. In this study, we investigated whether the tricyclic antidepressant (TCA) amitriptyline induces Egr-1 expression in astrocytes using rat C6 glioma cells as a model. We found that amitriptyline increased the expression of Egr-1 in a dose- and time-dependent manner. The amitriptyline-induced Egr-1 expression was mediated through serum response elements (SREs) in the Egr-1 promoter. SREs were activated by the Ets-domain transcription factor Elk-1 through the ERK and JNK mitogen-activated protein (MAP) kinase pathways. The inhibition of the ERK and JNK MAP kinase signals attenuated amitriptyline-induced transactivation of Gal4-Elk-1 and Egr-1 promoter activity. Our findings suggest that the induction of Egr-1 expression in astrocytes may be required to attain the therapeutic effects of antidepressant drugs.

  16. Silencing of the Mitogen-Activated Protein Kinases (MAPK) Fus3 and Slt2 in Pseudocercospora fijiensis Reduces Growth and Virulence on Host Plants.

    Onyilo, Francis; Tusiime, Geoffrey; Tripathi, Jaindra N; Chen, Li-Hung; Falk, Bryce; Stergiopoulos, Ioannis; Tushemereirwe, Wilberforce; Kubiriba, Jerome; Tripathi, Leena

    2018-01-01

    Pseudocercospora fijiensis , causal agent of the black Sigatoka disease (BSD) of Musa spp., has spread globally since its discovery in Fiji 1963 to all the banana and plantain growing areas across the globe. It is becoming the most damaging and economically important disease of this crop. The identification and characterization of genes that regulate infection processes and pathogenicity in P. fijiensis will provide important knowledge for the development of disease-resistant cultivars. In many fungal plant pathogens, the Fus3 and Slt2 are reported to be essential for pathogenicity. Fus3 regulates filamentous-invasion pathways including the formation of infection structures, sporulation, virulence, and invasive and filamentous growth, whereas Slt2 is involved in the cell-wall integrity pathway, virulence, invasive growth, and colonization in host tissues. Here, we used RNAi-mediated gene silencing to investigate the role of the Slt2 and Fus3 homologs in P. fijiensis in pathogen invasiveness, growth and pathogenicity. The PfSlt2 and PfFus3 silenced P. fijiensis transformants showed significantly lower gene expression and reduced virulence, invasive growth, and lower biomass in infected leaf tissues of East African Highland Banana (EAHB). This study suggests that Slt2 and Fus3 MAPK signaling pathways play important roles in plant infection and pathogenic growth of fungal pathogens. The silencing of these vital fungal genes through host-induced gene silencing (HIG) could be an alternative strategy for developing transgenic banana and plantain resistant to BSD.

  17. Silencing of the Mitogen-Activated Protein Kinases (MAPK Fus3 and Slt2 in Pseudocercospora fijiensis Reduces Growth and Virulence on Host Plants

    Francis Onyilo

    2018-03-01

    Full Text Available Pseudocercospora fijiensis, causal agent of the black Sigatoka disease (BSD of Musa spp., has spread globally since its discovery in Fiji 1963 to all the banana and plantain growing areas across the globe. It is becoming the most damaging and economically important disease of this crop. The identification and characterization of genes that regulate infection processes and pathogenicity in P. fijiensis will provide important knowledge for the development of disease-resistant cultivars. In many fungal plant pathogens, the Fus3 and Slt2 are reported to be essential for pathogenicity. Fus3 regulates filamentous-invasion pathways including the formation of infection structures, sporulation, virulence, and invasive and filamentous growth, whereas Slt2 is involved in the cell-wall integrity pathway, virulence, invasive growth, and colonization in host tissues. Here, we used RNAi-mediated gene silencing to investigate the role of the Slt2 and Fus3 homologs in P. fijiensis in pathogen invasiveness, growth and pathogenicity. The PfSlt2 and PfFus3 silenced P. fijiensis transformants showed significantly lower gene expression and reduced virulence, invasive growth, and lower biomass in infected leaf tissues of East African Highland Banana (EAHB. This study suggests that Slt2 and Fus3 MAPK signaling pathways play important roles in plant infection and pathogenic growth of fungal pathogens. The silencing of these vital fungal genes through host-induced gene silencing (HIG could be an alternative strategy for developing transgenic banana and plantain resistant to BSD.

  18. A single amino acid substitution is sufficient to modify the mitogenic properties of the epidermal growth factor receptor to resemble that of gp185erbB-2

    Di Fiore, P P; Helin, K; Kraus, M H

    1992-01-01

    The epidermal growth factor (EGF) receptor (EGFR) and the erbB-2 gene product, gp185erbB-2, exhibit distinct abilities to stimulate mitogenesis in different target cells. By using chimeric molecules between these two receptors, we have previously shown that their intracellular juxtamembrane regio...

  19. Whey protein concentrate enhances intestinal integrity and influences transforming growth factor-β1 and mitogen-activated protein kinase signalling pathways in piglets after lipopolysaccharide challenge.

    Xiao, Kan; Jiao, Lefei; Cao, Shuting; Song, Zehe; Hu, Caihong; Han, Xinyan

    2016-03-28

    Whey protein concentrate (WPC) has been reported to have protective effects on the intestinal barrier. However, the molecular mechanisms involved are not fully elucidated. Transforming growth factor-β1 (TGF-β1) is an important component in the WPC, but whether TGF-β1 plays a role in these processes is not clear. The aim of this study was to investigate the protective effects of WPC on the intestinal epithelial barrier as well as whether TGF-β1 is involved in these protection processes in a piglet model after lipopolysaccharide (LPS) challenge. In total, eighteen weanling pigs were randomly allocated to one of the following three treatment groups: (1) non-challenged control and control diet; (2) LPS-challenged control and control diet; (3) LPS+5 %WPC diet. After 19 d of feeding with control or 5 %WPC diets, pigs were injected with LPS or saline. At 4 h after injection, pigs were killed to harvest jejunal samples. The results showed that WPC improved (Pprotein, phosphorylated-Smad2 expression and Smad4 and Smad7 mRNA expressions and decreased (Pprotein kinase signalling pathways.

  20. Activin and TGFβ use diverging mitogenic signaling in advanced colon cancer

    Bauer, Jessica; Ozden, Ozkan; Akagi, Naomi; Carroll, Timothy; Principe, Daniel R.; Staudacher, Jonas J.; Spehlmann, Martina E.; Eckmann, Lars; Grippo, Paul J.; Jung, Barbara

    2015-01-01

    Background Understanding cell signaling pathways that contribute to metastatic colon cancer is critical to risk stratification in the era of personalized therapeutics. Here, we dissect the unique involvement of mitogenic pathways in a TGFβ or activin-induced metastatic phenotype of colon cancer. Method Mitogenic signaling/growth factor receptor status and p21 localization were correlated in primary colon cancers and intestinal tumors from either AOM/DSS treated ACVR2A (activin receptor 2) −/−...

  1. Dealing With A Controllable Risk Factor Like Diet In The ...

    Cardiovascular disease (CVD) is a silent killer in Nigeria and many parts of the world. Certain factors increase the risk of CVD. While there are controllable factors that contribute and predispose to the development of CVD like diet, exercise, tobacco use, high blood pressure and obesity, there are uncontrollable factors like ...

  2. Nicotine as a mitogenic stimulus for pancreatic acinar cell proliferation

    Parimal Chowdhury; Kodetthoor B Udupa

    2006-01-01

    Cell proliferation is an important process in life for growth of normal and cancer cells. The signal transduction pathways activated during this process are strictly regulated. This editorial focuses on the role of nicotine,a mitogen, in the induction of signaling pathways resulting in proliferation of pancreatic tumor cells and compares these events with those in normal acinar cells isolated from the rat pancreas. The data shows striking similarities between these two cellular systems.In addition, the editorial reviews very recent literature of the contribution of MAPK signaling in cell lines associated with human diseases. A prospective cellular model of nicotine induced activation of MAPK cascade is presented.

  3. Human prostatic cancer cells, PC3, elaborate mitogenic activity which selectively stimulates human bone cells

    Perkel, V.S.; Mohan, S.; Herring, S.J.; Baylink, D.J.; Linkhart, T.A.

    1990-01-01

    Prostatic cancer typically produces osteoblastic metastases which are not attended by marrow fibrosis. In the present study we sought to test the hypothesis that prostatic cancer cells produce factor(s) which act selectively on human osteoblasts. Such a paracrine mechanism would explain the observed increase in osteoblasts, unaccompanied by an increase in marrow fibroblasts. To test this hypothesis we investigated the mitogenic activity released by the human prostatic tumor cell line, PC3. PC3 cells have been reported previously to produce mitogenic activity for cells that was relatively specific for rat osteoblasts compared to rat fibroblasts. However, the effects of this activity on human cells has not been examined previously. PC3-conditioned medium (CM) (5-50 micrograms CM protein/ml) stimulated human osteoblast proliferation by 200-950% yet did not stimulate human fibroblast proliferation ([3H]thymidine incorporation). PC3 CM also increased cell numbers in human osteoblast but not fibroblast cell cultures. To determine whether the osteoblast-specific mitogenic activity could be attributed to known bone growth factors, specific assays for these growth factors were performed. PC3 CM contained 10 pg insulin-like growth factor (IGF) I, less than 2 pg IGF II, 54 pg basic fibroblast growth factor, and 16 pg transforming growth factor beta/microgram CM protein. None of these growth factors alone or in combination could account for the observed osteoblast-specific PC3 cell-derived mitogenic activity. Furthermore, when 5 micrograms/ml PC3 CM was tested in combination with maximally effective concentrations of either basic fibroblast growth factor, IGF I, IGF II, or transforming growth factor beta, it produced an additive effect suggesting that PC3 CM stimulates osteoblast proliferation by a mechanism independent of these bone mitogens

  4. Mitogen-activated protein kinases mediate Mycobacterium ...

    2012-01-19

    Jan 19, 2012 ... CD44, an adhesion molecule, has been reported to be a binding site for ... receptors in mediating mitogen-activated protein kinase activation. ... surface expression and tumour necrosis factor-alpha levels, ... Abbreviations used: Abs, antibodies; ANOVA, analysis of variance; AP-1, activator protein -1; BCG, ...

  5. Effects of polycationic compounds on mitogen stimulation

    Heron, I; Larsen, B; Hokland, M

    1981-01-01

    The effects of polycations added to phytomitogen stimulated human lymphocyte cultures have been studied. Within certain dose ranges all polycations tested gave rise to augmented thymidine uptake in mitogen stimulated cultures. The optimum enhancing concentrations of polycations was depending on t...

  6. Liquid scintillation vial for radiometric assay of lymphocyte carbohydrate metabolism in response to mitogens

    Tran, N.; Wagner, H.N. Jr.

    1978-01-01

    We have demonstrated that mitogens--i.e., PHA and Con.A--stimulate lymphocyte carbohydrate metabolism using a liquid-scintillation vial with conventional liquid-scintillation detectors. The results showed that this enclosed system can be useful for development of rapid in vitro tests of lymphocytes immune responsiveness, as well as for radiometric detection of bacterial growth in various gaseous atmospheres

  7. Lack of direct mitogenic activity of dichloroacetate and trichloroacetate in cultured rat hepatocytes

    Walgren, Jennie L.; Kurtz, David T.; McMillan, JoEllyn M.

    2005-01-01

    Dichloroacetate (DCA) and trichloroacetate (TCA) are hepatocarcinogenic metabolites of the common groundwater contaminant, 1,1,2-trichloroethylene. DCA and TCA have been shown to induce hepatocyte proliferation in vivo, but it is not known if this response is the result of direct mitogenic activity or whether cell replication occurs indirectly in response to tissue injury or inflammation. In this study we used primary cultures of rat hepatocytes, a species susceptible to DCA- but not TCA-induced hepatocarcinogenesis, to determine whether DCA and TCA are direct hepatocyte mitogens. Rat hepatocytes, cultured in growth factor-free medium, were treated with 0.01-1.0 mM DCA or TCA for 10-40 h; cell replication was then assessed by measuring incorporation of 3 H-thymidine into DNA and by cell counts. DCA or TCA treatment did not alter 3 H-thymidine incorporation in the cultured hepatocytes. Although an increase in cell number was not observed, DCA treatment significantly abrogated the normal background cell loss, suggesting an ability to inhibit apoptotic cell death in primary hepatocyte cultures. Furthermore, treatment with DCA synergistically enhanced the mitogenic response to epidermal growth factor. The data indicate that DCA and TCA are not direct mitogens in hepatocyte cultures, which is of interest in view of their ability to stimulate hepatocyte replication in vivo. Nevertheless, the synergistic enhancement of epidermal growth factor-induced hepatocyte replication by DCA is of particular interest and warrants further study

  8. The transcriptional co-factor RIP140 regulates mammary gland development by promoting the generation of key mitogenic signals.

    Nautiyal, Jaya; Steel, Jennifer H; Mane, Meritxell Rosell; Oduwole, Olayiwola; Poliandri, Ariel; Alexi, Xanthippi; Wood, Nicholas; Poutanen, Matti; Zwart, Wilbert; Stingl, John; Parker, Malcolm G

    2013-03-01

    Nuclear receptor interacting protein (Nrip1), also known as RIP140, is a co-regulator for nuclear receptors that plays an essential role in ovulation by regulating the expression of the epidermal growth factor-like family of growth factors. Although several studies indicate a role for RIP140 in breast cancer, its role in the development of the mammary gland is unclear. By using RIP140-null and RIP140 transgenic mice, we demonstrate that RIP140 is an essential factor for normal mammary gland development and that it functions by mediating oestrogen signalling. RIP140-null mice exhibit minimal ductal elongation with no side-branching, whereas RIP140-overexpressing mice show increased cell proliferation and ductal branching with age. Tissue recombination experiments demonstrate that RIP140 expression is required in both the mammary epithelial and stromal compartments for ductal elongation during puberty and that loss of RIP140 leads to a catastrophic loss of the mammary epithelium, whereas RIP140 overexpression augments the mammary basal cell population and shifts the progenitor/differentiated cell balance within the luminal cell compartment towards the progenitors. For the first time, we present a genome-wide global view of oestrogen receptor-α (ERα) binding events in the developing mammary gland, which unravels 881 ERα binding sites. Unbiased evaluation of several ERα binding sites for RIP140 co-occupancy reveals selectivity and demonstrates that RIP140 acts as a co-regulator with ERα to regulate directly the expression of amphiregulin (Areg), the progesterone receptor (Pgr) and signal transducer and activator of transcription 5a (Stat5a), factors that influence key mitogenic pathways that regulate normal mammary gland development.

  9. Factors likely to enhance mycotoxin introduction into the human diet ...

    In Kenya, several incidences of acute food poisoning due to mycotoxins ... Chronic exposure to mycotoxins has been linked to liver cancer, hepatitis infections, impaired immunity and stunted growth in children. ... These include eating habits, existing marketing problems which encourage ... AJOL African Journals Online.

  10. Parathyroid mitogenic activity in plasma from patients with familial multiple endocrine neoplasia type 1

    Brandi, M.L.; Aurbach, G.D.; Fitzpatrick, L.A.; Quarto, R.; Spiegel, A.M.; Bliziotes, M.M.; Norton, J.A.; Doppman, J.L.; Marx, S.J.

    1986-01-01

    Hyperplasia of the parathyroid glands is a central feature of familial multiple endocrine neoplasia type 1. We used cultured bovine parathyroid cells to test for mitogenic activity in plasma from patients with this disorder. Normal plasma stimulated [ 3 H]thymidine incorporation, on the average, to the same extent as it was stimulated in a plasma-free control culture. This contrasted with the results of the tests with plasma from patients with familial multiple endocrine neoplasia type 1, in which parathyroid mitogenic activity increased 2400 percent over the control value (P less than 0.001). Plasma from these patients also stimulated the proliferation of bovine parathyroid cells in culture, whereas plasma from normal subjects inhibited it. Parathyroid mitogenic activity in plasma from the patients with familial multiple endocrine neoplasia type 1 was greater than that in plasma from patients with various other disorders, including sporadic primary hyperparathyroidism (with adenoma, hyperplasia, or cancer of the parathyroid), sporadic primary hypergastrinemia, sporadic pituitary tumor, familial hypocalciuric hypercalcemia, and multiple endocrine neoplasia type 2 (P less than 0.05). Parathyroid mitogenic activity in the plasma of patients with familial multiple endocrine neoplasia type 1 persisted for up to four years after total parathyroidectomy. The plasma also had far more mitogenic activity in cultures of parathyroid cells than did optimal concentrations of known growth factors or of any parathyroid secretagogue. This mitogenic activity had an apparent molecular weight of 50,000 to 55,000. We conclude that primary hyperparathyroidism in familial multiple endocrine neoplasia type 1 may have a humoral cause

  11. Mitogenic stimuli and phosphatidylinositol (PI) turnover in cultured 3T3 fibroblasts

    Kohler, C.; Petersen, R.

    1986-01-01

    The hydrolysis of PI and polyphosphoinositides by phopholipase C is an early and rapid response to cell activation by a variety of neurotransmitters, hormones, growth factors and pharmacological agonists. The authors have examined the role of PI turnover and the generation of second messengers (diacylglycerol and inositol trisphosphate) in the mitogenic response of cultured Balb/c and Swiss 3T3 cells to polypeptide growth factors. Cells were prelabelled with 3 H inositol for 18-20 hours, washed and suspended in Herpes + Li + buffer, and stimulated with platelet-derived growth factor (PDGF), vasopressin, insulin, and other growth factors. PI turnover was measured as the increase in total inositol phosphate (IP) production. IP1, IP2, and IP3 were characterized by sequential elution from a Dowex column. Partially purified PDGF produced a 2-4 fold stimulation of total IP production. This was seen as early as 30 seconds after stimulation and increased for up to 1-2 hours. Balb/c cells were more sensitive than Swiss cells to the mitogenic and PI effects of PDGF. Other mitogenic stimuli had differential effects on PI turnover. Vasopressin (4-400 ng/ml) markedly stimulated PI turnover (3-6 fold) in Swiss, but not Balb/c cells. Insulin (100 ng/ml - 10 μg/ml) increased total IP to a greater degree in Balb/c cells. Epidermal growth factor (10 ng/ml - 10 μg/ml) had no effect on PI turnover and fibroblast growth factor (10 ng/ml - 10 μg/ml) only stimulated at the higher concentrations in Swiss cells. Thrombin (1U/ml - 10 U/ml) produced a 1.5 - 2 fold stimulation in Balb/c cells. Thus, various polypeptide growth factors have differential effects on PI turnover depending on their mitogenic potential and the effector cell type

  12. Essential Roles of Raf/Extracellular Signal-regulated Kinase/Mitogen-activated Protein Kinase Pathway, YY1, and Ca2+ Influx in Growth Arrest of Human Vascular Smooth Muscle Cells by Bilirubin*

    Stoeckius, Marlon; Erat, Anna; Fujikawa, Tatsuya; Hiromura, Makoto; Koulova, Anna; Otterbein, Leo; Bianchi, Cesario; Tobiasch, Edda; Dagon, Yossi; Sellke, Frank W.; Usheva, Anny

    2012-01-01

    The biological effects of bilirubin, still poorly understood, are concentration-dependent ranging from cell protection to toxicity. Here we present data that at high nontoxic physiological concentrations, bilirubin inhibits growth of proliferating human coronary artery smooth muscle cells by three events. It impairs the activation of Raf/ERK/MAPK pathway and the cellular Raf and cyclin D1 content that results in retinoblastoma protein hypophosphorylation on amino acids S608 and S780. These events impede the release of YY1 to the nuclei and its availability to regulate the expression of genes and to support cellular proliferation. Moreover, altered calcium influx and calpain II protease activation leads to proteolytical degradation of transcription factor YY1. We conclude that in the serum-stimulated human vascular smooth muscle primary cell cultures, bilirubin favors growth arrest, and we propose that this activity is regulated by its interaction with the Raf/ERK/MAPK pathway, effect on cyclin D1 and Raf content, altered retinoblastoma protein profile of hypophosphorylation, calcium influx, and YY1 proteolysis. We propose that these activities together culminate in diminished 5 S and 45 S ribosomal RNA synthesis and cell growth arrest. The observations provide important mechanistic insight into the molecular mechanisms underlying the transition of human vascular smooth muscle cells from proliferative to contractile phenotype and the role of bilirubin in this transition. PMID:22262839

  13. Insulin-like growth factor (IGF)-I obliterates the pregnancy-associated protection against mammary carcinogenesis in rats: evidence that IGF-I enhances cancer progression through estrogen receptor-α activation via the mitogen-activated protein kinase pathway

    Thordarson, Gudmundur; Slusher, Nicole; Leong, Harriet; Ochoa, Dafne; Rajkumar, Lakshmanaswamy; Guzman, Raphael; Nandi, Satyabrata; Talamantes, Frank

    2004-01-01

    rats. We argue that tumor initiation (transformation and fixation of mutations) may be similar in parous and age-matched virgin animals, suggesting that the main differences in tumor formation lie in differences in tumor progression caused by the altered hormonal environment associated with parity. Furthermore, we provide evidence supporting the notion that tumor growth promotion seen in IGF-I-treated parous rats is caused by activation of estrogen receptor-α via the Raf/Ras/mitogen-activated protein kinase cascade

  14. Monoclonal antibody to the type I insulin-like growth factor (IGF-I) receptor blocks IGF-I receptor-mediated DNA synthesis: clarification of the mitogenic mechanisms of IGF-I and insulin in human skin fibroblasts

    Flier, J.S.; Usher, P.; Moses, A.C.

    1986-01-01

    Insulin and insulin-like growth factor type I (IGF-I) stimulate an overlapping spectrum of biological responses in human skin fibroblasts. Although insulin and IGF-I are known to stimulate the incorporation of [ 3 H]thymidine into DNA in these cells, the identify of the receptor(s) that mediates this effect has not been fully clarified. The mouse anti-human IGF-I receptor antibody αIR-3 binds with specificity to IGF-I but not to insulin receptors in human placental membranes; it also specifically inhibits the binding of 125 I-labeled IGF-I but not 125 I-labeled insulin to suspensions of human skin fibroblasts in a dose-dependent manner. αIR-3 competitively inhibits IGF-I-mediated stimulation of [ 3 H]thymidine incorporation into DNA. This inhibition is dependent on the concentration of αIR-3 and in the presence of a fixed antibody concentration can be partially overcome by high concentrations of IGF-I. In contrast, at concentrations of 3 H]thymidine incorporation is not inhibited by αIR-3. However, the incremental effects of higher concentrations (> 1 μg/ml) of insulin on [ 3 H]thymidine incorporation are inhibited by αIR-3. αIR-3 is a highly specific antagonist of IGF-I receptor-mediated mitogenesis in human skin fibroblasts. By using this antibody, it is shown directly that insulin can act through the IGF-I receptor to stimulate DNA synthesis but can also activate this effect through the insulin receptor itself

  15. Transcriptional integration of mitogenic and mechanical signals by Myc and YAP.

    Croci, Ottavio; De Fazio, Serena; Biagioni, Francesca; Donato, Elisa; Caganova, Marieta; Curti, Laura; Doni, Mirko; Sberna, Silvia; Aldeghi, Deborah; Biancotto, Chiara; Verrecchia, Alessandro; Olivero, Daniela; Amati, Bruno; Campaner, Stefano

    2017-10-15

    Mammalian cells must integrate environmental cues to determine coherent physiological responses. The transcription factors Myc and YAP-TEAD act downstream from mitogenic signals, with the latter responding also to mechanical cues. Here, we show that these factors coordinately regulate genes required for cell proliferation. Activation of Myc led to extensive association with its genomic targets, most of which were prebound by TEAD. At these loci, recruitment of YAP was Myc-dependent and led to full transcriptional activation. This cooperation was critical for cell cycle entry, organ growth, and tumorigenesis. Thus, Myc and YAP-TEAD integrate mitogenic and mechanical cues at the transcriptional level to provide multifactorial control of cell proliferation. © 2017 Croci et al.; Published by Cold Spring Harbor Laboratory Press.

  16. Enhanced tumor imaging with pokeweed mitogen

    Bitner, D.M.; Mann, P.L.; D'Souza, P.; Wenk, R.; Baughman, D.G.; Quesada, S.M.; Purvis, R.; Born, J.L.; Matwiyoff, N.A.; Eshima, D.

    1993-01-01

    Traditional tumor imaging with biotracer techniques relies solely on the target specificity of the biomolecule. We hypothesize that specific imaging is possible by altering the rate of tissue clearance of any given radiotracer. Pokeweed mitogen (PWM) as a biomodulator, represents a class of molecules which regulate cellular differentiation and cell-cell interactions and, as part of these mechanisms alter tissue clearance rates. Utilizing the B-16/C57BL/6 model, 7 days post-transplantation, 10 animals were imaged following an i.v. injection of 1-2 mCi 99m Tc-PWM in order to visualize the tumors and determine the optimal imaging kinetics. A specific tumor image is achieved between 120 and 240 min post-injection. In addition, tumor imaging studies using a non-tumor-specific biomolecule were conducted by injecting 19 animals i.v. with 1-2 mCi of 99m Tc-human serum albumin (HSA). Twelve of these animals were given 10 μg of PWM i.p. at various intervals prior to the 99m Tc-HAS administration. Imaging and biodistribution studies were performed at various intervals up to 2 h post- 99m Tc-HSA injection. A 32-59% increase in the tumor-to-muscle ratio was observed in the PWM-treated animals relative to the non-treated controls. To further investigate the PWM-induced tissue clearance alteration hypothesis, tissue clearance studies using 99m Tc-diethylenetriaminepentaacetic acid (DTPA) were conducted in non-tumor bearing ICR mice and the B-16/C57BL/6 tumor bearing animals. 99m Tc-DTPA normal tissue clearance rates were significantly increased in the PWM treated animals relative to the non-treated controls. (author)

  17. Mitogenic Properties Of Lectin From Mucuna Sloanei Seed Extracts ...

    (p<0.05) increases in the values of the immunological parameters relative to those seen in the controls. This study, suggest that the isolated lectin from mucona sloanei seeds possesses mitogenic properties, and may be useful in the diagnosis and treatment of certain diseases such as blood typing disorders and obesity.

  18. Cytokine production by porcine mononuclear leukocytes stimulated by mitogens

    Rašková, G.; Kovářů, František; Bártová, J.

    2005-01-01

    Roč. 74, - (2005), s. 521-525 ISSN 0001-7213 R&D Projects: GA ČR GA524/05/0267 Institutional research plan: CEZ:AV0Z50450515 Keywords : cytokine * ELISpot * mitogen Subject RIV: ED - Physiology Impact factor: 0.353, year: 2005

  19. Systems biology analysis of mitogen activated protein kinase inhibitor resistance in malignant melanoma.

    Zecena, Helma; Tveit, Daniel; Wang, Zi; Farhat, Ahmed; Panchal, Parvita; Liu, Jing; Singh, Simar J; Sanghera, Amandeep; Bainiwal, Ajay; Teo, Shuan Y; Meyskens, Frank L; Liu-Smith, Feng; Filipp, Fabian V

    2018-04-04

    Kinase inhibition in the mitogen activated protein kinase (MAPK) pathway is a standard therapy for cancer patients with activating BRAF mutations. However, the anti-tumorigenic effect and clinical benefit are only transient, and tumors are prone to treatment resistance and relapse. To elucidate mechanistic insights into drug resistance, we have established an in vitro cellular model of MAPK inhibitor resistance in malignant melanoma. The cellular model evolved in response to clinical dosage of the BRAF inhibitor, vemurafenib, PLX4032. We conducted transcriptomic expression profiling using RNA-Seq and RT-qPCR arrays. Pathways of melanogenesis, MAPK signaling, cell cycle, and metabolism were significantly enriched among the set of differentially expressed genes of vemurafenib-resistant cells vs control. The underlying mechanism of treatment resistance and pathway rewiring was uncovered to be based on non-genomic adaptation and validated in two distinct melanoma models, SK-MEL-28 and A375. Both cell lines have activating BRAF mutations and display metastatic potential. Downregulation of dual specific phosphatases, tumor suppressors, and negative MAPK regulators reengages mitogenic signaling. Upregulation of growth factors, cytokines, and cognate receptors triggers signaling pathways circumventing BRAF blockage. Further, changes in amino acid and one-carbon metabolism support cellular proliferation despite MAPK inhibitor treatment. In addition, treatment-resistant cells upregulate pigmentation and melanogenesis, pathways which partially overlap with MAPK signaling. Upstream regulator analysis discovered significant perturbation in oncogenic forkhead box and hypoxia inducible factor family transcription factors. The established cellular models offer mechanistic insight into cellular changes and therapeutic targets under inhibitor resistance in malignant melanoma. At a systems biology level, the MAPK pathway undergoes major rewiring while acquiring inhibitor resistance

  20. Mitogen-activated protein kinases in the acute diabetic myocardium

    Strnisková, M.; Barančík, M.; Neckář, Jan; Ravingerová, T.

    2003-01-01

    Roč. 249, 1-2 (2003), s. 59-65 ISSN 0300-8177 R&D Projects: GA MŠk LN00A069 Grant - others:VEGA(SK) 2/2063/22 Institutional research plan: CEZ:AV0Z5011922 Keywords : experimental diabetes * ischemia * mitogen-activated protein kinases (MAPK) Subject RIV: ED - Physiology Impact factor: 1.763, year: 2003

  1. Ligand binding affinity at the insulin receptor isoform A (IR-A and subsequent IR-A tyrosine phosphorylation kinetics are important determinants of mitogenic biological outcomes.

    Harinda eRajapaksha

    2015-07-01

    Full Text Available The insulin receptor (IR is a tyrosine kinase receptor that can mediate both metabolic and mitogenic biological actions. The IR isoform-A (IR-A arises from alternative splicing of exon 11 and has different ligand binding and signalling properties compared to the IR isoform-B. The IR-A not only binds insulin but also insulin-like growth factor-II (IGF-II with high affinity. IGF-II acting through the IR-A promotes cancer cell proliferation, survival and migration by activating some unique signalling molecules compared to those activated by insulin. This observation led us to investigate whether the different IR-A signalling outcomes in response to IGF-II and insulin could be attributed to phosphorylation of a different subset of IR-A tyrosine residues or to the phosphorylation kinetics. We correlated IR-A phosphorylation to activation of molecules involved in mitogenic and metabolic signalling (MAPK and Akt and receptor internalisation rates (related to mitogenic signalling. We also extended this study to incorporate two ligands that are known to promote predominantly mitogenic ([His4, Tyr15, Thr49, Ile51] IGF-I, qIGF-I or metabolic (S597 peptide biological actions, to see if common mechanisms can be used to define mitogenic or metabolic signalling through the IR-A. The 3-fold lower mitogenic action of IGF-II compared to insulin was associated with a decreased potency in activation of Y960, Y1146, Y1150, Y1151, Y1316 and Y1322, in MAPK phosphorylation and in IR-A internalization. With the poorly mitogenic S597 peptide it was a decreased rate of tyrosine phosphorylation rather than potency that was associated with a low mitogenic potential. We conclude that both decreased affinity of IR-A binding and the kinetics of IR-A phosphorylation can independently lead to a lower mitogenic activity. None of the studied parameters could account for the lower metabolic activity of qIGF-I.

  2. Cloning and functional analysis of human mTERFL encoding a novel mitochondrial transcription termination factor-like protein

    Chen Yao; Zhou Guangjin; Yu Min; He Yungang; Tang Wei; Lai Jianhua; He Jie; Liu Wanguo; Tan Deyong

    2005-01-01

    Serum plays an important role in the regulation of cell cycle and cell growth. To identify novel serum-inhibitory factors and study their roles in cell cycle regulation, we performed mRNA differential display analysis of U251 cells in the presence or absence of serum and cloned a novel gene encoding the human mitochondrial transcription termination factor-like protein (mTERFL). The full-length mTERFL cDNA has been isolated and the genomic structure determined. The mTERFL gene consists of three exons and encodes 385 amino acids with 52% sequence similarity to the human mitochondrial transcription termination factor (mTERF). However, mTERFL and mTERF have an opposite expression pattern in response to serum. The expression of mTERFL is dramatically inhibited by the addition of serum in serum-starved cells while the mTERF is rather induced. Northern blot analysis detected three mTERFL transcripts of 1.7, 3.2, and 3.5 kb. Besides the 3.2 kb transcript that is unique to skeletal muscle, other two transcripts express predominant in heart, liver, pancreas, and skeletal muscle. Expression of the GFP-mTERFL fusion protein in HeLa cells localized it to the mitochondria. Furthermore, ectopic expression of mTERFL suppresses cell growth and arrests cells in the G1 stage demonstrated by MTT and flow cytometry analysis. Collectively, our data suggest that mTERFL is a novel mTERF family member and a serum-inhibitory factor probably participating in the regulation of cell growth through the modulation of mitochondrial transcription

  3. Mitogen-activated protein kinase (MAPK) dynamics determine cell fate in the yeast mating response.

    Li, Yang; Roberts, Julie; AkhavanAghdam, Zohreh; Hao, Nan

    2017-12-15

    In the yeast Saccharomyces cerevisiae , the exposure to mating pheromone activates a prototypic mitogen-activated protein kinase (MAPK) cascade and triggers a dose-dependent differentiation response. Whereas a high pheromone dose induces growth arrest and formation of a shmoo-like morphology in yeast cells, lower pheromone doses elicit elongated cell growth. Previous population-level analysis has revealed that the MAPK Fus3 plays an important role in mediating this differentiation switch. To further investigate how Fus3 controls the fate decision process at the single-cell level, we developed a specific translocation-based reporter for monitoring Fus3 activity in individual live cells. Using this reporter, we observed strikingly different dynamic patterns of Fus3 activation in single cells differentiated into distinct fates. Cells committed to growth arrest and shmoo formation exhibited sustained Fus3 activation. In contrast, most cells undergoing elongated growth showed either a delayed gradual increase or pulsatile dynamics of Fus3 activity. Furthermore, we found that chemically perturbing Fus3 dynamics with a specific inhibitor could effectively redirect the mating differentiation, confirming the causative role of Fus3 dynamics in driving cell fate decisions. MAPKs mediate proliferation and differentiation signals in mammals and are therapeutic targets in many cancers. Our results highlight the importance of MAPK dynamics in regulating single-cell responses and open up the possibility that MAPK signaling dynamics could be a pharmacological target in therapeutic interventions. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  4. Expression, purification and crystallization of Streptococcus dysgalactiae-derived mitogen

    Papageorgiou, Anastassios C., E-mail: tassos.papageorgiou@btk.fi; Saarinen, Susanna; Ramirez-Bartutis, Rosa [Turku Centre for Biotechnology, University of Turku and Åbo Akademi University, Turku 20521 (Finland); Kato, Hidehito; Uchiyama, Takehiko [Department of Microbiology and Immunology, Tokyo Women’s Medical University, 8-1 Kawada-cho, Shinjuku-ku, Tokyo 162-8666 (Japan); Kirikae, Teruo; Miyoshi-Akiyama, Toru [Department of Infectious Diseases, International Medical Center of Japan, 1-21-1 Toyama, Shinjuku-ku, Tokyo 162-8655 (Japan); Turku Centre for Biotechnology, University of Turku and Åbo Akademi University, Turku 20521 (Finland)

    2006-03-01

    S. dysgalactiae-derived mitogen, a superantigen, was crystallized. Crystals diffract to 2.4 Å at a synchrotron-radiation source and belong to space group P3/P3{sub 1}/P3{sub 2}, with unit-cell parameters a = b = 52.7, c = 62.4 Å, γ = 120° and one molecule in the crystallographic asymmetric unit. Superantigens are bacterial or viral toxins with potent immunostimulatory properties. Streptococcus dysgalactiae-derived mitogen, a 25 kDa protein, is a recently discovered superantigen isolated from S. dysgalactiae culture supernatant. Sequence considerations suggest that it belongs to a new superantigen family distinct from other superantigens. The protein was expressed in Escherichia coli cells and purified to homogeneity. Crystals were grown at pH 4.2–4.4 in the presence of 18–20%(w/v) PEG 3350 and 0.4 M lithium nitrate. A complete data set to 2.4 Å resolution was collected from a single crystal at liquid-nitrogen temperatures using synchrotron radiation. The crystals belong to space group P3/P3{sub 1}/P3{sub 2}, with unit-cell parameters a = b = 52.7, c = 62.4 Å, γ = 120° and one molecule in the crystallographic asymmetric unit.

  5. Radiosensitivity of angiogenic and mitogenic factors in human amniotic membrane

    Deocaris, Custer C.; De Guzman, Zenaida M.; Deocaris, Chester C.; Jacinto, Sonia D.

    2003-01-01

    Amniotic membrane as a temporary biological dressing remains as a beneficial and cost-effective means of treating burns in developing countries. This medical application is attributed mainly to placental structural and biochemical features that are important for maintaining proper embryonic development. Since fresh amnions are nevertheless for straightforward clinical use and for preservation, radiation-sterilization is been performed to improve the safety of this placental material. However, like any other sterilization method, gamma-radiation may induce physical and chemical changes that may influence the biological property of the material. Thus, the aim of this study is to compare the effects of various levels of radiation-sterilization protocols for human amnions on angiogenic (neovascularization) and epithelial-mitogenic activities, both of which are physiological processes fundamental to wound healing. Water-soluble extract of non-irradiated amnions demonstrates a strong stimulatory effect on both cell proliferation and angiogenesis. No change in biological activity is seen in amnions irradiated at 25 kGy, the sterilization dose used by the Philippine Nuclear Research Institute (PNRI) for the production of radiation-sterilized human amniotic membranes (RSHAM). However, it appears that amniotic angiogenic factors are more radiosensitive than its mitogenic components, evident from the depressed vascularization of the chorioallantoic membrane (CAM) exposed to 35 kGy-irradiated amnions. The dose of 35 kGy is at present the medical sterilization dose used at the Central Tissue Bank in Warsaw (Poland) for the preparation of their amnion allografts. (Authors)

  6. Expression, purification and crystallization of Streptococcus dysgalactiae-derived mitogen

    Papageorgiou, Anastassios C.; Saarinen, Susanna; Ramirez-Bartutis, Rosa; Kato, Hidehito; Uchiyama, Takehiko; Kirikae, Teruo; Miyoshi-Akiyama, Toru

    2006-01-01

    S. dysgalactiae-derived mitogen, a superantigen, was crystallized. Crystals diffract to 2.4 Å at a synchrotron-radiation source and belong to space group P3/P3 1 /P3 2 , with unit-cell parameters a = b = 52.7, c = 62.4 Å, γ = 120° and one molecule in the crystallographic asymmetric unit. Superantigens are bacterial or viral toxins with potent immunostimulatory properties. Streptococcus dysgalactiae-derived mitogen, a 25 kDa protein, is a recently discovered superantigen isolated from S. dysgalactiae culture supernatant. Sequence considerations suggest that it belongs to a new superantigen family distinct from other superantigens. The protein was expressed in Escherichia coli cells and purified to homogeneity. Crystals were grown at pH 4.2–4.4 in the presence of 18–20%(w/v) PEG 3350 and 0.4 M lithium nitrate. A complete data set to 2.4 Å resolution was collected from a single crystal at liquid-nitrogen temperatures using synchrotron radiation. The crystals belong to space group P3/P3 1 /P3 2 , with unit-cell parameters a = b = 52.7, c = 62.4 Å, γ = 120° and one molecule in the crystallographic asymmetric unit

  7. Growth

    John R. Jones; George A. Schier

    1985-01-01

    This chapter considers aspen growth as a process, and discusses some characteristics of the growth and development of trees and stands. For the most part, factors affecting growth are discussed elsewhere, particularly in the GENETICS AND VARIATION chapter and in chapters in PART 11. ECOLOGY. Aspen growth as it relates to wood production is examined in the WOOD RESOURCE...

  8. Cardiac imaging in RASopathies/mitogen activated protein kinase syndromes

    Rita Gravino

    2014-07-01

    Full Text Available RASopathies include a spectrum of disorders due to dysregulation of RAS/mitogen activated protein kinase pathway that plays an essential role in the control of the cell cycle and differentiation. As a consequence, its dysregulation has profound developmental consequences, in particular cardiac malformations. RASopathies with cardiac features are: Noonan syndrome, multiple lentigines syndrome, cardio-faciocutaneous syndrome, Costello syndrome, neurofibromatosis- 1, Legius syndrome, neurofibromatosis- Noonan syndrome. The former syndromes are associated with a high rate of cardiac involvement (60-85% and 12 genes: PTPN11, SOS1, RAF1, KRAS, HRAS, BRAF, MEK1/MAP2K1, MEK2/MAP2K2, NRAS, SHOC2, CBL and SPRED1. Although the majority of these diseases are readily distinguishable in clinical terms, an integrated imaging study of the cardiac condition associated to RASopathies helps to better define risk assessment, surveillance, and management of these patients.

  9. The epidermal growth factor-like domains of the human EMR2 receptor mediate cell attachment through chondroitin sulfate glycosaminoglycans

    Stacey, Martin; Chang, Gin-Wen; Davies, John Q.; Kwakkenbos, Mark J.; Sanderson, Ralph D.; Hamann, Jörg; Gordon, Siamon; Lin, Hsi-Hsien

    2003-01-01

    Using multivalent protein probes, an evolutionarily conserved endogenous ligand for EMR2, a human myeloid cell-restricted EGF-TM7 receptor, was identified on the surface of a number of adherent cell lines. In addition, in situ staining of the ligand has revealed specific in vivo patterns consistent

  10. Cellular reprogramming through mitogen-activated protein kinases

    Justin eLee

    2015-10-01

    Full Text Available Mitogen-activated protein kinase (MAPK cascades are conserved eukaryote signaling modules where MAPKs, as the final kinases in the cascade, phosphorylate protein substrates to regulate cellular processes. While some progress in the identification of MAPK substrates has been made in plants, the knowledge on the spectrum of substrates and their mechanistic action is still fragmentary. In this focused review, we discuss the biological implications of the data in our original paper (Sustained mitogen-activated protein kinase activation reprograms defense metabolism and phosphoprotein profile in Arabidopsis thaliana; Frontiers in Plant Science 5: 554 in the context of related research. In our work, we mimicked in vivo activation of two stress-activated MAPKs, MPK3 and MPK6, through transgenic manipulation of Arabidopsis thaliana and used phosphoproteomics analysis to identify potential novel MAPK substrates. Here, we plotted the identified putative MAPK substrates (and downstream phosphoproteins as a global protein clustering network. Based on a highly stringent selection confidence level, the core networks highlighted a MAPK-induced cellular reprogramming at multiple levels of gene and protein expression – including transcriptional, post-transcriptional, translational, post-translational (such as protein modification, folding and degradation steps, and also protein re-compartmentalization. Additionally, the increase in putative substrates/phosphoproteins of energy metabolism and various secondary metabolite biosynthesis pathways coincides with the observed accumulation of defense antimicrobial substances as detected by metabolome analysis. Furthermore, detection of protein networks in phospholipid or redox elements suggests activation of downstream signaling events. Taken in context with other studies, MAPKs are key regulators that reprogram cellular events to orchestrate defense signaling in eukaryotes.

  11. [Identification of an auxin response factor-like protein cDNA from mango cotyledon section].

    Xiao, Jie-Ning; Huang, Xue-Lin; Huang, Xia; Li, Xiao-Ju

    2004-01-01

    Auxin-responsive elements (AuxRE) interact with a new class of plant-specific transcription factors, auxin response factors (ARFs). Some of ARFs have been shown to repress or activate expression of genes with an AuxRE promotor element. In Arabidopsis, ARFs play important roles in early embryo development and vascular strand formation (ARF5), floral patterning (ARF3) and photo- and gravitropic responses (ARF7). Two cut surfaces (distal and proximal) of mango (Mangifera indica L. var. Zi-Hua) cotyledon showed different patterns of adventitious root formation, with only the proximal cut surface, but not the distal one, could be induced to form the roots. Thus, the mango cotyledon is a good system for studying adventitious root formation. A cDNA fragment homologous to the Arabidopsis auxin response factor-like protein and relates to adventitious root formation from the cut sections were isolated using suppressive subtractive hybridization (SSH). Two cDNA clones, designated as MiARF1 (mango auxin response factor 1 gene, GenBank accession number AY255705) and MiARF2 (mango auxin response factor 2 gene, GenBank accession number is AY300808), were identified by 3'RACE. MiARF1, 3 272bp long, contains an open reading frame (ORF) of 2 523bp, 5'UTR of 285bp and 3'UTR of 464bp, MiARF2, 1 474bp long, contains an ORF of 981bp, 5' UTR of 285bp and 3'UTR of 208bp. The deduced MiARF1 and MiARF2 are homologues of auxin response factor (ARF) family of transcriptional regulators, and show high similarity to ARF of Arabidopsis in conserved domains. The motifs of MiARF1 EL-WHACAGPL in DBD (DNA binding domain) and GDDPW in IV domain are identical to that of ARF-like protein of Arabidopsis. MiARF2 is identical to MiARF1 in a large part of DBD, but lacks a carboxyl-terminal domain containing conserved motifs III and IV. Virtual Northern blot showed that the expression of MiARF2 was high in rooting tissue of cultured cotyledon sections but low in non-rooting tissue, and the MiARF1 was

  12. Procalcitonin NH2-terminal cleavage peptide has no mitogenic effect on normal human osteoblast-like cells

    Hassager, C.; Bonde, S.K.; Anderson, M.A.; Rink, H.; Spelsberg, T.C.; Riggs, B.L.

    1991-01-01

    The NH2-terminal cleavage peptide of procalcitonin (N-proCT) recently was reported to be a bone cell mitogen. The authors have investigated the effect of N-proCT on the proliferation of normal human cells that have the phenotype of mature osteoblasts (hOB cells). N-proCT treatment for 24, 48, or 96 h in concentrations from 1 nM to 1 microM did not significantly increase [3H]thymidine uptake (means ranged from -19% to 38% of control, no significant differences) in hOB cells (6-10 cell strains per experiment) plated at four different densities. However, the hOB cells responded significantly to treatment with transforming growth factor β (3 ng/ml), bovine insulin (300 micrograms/ml), or 30% fetal calf serum, which were included in all experiments as positive controls. The [3H]thymidine uptake data were confirmed in a direct cell count experiment tested at 96 h. Thus they data do not support the hypothesis that N-proCT is a potent mitogen for normal human osteoblasts

  13. Hypoxia-induced mitogenic factor enhances angiogenesis by promoting proliferation and migration of endothelial cells

    Tong Qiangsong; Zheng Liduan; Li Bo; Wang Danming; Huang Chuanshu; Matuschak, George M.; Li Dechun

    2006-01-01

    Our previous studies have indicated that hypoxia-induced mitogenic factor (HIMF) has angiogenic properties in an in vivo matrigel plug model and HIMF upregulates expression of vascular endothelial growth factor (VEGF) in mouse lungs and cultured lung epithelial cells. However, whether HIMF exerts angiogenic effects through modulating endothelial cell function remains unknown. In this study, mouse aortic rings cultured with recombinant HIMF protein resulted in enhanced vascular sprouting and increased endothelial cell spreading as confirmed by Dil-Ac-LDL uptake, von Willebrand factor and CD31 staining. In cultured mouse endothelial cell line SVEC 4-10, HIMF dose-dependently enhanced cell proliferation, in vitro migration and tubulogenesis, which was not attenuated by SU1498, a VEGFR2/Flk-1 receptor tyrosine kinase inhibitor. Moreover, HIMF stimulation resulted in phosphorylation of Akt, p38 and ERK1/2 kinases in SVEC 4-10 cells. Treatment of mouse aortic rings and SVEC 4-10 cells with LY294002, but not SB203580, PD098059 or U0126, abolished HIMF-induced vascular sprouting and angiogenic responses. In addition, transfection of a dominant-negative mutant of phosphatidylinositol 3-kinase (PI-3K), Δp85, blocked HIMF-induced phosphorylation of Akt, endothelial activation and tubulogenesis. These results indicate that HIMF enhances angiogenesis by promoting proliferation and migration of endothelial cells via activation of the PI-3K/Akt pathways

  14. Mitogen activated protein kinase signaling in the kidney: Target for intervention?

    de Borst, M.H.; Wassef, L.; Kelly, D.J.; van Goor, H.; Navis, Ger Jan

    2006-01-01

    Mitogen activated protein kinases (MAPKs) are intracellular signal transduction molecules, which connect cell-surface receptor signals to intracellular processes. MAPKs regulate a range of cellular activities including cell proliferation, gene expression, apoptosis, cell differentiation and cytokine

  15. Heat- and radiation effects on the hemaglutinating- and mitogenic activity of phytohemaglutinins

    Mancini Filho, J.; Vizeu, D.M.; Lajolo, F.M.

    1975-01-01

    The effect of ionizing radiation on hemaglutinating and mitogenic activity of phytohemaglutinins (PHA) in solution is studied. 10 Krad (electron beam) are neede for the destruction of 50% of the aglutinating capacity. The mitogenic effect is more resistent to irradiation (70 Krad for 50% inactivation) may be because both effects are due to different molecules. Changes were also followed by electrophoresis in polyacrylamida. The resistence to irradiation showed to be exponential function of the concentration of PHA in solution. (author) [pt

  16. Manifestation of radiaton injury of human lymphocytes using PHA mitogenic stimulation in different culture systems

    Horky, J.

    1986-01-01

    The proliferative response of human lymphocytes to phytohemagglutinin in vitro is affected by X-irradiation. Dose-related changes in mitogenic stimulation of irradiated lymphocytes were compared for two culture systems - the cultivation of separated lymphocytes and the cultivation of whole blood. In the whole blood cultures, the proliferative activity of stimulated lyphocytes was markedly and reproducibly depressed by irradiation. An exponential curve could be fitted to the values of mitogenic response within a dose range from 0 to 2.5 Gy with high correlation. In a modified test where the mitogenic stimulus was given after a 24 h delay, depression in the response was even more pronounced. Radiosensitivity of human lymphocytes as determined by means of mitogenic stimulation in the whole blood cultures appears to be a characteristic individual feature. The mean D 37 value of the radiation-induced depression in mitogenic response in a group of 20 healthy donors was 2.5 Gy in the standard test and 2.0 Gy in the test with a delayed mitogenic stimulus. In contrast, the data obtained from separated lymphocyte cultures were characterized by a high degree of test-to-test variability and by much lower radiosensitivity. The possible mechanisms of these distinctive manifestations of the same primary radiation injury are discussed. (author) 3 tabs., 2 figs., 12 refs

  17. Proliferation and mitogenic response to PDGF-BB of fibroblasts isolated from chronic venous leg ulcers is ulcer-age dependent

    Agren, M S; Steenfos, H H; Dabelsteen, S

    1999-01-01

    Several pathophysiologic mechanisms have been proposed to explain slow-healing leg ulcers, but little is known about the growth behavior of cells in these wounds. Platelet-derived growth factor-BB applied topically to chronic wounds has shown beneficial effects, although the effects have been less...... pronounced than would have been expected based on studies on acute wounds. The objective of this study was to compare fibroblasts in culture obtained from chronic wounds (non-healing chronic venous leg ulcers), acute wounds and normal dermis regarding growth, mitogenic response to platelet-derived growth...... chronic wounds have approached or even reached the end of their lifespan (phase III). This might provide one explanation for the non-healing state and therapy resistance to topical platelet-derived growth factor-BB of some venous leg ulcers....

  18. Functional characterization of an alpha-factor-like Sordaria macrospora peptide pheromone and analysis of its interaction with its cognate receptor in Saccharomyces cerevisiae.

    Mayrhofer, Severine; Pöggeler, Stefanie

    2005-04-01

    The homothallic filamentous ascomycete Sordaria macrospora possesses genes which are thought to encode two pheromone precursors and two seven-transmembrane pheromone receptors. The pheromone precursor genes are termed ppg1 and ppg2. The putative products derived from the gene sequence show structural similarity to the alpha-factor precursors and a-factor precursors of the yeast Saccharomyces cerevisiae. Likewise, sequence similarity has been found between the putative products of the pheromone receptor genes pre2 and pre1 and the S. cerevisiae Ste2p alpha-factor receptor and Ste3p a-factor receptor, respectively. To investigate whether the alpha-factor-like pheromone-receptor pair of S. macrospora is functional, a heterologous yeast assay was used. Our results show that the S. macrospora alpha-factor-like pheromone precursor PPG1 is processed into an active pheromone by yeast MATalpha cells. The S. macrospora PRE2 protein was demonstrated to be a peptide pheromone receptor. In yeast MATa cells lacking the endogenous Ste2p receptor, the S. macrospora PRE2 receptor facilitated all aspects of the pheromone response. Using a synthetic peptide, we can now predict the sequence of one active form of the S. macrospora peptide pheromone. We proved that S. macrospora wild-type strains secrete an active pheromone into the culture medium and that disruption of the ppg1 gene in S. macrospora prevents pheromone production. However, loss of the ppg1 gene does not affect vegetative growth or fertility. Finally, we established the yeast assay as an easy and useful system for analyzing pheromone production in developmental mutants of S. macrospora.

  19. In vitro induction of lymphocyte responsiveness by a Strongylus vulgaris-derived mitogen.

    Bailey, M; Lloyd, S; Martin, S C; Soulsby, E J

    1984-01-01

    Proliferation in vitro of peripheral blood lymphocytes both from horses infected with Strongylus vulgaris and from helminth-free ponies was observed in the presence of extracts of the fourth and fifth stage larvae and adults of S. vulgaris. In addition, S. vulgaris extracts induced transformation in cultures of peripheral blood lymphocytes from sheep and dogs and in mouse spleen cell cultures. Nylon wool non-adherent, T cell enriched fractions of lymphocytes from both mice and horses were stimulated by the S. vulgaris larval mitogen while no proliferation was observed in cultures containing nylon wool adherent, B cell enriched fractions. Macrophage co-operation appeared not to be necessary for S. vulgaris mitogen-induced transformation of spleen cells. The S. vulgaris mitogen stimulated a subpopulation of mouse spleen cells different from those responsive to PHA, Con A and LPS. These cells might be T helper cells since B cells were stimulated to proliferate in the presence of both T cells and S. vulgaris larval mitogen. In addition, the supernatant of in vitro cultured larvae of S. vulgaris induced slight, but significant transformation of equine peripheral blood lymphocytes. Therefore, it is possible that the S. vulgaris mitogen released by both viable parasites and degenerating larvae might induce T cell dependent production of immunoglobulin in vivo and account for the beta-globulinaemia, of which IgG(T) is a major component, in S vulgaris infected horses.

  20. Effects of cyclophosphamide on in vitro human lymphocyte culture and mitogenic stimulation

    Sharma, B.S.

    1983-01-01

    Cyclophosphamide (CY) has been reported to be inactive in vitro under certain conditions. In the present study, CY was tested for its ability to inhibit human lymphocyte proliferation and to modulate lymphocyte response to mitogens in vitro. The inhibition of or the increase in 3 H-thymidine incorporation in mitogen-stimulated and unstimulated lymphocytes by CY was used as a measure of CY activity in vitro. The results demonstrate that lymphocytes from 10 different persons had a mean decrease of 74% in 3 H-thymidine incorporation in the presence of CY (P less than 0.005). The effect was maximal at a concentration of 160 micrograms/ml. A mean inhibition of 35 and 55% was caused by 10 and 40 micrograms/ml concentrations of CY, respectively. CY also was able to reduce the number of viable cells during 5 days in culture and had a profound effect on mitogen stimulation of lymphocytes. In all cases, CY modulated the stimulation of lymphocytes by phytohemagglutinin (PHA), concanavalin A (Con A), and pokeweed mitogen (PWM) either by augmenting or suppressing the responses. At low concentrations (10 micrograms/ml) it augmented mitogenic stimulation by 46 to 281%. At higher concentrations (20 to 160 micrograms/ml), CY had a suppressive effect with a maximum suppression of 99%. The CY-induced immunomodulation is perhaps caused by its action on the regulatory T cells. When tested in vitro, CY had inhibitory activity on T cells

  1. Cocoa Procyanidins Suppress Transformation by Inhibiting Mitogen-activated Protein Kinase Kinase*S⃞

    Kang, Nam Joo; Lee, Ki Won; Lee, Dong Eun; Rogozin, Evgeny A.; Bode, Ann M.; Lee, Hyong Joo; Dong, Zigang

    2008-01-01

    Cocoa was shown to inhibit chemically induced carcinogenesis in animals and exert antioxidant activity in humans. However, the molecular mechanisms of the chemopreventive potential of cocoa and its active ingredient(s) remain unknown. Here we report that cocoa procyanidins inhibit neoplastic cell transformation by suppressing the kinase activity of mitogen-activated protein kinase kinase (MEK). A cocoa procyanidin fraction (CPF) and procyanidin B2 at 5 μg/ml and 40 μm, respectively, inhibited 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced neoplastic transformation of JB6 P+ mouse epidermal (JB6 P+) cells by 47 and 93%, respectively. The TPA-induced promoter activity and expression of cyclooxygenase-2, which is involved in tumor promotion and inflammation, were dose-dependently inhibited by CPF or procyanidin B2. The activation of activator protein-1 and nuclear factor-κB induced by TPA was also attenuated by CPF or procyanidin B2. The TPA-induced phosphorylation of MEK, extracellular signal-regulated kinase, and p90 ribosomal s6 kinase was suppressed by CPF or procyanidin B2. In vitro and ex vivo kinase assay data demonstrated that CPF or procyanidin B2 inhibited the kinase activity of MEK1 and directly bound with MEK1. CPF or procyanidin B2 suppressed JB6 P+ cell transformation induced by epidermal growth factor or H-Ras, both of which are known to be involved in MEK/ERK signal activation. In contrast, theobromine (up to 80 μm) had no effect on TPA-induced transformation, cyclooxygenase-2 expression, the transactivation of activator protein-1 or nuclear factor-κB, or MEK. Notably, procyanidin B2 exerted stronger inhibitory effects compared with PD098059 (a well known pharmacological inhibitor of MEK) on MEK1 activity and neoplastic cell transformation. PMID:18519570

  2. Mitogen-activated protein kinase phosphatase (MKP)-1 as a neuroprotective agent: promotion of the morphological development of midbrain dopaminergic neurons.

    Collins, Louise M; O'Keeffe, Gerard W; Long-Smith, Caitriona M; Wyatt, Sean L; Sullivan, Aideen M; Toulouse, André; Nolan, Yvonne M

    2013-06-01

    A greater understanding of the mechanisms that promote the survival and growth of dopaminergic neurons is essential for the advancement of cell replacement therapies for Parkinson's disease (PD). Evidence supports a role for the mitogen-activated protein kinase p38 in the demise of dopaminergic neurons, while mitogen-activated protein kinase phosphatase-1 (MKP-1), which negatively regulates p38 activity, has not yet been investigated in this context. Here, we show that MKP-1 is expressed in dopaminergic neurons cultured from E14 rat ventral mesencephalon (VM). When dopaminergic neurons were transfected to overexpress MKP-1, they displayed a more complex morphology than their control counterparts in vitro. Specifically, MKP-1-transfection induced significant increases in neurite length and branching with a maximum increase observed in primary branches. We demonstrate that inhibition of dopaminergic neurite growth induced by treatment of rat VM neurons with the dopaminergic neurotoxin 6-hydroxydopamine (6-OHDA) in vitro is mediated by p38 and is concomitant with a significant and selective decrease in MKP-1 expression in these neurons. We further show that overexpression of MKP-1 in dopaminergic neurons contributes to neuroprotection against the effects of 6-OHDA. Collectively, we report that MKP-1 can promote the growth and elaboration of dopaminergic neuronal processes and can help protect them from the neurotoxic effects of 6-OHDA. Thus, we propose that strategies aimed at augmenting MKP-1 expression or activity may be beneficial in protecting dopaminergic neurons and may provide potential therapeutic approaches for PD.

  3. Stimulated mitogen-activated protein kinase is necessary but not sufficient for the mitogenic response to angiotensin II. A role for phospholipase D.

    Wilkie, N; Morton, C; Ng, L L; Boarder, M R

    1996-12-13

    Activation of the mitogen-activated protein kinase (MAPK) cascade has been widely associated with cell proliferation; previous studies have shown that angiotensin II (AII), acting on 7-transmembrane G protein-coupled receptors, stimulates the MAPK pathway. In this report we investigate whether the MAPK pathway is required for the mitogenic response to AII stimulation of vascular smooth muscle cells derived from the hypertensive rat (SHR-VSM). AII stimulates the phosphorylation of MAPK, as determined by Western blot specific for the tyrosine 204 phosphorylated form of the protein. This MAPK phosphorylation was inhibited by the presence of the inhibitor of MAPK kinase activation, PD 098059. Using a peptide kinase assay shown to measure the p42 and p44 isoforms of MAPK, the stimulated response to AII was inhibited by PD 098059 with an IC50 of 15.6 +/- 1.6 microM. The AII stimulation of [3H]thymidine incorporation was inhibited by PD 098059 with an IC50 of 17.8 +/- 3.1 microM. PD 098059 had no effect on AII-stimulated phospholipase C or phospholipase D (PLD) activity. When the SHR-VSM cells were stimulated with phorbol ester, there was an activation of MAPK similar in size and duration to the response to AII, but there was no significant enhancement of [3H]thymidine incorporation. There was also no activation of PLD by phorbol ester, while AII produced a robust PLD response. Diversion of the product of the PLD reaction by 1-butanol caused a partial loss of the [3H]thymidine response; this did not occur with tertiary butanol, which did not interfere with the PLD reaction. These results show that in these cells the MAPK cascade is required but not sufficient for the mitogenic response to AII, and suggest that the full mitogenic response requires both MAPK in conjunction with other signaling components, one of which is PLD.

  4. Induced overexpression of protein kinase D1 stimulates mitogenic signaling in human pancreatic carcinoma PANC-1 cells.

    Kisfalvi, Krisztina; Hurd, Cliff; Guha, Sushovan; Rozengurt, Enrique

    2010-05-01

    Neurotensin (NT) stimulates protein kinase D1 (PKD1), extracellular signal regulated kinase (ERK), c-Jun N-terminal Kinase (JNK), and DNA synthesis in the human pancreatic adenocarcinoma cell line PANC-1. To determine the effect of PKD1 overexpression on these biological responses, we generated inducible stable PANC-1 clones that express wild-type (WT) or kinase-dead (K618N) forms of PKD1 in response to the ecdysone analog ponasterone-A (PonA). NT potently stimulated c-Jun Ser(63) phosphorylation in both wild type and clonal derivatives of PANC-1 cells. PonA-induced expression of WT, but not K618N PKD1, rapidly blocked NT-mediated c-Jun Ser(63) phosphorylation either at the level of or upstream of MKK4, a dual-specificity kinase that leads to JNK activation. This is the first demonstration that PKD1 suppresses NT-induced JNK/cJun activation in PANC-1 cells. In contrast, PKD1 overexpression markedly increased the duration of NT-induced ERK activation in these cells. The reciprocal influence of PKD1 signaling on pro-mitogenicERK and pro-apopotic JNK/c-Jun pathways prompted us to examine whether PKD1 overexpression promotes DNA synthesis and proliferation of PANC-1 cells. Our results show that PKD1 overexpression increased DNA synthesis and cell numbers of PANC-1 cells cultured in regular dishes or in polyhydroxyethylmethacrylate [Poly-(HEMA)]-coated dishes to eliminate cell adhesion (anchorage-independent growth). Furthermore, PKD1 overexpression markedly enhanced DNA synthesis induced by NT (1-10 nM). These results indicate that PKD1 mediates mitogenic signaling in PANC-1 and suggests that this enzyme could be a novel target for the development of therapeutic drugs that restrict the proliferation of these cells.

  5. Precipitin response of the mitogen produced by Strongylus vulgaris arterial larvae.

    Adeyefa, C A

    1992-07-01

    The precipitin response of the mitogen produced by Strongylus vulgaris arterial larvae was investigated. IgG (T) from the sera of horses naturally infected with S. vulgaris adults and arterial larvae recognised the presence of two antigenic components of the mitogenic fractions. The results obtained seem to confirm that these antigens are immunogenic in stimulating the production of increased levels of IgG(T) in infected animals, and showed that the procedures could be used as immunological tools in the diagnosis of S. vulgaris infection.

  6. p38 Mitogen-Activated Protein Kinase in Metastasis Associated with Transforming Growth Factor Beta

    2006-06-01

    23): 12. sis--correlation in invasive breast carcinoma. N ppendices Rep 2. Dumont, N., A.V. Bakin, and C.L. Arteaga...Y. W. Nrf2 is essential for protection against acute pulmonary injury in mice. Proc. Natl. Acad. Sci. USA 96: 12731–12736; 1999. [15] Enomoto, A...proteomic analysis of all-trans-retinoic acid treatment reveals system- atic post-transcriptional control mechanisms in acute promyelocytic leukemia. Blood

  7. Regulation of mitogen-activated protein kinase 3/1 activity during meiosis resumption in mammals

    Procházka, Radek; Blaha, Milan

    2015-01-01

    Roč. 61, č. 6 (2015), s. 495-502 ISSN 0916-8818 R&D Projects: GA MZe(CZ) QJ1510138 Institutional support: RVO:67985904 Keywords : cumulus oocyte complexes * meiosis resumption * mitogen-activated protein kinase 3/1 (MAPK3/1) Subject RIV: GI - Animal Husbandry ; Breeding Impact factor: 1.453, year: 2015

  8. Insulin resistance enhances the mitogen-activated protein kinase signaling pathway in ovarian granulosa cells.

    Linghui Kong

    Full Text Available The ovary is the main regulator of female fertility. Granulosa cell dysfunction may be involved in various reproductive endocrine disorders. Here we investigated the effect of insulin resistance on the metabolism and function of ovarian granulosa cells, and dissected the functional status of the mitogen-activated protein kinase signaling pathway in these cells. Our data showed that dexamethasone-induced insulin resistance in mouse granulosa cells reduced insulin sensitivity, accompanied with an increase in phosphorylation of p44/42 mitogen-activated protein kinase. Furthermore, up-regulation of cytochrome P450 subfamily 17 and testosterone and down-regulation of progesterone were observed in insulin-resistant mouse granulosa cells. Inhibition of p44/42 mitogen-activated protein kinase after induction of insulin resistance in mouse granulosa cells decreased phosphorylation of p44/42 mitogen-activated protein kinase, downregulated cytochrome P450 subfamily 17 and lowered progesterone production. This insulin resistance cell model can successfully demonstrate certain mechanisms such as hyperandrogenism, which may inspire a new strategy for treating reproductive endocrine disorders by regulating cell signaling pathways.

  9. DMPD: Manipulation of mitogen-activated protein kinase/nuclear factor-kappaB-signalingcascades during intracellular Toxoplasma gondii infection. [Dynamic Macrophage Pathway CSML Database

    Full Text Available 15361242 Manipulation of mitogen-activated protein kinase/nuclear factor-kappaB-sig...mmunol Rev. 2004 Oct;201:191-205. (.png) (.svg) (.html) (.csml) Show Manipulation of mitogen-activated prote... gondii infection. PubmedID 15361242 Title Manipulation of mitogen-activated protein kinase/nuclear factor-k

  10. Mitogenic activity of new lectins from seeds of wild Artocarpus species from Vietnam.

    Blasco, E; Ngoc, L D; Aucouturier, P; Preud'Homme, J L; Barra, A

    1996-05-01

    Proliferative response of human peripheral blood mononuclear cells (PBMC) stimulated by new lectins purified from seeds of differents Artocarpus species from Vietnam (A. asperulus, A. heterophyllus, A. masticata, A. melinoxylus, A. parva and A. petelotii) was studied and compared to those of the lectin jacalin purified from jackfruit (A. heterophyllus) seeds collected in the island La Réunion. All lectins stimulated human PBMC to proliferate, with a variable efficiency of the mitogenic activity. Phenotypic analysis of cells recovered after 7 day-cultures showed that these lectins mostly stimulated CD4+ T lymphocytes. These results suggest that these lectins from different Artocarpus species are similar in terms of their mitogenic activity although their structural features are not identical.

  11. Recruitment of focal adhesion kinase and paxillin to β1 integrin promotes cancer cell migration via mitogen activated protein kinase activation

    Crowe, David L; Ohannessian, Arthur

    2004-01-01

    Integrin-extracellular matrix interactions activate signaling cascades such as mitogen activated protein kinases (MAPK). Integrin binding to extracellular matrix increases tyrosine phosphorylation of focal adhesion kinase (FAK). Inhibition of FAK activity by expression of its carboxyl terminus decreases cell motility, and cells from FAK deficient mice also show reduced migration. Paxillin is a focal adhesion protein which is also phosphorylated on tyrosine. FAK recruitment of paxillin to the cell membrane correlates with Shc phosphorylation and activation of MAPK. Decreased FAK expression inhibits papilloma formation in a mouse skin carcinogenesis model. We previously demonstrated that MAPK activation was required for growth factor induced in vitro migration and invasion by human squamous cell carcinoma (SCC) lines. Adapter protein recruitment to integrin subunits was examined by co-immunoprecipitation in SCC cells attached to type IV collagen or plastic. Stable clones overexpressing FAK or paxillin were created using the lipofection technique. Modified Boyden chambers were used for invasion assays. In the present study, we showed that FAK and paxillin but not Shc are recruited to the β1 integrin cytoplasmic domain following attachment of SCC cells to type IV collagen. Overexpression of either FAK or paxillin stimulated cancer cell migration on type IV collagen and invasion through reconstituted basement membrane which was dependent on MAPK activity. We concluded that recruitment of focal adhesion kinase and paxillin to β1 integrin promoted cancer cell migration via the mitogen activated protein kinase pathway

  12. Recruitment of focal adhesion kinase and paxillin to β1 integrin promotes cancer cell migration via mitogen activated protein kinase activation

    Ohannessian Arthur

    2004-05-01

    Full Text Available Abstract Background Integrin-extracellular matrix interactions activate signaling cascades such as mitogen activated protein kinases (MAPK. Integrin binding to extracellular matrix increases tyrosine phosphorylation of focal adhesion kinase (FAK. Inhibition of FAK activity by expression of its carboxyl terminus decreases cell motility, and cells from FAK deficient mice also show reduced migration. Paxillin is a focal adhesion protein which is also phosphorylated on tyrosine. FAK recruitment of paxillin to the cell membrane correlates with Shc phosphorylation and activation of MAPK. Decreased FAK expression inhibits papilloma formation in a mouse skin carcinogenesis model. We previously demonstrated that MAPK activation was required for growth factor induced in vitro migration and invasion by human squamous cell carcinoma (SCC lines. Methods Adapter protein recruitment to integrin subunits was examined by co-immunoprecipitation in SCC cells attached to type IV collagen or plastic. Stable clones overexpressing FAK or paxillin were created using the lipofection technique. Modified Boyden chambers were used for invasion assays. Results In the present study, we showed that FAK and paxillin but not Shc are recruited to the β1 integrin cytoplasmic domain following attachment of SCC cells to type IV collagen. Overexpression of either FAK or paxillin stimulated cancer cell migration on type IV collagen and invasion through reconstituted basement membrane which was dependent on MAPK activity. Conclusions We concluded that recruitment of focal adhesion kinase and paxillin to β1 integrin promoted cancer cell migration via the mitogen activated protein kinase pathway.

  13. Increased rate of repair of ultraviolet-induced DNA strand breaks in mitogen stimulated lymphocytes

    Hamlet, S.M.; Lavin, M.F.; Jennings, P.A. (Queensland Univ., St. Lucia (Australia). Dept. of Biochemistry; Queensland Univ., St. Lucia (Australia). Dept. of Veterinary Pathology; Queensland Univ. St. Lucia (Australia). Dept. of Public Health)

    1982-05-01

    Previous results have shown that phytohaemagglutinin-stimulated bovine lymphocytes exhibit a peak of ultraviolet-induced DNA repair synthesis 3 to 4 days after addition of mitogen. The level of repair synthesis was approximately tenfold higher than that in unstimulated lymphocytes. These studies have been extended to examine the rate of repair of strand breaks in U.V.-irradiated bovine lymphocytes. The extent of breakage of DNA was shown to be the same in mitogen-stimulated and unstimulated lymphocytes from two breeds of cattle, when determined by sedimentation of nucleoids on sucrose gradients. However, in mitogen-stimulated cells the time taken to repair DNA strand breaks was 6 hours compared with 12 hours in stationary phase lymphocytes after a U.V. dose of 5 J/m/sup 2/. These results suggest that the increased rate of repair of strand breaks is due to the induction of enzymes involved at the post-incision stage of DNA repair. Thus the increased level of repair synthesis observed in earlier work correlates with an increased rate of repair of DNA strand breaks in phytohaemagglutinin-stimulated bovine lymphocytes.

  14. Increased rate of repair of ultraviolet-induced DNA strand breaks in mitogen stimulated lymphocytes

    Hamlet, S.M.; Lavin, M.F.; Jennings, P.A.; Queensland Univ., St. Lucia; Queensland Univ. St. Lucia

    1982-01-01

    Previous results have shown that phytohaemagglutinin-stimulated bovine lymphocytes exhibit a peak of ultraviolet-induced DNA repair synthesis 3 to 4 days after addition of mitogen. The level of repair synthesis was approximately tenfold higher than that in unstimulated lymphocytes. These studies have been extended to examine the rate of repair of strand breaks in U.V.-irradiated bovine lymphocytes. The extent of breakage of DNA was shown to be the same in mitogen-stimulated and unstimulated lymphocytes from two breeds of cattle, when determined by sedimentation of nucleoids on sucrose gradients. However, in mitogen-stimulated cells the time taken to repair DNA strand breaks was 6 hours compared with 12 hours in stationary phase lymphocytes after a U.V. dose of 5 J/m 2 . These results suggest that the increased rate of repair of strand breaks is due to the induction of enzymes involved at the post-incision stage of DNA repair. Thus the increased level of repair synthesis observed in earlier work correlates with an increased rate of repair of DNA strand breaks in phytohaemagglutinin-stimulated bovine lymphocytes. (author)

  15. Mitogenic activation of B cells in vitro: the properties of adherent accessory cells as revealed by partition analysis

    Kettman, J.R.; Soederberg, A.; Lefkovits, I.

    1986-08-15

    The requirement of B cells activated by mitogen (dextran sulfate plus lipopolysaccharide) for accessory cells was studied by partition analysis. Small numbers of splenic B cells were activated to clonal growth, as determined by visual inspection, and to immunoglobulin (Ig) synthesis, as determined by release of Ig into the culture fluid. By placing irradiated adherent cells in the periphery of the microculture wells and forcing responding cells to different areas of the well (slant experiments), it was observed that no cell contact was necessary for B cell activation, and that promoted contact (Rock and Roll experiments) does not increase the efficiency of activation. Sequential microcultures suggest that only some irradiated adherent cells act as accessory cells, but they can perform this function to more than one B cell. Attempts to perform limiting dilution analysis by varying irradiated adherent cell input showed non-single-hit behavior. When the data were rearranged, taking into account the distribution of irradiated adherent cells, then single-hit behavior with about 1 to 5% of irradiated adherent cells acting as an accessory cells for B cell clonal activation was observed. The evidence suggests that an uncommon irradiated adherent cell releases a soluble factor necessary for B cell activation and/or clonal proliferation.

  16. SMALL GRAIN 1, which encodes a mitogen-activated protein kinase kinase 4, influences grain size in rice.

    Duan, Penggen; Rao, Yuchun; Zeng, Dali; Yang, Yaolong; Xu, Ran; Zhang, Baolan; Dong, Guojun; Qian, Qian; Li, Yunhai

    2014-02-01

    Although grain size is one of the most important components of grain yield, little information is known about the mechanisms that determine final grain size in crops. Here we characterize rice small grain1 (smg1) mutants, which exhibit small and light grains, dense and erect panicles and comparatively slightly shorter plants. The short grain and panicle phenotypes of smg1 mutants are caused by a defect in cell proliferation. The smg1 mutations were identified, using a map-based cloning approach, in mitogen-activated protein kinase kinase 4 (OsMKK4). Relatively higher expression of OsMKK4/SMG1 was detected in younger organs than in older ones, consistent with its role in cell proliferation. Green fluorescent protein (GFP)-OsMKK4/SMG1 fusion proteins appear to be distributed ubiquitously in plant cells. Further results revealed that OsMKK4 influenced brassinosteroid (BR) responses and the expression of BR-related genes. Thus, our findings have identified OsMKK4 as a factor for grain size, and suggest a possible link between the MAPK pathways and BRs in grain growth. © 2013 The Authors The Plant Journal © 2013 John Wiley & Sons Ltd.

  17. Mitogenic activation of B cells in vitro: the properties of adherent accessory cells as revealed by partition analysis

    Kettman, J.R.; Soederberg, A.; Lefkovits, I.

    1986-01-01

    The requirement of B cells activated by mitogen (dextran sulfate plus lipopolysaccharide) for accessory cells was studied by partition analysis. Small numbers of splenic B cells were activated to clonal growth, as determined by visual inspection, and to immunoglobulin (Ig) synthesis, as determined by release of Ig into the culture fluid. By placing irradiated adherent cells in the periphery of the microculture wells and forcing responding cells to different areas of the well (slant experiments), it was observed that no cell contact was necessary for B cell activation, and that promoted contact (Rock and Roll experiments) does not increase the efficiency of activation. Sequential microcultures suggest that only some irradiated adherent cells act as accessory cells, but they can perform this function to more than one B cell. Attempts to perform limiting dilution analysis by varying irradiated adherent cell input showed non-single-hit behavior. When the data were rearranged, taking into account the distribution of irradiated adherent cells, then single-hit behavior with about 1 to 5% of irradiated adherent cells acting as an accessory cells for B cell clonal activation was observed. The evidence suggests that an uncommon irradiated adherent cell releases a soluble factor necessary for B cell activation and/or clonal proliferation

  18. KFC, a Ste20-like kinase with mitogenic potential and capability to activate the SAPK/JNK pathway.

    Yustein, J T; Li, D; Robinson, D; Kung, H J

    2000-02-03

    The Sterile-20 (Ste20) family of serine-threonine kinases has been implicated in the activation of the stress-activated protein kinase pathways. However, the physiological role has remained ambiguous for most of the investigated mammalian Ste20's. Here we report the cloning of a novel Ste20-like kinase, from chicken embryo fibroblast (CEF) cells, which we have named KFC, for Kinase From Chicken. The 898 amino acid full-length KFC protein contains an amino-terminal kinase domain, an adjacent downstream serine-rich region, and a C-terminal tail containing a coiled-coil domain. Here we show that the coiled-coil domain of KFC negatively regulates the intrinsic kinase activity. We have also identified a splice variant of KFC in which there is a 207 nucleotide in-frame deletion. This deletion of 69 amino acids encompasses the serine-rich region. These two isoforms, called KFCL, for full-length, and KFCS for spliced (or short) form, not only differ in structure, but also in biological properties. Stable CEF cells overexpressing KFCL, but not KFCS, have a significant increase in growth rate when compared to parental cells. This mitogenic effect is the first such reported for this family of kinases. Finally, we found that KFC, when activated by truncation of the regulatory C-terminus, has a specific activation of the stress-activated protein kinase (SAPK/JNK) pathway.

  19. Novel Mitogen-Activated Protein Kinase MpkC of Aspergillus fumigatus Is Required for Utilization of Polyalcohol Sugars▿

    Reyes, Guadalupe; Romans, Angela; Nguyen, C. Kim; May, Gregory S.

    2006-01-01

    The genome of Aspergillus fumigatus has four genes that encode mitogen-activated protein kinases (MAPKs), sakA/hogA, mpkA, mpkB, and mpkC. The functions of the MpkB and MpkC MAPKs are unknown for A. fumigatus and the closely related and genetically amenable species Aspergillus nidulans. mpkC deletion mutants of A. fumigatus were made and their phenotypes characterized. The mpkC deletion mutants were viable and had normal conidial germination and hyphal growth on minimal or complete media. This is in contrast to deletion mutants with deletions in the closely related MAPK gene sakA/hogA that we previously reported had a nitrogen source-dependent germination phenotype. Similarly, the growth of the mpkC deletion mutants was wild type on high-osmolarity medium. Consistent with these two MAP kinase genes regulating different cellular responses, we determined that the mpkC deletion mutants were unable to grow on minimal medium with sorbitol or mannitol as the sole carbon source. This result implicates MpkC signaling in carbon source utilization. Changes in mRNA levels for sakA and mpkC were measured in response to hypertonic stress, oxidative stress, and a shift from glucose to sorbitol to determine if there was overlap in the SakA and MpkC signaling pathways. These studies demonstrated that SakA- and MpkC-dependent patterns of change in mRNA levels are distinct and have minimal overlap in response to these environmental stresses. PMID:16998074

  20. Novel mitogen-activated protein kinase MpkC of Aspergillus fumigatus is required for utilization of polyalcohol sugars.

    Reyes, Guadalupe; Romans, Angela; Nguyen, C Kim; May, Gregory S

    2006-11-01

    The genome of Aspergillus fumigatus has four genes that encode mitogen-activated protein kinases (MAPKs), sakA/hogA, mpkA, mpkB, and mpkC. The functions of the MpkB and MpkC MAPKs are unknown for A. fumigatus and the closely related and genetically amenable species Aspergillus nidulans. mpkC deletion mutants of A. fumigatus were made and their phenotypes characterized. The mpkC deletion mutants were viable and had normal conidial germination and hyphal growth on minimal or complete media. This is in contrast to deletion mutants with deletions in the closely related MAPK gene sakA/hogA that we previously reported had a nitrogen source-dependent germination phenotype. Similarly, the growth of the mpkC deletion mutants was wild type on high-osmolarity medium. Consistent with these two MAP kinase genes regulating different cellular responses, we determined that the mpkC deletion mutants were unable to grow on minimal medium with sorbitol or mannitol as the sole carbon source. This result implicates MpkC signaling in carbon source utilization. Changes in mRNA levels for sakA and mpkC were measured in response to hypertonic stress, oxidative stress, and a shift from glucose to sorbitol to determine if there was overlap in the SakA and MpkC signaling pathways. These studies demonstrated that SakA- and MpkC-dependent patterns of change in mRNA levels are distinct and have minimal overlap in response to these environmental stresses.

  1. Parameters of the labeling of mitogen-activated murine lymphocytes by [35S]methionine for two-dimensional gel electrophoresis. I

    Kettman, J.R.

    1986-01-01

    Labeling with [ 35 S]methionine at a high specific activity is essential to the facile preparation of 2-dimensional gel electrophoretograms with the analytical 2-dimensional charge-size separation procedure. Mitogen-activated T and B lymphocytes subjected to low methionine concentrations would not proceed through cell cycle. In the case of activated B lymphocytes, the use of fetal bovine serum, dialyzed to lower endogenous methionine concentrations, prevented B cell growth even in the presence of otherwise satisfactory levels of methionine. High concentrations of [ 35 S]methionine induced B cell death, apparently by radiation damage. Despite these problems, good radioautograms and radiofluorograms of 2D electrophoretograms could be prepared by labeling activated B or T cells in bulk with high specific activity [ 35 S]methionine. (Auth.)

  2. Genome-wide identification of mitogen-activated protein kinase gene family in Gossypium raimondii and the function of their corresponding orthologs in tetraploid cultivated cotton.

    Zhang, Xueying; Wang, Liman; Xu, Xiaoyang; Cai, Caiping; Guo, Wangzhen

    2014-12-10

    Mitogen-activated protein kinase (MAPK) cascades play a crucial role in plant growth and development as well as biotic and abiotic stress responses. Knowledge about the MAPK gene family in cotton is limited, and systematic investigation of MAPK family proteins has not been reported. By performing a bioinformatics homology search, we identified 28 putative MAPK genes in the Gossypium raimondii genome. These MAPK members were anchored onto 11 chromosomes in G. raimondii, with uneven distribution. Phylogenetic analysis showed that the MAPK candidates could be classified into the four known A, B, C and D groups, with more MAPKs containing the TEY phosphorylation site (18 members) than the TDY motif (10 members). Furthermore, 21 cDNA sequences of MAPKs with complete open reading frames (ORFs) were identified in G. hirsutum via PCR-based approaches, including 13 novel MAPKs and eight with homologs reported previously in tetraploid cotton. The expression patterns of 23 MAPK genes reveal their important roles in diverse functions in cotton, in both various developmental stages of vegetative and reproductive growth and in the stress response. Using a reverse genetics approach based on tobacco rattle virus-induced gene silencing (TRV-VIGS), we further verified that MPK9, MPK13 and MPK25 confer resistance to defoliating isolates of Verticillium dahliae in cotton. Silencing of MPK9, MPK13 and MPK25 can significantly enhance cotton susceptibility to this pathogen. This study presents a comprehensive identification of 28 mitogen-activated protein kinase genes in G. raimondii. Their phylogenetic relationships, transcript expression patterns and responses to various stressors were verified. This study provides the first systematic analysis of MAPKs in cotton, improving our understanding of defense responses in general and laying the foundation for future crop improvement using MAPKs.

  3. Effect of epidermal growth factor-like peptides on pig cumulus cell expansion, oocyte maturation and acquisition of developmental competence in vitro: comparison with gonadotropins

    Procházka, Radek; Petlach, Michal; Nagyová, Eva; Němcová, Lucie

    2011-01-01

    Roč. 141, č. 4 (2011), s. 425-435 ISSN 1470-1626 R&D Projects: GA ČR GA523/08/0111; GA MZe QI101A166 Institutional research plan: CEZ:AV0Z50450515 Keywords : activatd protein kinase * EGF like factor * meiotic resumption Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.090, year: 2011

  4. Altered epidermal growth factor-like sequences provide evidence for a role of Notch as a receptor in cell fate decisions.

    Heitzler, P; Simpson, P

    1993-03-01

    In Drosophila each neural precursor is chosen from a group of cells through cell interactions mediated by Notch and Delta which may function as receptor and ligand (signal), respectively, in a lateral signalling pathway. The cells of a group are equipotential and express both Notch and Delta. Hyperactive mutant Notch molecules, (Abruptex), probably have an enhanced affinity for the ligand. When adjacent to wild-type cells, cells bearing the Abruptex proteins are unable to produce the signal. It is suggested that in addition to the binding of Notch molecules on one cell to the Delta molecules of opposing cells, the Notch and Delta proteins on the surface of the same cell may interact. Binding between a cell's own Notch and Delta molecules would alter the availability of these proteins to interact with their counterparts on adjacent cells.

  5. The effect of midazolam on neutrophil mitogen-activated protein kinase.

    Ghori, Kamran

    2010-06-01

    Neutrophil p38 mitogen-activated protein kinase (MAPK) is a key enzyme in the intracellular signalling pathway that is responsible for many neutrophil functions, which are important in neutrophil-endothelial interaction. The imidazole compounds are inhibitors of this enzyme system. The objectives of this in-vitro investigation were to examine the effect of midazolam on neutrophil p38 MAPK activation (phosphorylation) following in-vitro ischaemia-reperfusion injury, and the expression of adhesion molecule CD11b\\/CD18.

  6. MitoGen: A Framework for Generating 3D Synthetic Time-Lapse Sequences of Cell Populations in Fluorescence Microscopy.

    Svoboda, David; Ulman, Vladimir

    2017-01-01

    The proper analysis of biological microscopy images is an important and complex task. Therefore, it requires verification of all steps involved in the process, including image segmentation and tracking algorithms. It is generally better to verify algorithms with computer-generated ground truth datasets, which, compared to manually annotated data, nowadays have reached high quality and can be produced in large quantities even for 3D time-lapse image sequences. Here, we propose a novel framework, called MitoGen, which is capable of generating ground truth datasets with fully 3D time-lapse sequences of synthetic fluorescence-stained cell populations. MitoGen shows biologically justified cell motility, shape and texture changes as well as cell divisions. Standard fluorescence microscopy phenomena such as photobleaching, blur with real point spread function (PSF), and several types of noise, are simulated to obtain realistic images. The MitoGen framework is scalable in both space and time. MitoGen generates visually plausible data that shows good agreement with real data in terms of image descriptors and mean square displacement (MSD) trajectory analysis. Additionally, it is also shown in this paper that four publicly available segmentation and tracking algorithms exhibit similar performance on both real and MitoGen-generated data. The implementation of MitoGen is freely available.

  7. Resveratrol inhibits PDGF receptor mitogenic signaling in mesangial cells: role of PTP1B

    Venkatesan, Balachandar; Ghosh-Choudhury, Nandini; Das, Falguni; Mahimainathan, Lenin; Kamat, Amrita; Kasinath, Balakuntalam S.; Abboud, Hanna E.; Choudhury, Goutam Ghosh

    2008-01-01

    Mesangioproliferative glomerulonephritis is associated with overactive PDGF receptor signal transduction. We show that the phytoalexin resveratrol dose dependently inhibits PDGF-induced DNA synthesis in mesangial cells with an IC50 of 10 μM without inducing apoptosis. Remarkably, the increased SIRT1 deacetylase activity induced by resveratrol was not necessary for this inhibitory effect. Resveratrol significantly blocked PDGF-stimulated c-Src and Akt kinase activation, resulting in reduced cyclin D1 expression and attenuated pRb phosphorylation and cyclin-dependent kinase-2 (CDK2) activity. Furthermore, resveratrol inhibited PDGFR phosphorylation at the PI 3 kinase and Grb-2 binding sites tyrosine-751 and tyrosine-716, respectively. This deficiency in PDGFR phosphorylation resulted in significant inhibition of PI 3 kinase and Erk1/2 MAPK activity. Interestingly, resveratrol increased the activity of protein tyrosine phosphatase PTP1B, which dephosphorylates PDGF-stimulated phosphorylation at tyrosine-751 and tyrosine-716 on PDGFR with concomitant reduction in Akt and Erk1/2 kinase activity. PTP1B significantly inhibited PDGF-induced DNA synthesis without inducing apoptosis. These results for the first time provide evidence that the stilbene resveratrol targets PTP1B to inhibit PDGFR mitogenic signaling.—Venkatesan, B., Ghosh-Choudhury, N., Das, F., Mahimainathan, L., Kamat, A., Kasinath, B. S., Abboud, H. E., Choudhury, G. G. Resveratrol inhibits PDGF receptor mitogenic signaling in mesangial cells: role of PTP1B. PMID:18567737

  8. Rachycentron canadum (cobia) lectin promoted mitogenic response in mice BALB/c splenocytes.

    Coriolano, M C; de Melo, C M L; Santos, A J G; Pereira, V R A; Coelho, L C B B

    2012-12-01

    The mitogenic lectins are invaluable tools to study the biochemical changes associated with lymphocyte activation and proliferation of various immune cells. Rachycentron canadum lectin (RcaL) was detected and purified from serum of cobia fish. The aim of this study was to evaluate the proliferative response and cytokine production in splenocytes of mice in vitro stimulated with RcaL lectin; Canavalia ensiformis lectin (Con A) was used as positive control. A high proliferation index was induced by RcaL in relation to control cells. Furthermore, RcaL induced higher IL-2 and IL-6 production in relation to control. The cell viability was 90% in splenocytes treated with RcaL lectin, but RcaL promoted significant late apoptosis after 24 and 48 h in relation to control. RcaL induced proliferative responses suggesting that this lectin can be used as a mitogenic agent in immunostimulatory assays. © 2012 The Authors. Scandinavian Journal of Immunology © 2012 Blackwell Publishing Ltd.

  9. Comparative Molecular Dynamics Simulations of Mitogen-Activated Protein Kinase-Activated Protein Kinase 5

    Inger Lindin

    2014-03-01

    Full Text Available The mitogen-activated protein kinase-activated protein kinase MK5 is a substrate of the mitogen-activated protein kinases p38, ERK3 and ERK4. Cell culture and animal studies have demonstrated that MK5 is involved in tumour suppression and promotion, embryogenesis, anxiety, cell motility and cell cycle regulation. In the present study, homology models of MK5 were used for molecular dynamics (MD simulations of: (1 MK5 alone; (2 MK5 in complex with an inhibitor; and (3 MK5 in complex with the interaction partner p38α. The calculations showed that the inhibitor occupied the active site and disrupted the intramolecular network of amino acids. However, intramolecular interactions consistent with an inactive protein kinase fold were not formed. MD with p38α showed that not only the p38 docking region, but also amino acids in the activation segment, αH helix, P-loop, regulatory phosphorylation region and the C-terminal of MK5 may be involved in forming a very stable MK5-p38α complex, and that p38α binding decreases the residual fluctuation of the MK5 model. Electrostatic Potential Surface (EPS calculations of MK5 and p38α showed that electrostatic interactions are important for recognition and binding.

  10. Three mitogen-activated protein kinases required for cell wall integrity contribute greatly to biocontrol potential of a fungal entomopathogen.

    Ying Chen

    Full Text Available Bck1, Mkk1 and Slt2 are three mitogen-activated protein (MAP kinases constituting cell wall integrity (CWI pathway that may control multi-stress responses via crosstalk with high-osmolarity glycerol (HOG pathway in budding yeast. In this study, Bck1, Mkk1 and Slt2 orthologues in Beauveria bassiana were confirmed as the three-module cascade essential for CWI because cell wall impairment occurred in the hyphae and conidia of Δbck1, Δmkk1 and Δslt2 examined in multiple experiments. Strikingly, all the deletion mutants became more sensitive to hyperosmotic NaCl and sorbitol with the Western blot of Hog1 phosphorylation being weakened in Δbck1 and absent in Δmkk1 and Δslt2. Apart from crossing responses to cell wall perturbation and high osmolarity, three deletion mutants exhibited faster growth and conidiation on nutrition-rich medium, much less virulence to Galleria mellonella larvae, and higher sensitivity to nutritional, fungicidal, thermal and UV-B irradiative stresses, accompanied with less accumulation of intracellular mannitol and trehalose. Moreover, Δmkk1 and Δslt2 were equally more sensitive to all the stresses of different types except wet-heat stress than wild type and more or less different from Δbck1 in sensitivity to most of the stresses despite their null responses to two oxidants. All the changes in three deletion mutants were restored by each targeted gene complementation. Taken together, the CWI-required Bck1, Mkk1 and Slt2 are all positive, but differential, regulators of multi-stress tolerance and virulence perhaps due to interplay with the HOG pathway essential for osmoregulation, thereby contributing greatly to the biocontrol potential of the fungal entomopathogen.

  11. The mitogenic activities of bean proteins determined by assay of the incorporation of sup(3)H - thymidine by human lymphocytes

    Derbyshire, E.; Carvalho, M.T.V.; Vitti, D.M.S.; Costa, C.P. da

    1988-01-01

    The proteins in a saline extract from cotyledons of the bean cultivar Goiano precoce included a protein with electrophoretic mobility equal to that of a commercial preparation of bean mitogen. The crude extract stimulated the incorporation of sup(3)H-tymidine by cultures of human lymphocytes at concentrations of extracted protein from 30 mu g - 300 mu g/culture, and the existence of an optimal concentration in the vicinity of 175 mu g/culture was indicated by the data. The range of active concentrations and the optimal concentration of the heterogeneous extract were 12-15 times greater than the corresponding values obtained when the commercial mitogen was employed. Microscopic examinations showed the presence of blast cells and mitotic figures only in cultures which included seed extract or commercial mitogen. (author)

  12. The potent, indirect adenosine monophosphate-activated protein kinase activator R419 attenuates mitogen-activated protein kinase signaling, inhibits nociceptor excitability, and reduces pain hypersensitivity in mice

    Galo L. Mejia

    2016-07-01

    Full Text Available Abstract. There is a great need for new therapeutics for the treatment of pain. A possible avenue to development of such therapeutics is to interfere with signaling pathways engaged in peripheral nociceptors that cause these neurons to become hyperexcitable. There is strong evidence that mitogen-activated protein kinases and phosphoinositide 3-kinase (PI3K/mechanistic target of rapamycin signaling pathways are key modulators of nociceptor excitability in vitro and in vivo. Activation of adenosine monophosphate-activated protein kinase (AMPK can inhibit signaling in both of these pathways, and AMPK activators have been shown to inhibit nociceptor excitability and pain hypersensitivity in rodents. R419 is one of, if not the most potent AMPK activator described to date. We tested whether R419 activates AMPK in dorsal root ganglion (DRG neurons and if this leads to decreased pain hypersensitivity in mice. We find that R419 activates AMPK in DRG neurons resulting in decreased mitogen-activated protein kinase signaling, decreased nascent protein synthesis, and enhanced P body formation. R419 attenuates nerve growth factor (NGF-induced changes in excitability in DRG neurons and blocks NGF-induced mechanical pain amplification in vivo. Moreover, locally applied R419 attenuates pain hypersensitivity in a model of postsurgical pain and blocks the development of hyperalgesic priming in response to both NGF and incision. We conclude that R419 is a promising lead candidate compound for the development of potent and specific AMPK activation to inhibit pain hypersensitivity as a result of injury.

  13. Mitogen-activated protein kinase 1 from disk abalone (Haliotis discus discus): Roles in early development and immunity-related transcriptional responses.

    Perera, N C N; Godahewa, G I; Lee, Jehee

    2016-12-01

    Mitogen-activated protein kinase (MAPK) is involved in the regulation of cellular events by mediating signal transduction pathways. MAPK1 is a member of the extracellular-signal regulated kinases (ERKs), playing roles in cell proliferation, differentiation, and development. This is mainly in response to growth factors, mitogens, and many environmental stresses. In the current study, we have characterized the structural features of a homolog of MAPK1 from disk abalone (AbMAPK1). Further, we have unraveled its expressional kinetics against different experimental pathogenic infections or related chemical stimulants. AbMAPK1 harbors a 5' untranslated region (UTR) of 23 bps, a coding sequence of 1104 bps, and a 3' UTR of 448 bp. The putative peptide comprises a predicted molecular mass of 42.2 kDa, with a theoretical pI of 6.28. Based on the in silico analysis, AbMAPK1 possesses two N-glycosylation sites, one S_TK catalytic domain, and a conserved His-Arg-Asp domain (HRD). In addition, a conservative glycine rich ATP-phosphate-binding loop and a threonine-x-tyrosine motif (TEY) important for the autophosphorylation were also identified in the protein. Homology assessment of AbMAPK1 showed several conserved regions, and ark clam (Aplysia californica) showed the highest sequence identity (87.9%). The phylogenetic analysis supported close evolutionary kinship with molluscan orthologs. Constitutive expression of AbMAPK1 was observed in six different tissues of disk abalone, with the highest expression in the digestive tract, followed by the gills and hemocytes. Highest AbMAPK1 mRNA expression level was detected at the trochophore developmental stage, suggesting its role in abalone cell differentiation and proliferation. Significant modulation of AbMAPK1 expression under pathogenic stress suggested its putative involvement in the immune defense mechanism. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Electrical stimulation with periodic alternating intervals stimulates neuronal cells to produce neurotrophins and cytokines through activation of mitogen-activated protein kinase pathways.

    Yamamoto, Kenta; Yamamoto, Toshiro; Honjo, Kenichi; Ichioka, Hiroaki; Oseko, Fumishige; Kishida, Tsunao; Mazda, Osam; Kanamura, Narisato

    2015-12-01

    Peripheral neuropathy is a representative complication of dental surgery. Electrical therapy, based on electrical stimulation with periodic alternating intervals (ES-PAI), may promote nerve regeneration after peripheral nerve injury in a non-invasive manner, potentially providing an effective therapy for neuropathy. This study aimed to analyze the molecular mechanisms underlying the nerve recovery stimulated by ES-PAI. In brief, ES-PAI was applied to a neuronal cell line, Neuro2A, at various intensities using the pulse generator apparatus, FREUDE. Cell viability, neurotrophin mRNA expression, and cytokine production were examined using a tetrazolium-based assay, real-time RT-PCR, and ELISA, respectively. Mitogen-activated protein kinase (MAPK) signaling was assessed using flow cytometry. It was found that ES-PAI increased the viability of cells and elevated expression of nerve growth factor (NGF) and neurotrophin-3 (NT-3); ESPAI also augmented vascular endothelial growth factor (VEGF) and platelet-derived growth factor (PDGF) expression, which was restored by addition of p38 inhibitors. Phosphorylation of p38 and extracellular signal-regulated kinase 1/2 (ERK-1/2) was augmented by ES-PAI. Hence, ES-PAI may ameliorate peripheral neuropathy by promoting neuronal cell proliferation and production of neurogenic factors by activating p38 and ERK-1/2 pathways. © 2015 Eur J Oral Sci.

  15. The mitogen-activated protein kinase (MAPK pathway: role in immune evasion by trypanosomatids

    Mercedes Carolina Soares-Silva

    2016-02-01

    Full Text Available Leishmania spp and Trypanosoma cruzi are the causative agents of leishmaniasis and Chagas' disease, respectively, two neglected tropical diseases that affect about 25 million people worldwide. These parasites belong to the family Trypanosomatidae and are both obligate intracellular parasites that manipulate host signaling pathways to establish the infection, and also subvert the host innate immune system. Mitogen-activated protein kinases (MAPKs are serine and threonine protein kinases, highly conserved in eukaryotes, and are involved in signal transduction pathways that are related to modulation of physiological and pathophysiological cell responses. This mini-review highlights the current knowledge about the mechanisms that Leishmania spp and T. cruzi have evolved to target host MAPK signaling pathway, highjack immune response, and in this manner, promote parasite maintenance in the host.

  16. Functional Roles of p38 Mitogen-Activated Protein Kinase in Macrophage-Mediated Inflammatory Responses

    Yanyan Yang

    2014-01-01

    Full Text Available Inflammation is a natural host defensive process that is largely regulated by macrophages during the innate immune response. Mitogen-activated protein kinases (MAPKs are proline-directed serine and threonine protein kinases that regulate many physiological and pathophysiological cell responses. p38 MAPKs are key MAPKs involved in the production of inflammatory mediators, including tumor necrosis factor-α (TNF-α and cyclooxygenase-2 (COX-2. p38 MAPK signaling plays an essential role in regulating cellular processes, especially inflammation. In this paper, we summarize the characteristics of p38 signaling in macrophage-mediated inflammation. In addition, we discuss the potential of using inhibitors targeting p38 expression in macrophages to treat inflammatory diseases.

  17. Angiotensin II regulation of neuromodulation: downstream signaling mechanism from activation of mitogen-activated protein kinase.

    Lu, D; Yang, H; Raizada, M K

    1996-12-01

    Angiotensin II (Ang II) stimulates expression of tyrosine hydroxylase and norepinephrine transporter genes in brain neurons; however, the signal-transduction mechanism is not clearly defined. This study was conducted to determine the involvement of the mitogen-activated protein (MAP) kinase signaling pathway in Ang II stimulation of these genes. MAP kinase was localized in the perinuclear region of the neuronal soma. Ang II caused activation of MAP kinase and its subsequent translocation from the cytoplasmic to nuclear compartment, both effects being mediated by AT1 receptor subtype. Ang II also stimulated SRE- and AP1-binding activities and fos gene expression and its translocation in a MAP kinase-dependent process. These observations are the first demonstration of a downstream signaling pathway involving MAP kinase in Ang II-mediated neuromodulation in noradrenergic neurons.

  18. A single point mutation changes the crystallization behavior of Mycoplasma arthritidis-derived mitogen

    Guo, Yi; Li, Zhong; Van Vranken, Sandra J. [Wadsworth Center, New York State Department of Health, Empire State Plaza, PO Box 509, Albany, New York 12201-0509 (United States); Li, Hongmin, E-mail: lih@wadsworth.org [Wadsworth Center, New York State Department of Health, Empire State Plaza, PO Box 509, Albany, New York 12201-0509 (United States); Department of Biomedical Sciences, School of Public Health, University at Albany, State University of New York, Empire State Plaza, PO Box 509, Albany, New York 12201-0509 (United States)

    2006-03-01

    The mutagenesis, crystallization and preliminary crystallographic analysis of M. arthritidis-derived mitogen is described. Mycoplasma arthritidis-derived mitogen (MAM) functions as a conventional superantigen (SAg). Although recombinant MAM has been crystallized by the hanging-drop vapour-diffusion method, the crystals diffracted poorly to only 5.0 Å resolution, with large unit-cell parameters a = 163.8, b = 93.0, c = 210.9 Å, β = 93.7° in the monoclinic space group P2{sub 1}. Unit-cell content analysis revealed that as many as 24 molecules could be present in the asymmetric unit. Systematic alanine mutagenesis was applied in order to search for mutants that give crystals of better quality. Two mutants, L50A and K201A, were crystallized under the same conditions as wild-type MAM (MAM{sub wt}). Crystals of the L50A mutant are isomorphous with those of MAM{sub wt}, while a new crystal form was obtained for the K201 mutant, belonging to the cubic space group P4{sub 1}32 with unit-cell parameters a = b = c = 181.9 Å. Diffraction data were collected to 3.6 and 2.8 Å resolution from crystals of the MAM L50A and K201A mutants, respectively. Molecular-replacement calculations suggest the presence of two molecules in the asymmetric unit for the MAM K201A mutant crystal, resulting in a V{sub M} of 5.0 Å Da{sup −1} and a solvent content of 75%. An interpretable electron-density map for the MAM K201A mutant crystal was produced using the molecular-replacement method.

  19. Pentachlorophenol-Induced Cytotoxic, Mitogenic, and Endocrine-Disrupting Activities in Channel Catfish, Ictalurus punctatus

    Paul B. Tchounwou

    2004-09-01

    Full Text Available Pentachlorophenol (PCP is an organochlorine compound that has been widely used as a biocide in several industrial, agricultural, and domestic applications. Although it has been shown to induce systemic toxicity and carcinogenesis in several experimental studies, the literature is scarce regarding its toxic mechanisms of action at the cellular and molecular levels. Recent investigations in our laboratory have shown that PCP induces cytotoxicity and transcriptionally activates stress genes in human liver carcinoma (HepG2 cells [1]. In this research, we hypothesize that environmental exposure to PCP may trigger cytotoxic, mitogenic, and endocrine-disrupting activities in aquatic organisms including fish. To test this hypothesis, we carried out in vitro cultures of male channel catfish hepatocytes, and performed the fluorescein diacetate assay (FDA to assess for cell viability, and the Western Blot analysis to assess for vitellogenin expression following exposure to PCP. Data obtained from FDA experiments indicated a strong dose-response relationship with respect to PCP cytotoxicity. Upon 48 hrs of exposure, the chemical dose required to cause 50% reduction in cell viability (LD50 was computed to be 1,987.0 + 9.6 μg PCP/mL. The NOAEL and LOAEL were 62.5 + 10.3 μg PCP/mL and 125.0+15.2 μg PCP/mL, respectively. At lower levels of exposure, PCP was found to be mitogenic, showing a strong dose- and time-dependent response with regard to cell proliferation. Western Blot analysis demonstrated the potential of PCP to cause endocrine-disrupting activity, as evidenced by the up regulation of the 125-kDa vitellogenin protein the hepatocytes of male channel catfish.

  20. Time-dependent enhancement of lymphocyte activation by mitogens after exposure to isolation or water scheduling.

    Jessop, J J; Gale, K; Bayer, B M

    1988-01-01

    The effects of isolation and water scheduling on mitogen induced lymphocyte proliferation were investigated. Isolated rats were animals which had been raised in group-housed conditions and then transferred to individual cages with ad lib access to water for a 1 or 2 week period. Water scheduled rats were maintained in group housing (5 rats per cage) with ad lib access to food but with access to water for a single 30 minute session each day. Responses of these groups were compared to those of animals which had been continuously group-housed with ad lib access to food and water. No differences in lymphocyte responses to phytohemagglutinin (PHA) were found 1 week after exposure to isolation. However, after 2 weeks, splenic and blood T lymphocytes from isolated animals demonstrated an increased proliferative response to suboptimum and maximum concentrations of PHA. Splenic B lymphocyte responses to lipopolysaccharide (LPS) from isolated animals were also increased by 2- to 3-fold compared to group-housed controls. Two weeks of exposure of animals to daily water scheduling similarly increased the splenic lymphocyte proliferation. This increased responsiveness to PHA was not accompanied by a significant change in the sensitivity of the lymphocytes to PHA, in the total number of white blood cells, or the proportion of splenic T or T helper lymphocytes. Our results show that the increase in lymphocyte proliferation is time-dependent, requires greater than 1 week of exposure to isolation and is due to factors other than changes in sensitivity to mitogen or T lymphocyte number.

  1. Mitogen-Activated Protein Kinase Phosphatase-2 Deletion Impairs Synaptic Plasticity and Hippocampal-Dependent Memory.

    Abdul Rahman, Nor Zaihana; Greenwood, Sam M; Brett, Ros R; Tossell, Kyoko; Ungless, Mark A; Plevin, Robin; Bushell, Trevor J

    2016-02-24

    Mitogen-activated protein kinases (MAPKs) regulate brain function and their dysfunction is implicated in a number of brain disorders, including Alzheimer's disease. Thus, there is great interest in understanding the signaling systems that control MAPK function. One family of proteins that contribute to this process, the mitogen-activated protein kinase phosphatases (MKPs), directly inactivate MAPKs through dephosphorylation. Recent studies have identified novel functions of MKPs in development, the immune system, and cancer. However, a significant gap in our knowledge remains in relation to their role in brain functioning. Here, using transgenic mice where the Dusp4 gene encoding MKP-2 has been knocked out (MKP-2(-/-) mice), we show that long-term potentiation is impaired in MKP-2(-/-) mice compared with MKP-2(+/+) controls whereas neuronal excitability, evoked synaptic transmission, and paired-pulse facilitation remain unaltered. Furthermore, spontaneous EPSC (sEPSC) frequency was increased in acute slices and primary hippocampal cultures prepared from MKP-2(-/-) mice with no effect on EPSC amplitude observed. An increase in synapse number was evident in primary hippocampal cultures, which may account for the increase in sEPSC frequency. In addition, no change in ERK activity was detected in both brain tissue and primary hippocampal cultures, suggesting that the effects of MKP-2 deletion were MAPK independent. Consistent with these alterations in hippocampal function, MKP-2(-/-) mice show deficits in spatial reference and working memory when investigated using the Morris water maze. These data show that MKP-2 plays a role in regulating hippocampal function and that this effect may be independent of MAPK signaling. Copyright © 2016 Abdul Rahman et al.

  2. In vitro, inhibition of mitogen-activated protein kinase pathways protects against bupivacaine- and ropivacaine-induced neurotoxicity

    Lirk, Philipp; Haller, Ingrid; Colvin, Hans Peter; Lang, Leopold; Tomaselli, Bettina; Klimaschewski, Lars; Gerner, Peter

    2008-01-01

    Animal models show us that specific activation of the p38 mitogen-activated protein kinase (MAPK) may be a pivotal step in lidocaine neurotoxicity, but this has not been investigated in the case of two very widely used local anesthetics, bupivacaine and ropivacaine. We investigated the hypotheses

  3. The Mitogen-Activated Protein Kinase p38 alpha Regulates Tubular Damage in Murine Anti-Glomerular Basement Membrane Nephritis

    Mueller, Ralf; Daniel, Christoph; Hugo, Christian; Amann, Kerstin; Mielenz, Dirk; Endlich, Karlhans; Braun, Tobias; van der Veen, Betty; Heeringa, Peter; Schett, Georg; Zwerina, Jochen

    2013-01-01

    p38 mitogen-activated protein kinase (MAPK) is thought to play a central role in acute and chronic inflammatory responses. Whether p38MAPK plays a pathogenic role in crescentic GN (GN) and which of its four isoforms is preferentially involved in kidney inflammation is not definitely known. We thus

  4. Mitogen response of B cells, but not T cells, is impaired in adult vitamin A-deficient rats

    van Bennekum, A. M.; Wong Yen Kong, L. R.; Gijbels, M. J.; Tielen, F. J.; Roholl, P. J.; Brouwer, A.; Hendriks, H. F.

    1991-01-01

    The effect of vitamin A deficiency on the mitogen response of splenic B and T lymphocytes was determined in adult vitamin A-deficient rats. Female weanling Brown Norway/Billingham-Rijswijk (BN/BiRij) and Sprague-Dawley rats were fed a semipurified, essentially vitamin A-free diet, which resulted in

  5. Autoradiographic research on cell proliferation of prenatal rat lung cells and their influence using the mitogen Kallikrein

    Bock-Lamberlin, P.R.

    1980-01-01

    In this work autoradiographic experiments were carried out on the kinetics of proliferation of four cell populations of the prenatal rat lung with the help of the determination of the 3 H-thymidine marker indices, with the following results: 1. The four studied cell populations exhibited variable proliferation rates on the twentieth or twenty-first day of development. 2. The strongest affect of the exogenously applied mitogen Kallikrein was demonstrated on the vessel wall cells, the next strongest on the bronchial epithelial cells, then the cartilage cells and finally the alveolar wall cells. 3. The mitogenic effect is dependent on dose. Higher doses significantly increased the 3 H-thymidine marker indices of the four cell populations tested in this work. 4. When the exposure time of the Kallikrein was extended by one hour this lead partially to stronger mitogenic effects than by the shorter exposure times at the same and higher dose levels of mitogen. 5. The 3 H-thymidine marker indices are dependent on the exposure time. 6. With increasing litter size, the 3 H indices as a rule decrease. (orig./MG) [de

  6. Normal mitogen-induced suppression of the interleukin-6 (IL-6) response and its deficiency in systemic lupus erythematosus

    Warrington, R.J.; Rutherford, W.J.

    1990-01-01

    A low-frequency suppressor-cell population in normal peripheral blood inhibits the B-cell CESS response to IL-6, following pokeweed mitogen stimulation. The suppression of IL-6 responsiveness is radiation sensitive, directed against CESS targets and not mediated by inhibition of IL-6 production, and associated with nonspecific cytotoxic activity against CESS targets. The generation of these cytolytic cells is also radiation sensitive. A correlation was found between PWM-induced cytotoxicity against CESS and the suppression of IL-6-dependent IgG production. But cytotoxicity toward CESS targets is not responsible for this suppression because IL-2 induces equivalent or greater nonspecific cytotoxicity against CESS in the total absence of suppression of CESS-derived IgG production and suppression is also induced by mitogen-activated PBL separated from CESS targets by a cell-impermeable membrane. This suppression was not mediated by TNF alpha/beta or IFN-gamma. In systemic lupus erythematosus, suppression of IL-6-dependent IgG production is impaired in patients with active disease (29.2 +/- 13.7%) compared to patients with inactive disease (70 +/- 19.5%) or normal controls (82.8 +/- 9.2%). There is also a defect in mitogen-induced nonspecific cytotoxicity in active SLE (specific lysis 15.1 +/- 3.5%, compared to 34 +/- 4% in normals). Pokeweed mitogen-activated PBL can therefore normally induce suppression of B-cell IL-6 responses and this response is deficient in lupus

  7. The cis decoy against the estrogen response element suppresses breast cancer cells via target disrupting c-fos not mitogen-activated protein kinase activity.

    Wang, Li Hua; Yang, Xiao Yi; Zhang, Xiaohu; Mihalic, Kelly; Xiao, Weihua; Farrar, William L

    2003-05-01

    Breast cancer, the most common malignancy in women, has been demonstrated to be associated with the steroid hormone estrogen and its receptor (ER), a ligand-activated transcription factor. Therefore, we developed a phosphorothiolate cis-element decoy against the estrogen response element (ERE decoy) to target disruption of ER DNA binding and transcriptional activity. Here, we showed that the ERE decoy potently ablated the 17beta-estrogen-inducible cell proliferation and induced apoptosis of human breast carcinoma cells by functionally affecting expression of c-fos gene and AP-1 luciferase gene reporter activity. Specificity of the decoy was demonstrated by its ability to directly block ER binding to a cis-element probe and transactivation. Moreover, the decoy failed to inhibit ER-mediated mitogen-activated protein kinase signaling pathways and cell growth of ER-negative breast cancer cells. Taken together, these data suggest that estrogen-mediated cell growth of breast cancer cells can be preferentially restricted via targeted disruption of ER at the level of DNA binding by a novel and specific decoy strategy applied to steroid nuclear receptors.

  8. Growth hormone-releasing factor stimulates proliferation of somatotrophs in vitro

    Billestrup, Nils; Swanson, L W; Vale, W

    1986-01-01

    The mitogenic effect of the hypothalamic peptides growth hormone-releasing factor (GRF) and somatostatin on cultured growth hormone (GH)-producing cells (somatotrophs) was studied. Using autoradiographic detection of [3H]thymidine uptake and immunocytochemical identification of GH-producing cells...

  9. p38 mitogen-activated protein kinase plays a key role in regulating MAPKAPK2 expression

    Sudo, Tatsuhiko; Kawai, Kayoko; Matsuzaki, Hiroshi; Osada, Hiroyuki

    2005-01-01

    One of three major families of the mitogen-activated kinases (MAPK), p38 as well as JNK, has been shown to transduce extracellular stress stimuli into cellular responses by phospho-relay cascades. Among p38 families, p38α is a widely characterized isoform and the biological phenomena are explained by its kinase activity regulating functions of its downstream substrates. However, its specific contributions to each phenomenon are yet not fully elucidated. For better understanding of the role of MAPKs, especially p38α, we utilized newly established mouse fibroblast cell lines originated from a p38α null mouse, namely, a parental cell line without p38α gene locus, knockout of p38α (KOP), Zeosin-resistant (ZKOP), revertant of p38α (RKOP), and Exip revertant (EKOP). EKOP is smaller in size but grows faster than the others. Although comparable amounts of ERK and JNK are expressed in each cell line, ERK is highly phosphorylated in EKOP even in normal culture conditions. Serum stimulation after serum starvation led to ERK phosphorylation in RKOP and ZKOP, but not in EKOP as much. On the contrary, relative phosphorylation level of JNK to total JNK in response to UV was low in RKOP. And its phosphorylation as well as total JNK is slightly lower in EKOP. RKOP is less sensitive to UV irradiation as judged by the survival rate. Stress response upon UV or sorbitol stimuli, leading to mitogen activate protein kinase activated kinase 2 (MAPKAPK2) phosphorylation, was only observed in RKOP. Further experiments reveal that MAPKAPK2 expression is largely suppressed in ZKOP and EKOP. Its expression was recovered by re-introduction of p38α. The loss of MAPKAPK2 expression accompanied by the defect of p38α is confirmed in an embryonic extract prepared from p38α null mice. These data demonstrate that p38 signal pathway is regulated not only by phosphorylation but also by modulation of the expression of its component. Together, we have established cell lines that can be used in

  10. Expression of MMPs is dependent on the activity of mitogen-activated protein kinase in chondrosarcoma.

    Yao, Min; Wang, Xiaomei; Zhao, Yufeng; Wang, Xiaomeng; Gao, Feng

    2017-02-01

    Matrix metalloproteinases (MMPs) and tissue inhibitors of matrix metalloproteinases (TIMPs) serve an important role in chondrosarcoma. The present study investigated whether the expression of MMPs was dependent on the activity of mitogen-activated protein kinase (MAPK) in chondrosarcoma. Surgical pathological specimens were collected to detect MMP-1, MMP-13, TIMP-1, type II collagen and phosphorylated MAPK levels in normal cartilage, enchondroma and chondrosarcoma tissues. The expression of MMP‑1, MMP‑13, TIMP‑1 and type II collagen was investigated utilizing MAPK inhibitors in chondrosarcoma cells. It was noted that the expression levels of MMP‑1, MMP‑13 and TIMP‑1 were increased in chondrosarcoma with the activity of MAPK. After chondrosarcoma cells were pretreated with MAPK inhibitors, the levels of MMP‑1, MMP‑13 and TIMP‑1 were inhibited. Furthermore, MMP‑1 and MMP‑13 are essential in regulating the degradation of type II collagen and decomposing cartilage matrix major. The high expression levels of MMP‑1 and MMP‑13 in chondrosarcoma expedite the invasion by chondrosarcoma cells and their expression can be depressed by MAPK inhibitors.

  11. Regulation of WRKY46 transcription factor function by mitogen-activated protein kinases in Arabidopsis thaliana.

    Arsheed Hussain Sheikh

    2016-02-01

    Full Text Available AbstractMitogen-activated protein kinase (MAPK cascades are central signalling pathways activated in plants after sensing internal developmental and external stress cues. Knowledge about the downstream substrate proteins of MAPKs is still limited in plants. We screened Arabidopsis WRKY transcription factors as potential targets downstream of MAPKs, and concentrated on characterizing WRKY46 as a substrate of the MAPK, MPK3. Mass spectrometry revealed in vitro phosphorylation of WRKY46 at amino acid position S168 by MPK3. However, mutagenesis studies showed that a second phosphosite, S250, can also be phosphorylated. Elicitation with pathogen-associated molecular patterns (PAMPs, such as the bacterial flagellin-derived flg22 peptide led to in vivo destabilization of WRKY46 in Arabidopsis protoplasts. Mutation of either phosphorylation site reduced the PAMP-induced degradation of WRKY46. Furthermore, the protein for the double phosphosite mutant is expressed at higher levels compared to wild-type proteins or single phosphosite mutants. In line with its nuclear localization and predicted function as a transcriptional activator, overexpression of WRKY46 in protoplasts raised basal plant defence as reflected by the increase in promoter activity of the PAMP-responsive gene, NHL10, in a MAPK-dependent manner. Thus, MAPK-mediated regulation of WRKY46 is a mechanism to control plant defence.

  12. Lymphocyte proliferative responses to mitogens in rats having an ancestry of a perinatal iodine-131 insult

    Stevens, R.H.; Cheng, H.F.

    1987-01-01

    The possible existence of a genealogical memory consisting of altered lymphocyte proliferative responses to a perinatal iodine-131 insult has been investigated in two generations of inbred Fischer F344 rat offspring. The studies which involved exposure to the radioiodine during late pregnancy with concentrations ranging from 1.85 MBq (50 μCi) to 7.4 MBq (200 μCi) revealed that only the peripheral blood T lymphocytes of the first generation male animals were significantly affected. These animals were found to possess T lymphocytes which exhibited increased proliferative responses expressed toward the mitogens concanavalin A and phytohemagglutin; however, no significant changes were noticeable in their B cell population following exposure to lipopolysaccharide. Neither the first generation females nor the male and female offspring of the second generation developed through sibling interbreeding seemed to be affected, this was unlike the cellular, humoral, and natural immunity which had previously been observed to be changed in both the second and third generation animals. These observations suggest that the effects of the radiation insult upon immunocompetency as measured by lymphocyte proliferation do not appear to be inherited

  13. The mitogenic response of cryopreserved human lymphocytes in a microculture system.

    Steel, C M; Ennis, M; Levin, A G; Wasunna, A

    1977-01-01

    Fresh blood lymphocytes from nine health donors have been compared with samples from the same donors, recovered after period of 2 to 21 months storage in liquid nitrogen, for the capacity to respond to a range of mitogens in vitro. A microculture assay was used, requireing aliquots of only 25,000 cells. The mean levels of 14C-thymidine uptake for fresh and frozen samples were closely comparable when the cells had been stimulated by PHA, Pokeweed or mitomycin-C-treated allogeneic lymphoblastoid cells. Lymphocytes from six East African donors, frozen by a very simple technique, were recovered after 3 or more years storage in liquid nitrogen. Five of the samples were in good condition as judged by cell viability and the capacity to form spontaneous 'E' rosettes with sheep erythrocytes. These five samples also responded extremely well to PHA, PWM and mitomycin-C-treated allogeneic lymphoblastoid cells using the microculture assay. This study extends the range of applications of cell banks in which small aliquots of blood lymphocytes are stored in liquid nitrogen for periods of several years.

  14. T-dependence of human B lymphocyte proliferative response to mitogens.

    Brochier, J; Samarut, C; Gueho, J P; Revillard, J P

    1976-01-01

    Human peripheral blood and tonsil lymphocytes were fractionated on anti-Ig-coated Sephadex columns or by centrifugation after rosetting with native sheep erythrocytes. Both methods allowed the recovery of B and T-enriched populations the purity of which was checked by fluorescein-labelled anti-Ig serum, E and EAC rosette formation, and heterologous antisera specific for B or T lymphocytes. The proliferative response of T cells to PHA, Con A, PWM, and ALS was not found different from that of unfractionated cells, whereas no response of the B cells could be observed to these mitogens providing that no contaminating T cells were present. Addition of T lymphocytes to these unresponsive B cells allowed them to respond to phytomitogens, but not to ALS. X-irradiated T cells could, to some extent, replace the diving T lymphocytes; no T-replacing factor could be found in cell-free supernatants from T cells, whether or not they had been activated by mitrogens. This model of B-T cooperation appears useful for studying the differentiation and maturation of human B lymphocytes.

  15. The atypical mitogen-activated protein kinase ERK3 is essential for establishment of epithelial architecture.

    Takahashi, Chika; Miyatake, Koichi; Kusakabe, Morioh; Nishida, Eisuke

    2018-06-01

    Epithelia contribute to physical barriers that protect internal tissues from the external environment and also support organ structure. Accordingly, establishment and maintenance of epithelial architecture are essential for both embryonic development and adult physiology. Here, using gene knockout and knockdown techniques along with gene profiling, we show that extracellular signal-regulated kinase 3 (ERK3), a poorly characterized atypical mitogen-activated protein kinase (MAPK), regulates the epithelial architecture in vertebrates. We found that in Xenopus embryonic epidermal epithelia, ERK3 knockdown impairs adherens and tight-junction protein distribution, as well as tight-junction barrier function, resulting in epidermal breakdown. Moreover, in human epithelial breast cancer cells, inhibition of ERK3 expression induced thickened epithelia with aberrant adherens and tight junctions. Results from microarray analyses suggested that transcription factor AP-2α (TFAP2A), a transcriptional regulator important for epithelial gene expression, is involved in ERK3-dependent changes in gene expression. Of note, TFAP2A knockdown phenocopied ERK3 knockdown in both Xenopus embryos and human cells, and ERK3 was required for full activation of TFAP2A-dependent transcription. Our findings reveal that ERK3 regulates epithelial architecture, possibly together with TFAP2A. © 2018 by The American Society for Biochemistry and Molecular Biology, Inc.

  16. Mitogen-activated protein kinases interacting kinases are autoinhibited by a reprogrammed activation segment.

    Jauch, Ralf; Cho, Min-Kyu; Jäkel, Stefan; Netter, Catharina; Schreiter, Kay; Aicher, Babette; Zweckstetter, Markus; Jäckle, Herbert; Wahl, Markus C

    2006-09-06

    Autoinhibition is a recurring mode of protein kinase regulation and can be based on diverse molecular mechanisms. Here, we show by crystal structure analysis, nuclear magnetic resonance (NMR)-based nucleotide affinity studies and rational mutagenesis that nonphosphorylated mitogen-activated protein (MAP) kinases interacting kinase (Mnk) 1 is autoinhibited by conversion of the activation segment into an autoinhibitory module. In a Mnk1 crystal structure, the activation segment is repositioned via a Mnk-specific sequence insertion at the N-terminal lobe with the following consequences: (i) the peptide substrate binding site is deconstructed, (ii) the interlobal cleft is narrowed, (iii) an essential Lys-Glu pair is disrupted and (iv) the magnesium-binding loop is locked into an ATP-competitive conformation. Consistently, deletion of the Mnk-specific insertion or removal of a conserved phenylalanine side chain, which induces a blockade of the ATP pocket, increase the ATP affinity of Mnk1. Structural rearrangements required for the activation of Mnks are apparent from the cocrystal structure of a Mnk2 D228G -staurosporine complex and can be modeled on the basis of crystal packing interactions. Our data suggest a novel regulatory mechanism specific for the Mnk subfamily.

  17. Mesenchymal stem cells inhibit lymphocyte proliferation by mitogens and alloantigens by different mechanisms

    Rasmusson, Ida; Ringden, Olle; Sundberg, Berit; Le Blanc, Katarina

    2005-01-01

    Human mesenchymal stem cells (MSCs) have immuno-modulatory properties. They inhibit T-cell proliferation to mitogens and alloantigens in vitro and prolong skin graft survival in vivo. We found that MSCs inhibited the proliferation of peripheral blood lymphocytes (PBLs) to phorbol myristate acetate (PMA), suggesting that MSCs exert an inhibitory effect downstream of the receptor level. We analyzed cytokine profiles of PBLs co-cultured with MSCs. MSCs increased interleukin (IL)-2 and soluble IL-2 receptor in mixed lymphocyte cultures (MLCs), while IL-2 and IL-2R decreased in phytohemagglutinin (PHA)-stimulated PBL cultures. MSCs inhibited IL-2 induced proliferation, without absorbing IL-2. IL-10 levels increased in MLCs co-cultured with 10% MSCs, while the levels were not affected in PHA cultures. In MLCs inhibited by MSCs, antibodies against IL-10 further suppressed proliferation but had no effect in PHA cultures. Addition of indomethacin, an inhibitor of prostaglandin-synthesis, restored part of the inhibition by MSCs in PHA cultures. However, indomethacin did not affect MSC-induced inhibition in MLCs. To conclude, our data indicate that MSC-induced suppression is a complex mechanism affecting IL-2 and IL-10 signaling and may function differently, depending on T-cell stimuli. Prostaglandins are important in the inhibition by MSCs when the T cells were activated by PHA, but not alloantigens

  18. Inability of newborns' or pregnant women's monocytes to suppress pokeweed mitogen-induced responses

    Durandy, A.; Fischer, A.; Griscelli, C.

    1982-01-01

    Although an excess of human adult blood adherent cells inhibits the pokeweed mitogen- (PWM) induced normal adult lymphocyte proliferation and B cell maturation into immunoglobulin-containing cells (ICC), adherent cells collected from newborn infants or pregnant women at time of delivery were unable to exert a similar suppressor activity. After activation by Concanavalin A (Con A), newborns' and pregnant women's adherent cells acquired a suppressor activity comparable to that of control adult adherent cells. The adherent suppressor cell was shown to be radioresistant (3000 rad), indicating its probable monocytic orgin. Both monocyte-suppressor activities (MSA) observed in adulthood (spontaneously) and in the neonatal period (after activation) were dependent on prostaglandin E 2 (PGE 2 ) secretion, because they were abolished by indomethacin or a specific anti-PGE 2 anti-serum. Expression of MSA appeared to be under a negative regulation exerted by naturally occurring T suppressor lymphocytes present in the blood of newborns or pregnant women, because incubation of adult monocytes or Con A-activated newborn monocytes with newborns' or pregnant women's T lymphocytes resulted in a dramatic decrease of their MSA. These results strongly suggest that the lack of MSA in the neonatal period and in late pregnancy is a consequence of activation of T suppressor lymphocytes

  19. An inhibition of p38 mitogen activated protein kinase delays the platelet storage lesion.

    Andrey Skripchenko

    Full Text Available BACKGROUND AND OBJECTIVES: Platelets during storage undergo diverse alterations collectively known as the platelet storage lesion, including metabolic, morphological, functional and structural changes. Some changes correlate with activation of p38 mitogen activated protein kinase (p38 MAPK. Another MAPK, extracellular signal-related kinase (ERK, is involved in PLT activation. The aim of this study was to compare the properties of platelets stored in plasma in the presence or absence of p38 and ERK MAPK inhibitors. MATERIALS AND METHODS: A single Trima apheresis platelet unit (n = 12 was aliquoted into five CLX storage bags. Two aliquots were continuously agitated with or without MAPK inhibitors. Two aliquots were subjected to 48 hours of interruption of agitation with or without MAPK inhibitors. One aliquot contained the same amount of solvent vehicle used to deliver the inhibitor. Platelets were stored at 20-24°C for 7 days and sampled on Days 1, 4, and 7 for 18 in vitro parameters. RESULTS: Inhibition of p38 MAPK by VX-702 leads to better maintenance of all platelet in vitro storage parameters including platelet mitochondrial function. Accelerated by interruption of agitation, the platelet storage lesion of units stored with VX-702 was diminished to that of platelets stored with continuous agitation. Inhibition of ERK MAPK did not ameliorate decrements in any in vitro platelet properties. CONCLUSION: Signaling through p38 MAPK, but not ERK, is associated with platelet deterioration during storage.

  20. Mercuric ions inhibit mitogen-activated protein kinase dephosphorylation by inducing reactive oxygen species

    Haase, Hajo; Engelhardt, Gabriela; Hebel, Silke; Rink, Lothar

    2011-01-01

    Mercury intoxication profoundly affects the immune system, in particular, signal transduction of immune cells. However, the mechanism of the interaction of mercury with cellular signaling pathways, such as mitogen activated protein kinases (MAPK), remains elusive. Therefore, the objective of this study is to investigate three potential ways in which Hg 2+ ions could inhibit MAPK dephosphorylation in the human T-cell line Jurkat: (1) by direct binding to phosphatases; (2) by releasing cellular zinc (Zn 2+ ); and (3) by inducing reactive oxygen species (ROS). Hg 2+ causes production of ROS, measured by dihydrorhodamine 123, and triggers ROS-mediated Zn 2+ release, detected with FluoZin-3. Yet, phosphatase-inhibition is not mediated by binding of Zn 2+ or Hg 2+ . Rather, phosphatases are inactivated by at least two forms of thiol oxidation; initial inhibition is reversible with reducing agents such as Tris(2-carboxyethyl)phosphine. Prolonged inhibition leads to non-reversible phosphatase oxidation, presumably oxidizing the cysteine thiol to sulfinic- or sulfonic acid. Notably, phosphatases are a particularly sensitive target for Hg 2+ -induced oxidation, because phosphatase activity is inhibited at concentrations of Hg 2+ that have only minor impact on over all thiol oxidation. This phosphatase inhibition results in augmented, ROS-dependent MAPK phosphorylation. MAPK are important regulators of T-cell function, and MAPK-activation by inhibition of phosphatases seems to be one of the molecular mechanisms by which mercury affects the immune system.

  1. Review: Mitogen-Activated Protein kinases in nutritional signaling in Arabidopsis

    Chardin, Camille

    2017-04-14

    Mitogen-Activated Protein Kinase (MAPK) cascades are functional modules widespread among eukaryotic organisms. In plants, these modules are encoded by large multigenic families and are involved in many biological processes ranging from stress responses to cellular differentiation and organ development. Furthermore, MAPK pathways are involved in the perception of environmental and physiological modifications. Interestingly, some MAPKs play a role in several signaling networks and could have an integrative function for the response of plants to their environment. In this review, we describe the classification of MAPKs and highlight some of their biochemical actions. We performed an in silico analysis of MAPK gene expression in response to nutrients supporting their involvement in nutritional signaling. While several MAPKs have been identified as players in sugar, nitrogen, phosphate, iron and potassium-related signaling pathways, their biochemical functions are yet mainly unknown. The integration of these regulatory cascades in the current understanding of nutrient signaling is discussed and potential new avenues for approaches toward plants with higher nutrient use efficiencies are evoked.

  2. Review: Mitogen-Activated Protein kinases in nutritional signaling in Arabidopsis

    Chardin, Camille; Schenk, Sebastian T.; Hirt, Heribert; Colcombet, Jean; Krapp, Anne

    2017-01-01

    Mitogen-Activated Protein Kinase (MAPK) cascades are functional modules widespread among eukaryotic organisms. In plants, these modules are encoded by large multigenic families and are involved in many biological processes ranging from stress responses to cellular differentiation and organ development. Furthermore, MAPK pathways are involved in the perception of environmental and physiological modifications. Interestingly, some MAPKs play a role in several signaling networks and could have an integrative function for the response of plants to their environment. In this review, we describe the classification of MAPKs and highlight some of their biochemical actions. We performed an in silico analysis of MAPK gene expression in response to nutrients supporting their involvement in nutritional signaling. While several MAPKs have been identified as players in sugar, nitrogen, phosphate, iron and potassium-related signaling pathways, their biochemical functions are yet mainly unknown. The integration of these regulatory cascades in the current understanding of nutrient signaling is discussed and potential new avenues for approaches toward plants with higher nutrient use efficiencies are evoked.

  3. The relationship between lymphocytes activated by pokeweed mitogen and by lipopolysaccharides and their radiosensitivity

    Su Liaoyuan; Liu Fenju; Liu Keliang; Xu Changshao; Xu Yingdong; Geng Yongzhi

    1992-07-01

    Human whole blood was incubated in vitro. Lymphocytes were activated by poke-weed mitogen (PWM) and by Lipopolysaccharides (LPS). The relationship between the two kinds of lymphocytes was investigated using radioactive compound incorporation. The study showed that PWM-activated lymphocytes were able to promote the stimulating effect of LPS on B lymphocytes. The stimulating effect of PWM-activated lymphocytes was obviously decreased after they were irradiated with 10 Gy gamma rays. When PWM-activated lymphocytes and LPS-activated lymphocytes were incubated together after one of the cell populations had been exposed 10 Gy 60 Co gamma rays, the incorporation of [ 3 H] TdR was much decreased and the synergistic function disappeared, especially when the PWM-activated lymphocytes were irradiated. In cells from patients treated with 60 Co gamma rays for carcinoma of nasopharynx, the incorporation in LPS-activated lymphocytes approached normal levels while that in PWM-activated lymphocytes was reduced significantly and the stimulating effect of PWM-activated lymphocytes on LPS-activated lymphocytes was also markedly reduced. These demonstrate that PWM-activated lymphocytes have a similar function to T-helper cells and seem to be more radiosensitive than LPS-activated lymphocytes

  4. Sustained mitogen-activated protein kinase activation reprograms defense metabolism and phosphoprotein profile in Arabidopsis thaliana.

    Ines eLassowskat

    2014-10-01

    Full Text Available Mitogen-activated protein kinases (MAPKs target a variety of protein substrates to regulate cellular signaling processes in eukaryotes. In plants, the number of identified MAPK substrates that control plant defense responses is still limited. Here, we generated transgenic Arabidopsis thaliana plants with an inducible system to simulate in vivo activation of two stress-activated MAPKs, MPK3 and MPK6. Metabolome analysis revealed that this artificial MPK3/6 activation (without any exposure to pathogens or other stresses is sufficient to drive the production of major defense-related metabolites, including various camalexin, indole glucosinolate and agmatine derivatives. An accompanying (phosphoproteome analysis led to detection of hundreds of potential phosphoproteins downstream of MPK3/6 activation. Besides known MAPK substrates, many candidates on this list possess typical MAPK-targeted phosphosites and in many cases, the corresponding phosphopeptides were detected by mass spectrometry. Notably, several of these putative phosphoproteins have been reported to be associated with the biosynthesis of antimicrobial defense substances (e.g. WRKY transcription factors and proteins encoded by the genes from the PEN pathway required for penetration resistance to filamentous pathogens. Thus, this work provides an inventory of candidate phosphoproteins, including putative direct MAPK substrates, for future analysis of MAPK-mediated defense control. (Proteomics data are available with the identifier PXD001252 via ProteomeXchange, http://proteomecentral.proteomexchange.org.

  5. Tumors initiated by constitutive Cdk2 activation exhibit transforming growth factor beta resistance and acquire paracrine mitogenic stimulation during progression

    Corsino, P.; Davis, B.; Law, M.

    2007-01-01

    ) promoter results in mammary gland hyperplasia and fibrosis, and mammary tumors. Cell lines isolated from MMTV-cyclin D1-Cdk2 (MMTV-D1K2) tumors exhibit Rb and p130 hyperphosphorylation and up-regulation of the protein products of E2F-dependent genes. These results suggest that cyclin D1/Cdk2 complexes may...... sites. Together, these results suggest that deregulation of the Cdk/Rb/E2F axis reprograms mammary epithelial cells to initiate a paracrine loop with tumor-associated fibroblasts involving TGF beta and HGF, resulting in desmoplasia. The MMTV-DIK2 mice should provide a useful model system...

  6. Tumors initiated by constitutive Cdk2 activation exhibit transforming growth factor beta resistance and acquire paracrine mitogenic stimulation during progression

    Corsino, P.; Davis, B.; Law, M.

    2007-01-01

    Cyclin D1/cyclin-dependent kinase 2 (Cdk2) complexes are present at high frequency in human breast cancer cell lines, but the significance of this observation is unknown. This report shows that expression of a cyclin D1-Cdk2 fusion protein under the control of the mouse mammary tumor virus (MMITV...

  7. Cytotoxicity and mitogenicity assays with real-time and label-free monitoring of human granulosa cells with an impedance-based signal processing technology intergrating micro-electronics and cell biology.

    Oktem, Ozgur; Bildik, Gamze; Senbabaoglu, Filiz; Lack, Nathan A; Akin, Nazli; Yakar, Feridun; Urman, Defne; Guzel, Yilmaz; Balaban, Basak; Iwase, Akira; Urman, Bulent

    2016-04-01

    A recently developed technology (xCelligence) integrating micro-electronics and cell biology allows real-time, uninterrupted and quantitative analysis of cell proliferation, viability and cytotoxicity by measuring the electrical impedance of the cell population in the wells without using any labeling agent. In this study we investigated if this system is a suitable model to analyze the effects of mitogenic (FSH) and cytotoxic (chemotherapy) agents with different toxicity profiles on human granulosa cells in comparison to conventional methods of assessing cell viability, DNA damage, apoptosis and steroidogenesis. The system generated the real-time growth curves of the cells, and determined their doubling times, mean cell indices and generated dose-response curves after exposure to cytotoxic and mitogenic stimuli. It accurately predicted the gonadotoxicity of the drugs and distinguished less toxic agents (5-FU and paclitaxel) from more toxic ones (cisplatin and cyclophosphamide). This platform can be a useful tool for specific end-point assays in reproductive toxicology. Copyright © 2015 Elsevier Inc. All rights reserved.

  8. Arabidopsis Raf-Like Mitogen-Activated Protein Kinase Kinase Kinase Gene Raf43 Is Required for Tolerance to Multiple Abiotic Stresses.

    Nasar Virk

    Full Text Available Mitogen-activated protein kinase (MAPK cascades are critical signaling modules that mediate the transduction of extracellular stimuli into intracellular response. A relatively large number of MAPKKKs have been identified in a variety of plant genomes but only a few of them have been studied for their biological function. In the present study, we identified an Arabidopsis Raf-like MAPKKK gene Raf43 and studied its function in biotic and abiotic stress response using a T-DNA insertion mutant raf43-1 and two Raf43-overexpressing lines Raf43-OE#1 and Raf43-OE#13. Expression of Raf43 was induced by multiple abiotic and biotic stresses including treatments with drought, mannitol and oxidative stress or defense signaling molecule salicylic acid and infection with necrotrophic fungal pathogen Botrytis cinerea. Seed germination and seedling root growth of raf43-1 were significantly inhibited on MS medium containing mannitol, NaCl, H2O2 or methyl viologen (MV while seed germination and seedling root growth of the Raf43-OE#1 and Raf43-OE#13 lines was similar to wild type Col-0 under the above stress conditions. Soil-grown raf43-1 plants exhibited reduced tolerance to MV, drought and salt stress. Abscisic acid inhibited significantly seed germination and seedling root growth of the raf43-1 line but had no effect on the two Raf43-overexpressing lines. Expression of stress-responsive RD17 and DREB2A genes was significantly down-regulated in raf43-1 plants. However, the raf43-1 and Raf43-overexpressing plants showed similar disease phenotype to the wild type plants after infection with B. cinerea or Pseudomonas syringae pv. tomato DC3000. Our results demonstrate that Raf43, encoding for a Raf-like MAPKKK, is required for tolerance to multiple abiotic stresses in Arabidopsis.

  9. Mitogen activated protein kinase 6 and MAP kinase phosphatase 1 are involved in the response of Arabidopsis roots to L-glutamate.

    López-Bucio, Jesús Salvador; Raya-González, Javier; Ravelo-Ortega, Gustavo; Ruiz-Herrera, León Francisco; Ramos-Vega, Maricela; León, Patricia; López-Bucio, José; Guevara-García, Ángel Arturo

    2018-03-01

    The function and components of L-glutamate signaling pathways in plants have just begun to be elucidated. Here, using a combination of genetic and biochemical strategies, we demonstrated that a MAPK module is involved in the control of root developmental responses to this amino acid. Root system architecture plays an essential role in plant adaptation to biotic and abiotic factors via adjusting signal transduction and gene expression. L-Glutamate (L-Glu), an amino acid with neurotransmitter functions in animals, inhibits root growth, but the underlying genetic mechanisms are poorly understood. Through a combination of genetic analysis, in-gel kinase assays, detailed cell elongation and division measurements and confocal analysis of expression of auxin, quiescent center and stem cell niche related genes, the critical roles of L-Glu in primary root growth acting through the mitogen-activated protein kinase 6 (MPK6) and the dual specificity serine-threonine-tyrosine phosphatase MKP1 could be revealed. In-gel phosphorylation assays revealed a rapid and dose-dependent induction of MPK6 and MPK3 activities in wild-type Arabidopsis seedlings in response to L-Glu. Mutations in MPK6 or MKP1 reduced or increased root cell division and elongation in response to L-Glu, possibly modulating auxin transport and/or response, but in a PLETHORA1 and 2 independent manner. Our data highlight MPK6 and MKP1 as components of an L-Glu pathway linking the auxin response, and cell division for primary root growth.

  10. Purification and characterization of a mucin specific mycelial lectin from Aspergillus gorakhpurensis: application for mitogenic and antimicrobial activity.

    Singh, Ram Sarup; Kaur, Hemant Preet; Singh, Jatinder

    2014-01-01

    Lectins are carbohydrate binding proteins or glycoproteins that bind reversibly to specific carbohydrates present on the apposing cells, which are responsible for their ability to agglutinate red blood cells, lymphocytes, fibroblasts, etc. Interest in lectins has been intensified due to their carbohydrate specificity as they can be valuable reagents for the investigation of cell surface sugars, purification and characterization of glycoproteins. The present study reports the purification, characterization and evaluation of mitogenic and antimicrobial potential of a mycelial lectin from Aspergillus gorakhpurensis. Affinity chromatography on mucin-sepharose column was carried out for purification of Aspergillus gorakhpurensis lectin. The lectin was characterized for physico-chemical parameters. Mitogenic potential of the lectin was evaluated against splenocytes of Swiss albino mice by MTT assay. Antimicrobial activity of the purified lectin has also been evaluated by disc diffusion assay. Single-step affinity purification resulted in 18.6-fold purification of the mycelial lectin. The molecular mass of the lectin was found to be 70 kDa and it was composed of two subunits of 34.8 kDa as determined by gel filtration chromatography, SDS-PAGE and MALDI-TOF analysis. pH optima of the lectin was found to be 6.5-9.5, while optimum temperature for lectin activity was 20-30 °C. Lectin was stable within a pH range of 7.0-10.5 and showed fair thermostability. EDTA did not affect lectin activity whereas it was found susceptible to the denaturants tested. MTT assay revealed strong mitogenic potential of A. gorakhpurensis lectin at a concentration upto 150 µg/mL. Antimicrobial activity assay showed its potent antibacterial activity against Bacillus cereus, Staphylococcous aureus and Escherichia coli and marginal antifungal activity against Saccharomyces cerevisiae. This is the first report on the mitogenic and antimicrobial potential of Aspergillus gorakhpurensis lectin. The

  11. Aspergillus nidulans Natural Product Biosynthesis Is Regulated by MpkB, a Putative Pheromone Response Mitogen-Activated Protein Kinase

    Atoui, A.; Bao, D.; Kaur, N.; Grayburn, W.S.; Calvo, A.M.

    2008-01-01

    The Aspergillus nidulans putative mitogen-activated protein kinase encoded by mpkB has a role in natural product biosynthesis. An mpkB mutant exhibited a decrease in sterigmatocystin gene expression and low mycotoxin levels. The mutation also affected the expression of genes involved in penicillin and terrequinone A synthesis. mpkB was necessary for normal expression of laeA, which has been found to regulate secondary metabolism gene clusters. (author)

  12. Toward a Comprehensive Phylogenetic Reconstruction of the Evolutionary History of Mitogen-Activated Protein Kinases in the Plant Kingdom

    Janitza, Philipp; Ullrich, Kristian Karsten; Quint, Marcel

    2012-01-01

    The mitogen-activated protein kinase (MAPK) pathway is a three-tier signaling cascade that transmits cellular information from the plasma membrane to the cytoplasm where it triggers downstream responses. The MAPKs represent the last step in this cascade and are activated when both tyrosine and threonine residues in a conserved TxY motif are phosphorylated by MAPK kinases, which in turn are themselves activated by phosphorylation by MAPK kinase kinases. To understand the molecular evolution of...

  13. Three Fusarium oxysporum mitogen-activated protein kinases (MAPKs) have distinct and complementary roles in stress adaptation and cross-kingdom pathogenicity.

    Segorbe, David; Di Pietro, Antonio; Pérez-Nadales, Elena; Turrà, David

    2017-09-01

    Mitogen-activated protein kinase (MAPK) cascades mediate cellular responses to environmental signals. Previous studies in the fungal pathogen Fusarium oxysporum have revealed a crucial role of Fmk1, the MAPK orthologous to Saccharomyces cerevisiae Fus3/Kss1, in vegetative hyphal fusion and plant infection. Here, we genetically dissected the individual and combined contributions of the three MAPKs Fmk1, Mpk1 and Hog1 in the regulation of development, stress response and virulence of F. oxysporum on plant and animal hosts. Mutants lacking Fmk1 or Mpk1 were affected in reactive oxygen species (ROS) homeostasis and impaired in hyphal fusion and aggregation. Loss of Mpk1 also led to increased sensitivity to cell wall and heat stress, which was exacerbated by simultaneous inactivation of Fmk1, suggesting that both MAPKs contribute to cellular adaptation to high temperature, a prerequisite for mammalian pathogens. Deletion of Hog1 caused increased sensitivity to hyperosmotic stress and resulted in partial rescue of the restricted colony growth phenotype of the mpk1Δ mutant. Infection assays on tomato plants and the invertebrate animal host Galleria mellonella revealed distinct and additive contributions of the different MAPKs to virulence. Our results indicate that positive and negative cross-talk between the three MAPK pathways regulates stress adaptation, development and virulence in the cross-kingdom pathogen F. oxysporum. © 2016 BSPP AND JOHN WILEY & SONS LTD.

  14. MaHog1, a Hog1-type mitogen-activated protein kinase gene, contributes to stress tolerance and virulence of the entomopathogenic fungus Metarhizium acridum.

    Jin, Kai; Ming, Yue; Xia, Yu Xian

    2012-12-01

    Fungal biocontrol agents have great potential in integrated pest management. However, poor efficacy and sensitivity to various adverse factors have hampered their wide application. In eukaryotic cells, Hog1 kinase plays a critical role in stress responses. In this study, MaHog1 (GenBank accession no. EFY85878), encoding a member of the Hog1/Sty1/p38 mitogen-activated protein kinase family in Metarhizium (Me.) acridum, was identified. Targeted gene disruption was used to analyse the role of MaHog1 in virulence and tolerance of adverse factors. Mutants with MaHog1 depletion showed increased sensitivity to high osmotic stress, high temperature and oxidative stress, and exhibited remarkable resistance to cell wall-disturbing agents. These results suggest that Hog1 kinase has a conserved function in regulating multistress responses among fungi, and that MaHog1 might influence cell wall biogenesis in Me. acridum. Bioassays conducted with topical inoculation and intrahaemocoel injection revealed that MaHog1 is required for both penetration and postpenetration development of Me. acridum. MaHog1 disruption resulted in a significant reduction in virulence, likely due to the combination of a decrease in conidial germination, a reduction in appressorium formation and a decline in growth rate in insect haemolymph, which might be caused by impairing fungal tolerance of various stresses during infection.

  15. Repeated pulses of serotonin required for long-term facilitation activate mitogen-activated protein kinase in sensory neurons of Aplysia

    Michael, Dan; Martin, Kelsey C.; Seger, Rony; Ning, Ming-Ming; Baston, Rene; Kandel, Eric R.

    1998-01-01

    Long-term facilitation of the connections between the sensory and motor neurons of the gill-withdrawal reflex in Aplysia requires five repeated pulses of serotonin (5-HT). The repeated pulses of 5-HT initiate a cascade of gene activation that leads ultimately to the growth of new synaptic connections. Several genes in this process have been identified, including the transcriptional regulators apCREB-1, apCREB-2, apC/EBP, and the cell adhesion molecule apCAM, which is thought to be involved in the formation of new synaptic connections. Here we report that the transcriptional regulators apCREB-2 and apC/EBP, as well as a peptide derived from the cytoplasmic domain of apCAM, are phosphorylated in vitro by Aplysia mitogen-activated protein kinase (apMAPK). We have cloned the cDNA encoding apMAPK and show that apMAPK activity is increased in sensory neurons treated with repeated pulses of 5-HT and by the cAMP pathway. These results suggest that apMAPK may participate with cAMP-dependent protein kinase during long-term facilitation in sensory cells by modifying some of the key elements involved in the consolidation of short- to long-lasting changes in synaptic strength. PMID:9465108

  16. Loss of Mitogen-Activated Protein Kinase Kinase Kinase 4 (MAP3K4) Reveals a Requirement for MAPK Signalling in Mouse Sex Determination

    Bogani, Debora; Siggers, Pam; Brixey, Rachel; Warr, Nick; Beddow, Sarah; Edwards, Jessica; Williams, Debbie; Wilhelm, Dagmar; Koopman, Peter; Flavell, Richard A.; Chi, Hongbo; Ostrer, Harry; Wells, Sara; Cheeseman, Michael; Greenfield, Andy

    2009-01-01

    Sex determination in mammals is controlled by the presence or absence of the Y-linked gene SRY. In the developing male (XY) gonad, sex-determining region of the Y (SRY) protein acts to up-regulate expression of the related gene, SOX9, a transcriptional regulator that in turn initiates a downstream pathway of testis development, whilst also suppressing ovary development. Despite the requirement for a number of transcription factors and secreted signalling molecules in sex determination, intracellular signalling components functioning in this process have not been defined. Here we report a role for the phylogenetically ancient mitogen-activated protein kinase (MAPK) signalling pathway in mouse sex determination. Using a forward genetic screen, we identified the recessive boygirl (byg) mutation. On the C57BL/6J background, embryos homozygous for byg exhibit consistent XY gonadal sex reversal. The byg mutation is an A to T transversion causing a premature stop codon in the gene encoding MAP3K4 (also known as MEKK4), a mitogen-activated protein kinase kinase kinase. Analysis of XY byg/byg gonads at 11.5 d post coitum reveals a growth deficit and a failure to support mesonephric cell migration, both early cellular processes normally associated with testis development. Expression analysis of mutant XY gonads at the same stage also reveals a dramatic reduction in Sox9 and, crucially, Sry at the transcript and protein levels. Moreover, we describe experiments showing the presence of activated MKK4, a direct target of MAP3K4, and activated p38 in the coelomic region of the XY gonad at 11.5 d post coitum, establishing a link between MAPK signalling in proliferating gonadal somatic cells and regulation of Sry expression. Finally, we provide evidence that haploinsufficiency for Map3k4 accounts for T-associated sex reversal (Tas). These data demonstrate that MAP3K4-dependent signalling events are required for normal expression of Sry during testis development, and create a novel

  17. Loss of mitogen-activated protein kinase kinase kinase 4 (MAP3K4 reveals a requirement for MAPK signalling in mouse sex determination.

    Debora Bogani

    2009-09-01

    Full Text Available Sex determination in mammals is controlled by the presence or absence of the Y-linked gene SRY. In the developing male (XY gonad, sex-determining region of the Y (SRY protein acts to up-regulate expression of the related gene, SOX9, a transcriptional regulator that in turn initiates a downstream pathway of testis development, whilst also suppressing ovary development. Despite the requirement for a number of transcription factors and secreted signalling molecules in sex determination, intracellular signalling components functioning in this process have not been defined. Here we report a role for the phylogenetically ancient mitogen-activated protein kinase (MAPK signalling pathway in mouse sex determination. Using a forward genetic screen, we identified the recessive boygirl (byg mutation. On the C57BL/6J background, embryos homozygous for byg exhibit consistent XY gonadal sex reversal. The byg mutation is an A to T transversion causing a premature stop codon in the gene encoding MAP3K4 (also known as MEKK4, a mitogen-activated protein kinase kinase kinase. Analysis of XY byg/byg gonads at 11.5 d post coitum reveals a growth deficit and a failure to support mesonephric cell migration, both early cellular processes normally associated with testis development. Expression analysis of mutant XY gonads at the same stage also reveals a dramatic reduction in Sox9 and, crucially, Sry at the transcript and protein levels. Moreover, we describe experiments showing the presence of activated MKK4, a direct target of MAP3K4, and activated p38 in the coelomic region of the XY gonad at 11.5 d post coitum, establishing a link between MAPK signalling in proliferating gonadal somatic cells and regulation of Sry expression. Finally, we provide evidence that haploinsufficiency for Map3k4 accounts for T-associated sex reversal (Tas. These data demonstrate that MAP3K4-dependent signalling events are required for normal expression of Sry during testis development, and

  18. Pre-ERCP infusion of semapimod, a mitogen-activated protein kinases inhibitor, lowers post-ERCP hyperamylasemia but not pancreatitis incidence

    van Westerloo, David J.; Rauws, Erik A.; Hommes, Daan; de Vos, Alex F.; van der Poll, Tom; Powers, Barbara L.; Fockens, Paul; Dijkgraaf, Marcel G. W.; Bruno, Marco J.

    2008-01-01

    BACKGROUND: Acute pancreatitis and hyperamylasemia are frequent complications of an ERCP. Semapimod is a synthetic guanylhydrazone that inhibits the mitogen-activated protein kinase (MAPK) pathway, macrophage activation, and the production of several inflammatory cytokines. OBJECTIVE: This study

  19. Protein tyrosine kinase and mitogen-activated protein kinase signalling pathways contribute to differences in heterophil-mediated innate immune responsiveness between two lines of broilers

    Protein tyrosine phosphorylation mediates signal transduction of cellular processes, with protein tyrosine kinases (PTKs) regulating virtually all signaling events. The mitogen-activated protein kinase (MAPK) super-family consists of three conserved pathways that convert receptor activation into ce...

  20. Lectins of Erythrina poeppigiana and Erythrina steyermarkii (Leguminosae: characterization and mitogenic effect

    Silvia Quesada

    1998-12-01

    Full Text Available Erythrina species are widely distributed in Costa Rica and known popularly as "poró". In this study, two species were selected, Erythrina poeppigiana and Erythrina steyermarkii. Seed extracts were prepared in phosphate-buffered saline. The presence of lectins in the extracts was verified by hemagglutinating effect over suspensions of human erythrocytes. A selective hemagglutinating effect on erythrocytes of several mammal species, goat, horse and rabbit red cells was tested; only the latter were agglutinated by E. steyermarkii. The hemagglutinating effect of both lectins was inhibited with the following carbohydrates: D-galactose, N-acetyl galactosamine, D-lactose and D-raffinose. The lectin from E. steyermarkii was also inhibited with L-rhamnose. Both lectins were isolated with gel filtration and affinity chromatography using lactose as ligand. Fractions that proved positive were tested with the sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE. Gel filtration and SDS-PAGE showed that these lectins have an apparent molecular mass of 50kDa, and are formed by two subunits of approximately 25 kDa. E. poeppigiana had no mitogenic effect, but the extract of E. steyermarkii had a mitogenic effect on human mononuclear cells isolated from peripheral blood. The stability of the lectins was tested at different temperature and pH ranges (4 to 100 °C and at pH 2 to 12. Both were stable at a pH range from 2 to 10, and at temperatures from 40 to 70 °C.Las diferentes especies de Erythrina se encuentran ampliamente distribuidas en Costa Rica y se las conoce popularmente con el nombre de "poró". En el presente estudio, se seleccionaron dos especies: Erythrina poeppigiana y Erythrina steyermarkii. Se prepararon extractos de las semillas en solución tampón salina de fosfatos y se verificó la presencia de lectinas en ellos mediante la técnica de hemaglutinación, utilizando eritrocitos humanos. Se trató de demostrar un efecto selectivo

  1. Noise exposure immediately activates cochlear mitogen-activated protein kinase signaling

    Kumar N Alagramam

    2014-01-01

    Full Text Available Noise-induced hearing loss (NIHL is a major public health issue worldwide. Uncovering the early molecular events associated with NIHL would reveal mechanisms leading to the hearing loss. Our aim is to investigate the immediate molecular responses after different levels of noise exposure and identify the common and distinct pathways that mediate NIHL. Previous work showed mice exposed to 116 decibels sound pressure level (dB SPL broadband noise for 1 h had greater threshold shifts than the mice exposed to 110 dB SPL broadband noise, hence we used these two noise levels in this study. Groups of 4-8-week-old CBA/CaJ mice were exposed to no noise (control or to broadband noise for 1 h, followed by transcriptome analysis of total cochlear RNA isolated immediately after noise exposure. Previously identified and novel genes were found in all data sets. Following exposure to noise at 116 dB SPL, the earliest responses included up-regulation of 243 genes and down-regulation of 61 genes, while a similar exposure at 110 dB SPL up-regulated 155 genes and down-regulated 221 genes. Bioinformatics analysis indicated that mitogen-activated protein kinase (MAPK signaling was the major pathway in both levels of noise exposure. Nevertheless, both qualitative and quantitative differences were noticed in some MAPK signaling genes, after exposure to different noise levels. Cacna1b , Cacna1g , and Pla2g6 , related to calcium signaling were down-regulated after 110 dB SPL exposure, while the fold increase in the expression of Fos was relatively lower than what was observed after 116 dB SPL exposure. These subtle variations provide insight on the factors that may contribute to the differences in NIHL despite the activation of a common pathway.

  2. β-endorphin modulation of mitogen-stimulated calcium uptake by rat thymocytes

    Hemmick, L.M.; Bidlack, J.M.

    1987-01-01

    Lymphocytes stimulated by mitogens or antigens exhibit an enhanced calcium uptake early in the proliferation or activation response. Modulation of this calcium uptake results in alterations of proliferation and immunocompetence. β-endorphin and other opioids affect several parameters of lymphocyte competence. Limited data are available concerning the mechanism(s) of these effects. This study examines whether a possible opioid mechanism is the modification of the early calcium influx into stimulated lymphocytes. The time course of both concanavalin A (Con A) and phytohemagglutinin (PHA)-stimulated 45 Ca 2+ uptake into thymocytes was characterized to determine the optimal time for testing the effects of opioids. Β-Endorphin 1-31 significantly enhanced Con A-stimulated 45 Ca 2+ uptake into rat thymocytes. This peptide had no significant effect on PHA-simulated 45 Ca 2+ uptake or on basal thymocyte 45 Ca 2+ flux. The β/sub h/-endorphin stimulatory effect was titratable in the range of 0.1 nM to 10 μM. Naloxone did not reverse the enhancement. Met-enkephalinamide and other opioid agonists did not duplicate the stimulatory effect. Thus, the β/sub h/-endorphin 1-31 enhancement of Con A-stimulated 45 Ca 2+ uptake by rat thymocytes does not operate via classical opioid receptor mechanisms. β/sub h/-endorphin 1-31 appears to be acting on a subset of T cells that are responsive to Con A but not to PHA. 30 references, 4 figures, 1 table

  3. Detection of prosecretory mitogen lacritin in nonprimate tears primarily as a C-terminal-like fragment.

    Laurie, Diane E; Splan, Rebecca K; Green, Kari; Still, Katherine M; McKown, Robert L; Laurie, Gordon W

    2012-09-12

    Lacritin is a human tear glycoprotein that promotes basal tear protein secretion in cultured rat lacrimal acinar cells and proliferation of subconfluent human corneal epithelial cells. When topically added to rabbit eyes, lacritin promotes basal tearing. Despite these activities on several species, lacritin's presence in nonprimate tears or other tissues has not been explored. Here we probed for lacritin in normal horse tears. Sequences were collected from the Ensembl genomic alignment of human LACRT gene with high-quality draft horse genome (EquCab2.0) and analyzed. Normal horse tears were collected and assayed by Western blotting, ELISA, and mass spectrometry. Newly generated rabbit antibodies, respectively, against N- and C-terminal regions of human lacritin were employed. Identity was 75% and 45%, respectively, at nucleotide and protein levels. Structural features were conserved, including a C-terminal amphipathic α-helix. Anti-C-terminal antibodies strongly detected a ∼13 kDa band in horse tears that was validated by mass spectrometry. In human tears, the same antibody detected uncleaved lacritin (∼24 kDa) strongly and C-terminal fragments of ∼13 and ∼11 kDa weakly. Anti-N-terminal antibodies were slightly reactive with a ∼24 kDa horse antigen and showed no reaction with the anti-C-terminal-reactive ∼13 kDa species. Similar respective levels of horse C-terminal versus N-terminal immunoreactivity were apparent by ELISA. Lacritin is present in horse tears, largely as a C-terminal fragment homologous to the mitogenic and bactericidal region in human lacritin, suggesting potential benefit in corneal wound repair.

  4. Mitogen-Activated Protein Kinase Kinase 3 Regulates Seed Dormancy in Barley.

    Nakamura, Shingo; Pourkheirandish, Mohammad; Morishige, Hiromi; Kubo, Yuta; Nakamura, Masako; Ichimura, Kazuya; Seo, Shigemi; Kanamori, Hiroyuki; Wu, Jianzhong; Ando, Tsuyu; Hensel, Goetz; Sameri, Mohammad; Stein, Nils; Sato, Kazuhiro; Matsumoto, Takashi; Yano, Masahiro; Komatsuda, Takao

    2016-03-21

    Seed dormancy has fundamental importance in plant survival and crop production; however, the mechanisms regulating dormancy remain unclear [1-3]. Seed dormancy levels generally decrease during domestication to ensure that crops successfully germinate in the field. However, reduction of seed dormancy can cause devastating losses in cereals like wheat (Triticum aestivum L.) and barley (Hordeum vulgare L.) due to pre-harvest sprouting, the germination of mature seed (grain) on the mother plant when rain occurs before harvest. Understanding the mechanisms of dormancy can facilitate breeding of crop varieties with the appropriate levels of seed dormancy [4-8]. Barley is a model crop [9, 10] and has two major seed dormancy quantitative trait loci (QTLs), SD1 and SD2, on chromosome 5H [11-19]. We detected a QTL designated Qsd2-AK at SD2 as the single major determinant explaining the difference in seed dormancy between the dormant cultivar "Azumamugi" (Az) and the non-dormant cultivar "Kanto Nakate Gold" (KNG). Using map-based cloning, we identified the causal gene for Qsd2-AK as Mitogen-activated Protein Kinase Kinase 3 (MKK3). The dormant Az allele of MKK3 is recessive; the N260T substitution in this allele decreases MKK3 kinase activity and appears to be causal for Qsd2-AK. The N260T substitution occurred in the immediate ancestor allele of the dormant allele, and the established dormant allele became prevalent in barley cultivars grown in East Asia, where the rainy season and harvest season often overlap. Our findings show fine-tuning of seed dormancy during domestication and provide key information for improving pre-harvest sprouting tolerance in barley and wheat. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. beta. -endorphin modulation of mitogen-stimulated calcium uptake by rat thymocytes

    Hemmick, L.M.; Bidlack, J.M.

    1987-10-19

    Lymphocytes stimulated by mitogens or antigens exhibit an enhanced calcium uptake early in the proliferation or activation response. Modulation of this calcium uptake results in alterations of proliferation and immunocompetence. ..beta..-endorphin and other opioids affect several parameters of lymphocyte competence. Limited data are available concerning the mechanism(s) of these effects. This study examines whether a possible opioid mechanism is the modification of the early calcium influx into stimulated lymphocytes. The time course of both concanavalin A (Con A) and phytohemagglutinin (PHA)-stimulated /sup 45/Ca/sup 2 +/ uptake into thymocytes was characterized to determine the optimal time for testing the effects of opioids. BETA-Endorphin 1-31 significantly enhanced Con A-stimulated /sup 45/Ca/sup 2 +/ uptake into rat thymocytes. This peptide had no significant effect on PHA-simulated /sup 45/Ca/sup 2 +/ uptake or on basal thymocyte /sup 45/Ca/sup 2 +/ flux. The ..beta../sub h/-endorphin stimulatory effect was titratable in the range of 0.1 nM to 10 ..mu..M. Naloxone did not reverse the enhancement. Met-enkephalinamide and other opioid agonists did not duplicate the stimulatory effect. Thus, the ..beta../sub h/-endorphin 1-31 enhancement of Con A-stimulated /sup 45/Ca/sup 2 +/ uptake by rat thymocytes does not operate via classical opioid receptor mechanisms. ..beta../sub h/-endorphin 1-31 appears to be acting on a subset of T cells that are responsive to Con A but not to PHA. 30 references, 4 figures, 1 table.

  6. Mitogen activated protein kinases selectively regulate palytoxin-stimulated gene expression in mouse keratinocytes

    Zeliadt, Nicholette A.; Warmka, Janel K.; Wattenberg, Elizabeth V.

    2003-01-01

    We have been investigating how the novel skin tumor promoter palytoxin transmits signals through mitogen activated protein kinases (MAPKs). Palytoxin activates three major MAPKs, extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK), and p38, in a keratinocyte cell line derived from initiated mouse skin (308). We previously showed that palytoxin requires ERK to increase matrix metalloproteinase-13 (MMP-13) gene expression, an enzyme implicated in carcinogenesis. Diverse stimuli require JNK and p38 to increase MMP-13 gene expression, however. We therefore used the JNK and p38 inhibitors SP 600125 and SB 202190, respectively, to investigate the role of these MAPKs in palytoxin-induced MMP-13 gene expression. Surprisingly, palytoxin does not require JNK and p38 to increase MMP-13 gene expression. Accordingly, ERK activation, independent of palytoxin and in the absence of JNK and p38 activation, is sufficient to induce MMP-13 gene expression in 308 keratinocytes. Dexamethasone, a synthetic glucocorticoid that inhibits activator protein-1 (AP-1), blocked palytoxin-stimulated MMP-13 gene expression. Therefore, the AP-1 site present in the promoter of the MMP-13 gene appears to be functional and to play a key role in palytoxin-stimulated gene expression. Previous studies showed that palytoxin simulates an ERK-dependent selective increase in the c-Fos content of AP-1 complexes that bind to the promoter of the MMP-13 gene. JNK and p38 can also modulate c-Fos. Palytoxin does not require JNK or p38 to increase c-Fos binding, however. Altogether, these studies indicate that ERK plays a distinctly essential role in transmitting palytoxin-stimulated signals to specific nuclear targets in keratinocytes derived from initiated mouse skin

  7. Mitogen-stimulated phospholipid synthesis in normal and immune-deficient human B cells

    Chien, M.M.; Yokoyama, W.M.; Ashman, R.F.

    1986-01-01

    Eight patients with common variable panhypogammaglobulinemia were shown in the in vitro Ig biosynthesis assay to have defective B cell responses to pokeweed mitogen (PWM). Phospholipid synthesis was assessed in the B cell plus monocyte fraction (MB) and irradiated T cells (T*) of patients and paired normal controls. Cell populations were studied separately and in the four possible combinations (1:1), with and without PWM, to reveal the effect of cell interactions. At 16 to 20 hr the mean stimulation index (SI) +/- standard error for MB cells alone was 1.01 +/- 0.02 for eight patients and 0.99 +/- 0.02 for the paired normals; the T* cell SI was 1.25 +/- 0.04 for patients and 1.28 +/- 0.05 for normals. Combinations of normal MB cells with normal T* cells showed significantly higher SI when compared with the combinations of normal MB cells with patient T* cells (p less than 0.005). However, the combination of patient MB cells with patient T* cells and the combination of patient MB cells with normal T* cells were not significantly different in SI (0.05 less than p less than 0.1). Isolation of patient and normal B cells, T* cells, and monocytes after the choline pulse showed that patient B cells gave a higher SI with normal T* help than with patient T* help. Of greatest interest is the finding that patient B cells that were defective in PWM-stimulated Ig production nevertheless showed a phospholipid synthesis response to PWM in the normal range, suggesting that the maturation defect in these B cells occurs later than the phospholipid synthesis acceleration step, or on a different pathway

  8. Cyclic nucleotides and mitogen-activated protein kinases: regulation of simvastatin in platelet activation

    Hou Ssu-Yu

    2010-06-01

    Full Text Available Abstract Background 3-Hydroxy-3-methyl-glutaryl coenzyme A (HMG-CoA reductase inhibitors (statins have been widely used to reduce cardiovascular risk. These statins (i.e., simvastatin may exert other effects besides from their cholesterol-lowering actions, including inhibition of platelet activation. Platelet activation is relevant to a variety of coronary heart diseases. Although the inhibitory effect of simvastatin in platelet activation has been studied; the detailed signal transductions by which simvastatin inhibit platelet activation has not yet been completely resolved. Methods The aim of this study was to systematically examine the detailed mechanisms of simvastatin in preventing platelet activation. Platelet aggregation, flow cytometric analysis, immunoblotting, and electron spin resonance studies were used to assess the antiplatelet activity of simvastatin. Results Simvastatin (20-50 μM exhibited more-potent activity of inhibiting platelet aggregation stimulated by collagen than other agonists (i.e., thrombin. Simvastatin inhibited collagen-stimulated platelet activation accompanied by [Ca2+]i mobilization, thromboxane A2 (TxA2 formation, and phospholipase C (PLCγ2, protein kinase C (PKC, and mitogen-activated protein kinases (i.e., p38 MAPK, JNKs phosphorylation in washed platelets. Simvastatin obviously increased both cyclic AMP and cyclic GMP levels. Simvastatin markedly increased NO release, vasodilator-stimulated phosphoprotein (VASP phosphorylation, and endothelial nitric oxide synthase (eNOS expression. SQ22536, an inhibitor of adenylate cyclase, markedly reversed the simvastatin-mediated inhibitory effects on platelet aggregation, PLCγ2 and p38 MAPK phosphorylation, and simvastatin-mediated stimulatory effects on VASP and eNOS phosphorylation. Conclusion The most important findings of this study demonstrate for the first time that inhibitory effect of simvastatin in platelet activation may involve activation of the cyclic AMP

  9. Regulation of Schistosoma mansoni development and reproduction by the mitogen-activated protein kinase signaling pathway.

    Andrade, Luiza Freire de; Mourão, Marina de Moraes; Geraldo, Juliana Assis; Coelho, Fernanda Sales; Silva, Larissa Lopes; Neves, Renata Heisler; Volpini, Angela; Machado-Silva, José Roberto; Araujo, Neusa; Nacif-Pimenta, Rafael; Caffrey, Conor R; Oliveira, Guilherme

    2014-06-01

    Protein kinases are proven targets for drug development with an increasing number of eukaryotic Protein Kinase (ePK) inhibitors now approved as drugs. Mitogen-activated protein kinase (MAPK) family members connect cell-surface receptors to regulatory targets within cells and influence a number of tissue-specific biological activities such as cell proliferation, differentiation and survival. However, the contributions of members of the MAPK pathway to schistosome development and survival are unclear. We employed RNA interference (RNAi) to elucidate the functional roles of five S. mansoni genes (SmCaMK2, SmJNK, SmERK1, SmERK2 and SmRas) involved in MAPK signaling pathway. Mice were injected with post-infective larvae (schistosomula) subsequent to RNAi and the development of adult worms observed. The data demonstrate that SmJNK participates in parasite maturation and survival of the parasites, whereas SmERK are involved in egg production as infected mice had significantly lower egg burdens with female worms presenting underdeveloped ovaries. Furthermore, it was shown that the c-fos transcription factor was overexpressed in parasites submitted to RNAi of SmERK1, SmJNK and SmCaMK2 indicating its putative involvement in gene regulation in this parasite's MAPK signaling cascade. We conclude that MAPKs proteins play important roles in the parasite in vivo survival, being essential for normal development and successful survival and reproduction of the schistosome parasite. Moreover SmERK and SmJNK are potential targets for drug development.

  10. Effects of hepatocyte growth factor on glutathione synthesis, growth, and apoptosis is cell density-dependent

    Yang Heping; Magilnick, Nathaniel; Xia Meng; Lu, Shelly C.

    2008-01-01

    Hepatocyte growth factor (HGF) is a potent hepatocyte mitogen that exerts opposing effects depending on cell density. Glutathione (GSH) is the main non-protein thiol in mammalian cells that modulates growth and apoptosis. We previously showed that GSH level is inversely related to cell density of hepatocytes and is positively related to growth. Our current work examined whether HGF can modulate GSH synthesis in a cell density-dependent manner and how GSH in turn influence HGF's effects. We found HGF treatment of H4IIE cells increased cell GSH levels only under subconfluent density. The increase in cell GSH under low density was due to increased transcription of GSH synthetic enzymes. This correlated with increased protein levels and nuclear binding activities of c-Jun, c-Fos, p65, p50, Nrf1 and Nrf2 to the promoter region of these genes. HGF acts as a mitogen in H4IIE cells under low cell density and protects against tumor necrosis factor α (TNFα)-induced apoptosis by limiting JNK activation. However, HGF is pro-apoptotic under high cell density and exacerbates TNFα-induced apoptosis by potentiating JNK activation. The increase in cell GSH under low cell density allows HGF to exert its full mitogenic effect but is not necessary for its anti-apoptotic effect

  11. Upstream and Downstream Co-inhibition of Mitogen-Activated Protein Kinase and PI3K/Akt/mTOR Pathways in Pancreatic Ductal Adenocarcinoma

    Matthew H. Wong

    2016-07-01

    Full Text Available BACKGROUND: Extensive cross talk exists between PI3K/Akt/mTOR and mitogen-activated protein kinase (MAPK pathways, and both are upregulated in pancreatic ductal adenocarcinoma (PDAC. Our previous study suggested that epidermal growth factor receptor inhibitor erlotinib which acts upstream of these pathways acts synergistically with PI3K inhibitors in PDAC. Horizontal combined blockade upstream and downstream of these two pathways is therefore explored. METHODS: Erlotinib paired with PI3K inhibitor (BYL719 was tested against erlotinib plus dual PI3K/mTOR inhibitor BEZ-235, and MEK inhibitor (PD98059 plus BEZ235, on five primary PDAC cell lines and on two pairs of parent and erlotinib-resistant (ER cell lines. A range of in vitro assays including cell proliferation, Western blotting, migration, clonogenic, cell cycle, and apopotic assays was used to test for the efficacy of combined blockade. RESULTS: Dual downstream blockade of the MAPK and PAM pathways was more effective in attenuating downstream molecular signals. Synergy was demonstrated for erlotinib and BEZ235 and for PD-98059 and BEZ-235. This resulted in a trend of increased growth cell cycle arrest, apoptosis, cell proliferation, and colony and migration suppression. This combination showed more efficacy in cell lines with acquired resistance to erlotinib. CONCLUSIONS: The additional mTOR blockade provided by BEZ235 in combined blockade resulted in increased anticancer effect. The hypersensitivity of ER cell lines to additional mTOR blockade suggested PAM pathway oncogenic dependence via mTOR. Dual downstream combined blockade of MAPK and PAM pathways with MEK and PI3K/mTOR inhibitor appeared most effective and represents an attractive therapeutic strategy against pancreatic cancer and its associated drug resistance.

  12. Cancer Cell-derived Exosomes Induce Mitogen-activated Protein Kinase-dependent Monocyte Survival by Transport of Functional Receptor Tyrosine Kinases*

    Song, Xiao; Ding, Yanping; Liu, Gang; Yang, Xiao; Zhao, Ruifang; Zhang, Yinlong; Zhao, Xiao; Anderson, Gregory J.; Nie, Guangjun

    2016-01-01

    Tumor-associated macrophages (TAM) play pivotal roles in cancer initiation and progression. Monocytes, the precursors of TAMs, normally undergo spontaneous apoptosis within 2 days, but can subsist in the inflammatory tumor microenvironment for continuous survival and generation of sufficient TAMs. The mechanisms underlying tumor-driving monocyte survival remain obscure. Here we report that cancer cell-derived exosomes were crucial mediators for monocyte survival in the inflammatory niche. Analysis of the survival-promoting molecules in monocytes revealed that cancer cell-derived exosomes activated Ras and extracellular signal-regulated kinases in the mitogen-activated protein kinase (MAPK) pathway, resulting in the prevention of caspase cleavage. Phosphorylated receptor tyrosine kinases (RTKs), such as phosphorylated epidermal growth factor receptor (EGFR) and human epidermal growth factor receptor 2 (HER-2), were abundantly expressed in cancer cell-derived exosomes. Knock-out of EGFR or/and HER-2, or alternatively, inhibitors against their phosphorylation significantly disturbed the exosome-mediated activation of the MAPK pathway, inhibition of caspase cleavage, and increase in survival rate in monocytes. Moreover, the deprived survival-stimulating activity of exosomes due to null expression of EGFR and HER-2 could be restored by activation of another RTK, insulin receptor. Overall, our study uncovered a mechanism of tumor-associated monocyte survival and demonstrated that cancer cell-derived exosomes can stimulate the MAPK pathway in monocytes through transport of functional RTKs, leading to inactivation of apoptosis-related caspases. This work provides insights into the long sought question on monocyte survival prior to formation of plentiful TAMs in the tumor microenvironment. PMID:26895960

  13. Cancer Cell-derived Exosomes Induce Mitogen-activated Protein Kinase-dependent Monocyte Survival by Transport of Functional Receptor Tyrosine Kinases.

    Song, Xiao; Ding, Yanping; Liu, Gang; Yang, Xiao; Zhao, Ruifang; Zhang, Yinlong; Zhao, Xiao; Anderson, Gregory J; Nie, Guangjun

    2016-04-15

    Tumor-associated macrophages (TAM) play pivotal roles in cancer initiation and progression. Monocytes, the precursors of TAMs, normally undergo spontaneous apoptosis within 2 days, but can subsist in the inflammatory tumor microenvironment for continuous survival and generation of sufficient TAMs. The mechanisms underlying tumor-driving monocyte survival remain obscure. Here we report that cancer cell-derived exosomes were crucial mediators for monocyte survival in the inflammatory niche. Analysis of the survival-promoting molecules in monocytes revealed that cancer cell-derived exosomes activated Ras and extracellular signal-regulated kinases in the mitogen-activated protein kinase (MAPK) pathway, resulting in the prevention of caspase cleavage. Phosphorylated receptor tyrosine kinases (RTKs), such as phosphorylated epidermal growth factor receptor (EGFR) and human epidermal growth factor receptor 2 (HER-2), were abundantly expressed in cancer cell-derived exosomes. Knock-out of EGFR or/and HER-2, or alternatively, inhibitors against their phosphorylation significantly disturbed the exosome-mediated activation of the MAPK pathway, inhibition of caspase cleavage, and increase in survival rate in monocytes. Moreover, the deprived survival-stimulating activity of exosomes due to null expression of EGFR and HER-2 could be restored by activation of another RTK, insulin receptor. Overall, our study uncovered a mechanism of tumor-associated monocyte survival and demonstrated that cancer cell-derived exosomes can stimulate the MAPK pathway in monocytes through transport of functional RTKs, leading to inactivation of apoptosis-related caspases. This work provides insights into the long sought question on monocyte survival prior to formation of plentiful TAMs in the tumor microenvironment. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  14. p75 Neurotrophin Receptor Signaling Activates Sterol Regulatory Element-binding Protein-2 in Hepatocyte Cells via p38 Mitogen-activated Protein Kinase and Caspase-3.

    Pham, Dan Duc; Do, Hai Thi; Bruelle, Céline; Kukkonen, Jyrki P; Eriksson, Ove; Mogollón, Isabel; Korhonen, Laura T; Arumäe, Urmas; Lindholm, Dan

    2016-05-13

    Nerve growth factor (NGF) influences the survival and differentiation of a specific population of neurons during development, but its role in non-neuronal cells has been less studied. We observed here that NGF and its pro-form, pro-NGF, are elevated in fatty livers from leptin-deficient mice compared with controls, concomitant with an increase in low density lipoprotein receptors (LDLRs). Stimulation of mouse primary hepatocytes with NGF or pro-NGF increased LDLR expression through the p75 neurotrophin receptor (p75NTR). Studies using Huh7 human hepatocyte cells showed that the neurotrophins activate the sterol regulatory element-binding protein-2 (SREBP2) that regulates genes involved in lipid metabolism. The mechanisms for this were related to stimulation of p38 mitogen-activated protein kinase (p38 MAPK) and activation of caspase-3 and SREBP2 cleavage following NGF and pro-NGF stimulations. Cell fractionation experiments showed that caspase-3 activity was increased particularly in the membrane fraction that harbors SREBP2 and caspase-2. Experiments showed further that caspase-2 interacts with pro-caspase-3 and that p38 MAPK reduced this interaction and caused caspase-3 activation. Because of the increased caspase-3 activity, the cells did not undergo cell death following p75NTR stimulation, possibly due to concomitant activation of nuclear factor-κB (NF-κB) pathway by the neurotrophins. These results identify a novel signaling pathway triggered by ligand-activated p75NTR that via p38 MAPK and caspase-3 mediate the activation of SREBP2. This pathway may regulate LDLRs and lipid uptake particularly after injury or during tissue inflammation accompanied by an increased production of growth factors, including NGF and pro-NGF. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  15. The motogenic and mitogenic responses to HGF are amplified by the Shc adaptor protein

    Pelicci, G; Giordano, S; Zhen, Z

    1995-01-01

    The receptor of Hepatocyte Growth Factor-Scatter Factor (HGF) is a tyrosine kinase which regulates cell motility and growth. After ligand-induced tyrosine phosphorylation, the HGF receptor associates with the Shc adaptor, via the SH2 domain. Site-directed mutagenesis of the HGF receptor indicates...

  16. BnEPFL6, an EPIDERMAL PATTERNING FACTOR-LIKE (EPFL) secreted peptide gene, is required for filament elongation in Brassica napus.

    Huang, Yi; Tao, Zhangsheng; Liu, Qiong; Wang, Xinfa; Yu, Jingyin; Liu, Guihua; Wang, Hanzhong

    2014-07-01

    Inflorescence architecture, pedicel length and stomata patterning in Arabidopsis thaliana are specified by inter-tissue communication mediated by ERECTA and its signaling ligands in the EPIDERMAL PATTERNING FACTOR-LIKE (EPFL) family of secreted cysteine-rich peptides. Here, we identified and characterized BnEPFL6 from Brassica napus. Heterologous expression of this gene under the double enhanced CaMV promoter (D35S) in Arabidopsis resulted in shortened stamen filaments, filaments degradation, and reduced filament cell size that displayed down-regulated expression of AHK2, in which phenotypic variation of ahk2-1 mutant presented highly consistent with that of BnEPFL6 transgenic lines. Especially, the expression level of BnEPFL6 in the shortened filaments of four B. napus male sterile lines (98A, 86A, SA, and Z11A) was similar to that of BnEPFL6 in the transgenic Arabidopsis lines. The activity of pBnEPFL6.2::GUS was intensive in the filaments of transgenic lines. These observations reveal that BnEPFL6 plays an important role in filament elongation and may also affect organ morphology and floral organ specification via a BnEPFL6-mediated cascade.

  17. Polycystic Ovary Syndrome and Increased Soluble Tumor Necrosis Factor Like Weak Inducer of Apoptosis Levels Are Independent Predictors of Dyslipidemia in Youth.

    Erkenekli, Kudret; Oztas, Efser; Kuscu, Elif; Keskin, Uğur; Kurt, Yasemin Gulcan; Tas, Ahmet; Yilmaz, Nafiye

    2017-01-01

    Dyslipidemia is common in women with polycystic ovary syndrome (PCOS) irrespective of age. Our aim was to investigate soluble tumor necrosis factor like weak inducer of apoptosis (sTWEAK), a cardiovascular risk marker in PCOS, and to determine if it is associated with dyslipidemia in youth. A prospective-observational study was carried out including 35 PCOS patients and 35 healthy controls. Serum sTWEAK levels were measured using commercially available kits. Multiple logistic regression analysis was then performed to verify the statistically significant differences in the possible predictors of dyslipidemia. Serum sTWEAK levels and the percentage of women with dyslipidemia were significantly higher in the PCOS group (p = 0.024 and p dyslipidemia. The percentage of women with PCOS was significantly higher in the dyslipidemic group when compared with controls; 70.7 vs. 20.7%, respectively (p 693 pg/ml; OR 3.810, 95% CI 1.075-13.501, p = 0.038) were independently associated with dyslipidemia. Increased levels of both sTWEAK and PCOS were found to be independently associated with dyslipidemia in youth. © 2016 S. Karger AG, Basel.

  18. Does epidermal growth factor play a role in the action of sucralfate?

    Nexø, Ebba; Poulsen, Steen Seier

    1987-01-01

    Epidermal growth factor (EGF) is a mitogenic peptide synthesized in the submandibular glands and released in saliva. EGF is able to prevent the development of gastrointestinal ulcers in the rat and to accelerate their healing. The present work was undertaken to examine whether Sucralfate acts via...

  19. Blockades of mitogen-activated protein kinase and calcineurin both change fibre-type markers in skeletal muscle culture

    Higginson, James; Wackerhage, Henning; Woods, Niall

    2002-01-01

    A and mitogen-activated protein kinase kinase (MEK1/2) blockade with U0126 upon myosin heavy chain (MHC) isoform mRNA levels and activities of metabolic enzymes after 1 day, 3 days and 7 days of treatment in primary cultures of spontaneously twitching rat skeletal muscle. U0126 treatment significantly decreased......Activation of either the calcineurin or the extracellular signal-regulated kinase (ERK1/2) pathway increases the percentage of slow fibres in vivo suggesting that both pathways can regulate fibre phenotypes in skeletal muscle. We investigated the effect of calcineurin blockade with cyclosporin...

  20. Purification and characterization of a mucin specific mycelial lectin from Aspergillus gorakhpurensis: application for mitogenic and antimicrobial activity.

    Ram Sarup Singh

    Full Text Available Lectins are carbohydrate binding proteins or glycoproteins that bind reversibly to specific carbohydrates present on the apposing cells, which are responsible for their ability to agglutinate red blood cells, lymphocytes, fibroblasts, etc. Interest in lectins has been intensified due to their carbohydrate specificity as they can be valuable reagents for the investigation of cell surface sugars, purification and characterization of glycoproteins. The present study reports the purification, characterization and evaluation of mitogenic and antimicrobial potential of a mycelial lectin from Aspergillus gorakhpurensis.Affinity chromatography on mucin-sepharose column was carried out for purification of Aspergillus gorakhpurensis lectin. The lectin was characterized for physico-chemical parameters. Mitogenic potential of the lectin was evaluated against splenocytes of Swiss albino mice by MTT assay. Antimicrobial activity of the purified lectin has also been evaluated by disc diffusion assay.Single-step affinity purification resulted in 18.6-fold purification of the mycelial lectin. The molecular mass of the lectin was found to be 70 kDa and it was composed of two subunits of 34.8 kDa as determined by gel filtration chromatography, SDS-PAGE and MALDI-TOF analysis. pH optima of the lectin was found to be 6.5-9.5, while optimum temperature for lectin activity was 20-30 °C. Lectin was stable within a pH range of 7.0-10.5 and showed fair thermostability. EDTA did not affect lectin activity whereas it was found susceptible to the denaturants tested. MTT assay revealed strong mitogenic potential of A. gorakhpurensis lectin at a concentration upto 150 µg/mL. Antimicrobial activity assay showed its potent antibacterial activity against Bacillus cereus, Staphylococcous aureus and Escherichia coli and marginal antifungal activity against Saccharomyces cerevisiae.This is the first report on the mitogenic and antimicrobial potential of Aspergillus gorakhpurensis

  1. AMP N1-Oxide, a Unique Compound of Royal Jelly, Induces Neurite Outgrowth from PC12 Vells via Signaling by Protein Kinase A Independent of that by Mitogen-Activated Protein Kinase

    Noriko Hattori

    2010-01-01

    Full Text Available Earlier we identified adenosine monophosphate (AMP N1-oxide as a unique compound of royal jelly (RJ that induces neurite outgrowth (neuritegenesis from cultured rat pheochromocytoma PC12 cells via the adenosine A2A receptor. Now, we found that AMP N1-oxide stimulated the phosphorylation of not only mitogen-activated protein kinase (MAPK but also that of cAMP/calcium-response element-binding protein (CREB in a dose-dependent manner. Inhibition of MAPK activation by a MEK inhibitor, PD98059, did not influence the AMP N1-oxide-induced neuritegenesis, whereas that of protein kinase A (PKA by a selective inhibitor, KT5720, significantly reduced neurite outgrowth. AMP N1-oxide also had the activity of suppressing the growth of PC12 cells, which correlated well with the neurite outgrowth-promoting activity. KT5720 restored the growth of AMP N1-oxide-treated PC12 cells. It is well known that nerve growth factor suppresses proliferation of PC12 cells before causing stimulation of neuronal differentiation. Thus, AMP N1-oxide elicited neuronal differentiation of PC12 cells, as evidenced by generation of neurites, and inhibited cell growth through adenosine A2A receptor-mediated PKA signaling, which may be responsible for characteristic actions of RJ.

  2. Tumor Necrosis Factor-Like Weak Inducer of Apoptosis Promotes Hepatic Stellate Cells Migration via Canonical NF-κB/MMP9 Pathway.

    Mingcui Xu

    Full Text Available In the liver, the signal and function of tumor necrosis factor-like weak inducer of apoptosis (TWEAK have mainly been assessed in association with liver regeneration. However, the effects of TWEAK on liver fibrosis have not been fully elucidated. To investigate the effects of TWEAK on human hepatic stellate cells (HSCs and to explore the relevant potential mechanisms, human HSCs line-LX-2 were cultured with TWEAK. Cell migration was detected by transwell assay; cell viability was evaluated by Cell Counting Kit-8; the expression of MMP1, MMP2, MMP3, MMP7, MMP8, MMP9, MMP10, MMP11, MMP12, MMP13 gene was identified by quantitative real-time polymerase chain reaction and western blotting; the activity of matrix metalloproteinases (MMPs was tested by enzyme-linked immuno sorbent assay; small interfering RNA transfection was applied for depletion of MMP9 and p65. The result of transwell assay revealed that TWEAK promoted LX-2 migration. Subsequently, our data testified that the expression and activity of MMP9 was induced by TWEAK in LX-2 cells, which enhanced the migration. Furthermore, our findings showed that TWEAK upregulated the phosphorylation of IκBα and p65 protein to increase MMP9 expression in LX-2 cells. Meanwhile, the alpha-smooth muscle actin, vimentin and desmin expression were upregulated following TWEAK treatment. The results in the present study revealed that TWEAK promotes HSCs migration via canonical NF-κB/MMP9 pathway, which possibly provides a molecular basis targeting TWEAK for the therapy of liver fibrosis.

  3. Chemokine-like factor-like MARVEL transmembrane domain-containing 3 expression is associated with a favorable prognosis in esophageal squamous cell carcinoma.

    Han, Tianci; Shu, Tianci; Dong, Siyuan; Li, Peiwen; Li, Weinan; Liu, Dali; Qi, Ruiqun; Zhang, Shuguang; Zhang, Lin

    2017-05-01

    Decreased expression of human chemokine-like factor-like MARVEL transmembrane domain-containing 3 (CMTM3) has been identified in a number of human tumors and tumor cell lines, including gastric and testicular cancer, and PC3, CAL27 and Tca-83 cell lines. However, the association between CMTM3 expression and the clinicopathological features and prognosis of esophageal squamous cell carcinoma (ESCC) patients remains unclear. The aim of the present study was to investigate the correlation between CMTM3 expression and clinicopathological parameters and prognosis in ESCC. CMTM3 mRNA and protein expression was analyzed in ESCC and paired non-tumor tissues by quantitative real-time polymerase chain reaction, western blotting and immunohistochemical analysis. The Kaplan-Meier method was used to plot survival curves and the Cox proportional hazards regression model was also used for univariate and multivariate survival analysis. The results revealed that CMTM3 mRNA and protein expression levels were lower in 82.5% (30/40) and 75% (30/40) of ESCC tissues, respectively, when compared with matched non-tumor tissues. Statistical analysis demonstrated that CMTM3 expression was significantly correlated with lymph node metastasis (P=0.002) and clinical stage (P<0.001) in ESCC tissues. Furthermore, the survival time of ESCC patients exhibiting low CMTM3 expression was significantly shorter than that of ESCC patients exhibiting high CMTM3 expression (P=0.01). In addition, Kaplan-Meier survival analysis revealed that the overall survival time of patients exhibiting low CMTM3 expression was significantly decreased compared with patients exhibiting high CMTM3 expression (P=0.010). Cox multivariate analysis indicated that CMTM3 protein expression was an independent prognostic predictor for ESCC after resection. This study indicated that CMTM3 expression is significantly decreased in ESCC tissues and CMTM3 protein expression in resected tumors may present an effective prognostic

  4. Tumor necrosis factor-like weak inducer of apoptosis (TWEAK) enhances vascular and renal damage induced by hyperlipidemic diet in ApoE-knockout mice.

    Muñoz-García, Begoña; Moreno, Juan Antonio; López-Franco, Oscar; Sanz, Ana Belén; Martín-Ventura, José Luis; Blanco, Julia; Jakubowski, Aniela; Burkly, Linda C; Ortiz, Alberto; Egido, Jesús; Blanco-Colio, Luis Miguel

    2009-12-01

    Tumor necrosis factor-like weak inducer of apoptosis (TWEAK) is a member of the tumor necrosis factor superfamily of cytokines. TWEAK binds and activates the Fn14 receptor, and may regulate apoptosis, inflammation, and angiogenesis, in different pathological conditions. We have evaluated the effect of exogenous TWEAK administration as well as the role of endogenous TWEAK on proinflammatory cytokine expression and vascular and renal injury severity in hyperlipidemic ApoE-knockout mice. ApoE(-/-) mice were fed with hyperlipidemic diet for 4 to 10 weeks, then randomized and treated with saline (controls), TWEAK (10 microg/kg/d), anti-TWEAK neutralizing mAb (1000 microg/kg/d), TWEAK plus anti-TWEAK antibody (10 microg TWEAK +1000 microg anti-TWEAK/kg/d), or nonspecific IgG (1000 microg/kg/d) daily for 9 days. In ApoE(-/-) mice, exogenous TWEAK administration in ApoE(-/-) mice induced activation of NF-kappaB, a key transcription factor implicated in the regulation of the inflammatory response, in vascular and renal lesions. Furthermore, TWEAK treatment increased chemokine expression (RANTES and MCP-1), as well as macrophage infiltration in atherosclerotic plaques and renal lesions. These effects were associated with exacerbation of vascular and renal damage. Conversely, treatment of ApoE(-/-) mice with an anti-TWEAK blocking mAb decreased NF-kappaB activation, proinflammatory cytokine expression, macrophage infiltration, and vascular and renal injury severity, indicating a pathological role for endogenous TWEAK. Finally, in murine vascular smooth muscle cells or tubular cells, either ox-LDL or TWEAK treatment increased expression and secretion of both RANTES and MCP-1. Furthermore, ox-LDL and TWEAK synergized for induction of MCP-1 and RANTES expression and secretion. Our results suggest that TWEAK exacerbates the inflammatory response associated with a high lipid-rich diet. TWEAK may be a novel therapeutic target to prevent vascular and renal damage associated with

  5. ASH1L Suppresses Matrix Metalloproteinase through Mitogen-activated Protein Kinase Signaling Pathway in Pulpitis.

    Bei, Yin; Tianqian, Hui; Fanyuan, Yu; Haiyun, Luo; Xueyang, Liao; Jing, Yang; Chenglin, Wang; Ling, Ye

    2017-02-01

    Pulpitis is an inflammation of dental pulp produced by a response to external stimuli. The response entails substantial cellular and molecular activities. Both genetic and epigenetic regulators contribute to the occurrence of pulpitis. However, the epigenetic mechanisms are still poorly understood. In this research, we studied the role of the absent, small, or homeotic-like (ASH1L) gene in the process of pulpitis. Human dental pulp cells (HDPCs) were stimulated with proinflammatory cytokine tumor necrosis factor alpha (TNF-α). Gene expression profiling was performed to assess the occurrence of epigenetic regulators. Pulp tissue from rat experimental pulpitis was subjected to immunofluorescence to detect the occurrence of ASH1L and trimethylation of lysine 4 histone 3 (H3K4me3). The presence of ASH1L in HDPCs that had been generated by TNF-α stimulation was analyzed by Western blot procedures and cellular immunofluorescence. Once detected, ASH1L was silenced through the use of specific small interfering RNA. The effects of ASH1L on the occurrence and operation of matrix metalloproteinases (MMPs) were then tested by analysis of quantitative polymerase chain reactions, Western blotting, and zymography. Chromatin immunoprecipitation was performed to detect whether ASH1L and H3K4me3 were present in the promoter regions of MMPs. We then used Western blot procedures to examine the nuclear factor kappa B and the mitogen-activated protein kinase (MAPK) responses to the silencing of ASH1L. We also examined the specific pathway involved in ASH1L regulation of the MMPs. After stimulating HDPCs with TNF-α, ASH1L emerged as 1 of the most strongly induced epigenetic mediators. We found that TNF-α treatment induced the expression of ASH1L through the nuclear factor kappa B and MAPK signal pathways. ASH1L was found in both the nucleus and the cytoplasm. TNF-α treatment was particularly active in inducing the accumulation of ASH1L in cellular cytoplasm. As is also consistent

  6. Detection of proliferating cell nuclear antigens and interleukin-2 beta receptor molecules on mitogen- and antigen-stimulated lymphocytes.

    Hesketh, J; Dobbelaere, D; Griffin, J F; Buchan, G

    1993-01-01

    The expression of interleukin-2 receptors (IL-2R) and proliferating cell nuclear antigens (PCNA) were compared for their usefulness as markers of lymphocyte activation. Heterologous polyclonal (anti-bovine IL-2R) and monoclonal (anti-human PCNA) antibodies were used to detect the expression of these molecules on activated deer lymphocytes. Both molecules were co-expressed on blast cells which had been activated with mitogen [concanavalin A (Con A)]. There was detectable up-regulation of IL-2R expression in response to antigen [Mycobacterium bovis-derived purified protein derivative (PPD)] stimulation while PCNA expression mimicked lymphocyte transformation (LT) reactivity. PCNA expression was found to more accurately reflect both antigen- and mitogen-activated lymphocyte activation, as estimated by LT activity. The expression of PCNA was used to identify antigen reactive cells from animals exposed to M. bovis. A very low percentage (1.1 +/- 0.4%) of peripheral blood lymphocytes from non-infected animals could be stimulated to express PCNA by in vitro culture with antigen (PPD). Within the infected group both diseased and healthy, 'in-contact', animals expressed significantly higher levels of PCNA upon antigen stimulation. PMID:8104884

  7. Effects of synthetic and naturally occurring flavonoids on mitogen-induced proliferation of human peripheral-blood lymphocytes

    Hirano, Toshihiko; Oka, Kitaro; Kawashima, Etsuko; Akiba, Mitsuo

    1989-01-01

    Examination was made of the effects of 17 synthetic and naturally occurring flavonoids on human lymphocyte proliferation in the presence of concanavalin A as a mitogen. Twelve of the flavonoids examined were mono-hydroxy of methoxy derivatives. The mitogen-induced response of lymphocytes was evaluated from the extent of the incorporation of [ 3 H]thymidine into cells in vitro. All the compounds showed inhibitory effects; 4.5-77.7% of [ 3 H] thymidine incorporation was blocked by an 1.0 μg/ml concentration. The viability of lymphocytes before and after treatment, as assessed by a dye exclusion test, indicated no change, and thus the flavonoids may inhibit DNA synthesis. The flavonoids possessing 5-hydroxyl, 5-methoxyl and 6-methoxyl groups, and those with cyclohexyl instead of phenyl substituent (i.e. 2-cyclohexyl-benzopyran-4-one), showed the greatest inhibition. The inhibitory effect of any one of them was less than one half that of prednisolone, but essentially the same or somewhat exceeding that of bredinine of azathioprine. It would thus appear that the well-known anti-inflammatory effects of flavonoids may possibly arise in part from the inhibition of the proliferative response of lymphocytes

  8. Induced Mitogenic Activity in AML-12 Mouse Hepatocytes Exposed to Low-dose Ultra-Wideband Electromagnetic Radiation

    P. B. Tchounwou

    2005-04-01

    Full Text Available Ultra–wideband (UWB technology has increased with the use of various civilian and military applications. In the present study, we hypothesized that low-dose UWB electromagnetic radiation (UWBR could elicit a mitogenic effect in AML-12 mouse hepatocytes, in vitro. To test this hypothesis, we exposed AML-12 mouse hepatocytes, to UWBR in a specially constructed gigahertz transverse electromagnetic mode (GTEM cell. Cells were exposed to UWBR for 2 h at a temperature of 23°C, a pulse width of 10 ns, a repetition rate of 1 kHz, and field strength of 5-20 kV/m. UWB pulses were triggered by an external pulse generator for UWBR exposure but were not triggered for the sham exposure. We performed an MTT Assay to assess cell viability for UWBR-treated and sham-exposed hepatocytes. Data from viability studies indicated a time-related increase in hepatocytes at time intervals from 8-24 h post exposure. UWBR exerted a statistically significant (p < 0.05 dose-dependent response in cell viability in both serum-treated and serum free medium (SFM -treated hepatocytes. Western blot analysis of hepatocyte lysates demonstrated that cyclin A protein was induced in hepatocytes, suggesting that increased MTT activity after UWBR exposure was due to cell proliferation. This study indicates that UWBR has a mitogenic effect on AML-12 mouse hepatocytes and implicates a possible role for UWBR in hepatocarcinoma.

  9. Suppression of pokeweed mitogen-stimulated immunoglobulin production in patients with rheumatoid arthritis after treatment with total lymphoid irradiation

    Kotzin, B.L.; Strober, S.; Kansas, G.S.; Terrell, C.P.; Engleman, E.G.

    1984-01-01

    Patients with intractable rheumatoid arthritis (RA) were treated with total lymphoid irradiation (TLI, 200 rad). The authors previously reported long-lasting clinical improvement in this group associated with a persistent decrease in circulating Leu-3 (helper subset) T cells and marked impairment of in vitro lymphocyte function. In the present experiments, they studied the mechanisms underlying the decrease in pokeweed mitogen stimulated immunoglobulin (Ig) secretion observed after TLI. Peripheral blood mononuclear cells (PBL) from TLI-treated patients produced 10-fold less Ig (both IgM and IgG) in response to pokeweed mitogen than before radiotherapy. This decrease in Ig production was associated with the presence of suppressor cells in co-culture studies. By using responder cells obtained from normal individuals (allogeneic system), PBL from eight of 12 patients after TLI suppressed Ig synthesis by more than 50%. In contrast, PBL from the same patients before TLI failed to suppress Ig synthesis. PBL with suppressive activity contained suppressor T cells, and the latter cells bore the Leu-2 surface antigen. In 50% of the patients studied suppressor cells were also found in the non-T fraction and were adherent to plastic. Interestingly, the Leu-2 + cells from TLI-treated patients were no more potent on a cell per cell basis than purified Leu-2 + cells obtained before TLI. Additional experiments suggested that the suppression mediated by T cells after TLI is related to the increased ratio of Leu-2 to Leu-3 cells observed after radiotherapy

  10. The N-terminal of a heparin-binding sperm membrane mitogen possess lectin-like sequence

    Mor, Visesato; Chatterjee, Tapati

    2007-01-01

    Glycosaminoglycans like heparin and heparin sulfate in follicular fluid induce changes in the intracellular environment during the spermatozoal functional maturation. We previously reported the isolation, purification and partial characterization of a heparin binding sperm membrane protein (HBSM). In the present study, the amino acids analysis provided evidence of a single sequence, which suggest the homogeneity of the purified HBSM. Fourteen amino acids- 1 A D T I V A V E L D T Y P N 14 -correspond to the amino terminal sequence of Concanavalin A (Con A) and contain 45.2% carbohydrate by weight. HBSM possess mitogenic property on lymphocytes with comparable magnitude to the well-known mitogen; Con A, inducing 83% radiolabel thymidine incorporation in growing lymphocytes. Unlike Con A, there was no agglutination of cell by HBSM upto 5 ng/ml concentration. Interestingly, we found that heparin and chondroitin sulfate-conjugated HBSM inhibit the proliferative activity. Similar effect was also found with an in-house isolate sulfated glycans; G-I (28% sulfate). In contrast, there was no inhibition by the desulfated form; G-ID. Altogether, our data suggest that the mechanism of cell proliferative pathway may be different for HBSM and Con A

  11. Crosstalk between Smad and Mitogen-Activated Protein Kinases for the Regulation of Apoptosis in Cyclosporine A- Induced Renal Tubular Injury

    Hideyuki Iwayama

    2011-10-01

    Full Text Available Background/Aims: It remains elusive whether there is a crosstalk between Smad and mitogen-activated protein kinases (MAPKs and whether it regulates cyclosporine A (CyA-induced apoptosis in renal proximal tubular cells (RPTCs. Methods: The effect of CyA on nuclear translocation of Smad2/3 and MAPKs (measured by Western blotting or immunofluorescence and apoptosis (determined by Hoechst 33258 staining was examined in HK-2 cells. Results: CyA induced apoptosis at 24 h and nuclear translocation of phosphorylated (p-Smad2/3 at 3 h, which was continued till 24 h. CyA enhanced the expression of p-ERK at 1 h, which was continued till 24 h, and of p-p38MAPK at 1–6 h, which returned to control level at 12 h. CyA did not affect JNK. An inhibitor of ERK, PD98059, prevented CyA-induced nuclear translocation of Smad2/3 and apoptosis. An inhibitor of p38MAPK, SB202190, deteriorated CyA-induced nuclear translocation of p-Smad2/3. Epidermal growth factor (EGF activated ERK and p38MAPK but not JNK. EGF-induced activation of MAPKs ameliorated CyA-induced nuclear translocation of p-Smad2/3 and apoptosis. Inhibition of p38MAPK but not of ERK abolished the protective effect of EGF on CyA-induced nuclear translocation of p-Smad2/3 and apoptosis. Conclusion: Crosstalk between R-Smad and p38MAPK/ERK, but not JNK differentially regulates apoptosis in CyA-induced RPTC injury.

  12. Polyclonal activation of rat B cells. I. A single mitogenic signal can stimulate proliferation, but three signals are required for differentiation

    Stunz, L.L.; Feldbush, T.L.

    1986-01-01

    A water-soluble, proteinaceous preparation derived from the cell walls of Salmonella typhimurium Re mutants has recently been tested in this laboratory for its ability to act as a mitogen for rat lymphocytes. This preparation (STM) has been found to be a potent simulator of B lymphocyte proliferation, as measured both by 3 H-TdR incorporation and by cell cycle analysis performed with flow cytofluorometry. STM stimulates approximately 50% of rat B cells to enter cycle. Previous investigations by others have shown that at least two sets of signals are required for B cell differentiation; (a) proliferation signals that may consist of both a stimulator of B cell conversion from G 0 to G 1 and growth factors, and (b) differentiation signals that probably include at least two B cell differentiation factors (BCDF). When STM was tested in a differentiation system it did not drive purified B cells to differentiate to PFC, either alone or when supplemented with a supernatant from concanavalin A-stimulated spleen cells (CAS). However, when both CAS and dextran sulfate (DXS) were supplied to the STM-stimulated cells, a large number of PFC resulted. DXT does not act by stimulating an additional, CAS-responsive B cell subset, since it has only a marginal effect upon 3 H-TdR uptake and does not increase the number of B cells in cycle when used together with STM. The authors that the two agents may be acting sequentially: STM stimulates the B cells to proliferate, and DXS drives the proliferating cells to become responsive to CAS. This suggests that the signals for B cell differentiation must consist of at least three activities: a trigger to stimulate the cells to proliferate, a factor to drive the cells to a BCDF-responsive state, and a BCDF that can drive the cells to secrete antibody

  13. Expression Profiling of Mitogen-Activated Protein Kinase Genes Reveals Their Evolutionary and Functional Diversity in Different Rubber Tree (Hevea brasiliensis Cultivars

    Xiang Jin

    2017-10-01

    Full Text Available Rubber tree (Hevea brasiliensis is the only commercially cultivated plant for producing natural rubber, one of the most essential industrial raw materials. Knowledge of the evolutionary and functional characteristics of kinases in H. brasiliensis is limited because of the long growth period and lack of well annotated genome information. Here, we reported mitogen-activated protein kinases in H. brasiliensis (HbMPKs by manually checking and correcting the rubber tree genome. Of the 20 identified HbMPKs, four members were validated by proteomic data. Protein motif and phylogenetic analyses classified these members into four known groups comprising Thr-Glu-Tyr (TEY and Thr-Asp-Tyr (TDY domains, respectively. Evolutionary and syntenic analyses suggested four duplication events: HbMPK3/HbMPK6, HbMPK8/HbMPK9/HbMPK15, HbMPK10/HbMPK12 and HbMPK11/HbMPK16/HbMPK19. Expression profiling of the identified HbMPKs in roots, stems, leaves and latex obtained from three cultivars with different latex yield ability revealed tissue- and variety-expression specificity of HbMPK paralogues. Gene expression patterns under osmotic, oxidative, salt and cold stresses, combined with cis-element distribution analyses, indicated different regulation patterns of HbMPK paralogues. Further, Ka/Ks and Tajima analyses suggested an accelerated evolutionary rate in paralogues HbMPK10/12. These results revealed HbMPKs have diverse functions in natural rubber biosynthesis, and highlighted the potential possibility of using MPKs to improve stress tolerance in future rubber tree breeding.

  14. Purification of human platelet-derived growth factor

    Raines, E.W.; Ross, R.

    1985-01-01

    The paper describes a method for purification of human platelet-derived growth factor (PDGF) from outdated platelet-rich plasma (PRP) using commonly available laboratory reagents and yielding a mitogen purified 800,000-fold over the starting material. [ 3 H]thymidine incorporation into DNA of cultured cells responsive to PDGF represents the most readily available method to follow its purification and define the biological activity of a purified preparation. Other assays to quantitate PDGF include radioreceptor assay and radioimmunoassay

  15. [Expression of tumor necrosis factor-like weak inducer of apoptosis in patients with gastric cancer and its relationship with nutritional status].

    Lu, Hang; Sun, Yuanshui

    2016-10-25

    To investigate the expression of tumor necrosis factor-like weak inducer of apoptosis (TWEAK) in the serum and the rectus abdominis muscle in patients with gastric cancer and its relationship with the nutritional status. Method Clinical data of 102 patients with gastric cancer (gastric cancer group) and 53 patients with benign abdominal disease (control group) who were admitted to Zhejiang Province People's Hospital from January 2008 to October 2013 were analyzed retrospectively. Enzyme-linked immunosorbent assay(ELISA) was used to detect the serum expression of TWEAK. Reverse transcription polymerase chain reaction (RT-PCR) and Western blot were used to detect the mRNA and protein expression of TWEAK in the rectus abdominis muscle. Relationship between TWEAK expression and nutritional status of gastric cancer patients was examined. The relative expression level of TWEAK protein in serum of gastric cancer group and control group was 0.403±0.065 and 0.148±0.036 respectively. The relative expression of TWEAK mRNA in the rectus abdominis muscle tissue was 0.313±0.089 (gastric cancer group) and 0.118±0.005 (control group). The relative expression of TWEAK protein in the rectus abdominis muscle tissue was 0.197±0.064 (gastric cancer group) and 0.066±0.014 (control group), and the differences were statistically significant (both P=0.000). The high expression of TWEAK (high than median) in rectus abdominis muscle of gastric cancer patients was related to the percentage of more than 10% decline in body weight (P=0.000), the small percentage of ideal body weight at the time of admission (P=0.000), BMInutritional risk screening score (P=0.000), lower prognostic nutrition index (P=0.000) and serum albumin gastric cancer patients up-regulates compared to non-tumor patients. The expression level of TWEAK in the rectus abdominis muscle of gastric cancer patients is closely related to poor nutritional status, suggesting that TWEAK may play a key role in the process of

  16. Aqueous exposure to Aroclor 1254 modulates the mitogenic response of Atlantic salmon anterior kidney T-cells: Indications of short- and long-term immunomodulation

    Iwanowicz, Luke R.; Lerner, Darren T.; Blazer, Vicki S.; McCormick, Stephen D.

    2005-01-01

    Polychlorinated biphenyls (PCBs) exist as persistent organic pollutants in numerous river systems in the United States. Unfortunately, some of these rivers are sites of active Atlantic salmon restoration programs, and polychlorinated biphenyls have been implicated as ancillary factors contributing to failed salmon restoration. Here, we investigate the immediate and chronic effects of intermediate duration aqueous PCB exposure (1 or 10 μg L -1 Aroclor 1254) on the mitogen-stimulated lymphoproliferative response of Atlantic salmon anterior kidney leukocytes (AKLs). A short-term study was designed to examine immunomodulation in Atlantic salmon smolts immediately following 21 days of aqueous exposure, while a long-term study evaluated chronic impacts in the mitogen response in parr 15 months post-exposure as larvae. The proliferative response of AKLs to the mitogens concanavalin A (CON A), phytohemaglutinnin-P (PHA-P), pokeweed mitogen (PWM), and lipopolysaccharide were used as an indice of immunomodulation. The proliferative response to the T-cell mitogens CON A and PHA-P was significantly increased in the 10 μg L -1 group (n = 10; P = 0.043 and 0.002, respectively) immediately following exposure of smolts. Additionally, The PHA-P response was significantly increased in the 1 μg L -1 exposure group (n = 10, P = 0.036). In fish treated as larvae and tested 15 months later, the PHA-P sensitive populations exhibited elevated proliferation in the 1 and 10 μg L -1 groups (n = 12, P -1 treated groups. These results demonstrate an immunomodulatory effect of PCBs on T-cell mitogen sensitive populations of lymphocytes in Atlantic salmon as well as long-term immunomodulation in PHA-P and PWM sensitive populations

  17. Aqueous exposure to Aroclor 1254 modulates the mitogenic response of Atlantic salmon anterior kidney T-cells: indications of short- and long-term immunomodulation.

    Iwanowicz, Luke R; Lerner, Darren T; Blazer, Vicki S; McCormick, Stephen D

    2005-05-15

    Polychlorinated biphenyls (PCBs) exist as persistent organic pollutants in numerous river systems in the United States. Unfortunately, some of these rivers are sites of active Atlantic salmon restoration programs, and polychlorinated biphenyls have been implicated as ancillary factors contributing to failed salmon restoration. Here, we investigate the immediate and chronic effects of intermediate duration aqueous PCB exposure (1 or 10 microgL-1 Aroclor 1254) on the mitogen-stimulated lymphoproliferative response of Atlantic salmon anterior kidney leukocytes (AKLs). A short-term study was designed to examine immunomodulation in Atlantic salmon smolts immediately following 21 days of aqueous exposure, while a long-term study evaluated chronic impacts in the mitogen response in parr 15 months post-exposure as larvae. The proliferative response of AKLs to the mitogens concanavalin A (CON A), phytohemaglutinnin-P (PHA-P), pokeweed mitogen (PWM), and lipopolysaccharide were used as an indice of immunomodulation. The proliferative response to the T-cell mitogens CON A and PHA-P was significantly increased in the 10 microgL-1 group (n=10; P=0.043 and 0.002, respectively) immediately following exposure of smolts. Additionally, The PHA-P response was significantly increased in the 1 microgL-1 exposure group (n=10, P=0.036). In fish treated as larvae and tested 15 months later, the PHA-P sensitive populations exhibited elevated proliferation in the 1 and 10 microgL-1 groups (n=12, P<0.04) relative to the vehicle control while the PWM response was significantly increased (n=12, P=0.036) only in the 10 microgL-1 treated groups. These results demonstrate an immunomodulatory effect of PCBs on T-cell mitogen sensitive populations of lymphocytes in Atlantic salmon as well as long-term immunomodulation in PHA-P and PWM sensitive populations.

  18. Analysis of the Yeast Kinome Reveals a Network of Regulated Protein Localization during Filamentous Growth

    Bharucha, Nikë; Ma, Jun; Dobry, Craig J.; Lawson, Sarah K.; Yang, Zhifen; Kumar, Anuj

    2008-01-01

    The subcellular distribution of kinases and other signaling proteins is regulated in response to cellular cues; however, the extent of this regulation has not been investigated for any gene set in any organism. Here, we present a systematic analysis of protein kinases in the budding yeast, screening for differential localization during filamentous growth. Filamentous growth is an important stress response involving mitogen-activated protein kinase and cAMP-dependent protein kinase signaling m...

  19. Contractions activate hormone-sensitive lipase in rat muscle by protein kinase C and mitogen-activated protein kinase

    Donsmark, Morten; Langfort, Jozef; Holm, Cecilia

    2003-01-01

    and contractions. Adrenaline acts via cAMP-dependent protein kinase (PKA). The signalling mediating the effect of contractions is unknown and was explored in this study. Incubated soleus muscles from 70 g male rats were electrically stimulated to perform repeated tetanic contractions for 5 min. The contraction......Intramuscular triacylglycerol is an important energy store and is also related to insulin resistance. The mobilization of fatty acids from this pool is probably regulated by hormone-sensitive lipase (HSL), which has recently been shown to exist in muscle and to be activated by both adrenaline......-induced activation of HSL was abolished by the protein kinase C (PKC) inhibitors bisindolylmaleimide I and calphostin C and reduced 50% by the mitogen-activated protein kinase kinase (MEK) inhibitor U0126, which also completely blocked extracellular signal-regulated kinase (ERK) 1 and 2 phosphorylation. None...

  20. Context Specificity of Stress-activated Mitogen-activated Protein (MAP) Kinase Signaling: The Story as Told by Caenorhabditis elegans*

    Andrusiak, Matthew G.; Jin, Yishi

    2016-01-01

    Stress-associated p38 and JNK mitogen-activated protein (MAP) kinase signaling cascades trigger specific cellular responses and are involved in multiple disease states. At the root of MAP kinase signaling complexity is the differential use of common components on a context-specific basis. The roundworm Caenorhabditis elegans was developed as a system to study genes required for development and nervous system function. The powerful genetics of C. elegans in combination with molecular and cellular dissections has led to a greater understanding of how p38 and JNK signaling affects many biological processes under normal and stress conditions. This review focuses on the studies revealing context specificity of different stress-activated MAPK components in C. elegans. PMID:26907690

  1. Context Specificity of Stress-activated Mitogen-activated Protein (MAP) Kinase Signaling: The Story as Told by Caenorhabditis elegans.

    Andrusiak, Matthew G; Jin, Yishi

    2016-04-08

    Stress-associated p38 and JNK mitogen-activated protein (MAP) kinase signaling cascades trigger specific cellular responses and are involved in multiple disease states. At the root of MAP kinase signaling complexity is the differential use of common components on a context-specific basis. The roundwormCaenorhabditis eleganswas developed as a system to study genes required for development and nervous system function. The powerful genetics ofC. elegansin combination with molecular and cellular dissections has led to a greater understanding of how p38 and JNK signaling affects many biological processes under normal and stress conditions. This review focuses on the studies revealing context specificity of different stress-activated MAPK components inC. elegans. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  2. p38gamma and p38delta mitogen activated protein kinases (MAPKs, new stars in the MAPK galaxy

    Alejandra eEscós

    2016-04-01

    Full Text Available The protein kinases p38γ and p38δ belong to the p38 mitogen-activated protein kinase (MAPK family. p38MAPK signalling controls many cellular processes and is one of the most conserved mechanisms in eukaryotes for the cellular response to environmental stress and inflammation. Although p38γ and p38δ are widely expressed, it is likely that they perform specific functions in different tissues. Their involvement in human pathologies such as inflammation-related diseases or cancer is starting to be uncovered. In this article we give a general overview and highlight recent advances made in defining the functions of p38γ and p38δ, focusing in innate immunity and inflammation. We consider the potential of the pharmacological targeting of MAPK pathways to treat autoimmune and inflammatory diseases and cancer

  3. The anti-proliferative effect of cation channel blockers in T lymphocytes depends on the strength of mitogenic stimulation.

    Petho, Zoltan; Balajthy, Andras; Bartok, Adam; Bene, Krisztian; Somodi, Sandor; Szilagyi, Orsolya; Rajnavolgyi, Eva; Panyi, Gyorgy; Varga, Zoltan

    2016-03-01

    Ion channels are crucially important for the activation and proliferation of T lymphocytes, and thus, for the function of the immune system. Previous studies on the effects of channel blockers on T cell proliferation reported variable effectiveness due to differing experimental systems. Therefore our aim was to investigate how the strength of the mitogenic stimulation influences the efficiency of cation channel blockers in inhibiting activation, cytokine secretion and proliferation of T cells under standardized conditions. Human peripheral blood lymphocytes were activated via monoclonal antibodies targeting the TCR-CD3 complex and the co-stimulator CD28. We applied the blockers of Kv1.3 (Anuroctoxin), KCa3.1 (TRAM-34) and CRAC (2-Apb) channels of T cells either alone or in combination with rapamycin, the inhibitor of the mammalian target of rapamycin (mTOR). Five days after the stimulation ELISA and flow cytometric measurements were performed to determine IL-10 and IFN-γ secretion, cellular viability and proliferation. Our results showed that ion channel blockers and rapamycin inhibit IL-10 and IFN-γ secretion and cell division in a dose-dependent manner. Simultaneous application of the blockers for each channel along with rapamycin was the most effective, indicating synergy among the various activation pathways. Upon increasing the extent of mitogenic stimulation the anti-proliferative effect of the ion channel blockers diminished. This phenomenon may be important in understanding the fine-tuning of T cell activation. Copyright © 2016 European Federation of Immunological Societies. Published by Elsevier B.V. All rights reserved.

  4. Mitogen-activated protein kinase phosphatase-1 expression in macrophages is controlled by lymphocytes during macrophage activation.

    Luo, Chong; Yang, Xiqiang; Yao, Lan; Jiang, Liping; Liu, Wei; Li, Xin; Wang, Lijia

    2012-01-01

    The viewpoints on the control of innate immune cells by the adaptive immune system during sepsis remain controversial. Mitogen-activated protein kinase phosphatase-1 (MKP-1) is essential to the negative control of innate immunity and suppresses the activation of macrophages by inhibiting activated mitogen-activated protein kinase (MAPK). The purpose of the current study was to observe inflammatory response and macrophage activation in mice with severe combined immunodeficiency (SCID) with endotoxemia and to determine the role of MKP-1 in the control of macrophage activation by the adaptive immune system. Endotoxemia was induced in wild-type and SCID mice by an intraperitoneal injection of lipopolysaccharide (LPS), and all of the SCID mice died. SCID mice produced more inflammatory cytokines than BALB/c mice systemically and locally. TNF-α mRNA expression was higher and MKP-1 mRNA expression was lower in peritoneal macrophages (PMa) from SCID mice compared to PMa from wild-type mice after and even before LPS injection. Thioglycollate-stimulated PMa from wild-type mice were stimulated with LPS in vitro in the presence or absence of pan-T cells. The levels of TNF-α and IL-6 were higher in the supernatants from PMa cultured alone compared to PMa co-cultured with pan-T cells, and PMa MKP-1 mRNA and protein expression were higher when PMa were co-cultured with pan-T cells. Therefore, pan-T cells can up-regulate MKP-1 expression in macrophages and inhibit the secretion of inflammatory cytokines secretion by macrophages. In SCID mice, lymphocyte deficiency, especially T cell deficiency, causes insufficient MKP-1 expression in macrophages, which can be responsible for the severe inflammation and bad prognosis of septic SCID mice. MKP-1 plays an important role in the control of macrophage activation by the adaptive immune system.

  5. T-cell subset alterations and lymphocyte responsiveness to mitogens and antigen during severe primary infection with HIV: a case series of seven consecutive HIV seroconverters

    Pedersen, C; Dickmeiss, E; Gaub, J

    1990-01-01

    Seven consecutive patients who presented with a severe acute mononucleosis-like illness associated with HIV seroconversion were evaluated by T-cell subset enumerations and measurements of lymphocyte transformation responses to mitogens and antigen during both their primary illness and a 1-year...

  6. Mitigation of direct neurotoxic effects of lidocaine and amitriptyline by inhibition of p38 mitogen-activated protein kinase in vitro and in vivo

    Lirk, Philipp; Haller, Ingrid; Myers, Robert R.; Klimaschewski, Lars; Kau, Yi-Chuan; Hung, Yu-Chun; Gerner, Peter

    2006-01-01

    Local anesthetic-induced direct neurotoxicity (paresthesia, failure to regain normal sensory and motor function) is a potentially devastating complication of regional anesthesia. Local anesthetics activate the p38 mitogen-activated protein kinase (MAPK) system, which is involved in apoptotic cell

  7. Transfer RNA species in human lymphocytes stimulated by mitogens and in leukemic cells. [/sup 3/H, /sup 14/C, /sup 32/P tracer techniques

    Griffin, G.D.; Yang, W.K.; Novelli, G.D.

    1976-01-01

    Transfer ribonucleic acid (tRNA) profiles in human lymphocytes stimulated by various mitogens have been compared with profiles from nonstimulated cells and from leukemic cells using reversed-phase chromatography. Comparisons of (/sup 3/H)- or (/sup 11/C)uridine- or (/sup 32/P)phosphate-labeled tRNAs showed that the greatest changes in tRNA composition upon phytohemagglutinin (PHA) stimulation occurred in the first 8 h after mitogen addition. Stimulation of lymphocytes by pokeweed mitogen, anti-human immunoglobulin, or bacterial lipopolysaccharide resulted in tRNA species which showed distinct differences from each other and also from the tRNAs produced by phytohemagglutinin stimulation. Leukemic lymphocyte tRNAs showed the most extensive differences in profile when compared with chromatograms from non-neoplastic cells stimulated by a variety of mitogens. Specific isoaccepting species of tyrosyl-, aspartyl-, and phenylalanyl-tRNAs were also compared in PHA-stimulated and resting lymphocytes and no differences were found. When these same species were studied in leukemic cells, tyrosyl-tRNA profiles were shifted to elute at a lower salt concentration, while the aspartyl-tRNA profile showed a new peak not present in noncancerous cells.

  8. The immunodeficiency of bone marrow-transplanted patients. The effect of patient lymphocytes on the response of donor lymphocytes to mitogens and allogeneic cells

    Ødum, Niels; Hofmann, B; Platz, P

    1985-01-01

    Lymphocytes from patients after bone marrow transplantation (BMT) are in most cases predominantly of the Leu-2+ (cytotoxic/suppressor) phenotypes and are almost unresponsive to mitogens. In contrast, normal Leu-3+-depleted, Leu-2+-enriched lymphocyte suspensions retain approximately 50...

  9. PSM/SH2-B distributes selected mitogenic receptor signals to distinct components in the PI3-kinase and MAP kinase signaling pathways.

    Deng, Youping; Xu, Hu; Riedel, Heimo

    2007-02-15

    The Pro-rich, PH, and SH2 domain containing mitogenic signaling adapter PSM/SH2-B has been implicated as a cellular partner of various mitogenic receptor tyrosine kinases and related signaling mechanisms. Here, we report in a direct comparison of three peptide hormones, that PSM participates in the assembly of distinct mitogenic signaling complexes in response to insulin or IGF-I when compared to PDGF in cultured normal fibroblasts. The complex formed in response to insulin or IGF-I involves the respective peptide hormone receptor and presumably the established components leading to MAP kinase activation. However, our data suggest an alternative link from the PDGF receptor via PSM directly to MEK1/2 and consequently also to p44/42 activation, possibly through a scaffold protein. At least two PSM domains participate, the SH2 domain anticipated to link PSM to the respective receptor and the Pro-rich region in an association with an unidentified downstream component resulting in direct MEK1/2 and p44/42 regulation. The PDGF receptor signaling complex formed in response to PDGF involves PI 3-kinase in addition to the same components and interactions as described for insulin or IGF-I. PSM associates with PI 3-kinase via p85 and in addition the PSM PH domain participates in the regulation of PI 3-kinase activity, presumably through membrane interaction. In contrast, the PSM Pro-rich region appears to participate only in the MAP kinase signal. Both pathways contribute to the mitogenic response as shown by cell proliferation, survival, and focus formation. PSM regulates p38 MAP kinase activity in a pathway unrelated to the mitogenic response.

  10. Transforming growth factor alpha, Shope fibroma growth factor, and vaccinia growth factor can replace myxoma growth factor in the induction of myxomatosis in rabbits.

    Opgenorth, A; Nation, N; Graham, K; McFadden, G

    1993-02-01

    The epidermal growth factor (EGF) homologues encoded by vaccinia virus, myxoma virus, and malignant rabbit fibroma virus have been shown to contribute to the pathogenicity of virus infection upon inoculation of susceptible hosts. However, since the primary structures of these growth factors and the disease profiles induced by different poxvirus genera vary substantially, the degree to which the various EGF homologues perform similar roles in viral pathogenesis remains unclear. In order to determine whether different EGF-like growth factors can perform qualitatively similar functions in the induction of myxomatosis in rabbits, we created recombinant myxoma virus variants in which the native growth factor, myxoma growth factor (MGF), was disrupted and replaced with either vaccinia virus growth factor, Shope fibroma growth factor, or rat transforming growth factor alpha. Unlike the control virus containing an inactivated MGF gene, which caused marked attenuation of the disease syndrome and substantially less proliferation of the epithelial cell layers in the conjunctiva and respiratory tract, the recombinant myxoma virus strains expressing heterologous growth factors produced infections which were both clinically and histopathologically indistinguishable from wild-type myxomatosis. We conclude that these poxviral and cellular EGF-like growth factors, which are diverse with respect to primary structure and origin, have similar biological functions in the context of myxoma virus pathogenesis and are mitogenic for the same target cells.

  11. A mitogen-activated protein kinase Tmk3 participates in high osmolarity resistance, cell wall integrity maintenance and cellulase production regulation in Trichoderma reesei.

    Mingyu Wang

    Full Text Available The mitogen-activated protein kinase (MAPK pathways are important signal transduction pathways conserved in essentially all eukaryotes, but haven't been subjected to functional studies in the most important cellulase-producing filamentous fungus Trichoderma reesei. Previous reports suggested the presence of three MAPKs in T. reesei: Tmk1, Tmk2, and Tmk3. By exploring the phenotypic features of T. reesei Δtmk3, we first showed elevated NaCl sensitivity and repressed transcription of genes involved in glycerol/trehalose biosynthesis under higher osmolarity, suggesting Tmk3 participates in high osmolarity resistance via derepression of genes involved in osmotic stabilizer biosynthesis. We also showed significant downregulation of genes encoding chitin synthases and a β-1,3-glucan synthase, decreased chitin content, 'budded' hyphal appearance typical to cell wall defective strains, and increased sensitivity to calcofluor white/Congo red in the tmk3 deficient strain, suggesting Tmk3 is involved in cell wall integrity maintenance in T. reesei. We further observed the decrease of cellulase transcription and production in T. reesei Δtmk3 during submerged cultivation, as well as the presence of MAPK phosphorylation sites on known transcription factors involved in cellulase regulation, suggesting Tmk3 is also involved in the regulation of cellulase production. Finally, the expression of cell wall integrity related genes, the expression of cellulase coding genes, cellulase production and biomass accumulation were compared between T. reesei Δtmk3 grown in solid state media and submerged media, showing a strong restoration effect in solid state media from defects resulted from tmk3 deletion. These results showed novel physiological processes that fungal Hog1-type MAPKs are involved in, and present the first experimental investigation of MAPK signaling pathways in T. reesei. Our observations on the restoration effect during solid state cultivation suggest

  12. A Mitogen-Activated Protein Kinase Tmk3 Participates in High Osmolarity Resistance, Cell Wall Integrity Maintenance and Cellulase Production Regulation in Trichoderma reesei

    Wang, Mingyu; Zhao, Qiushuang; Yang, Jinghua; Jiang, Baojie; Wang, Fangzhong; Liu, Kuimei; Fang, Xu

    2013-01-01

    The mitogen-activated protein kinase (MAPK) pathways are important signal transduction pathways conserved in essentially all eukaryotes, but haven't been subjected to functional studies in the most important cellulase-producing filamentous fungus Trichoderma reesei. Previous reports suggested the presence of three MAPKs in T. reesei: Tmk1, Tmk2, and Tmk3. By exploring the phenotypic features of T. reesei Δtmk3, we first showed elevated NaCl sensitivity and repressed transcription of genes involved in glycerol/trehalose biosynthesis under higher osmolarity, suggesting Tmk3 participates in high osmolarity resistance via derepression of genes involved in osmotic stabilizer biosynthesis. We also showed significant downregulation of genes encoding chitin synthases and a β-1,3-glucan synthase, decreased chitin content, ‘budded’ hyphal appearance typical to cell wall defective strains, and increased sensitivity to calcofluor white/Congo red in the tmk3 deficient strain, suggesting Tmk3 is involved in cell wall integrity maintenance in T. reesei. We further observed the decrease of cellulase transcription and production in T. reesei Δtmk3 during submerged cultivation, as well as the presence of MAPK phosphorylation sites on known transcription factors involved in cellulase regulation, suggesting Tmk3 is also involved in the regulation of cellulase production. Finally, the expression of cell wall integrity related genes, the expression of cellulase coding genes, cellulase production and biomass accumulation were compared between T. reesei Δtmk3 grown in solid state media and submerged media, showing a strong restoration effect in solid state media from defects resulted from tmk3 deletion. These results showed novel physiological processes that fungal Hog1-type MAPKs are involved in, and present the first experimental investigation of MAPK signaling pathways in T. reesei. Our observations on the restoration effect during solid state cultivation suggest that T. reesei

  13. Economic Limits to Corporate Growth in America

    2006-12-01

    data ranges. Such simple models are certainly open to criticism , particularly that they do not incorporate factors likely to drive the growth...involved. This relationship stipulates higher expected returns for riskier endeavors. In the capital asset pricing model ( CAPM ), the relationship...premium associated with taking on risk levels different than that of the market. A model like the CAPM predicts that the only risk rewarded in the

  14. JNK mitogen-activated protein kinase limits calcium-dependent chloride secretion across colonic epithelial cells.

    Donnellan, Fergal

    2010-01-01

    Neuroimmune agonists induce epithelial Cl(-) secretion through elevations in intracellular Ca2+ or cAMP. Previously, we demonstrated that epidermal growth factor receptor (EGFR) transactivation and subsequent ERK MAPK activation limits secretory responses to Ca2+-dependent, but not cAMP-dependent, agonists. Although JNK MAPKs are also expressed in epithelial cells, their role in regulating transport function is unknown. Here, we investigated the potential role for JNK in regulating Cl(-) secretion in T(84) colonic epithelial cells. Western blot analysis revealed that a prototypical Ca2+-dependent secretagogue, carbachol (CCh; 100 microM), induced phosphorylation of both the 46-kDa and 54-kDa isoforms of JNK. This effect was mimicked by thapsigargin (TG), which specifically elevates intracellular Ca2+, but not by forskolin (FSK; 10 microM), which elevates cAMP. CCh-induced JNK phosphorylation was attenuated by the EGFR inhibitor, tyrphostin-AG1478 (1 microM). Pretreatment of voltage-clamped T(84) cells with SP600125 (2 microM), a specific JNK inhibitor, potentiated secretory responses to both CCh and TG but not to FSK. The effects of SP600125 on CCh-induced secretion were not additive with those of the ERK inhibitor, PD98059. Finally, in apically permeabilized T(84) cell monolayers, SP600125 potentiated CCh-induced K+ conductances but not Na+\\/K+ATPase activity. These data demonstrate a novel role for JNK MAPK in regulating Ca2+ but not cAMP-dependent epithelial Cl(-) secretion. JNK activation is mediated by EGFR transactivation and exerts its antisecretory effects through inhibition of basolateral K+ channels. These data further our understanding of mechanisms regulating epithelial secretion and underscore the potential for exploitation of MAPK-dependent signaling in treatment of intestinal transport disorders.

  15. Asthmatic airway smooth muscle CXCL10 production: mitogen-activated protein kinase JNK involvement

    Alrashdan, Yazan A.; Alkhouri, Hatem; Chen, Emily; Lalor, Daniel J.; Poniris, Maree; Henness, Sheridan; Brightling, Christopher E.; Burgess, Janette K.; Armour, Carol L.; Ammit, Alaina J.

    2012-01-01

    CXCL10 (IP10) is involved in mast cell migration to airway smooth muscle (ASM) bundles in asthma. We aimed to investigate the role of cytokine-induced MAPK activation in CXCL10 production by ASM cells from people with and without asthma. Confluent growth-arrested ASM cells were treated with inhibitors of the MAPKs ERK, p38, and JNK and transcription factor NF-κB, or vehicle, and stimulated with IL-1β, TNF-α, or IFN-γ, alone or combined (cytomix). CXCL10 mRNA and protein, JNK, NF-κB p65 phosphorylation, and Iκ-Bα protein degradation were assessed using real-time PCR, ELISA, and immunoblotting, respectively. Cytomix, IL-1β, and TNF-α induced CXCL10 mRNA expression more rapidly in asthmatic than nonasthmatic ASM cells. IL-1β and/or TNF-α combined with IFN-γ synergistically increased asthmatic ASM cell CXCL10 release. Inhibitor effects were similar in asthmatic and nonasthmatic cells, but cytomix-induced release was least affected, with only JNK and NF-κB inhibitors halving it. Notably, JNK phosphorylation was markedly less in asthmatic compared with nonasthmatic cells. However, in both, the JNK inhibitor SP600125 reduced JNK phosphorylation and CXCL10 mRNA levels but did not affect CXCL10 mRNA stability or Iκ-Bα degradation. Together, the JNK and NF-κB inhibitors completely inhibited their CXCL10 release. We concluded that, in asthmatic compared with nonasthmatic ASM cells, JNK activation was reduced and CXCL10 gene expression was more rapid following cytomix stimulation. However, in both, JNK activation did not regulate early events leading to NF-κB activation. Thus JNK and NF-κB provide independent therapeutic targets for limiting CXCL10 production and mast cell migration to the ASM in asthma. PMID:22387292

  16. Activation of ERK mitogen-activated protein kinase in human cells by the mycotoxin patulin

    Wu, T.-S.; Yu, F.-Y.; Su, C.-C.; Kan, J.-C.; Chung, C.-P.; Liu, B.-H.

    2005-01-01

    Patulin (PAT), a mycotoxin produced by certain species of Penicillium and Aspergillus, is often detectable in moldy fruits and their derivative products. PAT led to a concentration-dependent and time-dependent increase in phosphorylation of extracellular signal-regulated protein kinases 1 and 2 (ERK1/2) in human embryonic kidney (HEK293) cells, human peripheral blood mononuclear cells (PBMCs), and Madin-Darby canine kidney (MDCK) cells. Exposure of HEK293 cells to concentrations above 5 μM PAT for 30 min induced ERK1/2 phosphorylation; activation of ERK1/2 was also observed after 24 h incubation with 0.05 μM of PAT. Treatment of human PBMCs for 30 min with 30 μM PAT dramatically increased the phosphorylated ERK1/2 levels. Both MEK1/2 inhibitors, U0126 and PD98059, suppressed ERK1/2 activation in either HEK293 or MDCK cells. In HEK293 cells, U0126-mediated inhibition of PAT-induced ERK1/2 phosphorylation resulted in a significant decrease in levels of DNA damage, expressed as tail moment values, in the single cell gel electrophoresis assay. Conversely, U0126 did not affect cell viability, lactate dehydrogenase release, and the DNA synthesis rate in PAT-treated cultures. Exposure of HEK293 cells for 90 min to 15 μM PAT elevated the levels of early growth response gene-1 (egr-1) mRNA, but not of c-fos, fosB, and junB mRNAs. These results indicate that in human cells, PAT causes a rapid and persistent activation of ERK1/2 and this signaling pathway plays an important role in mediating PAT-induced DNA damage and egr-1 gene expression

  17. PEDF-derived peptide promotes skeletal muscle regeneration through its mitogenic effect on muscle progenitor cells.

    Ho, Tsung-Chuan; Chiang, Yi-Pin; Chuang, Chih-Kuang; Chen, Show-Li; Hsieh, Jui-Wen; Lan, Yu-Wen; Tsao, Yeou-Ping

    2015-08-01

    In response injury, intrinsic repair mechanisms are activated in skeletal muscle to replace the damaged muscle fibers with new muscle fibers. The regeneration process starts with the proliferation of satellite cells to give rise to myoblasts, which subsequently differentiate terminally into myofibers. Here, we investigated the promotion effect of pigment epithelial-derived factor (PEDF) on muscle regeneration. We report that PEDF and a synthetic PEDF-derived short peptide (PSP; residues Ser(93)-Leu(112)) induce satellite cell proliferation in vitro and promote muscle regeneration in vivo. Extensively, soleus muscle necrosis was induced in rats by bupivacaine, and an injectable alginate gel was used to release the PSP in the injured muscle. PSP delivery was found to stimulate satellite cell proliferation in damaged muscle and enhance the growth of regenerating myofibers, with complete regeneration of normal muscle mass by 2 wk. In cell culture, PEDF/PSP stimulated C2C12 myoblast proliferation, together with a rise in cyclin D1 expression. PEDF induced the phosphorylation of ERK1/2, Akt, and STAT3 in C2C12 myoblasts. Blocking the activity of ERK, Akt, or STAT3 with pharmacological inhibitors attenuated the effects of PEDF/PSP on the induction of C2C12 cell proliferation and cyclin D1 expression. Moreover, 5-bromo-2'-deoxyuridine pulse-labeling demonstrated that PEDF/PSP stimulated primary rat satellite cell proliferation in myofibers in vitro. In summary, we report for the first time that PSP is capable of promoting the regeneration of skeletal muscle. The signaling mechanism involves the ERK, AKT, and STAT3 pathways. These results show the potential utility of this PEDF peptide for muscle regeneration. Copyright © 2015 the American Physiological Society.

  18. Protein structure of fetal antigen 1 (FA1). A novel circulating human epidermal-growth-factor-like protein expressed in neuroendocrine tumors and its relation to the gene products of dlk and pG2

    Jensen, Charlotte Harken; Krogh, Thomas N; Højrup, Peter

    1994-01-01

    The present paper describes the primary structure, glycosylation and tissue localization of fetal antigen 1 (FA1) isolated from second-trimester human amniotic fluid. FA1 is a single-chained, heterogeneous glycoprotein of 225-262 amino acid residues. FA1 has six well conserved epidermal...... extends with minor corrections to the human adrenal-specific mRNA, pG2 as well. Immunohistochemical analysis demonstrated the presence of FA1 in 10 out of 14 lung tumors containing neuroendocrine elements, and in the placental villi where FA1 was exclusively seen in stromal cells in close contact...... to the vascular structure. In the pancreas, FA1 co-localized with insulin in the insulin secretory granules of the beta cells within the islets of Langerhans. Our findings suggest that FA1 is synthesized as a membrane anchored protein and released into the circulation after enzymic cleavage, and that circulating...

  19. Heat Shock Proteins and Mitogen-activated Protein Kinases in Steatotic Livers Undergoing Ischemia-Reperfusion: Some Answers

    Massip-Salcedo, Marta; Casillas-Ramirez, Araní; Franco-Gou, Rosah; Bartrons, Ramón; Ben Mosbah, Ismail; Serafin, Anna; Roselló-Catafau, Joan; Peralta, Carmen

    2006-01-01

    Ischemic preconditioning protects steatotic livers against ischemia-reperfusion (I/R) injury, but just how this is achieved is poorly understood. Here, I/R or preconditioning plus I/R was induced in steatotic and nonsteatotic livers followed by investigating the effect of pharmacological treatments that modulate heat shock proteins (HSPs) and mitogen-activated protein kinases (MAPKs). MAPKs, HSPs, protein kinase C, and transaminase levels were measured after reperfusion. We report that preconditioning increased HSP72 and heme-oxygenase-1 (HO-1) at 6 and 24 hours of reperfusion, respectively. Unlike nonsteatotic livers, steatotic livers benefited from HSP72 activators (geranylgeranylacetone) throughout reperfusion. This protection seemed attributable to HO-1 induction. In steatotic livers, preconditioning and geranylgeranylacetone treatment (which are responsible for HO-1 induction) increased protein kinase C activity. HO-1 activators (cobalt(III) protoporphyrin IX) protected both liver types. Preconditioning reduced p38 MAPK and c-Jun N-terminal kinase (JNK), resulting in HSP72 induction though HO-1 remained unmodified. Like HSP72, both p38 and JNK appeared not to be crucial in preconditioning, and inhibitors of p38 (SB203580) and JNK (SP600125) were less effective against hepatic injury than HO-1 activators. These results provide new data regarding the mechanisms of preconditioning and may pave the way to the development of new pharmacological strategies in liver surgery. PMID:16651615

  20. Adult-onset hyperthyroidism impairs spatial learning: possible involvement of mitogen-activated protein kinase signaling pathways.

    Bitiktaş, Soner; Kandemir, Başak; Tan, Burak; Kavraal, Şehrazat; Liman, Narin; Dursun, Nurcan; Dönmez-Altuntaş, Hamiyet; Aksan-Kurnaz, Işil; Suer, Cem

    2016-08-03

    Given evidence that mitogen-activated protein kinase (MAPK) activation is part of the nongenomic actions of thyroid hormones, we investigated the possible consequences of hyperthyroidism for the cognitive functioning of adult rats. Young adult rats were treated with L-thyroxine or saline. Twenty rats in each group were exposed to Morris water maze testing, measuring their performance in a hidden-platform spatial task. In a separate set of rats not exposed to Morris water maze testing (untrained rats), the expression and phosphorylated levels of p38-MAPK and of its two downstream effectors, Elk-1 and cAMP response element-binding protein, were evaluated using quantitative reverse transcriptase-PCR and western blotting. Rats with hyperthyroidism showed delayed acquisition of learning compared with their wild-type counterparts, as shown by increased escape latencies and distance moved on the last two trials of daily training in the water maze. The hyperthyroid rats, however, showed no difference during probe trials. Western blot analyses of the hippocampus showed that hyperthyroidism increased phosphorylated p38-MAPK levels in untrained rats. Although our study is correlative in nature and does not exclude the contribution of other molecular targets, our findings suggest that the observed impairments in acquisition during actual learning in rats with hyperthyroidism may result from the increased phosphorylation of p38-MAPK.

  1. Outer Membrane Protein 25 of Brucella Activates Mitogen-Activated Protein Kinase Signal Pathway in Human Trophoblast Cells

    Jing Zhang

    2017-12-01

    Full Text Available Outer membrane protein 25 (OMP25, a virulence factor from Brucella, plays an important role in maintaining the structural stability of Brucella. Mitogen-activated protein kinase (MAPK signal pathway widely exists in eukaryotic cells. In this study, human trophoblast cell line HPT-8 and BALB/c mice were infected with Brucella abortus 2308 strain (S2308 and 2308ΔOmp25 mutant strain. The expression of cytokines and activation of MAPK signal pathway were detected. We found that the expressions of tumor necrosis factor-α, interleukin-1, and interleukin-10 (IL-10 were increased in HPT-8 cells infected with S2308 and 2308ΔOmp25 mutant. S2308 also activated p38 phosphorylation protein, extracellular-regulated protein kinases (ERK, and Jun-N-terminal kinase (JNK from MAPK signal pathway. 2308ΔOmp25 could not activate p38, ERK, and JNK branches. Immunohistochemistry experiments showed that S2308 was able to activate phosphorylation of p38 and ERK in BABL/c mice. However, 2308ΔOmp25 could weakly activate phosphorylation of p38 and ERK. These results suggest that Omp25 played an important role in the process of Brucella activation of the MAPK signal pathway.

  2. Molecular Cloning and Characterization of a P38-Like Mitogen-Activated Protein Kinase from Echinococcus granulosus.

    Lü, Guodong; Li, Jing; Zhang, Chuanshan; Li, Liang; Bi, Xiaojuan; Li, Chaowang; Fan, Jinliang; Lu, Xiaomei; Vuitton, Dominique A; Wen, Hao; Lin, Renyong

    2016-12-01

    Cystic echinococcosis (CE) treatment urgently requires a novel drug. The p38 mitogen-activated protein kinases (MAPKs) are a family of Ser/Thr protein kinases, but still have to be characterized in Echinococcus granulosus . We identified a 1,107 bp cDNA encoding a 368 amino acid MAPK protein (Egp38) in E. granulosus . Egp38 exhibits 2 distinguishing features of p38-like kinases: a highly conserved T-X-Y motif and an activation loop segment. Structural homology modeling indicated a conserved structure among Egp38, EmMPK2, and H. sapiens p38α, implying a common binding mechanism for the ligand domain and downstream signal transduction processing similar to that described for p38α. Egp38 and its phosphorylated form are expressed in the E. granulosus larval stages vesicle and protoscolices during intermediate host infection of an intermediate host. Treatment of in vitro cultivated protoscolices with the p38-MAPK inhibitor ML3403 effectively suppressed Egp38 activity and led to significant protoscolices death within 5 days. Treatment of in vitro-cultivated protoscolices with TGF-β1 effectively induced Egp38 phosphorylation. In summary, the MAPK, Egp38, was identified in E. granulosus , as an anti-CE drug target and participates in the interplay between the host and E. granulosus via human TGF-β1.

  3. An Ime2-like mitogen-activated protein kinase is involved in cellulase expression in the filamentous fungus Trichoderma reesei.

    Chen, Fei; Chen, Xiu-Zhen; Su, Xiao-Yun; Qin, Li-Na; Huang, Zhen-Bang; Tao, Yong; Dong, Zhi-Yang

    2015-10-01

    Eukaryotic mitogen-activated protein kinases (MAPKs) play crucial roles in transducing environmental and developmental signals inside the cell and regulating gene expression, however, the roles of MAPKs remain largely unknown in Trichoderma reesei. T. reesei ime2 (TrIme2) encodes an Ime2-like MAPK in T. reesei. The deletion of the TrIme2 gene led to 90% increase in cellulase activity against filter paper during earlier period time of cellulase induction as well as the extracellular protein production. Compared to the parent strain, the transcriptional levels of the three major cellulase genes cbh1,cbh2, egl1 were increased by about 9 times, 4 times, 2 times, respectively, at 8 h after cellulase induction in the ΔTrIme2 mutant. In addition, the disruption of TrIme2 caused over 50% reduction of the transcript levels of cellulase transcriptional regulators cre1 and xyr1. TrIme2 functions in regulation of the expression of cellulase gene in T.reesei, and is a good candidate for genetically engineering of T. reesei for higher cellulase production.

  4. Riboflavin-Induced Disease Resistance Requires the Mitogen-Activated Protein Kinases 3 and 6 in Arabidopsis thaliana.

    Nie, Shengjun; Xu, Huilian

    2016-01-01

    As a resistance elicitor, riboflavin (vitamin B2) protects plants against a wide range of pathogens. At molecular biological levels, it is important to elucidate the signaling pathways underlying the disease resistance induced by riboflavin. Here, riboflavin was tested to induce resistance against virulent Pseudomonas syringae pv. Tomato DC3000 (Pst DC3000) in Arabidopsis. Results showed that riboflavin induced disease resistance based on MAPK-dependent priming for the expression of PR1 gene. Riboflavin induced transient expression of PR1 gene. However, following Pst DC3000 inoculation, riboflavin potentiated stronger PR1 gene transcription. Further was suggested that the transcript levels of mitogen-activated protein kinases, MPK3 and MPK6, were primed under riboflavin. Upon infection by Pst DC3000, these two enzymes were more strongly activated. The elevated activation of both MPK3 and MPK6 was responsible for enhanced defense gene expression and resistance after riboflavin treatment. Moreover, riboflavin significantly reduced the transcript levels of MPK3 and MPK6 by application of AsA and BAPTA, an H2O2 scavenger and a calcium (Ca2+) scavenger, respectively. In conclusion, MPK3 and MPK6 were responsible for riboflavin-induced resistance, and played an important role in H2O2- and Ca2+-related signaling pathways, and this study could provide a new insight into the mechanistic study of riboflavin-induced defense responses.

  5. Mitogen-activated protein kinase signaling in the heart: angels versus demons in a heart-breaking tale.

    Rose, Beth A; Force, Thomas; Wang, Yibin

    2010-10-01

    Among the myriad of intracellular signaling networks that govern the cardiac development and pathogenesis, mitogen-activated protein kinases (MAPKs) are prominent players that have been the focus of extensive investigations in the past decades. The four best characterized MAPK subfamilies, ERK1/2, JNK, p38, and ERK5, are the targets of pharmacological and genetic manipulations to uncover their roles in cardiac development, function, and diseases. However, information reported in the literature from these efforts has not yet resulted in a clear view about the roles of specific MAPK pathways in heart. Rather, controversies from contradictive results have led to a perception that MAPKs are ambiguous characters in heart with both protective and detrimental effects. The primary object of this review is to provide a comprehensive overview of the current progress, in an effort to highlight the areas where consensus is established verses the ones where controversy remains. MAPKs in cardiac development, cardiac hypertrophy, ischemia/reperfusion injury, and pathological remodeling are the main focuses of this review as these represent the most critical issues for evaluating MAPKs as viable targets of therapeutic development. The studies presented in this review will help to reveal the major challenges in the field and the limitations of current approaches and point to a critical need in future studies to gain better understanding of the fundamental mechanisms of MAPK function and regulation in the heart.

  6. Involvement of protein kinase B and mitogen-activated protein kinases in experimental normothermic liver ischaemia-reperfusion injury.

    Cursio, R; Filippa, N; Miele, C; Van Obberghen, E; Gugenheim, J

    2006-06-01

    This study evaluated the role of protein kinase B (PKB), phosphatidylinositol 3-kinase (PI3-K), Bcl-2-associated death protein (BAD) and mitogen-activated protein kinases (MAPKs) in normothermic ischaemia-reperfusion (IR)-induced apoptosis in rat liver. Rats were divided into two groups that received either phosphate-buffered saline (control) or the caspase inhibitor Z-Asp-2,6-dichorobenzoyloxymethylketone (Z-Asp-cmk), injected intravenously 2 min before the induction of 120 min of normothermic liver ischaemia. Liver apoptosis was assessed by the terminal deoxyribonucleotidyltransferase-mediated dUTP nick end labelling (TUNEL) method. PI3-K, PKB, BAD and MAPK activities were measured in ischaemic and non-ischaemic lobes at various times after reperfusion. The number of TUNEL-positive cells was significantly decreased after pretreatment with Z-Asp-cmk. In controls, PI3-K and PKB activities and BAD phosphorylation were inhibited in ischaemic liver lobes. The MAPKs (extracellular signal-regulated kinases, c-Jun N-terminal kinase and p38) showed different patterns of activation during IR. PKB activity was not modified by pretreatment with Z-Asp-cmk. Induction of apoptosis during IR liver injury might be triggered by inactivation of the antiapoptotic PI3-K-PKB pathway and activation of the proapoptotic MAPKs. Copyright (c) 2006 British Journal of Surgery Society Ltd. Published by John Wiley & Sons, Ltd.

  7. TRAF6 promotes myogenic differentiation via the TAK1/p38 mitogen-activated protein kinase and Akt pathways.

    Fang Xiao

    Full Text Available p38 mitogen-activated protein kinase (MAPK is an essential kinase involved in myogenic differentiation. Although many substrates of p38 MAPK have been identified, little is known about its upstream activators during myogenic differentiation. TRAF6 is known to function in cytokine signaling during inflammatory responses. However, not much is known about its role in myogenic differentiation and muscle regeneration. We showed here that TRAF6 and its intrinsic ubiquitin E3 ligase activity are required for myogenic differentiation. In mouse myoblasts, knockdown of TRAF6 compromised the p38 MAPK and Akt pathways, while deliberate activation of either pathway rescued the differentiation defect caused by TRAF6 knockdown. TAK1 acted as a key signal transducer downstream of TRAF6 in myogenic differentiation. In vivo, knockdown of TRAF6 in mouse muscles compromised the injury-induced muscle regeneration without impairing macrophage infiltration and myoblast proliferation. Collectively, we demonstrated that TRAF6 promotes myogenic differentiation and muscle regeneration via the TAK1/p38 MAPK and Akt pathways.

  8. Genome-wide identification and expression analysis of the mitogen-activated protein kinase gene family in cassava

    Yan Yan

    2016-08-01

    Full Text Available Mitogen-activated protein kinases (MAPKs play central roles in plant developmental processes, hormone signaling transduction, and responses to abiotic stress. However, no data are currently available about the MAPK family in cassava, an important tropical crop. Herein, 21 MeMAPK genes were identified from cassava. Phylogenetic analysis indicated that MeMAPKs could be classified into four subfamilies. Gene structure analysis demonstrated that the number of introns in MeMAPK genes ranged from 1 to 10, suggesting large variation among cassava MAPK genes. Conserved motif analysis indicated that all MeMAPKs had typical protein kinase domains. Transcriptomic analysis suggested that MeMAPK genes showed differential expression patterns in distinct tissues and in response to drought stress between wild subspecies and cultivated varieties. Interaction networks and co-expression analyses revealed that crucial pathways controlled by MeMAPK networks may be involved in the differential response to drought stress in different accessions of cassava. Expression of nine selected MAPK genes showed that these genes could comprehensively respond to osmotic, salt, cold, oxidative stressors, and abscisic acid (ABA signaling. These findings yield new insights into the transcriptional control of MAPK gene expression, provide an improved understanding of abiotic stress responses and signaling transduction in cassava, and lead to potential applications in the genetic improvement of cassava cultivars.

  9. p38 Mitogen Activated Protein Kinase (MAPK): A New Therapeutic Target for Reducing the Risk of Adverse Pregnancy Outcomes

    Menon, Ramkumar; Papaconstantinou, John

    2016-01-01

    Introduction Spontaneous preterm birth (PTB) and preterm premature rupture of the membranes (pPROM) remain as a major clinical and therapeutic problem for intervention and management. Current strategies, based on our knowledge of pathways of preterm labor, have only been effective, in part, due to major gaps in our existing knowledge of risks and risk specific pathways. Areas covered Recent literature has identified physiologic aging of fetal tissues as a potential mechanistic feature of normal parturition. This process is affected by telomere dependent and p38 mitogen activated protein kinase (MAPK) induced senescence activation. Pregnancy associated risk factors can cause pathologic activation of this pathway that can cause oxidative stress induced p38 MAPK activation leading to senescence and premature aging of fetal tissues. Premature aging is associated with sterile inflammation capable of triggering preterm labor or preterm premature rupture of membranes. Preterm activation of p38MAPK can be considered as a key contributor to adverse pregnancies. Expert Opinion This review considers p38MAPK activation as a potential target for therapeutic interventions to prevent adverse pregnancy outcomes mediated by stress factors. In this review, we propose multiple strategies to prevent p38MAPK activation and its functional effects. PMID:27459026

  10. Mesothelioma Cells Escape Heat Stress by Upregulating Hsp40/Hsp70 Expression via Mitogen-Activated Protein Kinases

    Michael Roth

    2009-01-01

    Full Text Available Therapy with hyperthermal chemotherapy in pleural diffuse malignant mesothelioma had limited benefits for patients. Here we investigated the effect of heat stress on heat shock proteins (HSP, which rescue tumour cells from apoptosis. In human mesothelioma and mesothelial cells heat stress (39–42°C induced the phosphorylation of two mitogen activated kinases (MAPK Erk1/2 and p38, and increased Hsp40, and Hsp70 expression. Mesothelioma cells expressed more Hsp40 and were less sensitive to heat stress compared to mesothelial cells. Inhibition of Erk1/2 MAPK by PD98059 or by Erk1 siRNA down-regulated heat stress-induced Hsp40 and Hsp70 expression and reduced mesothelioma cell survival. Inhibition of p38MAPK by SB203580 or siRNA reduced Hsp40, but not Hsp70, expression and also increased mesothelioma cell death. Thus hyperthermia combined with suppression of p38 MAPK or Hsp40 may represent a novel approach to improve mesothelioma therapy.

  11. Phosphorylation of paxillin via the ERK mitogen-activated protein kinase cascade in EL4 thymoma cells.

    Ku, H; Meier, K E

    2000-04-14

    Intracellular signals can regulate cell adhesion via several mechanisms in a process referred to as "inside-out" signaling. In phorbol ester-sensitive EL4 thymoma cells, phorbol-12-myristate 13-acetate (PMA) induces activation of extracellular signal-regulated kinase (ERK) mitogen-activated protein kinases and promotes cell adhesion. In this study, clonal EL4 cell lines with varying abilities to activate ERKs in response to PMA were used to examine signaling events occurring downstream of ERK activation. Paxillin, a multifunctional docking protein involved in cell adhesion, was phosphorylated on serine/threonine residues in response to PMA treatment. This response was correlated with the extent and time course of ERK activation. PMA-induced phosphorylation of paxillin was inhibited by compounds that block the ERK activation pathway in EL4 cells, primary murine thymocytes, and primary murine splenocytes. Paxillin was phosphorylated in vitro by purified active ERK2. Two-dimensional electrophoresis revealed that PMA treatment generated a complex pattern of phosphorylated paxillin species in intact cells, some of which were generated by ERK-mediated phosphorylation in vitro. An ERK pathway inhibitor interfered with PMA-induced adhesion of sensitive EL4 cells to substrate. These findings describe a novel inside-out signaling pathway by which the ERK cascade may regulate events involved in adhesion.

  12. Promoting resuscitation of viable but nonculturable cells of Vibrio harveyi by a resuscitation-promoting factor-like protein YeaZ.

    Li, Y; Chen, J; Zhao, M; Yang, Z; Yue, L; Zhang, X

    2017-02-01

    To demonstrate the resuscitation-promoting activities of recombinant YeaZ from Vibrio harveyi SF-1. The gene of resuscitation-promoting factor YeaZ was cloned from genomic DNA of V. harveyi SF-1. The gene was expressed in Escherichia coli, and the expressed protein was purified by Ni 2+ -affinity chromatography. A yeaZ mutant was constructed by using the suicide plasmid pNQ705 with homologous recombination. Disruption of yeaZ did not affect cell growth significantly in 2216 E broth at 28°C. The wild-type and mutant viable but nonculturable (VBNC) cells could be resuscitated by temperature upshift method. In addition, the recombinant YeaZ increased the culturable counts from 1·27 × 10 4  CFU per ml and 1·99 × 10 4 CFU per ml to 2·88 × 10 5  CFU per ml and 4·59 × 10 5 CFU per ml, respectively. After the VBNC cells of wild-type and mutant cells were maintained at 4°C for 120 days, no resuscitation was obtained by temperature upshift method, but addition of the recombinant YeaZ promoted the resuscitation of the wild-type and mutant cells, with the culturable cell counts of 1·13 × 10 3 and 1·44 × 10 3 CFU per ml, respectively. Disruption of yeaZ decreased the virulence of V. harveyi in zebrafish. The lethal dose 50% of the yeaZ null mutant was more than 10-fold higher than that of the wild-type cells. The recombinant YeaZ could efficiently promote resuscitation of the wild-type and mutant cells of V. harveyi from VBNC to culturable state. The protein also promoted resuscitation of the VBNC wild-type and mutant cells, which were maintained at 4°C for 120 days and not recovered by temperature upshift method. Disruption of yeaZ decreased the virulence of V. harveyi in zebrafish. Here, we show clear evidence of a resuscitation-promoting factor YeaZ of V. harveyi and the roles in resuscitation of the VBNC cells and its pathogenicity. © 2016 The Society for Applied Microbiology.

  13. Reduced response of splenocytes after mitogen-stimulation in the prion protein (PrP) gene-deficient mouse: PrPLP/Doppel production and cerebral degeneration

    Kim, Chi-Kyeong; Hirose, Yuko; Sakudo, Akikazu; Takeyama, Natsumi; Kang, Chung-Boo; Taniuchi, Yojiro; Matsumoto, Yoshitsugu; Itohara, Shigeyoshi; Sakaguchi, Suehiro; Onodera, Takashi

    2007-01-01

    Splenocytes of wild-type (Prnp +/+ ) and prion protein gene-deficient (Prnp -/- ) mice were treated with various activation stimuli such as T cell mitogen concanavalin A (ConA), phorbol 12-myristate 13-acetate (PMA) + ionomycin (Io), or B cell mitogen lipopolysaccharide (LPS). Cellular prion protein (PrP C ) expression was enhanced following ConA stimulation, but not PMA + Io or LPS in Prnp +/+ splenocytes. Rikn Prnp -/- splenocytes elicited lower cell proliferations than Prnp +/+ or Zrch I Prnp -/- splenocytes after LPS stimulation and showed sporadic nerve cells in the cerebral cortex and deeper structure. Around the degenerated nerve cells, mild vacuolation in the neuropil was observed. This neural alteration correlated well to the suppressed response of B cells in the spleen. The finding that discrete lesions within the central nervous systems induced marked modulation of immune function probably indicates the existence of a delicately balanced neural-endocrine network by PrP C and PrPLP/Doppel

  14. Optimized choice of method for determining proliferation response of peripheral lymphocytes to mitogens in low dose irradiation with cyclotron fast neutrons

    Refka, Z.; Svec, M.; Aganov, P.; Svoboda, V.; Podzimek, F.

    1989-01-01

    Heparinized venous blood sampled from seven donors was irradiated with doses of 0.1; 0.25; 0.5; 1.0; 2.0 and 3.0 Gy of fast neutrons of a mean energy of 7.6 MeV using the U 120 M isochronous cyclotron. A non-irradiated control sample was also prepared. A lymphoblastic transformation test was conducted with both the intact and irradiated samples. The samples were cultivated in the RPMI-1640 medium with and without a mitogen addition, this in five time variants, viz., for 48, 72, 90, 96 and 120 hours. The proliferation was monitored of lymphocytes stimulated with mitogens PHA, CON-A and PWM in dependence on the time of cultivation and on the radiation dose. The dose dependent relative response was also studied of the irradiated lymphocytes. (E.J.). 8 figs., 1 tab., 18 refs

  15. Evidence of a New Role for the High-Osmolarity Glycerol Mitogen-Activated Protein Kinase Pathway in Yeast: Regulating Adaptation to Citric Acid Stress†

    Lawrence, Clare L.; Botting, Catherine H.; Antrobus, Robin; Coote, Peter J.

    2004-01-01

    Screening the Saccharomyces cerevisiae disruptome, profiling transcripts, and determining changes in protein expression have identified an important new role for the high-osmolarity glycerol (HOG) mitogen-activated protein kinase (MAPK) pathway in the regulation of adaptation to citric acid stress. Deletion of HOG1, SSK1, PBS2, PTC2, PTP2, and PTP3 resulted in sensitivity to citric acid. Furthermore, citric acid resulted in the dual phosphorylation, and thus activation, of Hog1p. Despite mino...

  16. Hypoxia-Induced Mitogenic Factor (HIMF/FIZZ1/RELM?) Recruits Bone Marrow-Derived Cells to the Murine Pulmonary Vasculature

    Angelini, Daniel J.; Su, Qingning; Kolosova, Irina A.; Fan, Chunling; Skinner, John T.; Yamaji-Kegan, Kazuyo; Collector, Michael; Sharkis, Saul J.; Johns, Roger A.

    2010-01-01

    Background Pulmonary hypertension (PH) is a disease of multiple etiologies with several common pathological features, including inflammation and pulmonary vascular remodeling. Recent evidence has suggested a potential role for the recruitment of bone marrow-derived (BMD) progenitor cells to this remodeling process. We recently demonstrated that hypoxia-induced mitogenic factor (HIMF/FIZZ1/RELM?) is chemotactic to murine bone marrow cells in vitro and involved in pulmonary vascular remodeling ...

  17. Growth properties and growth factor responsiveness in skin fibroblasts from centenarians.

    Tesco, G; Vergelli, M; Grassilli, E; Salomoni, P; Bellesia, E; Sikora, E; Radziszewska, E; Barbieri, D; Latorraca, S; Fagiolo, U; Santacaterina, S; Amaducci, L; Tiozzo, R; Franceschi, C; Sorbi, S

    1998-03-27

    Human fibroblast cultures, which have a finite replicative lifespan in vitro, are the most widely used model for the study of senescence at the cellular level. An inverse relationship between replicative capability and donor age has been reported in human fibroblast strains. We studied the growth capacity of fibroblast primary cultures derived from people whose lifespan was as closer as possible to the expected maximum human lifespan, i.e. people over one hundred. Our data suggest that outgrowth of fibroblasts from biopsies, growth kinetics at different population doubling levels, capability to respond to a classical mitogenic stimulus (such as 20% serum) and a variety of growth factors, were remarkably similar in fibroblasts from centenarians and young controls. On the whole, our data challenge the tenet of a simple and strict relationship between in vivo aging and in vitro proliferative capability of human fibroblasts, at least at the individual level.

  18. Effects of metal ions on cyprinid fish immune response: In vitro effects of Zn2+ and Mn2+ on the mitogenic response of carp pronephros lymphocytes

    Ghanmi, Z.; Rouabhia, M.; Othmane, O.; Deschaux, P.A.

    1989-01-01

    Lymphocytes from the pronephros of carp (Cyprinus carpio L) have been subjected to transformation by mitogens, concanavalin A (Con A), phytohemagglutinin (PHA), and lipopolysaccharides (LPS), with Zn or Mn at varying concentrations. Addition of Zn 2+ (10(-7) to 10(-3) M) to mitogen-stimulated T and B cells enhanced [ 3 H]thymidine incorporation. Addition of 10(-5) M Zn 2+ inhibited the response to Con A, PHA, and LPS. At this concentration, Zn was toxic. Addition of Mn2+ (10(-7) to 10(-3) M) to mitogen-stimulated lymphocytes enhanced [ 3 H]thymidine incorporation. This effect was observed with Con A- and PHA-stimulated lymphocytes, but not with LPS-stimulated lymphocytes. In contrast, addition of 10(-1) M Mn 2+ to lymphocyte cultures exerted an inhibitor on the response to Con A or to PHA, while the response to LPS was unaffected. Addition of 10(-1) M Mn 2+ to Con A- or PHA-stimulated cultures at different times after initiation of stimulation indicated that Mn 2+ was inhibitory only when it was added before the first 16 hr of cultures. The inhibition induced by 10(-1) M Mn2+ could be reversed by adding 2 mM CaCl 2 to the culture

  19. The down-regulation of the mitogenic fibrinogen receptor (MFR) in serum-containing medium does not occur in defined medium.

    Levesque, J P; Hatzfeld, A; Domart, I; Hatzfeld, J

    1990-02-01

    Normal human hemopoietic cells such as early bone marrow progenitors, or lymphoma-derived cell lines such as Raji or JM cells, possess a low-affinity receptor specific for fibrinogen. This receptor triggers a mitogenic effect. It differs from the glycoprotein IIb-IIIa which is involved in fibrinogen-induced platelet aggregation. We demonstrate here that this mitogenic fibrinogen receptor (MFR) can be internalized or reexpressed, depending on culture conditions. Internalization was temperature-dependent. At 37 degrees C in the presence of cycloheximide or actinomycin D, the half-life of cell surface MFRs was 2 h, independent of receptor occupancy. Binding of fibrinogen to the MFR resulted in a down-regulation which was fibrinogen dose-dependent. This occurred in serum-supplemented medium but not in defined medium supplemented with fatty acids. Reexpression of MFRs could be induced in 28 to 42 h by serum removal. The down-regulation of mitogenic receptors in plasma or serum could explain why normal cells do not proliferate in the peripheral blood.

  20. Endocrine Regulation of Compensatory Growth in Fish

    Eugene T. Won

    2013-07-01

    Full Text Available Compensatory growth (CG is a period of accelerated growth that occurs following the alleviation of growth-stunting conditions during which an organism can make up for lost growth opportunity and potentially catch-up in size with non-stunted cohorts. Fish show a particularly robust capacity for the response and have been the focus of numerous studies that demonstrate their ability to compensate for periods of fasting once food is made available again. Compensatory growth is characterized by an elevated growth rate resulting from enhanced feed intake, mitogen production and feed conversion efficiency. Because little is known about the underlying mechanisms that drive the response, this review describes the sequential endocrine adaptations that lead to CG; namely during the precedent catabolic phase (fasting that taps endogenous energy reserves, and the following hyperanabolic phase (refeeding when accelerated growth occurs. In order to elicit a CG response, endogenous energy reserves must first be moderately depleted, which alters endocrine profiles that enhance appetite and growth potential. During this catabolic phase, elevated ghrelin and growth hormone (GH production increase appetite and protein-sparing lipolysis, while insulin-like growth factors (IGFs are suppressed, primarily due to hepatic GH resistance. During refeeding, temporal hyperphagia provides an influx of energy and metabolic substrates that are then allocated to somatic growth by resumed IGF signaling. Under the right conditions, refeeding results in hyperanabolism and a steepened growth trajectory relative to constantly fed controls. The response wanes as energy reserves are re-accumulated and homeostasis is restored. We ascribe possible roles for select appetite and growth-regulatory hormones in the context of these catabolic and hyperanabolic phases of the CG response in teleosts, with emphasis on GH, IGFs, cortisol, somatostatin, neuropeptide Y, ghrelin and leptin.

  1. Runx expression is mitogenic and mutually linked to Wnt activity in blastula-stage sea urchin embryos.

    Anthony J Robertson

    Full Text Available The Runt homology domain (Runx defines a metazoan family of sequence-specific transcriptional regulatory proteins that are critical for animal development and causally associated with a variety of mammalian cancers. The sea urchin Runx gene SpRunt-1 is expressed throughout the blastula stage embryo, and is required globally during embryogenesis for cell survival and differentiation.Depletion of SpRunt-1 by morpholino antisense-mediated knockdown causes a blastula stage deficit in cell proliferation, as shown by bromodeoxyuridine (BrdU incorporation and direct cell counts. Reverse transcription coupled polymerase chain reaction (RT-PCR studies show that the cell proliferation deficit is presaged by a deficit in the expression of several zygotic wnt genes, including wnt8, a key regulator of endomesoderm development. In addition, SpRunt-1-depleted blastulae underexpress cyclinD, an effector of mitogenic Wnt signaling. Blastula stage cell proliferation is also impeded by knockdown of either wnt8 or cyclinD. Chromatin immunoprecipitation (ChIP indicates that Runx target sites within 5' sequences flanking cyclinD, wnt6 and wnt8 are directly bound by SpRunt-1 protein at late blastula stage. Furthermore, experiments using a green fluorescent protein (GFP reporter transgene show that the blastula-stage operation of a cis-regulatory module previously shown to be required for wnt8 expression (Minokawa et al., Dev. Biol. 288: 545-558, 2005 is dependent on its direct sequence-specific interaction with SpRunt-1. Finally, inhibitor studies and immunoblot analysis show that SpRunt-1 protein levels are negatively regulated by glycogen synthase kinase (GSK-3.These results suggest that Runx expression and Wnt signaling are mutually linked in a feedback circuit that controls cell proliferation during development.

  2. Selective Expansion of Memory CD4+ T cells By Mitogenic Human CD28 Generates Inflammatory Cytokines and Regulatory T cells

    Singh, Manisha; Basu, Sreemanti; Camell, Christina; Couturier, Jacob; Nudelman, Rodolfo J.; Medina, Miguel A.; Rodgers, John R.; Lewis, Dorothy E.

    2009-01-01

    Co-stimulatory signals are important for development of effector and regulatory T cells. In this case, CD28 signaling is usually considered inert in the absence of signaling through the TCR. By contrast, mitogenic rat CD28 mAbs reportedly expand regulatory T cells without TCR stimulation. We found that a commercially available human CD28 mAb (ANC28) stimulated PBMCs without TCR co-ligation or cross-linking; ANC28 selectively expanded CD4+CD25+FoxP3−(T effector) and CD4+CD25+FoxP3+ (Treg) cells. ANC28 stimulated the CD45RO+ CD4+ (memory) population whereas CD45RA+CD4+ (naïve) cells did not respond. ANC28 also induced inflammatory cytokines. Treg induced by ANC28 retain the Treg phenotype longer than did co-stimulated Treg. Treg induced by ANC28 suppressed CD25− T cells through a contact-dependent mechanism. Purity influenced the response of CD4+CD25+ cells because bead-purified CD4+CD25+ cells (85–90% pure) responded strongly to ANC28, whereas 98% pure FACS-sorted CD4+CD25 bright (T-reg) did not respond. Purified CD4+CD25int cells responded similarly to the bead-purified CD4+CD25+ cells. Thus, pre-activated CD4+ T cells (CD25int) respond to ANC28 rather than Treg (CD25bright). The ability of ANC28 to expand both effectors producing inflammatory cytokines as well as suppressive regulatory T cells might be useful for ex vivo expansion of therapeutic T cells. PMID:18446791

  3. Involvement of a novel p38 mitogen-activated protein kinase in larval metamorphosis of the polychaete Hydroides elegans (Haswell)

    Wang, Hao

    2010-04-19

    Hydroides elegans is a common marine fouling organism in most tropical and subtropical waters. The life cycle of H. elegans includes a planktonic larval stage in which swimming larvae normally take 5 days to attain competency to settle. Larval metamorphosis marks the beginning of its benthic life; however, the endogenous molecular mechanisms that regulate metamorphosis remain largely unknown. In this study, a PCR-based suppressive subtractive hybridization (SSH) library was constructed to screen the genes expressed in competent larvae but not in precompetent larvae. Among the transcripts isolated from the library, 21 significantly matched sequences in the GenBank. Many of these isolated transcripts have putative roles in the reactive oxygen species (ROS) signal transduction pathway or in response to ROS stress. A putative novel p38 mitogen-activated protein kinase (MAPK), which was also isolated with SSH screen, was then cloned and characterized. The MAPK inhibitors assay showed that both p38 MAPK inhibitors SB202190 and SB203580 effectively inhibited the biofilm-induced metamorphosis of H. elegans. A cell stressors assay showed that H2O2 effectively induced larval metamorphosis of H. elegans, but the inductivity of H2O2 was also inhibited by both SB inhibitors. The catalase assay showed that the catalase could effetely inhibit H. elegans larvae from responding to inductive biofilm. These results showed that the p38 MAPK-dependent pathway plays critical role in controlling larval metamorphosis of the marine polychaete H. elegans, and the reactive oxygen radicals produced by biofilm could be the cue inducing larval metamorphosis. © 2010 Wiley-Liss, Inc.

  4. Mitogen-activated protein kinase phosphatase-1 modulates regional effects of injurious mechanical ventilation in rodent lungs.

    Park, Moo Suk; He, Qianbin; Edwards, Michael G; Sergew, Amen; Riches, David W H; Albert, Richard K; Douglas, Ivor S

    2012-07-01

    Mechanical ventilation induces heterogeneous lung injury by mitogen-activated protein kinase (MAPK) and nuclear factor-κB. Mechanisms regulating regional injury and protective effects of prone positioning are unclear. To determine the key regulators of the lung regional protective effects of prone positioning in rodent lungs exposed to injurious ventilation. Adult rats were ventilated with high (18 ml/kg, positive end-expiratory pressure [PEEP] 0) or low Vt (6 ml/kg; PEEP 3 cm H(2)O; 3 h) in supine or prone position. Dorsal-caudal lung mRNA was analyzed by microarray and MAPK phosphatases (MKP)-1 quantitative polymerase chain reaction. MKP-1(-/-) or wild-type mice were ventilated with very high (24 ml/kg; PEEP 0) or low Vt (6-7 ml/kg; PEEP 3 cm H(2)O). The MKP-1 regulator PG490-88 (MRx-108; 0.75 mg/kg) or phosphate-buffered saline was administered preventilation. Injury was assessed by lung mechanics, bronchioalveolar lavage cell counts, protein content, and lung injury scoring. Immunoblotting for MKP-1, and IκBα and cytokine ELISAs were performed on lung lysates. Prone positioning was protective against injurious ventilation in rats. Expression profiling demonstrated MKP-1 20-fold higher in rats ventilated prone rather than supine and regional reduction in p38 and c-jun N-terminal kinase activation. MKP-1(-/-) mice experienced amplified injury. PG490-88 improved static lung compliance and injury scores, reduced bronchioalveolar lavage cell counts and cytokine levels, and induced MKP-1 and IκBα. Injurious ventilation induces MAPK in an MKP-1-dependent fashion. Prone positioning is protective and induces MKP-1. PG490-88 induced MKP-1 and was protective against high Vt in a nuclear factor-κB-dependent manner. MKP-1 is a potential target for modulating regional effects of injurious ventilation.

  5. Protein Kinase Mitogen-activated Protein Kinase Kinase Kinase Kinase 4 (MAP4K4) Promotes Obesity-induced Hyperinsulinemia.

    Roth Flach, Rachel J; Danai, Laura V; DiStefano, Marina T; Kelly, Mark; Menendez, Lorena Garcia; Jurczyk, Agata; Sharma, Rohit B; Jung, Dae Young; Kim, Jong Hun; Kim, Jason K; Bortell, Rita; Alonso, Laura C; Czech, Michael P

    2016-07-29

    Previous studies revealed a paradox whereby mitogen-activated protein kinase kinase kinase kinase 4 (Map4k4) acted as a negative regulator of insulin sensitivity in chronically obese mice, yet systemic deletion of Map4k4 did not improve glucose tolerance. Here, we report markedly reduced glucose-responsive plasma insulin and C-peptide levels in whole body Map4k4-depleted mice (M4K4 iKO) as well as an impaired first phase of insulin secretion from islets derived from M4K4 iKO mice ex vivo After long-term high fat diet (HFD), M4K4 iKO mice pancreata also displayed reduced β cell mass, fewer proliferating β cells and reduced islet-specific gene mRNA expression compared with controls, although insulin content was normal. Interestingly, the reduced plasma insulin in M4K4 iKO mice exposed to chronic (16 weeks) HFD was not observed in response to acute HFD challenge or short term treatment with the insulin receptor antagonist S961. Furthermore, the improved insulin sensitivity in obese M4K4 iKO mice was abrogated by high exogenous insulin over the course of a euglycemic clamp study, indicating that hypoinsulinemia promotes insulin sensitivity in chronically obese M4K4 iKO mice. These results demonstrate that protein kinase Map4k4 drives obesity-induced hyperinsulinemia and insulin resistance in part by promoting insulin secretion from β cells in mice. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  6. Mitogen activated protein kinase phosphatase-1 prevents the development of tactile sensitivity in a rodent model of neuropathic pain

    Ndong Christian

    2012-04-01

    Full Text Available Abstract Background Neuropathic pain due to nerve injury is one of the most difficult types of pain to treat. Following peripheral nerve injury, neuronal and glial plastic changes contribute to central sensitization and perpetuation of mechanical hypersensitivity in rodents. The mitogen activated protein kinase (MAPK family is pivotal in this spinal cord plasticity. MAPK phosphatases (MKPs limit inflammatory processes by dephosphorylating MAPKs. For example, MKP-1 preferentially dephosphorylates p-p38. Since spinal p-p38 is pivotal for the development of chronic hypersensitivity in rodent models of pain, and p-p38 inhibitors have shown clinical potential in acute and chronic pain patients, we hypothesize that induction of spinal MKP-1 will prevent the development of peripheral nerve-injury-induced hypersensitivity and p-p38 overexpression. Results We cloned rat spinal cord MKP-1 and optimize MKP-1 cDNA in vitro using transfections to BV-2 cells. We observed that in vitro overexpression of MKP-1 blocked lipopolysaccharide-induced phosphorylation of p38 (and other MAPKs as well as release of pro-algesic effectors (i.e., cytokines, chemokines, nitric oxide. Using this cDNA MKP-1 and a non-viral, in vivo nanoparticle transfection approach, we found that spinal cord overexpression of MKP-1 prevented development of peripheral nerve-injury-induced tactile hypersensitivity and reduced pro-inflammatory cytokines and chemokines and the phosphorylated form of p38. Conclusions Our results indicate that MKP-1, the natural regulator of p-p38, mediates resolution of the spinal cord pro-inflammatory milieu induced by peripheral nerve injury, resulting in prevention of chronic mechanical hypersensitivity. We propose that MKP-1 is a potential therapeutic target for pain treatment or prevention.

  7. Toward a comprehensive phylogenetic reconstruction of the evolutionary history of mitogen-activated protein kinases in the plant kingdom.

    Janitza, Philipp; Ullrich, Kristian Karsten; Quint, Marcel

    2012-01-01

    The mitogen-activated protein kinase (MAPK) pathway is a three-tier signaling cascade that transmits cellular information from the plasma membrane to the cytoplasm where it triggers downstream responses. The MAPKs represent the last step in this cascade and are activated when both tyrosine and threonine residues in a conserved TxY motif are phosphorylated by MAPK kinases, which in turn are themselves activated by phosphorylation by MAPK kinase kinases. To understand the molecular evolution of MAPKs in the plant kingdom, we systematically conducted a Hidden-Markov-Model based screen to identify MAPKs in 13 completely sequenced plant genomes. In this analysis, we included green algae, bryophytes, lycophytes, and several mono- and eudicotyledonous species covering >800 million years of evolution. The phylogenetic relationships of the 204 identified MAPKs based on Bayesian inference facilitated the retraction of the sequence of emergence of the four major clades that are characterized by the presence of a TDY or TEY-A/TEY-B/TEY-C type kinase activation loop. We present evidence that after the split of TDY- and TEY-type MAPKs, initially the TEY-C clade emerged. This was followed by the TEY-B clade in early land plants until the TEY-A clade finally emerged in flowering plants. In addition to these well characterized clades, we identified another highly conserved clade of 45 MAPK-likes, members of which were previously described as Mak-homologous kinases. In agreement with their essential functions, molecular population genetic analysis of MAPK genes in Arabidopsis thaliana accessions reveal that purifying selection drove the evolution of the MAPK family, implying strong functional constraints on MAPK genes. Closely related MAPKs most likely subfunctionalized, a process in which differential transcriptional regulation of duplicates may be involved.

  8. Towards a comprehensive phylogenetic reconstruction of the evolutionary history of mitogen-activated protein kinases in the plant kingdom

    Philipp eJanitza

    2012-12-01

    Full Text Available The mitogen-activated protein kinase (MAPK pathway is a three-tier signaling cascade that transmits cellular information from the plasma membrane to the cytoplasm where it triggers downstream responses. The MAPKs represent the last step in this cascade and are activated when both tyrosine and threonine residues in a conserved TxY motif are phosphorylated by MAPK kinases, which in turn are themselves activated by phosphorylation by MAPK kinase kinases. To understand the molecular evolution of MAPKs in the plant kingdom, we systematically conducted a Hidden-Markov-Model based screen to identify MAPKs in 13 completely sequenced plant genomes. In this analysis, we included green algae, bryophytes, lycophytes, and several mono- and dicotyledonous species covering >800 million years of evolution. The phylogenetic relationships of the 204 identified MAPKs based on Bayesian inference facilitated the retraction of the sequence of emergence of the four major clades that are characterized by the presence of a TDY or TEY-A/TEY-B/TEY-C type kinase activation loop. We present evidence that after the split of TDY- and TEY-type MAPKs, initially the TEY-C clade emerged. This was followed by the TEY-B clade in early land plants until the TEY-A clade finally emerged in flowering plants. In addition to these well characterized clades, we identified another highly conserved clade of 45 MAPK-likes, members of which were previously described as MHKs. In agreement with their essential functions, molecular population genetic analysis of MAPK genes in Arabidopsis thaliana accessions reveal that purifying selection drove the evolution of the MAPK family, implying strong functional constraints on MAPK genes. Closely related MAPKs most likely subfunctionalized, a process in which differential transcriptional regulation of duplicates may be involved.

  9. Involvement of p38 mitogen-activated protein kinase in acquired gemcitabine-resistant human urothelial carcinoma sublines

    Yu-Ting Kao

    2014-07-01

    Full Text Available Resistance to chemotherapeutic drugs is one of the major challenges in the treatment of cancer. A better understanding of how resistance arises and what molecular alterations correlate with resistance is the key to developing novel effective therapeutic strategies. To investigate the underlying mechanisms of gemcitabine (Gem resistance and provide possible therapeutic options, three Gem-resistant urothelial carcinoma sublines were established (NG0.6, NG0.8, and NG1.0. These cells were cross-resistant to arabinofuranosyl cytidine and cisplatin, but sensitive to 5-fluorouracil. The resistant cells expressed lower values of [hENT1 × dCK/RRM1 × RRM2] mRNA ratio. Two adenosine triphosphate-binding cassette proteins ABCD1 as well as multidrug resistance protein 1 were elevated. Moreover, cyclin D1, cyclin-dependent kinases 2 and 4 were upregulated, whereas extracellular signal-regulated kinase 1/2 and p38 mitogen-activated protein kinase (MAPK activity were repressed significantly. Administration of p38 MAPK inhibitor significantly reduced the Gem sensitivity in NTUB1 cells, whereas that of an extracellular signal-regulated kinase MAPK inhibitor did not. Furthermore, the Gem-resistant sublines also exhibited higher migration ability. Forced expression of p38 MAPK impaired the cell migration activity and augmented Gem sensitivity in NG1.0 cells. Taken together, these results demonstrate that complex mechanisms were merged in acquiring Gem resistance and provide information that can be important for developing therapeutic targets for treating Gem-resistant tumors.

  10. Brominated flame retardants, tetrabromobisphenol A and hexabromocyclododecane, activate mitogen-activated protein kinases (MAPKs) in human natural killer cells.

    Cato, Anita; Celada, Lindsay; Kibakaya, Esther Caroline; Simmons, Nadia; Whalen, Margaret M

    2014-12-01

    Natural killer (NK) cells provide a vital surveillance against virally infected cells, tumor cells, and antibody-coated cells through the release of cytolytic mediators and gamma interferon (IFN-γ). Hexabromocyclododecane (HBCD) is a brominated flame retardant used primarily in expanded (EPS) and extruded (XPS) polystyrene foams for thermal insulation in the building and construction industry. Tetrabromobisphenol A (TBBPA) is used both as a reactive and an additive flame retardant in a variety of materials. HBCD and TBBPA contaminate the environment and are found in human blood samples. In previous studies, we have shown that other environmental contaminants, such as the dibutyltin (DBT) and tributyltin (TBT), decrease NK lytic function by activating mitogen-activated protein kinases (MAPKs) in the NK cells. HBCD and TBBPA also interfere with NK cell(s) lytic function. The current study evaluates whether HBCD and/or TBBPA have the capacity to activate MAPKs and MAPK kinases (MAP2Ks). The effects of concentrations of HBCD and TBBPA that inhibited lytic function on the phosphorylation state and total levels of the MAPKs (p44/42, p38, and JNK) and the phosphorylation and total levels of the MAP2Ks (MEK1/2 and MKK3/6) were examined. Results indicate that exposure of human NK cells to 10-0.5 μM HBCD or TBBPA activate MAPKs and MAP2Ks. This HBCD and TBBPA-induced activation of MAPKs may leave them unavailable for activation by virally infected or tumor target cells and thus contributes to the observed decreases in lytic function seen in NK cells exposed to HBCD and TBBPA.

  11. T cell activation and proliferation following acute exercise in human subjects is altered by storage conditions and mitogen selection.

    Siedlik, Jacob A; Deckert, Jake A; Benedict, Stephen H; Bhatta, Anuja; Dunbar, Amanda J; Vardiman, John P; Gallagher, Philip M

    2017-07-01

    Recent work investigating exercise induced changes in immunocompetence suggests that some of the ambiguity in the literature is resultant from different cell isolation protocols and mitogen selection. To understand this effect, we compared post-exercise measures of T cell activation and proliferation using two different stimulation methods (costimulation through CD28 or stimulation with phytohaemagglutinin [PHA]). Further, we investigated whether exercise induced changes are maintained when T cell isolation from whole blood is delayed overnight in either a room temperature or chilled (4°C) environment. As expected, an increased proliferation response was observed post-exercise in T cells isolated from whole blood of previously trained individuals immediately after blood collection. Also, cells stimulated with PHA after resting overnight in whole blood were not adversely impacted by the storage conditions. In contrast, allowing cells to rest overnight in whole blood prior to stimulation through CD28, lessened the proliferation observed by cells following exercise rendering both the room temperature and chilled samples closer to the results seen in the control condition. Changes in early markers of activation (CD25), followed a similar pattern, with activation in PHA stimulated cells remaining fairly robust after overnight storage; whereas cell activation following stimulation through CD3+CD28 was disproportionately decreased by the influence of overnight storage. These findings indicate that decisions regarding cell stimulation methods need to be paired with the timeline for T cell isolation from whole blood. These considerations will be especially important for field based studies of immunocompetence where there is a delay in getting whole blood samples to a lab for processing as well as clinical applications where a failure to isolate T cells in a timely manner may result in loss of the response of interest. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. p38 mitogen-activated protein kinase mediates IL-8 induction by the ribotoxin deoxynivalenol in human monocytes

    Islam, Zahidul; Gray, Jennifer S.; Pestka, James J.

    2006-01-01

    The effects of the ribotoxic trichothecene deoxynivalenol (DON) on mitogen-activated protein kinase (MAPK)-mediated IL-8 expression were investigated in cloned human monocytes and peripheral blood mononuclear cells (PBMC). DON (250 to 1000 ng/ml) induced both IL-8 mRNA and IL-8 heteronuclear RNA (hnRNA), an indicator of IL-8 transcription, in the human U937 monocytic cell line in a concentration-dependent manner. Expression of IL-8 hnRNA, mRNA and protein correlated with p38 phosphorylation and was completely abrogated by the p38 MAPK inhibitor SB203580. DON at 500 ng/ml similarly induced p38-dependent IL-8 protein and mRNA expression in PBMC cultures from healthy volunteers. Significantly increased IL-6 and IL-1β intracellular protein and mRNA expression was also observed in PBMC treated with DON (500 ng/ml) which were also partially p38-dependent. Flow cytometry of PBMC revealed that DON-induced p38 phosphorylation varied among individuals relative to both threshold toxin concentrations (25-100 ng/ml) and relative increases in percentages of phospho-p38 + cells. DON-induced p38 activation occurred exclusively in the CD14 + monocyte population. DON was devoid of agonist activity for human Toll-like receptors 2, 3, 4, 5, 7, 8 and 9. However, two other ribotoxins, emetine and anisomycin, induced p38 phosphorylation in PBMC similarly to DON. Taken together, these data suggest that (1) p38 activation was required for induction of IL-8 and proinflammatory gene expression in the monocyte and (2) DON induced p38 activation in human monocytes via the ribotoxic stress response

  13. Delayed growth

    ... Slow rate of growth; Retarded growth and development; Growth delay Images Toddler development References Cooke DW, Divall SA, Radovick S. Normal and aberrant growth in children. In: Melmed S, Polonsky KS, Larsen PR, ...

  14. Identification and purification of truncated insulin-like growth factor I from porcine uterus. Evidence for high biological potency

    Ogasawara, M.; Karey, K.P.; Marquardt, H.; Sirbasku, D.A.

    1989-01-01

    The authors report the completion of the purification of uterine-derived growth factors (UDGF) described previously by this laboratory. During isolation, the mitogenic activity was monitored by using the human MCF-7 breast cancer cells in serum-free Ham's F12 and Dulbecco's modified Eagle's medium (1:1, v/v) containing 15 mM 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid, 200 μg/mL bovine serum albumin, and 10 μg/mL human transferrin. This medium sustained growth for several days in response to a single addition of growth factor. The mitogens were shown by protein microsequencing to be DES 1 → 3 to DES 1 → 6 forms of insulin-like growth factor I (truncated IGF-I). An M r estimated by 125 I labeling, urea-sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and autoradiography was consistent with a DES 1 → 3(4) N α truncation. Immunoadsorption and radioimmunoassay confirmed immunological properties equivalent to IGF-I. Radioreceptor assays showed truncated IGF-I was functionally equivalent to recombinant IGF-I. They conclude that the major acid-stable low-M r mitogenic activities isolated from uterus are very potent forms of truncated IGF-I capable of stimulating growth of epithelial and mesenchymal cells

  15. Insulin-like growth factor II: complexity of biosynthesis and receptor binding

    Gammeltoft, S; Christiansen, Jan; Nielsen, F C

    1991-01-01

    Insulin-like growth factor II (IGF-II) belongs to the insulin family of peptides and acts as a growth factor in many fetal tissues and tumors. The gene expression of IGF-II is initiated at three different promoters which gives rise to multiple transcripts. In a human rhabdomyosarcoma cell line......, Man-6-P induces cellular responses. We have studied rat brain neuronal precursor cells where Man-6-P acted as a mitogen suggesting that phosphomannosylated proteins may act as growth factors via the Man-6-P/IGF-II receptor. In conclusion, the gene expression and mechanism of action of IGF-II is very...

  16. Insulin-like growth factor family and combined antisense approach in therapy of lung carcinoma.

    Pavelić, Jasminka; Pavelić, Ljubomir; Karadza, Jerolim; Krizanac, Simun; Unesić, Josip; Spaventi, Sime; Pavelić, Kresimir

    2002-01-01

    BACKGROUND: Perturbation in a level of any peptide from insulin-like growth factor (IGF) family (ligands, receptors, and binding proteins) seems to be implicated in lung cancer formation; IGF ligands and IGF-I receptor through their mitogenic and anti-apoptotic action, and the mannose 6-phosphate/insulin-like growth factor II receptor (M6-P/IGF-IIR) possibly as a tumor suppressor. MATERIALS AND METHODS: To determine the identity, role, and mutual relationship of IGFs in lung cancer growth and...

  17. Lysophosphatidylcholine Promotes Phagosome Maturation and Regulates Inflammatory Mediator Production Through the Protein Kinase A–Phosphatidylinositol 3 Kinase–p38 Mitogen-Activated Protein Kinase Signaling Pathway During Mycobacterium tuberculosis Infection in Mouse Macrophages

    Hyo-Ji Lee

    2018-04-01

    Full Text Available Tuberculosis is caused by the infectious agent Mycobacterium tuberculosis (Mtb. Mtb has various survival strategies, including blockade of phagosome maturation and inhibition of antigen presentation. Lysophosphatidylcholine (LPC is a major phospholipid component of oxidized low-density lipoprotein and is involved in various cellular responses, such as activation of second messengers and bactericidal activity in neutrophils. In this study, macrophages were infected with a low infectious dose of Mtb and treated with LPC to investigate the bactericidal activity of LPC against Mtb. In macrophages infected with Mtb strain, H37Ra or H37Rv, LPC suppressed bacterial growth; however, this effect was suppressed in bone marrow-derived macrophages (BMDMs isolated from G2A (a G protein-coupled receptor involved in some LPC actions knockout mice. LPC also promoted phagosome maturation via phosphatidylinositol 3 kinase (PI3K–p38 mitogen-activated protein kinase (MAPK-mediated reactive oxygen species production and intracellular Ca2+ release during Mtb infection. In addition, LPC induced increased levels of intracellular cyclic adenosine monophosphate (cAMP and phosphorylated glycogen synthase kinase 3 beta (GSK3β in Mtb-infected macrophages. Protein kinase A (PKA-induced phosphorylation of GSK3β suppressed activation of NF-κB in LPC-treated macrophages during Mtb infection, leading to decreased secretion of pro-inflammatory cytokines and increased secretion of anti-inflammatory cytokines. These results suggest that LPC can effectively control Mtb growth by promoting phagosome maturation via cAMP-induced activation of the PKA–PI3K–p38 MAPK pathway. Moreover, LPC can regulate excessive production of pro-inflammatory cytokines associated with bacterial infection of macrophages.

  18. The competencial factor like an engine venture

    Angel Olaz Capitán

    2016-06-01

    Full Text Available The purpose of this paper is to establish the connections in the triad woman, entrepreneurship and competences from a holistic perspective in order to mean what are the key competences and how they contribute to the development of entrepreneurship from a gender perspective. The concept of qualifications will be analyzed as a substrate of the competences issues for articulating an explicative model that allows its objectification.

  19. The yeast mitogen-activated protein kinase Slt2 is involved in the cellular response to genotoxic stress

    Soriano-Carot María

    2012-02-01

    Full Text Available Abstract Background The maintenance of genomic integrity is essential for cell viability. Complex signalling pathways (DNA integrity checkpoints mediate the response to genotoxic stresses. Identifying new functions involved in the cellular response to DNA-damage is crucial. The Saccharomyces cerevisiae SLT2 gene encodes a member of the mitogen-activated protein kinase (MAPK cascade whose main function is the maintenance of the cell wall integrity. However, different observations suggest that SLT2 may also have a role related to DNA metabolism. Results This work consisted in a comprehensive study to connect the Slt2 protein to genome integrity maintenance in response to genotoxic stresses. The slt2 mutant strain was hypersensitive to a variety of genotoxic treatments, including incubation with hydroxyurea (HU, methylmetanosulfonate (MMS, phleomycin or UV irradiation. Furthermore, Slt2 was activated by all these treatments, which suggests that Slt2 plays a central role in the cellular response to genotoxic stresses. Activation of Slt2 was not dependent on the DNA integrity checkpoint. For MMS and UV, Slt2 activation required progression through the cell cycle. In contrast, HU also activated Slt2 in nocodazol-arrested cells, which suggests that Slt2 may respond to dNTP pools alterations. However, neither the protein level of the distinct ribonucleotide reductase subunits nor the dNTP pools were affected in a slt2 mutant strain. An analysis of the checkpoint function revealed that Slt2 was not required for either cell cycle arrest or the activation of the Rad53 checkpoint kinase in response to DNA damage. However, slt2 mutant cells showed an elongated bud and partially impaired Swe1 degradation after replicative stress, indicating that Slt2 could contribute, in parallel with Rad53, to bud morphogenesis control after genotoxic stresses. Conclusions Slt2 is activated by several genotoxic treatments and is required to properly cope with DNA damage. Slt

  20. Detection of phosphorylated mitogen-activated protein kinase in the developing spinal cord of the mouse embryo

    Teraishi, Toshiya; Miura, Kenji

    2011-01-01

    Highlights: → We detected physiologically phosphorylated MAPKs in developing spinal cord. → We detected physiologically phosphorylated MAPKs by an improved method. → p-ERK1/2 and p-JNK1/2 were detected in the marginal layer and the dorsal horn. → p-ERK1/2 and p-JNK1/2 might play critical roles in the developing spinal cord. → Constructing phosphoprotein atlases will be possible if expanding this work. -- Abstract: Global understanding of the proteome is a major research topic. The comprehensive visualization of the distribution of proteins in vivo or the construction of in situ protein atlases may be a valuable strategy for proteomic researchers. Information about the distribution of various proteins under physiological and pathological conditions should be extremely valuable for the basic and clinical sciences. The mitogen-activated protein kinase (MAPK) cascade plays an essential role in intracellular signaling in organisms. This cascade also regulates biological processes involving development, differentiation, and proliferation. Phosphorylation and dephosphorylation are integral reactions in regulating the activity of MAPKs. Changes in the phosphorylation state of MAPKs are rapid and reversible; therefore, the localizations of physiologically phosphorylated MAPKs in vivo are difficult to accurately detect. Furthermore, phosphorylated MAPKs are likely to change phosphorylated states through commonly used experimental manipulations. In the present study, as a step toward the construction of in situ phosphoprotein atlases, we attempted to detect physiologically phosphorylated MAPKs in vivo in developing spinal cords of mice. We previously reported an improved immunohistochemical method for detecting unstable phosphorylated MAPKs. The distribution patterns of phosphorylated MAPKs in the spinal cords of embryonic mice from embryonic day 13 (E13) to E17 were observed with an improved immunohistochemical method. Phosphorylated extracellular signal

  1. Enhanced mitogenic activity of recombinant human vascular endothelial growth factor VEGF121 expressed in E. coli Origami B (DE3) with molecular chaperones

    Kaplan, Ondřej; Zárubová, J.; Mikulová, Barbora; Filová, E.; Bártová, J.; Bačáková, L.; Brynda, Eduard

    2016-01-01

    Roč. 11, č. 10 (2016), s. 1-22, č. článku e0163697. E-ISSN 1932-6203 R&D Projects: GA MŠk(CZ) EE2.3.30.0029; GA MŠk(CZ) LQ1604; GA MŠk(CZ) ED1.1.00/02.0109; GA MZd NV15-29153A Institutional support: RVO:61389013 ; RVO:61388971 Keywords : angiogenic gene-therapy * Escherichia coli * VEGF-A Subject RIV: EB - Genetics ; Molecular Biology; EE - Microbiology, Virology (MBU-M) Impact factor: 2.806, year: 2016

  2. Silibinin and Its 2,3-Dehydro-Derivative Inhibit Basal Cell Carcinoma Growth via Suppression of Mitogenic Signaling and Transcription Factors Activation

    Tilley, C.; Deep, G.; Agarwal, Ch.; Wempe, M.F.; Biedermann, David; Valentová, Kateřina; Křen, Vladimír; Agarwal, R.

    2016-01-01

    Roč. 55, č. 1 (2016), s. 3-14 ISSN 0899-1987 R&D Projects: GA MŠk LH13097 Institutional support: RVO:61388971 Keywords : basal cell carcinoma * chemoprevention * phytochemicals Subject RIV: FR - Pharmacology ; Medidal Chemistry Impact factor: 4.185, year: 2016

  3. Calmodulin protects cells from death under normal growth conditions and mitogenic starvation but plays a mediating role in cell death upon B-cell receptor stimulation

    Schmalzigaug, R; Ye, Q; Berchtold, M W

    2001-01-01

    stimulation of the B-cell receptor (BCR), the resting Ca2+ levels remain elevated after the initial transient in CaMII-/- cells. Despite higher Ca2+ resting levels, the CaMII-/- cells are partially protected from BCR induced apoptosis indicating that CaM plays a dual role in apoptotic processes....

  4. Enhanced Mitogenic Activity of Recombinant Human Vascular Endothelial Growth Factor VEGF(121) Expressed in E. coli Origami B (DE3) with Molecular Chaperones

    Kaplan, Ondřej; Zárubová, Jana; Mikulová, Barbora; Filová, Elena; Bártová, J.; Bačáková, Lucie; Brynda, E.

    2016-01-01

    Roč. 11, č. 10 (2016), č. článku e0163697. E-ISSN 1932-6203 R&D Projects: GA MŠk(CZ) LQ1604; GA MŠk(CZ) ED1.1.00/02.0109; GA MZd NV15-29153A; GA TA ČR(CZ) TA04011345 Institutional support: RVO:67985823 Keywords : angiogenic gene-therapy * Escherichia coli * VEGF-A Subject RIV: FA - Cardiovascular Diseases incl. Cardiotharic Surgery Impact factor: 2.806, year: 2016

  5. Cathepsin D, a Marker for the Metastatic Potential of Breast Cancer, May Regulate the Mitogenic Activity of Fibroblast Growth Factor 1

    Grieb, Teri

    1998-01-01

    .... Over the years, the data substantiating such a role for cathepsin D has been quite conflicting However, there is strong evidence that cathepsin D plays a role in the degradation of the extracellular matrix (ECM...

  6. Enhancement of cell-cell contact by a nonmitogenic lectin increases blastogenic response and IL-2 release by mitogen-stimulated mouse thymocytes.

    Favero, J; Marti, J; Dornand, J; Bonnafous, J C; Mani, J C

    1986-03-01

    We have examined the influence of peanut agglutinin (PNA), a lectin which agglutinates but does not stimulate mouse thymocytes, on the responsiveness of these cells to concanavalin A (Con A) or galactose oxidase stimulation. Binding low amounts of PNA on unseparated mouse thymocytes pretreated with neuraminidase highly enhances the mitogenic response and the level of interleukin 2 release in the culture medium upon Con A stimulation. We have shown that PNA present on the cell surface acts as a crosslinking agent which favors intercellular binding between accessory cells (macrophages) and thymocytes, leading through this enhanced cooperation by cell-cell contact to an enhanced blastogenic response.

  7. The Na+/H+ exchanger, NHE1, differentially regulates mitogen-activated protein kinase subfamilies after osmotic shrinkage in Ehrlich Lettre Ascites cells

    Petersen, Stine Helene Falsig; Rasmussen, Maria; Darborg, Barbara Vasek

    2007-01-01

    Osmotic stress modulates mitogen activated protein kinase (MAPK) activities, leading to altered gene transcription and cell death/survival balance, however, the mechanisms involved are incompletely elucidated. Here, we show, using a combination of biochemical and molecular biology approaches...... by human (h) NHE1 expression in cells lacking endogenous NHE1 activity. The effect of NHE1 on ERK1/2 was pH(i)-independent and upstream of MEK1/2. Shrinkage-activation of JNK1/2 was attenuated by EIPA, augmented by hNHE1 expression, and abolished in the presence of HCO(3)(-). Basal JNK activity...

  8. Growth arrest specific protein (GAS) 6

    Haase, T N; Rasmussen, Morten; Jaksch, C A M

    2013-01-01

    using RNA microarray and quantitative PCR. The role of a differentially expressed gene, growth arrest specific protein 6 (GAS6), was evaluated in vitro using neonatal rat islets. Results The mRNA level of Gas6, known to be mitogenic in other tissues, was reduced in LP offspring. The mRNA content of Mafa...... was increased in LP offspring suggesting an early maturation of beta cells. When applied in vitro, GAS6 increased proliferation of neonatal pancreatic beta cells, while reducing glucose-stimulated insulin secretion without changing the total insulin content of the islets. In addition, GAS6 decreased the m......RNA content of Mafa. Conclusions/interpretation We propose a role for GAS6 in the regulation of pancreatic beta cells in the critical period around the time of birth. Our results support the hypothesis that the reduced beta cell mass seen in LP offspring is caused by a change in the intra-uterine environment...

  9. p38 mitogen-activated protein kinase is involved in arginase-II-mediated eNOS-uncoupling in obesity.

    Yu, Yi; Rajapakse, Angana G; Montani, Jean-Pierre; Yang, Zhihong; Ming, Xiu-Fen

    2014-07-18

    Endothelial nitric oxide synthase (eNOS)-uncoupling links obesity-associated insulin resistance and type-II diabetes to the increased incidence of cardiovascular disease. Studies have indicated that increased arginase is involved in eNOS-uncoupling through competing with the substrate L-arginine. Given that arginase-II (Arg-II) exerts some of its biological functions through crosstalk with signal transduction pathways, and that p38 mitogen-activated protein kinase (p38mapk) is involved in eNOS-uncoupling, we investigated here whether p38mapk is involved in Arg-II-mediated eNOS-uncoupling in a high fat diet (HFD)-induced obesity mouse model. Obesity was induced in wild type (WT) and Arg-II-deficient (Arg-II(-/-)) mice on C57BL/6 J background by high-fat diet (HFD, 55% fat) for 14 weeks starting from age of 7 weeks. The entire aortas were isolated and subjected to 1) immunoblotting analysis of the protein level of eNOS, Arg-II and p38mapk activation; 2) arginase activity assay; 3) endothelium-dependent and independent vasomotor responses; 4) en face staining of superoxide anion and NO production with Dihydroethidium and 4,5-Diaminofluorescein Diacetate, respectively, to assess eNOS-uncoupling. To evaluate the role of p38mapk, isolated aortas were treated with p38mapk inhibitor SB203580 (10 μmol/L, 1 h) prior to the analysis. In addition, the role of p38mapk in Arg-II-induced eNOS-uncoupling was investigated in cultured human endothelial cells overexpressing Arg-II in the absence or presence of shRNA against p38mapk. HFD enhanced Arg-II expression/activity and p38mapk activity, which was associated with eNOS-uncoupling as revealed by decreased NO and enhanced L-NAME-inhibitable superoxide in aortas of WT obese mice. In accordance, WT obese mice revealed decreased endothelium-dependent relaxations to acetylcholine despite of higher eNOS protein level, whereas Arg-II(-/-) obese mice were protected from HFD-induced eNOS-uncoupling and endothelial dysfunction, which

  10. Detection of chromosomal changes in chronic lymphocytic leukemia using classical cytogenetic methods and FISH: application of rich mitogen mixtures for lymphocyte cultures.

    Koczkodaj, Dorota; Popek, Sylwia; Zmorzyński, Szymon; Wąsik-Szczepanek, Ewa; Filip, Agata A

    2016-04-01

    One of the research methods of prognostic value in chronic lymphocytic leukemia (CLL) is cytogenetic analysis. This method requires the presence of appropriate B-cell mitogens in cultures in order to obtain a high mitotic index. The aim of our research was to determine the most effective methods of in vitro B-cell stimulation to maximize the number of metaphases from peripheral blood cells of patients with CLL for classical cytogenetic examination, and then to correlate the results with those obtained using fluorescence in situ hybridization (FISH). The study group involved 50 consecutive patients with CLL. Cell cultures were maintained with the basic composition of culture medium and addition of respective stimulators. We used the following stimulators: Pokeweed Mitogen (PWM), 12-O-tetradecanoylphorbol 13-acetate (TPA), ionophore, lipopolysaccharide (LPS), and CpG-oligonucleotide DSP30. We received the highest mitotic index when using the mixture of PWM+TPA+I+DSP30. With classical cytogenetic tests using banding techniques, numerical and structural aberrations of chromosomes were detected in 46 patients, and no change was found in only four patients. Test results clearly confirmed the legitimacy of using cell cultures enriched with the mixture of cell stimulators and combining classical cytogenetic techniques with the FISH technique in later patient diagnosing. Copyright © 2016 American Federation for Medical Research.

  11. Modulation of Cyclins, p53 and Mitogen-Activated Protein Kinases Signaling in Breast Cancer Cell Lines by 4-(3,4,5-Trimethoxyphenoxybenzoic Acid

    Kuan-Han Lee

    2014-01-01

    Full Text Available Despite the advances in cancer therapy and early detection, breast cancer remains a leading cause of cancer-related deaths among females worldwide. The aim of the current study was to investigate the antitumor activity of a novel compound, 4-(3,4,5-trimethoxyphenoxybenzoic acid (TMPBA and its mechanism of action, in breast cancer. Results indicated the relatively high sensitivity of human breast cancer cell-7 and MDA-468 cells towards TMPBA with IC50 values of 5.9 and 7.9 µM, respectively compared to hepatocarcinoma cell line Huh-7, hepatocarcinoma cell line HepG2, and cervical cancer cell line Hela cells. Mechanistically, TMPBA induced apoptotic cell death in MCF-7 cells as indicated by 4',6-diamidino-2-phenylindole (DAPI nuclear staining, cell cycle analysis and the activation of caspase-3. Western blot analysis revealed the ability of TMPBA to target pathways mediated by mitogen-activated protein (MAP kinases, 5' adenosine monophosphate-activated protein kinase (AMPK, and p53, of which the concerted action underlined its antitumor efficacy. In addition, TMPBA induced alteration of cyclin proteins’ expression and consequently modulated the cell cycle. Taken together, the current study underscores evidence that TMPBA induces apoptosis in breast cancer cells via the modulation of cyclins and p53 expression as well as the modulation of AMPK and mitogen-activated protein kinases (MAPK signaling. These findings support TMPBA’s clinical promise as a potential candidate for breast cancer therapy.

  12. PsMPK7, a stress-associated mitogen-activated protein kinase (MAPK) in Phytophthora sojae, is required for stress tolerance, reactive oxygenated species detoxification, cyst germination, sexual reproduction and infection of soybean.

    Gao, Jian; Cao, Mingna; Ye, Wenwu; Li, Haiyang; Kong, Liang; Zheng, Xiaobo; Wang, Yuanchao

    2015-01-01

    The sensing of stress signals and their transduction into appropriate responses are crucial for the adaptation, survival and infection of phytopathogenic fungi and oomycetes. Amongst evolutionarily conserved pathways, mitogen-activated protein kinase (MAPK) cascades function as key signal transducers that use phosphorylation to convey information. In this study, we identified a gene, designated PsMPK7, one of 14 predicted genes encoding MAPKs in Phytophthora sojae. PsMPK7 was highly transcribed in each tested stage, but was up-regulated in the zoospore, cyst and cyst germination stages. Silencing of PsMPK7 affected the growth of germinated cysts, oospore production and the pathogenicity of soybean. PsMPK7 transcription was induced by stresses from sorbitol, NaCl and hydrogen peroxide. Transformants in which PsMPK7 expression was silenced (PsMPK7-silenced) were significantly more sensitive to osmotic and oxidative stress. Aniline blue and diaminobenzidine staining revealed that the silenced lines did not suppress the host reactive oxygen species (ROS) burst, indicating that either the inoculated plants activated stronger defence responses to the transformants and/or the PsMPK7-silenced transformants failed to overcome plant defences. In addition, extracellular secretion of laccase decreased in the silenced lines. Overall, our results indicate that the PsMPK7 gene encodes a stress-associated MAPK in P. sojae that is important not only for responses to various stresses, but also for ROS detoxification, cyst germination, sexual oospore production and infection of soybean. © 2014 BSPP AND JOHN WILEY & SONS LTD.

  13. Growth Disorders

    ... too little of it may be very short. Treatment with growth hormone can stimulate growth. People can also have too much growth hormone. Usually the cause is a pituitary gland tumor, which is not cancer. Too much growth hormone can cause gigantism in children, where their bones and their body ...

  14. Periodic mechanical stress activates EGFR-dependent Rac1 mitogenic signals in rat nucleus pulpous cells via ERK1/2

    Gao, Gongming; Shen, Nan; Jiang, Xuefeng; Sun, Huiqing; Xu, Nanwei; Zhou, Dong; Nong, Luming; Ren, Kewei

    2016-01-01

    The mitogenic effects of periodic mechanical stress on nucleus pulpous cells have been studied extensively but the mechanisms whereby nucleus pulpous cells sense and respond to mechanical stimulation remain a matter of debate. We explored this question by performing cell culture experiments in our self-developed periodic stress field and perfusion culture system. Under periodic mechanical stress, rat nucleus pulpous cell proliferation was significantly increased (p < 0.05 for each) and was associated with increases in the phosphorylation and activation of EGFR, Rac1, and ERK1/2 (p < 0.05 for each). Pretreatment with the ERK1/2 selective inhibitor PD98059 reduced periodic mechanical stress-induced nucleus pulpous cell proliferation (p < 0.05 for each), while the activation levels of EGFR and Rac1 were not inhibited. Proliferation and phosphorylation of ERK1/2 were inhibited after pretreatment with the Rac1 inhibitor NSC23766 in nucleus pulpous cells in response to periodic mechanical stress (p < 0.05 for each), while the phosphorylation site of EGFR was not affected. Inhibition of EGFR activity with AG1478 abrogated nucleus pulpous cell proliferation (p < 0.05 for each) and attenuated Rac1 and ERK1/2 activation in nucleus pulpous cells subjected to periodic mechanical stress (p < 0.05 for each). These findings suggest that periodic mechanical stress promotes nucleus pulpous cell proliferation in part through the EGFR-Rac1-ERK1/2 signaling pathway, which links these three important signaling molecules into a mitogenic cascade. - Highlights: • The mechanism involved in nucleus pulpous cells to respond to mechanical stimuli. • Periodic mechanical stress can stimulate the phosphorylation of EGFR. • EGFR activates Rac1 and leads to rat nucleus pulpous cell proliferation. • EGFR and Rac1 activate ERK1/2 mitogenic signals in nucleus pulpous cells. • EGFR-Rac1-ERK1/2 is constitutes at least one critical signal transduction pathway.

  15. Periodic mechanical stress activates EGFR-dependent Rac1 mitogenic signals in rat nucleus pulpous cells via ERK1/2

    Gao, Gongming [Department of Orthopedics, The Affiliated Changzhou No. 2 Hospital of Nanjing Medical University, Changzhou 213003 (China); Shen, Nan [Department of Clinical Pharmacy, The Affiliated Jiangyin Hospital of Southeast University Medical School, Jiangyin 214400 (China); Jiang, Xuefeng; Sun, Huiqing [Department of Orthopedics, The Affiliated Jiangyin Hospital of Southeast University Medical School, Jiangyin 214400 (China); Xu, Nanwei; Zhou, Dong [Department of Orthopedics, The Affiliated Changzhou No. 2 Hospital of Nanjing Medical University, Changzhou 213003 (China); Nong, Luming, E-mail: lumingnong@hotmail.com [Department of Orthopedics, The Affiliated Changzhou No. 2 Hospital of Nanjing Medical University, Changzhou 213003 (China); Ren, Kewei, E-mail: keweiren@hotmail.com [Department of Orthopedics, The Affiliated Jiangyin Hospital of Southeast University Medical School, Jiangyin 214400 (China)

    2016-01-15

    The mitogenic effects of periodic mechanical stress on nucleus pulpous cells have been studied extensively but the mechanisms whereby nucleus pulpous cells sense and respond to mechanical stimulation remain a matter of debate. We explored this question by performing cell culture experiments in our self-developed periodic stress field and perfusion culture system. Under periodic mechanical stress, rat nucleus pulpous cell proliferation was significantly increased (p < 0.05 for each) and was associated with increases in the phosphorylation and activation of EGFR, Rac1, and ERK1/2 (p < 0.05 for each). Pretreatment with the ERK1/2 selective inhibitor PD98059 reduced periodic mechanical stress-induced nucleus pulpous cell proliferation (p < 0.05 for each), while the activation levels of EGFR and Rac1 were not inhibited. Proliferation and phosphorylation of ERK1/2 were inhibited after pretreatment with the Rac1 inhibitor NSC23766 in nucleus pulpous cells in response to periodic mechanical stress (p < 0.05 for each), while the phosphorylation site of EGFR was not affected. Inhibition of EGFR activity with AG1478 abrogated nucleus pulpous cell proliferation (p < 0.05 for each) and attenuated Rac1 and ERK1/2 activation in nucleus pulpous cells subjected to periodic mechanical stress (p < 0.05 for each). These findings suggest that periodic mechanical stress promotes nucleus pulpous cell proliferation in part through the EGFR-Rac1-ERK1/2 signaling pathway, which links these three important signaling molecules into a mitogenic cascade. - Highlights: • The mechanism involved in nucleus pulpous cells to respond to mechanical stimuli. • Periodic mechanical stress can stimulate the phosphorylation of EGFR. • EGFR activates Rac1 and leads to rat nucleus pulpous cell proliferation. • EGFR and Rac1 activate ERK1/2 mitogenic signals in nucleus pulpous cells. • EGFR-Rac1-ERK1/2 is constitutes at least one critical signal transduction pathway.

  16. growth stimulant

    Effects of timing and duration of supplementation of LIVFIT VET ® (growth stimulant) as substitute for fish meal on the growth performance, haematology and clinical enzymes concentration of growing pigs.

  17. Insulin growth factors regulate the mitotic cycle in cultured rat sympathetic neuroblasts

    DiCicco-Bloom, E.; Black, I.B.

    1988-01-01

    While neuronal mitosis is uniquely restricted to early development, the underlying regulation remains to be defined. The authors have now developed a dissociated, embryonic sympathetic neuron culture system that uses fully defined medium in which cells enter the mitotic cycle. The cultured cells expressed two neuronal traits, tyrosine hydroxylase and the neuron-specific 160-kDa neurofilament subunit protein, but were devoid of glial fibrillary acidic protein, a marker for non-myelin-forming Schwann cells in ganglia. Approximately one-third of the tyrosine hydroxylase-positive cells synthesized DNA in culture, specifically incorporating [ 3 H]thymidine into their nuclei. They used this system to define factors regulating the mitotic cycle in sympathetic neuroblasts. Members of the insulin family of growth factors, including insulin and insulin-like growth factors I and II, regulated DNA synthesis in the presumptive neuroblasts. Insulin more than doubled the proportion of tyrosine hydroxylase-positive cells entering the mitotic cycle, as indicated by autoradiography of [ 3 H]thymidine incorporation into nuclei. Scintillation spectrometry was an even more sensitive index of DNA synthesis. In contrast, the trophic protein nerve growth factor exhibited no mitogenic effect, suggesting that the mitogenic action of insulin growth factors is highly specific. The observations are discussed in the context of the detection of insulin growth factors and receptors in the developing brain

  18. HIV-induced immunodeficiency. Relatively preserved phytohemagglutinin as opposed to decreased pokeweed mitogen responses may be due to possibly preserved responses via CD2/phytohemagglutinin pathway

    Hofmann, B; Jakobsen, K D; Odum, N

    1989-01-01

    and eight controls were chosen for the following studies. Expression of T3, Ti, delta receptors, and CD2 was investigated and showed an increased percentage of CD2 receptors positive cells in HIV seropositive subjects without AIDS. The proliferative responses of PBL to stimulation with PHA, PWM, antibodies....... In patients, these responses were less suppressed than the responses to PWM indicating that stimulation with mitogens is more complex than a simple stimulation of Ti/T3 and CD2 receptors. Further investigations were done on resting T cells, i.e., lymphocytes depleted of macrophages and pre-activated cells....... Addition of PHA to these cells resulted in preactivation with expression of IL-2R (CD25) but not in proliferation. In contrast, addition of PHA plus SRBC, which bind to the CD2 receptors caused IL-2R expression, IL-2 production, and proliferation. Addition of PWM + SRBC did not result in proliferation...

  19. Ménage à trois: the complex relationships between mitogen-activated protein kinases, WRKY transcription factors, and VQ-motif-containing proteins.

    Weyhe, Martin; Eschen-Lippold, Lennart; Pecher, Pascal; Scheel, Dierk; Lee, Justin

    2014-01-01

    Out of the 34 members of the VQ-motif-containing protein (VQP) family, 10 are phosphorylated by the mitogen-activated protein kinases (MAPKs), MPK3 and MPK6. Most of these MPK3/6-targeted VQPs (MVQs) interacted with specific sub-groups of WRKY transcription factors in a VQ-motif-dependent manner. In some cases, the MAPK appears to phosphorylate either the MVQ or the WRKY, while in other cases, both proteins have been reported to act as MAPK substrates. We propose a network of dynamic interactions between members from the MAPK, MVQ and WRKY families - either as binary or as tripartite interactions. The compositions of the WRKY-MVQ transcriptional protein complexes may change - for instance, through MPK3/6-mediated modulation of protein stability - and therefore control defense gene transcription.

  20. Constitutive Activation of the Fission Yeast Pheromone-Responsive Pathway Induces Ectopic Meiosis and Reveals Ste11 as a Mitogen-Activated Protein Kinase Target

    Kjærulff, Søren; Lautrup-Larsen, I.; Truelsen, S.

    2005-01-01

    In the fission yeast Schizosaccharomyces pombe, meiosis normally takes place in diploid zygotes resulting from conjugation of haploid cells. In the present study, we report that the expression of a constitutively activated version of the pheromone-responsive mitogen-activated protein kinase kinase...... found that haploid meiosis was dramatically reduced when Ste11 was mutated to mimic phosphorylation by Pat1. The mutation of two putative MAPK sites in Ste11 also dramatically reduced the level of haploid meiosis, suggesting that Ste11 is a direct target of Spk1. Supporting this, we show that Spk1 can...... interact physically with Ste11 and also phosphorylate the transcription factor in vitro. Finally, we demonstrate that ste11 is required for pheromone-induced G1 arrest. Interestingly, when we mutated Ste11 in the sites for Pat1 and Spk1 phosphorylation simultaneously, the cells could still arrest in G1...

  1. A Role for Mitogen- and Stress-Activated Kinase 1 in L-DOPA-Induced Dyskinesia and ∆FosB Expression

    Feyder, Michael; Södersten, Erik; Santini, Emanuela

    2014-01-01

    BACKGROUND: Abnormal regulation of extracellular signal-regulated kinases 1 and 2 has been implicated in 3,4-dihydroxy-l-phenylalanine (L-DOPA)-induced dyskinesia (LID), a motor complication affecting Parkinson's disease patients subjected to standard pharmacotherapy. We examined the involvement...... of mitogen- and stress-activated kinase 1 (MSK1), a downstream target of extracellular signal-regulated kinases 1 and 2, and an important regulator of transcription in LID. METHODS: 6-Hydroxydopamine was used to produce a model of Parkinson's disease in MSK1 knockout mice and in ∆FosB- or ∆c......Jun-overexpressing transgenic mice, which were assessed for LID following long-term L-DOPA administration. Biochemical processes were evaluated by Western blotting or immunofluorescence. Histone H3 phosphorylation was analyzed by chromatin immunoprecipitation followed by promotor-specific quantitative polymerase chain reaction...

  2. Eotaxin induces degranulation and chemotaxis of eosinophils through the activation of ERK2 and p38 mitogen-activated protein kinases

    Kampen, G T; Stafford, S; Adachi, T

    2000-01-01

    Eotaxin and other CC chemokines acting via CC chemokine receptor-3 (CCR3) are believed to play an integral role in the development of eosinophilic inflammation in asthma and allergic inflammatory diseases. However, little is known about the intracellular events following agonist binding to CCR3...... and the relationship of these events to the functional response of the cell. The objectives of this study were to investigate CCR3-mediated activation of the mitogen-activated protein (MAP) kinases extracellular signal-regulated kinase-2 (ERK2), p38, and c-jun N-terminal kinase (JNK) in eosinophils and to assess...... the requirement for MAP kinases in eotaxin-induced eosinophil cationic protein (ECP) release and chemotaxis. MAP kinase activation was studied in eotaxin-stimulated eosinophils (more than 97% purity) by Western blotting and immune-complex kinase assays. ECP release was measured by radioimmunoassay. Chemotaxis...

  3. Platelet-Derived Growth Factor-Receptor α Strongly Inhibits Melanoma Growth In Vitro and In Vivo

    Debora Faraone

    2009-08-01

    Full Text Available Cutaneous melanoma is the most aggressive skin cancer; it is highly metastatic and responds poorly to current therapies. The expression of platelet-derived growth factor receptors (PDGF-Rs is reported to be reduced in metastatic melanoma compared with benign nevi or normal skin; we then hypothesized that PDGF-Rα may control growth of melanoma cells. We show here that melanoma cells overexpressing PDGF-Rα respond to serum with a significantly lower proliferation compared with that of controls. Apoptosis, cell cycle arrest, pRb dephosphorylation, and DNA synthesis inhibition were also observed in cells overexpressing PDGF-Rα. Proliferation was rescued by PDGF-Rα inhibitors, allowing to exclude nonspecific toxic effects and indicating that PDGF-Rα mediates autocrine antiproliferation signals in melanoma cells. Accordingly, PDGF-Rα was found to mediate staurosporine cytotoxicity. A protein array-based analysis of the mitogen-activated protein kinase pathway revealed that melanoma cells overexpressing PDGF-Rα show a strong reduction of c-Jun phosphorylated in serine 63 and of protein phosphatase 2A/Bα and a marked increase of p38γ, mitogen-activated protein kinase kinase 3, and signal regulatory protein α1 protein expression. In a mouse model of primary melanoma growth, infection with the Ad-vector overexpressing PDGF-Rα reached a significant 70% inhibition of primary melanoma growth (P < .001 and a similar inhibition of tumor angiogenesis. All together, these data demonstrate that PDGF-Rα strongly impairs melanoma growth likely through autocrine mechanisms and indicate a novel endogenous mechanism involved in melanoma control.

  4. Regulator of differentiation 1 (ROD1) binds to the amphipathic C-terminal peptide of thrombospondin-4 and is involved in its mitogenic activity.

    Sadvakassova, Gulzhakhan; Dobocan, Monica C; Difalco, Marcos R; Congote, Luis F

    2009-09-01

    The matrix protein thrombospondin-4 has an acidic amphipathic C-terminal peptide (C21) which stimulates erythroid cell proliferation. Here we show that C21 stimulates red cell formation in anemic mice in vivo. In vitro experiments indicated that the peptide-mediated increase of erythroid colony formation in cultures of human CD34+ hematopoietic progenitor cells was possible only under continuous presence of erythropoietin. In the absence of this cytokine, C21 stimulated exclusively myeloid colony formation. Therefore, the peptide is not a specific erythroid differentiation factor. In fact, it is mitogenic in non-erythroid cells, such as skin fibroblasts and kidney epithelial cells. In erythroleukemic TF-1 cells, it actually decreased the production of the erythroid differentiation marker glycophorin A. C21-affinity chromatography revealed regulator of differentiation 1 (ROD1) as a major C21-binding protein. ROD1 is the hematopoietic cell paralog of polypyrimidine tract binding proteins (PTBs), RNA splice regulators which regulate differentiation by repressing tissue-specific exons. ROD1 binding to C21 was strongly inhibited by synthetic RNAs in the order poly A > poly U > poly G = poly C and was weakly inhibited by a synthetic phosphorylated peptide mimicking the C-terminal domain of RNA polymerase II. Cellular overexpression or knockdown experiments of ROD1 suggest a role for this protein in the mitogenic activity of C21. Since the nuclear proteins ROD1 and PTBs regulate differentiation at a posttranscriptional level and there is a fast nuclear uptake of C21, we put forward the idea that the peptide is internalized, goes to the nucleus and maintains cells in a proliferative state by supporting ROD1-mediated inhibition of differentiation.

  5. Stress and vascular responses: atheroprotective effect of laminar fluid shear stress in endothelial cells: possible role of mitogen-activated protein kinases.

    Yoshizumi, Masanori; Abe, Jun-Ichi; Tsuchiya, Koichiro; Berk, Bradford C; Tamaki, Toshiaki

    2003-03-01

    Atherosclerosis preferentially occurs in areas of turbulent blood flow and low fluid shear stress, whereas laminar blood flow and high shear stress are atheroprotective. Inflammatory cytokines, such as tumor necrosis factor-alpha (TNF-alpha), stimulate expression of endothelial cell (EC) genes that may promote atherosclerosis. Recent findings suggest a steady laminar blood flow decreases EC apoptosis and inhibits TNF-mediated EC activation. EC apoptosis or activation is suggested to be involved in plaque erosion, which may lead to platelet aggregation. TNF-alpha regulates gene expression in ECs, in part, by stimulating mitogen-activated protein (MAP) kinases, which phosphorylate transcription factors. We hypothesized that steady laminar flow inhibits cytokine-mediated activation of MAP kinases in ECs. To test this hypothesis, we determined the effects of steady laminar flow (shear stress = 12 dynes/cm(2)) on TNF-alpha-stimulated activity of three MAP kinases in human umbilical vein ECs (HUVEC): extracellular signal-regulated kinase (ERK1/2), c-Jun N-terminal kinase (JNK), and p38. TNF-alpha activated ERK1/2, JNK, and p38 maximally at 15 min in HUVEC. Pre-exposing HUVEC for 10 min to flow inhibited TNF-alpha activation of JNK, but showed no significant effect on ERK1/2 or p38 activation. Incubation of HUVEC with PD98059, a specific ERK1/2 inhibitor, blocked the flow-mediated inhibition of TNF activation of JNK. Transfection studies with dominant-negative constructs of the protein kinase MEK5 suggested an important role for big mitogen-activated protein kinase 1 (BMK1) in flow-mediated regulation of EC activation by TNF-alpha. Understanding the mechanisms by which steady laminar flow regulates JNK activation by cytokines may provide insight into the atheroprotective mechanisms induced by laminar blood flow.

  6. Ebselen impairs cellular oxidative state and induces endoplasmic reticulum stress and activation of crucial mitogen-activated protein kinases in pancreatic tumour AR42J cells.

    Santofimia-Castaño, Patricia; Izquierdo-Alvarez, Alicia; Plaza-Davila, María; Martinez-Ruiz, Antonio; Fernandez-Bermejo, Miguel; Mateos-Rodriguez, Jose M; Salido, Gines M; Gonzalez, Antonio

    2018-01-01

    Ebselen (2-phenyl-1,2-benzisoselenazol-3(2H)-one) is an organoselenium radical scavenger compound, which has strong antioxidant and anti-inflammatory effects. However, evidence suggests that this compound could exert deleterious actions on cell physiology. In this study, we have analyzed the effect of ebselen on rat pancreatic AR42J cells. Cytosolic free-Ca 2+ concentration ([Ca 2+ ] c ), cellular oxidative status, setting of endoplasmic reticulum stress, and phosphorylation of major mitogen-activated protein kinases were analyzed. Our results show that ebselen evoked a concentration-dependent increase in [Ca 2+ ] c . The compound induced an increase in the generation of reactive oxygen species in the mitochondria. We also observed an increase in global cysteine oxidation in the presence of ebselen. In the presence of ebselen an impairment of cholecystokinin-evoked amylase release was noted. Moreover, involvement of the unfolded protein response markers, ER chaperone and signaling regulator GRP78/BiP, eukaryotic translation initiation factor 2α and X-box binding protein 1 was detected. Finally, increases in the phosphorylation of SAPK/JNK, p38 MAPK, and p44/42 MAPK in the presence of ebselen were also observed. Our results provide evidences for an impairment of cellular oxidative state and enzyme secretion, the induction of endoplasmic reticulum stress and the activation of crucial mitogen-activated protein kinases in the presence of ebselen. As a consequence ebselen exerts a potential toxic effect on AR42J cells. © 2017 Wiley Periodicals, Inc.

  7. Lung-derived growth factors: possible paracrine effectors of fetal lung development

    Montes, A.M.

    1985-01-01

    A potential role for paracrine secretions in lung organogenesis has been hypothesized (Alescio and Piperno, 1957). These studies present direct support for the paracrine model by demonstrating the presence of locally produced mitogenic/maturational factors in fetal rat lung tissue. Conditioned serum free medium (CSFM) from nineteen-day fetal rat lung cultures was shown to contain several bioactive peptides as detected by 3 H-Thymidine incorporation into chick embryo and rat lung fibroblasts, as well as 14 C-choline incorporation into surfactant in mixed cell cultures. Using ion-exchange chromatography and Sephadex gel filtration, a partially purified mitogen, 11-III, was obtained. The partially purified 11-III stimulates mitosis in chick embryo fibroblasts and post-natal rat lung fibroblasts. Multiplication in fetal rat lung fibroblasts cultures is stimulated only when these are pre-incubated with a competence factor or unprocessed CSFM. This suggests the existence of an endogenously produced competence factor important in the regulation of fetal lung growth. Preparation 11-III does not possess surfactant stimulating activity as assessed by 3 H-choline incorporation into lipids in predominantly type-II cell cultures. These data demonstrate the presence of a maturational/mitogenic factor, influencing type-II mixed cell cultures. In addition, 11-III had been shown to play an autocrine role stimulating the proliferation of fetal lung fibroblasts. Finally, these data suggest the existence of a local produced competence factor

  8. Synthesis and secretion of platelet-derived growth factor by human breast cancer cell lines

    Bronzert, D.A.; Pantazis, P.; Antoniades, H.N.; Kasid, A.; Davidson, N.; Dickson, R.B.; Lippman, M.E.

    1987-01-01

    The authors report that human breast cancer cells secrete a growth factor that is biologically and immunologically similar to platelet-derived growth factor (PDGF). Serum-free medium conditioned by estrogen-independent MDA-MB-231 or estrogen-dependent MCF-7 cells contains a mitogenic or competence activity that is capable of inducing incorporation of [ 3 H] thymidine into quiescent Swiss 3T3 cells in the presence of platelet-poor plasma. Like authentic PDGF, the PDGF-like activity produced by breast cancer cells is stable after acid and heat treatment (95 0 C) and inhibited by reducing agents. The mitogenic activity comigrates with a material of ≅30 kDa on NaDodSO 4 /polyacrylamide gels. Immunoprecipitation with PDGF antiserum of proteins from metabolically labeled cell lysates and conditioned medium followed by analysis on nonreducing NaDodSO 4 /polyacrylamide gels identified proteins of 30 and 34 kDa. Upon reduction, the 30- and 34-kDa bands were converted to 15- and 16-kDa bands suggesting that the immunoprecipitated proteins were made up of two disulfide-linked polypeptides similar to PDGF. Hybridization studies with cDNA probes for the A chain PDGF and the B chain of PDGF/SIS identified transcripts for both PDGF chains in the MCF-7 and MDA-MB-231 cells. The data summarized above provide conclusive evidence for the synthesis and hormonally regulated secretion of a PDGF-like mitogen by breast carcinoma cells. Production of a PDGF-like growth factor by breast cancer cell lines may be important in mediating paracrine stimulation of tumor growth

  9. Inhibition of Curcumin on ZAKα Activity Resultant in Apoptosis and Anchorage-Independent Growth in Cancer Cells.

    Lee, Jin-Sun; Wang, Tsu-Shing; Lin, Ming Cheng; Lin, Wei-Wen; Yang, Jaw-Ji

    2017-10-31

    Curcumin, a popular yellow pigment of the dietary spice turmeric, has been reported to inhibit cell growth and to induce apoptosis in a wide variety of cancer cells. Although numerous studies have investigated anticancer effects of curcumin, the precise molecular mechanism of action remains unidentified. Whereas curcumin mediates cell survival and apoptosis through mitogen-activated protein kinase (MAPK) and nuclear factor-kappa B (NF-κB) signaling cascades, its impact on the upstream regulation of MAPK is unclear. The leucine-zipper and sterile-α motif kinase alpha (ZAKα), a mitogen-activated protein kinase kinase kinase (MAP3K), activates the c-Jun N-terminal kinase (JNK) and NF-κB pathway. This paper investigated the prospective involvement of ZAKα in curcumin-induced effects on cancer cells. Our results suggest that the antitumor activity of curcumin is mediated via a mechanism involving inhibition of ZAKα activity.

  10. Expressing OsMPK4 Impairs Plant Growth but Enhances the Resistance of Rice to the Striped Stem Borer Chilo suppressalis

    Xiaoli Liu; Jiancai Li; Liping Xu; Qi Wang; Yonggen Lou

    2018-01-01

    Mitogen-activated protein kinases (MPKs) play a central role not only in plant growth and development, but also in plant responses to abiotic and biotic stresses, including pathogens. Yet, their role in herbivore-induced plant defenses and their underlying mechanisms remain largely unknown. Here, we cloned a rice MPK gene, OsMPK4, whose expression was induced by mechanical wounding, infestation of the striped stem borer (SSB) Chilo suppressalis, and treatment with jasmonic acid (JA), but not ...

  11. Regulation of insulin-like growth factor I receptors on vascular smooth muscle cells by growth factors and phorbol esters.

    Ververis, J J; Ku, L; Delafontaine, P

    1993-06-01

    Insulin-like growth factor I (IGF I) is an important mitogen for vascular smooth muscle cells. To characterize regulation of vascular IGF I receptors, we performed radioligand displacement experiments using rat aortic smooth muscle cells (RASMs). Serum deprivation for 48 hours caused a 40% decrease in IGF I receptor number. Exposure of quiescent RASMs to platelet-derived growth factor (PDGF), fibroblast growth factor (FGF), or angiotensin II (Ang II) caused a 1.5-2.0-fold increase in IGF I receptors per cell. After FGF exposure, there was a marked increase in the mitogenic response to IGF I. IGF I downregulated its receptors in the presence of platelet-poor plasma. Stimulation of protein kinase C (PKC) by exposure of quiescent RASMs to phorbol 12-myristate 13-acetate caused a biphasic response in IGF I binding; there was a 42% decrease in receptor number at 45 minutes and a 238% increase at 24 hours. To determine the role of PKC in growth factor-induced regulation of IGF I receptors, we downregulated PKC by exposing RASMs to phorbol 12,13-dibutyrate (PDBu) for 48 hours. PDGF- and FGF- but not Ang II-mediated upregulation of IGF I receptors was completely inhibited in PDBu-treated cells. Thus, acute PKC activation by phorbol esters inhibits IGF I binding, whereas chronic PKC activation increases IGF I binding. PDGF and FGF but not Ang II regulate vascular IGF I receptors through a PKC-dependent pathway. These data provide new insights into the regulation of vascular smooth muscle cell IGF I receptors in vitro and are of potential importance in characterizing vascular proliferative responses in vivo.

  12. Ghrelin protects against depleted uranium-induced apoptosis of MC3T3-E1 cells through oxidative stress-mediated p38-mitogen-activated protein kinase pathway

    Hao, Yuhui; Liu, Cong; Huang, Jiawei; Gu, Ying; Li, Hong; Yang, Zhangyou; Liu, Jing [State Key Laboratory of Trauma, Burns and Combined Injury, Institute of Combined Injury, Chongqing Engineering Research Center for Nanomedicine, College of Preventive Medicine, Third Military Medical University, No. 30 Gaotanyan Street, Shapingba District, Chongqing 400038 (China); Wang, Weidong, E-mail: wwdwyl@sina.com [Department of Radiation Oncology, Shanghai Jiao Tong University Affiliated Sixth People Hospital, Shanghai 200233 (China); Li, Rong, E-mail: yuhui_hao@126.com [State Key Laboratory of Trauma, Burns and Combined Injury, Institute of Combined Injury, Chongqing Engineering Research Center for Nanomedicine, College of Preventive Medicine, Third Military Medical University, No. 30 Gaotanyan Street, Shapingba District, Chongqing 400038 (China)

    2016-01-01

    Depleted uranium (DU) mainly accumulates in the bone over the long term. Osteoblast cells are responsible for the formation of bone, and they are sensitive to DU damage. However, studies investigating methods of reducing DU damage in osteoblasts are rarely reported. Ghrelin is a stomach hormone that stimulates growth hormones released from the hypothalamic–pituitary axis, and it is believed to play an important physiological role in bone metabolism. This study evaluates the impact of ghrelin on DU-induced apoptosis of the osteoblast MC3T3-E1 and investigates its underlying mechanisms. The results show that ghrelin relieved the intracellular oxidative stress induced by DU, eliminated reactive oxygen species (ROS) and reduced lipid peroxidation by increasing intracellular GSH levels; in addition, ghrelin effectively suppressed apoptosis, enhanced mitochondrial membrane potential, and inhibited cytochrome c release and caspase-3 activation after DU exposure. Moreover, ghrelin significantly reduced the expression of DU-induced phosphorylated p38-mitogen-activated protein kinase (MAPK). A specific inhibitor (SB203580) or specific siRNA of p38-MAPK could significantly suppress DU-induced apoptosis and related signals, whereas ROS production was not affected. In addition, ghrelin receptor inhibition could reduce the anti-apoptosis effect of ghrelin on DU and reverse the effect of ghrelin on intracellular ROS and p38-MAPK after DU exposure. These results suggest that ghrelin can suppress DU-induced apoptosis of MC3T3-E1 cells, reduce DU-induced oxidative stress by interacting with its receptor, and inhibit downstream p38-MAPK activation, thereby suppressing the mitochondrial-dependent apoptosis pathway. - Highlights: • Ghrelin suppressed DU-induced apoptosis of MC3T3-E1 cells. • Ghrelin inhibited DU-induced oxidative stress and further p38-MAPK activation. • Ghrelin further suppressed mitochondrial-dependent apoptosis pathway. • The anti-oxidation effect of

  13. Growth references

    Buuren, S. van

    2007-01-01

    A growth reference describes the variation of an anthropometric measurement within a group of individuals. A reference is a tool for grouping and analyzing data and provides a common basis for comparing populations.1 A well known type of reference is the age-conditional growth diagram. The

  14. P38 mitogen-activated protein kinase (p38 MAPK) overexpression in clinical staging of nasopharyngeal carcinoma

    Farhat; Asnir, R. A.; Yudhistira, A.; Daulay, E. R.; Muzakkir, M. M.; Yulius, S.

    2018-03-01

    Molecular biological research on nasopharyngeal carcinoma has been widely practiced, such as VEGF, EGFR, COX-2 expression and so on. MAPK plays a role in cell growth such as proliferation, differentiation, and apoptosis, primarily contributing to gene expression, where p38 MAPK pathway mostly associate with anti-apoptosis and cause cell transformation. The aim of this study is to determine the expression of p38 MAPK in clinical stage of nasopharyngeal carcinoma so that the result can be helpful in prognosis and adjunctive therapy in nasopharyngeal carcinoma. The research design is descriptive. It was done in THT- KL Department of FK USU/RSUP Haji Adam Malik, Medan and Pathology Anatomical Department of FK USU. The study was conducted from December 2011 to May 2012. The Samples are all patients who diagnosed with nasopharyngeal carcinoma in oncology division of Otorhinolaryngology Department. p38 MAPK overexpression was found in 21 samples (70%) from 30 nasopharyngeal carcinoma samples. The elevated of p38 MAPK expression most found on T4 by eight samples (38.1%), N3 lymph node group by nine samples (42.9%), stage IV of clinical staging is as many as 15 samples (71.4%). p38 MAPK most expressed in stage IV clinical staging of patients with nasopharyngeal carcinoma.

  15. Valsartan attenuates pulmonary hypertension via suppression of mitogen activated protein kinase signaling and matrix metalloproteinase expression in rodents.

    Lu, Yuyan; Guo, Haipeng; Sun, Yuxi; Pan, Xin; Dong, Jia; Gao, Di; Chen, Wei; Xu, Yawei; Xu, Dachun

    2017-08-01

    It has previously been demonstrated that the renin-angiotensin system is involved in the pathogenesis and development of pulmonary hypertension (PH). However, the efficacy of angiotensin II type I (AT1) receptor blockers in the treatment of PH is variable. The present study examined the effects of the AT1 receptor blocker valsartan on monocrotaline (MCT)‑induced PH in rats and chronic hypoxia‑induced PH in mice. The results demonstrated that valsartan markedly attenuated development of PH in rats and mice, as indicated by reduced right ventricular systolic pressure, diminished lung vascular remodeling and decreased right ventricular hypertrophy, compared with vehicle treated animals. Immunohistochemical analyses of proliferating cell nuclear antigen expression revealed that valsartan suppressed smooth muscle cell proliferation. Western blot analysis demonstrated that valsartan limited activation of p38, c‑Jun N‑terminal kinase 1/2 and extracellular signal‑regulated kinase 1/2 signaling pathways and significantly reduced MCT‑induced upregulation of pulmonary matrix metalloproteinases‑2 and ‑9, and transforming growth factor‑β1 expression. The results suggested that valsartan attenuates development of PH in rodents by reducing expression of extracellular matrix remodeling factors and limiting smooth muscle cell proliferation to decrease pathological vascular remodeling. Therefore, valsartan may be a valuable future therapeutic approach for the treatment of PH.

  16. Role of Akt/PKB and PFKFB isoenzymes in the control of glycolysis, cell proliferation and protein synthesis in mitogen-stimulated thymocytes.

    Houddane, Amina; Bultot, Laurent; Novellasdemunt, Laura; Johanns, Manuel; Gueuning, Marie-Agnès; Vertommen, Didier; Coulie, Pierre G; Bartrons, Ramon; Hue, Louis; Rider, Mark H

    2017-06-01

    Proliferating cells depend on glycolysis mainly to supply precursors for macromolecular synthesis. Fructose 2,6-bisphosphate (Fru-2,6-P 2 ) is the most potent positive allosteric effector of 6-phosphofructo-1-kinase (PFK-1), and hence of glycolysis. Mitogen stimulation of rat thymocytes with concanavalin A (ConA) led to time-dependent increases in lactate accumulation (6-fold), Fru-2,6-P 2 content (4-fold), 6-phosphofructo-2-kinase (PFK-2)/fructose-2,6-bisphosphatase isoenzyme 3 and 4 (PFKFB3 and PFKFB4) protein levels (~2-fold and ~15-fold, respectively) and rates of cell proliferation (~40-fold) and protein synthesis (10-fold) after 68h of incubation compared with resting cells. After 54h of ConA stimulation, PFKFB3 mRNA levels were 45-fold higher than those of PFKFB4 mRNA. Although PFKFB3 could be phosphorylated at Ser461 by protein kinase B (PKB) in vitro leading to PFK-2 activation, PFKFB3 Ser461 phosphorylation was barely detectable in resting cells and only increased slightly in ConA-stimulated cells. On the other hand, PFKFB3 and PFKFB4 mRNA levels were decreased (90% and 70%, respectively) by exposure of ConA-stimulated cells to low doses of PKB inhibitor (MK-2206), suggesting control of expression of the two PFKFB isoenzymes by PKB. Incubation of thymocytes with ConA resulted in increased expression and phosphorylation of the translation factors eukaryotic initiation factor-4E-binding protein-1 (4E-BP1) and ribosomal protein S6 (rpS6). Treatment of ConA-stimulated thymocytes with PFK-2 inhibitor (3PO) or MK-2206 led to significant decreases in Fru-2,6-P 2 content, medium lactate accumulation and rates of cell proliferation and protein synthesis. These data were confirmed by using siRNA knockdown of PFKFB3, PFKFB4 and PKB α/β in the more easily transfectable Jurkat E6-1 cell line. The findings suggest that increased PFKFB3 and PFKFB4 expression, but not increased PFKFB3 Ser461 phosphorylation, plays a role in increasing glycolysis in mitogen

  17. Induction of glutathione synthesis in human hepatocytes by acute and chronic arsenic exposure: Differential roles of mitogen-activated protein kinases

    Hou, Yongyong; Wang, Yi; Wang, Huihui; Xu, Yuanyuan

    2014-01-01

    Highlights: • Arsenic exposure increased intracellular levels of glutathione. • Mitogen-activated protein kinases were involved in glutathione homeostasis. • ERK contributed to glutathione synthesis during acute arsenic exposure. • Glutathione synthesis was regulated by p38 at least in part independent of NRF2 during chronic arsenic exposure. - Abstract: Glutathione (GSH) is a vital component of antioxidant defense which protects cells from toxic insults. Previously we found intracellular GSH was involved in cell resistance against arsenic-induced cytotoxicity. However, molecular mechanisms of GSH homeostasis during arsenic exposure are largely undefined. Here, we investigated roles of mitogen-activated protein kinases (MAPKs) in GSH synthesis pathway with two arsenic exposure strategies by using Chang human hepatocytes. In one strategy, acute arsenic exposure (20 μM, 24 h) was applied, as MAPK signaling is generally considered to be transient. In the other one, chronic arsenic exposure (500 nM, 20 weeks) was applied, which mimicked the general human exposure to arsenic. We found that acute arsenic exposure activated extracellular signal-regulated 1/2 kinases (ERK1/2) and c-Jun N-terminal kinase (JNK) in parallel with increased transcription and nuclear translocation of factor-erythroid 2-related factor 2 (NRF2) and enhanced expression of γ-glutamyl cysteine ligase catalytic subunit (GCLC), resulting in elevated intracellular GSH levels. Specific ERK inhibitor abolished arsenic-induced NRF2 nuclear translocation and GSH synthesis. During chronic arsenic exposure which induced a malignant cellular phenotype, continuous p38 activation and NRF2 nuclear translocation were observed with enhanced GSH synthesis. Specific p38 inhibitor attenuated arsenic-enhanced GSH synthesis without changing NRF2 nuclear translocation. Taken together, our results indicate MAPK pathways play an important role in cellular GSH homeostasis in response to arsenic. However, the

  18. Cultured human foreskin fibroblasts produce a factor that stimulates their growth with properties similar to basic fibroblast growth factor

    Story, M.T.

    1989-01-01

    To determine if fibroblasts could be a source of fibroblast growth factor (FGF) in tissue, cells were initiated in culture from newborn human foreskin. Fibroblast cell lysates promoted radiolabeled thymidine uptake by cultured quiescent fibroblasts. Seventy-nine percent of the growth-promoting activity of lysates was recovered from heparin-Sepharose. The heparin-binding growth factor reacted on immunoblots with antiserum to human placenta-derived basic FGF and competed with iodinated basic FGF for binding to antiserum to (1-24)bFGF synthetic peptide. To confirm that fibroblasts were the source of the growth factor, cell lysates were prepared from cells incubated with radiolabeled methionine. Heparin affinity purified material was immunoprecipitated with basic FGF antiserum and electrophoresed. Radiolabeled material was detected on gel autoradiographs in the same molecular weight region as authentic iodinated basic FGF. The findings are consistant with the notion that cultured fibroblasts express basic FGF. As these cells also respond to the mitogen, it is possible that the regulation of their growth is under autocrine control. Fibroblasts may be an important source of the growth factor in tissue

  19. Phosphorylation of mitogen-activated protein kinase (MAPK) is required for cytokinesis and progression of cell cycle in tobacco BY-2 cells.

    Ma, Zhaowu; Yu, Guanghui

    2010-02-15

    The role of mitogen-activated protein kinase (MAPK) in plant cytokinesis remains largely uncharacterized. To elucidate its role, tobacco Bright Yellow-2 (BY-2) cells have been synchronized using a two-step procedure, and the different phases of the cell cycle identified by Histone 4 gene expression and the mitotic index. MAPK expression was analyzed by semi-quantitative (SQ) RT-PCR and protein gel blot analysis for phosphorylated MAPK during cell cycle progression. The SQ RT-PCR analysis indicated that MAPK expression is lower in mitosis than in interphase (G1, G2 and S). However, the amount of phosphorylated MAPK remained stable throughout the cell cycle, indicating that MAPK activity is predominantly regulated at the post-translational level and that phosphorylation of MAPK plays an important role in mitosis. Application of the specific MAPK phosphorylation inhibitor U0126 revealed that while U0126 treatment decreases the phosphorylation of MAPK and the progression from telophase to early cytokinesis is significantly inhibited. The formation of the phragmoplast is also negatively affected at this stage. These results demonstrate that MAPK phosphorylation is involved in the formation of the cell plate within the phragmoplast during cytokinesis and that MAPK predominantly functions during the cytokinesis stage of the cell cycle in tobacco BY-2 cells. Copyright 2009 Elsevier GmbH. All rights reserved.

  20. Moringa oleifera fruit induce apoptosis via reactive oxygen species-dependent activation of mitogen-activated protein kinases in human melanoma A2058 cells.

    Guon, Tae Eun; Chung, Ha Sook

    2017-08-01

    The present study was performed to determine the effect of Moringa oleifera fruit extract on the apoptosis of human melanoma A2058 cells. A2058 cells were treated for 72 h with Moringa oleifera fruit extract at 50-100 µg/ml, and cell viability with apoptotic changes was examined. The involvement of reactive oxygen species (ROS) and mitogen-activated protein kinases (MAPKs) was examined. It was revealed that Moringa oleifera fruit extract significantly inhibited the cell viability and promoted apoptosis of A2058 cells in a concentration-dependent manner. Moringa oleifera fruit extract-treated A2058 cells exhibited increased activities of cleaved caspase-9 and caspase-3. It also caused an enhancement of MAPK phosphorylation and ROS production. The pro-apoptotic activity of Moringa oleifera fruit extract was significantly reversed by pretreatment with the c-Jun N-terminal kinase (JNK) inhibitor SP600125, extracellular-signal-regulated kinase (ERK) inhibitor PD98058 or ROS inhibitor N-acetyl-L-cysteine. Taken together, Moringa oleifera fruit extract is effective in inducing mitochondrial apoptosis of A2058 cells, which is mediated through induction of ROS formation, and JNK and ERK activation. Moringa oleifera fruit extract may thus have therapeutic benefits for human melanoma A2058 cells.

  1. Expression of the Grb2-related protein of the lymphoid system in B cell subsets enhances B cell antigen receptor signaling through mitogen-activated protein kinase pathways.

    Yankee, Thomas M; Solow, Sasha A; Draves, Kevin D; Clark, Edward A

    2003-01-01

    Adapter proteins play a critical role in regulating signals triggered by Ag receptor cross-linking. These small molecules link receptor proximal events with downstream signaling pathways. In this study, we explore the expression and function of the Grb2-related protein of the lymphoid system (GrpL)/Grb2-related adaptor downstream of Shc adapter protein in human B cells. GrpL is expressed in naive B cells and is down-regulated following B cell Ag receptor ligation. By contrast, germinal center and memory B cells express little or no GrpL. Using human B cell lines, we detected constitutive interactions between GrpL and B cell linker protein, Src homology (SH)2 domain-containing leukocyte protein of 76 kDa, hemopoietic progenitor kinase 1, and c-Cbl. The N-terminal SH3 domain of GrpL binds c-Cbl while the C-terminal SH3 domain binds B cell linker protein and SH2 domain-containing leukocyte protein of 76 kDa. Exogenous expression of GrpL in a GrpL-negative B cell line leads to enhanced Ag receptor-induced extracellular signal-related kinase and p38 mitogen-activated protein kinase phosphorylation. Thus, GrpL expression in human B cell subsets appears to regulate Ag receptor-mediated signaling events.

  2. Aqueous fraction from Cuscuta japonica seed suppresses melanin synthesis through inhibition of the p38 mitogen-activated protein kinase signaling pathway in B16F10 cells.

    Jang, Ji Yeon; Kim, Ha Neui; Kim, Yu Ri; Choi, Yung Hyun; Kim, Byung Woo; Shin, Hwa Kyoung; Choi, Byung Tae

    2012-05-07

    Semen cuscutae has been used traditionally to treat pimples and alleviate freckles and melasma in Korea. The present study aimed to investigate the inhibitory effect of Cuscuta japonica Choisy seeds on alpha-melanocyte-stimulating hormone (α-MSH)-induced melanogenesis. The aqueous fraction from Semen cuscutae (AFSC) was used to determine anti-melanogenic effects by examination of cellular melanin contents, tyrosinase activity assay, cAMP assay and Western blot analysis for melanin synthesis-related signaling proteins in B16F10 mouse melanoma cells. AFSC markedly inhibited α-MSH-induced melanin synthesis and tyrosinase activity, and also decreased α-MSH-induced expression of microphthalmia-associated transcription factor (MITF) and tyrosinase-related proteins (TRPs). Moreover, AFSC significantly decreased the level of phosphorylated p38 mitogen-activated protein kinase (MAPK) signaling through the down-regulation of α-MSH-induced cAMP. Furthermore, we confirmed that the specific inhibitor of p38 MAPK (SB203580)-mediated suppressed melanin synthesis and tyrosinase activity was further attenuated by AFSC. AFSC also further decreased SB203580-mediated suppression of MITF and TRP expression. These results indicate that AFSC inhibits p38 MAPK phosphorylation with suppressed cAMP levels and subsequently down-regulate MITF and TRP expression, which results in a marked reduction of melanin synthesis and tyrosinase activity in α-MSH-stimulated B16F10 cells. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  3. Inhibition of gap-junctional intercellular communication and activation of mitogen-activated protein kinases by cyanobacterial extracts--indications of novel tumor-promoting cyanotoxins?

    Bláha, Ludĕk; Babica, Pavel; Hilscherová, Klára; Upham, Brad L

    2010-01-01

    Toxicity and liver tumor promotion of cyanotoxins microcystins have been extensively studied. However, recent studies document that other metabolites present in the complex cyanobacterial water blooms may also have adverse health effects. In this study we used rat liver epithelial stem-like cells (WB-F344) to examine the effects of cyanobacterial extracts on two established markers of tumor promotion, inhibition of gap-junctional intercellular communication (GJIC) and activation of mitogen-activated protein kinases (MAPKs) - ERK1/2. Extracts of cyanobacteria (laboratory cultures of Microcystis aeruginosa and Aphanizomenon flos-aquae and water blooms dominated by these species) inhibited GJIC and activated MAPKs in a dose-dependent manner (effective concentrations ranging 0.5-5mgd.w./mL). Effects were independent of the microcystin content and the strongest responses were elicited by the extracts of Aphanizomenon sp. Neither pure microcystin-LR nor cylindrospermopsin inhibited GJIC or activated MAPKs. Modulations of GJIC and MAPKs appeared to be specific to cyanobacterial extracts since extracts from green alga Chlamydomonas reinhardtii, heterotrophic bacterium Klebsiella terrigena, and isolated bacterial lipopolysaccharides had no comparable effects. Our study provides the first evidence on the existence of unknown cyanobacterial toxic metabolites that affect in vitro biomarkers of tumor promotion, i.e. inhibition of GJIC and activation of MAPKs.

  4. Receptor trafficking via the perinuclear recycling compartment accompanied by cell division is necessary for permanent neurotensin cell sensitization and leads to chronic mitogen-activated protein kinase activation.

    Toy-Miou-Leong, Mireille; Cortes, Catherine Llorens; Beaudet, Alain; Rostène, William; Forgez, Patricia

    2004-03-26

    Most G protein-coupled receptors are internalized after interaction with their respective ligand, a process that subsequently contributes to cell desensitization, receptor endocytosis, trafficking, and finally cell resensitization. Although cellular mechanisms leading to cell desensitization have been widely studied, those responsible for cell resensitization are still poorly understood. We examined here the traffic of the high affinity neurotensin receptor (NT1 receptor) following prolonged exposure to high agonist concentration. Fluorescence and confocal microscopy of Chinese hamster ovary, human neuroblastoma (CHP 212), and murine neuroblastoma (N1E-115) cells expressing green fluorescent protein-tagged NT1 receptor revealed that under prolonged treatment with saturating concentrations of neurotensin (NT) agonist, NT1 receptor and NT transiently accumulated in the perinuclear recycling compartment (PNRC). During this cellular event, cell surface receptors remained markedly depleted as detected by both confocal microscopy and (125)I-NT binding assays. In dividing cells, we observed that following prolonged NT agonist stimulation, NT1 receptors were removed from the PNRC, accumulated in dispersed vesicles inside the cytoplasm, and subsequently reappeared at the cell surface. This NT binding recovery allowed for constant cell sensitization and led to a chronic activation of mitogen-activated protein kinases p42 and p44. Under these conditions, the constant activation of NT1 receptor generates an oncogenic regulation. These observations support the potent role for neuropeptides, such as NT, in cancer progression.

  5. Buddleja officinalis suppresses high glucose-induced vascular smooth muscle cell proliferation: role of mitogen-activated protein kinases, nuclear factor-kappaB and matrix metalloproteinases.

    Lee, Yun Jung; Kim, Jin Sook; Kang, Dae Gill; Lee, Ho Sub

    2010-02-01

    Diabetes mellitus is a well-established risk factor for vascular diseases caused by atherosclerosis. In the development of diabetic atherogenesis, vascular smooth muscle cell proliferation is recognized as a key event. Thus, we aimed to investigate whether an ethanol extract of Buddleja officinalis (EBO) suppresses high glucose-induced proliferation in primary cultured human aortic smooth muscle cells (HASMC). [(3)H]-thymidine incorporation revealed that incubation of HASMC with a high concentration of glucose (25 mmol/L) increased cell proliferation. The expression levels of cell cycle protein were also increased by treatment with high glucose concentration. Pretreatment of HASMC with EBO significantly attenuated the increase of high glucose-induced cell proliferation as well as p38 mitogen-activated protein kinases (MAPK) and JNK phosphorylation. EBO suppressed high glucose-induced matrix metalloproteinase (MMP)-9 activity in a dose-dependent manner. In addition, EBO suppressed nuclear factor-kappaB (NF-kappaB) nuclear translocation and transcriptional activity in high glucose conditions. Taken together, the present data suggest that EBO could suppress high glucose-induced atherosclerotic processes through inhibition of p38, JNK, NF-kappaB and MMP signal pathways in HASMC.

  6. Effects of Butyltins (BTs) on Mitogen-Activated-Protein Kinase Kinase Kinase (MAP3K) and Ras Activity in Human Natural Killer Cells

    Celada, Lindsay J.; Whalen, Margaret M.

    2013-01-01

    Butyltins (BTs) contaminate the environment and are found in human blood. BTs, tributyltin (TBT) and dibutyltin (DBT), diminish the cytotoxic function and levels of key proteins of human natural killer (NK) cells. NK cells are an initial immune defense against tumors, virally-infected cells and antibody-coated cells and thus critical to human health. The signaling pathways that regulate NK cell functions include mitogen-activated protein kinases (MAPKs). Studies have shown that exposure to BTs leads to the activation of specific MAPKs and MAPK kinases (MAP2Ks) in human NK cells. MAP2K kinases (MAP3Ks) are upstream activators of MAP2Ks, which then activate MAPKs. The current study examined if BT-induced activation of MAP3Ks was responsible for MAP2K and thus, MAPK activation. This study examines the effects of TBT and DBT on the total levels of two MAP3Ks, c-Raf and ASK1, as well as activating and inhibitory phosphorylation sites on these MAP3Ks. In addition, the immediate upstream activator of c-Raf, Ras, was examined for BT-induced alterations. Our results show significant activation of the MAP3K, c-Raf, in human NK cells within 10 minutes of TBT exposure and the MAP3K, ASK1, after one hour exposures to TBT. In addition, our results suggest that both TBT and DBT are impacting the regulation of c-Raf. PMID:24038145

  7. Excessive L-cysteine induces vacuole-like cell death by activating endoplasmic reticulum stress and mitogen-activated protein kinase signaling in intestinal porcine epithelial cells.

    Ji, Yun; Wu, Zhenlong; Dai, Zhaolai; Sun, Kaiji; Zhang, Qing; Wu, Guoyao

    2016-01-01

    High intake of dietary cysteine is extremely toxic to animals and the underlying mechanism remains largely unknown. This study was conducted to test the hypothesis that excessive L-cysteine induces cell death by activating endoplasmic reticulum (ER) stress and mitogen-activated protein kinase (MAPK) signaling in intestinal porcine epithelial cells. Jejunal enterocytes were cultured in the presence of 0-10 mmol/L L-cysteine. Cell viability, morphologic alterations, mRNA levels for genes involved in ER stress, protein abundances for glucose-regulated protein 78, C/EBP homologous protein (CHOP), alpha subunit of eukaryotic initiation factor-2 (eIF2α), extracellular signal-regulated kinase (ERK1/2), p38 MAPK, and c-Jun N-terminal protein kinase (JNK1/2) were determined. The results showed that L-cysteine (5-10 mmol/L) reduced cell viability (P L-cysteine were not affected by the autophagy inhibitor 3-methyladenine. The protein abundances for CHOP, phosphorylated (p)-eIF2α, p-JNK1/2, p-p38 MAPK, and the spliced form of XBP-1 mRNA were enhanced (P L-cysteine induces vacuole-like cell death via the activation of ER stress and MAPK signaling in small intestinal epithelial cells. These signaling pathways may be potential targets for developing effective strategies to prevent the toxicity of dietary cysteine.

  8. The Role of Unfolded Protein Response and Mitogen-Activated Protein Kinase Signaling in Neurodegenerative Diseases with Special Focus on Prion Diseases

    Lifeng Yang

    2017-05-01

    Full Text Available Prion diseases are neurodegenerative pathologies characterized by the accumulation of a protease-resistant form of the cellular prion protein named prion protein scrapie (PrPSc in the brain. PrPSc accumulation in the endoplasmic reticulum (ER result in a dysregulated calcium (Ca2+ homeostasis and subsequent initiation of unfolded protein response (UPR leading to neuronal dysfunction and apoptosis. The molecular mechanisms for the transition between adaptation to ER stress and ER stress-induced apoptosis are still unclear. Mitogen-activated protein kinases (MAPKs are serine/threonine protein kinases that rule the signaling of many extracellular stimuli from plasma membrane to the nucleus. However the identification of numerous points of cross talk between the UPR and MAPK signaling pathways may contribute to our understanding of the consequences of ER stress in prion diseases. Indeed the MAPK signaling network is known to regulate cell cycle progression and cell survival or death responses following a variety of stresses including misfolded protein response stress. In this article, we review the UPR signaling in prion diseases and discuss the triad of MAPK signaling pathways. We also describe the role played by MAPK signaling cascades in Alzheimer’s (AD and Parkinson’s disease (PD. We will also overview the mechanisms of cell death and the role of MAPK signaling in prion disease progression and highlight potential avenues for therapeutic intervention.

  9. Comparison of gene expression of mitogenic kinin path in adherent and non-adherent CD 34-stem cells using oligonucleotide microarrays.

    Krzysztof Machaj

    2008-02-01

    Full Text Available One of the more interesting cells present in the umbilical cord blood - as far as their potential clinical use is concerned - are stem cells not presenting the CD34 antigen. These are the pluripotential cells with their biological properties similar to mesenchymal stem cells, with the ability to differentiate into such tissue types as bone, cartilage, nervous (to some extent, glia and muscle. The authors compared the activity of genes coding the proteins in mitogenic signal paths activated by kinin receptors using oligonucleotide microarrays in adherent and non-adherent CD 34- cells derived from umbilical cord blood. In the linear regression model with a 95% prognosis area for differentiating genes outside this area, the following genes were selected: c-jun (present in 3 isoforms and c-fos. The fos and jun genes create the AP-1 transcriptive factor which regulates the expression of genes taking part in numerous cellular processes, including the cell cycle and mitosis. The obtained results shed some light on the molecular processes behind the MSC proliferation and are a starting point for further studies on the mesenchymal stem cell biology.

  10. Effect of Vibrio cholerae neuraminidase on the mitogen response of T lymphocytes. I. Enhancement of macrophage T-lymphocyte cooperation in concanavalin-A-induced lymphocyte activation.

    Knop, J

    1980-12-01

    Vibrio cholerae neuraminidase (VCN) enhances the immune response of lymphocytes in various systems, such as antigen- and mitogen-induced blastogenesis, mixed lymphocyte culture (MLC) and tumor-cell response. We used macrophage-depleted and reconstituted murine lymph-node T-cells to investigate the effect of VCN on macrophage-T-lymphocyte co-operation in Con-A-induced lymphocyte activation. In unfractionated lymph-node cells VCN enhanced the Con-A-induced lymphocyte activation as measured by 3H-thymidine (3H-dThd) incorporation. Removing macrophages from the cells resulted in a significantly diminished response. In addition the enhancing effect of VCN was greatly reduced. Reconstitution of the lymphocyte cultures with macrophages in increasing numbers and from various sources rstored the lymphocyte response and the enhancing effect of VCN. VCN proved to be most efficient in cultures reconstituted with normal peritoneal macrophages. Some effect was also observed using bone-marrow-derived (BM) macrophages. However, higher numbers of normal PE macrophages in the presence of VCN inhibited lymphocyte activation, and inhibition by thioglycollate-broth-induced macrophages was considerably increased by VCN. These results suggest that VCN acts by increasing the efficiency of macrophage-T lymphocyte interaction.

  11. Association analysis between mitogen-activated protein/extracellular signal-regulated kinase (MEK) gene polymorphisms and depressive disorder in the Han Chinese population.

    Hu, Yingyan; Hong, Wu; Smith, Alicia; Yu, Shunying; Li, Zezhi; Wang, Dongxiang; Yuan, Chengmei; Cao, Lan; Wu, Zhiguo; Huang, Jia; Fralick, Drew; Phillips, Michael Robert; Fang, Yiru

    2017-11-01

    Recent research findings suggest that BDNF and BDNF signaling pathways participate in the development of major depressive disorder. Mitogen-activated extracellular signal-regulated kinase (MEK) is the most important kinase in the extracellular signal-regulated kinase pathway, and the extracellular signal-regulated kinase pathway is the key signaling pathway of BDNF, so it may play a role in development of depressive disorder. The aim of this study is to investigate the association between polymorphisms of the MAP2K1 (also known as MEK) gene and depressive disorder. Three single nucleotide polymorphisms (SNPs), were significantly associated with depressive disorder: rs1549854 (p = 0.006), rs1432441 (p = 0.025), and rs7182853 (p = 0.039). When subdividing the sample by gender, two of the SNPs remained statistically associated with depressive disorder in females: rs1549854 (p = 0.013) and rs1432441 (p = 0.04). The rs1549854 and rs1432441 polymorphisms of the MAP2K1 gene may be associated with major depressive disorder, especially in females. This study is the first to report that the MAP2K1 gene may be a genetic marker for depressive disorder. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Fisetin Ameliorated Photodamage by Suppressing the Mitogen-Activated Protein Kinase/Matrix Metalloproteinase Pathway and Nuclear Factor-κB Pathways.

    Chiang, Hsiu-Mei; Chan, Shih-Yun; Chu, Yin; Wen, Kuo-Ching

    2015-05-13

    Ultraviolet (UV) irradiation is one of the most important extrinsic factors contributing to skin photodamage. After UV irradiation, a series of signal transductions in the skin will be activated, leading to inflammatory response and photoaged skin. In this study, fisetin, a flavonol that exists in fruits and vegetables, was investigated for its photoprotective effects. The results revealed that 5-25 μM fisetin inhibits cyclooxygenase-2 (COX-2) and matrix metalloproteinase (MMP)-1, MMP-3, MMP-9 expression induced by ultraviolet B (UVB) irradiation in human skin fibroblasts. In addition, fisetin suppressed UVB-induced collagen degradation. With regard to its effect on upper-stream signal transduction, we found that fisetin reduced the expression of ultraviolet (UV)-induced ERK, JNK, and p38 phosphorylation in the mitogen-activated protein kinase (MAP kinase) pathway. Furthermore, fisetin reduced inhibitor κB (IκB) degradation and increased the amount of p65, which is a major subunit of nuclear factor-κB (NF-κB), in cytoplasm. It also suppressed NF-κB translocated to the nucleus and inhibited cAMP response element-binding protein (CREB) Ser-133 phosphorylation level in the phosphoinositide 3-kinase/protein kinase B/CREB (PI3K/AKT/CREB) pathway. Finally, fisetin inhibited UV-induced intracellular reactive oxygen species (ROS), prostaglandin E2 (PGE2), and nitric oxide (NO) generation. The mentioned effects and mechanisms suggest that fisetin can be used in the development of photoprotective agents.

  13. Protection of Human Podocytes from Shiga Toxin 2-Induced Phosphorylation of Mitogen-Activated Protein Kinases and Apoptosis by Human Serum Amyloid P Component

    Dettmar, Anne K.; Binder, Elisabeth; Greiner, Friederike R.; Liebau, Max C.; Kurschat, Christine E.; Jungraithmayr, Therese C.; Saleem, Moin A.; Schmitt, Claus-Peter; Feifel, Elisabeth; Orth-Höller, Dorothea; Kemper, Markus J.; Pepys, Mark; Würzner, Reinhard

    2014-01-01

    Hemolytic uremic syndrome (HUS) is mainly induced by Shiga toxin 2 (Stx2)-producing Escherichia coli. Proteinuria can occur in the early phase of the disease, and its persistence determines the renal prognosis. Stx2 may injure podocytes and induce proteinuria. Human serum amyloid P component (SAP), a member of the pentraxin family, has been shown to protect against Stx2-induced lethality in mice in vivo, presumably by specific binding to the toxin. We therefore tested the hypothesis that SAP can protect against Stx2-induced injury of human podocytes. To elucidate the mechanisms underlying podocyte injury in HUS-associated proteinuria, we assessed Stx2-induced activation of mitogen-activated protein kinases (MAPKs) and apoptosis in immortalized human podocytes and evaluated the impact of SAP on Stx2-induced damage. Human podocytes express Stx2-binding globotriaosylceramide 3. Stx2 applied to cultured podocytes was internalized and then activated p38α MAPK and c-Jun N-terminal kinase (JNK), important signaling steps in cell differentiation and apoptosis. Stx2 also activated caspase 3, resulting in an increased level of apoptosis. Coincubation of podocytes with SAP and Stx2 mitigated the effects of Stx2 and induced upregulation of antiapoptotic Bcl2. These data suggest that podocytes are a target of Stx2 and that SAP protects podocytes against Stx2-induced injury. SAP may therefore be a useful therapeutic option. PMID:24566618

  14. A mannose-specific tetrameric lectin with mitogenic and antibacterial activities from the ovary of a teleost, the cobia (Rachycentron canadum).

    Ngai, Patrick H K; Ng, T B

    2007-02-01

    A tetrameric lectin, with hemagglutinating activity toward rabbit erythrocytes and with specificity toward D-mannosamine and D(+)-mannose, was isolated from the ovaries of a teleost, the cobia Rachycentron canadum. The isolation protocol comprised ion exchange chromatography on CM-cellulose and Q-Sepharose, ion exchange chromatography by fast protein liquid chromatography (FPLC) on Mono Q, and finally gel filtration by FPLC on Superose 12. The lectin was adsorbed on all ion exchangers used. It exhibited a molecular mass of 180 kDa in gel filtration on Superose 12 and a single 45-kDa band in sodium dodecyl sulfate-polyacrylamide gel electrophoresis, indicating that it is a tetrameric protein. The hemagglutinating activity of the lectin was stable up to 40 degrees C and between pH 4 and pH 10. All hemagglutinating activity disappeared at 60 degrees C and at pH 1 and pH 13. The hemagglutinating activity was doubled in the presence of 0.1 microM FeCl3. The lectin exerted antibacterial activity against Escherichia coli with 50% inhibition at 250 microg. There was no antifungal activity toward Coprinus comatus, Fusarium oxysporum, Mycosphaerella arachidicola, and Rhizoctonia solani at a dose of 300 microg. The lectin exhibited maximal mitogenic response from mouse splenocytes at a concentration of 14 microM.

  15. Calcium Hydroxide-induced Proliferation, Migration, Osteogenic Differentiation, and Mineralization via the Mitogen-activated Protein Kinase Pathway in Human Dental Pulp Stem Cells.

    Chen, Luoping; Zheng, Lisha; Jiang, Jingyi; Gui, Jinpeng; Zhang, Lingyu; Huang, Yan; Chen, Xiaofang; Ji, Jing; Fan, Yubo

    2016-09-01

    Calcium hydroxide has been extensively used as the gold standard for direct pulp capping in clinical dentistry. It induces proliferation, migration, and mineralization in dental pulp stem cells (DPSCs), but the underlying mechanisms are still unclear. The aim of this study was to investigate the role of the mitogen-activated protein (MAP) kinase pathway in calcium hydroxide-induced proliferation, migration, osteogenic differentiation, and mineralization in human DPSCs. Human DPSCs between passages 3 and 6 were used. DPSCs were preincubated with inhibitors of MAP kinases and cultured with calcium hydroxide. The phosphorylated MAP kinases were detected by Western blot analysis. Cell viability was analyzed via the methylthiazol tetrazolium assay. Cell migration was estimated using the wound healing assay. Alkaline phosphatase (ALP) expression was analyzed using the ALP staining assay. Mineralization was studied by alizarin red staining analysis. Calcium hydroxide significantly promoted the phosphorylation of the c-Jun N-terminal kinase (JNK), p38, and extracellular signal-regulated kinase. The inhibition of JNK and p38 signaling abolished calcium hydroxide-induced proliferation of DPSCs. The inhibition of JNK, p38, and extracellular signal-regulated kinase signaling suppressed the migration, ALP expression, and mineralization of DPSCs. Our study showed that the MAP kinase pathway was involved in calcium hydroxide-induced proliferation, migration, osteogenic differentiation, and mineralization in human DPSCs. Copyright © 2016 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  16. Involvement of mitogen-activated protein kinases and NFκB in LPS-induced CD40 expression on human monocytic cells

    Wu Weidong; Alexis, Neil E.; Chen Xian; Bromberg, Philip A.; Peden, David B.

    2008-01-01

    CD40 is a costimulatory molecule linking innate and adaptive immune responses to bacterial stimuli, as well as a critical regulator of functions of other costimulatory molecules. The mechanisms regulating lipopolysaccharide (LPS)-induced CD40 expression have not been adequately characterized in human monocytic cells. In this study we used a human monocytic cell line, THP-1, to investigate the possible mechanisms of CD40 expression following LPS exposure. Exposure to LPS resulted in a dose- and time-dependent increase in CD40 expression. Further studies using immunoblotting and pharmacological inhibitors revealed that mitogen-activated protein kinases (MAPKs) and NFκB were activated by LPS exposure and involved in LPS-induced CD40 expression. Activation of MAPKs was not responsible for LPS-induced NFκB activation. TLR4 was expressed on THP-1 cells and pretreatment of cells with a Toll-like receptor 4 (TLR4) neutralizing antibody (HTA125) significantly blunted LPS-induced MAPK and NFκB activation and ensuing CD40 expression. Additional studies with murine macrophages expressing wild type and mutated TLR4 showed that TLR4 was implicated in LPS-induced ERK and NFκB activation, and CD40 expression. Moreover, blockage of MAPK and NFκB activation inhibited LPS-induced TLR4 expression. In summary, LPS-induced CD40 expression in monocytic cells involves MAPKs and NFκB

  17. Enhancement in irradiated mononuclear cells in culture of mitogen-induced incorporation of [3H]thymidine by homologous conditioned medium

    Sandru, G.; Greiner, R.

    1994-01-01

    Incorporation of [ 3 H]thymidine in irradiated peripheral blood mononuclear cell cultures irradiated in vitro was stimulated significantly by either concanavalin A or phytohemagglutinin only in the presence of homologous conditioned medium. Production of this activity by mononuclear cells was enhanced by irradiation and/or pulsed exposure to puromycin but was abolished by actinomycin D. Addition of anti-interleukin 1 or anti-interleukin 2 monoclonal antibodies to the conditioned medium before assay did not influence the stimulatory action. A similar significant stimulation of mononuclear cell cultures irradiated with 6 Gy by concanavalin A was obtained when purified preparations of homologous conditioned medium were used in the assay. Purification was done by ultrafiltration and concentration, heparin agarose chromatography, ammonium sulfate precipitation, concanavalin A agarose chromatography, DEAE-ion exchange chromatography and HPLC gel filtration chromatography. With SDS-PAGE and silver staining, the active HPLC fraction gave one band of 50 kDa, suggesting that this protein is responsible for the co-stimulatory effect of homologous conditioned medium for both mitogen-induced irradiated and nonirradiated mononuclear cell cultures. 42 refs., 9 figs., 3 tabs

  18. Effect of irradiation on human T-cell proliferation: low dose irradiation stimulates mitogen-induced proliferation and function of the suppressor/cytotoxic T-cell subset

    Gualde, N.; Goodwin, J.S.

    1984-01-01

    Unfractionated human T cells exposed to 10-50 rad of X irradiation incorporated less [ 3 H]thymidine than nonirradiated T cells when subsequently cultured with PHA or Con A. The cytotoxic/suppressor T-cell subset, isolated as either OKT8(+) or OKT4(-) cells, demonstrated significantly enhanced [ 3 H]thymidine incorporation in PHA- or Con A-stimulated cultures after exposure to 10-50 rad, compared to unirradiated cells, while the proliferation of the OKT4(+) helper/inducer subset was inhibited by low dose irradiation. It has been previously reported that approximately 30% of the cytotoxic/suppressor subset also stains with OKM1. When the cytotoxic/suppressor subset was further subdivided into OKT4(-), OKM1(+), and OKT4(-), OKM1(-) cells, proliferation of the OKT4(-), OKM1(+) population was inhibited by exposure to 25 rad while proliferation of the OKT4(-), OKM1(-) population was stimulated. The increase in proliferation of the cytotoxic/suppressor T-cell subset after low dose irradiation is paralleled by an increase in suppressor activity of these cells. T cells exposed to 25 rad and then cultured with Con A for 48 hr caused greater inhibition of IgG production when added to fresh autologous lymphocytes stimulated by pokeweed mitogen than did unirradiated cells. Thus, low dose irradiation enhances both the proliferation and function of the human suppressor T-cell subset

  19. Immunomodulatory Activity of Ganoderma atrum Polysaccharide on Purified T Lymphocytes through Ca2+/CaN and Mitogen-Activated Protein Kinase Pathway Based on RNA Sequencing.

    Xiang, Quan-Dan; Yu, Qiang; Wang, Hui; Zhao, Ming-Ming; Liu, Shi-Yu; Nie, Shao-Ping; Xie, Ming-Yong

    2017-07-05

    Our previous study has demonstrated that Ganoderma atrum polysaccharide (PSG-1) has immunomodulatory activity on spleen lymphocytes. However, how PSG-1 exerts its effect on purified lymphocytes is still obscure. Thus, this study aimed to investigate the immunomodulatory activity of PSG-1 on purified T lymphocytes and further elucidate the underlying mechanism based on RNA sequencing (RNA-seq). Our results showed that PSG-1 promoted T lymphocytes proliferation and increased the production of IL-2, IFN-γ, and IL-12. Meanwhile, RNA-seq analysis found 394 differentially expressed genes. KEGG pathway analysis identified 20 significant canonical pathways and seven biological functions. Furthermore, PSG-1 elevated intracellular Ca 2+ concentration and calcineurin (CaN) activity and raised the p-ERK, p-JNK, and p-p38 expression levels. T lymphocytes proliferation and the production of IL-2, IFN-γ, and IL-12 were decreased by the inhibitors of calcium channel and mitogen-activated protein kinases (MAPKs). These results indicated that PSG-1 possesses immunomodulatory activity on purified T lymphocytes, in which Ca 2+ /CaN and MAPK pathways play essential roles.

  20. Ethanol extract of the seed of Zizyphus jujuba var. spinosa potentiates hippocampal synaptic transmission through mitogen-activated protein kinase, adenylyl cyclase, and protein kinase A pathways.

    Jo, So Yeon; Jung, In Ho; Yi, Jee Hyun; Choi, Tae Joon; Lee, Seungheon; Jung, Ji Wook; Yun, Jeanho; Lee, Young Choon; Ryu, Jong Hoon; Kim, Dong Hyun

    2017-03-22

    As the seed of Zizyphus jujuba var. spinosa (Bunge) Hu ex H.F. Chow (Rhamnaceae) has been used to sleep disturbances in traditional Chinese and Korean medicine, many previous studies have focused on its sedative effect. Recently, we reported the neuroprotective effect of the effect of Z. jujuba var. spinosa. However, its effects on synaptic function have not yet been studied. In this project, we examined the action of ethanol extract of the seed of Z. jujuba var. spinosa (DHP1401) on synaptic transmission in the hippocampus. To investigate the effects of DHP1401, field recordings were conducted using hippocampal slices (400µm). Object recognition test was introduced to examine whether DHP1401 affect normal recognition memory. DHP1401 (50μg/ml) induced a significant increase in synaptic activity in Shaffer collateral pathway in a concentration-dependent manner. This increase of synaptic responses was blocked by NBQX, a broad spectrum α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor antagonist, but not IEM-1460, a Ca 2+ -permeable AMPAR blocker. Moreover, U0126, a mitogen-activated protein kinase inhibitor, SQ22536, an adenylyl cyclase inhibitor, and PKI, a protein kinase A inhibitor, blocked DHP1401-induced increase in synaptic transmission. Finally, DHP1401 facilitated object recognition memory. These results suggest that DHP1401 increase synaptic transmission through increase of synaptic AMPAR transmission via MAPK, AC and PAK. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.

  1. Ibuprofen abates cypermethrin-induced expression of pro-inflammatory mediators and mitogen-activated protein kinases and averts the nigrostriatal dopaminergic neurodegeneration.

    Singh, Ashish; Tripathi, Pratibha; Prakash, Om; Singh, Mahendra Pratap

    2016-12-01

    Cypermethrin induces oxidative stress, microglial activation, inflammation and apoptosis leading to Parkinsonism in rats. While ibuprofen, a non-steroidal anti-inflammatory drug, relieves from inflammation, its efficacy against cypermethrin-induced Parkinsonism has not yet been investigated. The study aimed to explore the protective role of ibuprofen in cypermethrin-induced Parkinsonism, an environmentally relevant model of Parkinson's disease (PD), along with its underlying mechanism. Animals were treated with/without cypermethrin in the presence/absence of ibuprofen. Behavioural, immunohistochemical and biochemical parameters of Parkinsonism and expression of pro-inflammatory and pro-apoptotic proteins along with mitogen-activated protein kinases (MAPKs) were determined. Ibuprofen resisted cypermethrin-induced behavioural impairments, striatal dopamine depletion, oxidative stress in the nigrostriatal tissues and loss of the nigral dopamine producing cells and increase in microglial activation along with atypical expression of pro-inflammatory and apoptotic proteins that include cyclooxygenase-2, tumour necrosis factor-α, MAPKs (c-Jun N-terminal kinase, p38 and extracellular signal-regulated kinase), B cell lymphoma 2-associated protein X, tumour suppressor protein p53, cytochrome c and caspase-3 in the nigrostriatal tissue. The results obtained thus demonstrate that ibuprofen lessens inflammation and regulates MAPKs expression thereby averts cypermethrin-induced Parkinsonism.

  2. The impact of polyphenols on chondrocyte growth and survival: a preliminary report

    Salvador Fernández-Arroyo

    2015-10-01

    Full Text Available Background: Imbalances in the functional binding of fibroblast growth factors (FGFs to their receptors (FGFRs have consequences for cell proliferation and differentiation that in chondrocytes may lead to degraded cartilage. The toxic, proinflammatory, and oxidative response of cytokines and FGFs can be mitigated by dietary polyphenols. Objective: We explored the possible effects of polyphenols in the management of osteoarticular diseases using a model based on the transduction of a mutated human FGFR3 (G380R in murine chondrocytes. This mutation is present in most cases of skeletal dysplasia and is responsible for the overexpression of FGFR3 that, in the presence of its ligand, FGF9, results in toxic effects leading to altered cellular growth. Design: Different combinations of dietary polyphenols derived from plant extracts were assayed in FGFR3 (G380R mutated murine chondrocytes, exploring cell survival, chloride efflux, extracellular matrix (ECM generation, and grade of activation of mitogen-activated protein kinases. Results: Bioactive compounds from Hibiscus sabdariffa reversed the toxic effects of FGF9 and restored normal growth, suggesting a probable translation to clinical requests in humans. Indeed, these compounds activated the intracellular chloride efflux, increased ECM generation, and stimulated cell proliferation. The inhibition of mitogen-activated protein kinase phosphorylation was interpreted as the main mechanism governing these beneficial effects. Conclusions: These findings support the rationale behind the encouragement of the development of drugs that repress the overexpression of FGFRs and suggest the dietary incorporation of supplementary nutrients in the management of degraded cartilage.

  3. Growth Problems

    ... Development Infections Diseases & Conditions Pregnancy & Baby Nutrition & Fitness Emotions & Behavior School & Family Life First Aid & Safety Doctors & ... hypothyroidism is feeling tired or sluggish. A blood test measuring thyroid ... not affect intelligence or brain function. The cause of growth hormone ...

  4. Growth Disorders

    ... the changes your body goes through during puberty. Puberty is the stage of your life when sexual development happens, like breast development and menstrual periods in girls and growth of the penis and testicles in boys. One of the body ...

  5. Role of growth factors in the growth of normal and transformed cells

    Lokeshwar, V.B.

    1989-01-01

    Growth factors play an important role in the growth of normal cells. However, their untimely and/or excess production leads to neoplastic transformation. The role of growth factors in the growth of normal cells was studied by investigating the mechanism of transmodulation of the cell surface EGF receptor number by protamine. Protamine increased the EGF stimulated mitogenic response in Swiss mouse 3T3 cells and A431 cells by increasing the number of functionally active EGF receptors. Protamine also increased EGF receptor number in plasma membranes and solubilized membranes. This was evidenced by an increase in both 125 I-EGF-EGF-receptor complex and EGF stimulated phosphorylation of the EGF receptor. The solubilized EGF receptor was retained on a protamine-agarose gel indicating that protamine might increase EGF receptor number by directly activating cryptic EGF receptors in the plasma membranes. The role of growth factors in neoplastic transformation was studied by investigating the role of the oncogene v-sis in the growth of Simian sarcoma virus (SSV) transformed cells. The product of the oncogene v-sis is 94% homologous to the B chain of PDGF. This study found that (i) v-sis gene product is synthesized as a 32 kDa unglycosylated monomer which is glycosylated, dimerized and proteolytically processed into p36, p72, p68, p58, p44 and p27 mol. wt. species respectively. (ii) p36, p72, p68 and p58 are very likely formed in the endoplasmic reticulum and/or Golgi complex. A fraction of newly synthesized p72, p68 and p58 is degraded intracellularly at a fast rate. (iii) p44 is a secretory product which remains tightly associated with the cell surface. p44 is recaptured by the cells through interaction with cell surface PDGF receptors and degraded into p27. (iv) During long term cultures p44 is extracellularly cleaved into a 27 kDa product

  6. Population growth and economic growth.

    Narayana, D L

    1984-01-01

    This discussion of the issues relating to the problem posed by population explosion in the developing countries and economic growth in the contemporary world covers the following: predictions of economic and social trends; the Malthusian theory of population; the classical or stationary theory of population; the medical triage model; ecological disaster; the Global 2000 study; the limits to growth; critiques of the Limits to Growth model; nonrenewable resources; food and agriculture; population explosion and stabilization; space and ocean colonization; and the limits perspective. The Limits to Growth model, a general equilibrium anti-growth model, is the gloomiest economic model ever constructed. None of the doomsday models, the Malthusian theory, the classical stationary state, the neo-Malthusian medical triage model, the Global 2000 study, are so far reaching in their consequences. The course of events that followed the publication of the "Limits to Growth" in 1972 in the form of 2 oil shocks, food shock, pollution shock, and price shock seemed to bear out formally the gloomy predictions of the thesis with a remarkable speed. The 12 years of economic experience and the knowledge of resource trends postulate that even if the economic pressures visualized by the model are at work they are neither far reaching nor so drastic. Appropriate action can solve them. There are several limitations to the Limits to Growth model. The central theme of the model, which is overshoot and collapse, is unlikely to be the course of events. The model is too aggregative to be realistic. It exaggerates the ecological disaster arising out of the exponential growth of population and industry. The gross underestimation of renewable resources is a basic flaw of the model. The most critical weakness of the model is its gross underestimation of the historical trend of technological progress and the technological possiblities within industry and agriculture. The model does correctly emphasize

  7. Characterization of the growth of murine fibroblasts that express human insulin receptors. I. The effect of insulin in the absence of other growth factors

    Randazzo, P.A.; Morey, V.A.; Polishook, A.K.; Jarett, L.

    1990-01-01

    The effect of insulin on the growth of murine fibroblasts transfected with an expression vector containing human insulin receptor cDNA (NIH 3T3/HIR) and the parental cells (NIH/3T3) was characterized. Insulin in the absence of other mitogens increased the rate of incorporation of thymidine into NIH 3T3/HIR cells with a half-maximal response occurring at an insulin concentration of 35 ng/ml and a maximal response that was equivalent to that elicited by 10% fetal calf serum. The thymidine incorporation rate was increased by 12 h, was maximal at approximately 16 h, and returned to basal rates at 24 h after the addition of insulin. Insulin induced a maximum of 65% of cells to incorporate thymidine. The increased DNA synthesis was accompanied by net growth. Addition of insulin to the NIH 3T3/HIR cells resulted in increased DNA content with a half-maximal response occurring at approximately 30 ng/ml insulin and a maximal response equivalent to that elicited by serum. An increase in cell number detected after the addition of insulin to the NIH 3T3/HIR suggests that the cells had progressed through mitosis. Insulin did not increase the rate of thymidine incorporation, DNA content, or number of the parental NIH 3T3 cells. These data show that insulin, in the absence of a second mitogen, is able to induce NIH 3T3/HIR fibroblasts to traverse the cell cycle

  8. Feedback amplification loop drives malignant growth in epithelial tissues.

    Muzzopappa, Mariana; Murcia, Lada; Milán, Marco

    2017-08-29

    Interactions between cells bearing oncogenic mutations and the surrounding microenvironment, and cooperation between clonally distinct cell populations, can contribute to the growth and malignancy of epithelial tumors. The genetic techniques available in Drosophila have contributed to identify important roles of the TNF-α ligand Eiger and mitogenic molecules in mediating these interactions during the early steps of tumor formation. Here we unravel the existence of a tumor-intrinsic-and microenvironment-independent-self-reinforcement mechanism that drives tumor initiation and growth in an Eiger-independent manner. This mechanism relies on cell interactions between two functionally distinct cell populations, and we present evidence that these cell populations are not necessarily genetically different. Tumor-specific and cell-autonomous activation of the tumorigenic JNK stress-activated pathway drives the expression of secreted signaling molecules and growth factors to delaminating cells, which nonautonomously promote proliferative growth of the partially transformed epithelial tissue. We present evidence that cross-feeding interactions between delaminating and nondelaminating cells increase each other's sizes and that these interactions can explain the unlimited growth potential of these tumors. Our results will open avenues toward our molecular understanding of those social cell interactions with a relevant function in tumor initiation in humans.

  9. Mitogenic Activity of a Water-Soluble Adjuvant (Bu-WSA) Obtained from Bacterionema matruchotii: IV. Synergistic Effects of Bu-WSA on Concanavalin A-Induced Proliferative Response of Human Peripheral Blood Lymphocytes.

    Nitta, Toshimasa; Okumura, Seiichi; Tsushi, Masao; Nakano, Masayasu

    1982-07-01

    Butanol-extracted water-soluble adjuvant (Bu-WSA) obtained from Bacterionema matruchotii was cultured with peripheral blood mononuclear cells (PBM) in the presence of sub- and/or supra-optimal mitogenic concentrations of concanavalin A (Con A). The addition of Bu-WSA resulted in increased tritiated thymidine incorporation above that produced by Con A alone. Bu-WSA by itself is not mitogenic for PBM and in fact produced a decrease in thymidine uptake compared to the control. We investigated the response of subpopulation(s) of PBM to Bu-WSA, Con A and a mixture of Bu-WSA and Con A. Separation of PBM into purified T cells, B cells and macrophages showed that cell-cell cooperation of T cells with B cells or macrophages is necessary for the observed synergistic effect of Bu-WSA with Con A. A marked increase in thymidine incorporation by the mixture of T and B cell populations occurred, while only a small amount of thymidine was incorporated when the B cell population was absent. Mitomycin treatment revealed that the response could be ascribed to the T-cell response with a B-cell helper effect. Moreover, Con A and Bu-WSA appeared to act on the same T cell population. This model may provide unique information about the activation of human peripheral blood T cells compared with the activation of these cells by other mitogens. © owned by Center for Academic Publications Japan (Publisher).

  10. Mitogenic activity of a water-soluble adjuvant (Bu-WSA) obtained from Bacterionema matruchotii. IV. Synergistic effects of Bu-WSA on Concanavalin A-induced proliferative response of human peripheral blood lymphocytes.

    Nitta, T; Okumura, S; Tsushi, M; Nakano, M

    1982-01-01

    Butanol-extracted water-soluble adjuvant (Bu-WSA) obtained from Bacterionema matruchotii was cultured with peripheral blood mononuclear cells (PBM) in the presence of sub- and/or supra-optimal mitogenic concentrations of concanavalin A (Con A). The addition of Bu-WSA resulted in increased tritiated thymidine incorporation above that produced by Con A alone. Bu-WSA by itself is not mitogenic for PBM and in fact produced a decrease in thymidine uptake compared to the control. We investigated the response of subpopulation(s) of PBM to Bu-WSA, Con A and a mixture of Bu-WSA and Con A. Separation of PBM into purified T cells, B cells and macrophages showed that cell-cell cooperation of T cells with B cells or macrophages is necessary for the observed synergistic effect of Bu-WSA with Con A. A marked increase in thymidine incorporation by the mixture of T and B cell populations occurred, while only a small amount of thymidine was incorporated when the B cell population was absent. Mitomycin treatment revealed that the response could be ascribed to the T-cell response with a B-cell helper effect. Moreover, Con A and Bu-WSA appeared to act on the same T cell population. This model may provide unique information about the activation of human peripheral blood T cells compared with the activation of these cells by other mitogens.

  11. Coupling growth-factor engineering with nanotechnology for therapeutic angiogenesis.

    Sinha Roy, Rituparna; Soni, Shivani; Harfouche, Rania; Vasudevan, Pooja R; Holmes, Oliver; de Jonge, Hugo; Rowe, Arthur; Paraskar, Abhimanyu; Hentschel, Dirk M; Chirgadze, Dimitri; Blundell, Tom L; Gherardi, Ermanno; Mashelkar, Raghunath A; Sengupta, Shiladitya

    2010-08-03

    Therapeutic angiogenesis is an emerging paradigm for the management of ischemic pathologies. Proangiogenic Therapy is limited, however, by the current inability to deliver angiogenic factors in a sustained manner at the site of pathology. In this study, we investigated a unique nonglycosylated active fragment of hepatocyte growth factor/scatter factor, 1K1, which acts as a potent angiogenic agent in vitro and in a zebrafish embryo and a murine matrigel implant model. Furthermore, we demonstrate that nanoformulating 1K1 for sustained release temporally alters downstream signaling through the mitogen activated protein kinase pathway, and amplifies the angiogenic outcome. Merging protein engineering and nanotechnology offers exciting possibilities for the treatment of ischemic disease, and furthermore allows the selective targeting of downstream signaling pathways, which translates into discrete phenotypes.

  12. Fibroblast growth factor regulates insulin-like growth factor-binding protein production by vascular smooth muscle cells.

    Ververis, J; Ku, L; Delafontaine, P

    1994-02-01

    Insulin-like growth factor I is an important mitogen for vascular smooth muscle cells, and its effects are regulated by several binding proteins. Western ligand blotting of conditioned medium from rat aortic smooth muscle cells detected a 24 kDa binding protein and a 28 kDa glycosylated variant of this protein, consistent with insulin-like growth factor binding protein-4 by size. Low amounts of a glycosylated 38 to 42 kDa doublet (consistent with binding protein-3) and a 31 kDa non-glycosylated protein also were present. Basic fibroblast growth factor markedly increased secretion of the 24 kDa binding protein and its 28 kDa glycosylated variant. This effect was dose- and time-dependent and was inhibited by co-incubation with cycloheximide. Crosslinking of [125I]-insulin-like growth factor I to cell monolayers revealed no surface-associated binding proteins, either basally or after agonist treatment. Induction of binding protein production by fibroblast growth factor at sites of vascular injury may be important in vascular proliferative responses in vivo.

  13. Excessive growth.

    Narayanaswamy, Vasudha; Rettig, Kenneth R; Bhowmick, Samar K

    2008-09-01

    Tall stature and excessive growth syndrome are a relatively rare concern in pediatric practice. Nevertheless, it is important to identify abnormal accelerated growth patterns in children, which may be the clue in the diagnosis of an underlying disorder. We present a case of pituitary gigantism in a 2 1/2-year-old child and discuss the signs, symptoms, laboratory findings, and the treatment. Brief discussions on the differential diagnosis of excessive growth/tall stature have been outlined. Pituitary gigantism is very rare in the pediatrics age group; however, it is extremely rare in a child that is less than 3 years of age. The nature of pituitary adenoma and treatment options in children with this condition have also been discussed.

  14. Regulation of brain capillary endothelial cells by P2Y receptors coupled to Ca2+, phospholipase C and mitogen-activated protein kinase.

    Albert, J L; Boyle, J P; Roberts, J A; Challiss, R A; Gubby, S E; Boarder, M R

    1997-11-01

    1. The blood-brain barrier is formed by capillary endothelial cells and is regulated by cell-surface receptors, such as the G protein-coupled P2Y receptors for nucleotides. Here we investigated some of the characteristics of control of brain endothelial cells by these receptors, characterizing the phospholipase C and Ca2+ response and investigating the possible involvement of mitogen-activated protein kinases (MAPK). 2. Using an unpassaged primary culture of rat brain capillary endothelial cells we showed that ATP, UTP and 2-methylthio ATP (2MeSATP) give similar and substantial increases in cytosolic Ca2+, with a rapid rise to peak followed by a slower decline towards basal or to a sustained plateau. Removal of extracellular Ca2+ had little effect on the peak Ca2+-response, but resulted in a more rapid decline to basal. There was no response to alpha,beta-MethylATP (alpha,beta MeATP) in these unpassaged cells, but a response to this P2X agonist was seen after a single passage. 3. ATP (log EC50 -5.1+/-0.2) also caused an increase in the total [3H]-inositol (poly)phosphates ([3H]-InsPx) in the presence of lithium with a rank order of agonist potency of ATP=UTP=UDP>ADP, with 2MeSATP and alpha,beta MeATP giving no detectable response. 4. Stimulating the cells with ATP or UTP gave a rapid rise in the level of inositol 1,4,5-trisphosphate (Ins(1,4,5)P3), with a peak at 10 s followed by a decline to a sustained plateau phase. 2MeSATP gave no detectable increase in the level of Ins(1,4,5)P3. 5. None of the nucleotides tested affected basal cyclic AMP, while ATP and ATPgammaS, but not 2MeSATP, stimulated cyclic AMP levels in the presence of 5 microM forskolin. 6. Both UTP and ATP stimulated tyrosine phosphorylation of p42 and p44 mitogen-activated protein kinase (MAPK), while 2MeSATP gave a smaller increase in this index of MAPK activation. By use of a peptide kinase assay, UTP gave a substantial increase in MAPK activity with a concentration-dependency consistent with

  15. Duration of streptozotocin-induced diabetes differentially affects p38-mitogen-activated protein kinase (MAPK phosphorylation in renal and vascular dysfunction

    Gupta Akanksha

    2005-03-01

    Full Text Available Abstract Background In the present study we tested the hypothesis that progression of streptozotocin (STZ-induced diabetes (14-days to 28-days would produce renal and vascular dysfunction that correlate with altered p38- mitogen-activated protein kinase (p38-MAPK phosphorylation in kidneys and thoracic aorta. Methods Male Sprague Dawley rats (350–400 g were randomized into three groups: sham (N = 6, 14-days diabetic (N = 6 and 28-days diabetic rats (N = 6. Diabetes was induced using a single tail vein injection of STZ (60 mg/kg, I.V. on the first day. Rats were monitored for 28 days and food, water intake and plasma glucose levels were noted. At both 14-days and 28-days post diabetes blood samples were collected and kidney cortex, medulla and aorta were harvested from each rat. Results The diabetic rats lost body weight at both 14-days (-10% and 28-days (-13% more significantly as compared to sham (+10% group. Glucose levels were significantly elevated in the diabetic rats at both 14-days and 28-days post-STZ administration. Renal dysfunction as evidenced by renal hypertrophy, increased plasma creatinine concentration and reduced renal blood flow was observed in 14-days and 28-days diabetes. Vascular dysfunction as evidenced by decreased carotid blood flow was observed in 14-days and 28-days diabetes. We observed an up-regulation of inducible nitric oxide synthase (iNOS, prepro endothelin-1 (preproET-1 and phosphorylated p38-MAPK in thoracic aorta and kidney cortex but not in kidney medulla in 28-days diabetes group. Conclusion The study provides evidence that diabetes produces vascular and renal dysfunction with a profound effect on signaling mechanisms at later stage of diabetes.

  16. 17beta-estradiol promotes the odonto/osteogenic differentiation of stem cells from apical papilla via mitogen-activated protein kinase pathway.

    Li, Yao; Yan, Ming; Wang, Zilu; Zheng, Yangyu; Li, Junjun; Ma, Shu; Liu, Genxia; Yu, Jinhua

    2014-11-17

    Estrogen plays an important role in the osteogenic differentiation of mesenchymal stem cells, while stem cells from apical papilla (SCAP) can contribute to the formation of dentin/bone-like tissues. To date, the effects of estrogen on the differentiation of SCAP remain unclear. SCAP was isolated and treated with 10⁻⁷ M 17beta-estradiol (E2). The odonto/osteogenic potency and the involvement of mitogen-activated protein kinase (MAPK) signaling pathway were subsequently investigated by using methyl-thiazolyl-tetrazolium (MTT) assay, and other methods. MTT and flow cytometry results demonstrated that E2 treatment had no effect on the proliferation of SCAP in vitro, while alkaline phosphatase (ALP) assay and alizarin red staining showed that E2 can significantly promote ALP activity and mineralization ability in SCAP. Real-time reverse transcription polymerase chain reaction (RT-PCR) and western blot assay revealed that the odonto/osteogenic markers (ALP, DMP1/DMP1, DSPP/DSP, RUNX2/RUNX2, OSX/OSX and OCN/OCN) were significantly upregulated in E2-treated SCAP. In addition, the expression of phosphor-p38 and phosphor-JNK in these stem cells was enhanced by E2 treatment, as was the expression of the nuclear downstream transcription factors including phosphor-Sp1, phosphor-Elk-1, phosphor-c-Jun and phosphor-c-Fos, indicating the activation of MAPK signaling pathway during the odonto/osteogenic differentiation of E2-treated SCAP. Conversely, the differentiation of E2-treated SCAP was inhibited in the presence of MAPK specific inhibitors. The ondonto/osteogenic differentiation of SCAP is enhanced by 10⁻⁷ M 17beta-estradiol via the activation of MAPK signaling pathway.

  17. Carprofen induction of p75NTR-dependent apoptosis via the p38 mitogen-activated protein kinase pathway in prostate cancer cells.

    Khwaja, Fatima S; Quann, Emily J; Pattabiraman, Nagarajan; Wynne, Shehla; Djakiew, Daniel

    2008-11-01

    The p75 neurotrophin receptor (p75(NTR)) functions as a tumor suppressor in prostate epithelial cells, where its expression declines with progression to malignant cancer. Previously, we showed that treatment with R-flurbiprofen or ibuprofen induced p75(NTR) expression in several prostate cancer cell lines leading to p75(NTR)-mediated decreased survival. Using the 2-phenyl propionic acid moiety of these profens as a pharmacophore, we screened an in silico database of 30 million compounds and identified carprofen as having an order of magnitude greater activity for induction of p75(NTR) levels and inhibition of cell survival. Prostate (PC-3 and DU-145) and bladder (T24) cancer cells were more sensitive to carprofen induction of p75(NTR)-associated loss of survival than breast (MCF-7) and fibroblast (3T3) cells. Transfection of prostate cell lines with a dominant-negative form of p75(NTR) before carprofen treatment partially rescued cell survival, showing a cause-and-effect relationship between carprofen induction of p75(NTR) levels and inhibition of survival. Carprofen induced apoptotic nuclear fragmentation in prostate but not in MCF-7 and 3T3 cells. Furthermore, small interfering RNA knockdown of the p38 mitogen-activated protein kinase (MAPK) protein prevented induction of p75(NTR) by carprofen in both prostate cell lines. Carprofen treatment induced phosphorylation of p38 MAPK as early as within 1 min. Expression of a dominant-negative form of MK2, the kinase downstream of p38 MAPK frequently associated with signaling cascades leading to apoptosis, prevented carprofen induction of the p75(NTR) protein. Collectively, we identify carprofen as a highly potent profen capable of inducing p75(NTR)-dependent apoptosis via the p38 MAPK pathway in prostate cancer cells.

  18. Activation of Extracellular Signal-Regulated Kinase but Not of p38 Mitogen-Activated Protein Kinase Pathways in Lymphocytes Requires Allosteric Activation of SOS

    Jun, Jesse E.; Yang, Ming; Chen, Hang; Chakraborty, Arup K.

    2013-01-01

    Thymocytes convert graded T cell receptor (TCR) signals into positive selection or deletion, and activation of extracellular signal-related kinase (ERK), p38, and Jun N-terminal protein kinase (JNK) mitogen-activated protein kinases (MAPKs) has been postulated to play a discriminatory role. Two families of Ras guanine nucleotide exchange factors (RasGEFs), SOS and RasGRP, activate Ras and the downstream RAF-MEK-ERK pathway. The pathways leading to lymphocyte p38 and JNK activation are less well defined. We previously described how RasGRP alone induces analog Ras-ERK activation while SOS and RasGRP cooperate to establish bimodal ERK activation. Here we employed computational modeling and biochemical experiments with model cell lines and thymocytes to show that TCR-induced ERK activation grows exponentially in thymocytes and that a W729E allosteric pocket mutant, SOS1, can only reconstitute analog ERK signaling. In agreement with RasGRP allosterically priming SOS, exponential ERK activation is severely decreased by pharmacological or genetic perturbation of the phospholipase Cγ (PLCγ)-diacylglycerol-RasGRP1 pathway. In contrast, p38 activation is not sharply thresholded and requires high-level TCR signal input. Rac and p38 activation depends on SOS1 expression but not allosteric activation. Based on computational predictions and experiments exploring whether SOS functions as a RacGEF or adaptor in Rac-p38 activation, we established that the presence of SOS1, but not its enzymatic activity, is critical for p38 activation. PMID:23589333

  19. Xingshentongqiao Decoction Mediates Proliferation, Apoptosis, Orexin-A Receptor and Orexin-B Receptor Messenger Ribonucleic Acid Expression and Represses Mitogen-activated Protein Kinase Signaling

    Yuanli Dong

    2015-01-01

    Full Text Available Background: Hypocretin (HCRT signaling plays an important role in the pathogenesis of narcolepsy and can be significantly influenced by Chinese herbal therapy. Our previous study showed that xingshentongqiao decoction (XSTQ is clinically effective for the treatment of narcolepsy. To determine whether XSTQ improves narcolepsy by modulating HCRT signaling, we investigated its effects on SH-SY5Y cell proliferation, apoptosis, and HCRT receptor 1/2 (orexin receptor 1 [OX1R] and orexin receptor 2 [OX2R] expression. The signaling pathways involved in these processes were also assessed. Methods: The effects of XSTQ on proliferation and apoptosis in SH-SY5Y cells were assessed using cell counting kit-8 and annexin V-fluorescein isothiocyanate assays. OX1R and OX2R expression was assessed by quantitative real-time polymerase chain reaction analysis. Western blotting for mitogen-activated protein kinase (MAPK pathway activation was performed to further assess the signaling mechanism of XSTQ. Results: XSTQ reduced the proliferation and induced apoptosis of SH-SY5Y cells. This effect was accompanied by the upregulation of OX1R and OX2R expression and the reduced phosphorylation of extracellular signal-regulated kinase (Erk 1/2, p38 MAPK and c-Jun N-terminal kinase (JNK. Conclusions: XSTQ inhibits proliferation and induces apoptosis in SH-SY5Y cells. XSTQ also promotes OX1R and OX2R expression. These effects are associated with the repression of the Erk1/2, p38 MAPK, and JNK signaling pathways. These results define a molecular mechanism for XSTQ in regulating HCRT and MAPK activation, which may explain its ability to treat narcolepsy.

  20. Targeting p38 Mitogen-Activated Protein Kinase Signaling Restores Subventricular Zone Neural Stem Cells and Corrects Neuromotor Deficits in Atm Knockout Mouse

    Kim, Jeesun

    2012-01-01

    Ataxia-telangiectasia (A-T) is a progressive degenerative disorder that results in major neurological disability. In A-T patients, necropsy has revealed atrophy of cerebellar cortical layers along with Purkinje and granular cell loss. We have previously identified an oxidative stress-mediated increase in phospho-p38 mitogen-activated protein kinase (MAPK) and the resultant downregulation of Bmi-1 and upregulation of p21 as key components of the mechanism causing defective proliferation of neural stem cells (NSCs) isolated from the subventricular zone (SVZ) of Atm−/− mice. However, the in vivo aspect of alteration in SVZ tissue and the functional significance of p38MAPK activation in NSCs for neuropathogenesis of ATM deficiency remain unknown. Here we show that the NSC population was abnormally decreased in the SVZ of 3-month-old Atm−/− mice; this decrease was accompanied by p38MAPK activation. However, after a 2-month treatment with the p38MAPK inhibitor SB203580, starting at 1 month old, Atm−/− mice showed restoration of normal levels of Bmi-1 and p21 with the rescue of NSC population in the SVZ. In addition, treated Atm−/− mice exhibited more Purkinje cells in the cerebellum. Most importantly, motor coordination of Atm−/− mice was significantly improved in the treatment group. Our results show for the first time in vivo evidence of depleted NSCs in the SVZ of Atm−/− mice and also demonstrate that pharmacologic inhibition of p38MAPK signaling has the potential to treat neurological defects of A-T. This study provides a promising approach targeting the oxidative stress-dependent p38 signaling pathway not only for A-T but also for other neurodegenerative disorders. PMID:23197859

  1. Effects of sustained sleep restriction on mitogen-stimulated cytokines, chemokines and T helper 1/ T helper 2 balance in humans.

    John Axelsson

    Full Text Available BACKGROUND: Recent studies suggest that acute sleep deprivation disrupts cellular immune responses by shifting T helper (Th cell activity towards a Th2 cytokine profile. Since little is known about more long-term effects, we investigated how five days of sleep restriction would affect pro-inflammatory, chemotactic, Th1- and Th2 cytokine secretion. METHODS: Nine healthy males participated in an experimental sleep protocol with two baseline sleep-wake cycles (sleep 23.00-07.00 h followed by 5 days with restricted sleep (03.00-07.00 h. On the second baseline day and on the fifth day with restricted sleep, samples were drawn every third hour for determination of cytokines/chemokines (tumor necrosis factor alpha (TNF-α, interleukin (IL -1β, IL-2, IL-4 and monocyte chemoattractant protein-1 (MCP-1 after in vitro stimulation of whole blood samples with the mitogen phytohemagglutinin (PHA. Also leukocyte numbers, mononuclear cells and cortisol were analysed. RESULTS: 5-days of sleep restriction affected PHA-induced immune responses in several ways. There was a general decrease of IL-2 production (p<.05. A shift in Th1/Th2 cytokine balance was also evident, as determined by a decrease in IL2/IL4 ratio. No other main effects of restricted sleep were shown. Two significant interactions showed that restricted sleep resulted in increased TNF-α and MCP-1 in the late evening and early night hours (p's<.05. In addition, all variables varied across the 24 h day. CONCLUSIONS: 5-days of sleep restriction is characterized by a shift towards Th2 activity (i.e. lower 1L-2/IL-4 ratio which is similar to the effects of acute sleep deprivation and psychological stress. This may have implications for people suffering from conditions characterized by excessive Th2 activity like in allergic disease, such as asthma, for whom restricted sleep could have negative consequences.

  2. Salidroside pretreatment attenuates apoptosis and autophagy during hepatic ischemia–reperfusion injury by inhibiting the mitogen-activated protein kinase pathway in mice

    Feng J

    2017-07-01

    Full Text Available Jiao Feng,1,* Qinghui Zhang,2,* Wenhui Mo,3,* Liwei Wu,1 Sainan Li,1 Jingjing Li,1 Tong Liu,1 Shizan Xu,4 Xiaoming Fan,5 Chuanyong Guo1 1Department of Gastroenterology, Shanghai Tenth People’s Hospital, Tongji University School of Medicine, Shanghai, 2Department of Clinical Laboratory, Kunshan First People’s Hospital Affiliated to Jiangsu University, Kunshan, JiangSu, 3Department of Gastroenterology, Minhang Hospital, Fudan University, Shanghai, 4Department of Gastroenterology, Shanghai Tenth People’s Hospital, School of Clinical Medicine of Nanjing Medical University, Shanghai, 5Department of Gastroenterology, Jinshan Hospital of Fudan University, Jinshan, Shanghai, China *These authors contributed equally to this work Abstract: Ischemia–reperfusion injury (IRI contributes to liver damage in many clinical situations, such as liver resection and liver transplantation. In the present study, we investigated the effects of the antioxidant, anti-inflammatory, and anticancer agent salidroside (Sal on hepatic IRI in mice. The mice were randomly divided into six groups: normal control, Sham, Sal (20 mg/kg, IRI, IRI + Sal (10 mg/kg, and IRI + Sal (20 mg/kg. We measured liver enzymes, proinflammatory cytokines, TNF-α and interleukin-6, and apoptosis- and autophagy-related marker proteins at 2, 8, and 24 hours after reperfusion. Components of mitogen-activated protein kinase (MAPK signaling, including P-38, jun N-terminal kinase (JNK, and extracellular signal-regulated kinase (ERK, were also measured using an MAPK activator anisomycin to deduce their roles in hepatic IRI. Our results show that Sal safely protects hepatocytes from IRI by reducing levels of liver enzymes in the serum. These findings were confirmed by histopathology. We concluded that Sal protects hepatocytes from IRI partly by inhibiting the activation of MAPK signaling, including the phosphorylation of P38, JNK, and ERK. This ameliorates inflammatory reactions, apoptosis, and

  3. Regulation of p53, nuclear factor κB and cyclooxygenase-2 expression by bromelain through targeting mitogen-activated protein kinase pathway in mouse skin

    Kalra, Neetu; Bhui, Kulpreet; Roy, Preeti; Srivastava, Smita; George, Jasmine; Prasad, Sahdeo; Shukla, Yogeshwer

    2008-01-01

    Bromelain is a pharmacologically active compound, present in stems and immature fruits of pineapples (Ananas cosmosus), which has been shown to have anti-edematous, anti-inflammatory, anti-thrombotic and anti-metastatic properties. In the present study, antitumorigenic activity of bromelain was recorded in 7,12-dimethylbenz(a)anthracene (DMBA)-initiated and 12-O-tetradecanoylphorbol-13-acetate (TPA)-promoted 2-stage mouse skin model. Results showed that bromelain application delayed the onset of tumorigenesis and reduced the cumulative number of tumors, tumor volume and the average number of tumors/mouse. To establish a cause and effect relationship, we targeted the proteins involved in the cell death pathway. Bromelain treatment resulted in upregulation of p53 and Bax and subsequent activation of caspase 3 and caspase 9 with concomitant decrease in antiapoptotic protein Bcl-2 in mouse skin. Since persistent induction of cyclooxygenase-2 (Cox-2) is frequently implicated in tumorigenesis and is regulated by nuclear factor-kappa B (NF-κB), we also investigated the effect of bromelain on Cox-2 and NF-κB expression. Results showed that bromelain application significantly inhibited Cox-2 and inactivated NF-κB by blocking phosphorylation and subsequent degradation of IκBα. In addition, bromelain treatment attenuated DMBA-TPA-induced phosphorylation of extracellular signal-regulated protein kinase (ERK1/2), mitogen-activated protein kinase (MAPK) and Akt. Taken together, we conclude that bromelain induces apoptosis-related proteins along with inhibition of NF-κB-driven Cox-2 expression by blocking the MAPK and Akt/protein kinase B signaling in DMBA-TPA-induced mouse skin tumors, which may account for its anti-tumorigenic effects

  4. The p38 mitogen activated protein kinase regulates β-amyloid protein internalization through the α7 nicotinic acetylcholine receptor in mouse brain.

    Ma, Kai-Ge; Lv, Jia; Yang, Wei-Na; Chang, Ke-Wei; Hu, Xiao-Dan; Shi, Li-Li; Zhai, Wan-Ying; Zong, Hang-Fan; Qian, Yi-Hua

    2018-03-01

    Alzheimer's disease (AD) is one of the most devastating neurodegenerative disorders. Intracellular β-amyloid protein (Aβ) is an early event in AD. It induces the formation of amyloid plaques and neuron damage. The α7 nicotinic acetylcholine receptor (α7nAChR) has been suggested to play an important role in Aβ caused cognition. It has high affinity with Aβ and could mediate Aβ internalization in vitro. However, whether in mouse brain the p38 MAPK signaling pathway is involved in the regulation of the α7nAChR mediated Aβ internalization and their role in mitochondria remains little known. Therefore, in this study, we revealed that Aβ is internalized by cholinergic and GABAergic neurons. The internalized Aβ were found deposits in lysosomes/endosomes and mitochondria. Aβ could form Aβ-α7nAChR complex with α7nAChR, activates the p38 mitogen activated protein kinase (MAPK). And the increasing of α7nAChR could in return mediate Aβ internalization in the cortex and hippocampus. In addition, by using the α7nAChR agonist PNU282987, the p38 phosphorylation level decreases, rescues the biochemical changes which are tightly associated with Aβ-induced apoptosis, such as Bcl2/Bax level, cytochrome c (Cyt c) release. Collectively, the p38 MAPK signaling pathway could regulate the α7nAChR-mediated internalization of Aβ. The activation of α7nAChR or the inhibition of p38 MAPK signaling pathway may be a beneficial therapy to AD. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. Specific and differential activation of mitogen-activated protein kinase cascades by unfamiliar taste in the insular cortex of the behaving rat.

    Berman, D E; Hazvi, S; Rosenblum, K; Seger, R; Dudai, Y

    1998-12-01

    Rats were given to drink an unfamiliar taste solution under conditions that result in long-term memory of that taste. The insular cortex, which contains the taste cortex, was then removed and assayed for activation of mitogen-activated protein kinase (MAPK) cascades by using antibodies to the activated forms of various MAPKs. Extracellular responsive kinase 1-2 (ERK1-2) in the cortical homogenate was significantly activated within taste solution, without alteration in the total level of the ERK1-2 proteins. The activity subsided to basal levels within ERK1-2 was not activated when the taste was made familiar. The effect of the unfamiliar taste was specific to the insular cortex. Jun N-terminal kinase 1-2 (JNK1-2) was activated by drinking the taste but with a delayed time course, whereas the activity of Akt kinase and p38MAPK remained unchanged. Elk-1, a member of the ternary complex factor and an ERK/JNK downstream substrate, was activated with a time course similar to that of ERK1-2. Microinjection of a reversible inhibitor of MAPK/ERK kinase into the insular cortex shortly before exposure to the novel taste in a conditioned taste aversion training paradigm attenuated long-term taste aversion memory without significantly affecting short-term memory or the sensory, motor, and motivational faculties required to express long-term taste aversion memory. It was concluded that ERK and JNK are specifically and differentially activated in the insular cortex after exposure to a novel taste, and that this activation is required for consolidation of long-term taste memory.

  6. Hypoxia-induced mitogenic factor (HIMF/FIZZ1/RELM alpha recruits bone marrow-derived cells to the murine pulmonary vasculature.

    Daniel J Angelini

    2010-06-01

    Full Text Available Pulmonary hypertension (PH is a disease of multiple etiologies with several common pathological features, including inflammation and pulmonary vascular remodeling. Recent evidence has suggested a potential role for the recruitment of bone marrow-derived (BMD progenitor cells to this remodeling process. We recently demonstrated that hypoxia-induced mitogenic factor (HIMF/FIZZ1/RELM alpha is chemotactic to murine bone marrow cells in vitro and involved in pulmonary vascular remodeling in vivo.We used a mouse bone marrow transplant model in which lethally irradiated mice were rescued with bone marrow transplanted from green fluorescent protein (GFP(+ transgenic mice to determine the role of HIMF in recruiting BMD cells to the lung vasculature during PH development. Exposure to chronic hypoxia and pulmonary gene transfer of HIMF were used to induce PH. Both models resulted in markedly increased numbers of BMD cells in and around the pulmonary vasculature; in several neomuscularized small (approximately 20 microm capillary-like vessels, an entirely new medial wall was made up of these cells. We found these GFP(+ BMD cells to be positive for stem cell antigen-1 and c-kit, but negative for CD31 and CD34. Several of the GFP(+ cells that localized to the pulmonary vasculature were alpha-smooth muscle actin(+ and localized to the media layer of the vessels. This finding suggests that these cells are of mesenchymal origin and differentiate toward myofibroblast and vascular smooth muscle. Structural location in the media of small vessels suggests a functional role in the lung vasculature. To examine a potential mechanism for HIMF-dependent recruitment of mesenchymal stem cells to the pulmonary vasculature, we performed a cell migration assay using cultured human mesenchymal stem cells (HMSCs. The addition of recombinant HIMF induced migration of HMSCs in a phosphoinosotide-3-kinase-dependent manner.These results demonstrate HIMF-dependent recruitment of BMD

  7. Nodularin induces tumor necrosis factor-alpha and mitogen-activated protein kinases (MAPK) and leads to induction of endoplasmic reticulum stress

    Meili, Nicole; Christen, Verena [University of Applied Sciences and Arts Northwestern Switzerland (FHNW), Gründenstrasse 40, CH-4132 Muttenz (Switzerland); Fent, Karl, E-mail: karl.fent@fhnw.ch [University of Applied Sciences and Arts Northwestern Switzerland (FHNW), Gründenstrasse 40, CH-4132 Muttenz (Switzerland); Swiss Federal Institute of Technology Zürich (ETH Zürich), Department of Environmental Systems Science, CH-8092 Zürich (Switzerland)

    2016-06-01

    Nodularin is produced by the cyanobacterium Nodularia spumigena. It is of concern due to hepatotoxicity in humans and animals. Here we investigated unexplored molecular mechanisms by transcription analysis in human liver cells, focusing on induction of pro-inflammatory cytokines, the tumor necrosis factor α (TNF-α), endoplasmic reticulum (ER) stress and components of the activator protein-1 complex in human hepatoma cells (Huh7) exposed to non-cytotoxic (0.1 and 1 μM) and toxic concentrations (5 μM) for 24, 48, and 72 h. Transcripts of TNF-α and ER stress marker genes were strongly induced at 1 and 5 μM at all time-points. TNF-α led to induction of mitogen-activated protein kinases (MAPK), as demonstrated by induction of CJUN and CFOS, which form the AP-1 complex. Human primary liver cells reacted more sensitive than Huh7 cells. They showed higher cytotoxicity and induction of TNF-α and ER stress at 2.5 nM, while HepG2 cells were insensitive up to 10 μM due to low expression of organic anion transporting polypeptides. Furthermore, nodularin led to induction of TNF-α protein, and CCAAT/enhancer-binding protein-homologous (CHOP) protein. Our data indicate that nodularin induces inflammation and ER stress and leads to activation of MAPK in liver cells. All of these activated pathways, which were analysed here for the first time in detail, may contribute to the hepatotoxic, and tumorigenic action of nodularin. - Highlights: • Toxicity of nodularin and its mechanisms of action are poorly understood. • We investigated mechanisms of nodularin toxicity in human liver cell lines and human hepatocytes. • We identified several pathways involved in nodularin toxicity. • Nodularin induces TNF-α, MAPK pathway and ER stress • These activated pathways may contribute to the hepatotoxic and tumorigenic action of nodularin.

  8. Nodularin induces tumor necrosis factor-alpha and mitogen-activated protein kinases (MAPK) and leads to induction of endoplasmic reticulum stress

    Meili, Nicole; Christen, Verena; Fent, Karl

    2016-01-01

    Nodularin is produced by the cyanobacterium Nodularia spumigena. It is of concern due to hepatotoxicity in humans and animals. Here we investigated unexplored molecular mechanisms by transcription analysis in human liver cells, focusing on induction of pro-inflammatory cytokines, the tumor necrosis factor α (TNF-α), endoplasmic reticulum (ER) stress and components of the activator protein-1 complex in human hepatoma cells (Huh7) exposed to non-cytotoxic (0.1 and 1 μM) and toxic concentrations (5 μM) for 24, 48, and 72 h. Transcripts of TNF-α and ER stress marker genes were strongly induced at 1 and 5 μM at all time-points. TNF-α led to induction of mitogen-activated protein kinases (MAPK), as demonstrated by induction of CJUN and CFOS, which form the AP-1 complex. Human primary liver cells reacted more sensitive than Huh7 cells. They showed higher cytotoxicity and induction of TNF-α and ER stress at 2.5 nM, while HepG2 cells were insensitive up to 10 μM due to low expression of organic anion transporting polypeptides. Furthermore, nodularin led to induction of TNF-α protein, and CCAAT/enhancer-binding protein-homologous (CHOP) protein. Our data indicate that nodularin induces inflammation and ER stress and leads to activation of MAPK in liver cells. All of these activated pathways, which were analysed here for the first time in detail, may contribute to the hepatotoxic, and tumorigenic action of nodularin. - Highlights: • Toxicity of nodularin and its mechanisms of action are poorly understood. • We investigated mechanisms of nodularin toxicity in human liver cell lines and human hepatocytes. • We identified several pathways involved in nodularin toxicity. • Nodularin induces TNF-α, MAPK pathway and ER stress • These activated pathways may contribute to the hepatotoxic and tumorigenic action of nodularin.

  9. Neuroprotective effects of ebselen in traumatic brain injury model: involvement of nitric oxide and p38 mitogen-activated protein kinase signalling pathway.

    Wei, Liang; Zhang, Yanfei; Yang, Cheng; Wang, Qi; Zhuang, Zhongwei; Sun, Zhiyang

    2014-02-01

    Previous investigations have found that ebselen is able to treat neurodegenerative diseases caused by radical and acute total cerebral ischaemia. The aim of the present study was to investigate the neuroprotective effects of ebselen in a traumatic brain injury (TBI) model. Ninety Sprague-Dawley rats were randomly divided into five groups (n = 18 in each): (i) sham operation; (ii) an injury model group; (iii) low-dose (3 mg/kg) ebselen-treated group; (iv) a moderate-dose (10 mg/kg) ebselen-treated group; and (v) a high-dose (30 mg/kg) ebselen-treated group. The TBI model was created according using a modified weight-drop model. Neurological severity score (NSS), brain water content and histopathological deficits were assessed as parameters of injury severity. Expression of nitric oxide (NO), inducible NO synthase (iNOS) mRNA, Toll-like receptor (TLR) and phosphorylated (p-) p38 mitogen-activated protein kinase (MAPK) were examined by chemical colorimetry, quantitative polymerase chain reaction and western blotting 24 h after intragastric ebselen administration. Rats in the TBI model group exhibited markedly more severe neurological injury (higher NSS, more brain water content and more histopathological deficits) than those in the sham-operated group. Ebselen treatment significantly ameliorated the neurological injury of TBI rats in a dose-dependent manner. Moreover, ebselen significantly reduced the NO and iNOS mRNA levels and inhibited TLR4 and p-p38 MAPK expression, indicating the involvement of NO and p38 MAPK signalling pathways in the neuroprotection afforded by ebselen. In conclusion, ebselen ameliorated neurological injury, possibly by reducing NO levels and modulating the TLR4-mediated p38 MAPK signalling pathway. Therefore, ebselen may have potential to treat secondary injuries of TBI. © 2013 Wiley Publishing Asia Pty Ltd.

  10. Effects of phorbol ester on mitogen-activated protein kinase kinase activity in wild-type and phorbol ester-resistant EL4 thymoma cells.

    Gause, K C; Homma, M K; Licciardi, K A; Seger, R; Ahn, N G; Peterson, M J; Krebs, E G; Meier, K E

    1993-08-05

    Phorbol ester-sensitive and -resistant EL4 thymoma cell lines differ in their ability to activate mitogen-activated protein kinase (MAPK) in response to phorbol ester. Treatment of wild-type EL4 cells with phorbol ester results in the rapid activations of MAPK and pp90rsk kinase, a substrate for MAPK, while neither kinase is activated in response to phorbol ester in variant EL4 cells. This study examines the activation of MAPK kinase (MAPKK), an activator of MAPK, in wild-type and variant EL4 cells. Phosphorylation of a 40-kDa substrate, identified as MAPK, was observed following in vitro phosphorylation reactions using cytosolic extracts or Mono Q column fractions prepared from phorbol ester-treated wild-type EL4 cells. MAPKK activity coeluted with a portion of the inactive MAPK upon Mono Q anion-exchange chromatography, permitting detection of the MAPKK activity in fractions containing both kinases. This MAPKK activity was present in phorbol ester-treated wild-type cells, but not in phorbol ester-treated variant cells or in untreated wild-type or variant cells. The MAPKK from wild-type cells was able to activate MAPK prepared from either wild-type or variant cells. MAPKK activity could be stimulated in both wildtype and variant EL4 cells in response to treatment of cells with okadaic acid. These results indicate that the failure of variant EL4 cells to activate MAP kinase in response to phorbol ester is due to a failure to activate MAPKK. Therefore, the step that confers phorbol ester resistance to variant EL4 cells lies between the activation of protein kinase C and the activation of MAPKK.

  11. Monosodium iodoacetate-induced joint pain is associated with increased phosphorylation of mitogen activated protein kinases in the rat spinal cord

    Jarvis Michael F

    2011-05-01

    Full Text Available Abstract Background Intra-articular injection of monosodium iodoacetate (MIA in the knee joint of rats disrupts chondrocyte metabolism resulting in cartilage degeneration and subsequent nociceptive behavior that has been described as a model of osteoarthritis (OA pain. Central sensitization through activation of mitogen activated protein kinases (MAPKs is recognized as a pathogenic mechanism in chronic pain. In the present studies, induction of central sensitization as indicated by spinal dorsal horn MAPK activation, specifically ERK and p38 phosphorylation, was assessed in the MIA-OA model. Results Behaviorally, MIA-injected rats displayed reduced hind limb grip force 1, 2, and 3 weeks post-MIA treatment. In the same animals, activation of phospho ERK1/2 was gradually increased, reaching a significant level at post injection week 3. Conversely, phosphorylation of p38 MAPK was enhanced maximally at post injection week 1 and decreased, but remained elevated, thereafter. Double labeling from 3-wk MIA rats demonstrated spinal pERK1/2 expression in neurons, but not glia. In contrast, p-p38 was expressed by microglia and a subpopulation of neurons, but not astrocytes. Additionally, there was increased ipsilateral expression of microglia, but not astrocytes, in 3-wk MIA-OA rats. Consistent with increased MAPK immunoreactivity in the contralateral dorsal horn, mechanical allodynia to the contralateral hind-limb was observed 3-wk following MIA. Finally, intrathecal injection of the MEK1 inhibitor PD98059 blocked both reduced hind-limb grip force and pERK1/2 induction in MIA-OA rats. Conclusion Results of these studies support the role of MAPK activation in the progression and maintenance of central sensitization in the MIA-OA experimental pain model.

  12. The Insulin-like Growth Factor (IGF)-I E-Peptides Modulate Cell Entry of the Mature IGF-I Protein

    Pfeffer, Lindsay A.; Brisson, Becky K.; Lei, Hanqin; Barton, Elisabeth R.

    2009-01-01

    Insulin-like growth factor (IGF)-I is a critical protein for cell development and growth. Alternative splicing of the igf1 gene gives rise to multiple isoforms. In rodents, proIGF-IA and proIGF-IB have different carboxy-terminal extensions called the E-peptides (EA and EB) and upon further posttranslational processing, produce the identical mature IGF-I protein. Rodent EB has been reported to have mitogenic and motogenic effects independent of IGF-I. However, effects of EA or EB on mature IGF...

  13. Vascular endothelial growth factor and its relationship with the dental pulp.

    Grando Mattuella, Leticia; Westphalen Bento, Leticia; de Figueiredo, José Antonio Poli; Nör, Jacques Eduardo; de Araujo, Fernando Borba; Fossati, Anna Christina Medeiros

    2007-05-01

    The dental pulp is a loose connective tissue located within rigid dentinal walls. Therefore, when subjected to a stimulus, the pulpal tissue has little expansion capacity. The defense mechanisms of this tissue include the formation of tertiary dentin as well as the production of signaling molecules that help in the repair. The dentin matrix is rich in growth factors (GFs) that, when diluted and diffused into the pulp tissue, aid the healing process of the dentinopulpar complex. The angiogenic GFs participate in this event. Vascular endothelial growth factor (VEGF), a potent mitogen for endothelial cells, promotes endothelial cell survival and angiogenesis. Among its receptors, VEGFR-2 seems to be the most intimately associated with mitogenic activities, cell migration, vascular permeability, and survival of endothelial cells. This literature review addresses the cell-signaling process that occurs in response to a pulp stimulus up to its transduction in the target cell, describing the VEGF, as well as its characteristics and receptors. The reported studies have correlated the expression of VEGF and its potential functions that may have an impact on several dental specialties, thus indicating that further clinical investigations should be conducted in order to translate the results obtained until this moment primarily in laboratory experiments.

  14. Targeted deletion of hepatocyte Ikkβ confers growth advantages

    Koch, Katherine S.; Maeda, Shin; He, Guobin; Karin, Michael; Leffert, Hyam L.

    2009-01-01

    Mice lacking hepatocyte IKKβ (Ikkβ Δhep ) are defective in TNFα-activation of hepatocellular transcription factor NF-κB, and highly susceptible to hepatotoxicity. Following diethylnitrosamine (DEN) exposure, Ikkβ Δhep mice develop more hepatocellular carcinoma (HCC) than control mice due partly to enhanced DEN-induced hepatocyte death. Here we show that Ikkβ Δhep hepatocytes display growth advantages over normal hepatocytes consisting of precocious PCNA and cyclin D1 expression during liver regeneration (shortened hepatocyte G 0 → G 1 transitions), and enhanced recovery efficiency, cyclin D1 expression and cell proliferation after plating. Ex vivo deletion of Ikkβ also accelerates hepatocyte growth. Ikkβ Δhep hepatocyte proliferative responses show heightened sensitivity to TGFα and TNFα, and heightened expression of fibronectin, collagens I/III, nidogen, β-actin and integrin β1 mRNAs. These findings suggest that altered mitogen signaling and expression of extracellular matrix and its associated components underlie growth advantages. Increased HCC development in Ikkβ Δhep mice may also be caused by growth advantages of surviving Ikkβ-deleted hepatocytes.

  15. The quiescent and mitogen stimulated peripheral blood mononuclear cells after gamma irradiation and their P53, P21 and H2AX expression

    Vilasova, Z.; Vavrova, J.; Sinkorova, Z.; Tichy, A.; Oesterreicher, J.; Rezacova, M.; Zoelzer, F.

    2008-01-01

    The aim of this study was to compare reaction of quiescent and proliferating PHA (mitogenic lectin phytohemagglutinin)-stimulated human peripheral blood mononuclear cells (PBMCs) to γ-irradiation and analyze changes of proteins related to repair if DNA damage and apoptosis, such as γH2A.X, p53 and its phosphorylations on serine 15 and 392, and p21. Protein changes induced by radiation are different in quiescent and stimulated PBMCs. W e analyzed changes in proteins related to DNA damage repair and apoptosis using the western blot method in quiescent and stimulated PBMCs. Western blot technique can detect γH2A.X increase only at later times, when the phosphorylation of H2A.X is related to the onset of apoptosis (24-72 h after irradiation by the dose of 4 Gy). The level of H2A.X phosphorylation increased after stimulation of PBMC by PHA (72 h, 10 μg/ml) and as shown here it was detectable by western blot analysis. The increase in γH2A.X that we detected by western blot 4 h after irradiation of stimulated lymphocytes was dose dependent. It can be concluded that measurement of γH2A.X during the first hours after the irradiation is a good marker of the received dose of radiation. We compared the dynamics of p53 induction after irradiation by IR in both quiescent and stimulated lymphocytes. p53 increase was observed only in stimulated lymphocytes, as was p53 phosphorylation at serines-392 and -15. The increase in the amount of p53 was not dose-dependent 4 h after the irradiation. On the other hand, phosphorylation of p53 at serine-15 analyzed 4 h after the irradiation is dose-dependent over the studied dose range. Despite the fact that p53 was not detected in quiescent lymphocytes and a reaction to irradiation was not observed either, p21 levels increased after irradiation in both quiescent and stimulated lymphocytes in a dose-dependent manner. IR induces phosphorylation of p53 at both serines-15 and -392 in PHA stimulated human lymphocytes. However

  16. [The mRNA expression of mitogen-activated protein kinase signal pathway related genes in the blood of arseniasis patients caused by burning coal].

    Luo, Peng; Zhang, Ai-hua; Xiao, Yun; Pan, Xue-li; Dong, Xue-xin; Huang, Xiao-xin

    2013-09-01

    To detect the mRNA expression of ERK1, ERK2, JNK1 and P38 gene in mitogen-activated protein kinase(MAPK) path way in the arseniasis patients caused by burning coal. 70 arseniasis patients caused by burning coal at Jiaole village XingRen county in December 2006 were selected as case group, and another 30 villagers with similar living habits, matched gender and age, healthy physical condition without history of burning high arsenic coal were selected as control group from 12 km nearby the same village.Silver diethyl dithiocarbamate method (Ag-DDC) was taken to detect the arsenic contents in the environmental media, food, and arsenic level in the urine and hair of arseniasis patients.On the principle of informed consent, the peripheral blood was collected from the patients. The total RNA was extracted with Trizol method and cDNA was reversed from it. The mRNA expression of ERK1, ERK2, JNK1 and P38 gene in MAPK path way were tested by real-time fluorescent quantitative PCR (QT-PCR). A total of 70 cases of arseniasis patients (31 cases of mild, 25 cases of moderate and 14 cases of severe) and 30 cases of control were chosen. The median (quartile) of arsenic contents in the indoor air, outdoor air, coal, chili and corn were 0.079 (0.053-0.117) mg/m(3) ,0.007 (0.002-0.015) mg/m(3) , 93.010 (39.460-211.740) mg/kg, 3.460(0.550-16.760) mg/kg and 1.500(0.300-4.140) mg/kg respectively. They were above the national health standards. The median (quartile) of arsenic contents in the soil, rice and drinking water were separately 12.130(4.230-24.820) mg/kg, 0.650(0.300-0.980) mg/kg and 0.043(0.012-0.089)mg/kg, which were within the national health standards. Compared with the control group ((26.97 ± 9.71)µg/g Cr), arsenic level in the patients' urine ((71.48 ± 22.74)µg/g Cr) increased significantly, the differences were significant (F = 90.38, P coal.

  17. Phosphorylation of Icariin Can Alleviate the Oxidative Stress Caused by the Duck Hepatitis Virus A through Mitogen-Activated Protein Kinases Signaling Pathways

    Wen Xiong

    2017-09-01

    Full Text Available The duck virus hepatitis (DVH caused by the duck hepatitis virus A (DHAV has produced extensive economic losses to the duck industry. The currently licensed commercial vaccine has shown some defects and does not completely prevent the DVH. Accordingly, a new alternative treatment for this disease is urgently needed. Previous studies have shown that icariin (ICA and its phosphorylated derivative (pICA possessed good anti-DHAV effects through direct and indirect antiviral pathways, such as antioxidative stress. But the antioxidant activity showed some differences between ICA and pICA. The aim of this study is to prove that ICA and pICA attenuate oxidative stress caused by DHAV in vitro and in vivo, and to investigate their mechanism of action to explain their differences in antioxidant activities. In vivo, the dynamic deaths, oxidative evaluation indexes and hepatic pathological change scores were detected. When was added the hinokitiol which showed the pro-oxidative effect as an intervention method, pICA still possessed more treatment effect than ICA. The strong correlation between mortality and oxidative stress proves that ICA and pICA alleviate oxidative stress caused by DHAV. This was also demonstrated by the addition of hydrogen peroxide (H2O2 as an intervention method in vitro. pICA can be more effective than ICA to improve duck embryonic hepatocytes (DEHs viability and reduce the virulence of DHAV. The strong correlation between TCID50 and oxidative stress demonstrates that ICA and pICA can achieve anti-DHAV effects by inhibiting oxidative stress. In addition, the superoxide dismutase (SOD and glutathione peroxidase (GSH-Px of ICA and pICA showed significant difference. pICA could significantly inhibit the phosphorylation of p38, extra cellular signal regulated Kinase (ERK 1/2 and c-Jun N-terminal kinase (JNK, which were related to mitogen-activated protein kinases (MAPKs signaling pathways. Ultimately, compared to ICA, pICA exhibited more

  18. 2,2',4,4'-Tetrachlorobiphenyl upregulates cyclooxygenase-2 in HL-60 cells via p38 mitogen-activated protein kinase and NF-κB

    Bezdecny, Steven A.; Karmaus, Peer; Roth, Robert A.; Ganey, Patricia E.

    2007-01-01

    Polychlorinated biphenyls (PCBs) are ubiquitous, persistent environmental contaminants that affect a number of cellular systems, including neutrophils. Among the effects caused by the noncoplanar PCB 2,2',4,4'-tetrachlorobiphenyl (2244-TCB) in granulocytic HL-60 cells are increases in superoxide anion production, activation of phospholipase A 2 with subsequent release of arachidonic acid (AA) and upregulation of the inflammatory gene cyclooxygenase-2 (COX-2). The objective of this study was to determine the signal transduction pathways involved in the upregulation of COX-2 by 2244-TCB. Treatment of HL-60 cells with 2244-TCB led to increased expression of COX-2 mRNA. This increase was prevented by the transcriptional inhibitor actinomycin D in cells pretreated with 2244-TCB for 10 min. The increase in COX-2 mRNA was associated with release of 3 H-AA, phosphorylation of p38 and extracellular signal-regulated kinase (ERK) mitogen-activated protein (MAP) kinases, increased levels of nuclear NF-κB and increased superoxide anion production. Bromoenol lactone, an inhibitor of the calcium-independent phospholipase A 2 , reduced 3 H-AA release but had no effect on COX-2 mRNA, protein or activity. Pretreatment with SB-202190 or SB-203580, inhibitors of the p38 MAP kinase pathway, prevented the 2244-TCB-mediated induction of COX-2 and phosphorylation of p38 and ERK MAP kinases. These inhibitors did not alter 3 H-AA release. Treatment with PD 98059 or U 0126, inhibitors of the MAP/ERK (MEK) pathway, prevented the 2244-TCB-mediated activation of ERK but had no effect on COX-2 induction or p38 phosphorylation. 2244-TCB treatment did not affect c-Jun N-terminal kinase (JNK) phosphorylation. 2244-TCB exposure increased the amount of nuclear NF-κB. This increase was prevented by pretreatment with p38 MAP kinase inhibitors, but not by pretreatment with MEK inhibitors. Pretreatment with inhibitors of NF-κB prevented the 2244-TCB-mediated induction of COX-2 mRNA. 2244-TCB

  19. Type I and Type III Interferons Display Different Dependency on Mitogen-Activated Protein Kinases to Mount an Antiviral State in the Human Gut.

    Pervolaraki, Kalliopi; Stanifer, Megan L; Münchau, Stephanie; Renn, Lynnsey A; Albrecht, Dorothee; Kurzhals, Stefan; Senís, Elena; Grimm, Dirk; Schröder-Braunstein, Jutta; Rabin, Ronald L; Boulant, Steeve

    2017-01-01

    Intestinal epithelial cells (IECs) are constantly exposed to commensal flora and pathogen challenges. How IECs regulate their innate immune response to maintain gut homeostasis remains unclear. Interferons (IFNs) are cytokines produced during infections. While type I IFN receptors are ubiquitously expressed, type III IFN receptors are expressed only on epithelial cells. This epithelium specificity strongly suggests exclusive functions at epithelial surfaces, but the relative roles of type I and III IFNs in the establishment of an antiviral innate immune response in human IECs are not clearly defined. Here, we used mini-gut organoids to define the functions of types I and III IFNs to protect the human gut against viral infection. We show that primary non-transformed human IECs, upon viral challenge, upregulate the expression of both type I and type III IFNs at the transcriptional level but only secrete type III IFN in the supernatant. However, human IECs respond to both type I and type III IFNs by producing IFN-stimulated genes that in turn induce an antiviral state. Using genetic ablation of either type I or type III IFN receptors, we show that either IFN can independently restrict virus infection in human IECs. Importantly, we report, for the first time, differences in the mechanisms by which each IFN establishes the antiviral state. Contrary to type I IFN, the antiviral activity induced by type III IFN is strongly dependent on the mitogen-activated protein kinases signaling pathway, suggesting a pathway used by type III IFNs that non-redundantly contributes to the antiviral state. In conclusion, we demonstrate that human intestinal epithelial cells specifically regulate their innate immune response favoring type III IFN-mediated signaling, which allows for efficient protection against pathogens without producing excessive inflammation. Our results strongly suggest that type III IFN constitutes the frontline of antiviral response in the human gut. We propose that

  20. Nicotine stimulates urokinase-type plasminogen activator receptor expression and cell invasiveness through mitogen-activated protein kinase and reactive oxygen species signaling in ECV304 endothelial cells

    Khoi, Pham Ngoc; Park, Jung Sun; Kim, Nam Ho; Jung, Young Do, E-mail: ydjung@chonnam.ac.kr

    2012-03-01

    Urokinase-type plasminogen activator receptor (uPAR) expression is elevated during inflammation, tissue remodeling and in many human cancers. This study investigated the effect of nicotine, a major alkaloid in tobacco, on uPAR expression and cell invasiveness in ECV304 endothelial cells. Nicotine stimulated uPAR expression in a dose-dependent manner and activated extracellular signal-regulated kinases-1/2 (Erk-1/2), c-Jun amino-terminal kinase (JNK) and p38 mitogen activated protein kinase (MAPK). Specific inhibitors of MEK-1 (PD98059) and JNK (SP600125) inhibited the nicotine-induced uPAR expression, while the p38 MAPK inhibitor SB203580 did not. Expression vectors encoding dominant negative MEK-1 (pMCL-K97M) and JNK (TAM67) also prevented nicotine-induced uPAR promoter activity. The intracellular hydrogen peroxide (H{sub 2}O{sub 2}) content was increased by nicotine treatment. The antioxidant N-acetylcysteine prevented nicotine-activated production of reactive oxygen species (ROS) and uPAR expression. Furthermore, exogenous H{sub 2}O{sub 2} increased uPAR mRNA expression. Deleted and site-directed mutagenesis demonstrated the involvement of the binding sites of transcription factor nuclear factor-kappaB (NF-κB) and activator protein (AP)-1 in the nicotine-induced uPAR expression. Studies with expression vectors encoding mutated NF-κB signaling molecules and AP-1 decoy confirmed that NF-κB and AP-1 were essential for the nicotine-stimulated uPAR expression. MAPK (Erk-1/2 and JNK) and ROS functioned as upstream signaling molecules in the activation of AP-1 and NF-κB, respectively. In addition, ECV304 endothelial cells treated with nicotine displayed markedly enhanced invasiveness, which was partially abrogated by uPAR neutralizing antibodies. The data indicate that nicotine induces uPAR expression via the MAPK/AP-1 and ROS/NF-κB signaling pathways and, in turn, stimulates invasiveness in human ECV304 endothelial cells. -- Highlights: ► Endothelial cells

  1. Mitogen-activated protein kinase kinase 1/2 inhibition and angiotensin II converting inhibition in mice with cardiomyopathy caused by lamin A/C gene mutation

    Muchir, Antoine; Wu, Wei; Sera, Fusako; Homma, Shunichi; Worman, Howard J.

    2014-01-01

    Highlights: • Both ACE and MEK1/2 inhibition are beneficial on cardiac function in Lmna cardiomyopathy. • MEK1/2 inhibitor has beneficial effects beyond ACE inhibition for Lmna cardiomyopathy. • These results provide further preclinical rationale for a clinical trial of a MEK1/2 inhibitor. - Abstract: Background: Mutations in the LMNA gene encoding A-type nuclear lamins can cause dilated cardiomyopathy with or without skeletal muscular dystrophy. Previous studies have shown abnormally increased extracellular signal-regulated kinase 1/2 activity in hearts of Lmna H222P/H222P mice, a small animal model. Inhibition of this abnormal signaling activity with a mitogen-activated protein kinase kinase 1/2 (MEK1/2) inhibitor has beneficial effects on heart function and survival in these mice. However, such treatment has not been examined relative to any standard of care intervention for dilated cardiomyopathy or heart failure. We therefore examined the effects of an angiotensin II converting enzyme (ACE) inhibitor on left ventricular function in Lmna H222P/H222P mice and assessed if adding a MEK1/2 inhibitor would provide added benefit. Methods: Male Lmna H222P/H222P mice were treated with the ACE inhibitor benazepril, the MEK1/2 inhibitor selumetinib or both. Transthoracic echocardiography was used to measure left ventricular diameters and fractional shortening was calculated. Results: Treatment of Lmna H222P/H222P mice with either benazepril or selumetinib started at 8 weeks of age, before the onset of detectable left ventricular dysfunction, lead to statistically significantly increased fractional shortening compared to placebo at 16 weeks of age. There was a trend towards a great value for fractional shortening in the selumetinib-treated mice. When treatment was started at 16 weeks of age, after the onset of left ventricular dysfunction, the addition of selumetinib treatment to benazepril lead to a statistically significant increase in left ventricular fractional

  2. Nitric oxide mediates the indole acetic acid induction activation of a mitogen-activated protein kinase cascade involved in adventitious root development.

    Pagnussat, Gabriela Carolina; Lanteri, María Luciana; Lombardo, María Cristina; Lamattina, Lorenzo

    2004-05-01

    Recently, it was demonstrated that nitric oxide (NO) and cGMP are involved in the auxin response during the adventitious rooting process in cucumber (Cucumis sativus; Pagnussat et al., 2002, 2003). However, not much is known about the complex molecular network operating during the cell proliferation and morphogenesis triggered by auxins and NO in that process. Anatomical studies showed that formation of adventitious root primordia was clearly detected in indole acetic acid (IAA)- and NO-treated cucumber explants, while neither cell proliferation nor differentiation into root primordia could be observed in control explants 3 d after primary root was removed. In order to go further with signal transduction mechanisms that operate during IAA- and NO-induced adventitious root formation, experiments were designed to test the involvement of a mitogen-activated protein kinase (MAPK) cascade in that process. Cucumber explants were treated with the NO-donor sodium nitroprusside (SNP) or with SNP plus the specific NO-scavenger cPTIO. Protein extracts from those explants were assayed for protein kinase (PK) activity by using myelin basic protein (MBP) as substrate in both in vitro and in-gel assays. The activation of a PK of approximately 48 kD could be detected 1 d after NO treatment with a maximal activation after 3 d of treatment. In control explants, a PK activity was detected only after 4 d of treatment. The MBP-kinase activity was also detected in extracts from IAA-treated explants, while no signal was observed in IAA + cPTIO treatments. The PK activity could be inhibited by the cell-permeable MAPK kinase inhibitor PD098059, suggesting that the NO-dependent MBP-kinase activity is a MAPK. Furthermore, when PD098059 was administered to explants treated with SNP or IAA, it produced a delay in root emergence and a dose-dependent reduction in root number. Altogether, our results suggest that a MAPK signaling cascade is activated during the adventitious rooting process

  3. Nicotine stimulates urokinase-type plasminogen activator receptor expression and cell invasiveness through mitogen-activated protein kinase and reactive oxygen species signaling in ECV304 endothelial cells

    Khoi, Pham Ngoc; Park, Jung Sun; Kim, Nam Ho; Jung, Young Do

    2012-01-01

    Urokinase-type plasminogen activator receptor (uPAR) expression is elevated during inflammation, tissue remodeling and in many human cancers. This study investigated the effect of nicotine, a major alkaloid in tobacco, on uPAR expression and cell invasiveness in ECV304 endothelial cells. Nicotine stimulated uPAR expression in a dose-dependent manner and activated extracellular signal-regulated kinases-1/2 (Erk-1/2), c-Jun amino-terminal kinase (JNK) and p38 mitogen activated protein kinase (MAPK). Specific inhibitors of MEK-1 (PD98059) and JNK (SP600125) inhibited the nicotine-induced uPAR expression, while the p38 MAPK inhibitor SB203580 did not. Expression vectors encoding dominant negative MEK-1 (pMCL-K97M) and JNK (TAM67) also prevented nicotine-induced uPAR promoter activity. The intracellular hydrogen peroxide (H 2 O 2 ) content was increased by nicotine treatment. The antioxidant N-acetylcysteine prevented nicotine-activated production of reactive oxygen species (ROS) and uPAR expression. Furthermore, exogenous H 2 O 2 increased uPAR mRNA expression. Deleted and site-directed mutagenesis demonstrated the involvement of the binding sites of transcription factor nuclear factor-kappaB (NF-κB) and activator protein (AP)-1 in the nicotine-induced uPAR expression. Studies with expression vectors encoding mutated NF-κB signaling molecules and AP-1 decoy confirmed that NF-κB and AP-1 were essential for the nicotine-stimulated uPAR expression. MAPK (Erk-1/2 and JNK) and ROS functioned as upstream signaling molecules in the activation of AP-1 and NF-κB, respectively. In addition, ECV304 endothelial cells treated with nicotine displayed markedly enhanced invasiveness, which was partially abrogated by uPAR neutralizing antibodies. The data indicate that nicotine induces uPAR expression via the MAPK/AP-1 and ROS/NF-κB signaling pathways and, in turn, stimulates invasiveness in human ECV304 endothelial cells. -- Highlights: ► Endothelial cells treated with nicotine

  4. A Role for Protein Phosphatase 2A in Regulating p38 Mitogen Activated Protein Kinase Activation and Tumor Necrosis Factor-Alpha Expression during Influenza Virus Infection

    Anna H. Y. Law

    2013-04-01

    Full Text Available Influenza viruses of avian origin continue to pose pandemic threats to human health. Some of the H5N1 and H9N2 virus subtypes induce markedly elevated cytokine levels when compared with the seasonal H1N1 virus. We previously showed that H5N1/97 hyperinduces tumor necrosis factor (TNF-alpha through p38 mitogen activated protein kinase (MAPK. However, the detailed mechanisms of p38MAPK activation and TNF-alpha hyperinduction following influenza virus infections are not known. Negative feedback regulations of cytokine expression play important roles in avoiding overwhelming production of proinflammatory cytokines. Here we hypothesize that protein phosphatases are involved in the regulation of cytokine expressions during influenza virus infection. We investigated the roles of protein phosphatases including MAPK phosphatase-1 (MKP-1 and protein phosphatase type 2A (PP2A in modulating p38MAPK activation and downstream TNF-alpha expressions in primary human monocyte-derived macrophages (PBMac infected with H9N2/G1 or H1N1 influenza virus. We demonstrate that H9N2/G1 virus activated p38MAPK and hyperinduced TNF-alpha production in PBMac when compared with H1N1 virus. H9N2/G1 induced PP2A activity in PBMac and, with the treatment of a PP2A inhibitor, p38MAPK phosphorylation and TNF-alpha production were further increased in the virus-infected macrophages. However, H9N2/G1 did not induce the expression of PP2A indicating that the activation of PP2A is not mediated by p38MAPK in virus-infected PBMac. On the other hand, PP2A may not be the targets of H9N2/G1 in the upstream of p38MAPK signaling pathways since H1N1 also induced PP2A activation in primary macrophages. Our results may provide new insights into the control of cytokine dysregulation.

  5. Bioactive glass induced osteogenic differentiation of human adipose stem cells is dependent on cell attachment mechanism and mitogen-activated protein kinases

    M Ojansivu

    2018-02-01

    Full Text Available Bioactive glasses (BaGs are widely utilised in bone tissue engineering (TE but the molecular response of cells to BaGs is poorly understood. To elucidate the mechanisms of cell attachment to BaGs and BaG-induced early osteogenic differentiation, we cultured human adipose stem cells (hASCs on discs of two silica-based BaGs S53P4 (23.0 Na2O - 20.0 CaO - 4.0 P2O5 - 53.0 SiO2 (wt-% and 1-06 (5.9 Na2O - 12.0 K2O - 5.3 MgO - 22.6 CaO - 4.0 P2O5 - 0.2 B2O3 - 50.0 SiO2 in the absence of osteogenic supplements. Both BaGs induced early osteogenic differentiation by increasing alkaline phosphatase activity (ALP and the expression of osteogenic marker genes RUNX2a and OSTERIX. Based on ALP activity, the slower reacting 1-06 glass was a stronger osteoinducer. Regarding the cell attachment, cells cultured on BaGs had enhanced integrinβ1 and vinculin production, and mature focal adhesions were smaller but more dispersed than on cell culture plastic (polystyrene. Focal adhesion kinase (FAK, extracellular signal-regulated kinase (ERK1/2 and c-Jun N-terminal kinase (JNK-induced c-Jun phosphorylations were upregulated by glass contact. Moreover, the BaG-stimulated osteoinduction was significantly reduced by FAK and mitogen-activated protein kinase (MAPK inhibitors, indicating an important role for FAK and MAPKs in the BaG-induced early osteogenic commitment of hASCs. Upon indirect insert culture, the ions released from the BaG discs could not reproduce the observed cellular changes, which highlighted the role of direct cell-BaG interactions in the osteopotential of BaGs. These findings gave valuable insight into the mechanism of BaG-induced osteogenic differentiation and therefore provided knowledge to aid the future design of new functional biomaterials to meet the increasing demand for clinical bone TE treatments.

  6. Mitogen-activated protein kinase kinase 1/2 inhibition and angiotensin II converting inhibition in mice with cardiomyopathy caused by lamin A/C gene mutation

    Muchir, Antoine, E-mail: a.muchir@institut-myologie.org [Department of Medicine, College of Physicians and Surgeons, Columbia University, New York, NY (United States); Department of Pathology and Cell Biology, College of Physicians and Surgeons, Columbia University, New York, NY (United States); Wu, Wei [Department of Medicine, College of Physicians and Surgeons, Columbia University, New York, NY (United States); Department of Pathology and Cell Biology, College of Physicians and Surgeons, Columbia University, New York, NY (United States); Sera, Fusako; Homma, Shunichi [Department of Medicine, College of Physicians and Surgeons, Columbia University, New York, NY (United States); Worman, Howard J., E-mail: hjw14@columbia.edu [Department of Medicine, College of Physicians and Surgeons, Columbia University, New York, NY (United States); Department of Pathology and Cell Biology, College of Physicians and Surgeons, Columbia University, New York, NY (United States)

    2014-10-03

    Highlights: • Both ACE and MEK1/2 inhibition are beneficial on cardiac function in Lmna cardiomyopathy. • MEK1/2 inhibitor has beneficial effects beyond ACE inhibition for Lmna cardiomyopathy. • These results provide further preclinical rationale for a clinical trial of a MEK1/2 inhibitor. - Abstract: Background: Mutations in the LMNA gene encoding A-type nuclear lamins can cause dilated cardiomyopathy with or without skeletal muscular dystrophy. Previous studies have shown abnormally increased extracellular signal-regulated kinase 1/2 activity in hearts of Lmna{sup H222P/H222P} mice, a small animal model. Inhibition of this abnormal signaling activity with a mitogen-activated protein kinase kinase 1/2 (MEK1/2) inhibitor has beneficial effects on heart function and survival in these mice. However, such treatment has not been examined relative to any standard of care intervention for dilated cardiomyopathy or heart failure. We therefore examined the effects of an angiotensin II converting enzyme (ACE) inhibitor on left ventricular function in Lmna{sup H222P/H222P} mice and assessed if adding a MEK1/2 inhibitor would provide added benefit. Methods: Male Lmna{sup H222P/H222P} mice were treated with the ACE inhibitor benazepril, the MEK1/2 inhibitor selumetinib or both. Transthoracic echocardiography was used to measure left ventricular diameters and fractional shortening was calculated. Results: Treatment of Lmna{sup H222P/H222P} mice with either benazepril or selumetinib started at 8 weeks of age, before the onset of detectable left ventricular dysfunction, lead to statistically significantly increased fractional shortening compared to placebo at 16 weeks of age. There was a trend towards a great value for fractional shortening in the selumetinib-treated mice. When treatment was started at 16 weeks of age, after the onset of left ventricular dysfunction, the addition of selumetinib treatment to benazepril lead to a statistically significant increase in left

  7. Phosphorylation and activation of p42 and p44 mitogen-activated protein kinase are required for the P2 purinoceptor stimulation of endothelial prostacyclin production.

    Patel, V; Brown, C; Goodwin, A; Wilkie, N; Boarder, M R

    1996-11-15

    Extracellular ATP and ADP, released from platelets and other sites stimulate the endothelial production of prostacyclin (PGI2) by acting on G-protein-coupled P2Y2 and P2Y2 purinoceptors, contributing to the maintenance of a non-thrombogenic surface. The mechanism, widely described as being dependent on elevated cytosolic [Ca2+], also requires protein tyrosine phosphorylation. Here we show that activation of both these P2 receptor types leads to the tyrosine phosphorylation and activation of both the p42 and p44 forms of mitogen-activated protein kinase (MAPK). 2-Methylthio-ATP and UTP, selectively activating P2Y1 and P2Y2 purinoceptors respectively, and ATP, a non-selective agonist at these two receptors, stimulate the tyrosine phosphorylation of both p42mapk and p44mapk, as revealed by Western blots with an antiserum specific for the tyrosine-phosphorylated forms of the enzymes. By using separation on Resource Q columns, peptide kinase activity associated with the phosphorylated MAPK enzymes distributes into two peaks, one mainly p42mapk and one mainly p44mapk, both of which are stimulated by ATP with respect to kinase activity and phospho-MAPK immunoreactivity. Stimulation of P2Y1 or P2Y2 purinoceptors leads to a severalfold increase in PGI2 efflux; this was blocked in a dose-dependent manner by the selective MAPK kinase inhibitor PD98059. This drug also blocked the agonist-stimulated increase in phospho-MAPK immunoreactivity for both p42mapk and p44mapk but left the phospholipase C response to P2 agonists essentially unchanged. Olomoucine has been reported to inhibit p44mapk activity. Here we show that in the same concentration range olomoucine inhibits activity in both peaks from the Resource Q column and also the agonist stimulation of 6-keto-PGF1, but has no effect on agonist-stimulated phospho-MAPK immunoreactivity. These results provide direct evidence for the involvement of p42 and p44 MAPK in the PGI2 response of intact endothelial cells: we have shown

  8. EphA2 modulates radiosensitive of hepatocellular carcinoma cells via p38/mitogen-activated protein kinase-mediated signal pathways

    Qiao Jin

    2015-10-01

    Full Text Available This experiment was conducted to investigate the role of EPH receptor A2 (EphA2 in the modulation of radiosensitivity of hepatic cellular cancer (HCC cells and to determine whether p38/mitogen-activated protein kinase (p38MAPK signaling mediated EphA2 function in this respect. The protein expressions of EphA2 and phosphorylated p38MAPK were tested in HCC and normal hepatic tissues. In HCC 97H cells, EphA2 was overexpressed and knocked out by transfection with EphA2 expression vector and EphA2-ShRNA, respectively, prior to cell exposure to low-dose irradiation. Significantly upregulated EphA2 and phosphorylated p38MAPK were observed in HCC tissues, compared with those in normal hepatic tissues. Low-dose irradiation (1 Gy only caused minor damage to HCC 97H cells, as assessed by alterations in cell viability, apoptosis rate, and cell healing capacity (p = 0.072, p = 0.078, and p = 0.069 respectively. However, EphA2 knock-out in HCC 97H cells induced significant reduction in cell viability and cell healing capacity after these cells were subjected to low-dose irradiation. Apoptosis rate underwent dramatic increase (p < 0.01. By contrast, EphA2 overexpression in HCC 97H cells reversed these effects and enhanced cell colony formation rate, thus displaying remarkable attenuation of radiosensitivity of HCC 97H cells. Further, SB203580, a specific inhibitor of p38MAPK, was added to HCC 97H cells over-expressing EphA2. The effect of EphA2 overexpression on the radiosensitivity of HCC 97H cells was abrogated. Thus, the present study indicates that EphA2 have the ability to negatively regulate the radiosensitivity of HCC 97H cells, which mainly depends on 38MAPK-mediated signal pathways.

  9. Proteomics reveal energy metabolism and mitogen-activated protein kinase signal transduction perturbation in human Borna disease virus Hu-H1-infected oligodendroglial cells.

    Liu, X; Yang, Y; Zhao, M; Bode, L; Zhang, L; Pan, J; Lv, L; Zhan, Y; Liu, S; Zhang, L; Wang, X; Huang, R; Zhou, J; Xie, P

    2014-05-30

    Borna disease virus (BDV) is a neurotropic, non-cytolytic RNA virus which replicates in the cell nucleus targeting mainly hippocampal neurons, but also astroglial and oligodendroglial cells in the brain. BDV is associated with a large spectrum of neuropsychiatric pathologies in animals. Its relationship to human neuropsychiatric illness still remains controversial. We could recently demonstrate that human BDV strain Hu-H1 promoted apoptosis and inhibited cell proliferation in a human oligodendroglial cell line (OL cells) whereas laboratory BDV strain V acted contrariwise. Here, differential protein expression between BDV Hu-H1-infected OL cells and non-infected OL cells was assessed through a proteomics approach, using two-dimensional electrophoresis followed by matrix-assisted laser desorption ionization-time of flight tandem mass spectrometry. A total of 63 differential host proteins were identified in BDV Hu-H1-infected OL cells compared to non-infected OL cells. We found that most changes referred to alterations related to the pentose phosphate pathway, glyoxylate and dicarboxylate metabolism, the tricarboxylic acid (TCA) cycle, and glycolysis /gluconeogenesis. By manual querying, two differential proteins were found to be associated with mitogen-activated protein kinase (MAPK) signal transduction. Five key signaling proteins of this pathway (i.e., p-Raf, p-MEK, p-ERK1/2, p-RSK, and p-MSK) were selected for Western blotting validation. p-ERK1/2 and p-RSK were found to be significantly up-regulated, and p-MSK was found to be significantly down-regulated in BDV Hu-H1-infected OL cells compared to non-infected OL cell. Although BDV Hu-H1 constitutively activated the ERK-RSK pathway, host cell proliferation and nuclear translocation of activated pERK in BDV Hu-H1-infected OL cells were impaired. These findings indicate that BDV Hu-H1 infection of human oligodendroglial cells significantly perturbs host energy metabolism, activates the downstream ERK-RSK complex of

  10. Organotypic Cultures of Intervertebral Disc Cells: Responses to Growth Factors and Signaling Pathways Involved

    Harris Pratsinis

    2015-01-01

    Full Text Available Intervertebral disc (IVD degeneration is strongly associated with low back pain, a major cause of disability worldwide. An in-depth understanding of IVD cell physiology is required for the design of novel regenerative therapies. Accordingly, aim of this work was the study of IVD cell responses to mitogenic growth factors in a three-dimensional (3D organotypic milieu, comprising characteristic molecules of IVD’s extracellular matrix. In particular, annulus fibrosus (AF cells were cultured inside collagen type-I gels, while nucleus pulposus (NP cells in chondroitin sulfate A (CSA supplemented collagen gels, and the effects of Platelet-Derived Growth Factor (PDGF, basic Fibroblast Growth Factor (bFGF, and Insulin-Like Growth Factor-I (IGF-I were assessed. All three growth factors stimulated DNA synthesis in both AF and NP 3D cell cultures, with potencies similar to those observed previously in monolayers. CSA supplementation inhibited basal DNA synthesis rates, without affecting the response to growth factors. ERK and Akt were found to be phosphorylated following growth factor stimulation. Blockade of these two signaling pathways using pharmacologic inhibitors significantly, though not completely, inhibited growth factor-induced DNA synthesis. The proposed culture systems may prove useful for further in vitro studies aiming at future interventions for IVD regeneration.

  11. Expression profiles of the immune genes CD4, CD8β, IFNγ, IL-4, IL-6 and IL-10 in mitogen-stimulated koala lymphocytes (Phascolarctos cinereus by qRT-PCR

    Iona E. Maher

    2014-03-01

    Full Text Available Investigation of the immune response of the koala (Phascolarctos cinereus is needed urgently, but has been limited by scarcity of species-specific reagents and methods for this unique and divergent marsupial. Infectious disease is an important threat to wild populations of koalas; the most widespread and important of these is Chlamydial disease, caused by Chlamydia pecorum and Chlamydia pneumoniae. In addition, koala retrovirus (KoRV, which is of 100% prevalence in northern Australia, has been proposed as an important agent of immune suppression that could explain the koala’s susceptibility to disease. The correct balance of T regulatory, T helper 1 (Th1 and Th2 lymphocyte responses are important to an individual’s susceptibility or resistance to chlamydial infection. The ability to study chlamydial or KoRV pathogenesis, effects of environmental stressors on immunity, and the response of koalas to vaccines under development, by examining the koala’s adaptive response to natural infection or in-vitro stimulation, has been limited to date by a paucity of species- specific reagents. In this study we have used cytokine sequences from four marsupial genomes to identify mRNA sequences for key T regulatory, Th1 and Th2 cytokines interleukin 4 (IL-4, interleukin 6 (IL-6, interleukin 10 (IL-10 and interferon gamma (IFNγ along with CD4 and CD8β. The koala sequences used for primer design showed >58% homology with grey short-tailed opossum, >71% with tammar wallaby and 78% with Tasmanian devil amino acid sequences. We report the development of real-time RT-PCR assays to measure the expression of these genes in unstimulated cells and after three common mitogen stimulation protocols (phorbol myristate acetate/ionomycin, phorbol myristate acetate/phytohemagglutinin and concanavalin A. Phorbol myristate acetate/ionomycin was found to be the most effective mitogen to up-regulate the production of IL-4, IL-10 and IFNγ. IL-6 production was not

  12. Expression profiles of the immune genes CD4, CD8β, IFNγ, IL-4, IL-6 and IL-10 in mitogen-stimulated koala lymphocytes (Phascolarctos cinereus) by qRT-PCR.

    Maher, Iona E; Griffith, Joanna E; Lau, Quintin; Reeves, Thomas; Higgins, Damien P

    2014-01-01

    Investigation of the immune response of the koala (Phascolarctos cinereus) is needed urgently, but has been limited by scarcity of species-specific reagents and methods for this unique and divergent marsupial. Infectious disease is an important threat to wild populations of koalas; the most widespread and important of these is Chlamydial disease, caused by Chlamydia pecorum and Chlamydia pneumoniae. In addition, koala retrovirus (KoRV), which is of 100% prevalence in northern Australia, has been proposed as an important agent of immune suppression that could explain the koala's susceptibility to disease. The correct balance of T regulatory, T helper 1 (Th1) and Th2 lymphocyte responses are important to an individual's susceptibility or resistance to chlamydial infection. The ability to study chlamydial or KoRV pathogenesis, effects of environmental stressors on immunity, and the response of koalas to vaccines under development, by examining the koala's adaptive response to natural infection or in-vitro stimulation, has been limited to date by a paucity of species- specific reagents. In this study we have used cytokine sequences from four marsupial genomes to identify mRNA sequences for key T regulatory, Th1 and Th2 cytokines interleukin 4 (IL-4), interleukin 6 (IL-6), interleukin 10 (IL-10) and interferon gamma (IFNγ) along with CD4 and CD8β. The koala sequences used for primer design showed >58% homology with grey short-tailed opossum, >71% with tammar wallaby and 78% with Tasmanian devil amino acid sequences. We report the development of real-time RT-PCR assays to measure the expression of these genes in unstimulated cells and after three common mitogen stimulation protocols (phorbol myristate acetate/ionomycin, phorbol myristate acetate/phytohemagglutinin and concanavalin A). Phorbol myristate acetate/ionomycin was found to be the most effective mitogen to up-regulate the production of IL-4, IL-10 and IFNγ. IL-6 production was not consistently up-regulated by

  13. Hepatocyte growth factor in renal failure: promise and reality.

    Vargas, G A; Hoeflich, A; Jehle, P M

    2000-04-01

    Can science discover some secrets of Greek mythology? In the case of Prometheus, we can now suppose that his amazing hepatic regeneration was caused by a peptide growth factor called hepatocyte growth factor (HGF). Increasing evidence indicates that HGF acts as a multifunctional cytokine on different cell types. This review addresses the molecular mechanisms that are responsible for the pleiotropic effects of HGF. HGF binds with high affinity to its specific tyrosine kinase receptor c-met, thereby stimulating not only cell proliferation and differentiation, but also cell migration and tumorigenesis. The three fundamental principles of medicine-prevention, diagnosis, and therapy-may be benefited by the rational use of HGF. In renal tubular cells, HGF induces mitogenic and morphogenetic responses. In animal models of toxic or ischemic acute renal failure, HGF acts in a renotropic and nephroprotective manner. HGF expression is rapidly up-regulated in the remnant kidney of nephrectomized rats, inducing compensatory growth. In a mouse model of chronic renal disease, HGF inhibits the progression of tubulointerstitial fibrosis and kidney dysfunction. Increased HGF mRNA transcripts were detected in mesenchymal and tubular epithelial cells of rejecting kidney. In transplanted patients, elevated HGF levels may indicate renal rejection. When HGF is considered as a therapeutic agent in human medicine, for example, to stimulate kidney regeneration after acute injury, strategies need to be developed to stimulate cell regeneration and differentiation without an induction of tumorigenesis.

  14. Mitogen-activated protein kinase phosphatase-3 (MKP-3 in the surgical wound is necessary for the resolution of postoperative pain in mice

    Skopelja-Gardner S

    2017-03-01

    Full Text Available Sladjana Skopelja-Gardner,1,* Madhurima Saha,1,* Perla Abigail Alvarado-Vazquez,2 Brenna S Liponis,1 Elena Martinez,1 E Alfonso Romero-Sandoval2 1Department of Anesthesiology, Geisel School of Medicine at Dartmouth, Lebanon, NH, 2Department of Pharmaceutical and Administrative Sciences, Presbyterian College School of Pharmacy, Clinton, SC, USA *These authors contributed equally to this work. Abstract: Mitogen-activated protein kinase (MAPK phosphatase-3 (MKP-3 and its substrates (extracellular signal-regulated kinase [ERK] and p38 play an important role in pathophysiological mechanisms of acute postoperative and chronic neuropathic pain in the spinal cord. This study aimed to understand the role of MKP-3 and its target MAPKs at the site of surgical incision in nociceptive behavior. Wild-type (WT and MKP-3 knockout (KO mice underwent unilateral plantar hind paw incision. Mechanical allodynia was assessed by using von Frey filaments. Peripheral ERK-1/2 and p38 phosphorylation were measured by Western blot. Cell infiltration was determined using hematoxylin and eosin histological staining. Peripheral phosphorylated ERK-1/2 (p-ERK-1/2 inhibition was performed in MKP-3 KO mice. In WT mice, mechanical hypersensitivity was observed on postoperative day 1 (0.69±0.17 g baseline vs 0.13±0.08 g day 1, which resolved normally by postoperative day 12 (0.46±0.08 g, N=6. In MKP-3 KO mice, this hypersensitivity persisted at least 12 days after surgery (0.19±0.06 g; N=6. KO mice displayed higher numbers of infiltrating cells (51.4±6 cells/0.1 mm2 than WT mice (8.7±1.2 cells/0.1 mm2 on postoperative day 1 (vs 5–6 cells/0.1 mm2 at baseline that returned to baseline 12 days after surgery (10–12 cells/0.1 mm2. In WT mice, peripheral p-p38 and p-ERK-1/2 expression increased (5- and 3-fold, respectively on postoperative days 1 and 5, and returned to basal levels 7–12 days after surgery (N=3 per group. Peripheral p-p38 levels in MKP-3 KO mice followed

  15. Characterization of the growth of murine fibroblasts that express human insulin receptors. II. Interaction of insulin with other growth factors

    Randazzo, P.A.; Jarett, L.

    1990-01-01

    The effects of insulin-like growth factor-1 (IGF-1), epidermal growth factor (EGF), platelet-derived growth factor (PDGF), and insulin on DNA synthesis were studied in murine fibroblasts transfected with an expression vector containing human insulin receptor cDNA (NIH 3T3/HIR) and the parental NIH 3T3 cells. In NIH 3T3/HIR cells, individual growth factors in serum-free medium stimulated DNA synthesis with the following relative efficacies: insulin greater than or equal to 10% fetal calf serum greater than PDGF greater than IGF-1 much greater than EGF. In comparison, the relative efficacies of these factors in stimulating DNA synthesis by NIH 3T3 cells were 10% fetal calf serum greater than PDGF greater than EGF much greater than IGF-1 = insulin. In NIH 3T3/HIR cells, EGF was synergistic with 1-10 ng/ml insulin but not with 100 ng/ml insulin or more. Synergy of PDGF or IGF-1 with insulin was not detected. In the parental NIH 3T3 cells, insulin and IGF-1 were found to be synergistic with EGF (1 ng/ml), PDGF (100 ng/ml), and PDGF plus EGF. In NIH 3T3/HIR cells, the lack of interaction of insulin with other growth factors was also observed when the percentage of cells synthesizing DNA was examined. Despite insulin's inducing only 60% of NIH 3T3/HIR cells to incorporate thymidine, addition of PDGF, EGF, or PDGF plus EGF had no further effect. In contrast, combinations of growth factors resulted in 95% of the parental NIH 3T3 cells synthesizing DNA. The independence of insulin-stimulated DNA synthesis from other mitogens in the NIH 3T3/HIR cells is atypical for progression factor-stimulated DNA synthesis and is thought to be partly the result of insulin receptor expression in an inappropriate context or quantity

  16. Increased Functional Half-life of Fibroblast Growth Factor-1 by Recovering a Vestigial Disulfide Bond

    Jihun Lee

    2010-12-01

    Full Text Available The fibroblast growth factor (FGF family of proteins contains an absolutely conserved Cys residue at position 83 that is present as a buried free cysteine. We have previously shown that mutation of the structurally adjacent residue, Ala66, to cysteine results in the formation of a stabilizing disulfide bond in FGF-1. This result suggests that the conserved free cysteine residue at position 83 in the FGF family of proteins represents a vestigial half-cystine. Here, we characterize the functional half-life and mitogenic activity of the oxidized form of the Ala66Cys mutation to identify the effect of the recovered vestigial disulfide bond between Cys83 and Cys66 upon the cellular function of FGF-1. The results show that the mitogenic activity of this mutant is significantly increased and that its functional half-life is greatly extended. These favorable effects are conferred by the formation of a disulfide bond that simultaneously increases thermodynamic stability of the protein and removes a reactive buried thiol at position 83. Recovering this vestigial disulfide by introducing a cysteine at position 66 is a potentially useful protein engineering strategy to improve the functional half-life of other FGF family members.

  17. Integration of growth factor signals at the c-fos serum response element.

    Price, M A; Hill, C; Treisman, R

    1996-04-29

    A transcription factor ternary complex composed of serum response factor (SRF) and a second factor, ternary complex factor (TCF), mediates the response of the c-fos Serum Response Element to growth factors and mitogens. In NIH3T3 fibroblasts, TCF binding is required for transcriptional activation by the SRE in response to activation of the Ras-Raf-ERK pathway. We compared the properties of three members of the TCF family, Elk-1, SAP-1 and SAP-2 (ERP/NET). Although all the proteins contain sequences required for ternary complex formation with SRF, only Elk-1 and SAP-1 appear to interact with the c-fos SRE efficiently in vivo. Each TCF contains a C-terminal activation domain capable of transcriptional activation in response to activation of the Ras-Raf-ERK pathway, and this is dependent on the integrity of S/T-P motifs conserved between all the TCF family members. In contrast, activation of the SRE by whole serum and the mitogenic phospholipid LPA requires SRF binding alone. Constitutively activated members of the Rho subfamily of Ras-like GTPases are also capable of inducing activation of the SRE in the absence of TCF; unlike activated Ras itself, these proteins do not activate the TCFs in NIH3T3 cells. At the SRE, SRF- and TCF-linked signalling pathways act synergistically to potentiate transcription.

  18. Network analysis of epidermal growth factor signaling using integrated genomic, proteomic and phosphorylation data.

    Katrina M Waters

    Full Text Available To understand how integration of multiple data types can help decipher cellular responses at the systems level, we analyzed the mitogenic response of human mammary epithelial cells to epidermal growth factor (EGF using whole genome microarrays, mass spectrometry-based proteomics and large-scale western blots with over 1000 antibodies. A time course analysis revealed significant differences in the expression of 3172 genes and 596 proteins, including protein phosphorylation changes measured by western blot. Integration of these disparate data types showed that each contributed qualitatively different components to the observed cell response to EGF and that varying degrees of concordance in gene expression and protein abundance measurements could be linked to specific biological processes. Networks inferred from individual data types were relatively limited, whereas networks derived from the integrated data recapitulated the known major cellular responses to EGF and exhibited more highly connected signaling nodes than networks derived from any individual dataset. While cell cycle regulatory pathways were altered as anticipated, we found the most robust response to mitogenic concentrations of EGF was induction of matrix metalloprotease cascades, highlighting the importance of the EGFR system as a regulator of the extracellular environment. These results demonstrate the value of integrating multiple levels of biological information to more accurately reconstruct networks of cellular response.

  19. Network Analysis of Epidermal Growth Factor Signaling using Integrated Genomic, Proteomic and Phosphorylation Data

    Waters, Katrina M.; Liu, Tao; Quesenberry, Ryan D.; Willse, Alan R.; Bandyopadhyay, Somnath; Kathmann, Loel E.; Weber, Thomas J.; Smith, Richard D.; Wiley, H. S.; Thrall, Brian D.

    2012-03-29

    To understand how integration of multiple data types can help decipher cellular responses at the systems level, we analyzed the mitogenic response of human mammary epithelial cells to epidermal growth factor (EGF) using whole genome microarrays, mass spectrometry-based proteomics and large-scale western blots with over 1000 antibodies. A time course analysis revealed significant differences in the expression of 3172 genes and 596 proteins, including protein phosphorylation changes measured by western blot. Integration of these disparate data types showed that each contributed qualitatively different components to the observed cell response to EGF and that varying degrees of concordance in gene expression and protein abundance measurements could be linked to specific biological processes. Networks inferred from individual data types were relatively limited, whereas networks derived from the integrated data recapitulated the known major cellular responses to EGF and exhibited more highly connected signaling nodes than networks derived from any individual dataset. While cell cycle regulatory pathways were altered as anticipated, we found the most robust response to mitogenic concentrations of EGF was induction of matrix metalloprotease cascades, highlighting the importance of the EGFR system as a regulator of the extracellular environment. These results demonstrate the value of integrating multiple levels of biological information to more accurately reconstruct networks of cellular response.

  20. Cloning and expression analysis of myostatin, fibroblast growth factor 6, insulin-like growth factor I and II in liver and muscle of sea bass (Dicentrarchus labrax, L. during long-term fasting and refeeding

    M. Saroglia

    2010-04-01

    Full Text Available The exceptionally fast growth that fish experience after periods of fasting has been called “compensatory growth”. This phenomenon has been studied in intensive aquaculture as a means of enhancing growth rates, but the mechanisms by which food intake activates an increase in somatic growth, and especially in muscle growth, are complex and not yet fully understood. In the present paper, we describe the molecular cloning and sequencing of sea bass (Dicentrarchus labrax myostatin (MSTN and fibroblast growth factor 6 (FGF6, which have been shown to be major genetic determinants of skeletal muscle growth, together with insulin-like growth factor I (IGFI and IGF-II, which are potent mitogens known to play important roles in growth and development. We then report the pattern of expression of the four aforementioned genes, in liver and myotomal muscle in response to prolonged fasting and refeeding. Nutritional status significantly influenced the expression of IGF-I, IGF-II and MSTN, whereas the muscular FGF6 expression levels were not affected by the feeding status of the animals. Taken together these data indicate that IGF-I, IGF-II and MSTN are involved in the sea bass muscle compensatory growth induced by refeeding, whereas FGF6 probably has not a role in this phenomenon.

  1. SUSTAINABLE GROWTH: RECENT TRENDS ACROSS CENTRAL AND EASTERN EUROPEAN ECONOMIES

    Mihut Ioana

    2014-07-01

    Full Text Available What is economic growth? Although the answer to this question may seems of real simplicity, developing an accurate definition of this concept may constitute a real challenge both from a theoretical but also empirical point of view. This constant debate upon the concept of economic growth as well as indentifying the optimum set of instruments for quantifying it, constituted the starting point of the current article. The concept of economic growth is used nowadays complementary to terms like economic development, economic welfare or economic progress with reference to this complex process that implies macro-scale structures. Moreover indentifying the main factors that generate a significant impact upon the dynamics of the economic growth process, constitute a useful approach taking into consideration the high degree of heterogeneity that characterize the architecture of the economies around the world. If we develop this analysis across the European Union member states this debate became even more challenging due to the high degree of diversity that characterize these economies. Moreover, the Central and Eastern European countries and especially the ones that joined EU in 2004 and 2007 embody a set of particularities that make them extremely different from the rest of the European Union member states, features related to the historical background, economic policies and common efforts to intensify the convergence process with the more developed EU members. This paper studies the impact of two main factors upon the economic growth process namely an endogenous-exogenous factor like the degree of openness and an endogenous factor like the human capital using a complex dynamic panel method. The arguments that were in favour of choosing this two factors are on one hand the multitude of theoretical studies that argued the importance of them in modelling the economic growth process and on the other hand the small number of studies that use panel methods in

  2. Leucine zipper transcription factor-like 1 expression in gastric ...

    the gastric cancer tissues, and its relationship to cellular adhesion protein. ... related to cellular adhesion protein, but not to mRNA level. ... malignant tumors, and is correlated with gastric, ... The present study was aimed at investigating the.

  3. Epidermal growth factor induction of front–rear polarity and migration in keratinocytes is mediated by integrin-linked kinase and ELMO2

    Ho, Ernest; Dagnino, Lina

    2012-01-01

    Epidermal growth factor (EGF) is a potent chemotactic and mitogenic factor for epidermal keratinocytes, and these properties are central for normal epidermal regeneration after injury. The involvement of mitogen-activated protein kinases as mediators of the proliferative effects of EGF is well established. However, the molecular mechanisms that mediate motogenic responses to this growth factor are not clearly understood. An obligatory step for forward cell migration is the development of front–rear polarity and formation of lamellipodia at the leading edge. We show that stimulation of epidermal keratinocytes with EGF, but not with other growth factors, induces development of front–rear polarity and directional migration through a pathway that requires integrin-linked kinase (ILK), Engulfment and Cell Motility-2 (ELMO2), integrin β1, and Rac1. Furthermore, EGF induction of front–rear polarity and chemotaxis require the tyrosine kinase activity of the EGF receptor and are mediated by complexes containing active RhoG, ELMO2, and ILK. Our findings reveal a novel link between EGF receptor stimulation, ILK-containing complexes, and activation of small Rho GTPases necessary for acquisition of front–rear polarity and forward movement. PMID:22160594

  4. Epidermal growth factor induction of front-rear polarity and migration in keratinocytes is mediated by integrin-linked kinase and ELMO2.

    Ho, Ernest; Dagnino, Lina

    2012-02-01

    Epidermal growth factor (EGF) is a potent chemotactic and mitogenic factor for epidermal keratinocytes, and these properties are central for normal epidermal regeneration after injury. The involvement of mitogen-activated protein kinases as mediators of the proliferative effects of EGF is well established. However, the molecular mechanisms that mediate motogenic responses to this growth factor are not clearly understood. An obligatory step for forward cell migration is the development of front-rear polarity and formation of lamellipodia at the leading edge. We show that stimulation of epidermal keratinocytes with EGF, but not with other growth factors, induces development of front-rear polarity and directional migration through a pathway that requires integrin-linked kinase (ILK), Engulfment and Cell Motility-2 (ELMO2), integrin β1, and Rac1. Furthermore, EGF induction of front-rear polarity and chemotaxis require the tyrosine kinase activity of the EGF receptor and are mediated by complexes containing active RhoG, ELMO2, and ILK. Our findings reveal a novel link between EGF receptor stimulation, ILK-containing complexes, and activation of small Rho GTPases necessary for acquisition of front-rear polarity and forward movement.

  5. Skin rejuvenation using cosmetic products containing growth factors, cytokines, and matrikines: a review of the literature

    Aldag C

    2016-11-01

    Full Text Available Caroline Aldag,1,* Diana Nogueira Teixeira,1,* Phillip S Leventhal2 1Merz Pharmaceuticals GmbH, Frankfurt am Main, Germany; 24Clinics, Paris, France *These authors contributed equally to this work Abstract: Skin aging is primarily due to alterations in the dermal extracellular matrix, especially a decrease in collagen I content, fragmentation of collagen fibrils, and accumulation of amorphous elastin material, also known as elastosis. Growth factors and cytokines are included in several cosmetic products intended for skin rejuvenation because of their ability to promote collagen synthesis. Matrikines and matrikine-like peptides offer the advantage of growth factor-like activities but better skin penetration due to their much smaller molecular size. In this review, we summarize the commercially available products containing growth factors, cytokines, and matrikines for which there is evidence that they promote skin rejuvenation. Keywords: cosmetics, skin, aging, growth factor, cytokine, matrikine

  6. LmxMPK4, an essential mitogen-activated protein kinase of Leishmania mexicana is phosphorylated and activated by the STE7-like protein kinase LmxMKK5

    John von Freyend, Simona; Rosenqvist, Heidi; Fink, Annette

    2010-01-01

    The essential mitogen-activated protein kinase (MAP kinase), LmxMPK4, of Leishmania mexicana is minimally active when purified following recombinant expression in Escherichia coli and was therefore unsuitable for drug screening until now. Using an E. coli protein co-expression system we identified...... LmxMKK5, a STE7-like protein kinase from L. mexicana, which phosphorylates and activates recombinant LmxMPK4 in vitro. LmxMKK5 is comprised of 525 amino acids and has a calculated molecular mass of 55.9kDa. The co-expressed, purified LmxMPK4 showed strong phosphotransferase activity in radiometric...... kinase assays and was confirmed by immunoblot and tandem mass spectrometry analyses to be phosphorylated on threonine 190 and tyrosine 192 of the typical TXY MAP kinase activation motif. The universal protein kinase inhibitor staurosporine reduced the phosphotransferase activity of co...

  7. Simulating Population Growth.

    Byington, Scott

    1997-01-01

    Presents a strategy to help students grasp the important implications of population growth. Involves an interactive demonstration that allows students to experience exponential and logistic population growth followed by a discussion of the implications of population-growth principles. (JRH)

  8. Induction of viral, 7-methyl-guanosine cap-independent translation and oncolysis by mitogen-activated protein kinase-interacting kinase-mediated effects on the serine/arginine-rich protein kinase.

    Brown, Michael C; Bryant, Jeffrey D; Dobrikova, Elena Y; Shveygert, Mayya; Bradrick, Shelton S; Chandramohan, Vidyalakshmi; Bigner, Darell D; Gromeier, Matthias

    2014-11-01

    Protein synthesis, the most energy-consuming process in cells, responds to changing physiologic priorities, e.g., upon mitogen- or stress-induced adaptations signaled through the mitogen-activated protein kinases (MAPKs). The prevailing status of protein synthesis machinery is a viral pathogenesis factor, particularly for plus-strand RNA viruses, where immediate translation of incoming viral RNAs shapes host-virus interactions. In this study, we unraveled signaling pathways centered on the ERK1/2 and p38α MAPK-interacting kinases MNK1/2 and their role in controlling 7-methyl-guanosine (m(7)G) "cap"-independent translation at enterovirus type 1 internal ribosomal entry sites (IRESs). Activation of Raf-MEK-ERK1/2 signals induced viral IRES-mediated translation in a manner dependent on MNK1/2. This effect was not due to MNK's known functions as eukaryotic initiation factor (eIF) 4G binding partner or eIF4E(S209) kinase. Rather, MNK catalytic activity enabled viral IRES-mediated translation/host cell cytotoxicity through negative regulation of the Ser/Arg (SR)-rich protein kinase (SRPK). Our investigations suggest that SRPK activity is a major determinant of type 1 IRES competency, host cell cytotoxicity, and viral proliferation in infected cells. We are targeting unfettered enterovirus IRES activity in cancer with PVSRIPO, the type 1 live-attenuated poliovirus (PV) (Sabin) vaccine containing a human rhinovirus type 2 (HRV2) IRES. A phase I clinical trial of PVSRIPO with intratumoral inoculation in patients with recurrent glioblastoma (GBM) is showing early promise. Viral translation proficiency in infected GBM cells is a core requirement for the antineoplastic efficacy of PVSRIPO. Therefore, it is critically important to understand the mechanisms controlling viral cap-independent translation in infected host cells. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

  9. Effect of placental factors on growth and function of the human fetal adrenal in vitro.

    Riopel, L; Branchaud, C L; Goodyer, C G; Zweig, M; Lipowski, L; Adkar, V; Lefebvre, Y

    1989-11-01

    Conditioned medium from human placental monolayer cultures (PM) had a marked stimulatory effect on proliferation (3H-thymidine uptake) of human fetal zone adrenal cells in primary monolayer culture, even in the absence of serum. Epidermal growth factor (EGF) and fibroblast growth factor (FGF) also significantly stimulated fetal adrenal cell growth. However, the effects of PM differed from those of EGF and FGF in several respects: 1) maximal response to PM was 2-5 times greater; 2) mitogenic effects of EGF and FGF were suppressed by adrenocorticotropic hormone (ACTH), whereas that of 50% PM was not; 3) PM inhibited ACTH-stimulated steroidogenesis (dehydroepiandrosterone sulfate and cortisol), but EGF and FGF did not. Preliminary characterization studies have indicated that approximately half of the placental growth-promoting activity is heat resistant and sensitive to bacterial proteases, and that 50-60% of the activity is lost after dialysis with membranes having a molecular weight cutoff of 3500. These findings suggest a role for the placenta in the growth and differentiated function of the human fetal adrenal gland.

  10. Effect of placental factors on growth and function of the human fetal adrenal in vitro

    Riopel, L.; Branchaud, C.L.; Goodyer, C.G.; Zweig, M.; Lipowski, L.; Adkar, V.; Lefebvre, Y. (McGill Univ.-Montreal Children' s Hospital Research Institute, Quebec (Canada))

    1989-11-01

    Conditioned medium from human placental monolayer cultures (PM) had a marked stimulatory effect on proliferation (3H-thymidine uptake) of human fetal zone adrenal cells in primary monolayer culture, even in the absence of serum. Epidermal growth factor (EGF) and fibroblast growth factor (FGF) also significantly stimulated fetal adrenal cell growth. However, the effects of PM differed from those of EGF and FGF in several respects: (1) maximal response to PM was 2-5 times greater; (2) mitogenic effects of EGF and FGF were suppressed by adrenocorticotropic hormone (ACTH), whereas that of 50% PM was not; (3) PM inhibited ACTH-stimulated steroidogenesis (dehydroepiandrosterone sulfate and cortisol), but EGF and FGF did not. Preliminary characterization studies have indicated that approximately half of the placental growth-promoting activity is heat resistant and sensitive to bacterial proteases, and that 50-60% of the activity is lost after dialysis with membranes having a molecular weight cutoff of 3500. These findings suggest a role for the placenta in the growth and differentiated function of the human fetal adrenal gland.

  11. Effect of placental factors on growth and function of the human fetal adrenal in vitro

    Riopel, L.; Branchaud, C.L.; Goodyer, C.G.; Zweig, M.; Lipowski, L.; Adkar, V.; Lefebvre, Y.

    1989-01-01

    Conditioned medium from human placental monolayer cultures (PM) had a marked stimulatory effect on proliferation (3H-thymidine uptake) of human fetal zone adrenal cells in primary monolayer culture, even in the absence of serum. Epidermal growth factor (EGF) and fibroblast growth factor (FGF) also significantly stimulated fetal adrenal cell growth. However, the effects of PM differed from those of EGF and FGF in several respects: (1) maximal response to PM was 2-5 times greater; (2) mitogenic effects of EGF and FGF were suppressed by adrenocorticotropic hormone (ACTH), whereas that of 50% PM was not; (3) PM inhibited ACTH-stimulated steroidogenesis (dehydroepiandrosterone sulfate and cortisol), but EGF and FGF did not. Preliminary characterization studies have indicated that approximately half of the placental growth-promoting activity is heat resistant and sensitive to bacterial proteases, and that 50-60% of the activity is lost after dialysis with membranes having a molecular weight cutoff of 3500. These findings suggest a role for the placenta in the growth and differentiated function of the human fetal adrenal gland

  12. AMSAA Reliability Growth Guide

    Broemm, William

    2000-01-01

    ... has developed reliability growth methodology for all phases of the process, from planning to tracking to projection. The report presents this methodology and associated reliability growth concepts.

  13. EphA2 is a functional receptor for the growth factor progranulin.

    Neill, Thomas; Buraschi, Simone; Goyal, Atul; Sharpe, Catherine; Natkanski, Elizabeth; Schaefer, Liliana; Morrione, Andrea; Iozzo, Renato V

    2016-12-05

    Although the growth factor progranulin was discovered more than two decades ago, the functional receptor remains elusive. Here, we discovered that EphA2, a member of the large family of Ephrin receptor tyrosine kinases, is a functional signaling receptor for progranulin. Recombinant progranulin bound with high affinity to EphA2 in both solid phase and solution. Interaction of progranulin with EphA2 caused prolonged activation of the receptor, downstream stimulation of mitogen-activated protein kinase and Akt, and promotion of capillary morphogenesis. Furthermore, we found an autoregulatory mechanism of progranulin whereby a feed-forward loop occurred in an EphA2-dependent manner that was independent of the endocytic receptor sortilin. The discovery of a functional signaling receptor for progranulin offers a new avenue for understanding the underlying mode of action of progranulin in cancer progression, tumor angiogenesis, and perhaps neurodegenerative diseases. © 2016 Neill et al.

  14. PLZF regulates fibroblast growth factor responsiveness and maintenance of neural progenitors.

    Gaber, Zachary B; Butler, Samantha J; Novitch, Bennett G

    2013-10-01

    Distinct classes of neurons and glial cells in the developing spinal cord arise at specific times and in specific quantities from spatially discrete neural progenitor domains. Thus, adjacent domains can exhibit marked differences in their proliferative potential and timing of differentiation. However, remarkably little is known about the mechanisms that account for this regional control. Here, we show that the transcription factor Promyelocytic Leukemia Zinc Finger (PLZF) plays a critical role shaping patterns of neuronal differentiation by gating the expression of Fibroblast Growth Factor (FGF) Receptor 3 and responsiveness of progenitors to FGFs. PLZF elevation increases FGFR3 expression and STAT3 pathway activity, suppresses neurogenesis, and biases progenitors towards glial cell production. In contrast, PLZF loss reduces FGFR3 levels, leading to premature neuronal differentiation. Together, these findings reveal a novel transcriptional strategy for spatially tuning the responsiveness of distinct neural progenitor groups to broadly distributed mitogenic signals in the embryonic environment.

  15. Post-transcriptional regulation of vascular endothelial growth factor: Implications for tumor angiogenesis

    Peter S Yoo; Abby L Mulkeen; Charles H Cha

    2006-01-01

    Vascular endothelial growth factor (VEGF) is a potent secreted mitogen critical for physiologic and tumor angiogenesis. Regulation of VEGF occurs at several levels, including transcription, mRNA stabilization,translation, and differential cellular localization of various isoforms. Recent advances in our understanding of posttranscriptional regulation of VEGF include identification of the stabilizing mRNA binding protein, HuR, and the discovery of internal ribosomal entry sites in the 5'UTR of the VEGF mRNA. Monoclonal anti-VEGF antibody was recently approved for use in humans, but suffers from the need for high systemic doses. RNA interference (RNAi)technology is being used in vitro and in animal models with promising results. Here, we review the literature on post-transcriptional regulation of VEGF and describe recent progress in targeting these mechanisms for therapeutic benefit.

  16. Growth of human T lymphocyte colonies from whole blood: culture requirements and applications

    Knox, S.J.; Wilson, F.D.; Greenberg, B.R.; Shifrine, M.

    1982-01-01

    Growth of human lymphocyte colonies from whole blood following stimulation with PHA, Con A, or PPD is described. Individual colony cells were identified as T lymphocytes on the basis of surface marker and enzyme cytochemical characterizations. Colony formation increased as a power function over a wide range of cell concentrations above a critical minimal concentration. The whole blood culture system eliminates possible selective effects of lymphocyte colony techniques utilizing gradient-enriched lymphocyte fractions and more closely approximates the in vivo milieu. The whole blood colony method is more sensitive for the detection of low-level radiation effects on lymphocytes than widely used tests that measure 3 H-thymidine incorporation. In preliminary studies, researchers used the whole blood method to determine the relative radiosensitivity of lymphocytes from humans with various hematopoietic disorders, and observed abnormalities in mitogen responsiveness and colony formation in some of the patient groups. This method has wide application for studies in cellular and clinical immunology

  17. Does epidermal growth factor play a role in the action of sucralfate?

    Nexø, Ebba; Poulsen, Steen Seier

    1987-01-01

    Epidermal growth factor (EGF) is a mitogenic peptide synthesized in the submandibular glands and released in saliva. EGF is able to prevent the development of gastrointestinal ulcers in the rat and to accelerate their healing. The present work was undertaken to examine whether Sucralfate acts via...... the effector system of EGF. We conclude that Sucralfate does not change the binding of EGF to its receptor, but it is able to bind EGF in a pH dependent manner and at pH below 4.5 virtually all EGF is bound to Sucralfate. In vivo studies in rats with acid-induced gastric ulcers show that sucralfate carries EGF...... to the ulcer, and that EGF is available for a longer period of time (3 hours) when EGF and Sucralfate are is given together than when EGF is given alone....

  18. Insulin like growth factor-1/insulin bypasses Pref-1/FA1-mediated inhibition of adipocyte differentiation

    Zhang, Hongbin; Nøhr, Jane; Jensen, Charlotte Harken

    2003-01-01

    that forced expression of the soluble form, FA1, or full-length Pref-1 did not inhibit adipocyte differentiation of 3T3-L1 cells when differentiation was induced by standard treatment with methylisobutylxanthine, dexamethasone, and high concentrations of insulin. However, forced expression of either form...... of Pref-1/FA1 in 3T3-L1 or 3T3-F442A cells inhibited adipocyte differentiation when insulin or insulin-like growth factor-1 (IGF-1) was omitted from the differentiation mixture. We demonstrate that the level of the mature form of the IGF-1 receptor is reduced and that IGF-1-dependent activation of p42/p44...... mitogen-activated protein kinases (MAPKs) is compromised in preadipocytes with forced expression of Pref-1. This is accompanied by suppression of clonal expansion and terminal differentiation. Accordingly, supplementation with insulin or IGF-1 rescued p42/p44 MAPK activation, clonal expansion...

  19. Angiopoietin-related growth factor (AGF) supports adhesion, spreading, and migration of keratinocytes, fibroblasts, and endothelial cells through interaction with RGD-binding integrins

    Zhang Yueqing; Hu Xiaobo; Tian Ruiyang; Wei Wangui; Hu Wei; Chen Xia; Han Wei; Chen Huayou; Gong Yi

    2006-01-01

    Angiopoietin-related growth factor (AGF) is a newly identified member of angiopoietin-related proteins (ARPs)/angiopoietin-like proteins (Angptls). AGF has been considered as a novel growth factor in accelerating cutaneous wound healing, as it is capable of stimulating keratinocytes proliferation as well as angiogenesis. But in our paper, we demonstrate that AGF stimulates keratinocytes proliferation only at high protein concentration, however, it can potently promote adhesion, spreading, and migration of keratinocytes, fibroblasts, and endothelial cells. Furthermore, we confirm that the adhesion and migration cellular events are mediated by RGD-binding integrins, most possibly the α v -containing integrins, by in vitro inhibition assays using synthetic competitive peptides. Our results strongly suggest that AGF is an integrin ligand as well as a mitogenic growth factor and theoretically participates in cutaneous wound healing in a more complex mechanism

  20. PaASK1, a mitogen-activated protein kinase kinase kinase that controls cell degeneration and cell differentiation in Podospora anserina.

    Kicka, Sébastien; Silar, Philippe

    2004-03-01

    MAPKKK are kinases involved in cell signaling. In fungi, these kinases are known to regulate development, pathogenicity, and the sensing of external conditions. We show here that Podospora anserina strains mutated in PaASK1, a MAPKKK of the MEK family, are impaired in the development of crippled growth, a cell degeneration process caused by C, a nonconventional infectious element. They also display defects in mycelium pigmentation, differentiation of aerial hyphae, and making of fruiting bodies, three hallmarks of cell differentiation during stationary phase in P. anserina. Overexpression of PaASK1 results in exacerbation of crippled growth. PaASK1 is a large protein of 1832 amino acids with several domains, including a region rich in proline and a 60-amino-acid-long polyglutamine stretch. Deletion analysis reveals that the polyglutamine stretch is dispensable for PaASK1 activity, whereas the region that contains the prolines is essential but insufficient to promote full activity. We discuss a model based on the hysteresis of a signal transduction cascade to account for the role of PaASK1 in both cell degeneration and stationary-phase cell differentiation.

  1. Morphine induces expression of platelet-derived growth factor in human brain microvascular endothelial cells: implication for vascular permeability.

    Hongxiu Wen

    Full Text Available Despite the advent of antiretroviral therapy, complications of HIV-1 infection with concurrent drug abuse are an emerging problem. Morphine, often abused by HIV-infected patients, is known to accelerate neuroinflammation associated with HIV-1 infection. Detailed molecular mechanisms of morphine action however, remain poorly understood. Platelet-derived growth factor (PDGF has been implicated in a number of pathological conditions, primarily due to its potent mitogenic and permeability effects. Whether morphine exposure results in enhanced vascular permeability in brain endothelial cells, likely via induction of PDGF, remains to be established. In the present study, we demonstrated morphine-mediated induction of PDGF-BB in human brain microvascular endothelial cells, an effect that was abrogated by the opioid receptor antagonist-naltrexone. Pharmacological blockade (cell signaling and loss-of-function (Egr-1 approaches demonstrated the role of mitogen-activated protein kinases (MAPKs, PI3K/Akt and the downstream transcription factor Egr-1 respectively, in morphine-mediated induction of PDGF-BB. Functional significance of increased PDGF-BB manifested as increased breach of the endothelial barrier as evidenced by decreased expression of the tight junction protein ZO-1 in an in vitro model system. Understanding the regulation of PDGF expression may provide insights into the development of potential therapeutic targets for intervention of morphine-mediated neuroinflammation.

  2. Green growth in fisheries

    Nielsen, Max; Ravensbeck, Lars; Nielsen, Rasmus

    2014-01-01

    harming the environment. Fishery is an environment-dependent sector and it has been argued that there is no potential for green growth in the sector owing to global overexploitation, leaving no scope for production growth. The purpose of this paper is to explain what green growth is and to develop......Climate change and economic growth have gained a substantial amount of attention over the last decade. Hence, in order to unite the two fields of interest, the concept of green growth has evolved. The concept of green growth focuses on how to achieve growth in environment-dependent sectors, without...... a conceptual framework. Furthermore, the aim is to show that a large green growth potential actually exists in fisheries and to show how this potential can be achieved. The potential green growth appears as value-added instead of production growth. The potential can be achieved by reducing overcapacity...

  3. Posttraumatic growth in cancer patients and partners--effects of role, gender and the dyad on couples' posttraumatic growth experience.

    Zwahlen, Diana; Hagenbuch, Niels; Carley, Margaret I; Jenewein, Josef; Buchi, Stefan

    2010-01-01

    Little is known about factors influencing positive effects in couples facing a cancer diagnosis. A heterogeneous sample of 224 couples from a multi-site study (four oncology units) completed questionnaire surveys including the Posttraumatic Growth Inventory (PTGI) as a measure of positive psychological effects. The data demonstrated that all three investigated factors--gender, role (patient vs partner) and the dyad (belonging to any of the 224 couples)--significantly contributed to variation in PTGI total scores and subscales. Variability between couples (factor dyad) appeared stronger than variability between patient and partner participants (factor role) and between male and female participants (factor gender). Role and gender analysis showed that patients demonstrated higher levels of posttraumatic growth than partners; and female participants scored higher on PTGI than males. Male patient-female partner pairs show greater association in their experience of posttraumatic growth than female patient-male partner pairs. Correlations also suggested that, regardless of the gender and role composition, patients and partners may experience parallel growth. Our findings indicate that positive psychological experiences may be shared by partners affected by cancer in similar ways as have been shown for negative psychological effects. Intra-couple similarities or processes may have a more important function in experiencing benefits than factors like gender or being the patient or the partner. These results underline the importance of a family approach to understanding negative and positive psychological effects of cancer. (c) 2009 John Wiley & Sons, Ltd.

  4. Insulin-like growth factor (IGF)-like peptide and 20-hydroxyecdysone regulate the growth and development of the male genital disk through different mechanisms in the silkmoth, Bombyx mori.

    Fujinaga, Daiki; Kohmura, Yusuke; Okamoto, Naoki; Kataoka, Hiroshi; Mizoguchi, Akira

    2017-08-01

    It is well established that ecdysteroids play pivotal roles in the regulation of insect molting and metamorphosis. However, the mechanisms by which ecdysteroids regulate the growth and development of adult organs after pupation are poorly understood. Recently, we have identified insulin-like growth factor (IGF)-like peptides (IGFLPs), which are secreted after pupation under the control of 20-hydroxyecdysone (20E). In the silkmoth, Bombyx mori, massive amounts of Bombyx-IGFLP (BIGFLP) are present in the hemolymph during pupal-adult development, suggesting its importance in the regulation of adult tissue growth. Thus, we hypothesized that the growth and development of adult tissues including imaginal disks are regulated by the combined effects of BIGFLP and 20E. In this study, we investigated the growth-promoting effects of BIGFLP and 20E using the male genital disks of B. mori cultured ex vivo, and further analyzed the cell signaling pathways mediating hormone actions. We demonstrate that 20E induces the elongation of genital disks, that both hormones stimulate protein synthesis in an additive manner, and that BIGFLP and 20E exert their effects through the insulin/IGF signaling pathway and mitogen-activated protein kinase pathway, respectively. These results show that the growth and development of the genital disk are coordinately regulated by both BIGFLP and 20E. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Role of nongenomic activation of phosphatidylinositol 3-kinase/Akt and mitogen-activated protein kinase/extracellular signal-regulated kinase kinase/extracellular signal-regulated kinase 1/2 pathways in 1,25D3-mediated apoptosis in squamous cell carcinoma cells.

    Ma, Yingyu; Yu, Wei-Dong; Kong, Rui-Xian; Trump, Donald L; Johnson, Candace S

    2006-08-15

    Vitamin D is a steroid hormone that regulates calcium homeostasis and bone metabolism. The active form of vitamin D [1 alpha,25-dihydroxyvitamin D(3) (1,25D3)] acts through both genomic and nongenomic pathways. 1,25D3 has antitumor effects in a variety of cancers, including colorectal, prostate, breast, ovarian, and skin cancers. 1,25D3 exerts growth-inhibitory effects in cancer cells through the induction of apoptosis, cell cycle arrest, and differentiation. The mechanisms regulating 1,25D3-induced apoptosis remain unclear. We investigated the role of nongenomic signaling in 1,25D3-mediated apoptosis in squamous cell carcinoma (SCC) cells. 1,25D3 induced rapid and sustained activation of phosphatidylinositol 3-kinase/Akt and mitogen-activated protein kinase/extracellular signal-regulated kinase (ERK) 1/2 pathways in SCC cells. These effects were nongenomic: they occurred rapidly and were not inhibited by cycloheximide or actinomycin D. To examine whether the nongenomic activation of Akt and ERK1/2 plays a role in 1,25D3-mediated apoptosis, the expression of Akt or ERK1/2 was reduced by small interfering RNA (siRNA). siRNA-Akt significantly enhanced 1,25D3-induced apoptosis as indicated by increased levels of Annexin V-positive cells and increased sub-G(1) population and DNA fragmentation. In contrast, siRNA-ERK1/2 had no effects on 1,25D3-induced apoptosis. In addition, siRNA-Akt transfection followed by 1,25D3 treatment induced apoptosis much sooner than 1,25D3 alone. siRNA-Akt and 1,25D3 induced caspase-10 activation, suppressed the expression of c-IAP1 and XIAP, and promoted 1,25D3-induced caspase-3 activation. These results support a link between 1,25D3-induced nongenomic signaling and apoptosis. 1,25D3 induces the activation of phosphatidylinositol 3-kinase/Akt, which suppresses 1,25D3-mediated apoptosis and prolongs the survival of SCC cells.

  6. Noonan syndrome: an update on growth and development.

    Yart, Armelle; Edouard, Thomas

    2018-02-01

    To provide an update on recent developments on Noonan syndrome with a special focus on endocrinology, bone, and metabolism aspects. The key issues still to be resolved and the future therapeutic perspectives will be discussed. The discovery of the molecular genetic causes of Noonan syndrome and Noonan-syndrome-related disorders has permitted us to better understand the mechanisms underlying the different symptoms of these diseases and to establish genotype-phenotype correlations (in growth patterns for example). In addition to the classical clinical hallmarks of Noonan syndrome, new important aspects include decreased fertility in men, lean phenotype with increased energy expenditure and possible impact on carbohydrate metabolism/insulin sensitivity, and impaired bone health. Further clinical studies are needed to investigate the long-term impact of these findings and their possible interconnections. Finally, the understanding of the crucial role of RAS/mitogen-activated protein kinases dysregulation in the pathophysiology of Noonan syndrome allows us to devise new therapeutic approaches. Some agents are currently undergoing clinical trials in Noonan syndrome patients. On the last 10 years, our knowledge of the molecular basis and the pathophysiology of Noonan syndrome has greatly advanced allowing us to gain insight in all the aspects of this disease and to devise new specific therapeutic strategies.

  7. Signal transduction by the platelet-derived growth factor receptor

    Williams, L.T.; Escobedo, J.A.; Keating, M.T.; Coughlin, S.R.

    1988-01-01

    The mitogenic effects of platelet-derived growth factor (PDGF) are mediated by the PDGF receptor. The mouse PDGF receptor was recently purified on the basis of its ability to become tyrosine phosphorylated in response to the A-B human platelet form of PDGF, and the receptor amino acid sequence was determined from a full-length cDNA clone. Both the human and mouse receptor cDNA sequences have been expressed in Chinese hamster ovary fibroblast (CHO) cells that normally lack PDGF receptors. This paper summarizes recent results using this system to study signal transduction by the PDGF receptor. Some of the findings show that the KI domain of the PDGF receptor plays an important role in the stimulation of DNA synthesis by PDGF. Surprisingly, the kinase insert region is not essential for PDGF stimulation of PtdIns turnover, pH change, increase in cellular calcium, and receptor autophosphorylation. In addition, PDGF stimulates a conformational change in the receptor

  8. Mitogen-activated protein kinase kinase kinase (MAPKKK) 4 from rapeseed (Brassica napus L.) is a novel member inducing ROS accumulation and cell death

    Li, Liang, E-mail: 18710470987@163.com; Ye, Chaofei, E-mail: yechaofei001@163.com; Zhao, Rui, E-mail: 571828628@qq.com; Li, Xin, E-mail: 1458272138@qq.com; Liu, Wu-zhen, E-mail: happywuzhenliu@163.com; Wu, Feifei, E-mail: 283915941@qq.com; Yan, Jingli, E-mail: yanjingli512@163.com; Jiang, Yuan-Qing, E-mail: jiangyq@nwafu.edu.cn; Yang, Bo, E-mail: yangwl@nwafu.edu.cn

    2015-11-27

    MAPKKK is the largest family of MAPK cascade, which is known to play important roles in plant growth, development and immune responses. So far, only a few have been functionally characterized even in the model plant, Arabidopsis due to the potential functional redundancy of MAPKKK. We previously identified and cloned a few MAPKKK family genes from rapeseed. In this study, BnaMAPKKK4 was characterized as a member in eliciting accumulation of reactive oxygen species (ROS) and hypersensitive response (HR)-like cell death. This is accompanied with accumulation of malondialdehyde (MDA), anthocyanin as well as nuclear DNA fragmentation. The transcript abundance of a series of ROS accumulation, cell death, and defense response related genes were up-regulated by the expression of MAPKKK4. Further investigation identified BnaMAPKKK4 elicited ROS through the downstream MPK3. These results indicate that BnaMAPKKK4 and its downstream components function in the ROS-induced cell death. - Highlights: • Expression of rapeseed MAPKKK4 induced ROS accumulation and cell death in leaves. • Cell death induced by MAPKKK4 is associated with membrane lipid peroxidation and DNA fragmentation. • MAPKKK4 interacts with MKK5 and MPK3. • MAPKKK4-induced ROS accumulation and cell death require downstream WIPK and SIPK. • MAPKKK4 is a novel MAPKKK modulating ROS accumulation and cell death.

  9. Mitogen-activated protein kinase kinase kinase (MAPKKK) 4 from rapeseed (Brassica napus L.) is a novel member inducing ROS accumulation and cell death

    Li, Liang; Ye, Chaofei; Zhao, Rui; Li, Xin; Liu, Wu-zhen; Wu, Feifei; Yan, Jingli; Jiang, Yuan-Qing; Yang, Bo

    2015-01-01

    MAPKKK is the largest family of MAPK cascade, which is known to play important roles in plant growth, development and immune responses. So far, only a few have been functionally characterized even in the model plant, Arabidopsis due to the potential functional redundancy of MAPKKK. We previously identified and cloned a few MAPKKK family genes from rapeseed. In this study, BnaMAPKKK4 was characterized as a member in eliciting accumulation of reactive oxygen species (ROS) and hypersensitive response (HR)-like cell death. This is accompanied with accumulation of malondialdehyde (MDA), anthocyanin as well as nuclear DNA fragmentation. The transcript abundance of a series of ROS accumulation, cell death, and defense response related genes were up-regulated by the expression of MAPKKK4. Further investigation identified BnaMAPKKK4 elicited ROS through the downstream MPK3. These results indicate that BnaMAPKKK4 and its downstream components function in the ROS-induced cell death. - Highlights: • Expression of rapeseed MAPKKK4 induced ROS accumulation and cell death in leaves. • Cell death induced by MAPKKK4 is associated with membrane lipid peroxidation and DNA fragmentation. • MAPKKK4 interacts with MKK5 and MPK3. • MAPKKK4-induced ROS accumulation and cell death require downstream WIPK and SIPK. • MAPKKK4 is a novel MAPKKK modulating ROS accumulation and cell death.

  10. The investigation of Mitogen-Activated Protein kinase Phosphatase-1 as a potential pharmacological target in non-small cell lung carcinomas, assisted by non-invasive molecular imaging

    Tai, Cheng-Jeng; Lee, Horng-Mo; Deng, Win-Ping; Wu, Alexander TH; Chiou, Jeng-Feng; Jan, Hsun-Jin; Wei, Hon-Jian; Hsu, Chung-Huei; Lin, Che-Tong; Chiu, Wen-Ta; Wu, Cheng-Wen

    2010-01-01

    Invasiveness and metastasis are the most common characteristics of non small cell lung cancer (NSCLC) and causes of tumour-related morbidity and mortality. Mitogen-activated protein kinases (MAPKs) signalling pathways have been shown to play critical roles in tumorigenesis. However, the precise pathological role(s) of mitogen-activated protein kinase phosphatase-1 (MKP-1) in different cancers has been controversial such that the up-regulation of MKP-1 in different cancers does not always correlate to a better prognosis. In this study, we showed that the induction of MKP-1 lead to a significant retardation of proliferation and metastasis in NSCLC cells. We also established that rosiglitazone (a PPARγ agonist) elevated MKP-1 expression level in NSCLC cells and inhibited tumour metastasis. Both wildtype and dominant negative forms of MKP-1 were constitutively expressed in NSCLC cell line H441GL. The migration and invasion abilities of these cells were examined in vitro. MKP-1 modulating agents such as rosiglitazone and triptolide were used to demonstrate MKP-1's role in tumorigenesis. Bioluminescent imaging was utilized to study tumorigenesis of MKP-1 over-expressing H441GL cells and anti-metastatic effect of rosiglitazone. Over-expression of MKP-1 reduced NSCLC cell proliferation rate as well as cell invasive and migratory abilities, evident by the reduced expression levels of MMP-2 and CXCR4. Mice inoculated with MKP-1 over-expressing H441 cells did not develop NSCLC while their control wildtype H441 inoculated littermates developed NSCLC and bone metastasis. Pharmacologically, rosiglitazone, a peroxisome proliferator activated receptor-γ (PPARγ) agonist appeared to induce MKP-1 expression while reduce MMP-2 and CXCR4 expression. H441GL-inoculated mice receiving daily oral rosiglitazone treatment demonstrated a significant inhibition of bone metastasis when compared to mice receiving sham treatment. We found that rosiglitazone treatment impeded the ability

  11. Growth performance and gastrointestinal responses of broiler chickens fed corn-soybean meal diet without or with exogenous epidermal growth factor upon challenge with Eimeria1

    Kim, E.; Leung, H.; Akhtar, N.; Li, J.; Barta, J. R.; Wang, Y.; Yang, C.; Kiarie, E.

    2017-01-01

    Abstract Epidermal growth factor (EGF), a protein known for its mitogenic and anti-apoptotic effects was fed to broiler chickens to evaluate growth performance, gastrointestinal measurements, and apparent retention (AR) of components upon challenge with Eimeria. A total of 216, d old male broiler chicks (Ross 708) were placed in cages (6 birds/cage) and allocated to treatments. The treatments were: 1) control (Lactotobacilli lactis fermentation supernatant without EGF), 2) 80 μg of EGF/kg BW/d, and 3) 160 μg of EGF/kg BW/d. A basal antibiotic-free corn-soybean diet containing TiO2 was used. Birds were offered fresh feed with respective treatments on daily basis and had free access to drinking water for 14 d. On d 5, birds (6 replicates per treatment) were challenged with 1 mL of E. acervulina and E. maxima mixture via oral gavage and the other 6 replicates were given sham. Growth performance was measured in pre- (d 0 to 5) and post- (d 6 to 14) challenge periods. Two birds per cage were necropsied on d 10 for intestinal lesion scores and tissue samples for histomorphology and expression of select intestinal genes. Excreta samples for AR of components and oocyst shedding were taken d 10 to 13 and all birds were necropsied on d 14 for gastrointestinal weight. The EGF linearly (P Eimeria interaction (P > 0.05) on growth performance, AR of GE, and intestinal histomorphology; the main effects were such that Eimeria depressed (P Eimeria (P Eimeria challenged birds whilst no effect in non-challenged control. In conclusion, Eimeria challenge reduced growth performance and impaired gut function; EGF showed beneficial effects on growth pre-challenge and improved indices of gut function upon Eimeria challenge. PMID:28938785

  12. Growth performance and gastrointestinal responses of broiler chickens fed corn-soybean meal diet without or with exogenous epidermal growth factor upon challenge with Eimeria.

    Kim, E; Leung, H; Akhtar, N; Li, J; Barta, J R; Wang, Y; Yang, C; Kiarie, E

    2017-10-01

    Epidermal growth factor (EGF), a protein known for its mitogenic and anti-apoptotic effects was fed to broiler chickens to evaluate growth performance, gastrointestinal measurements, and apparent retention (AR) of components upon challenge with Eimeria. A total of 216, d old male broiler chicks (Ross 708) were placed in cages (6 birds/cage) and allocated to treatments. The treatments were: 1) control (Lactotobacilli lactis fermentation supernatant without EGF), 2) 80 μg of EGF/kg BW/d, and 3) 160 μg of EGF/kg BW/d. A basal antibiotic-free corn-soybean diet containing TiO2 was used. Birds were offered fresh feed with respective treatments on daily basis and had free access to drinking water for 14 d. On d 5, birds (6 replicates per treatment) were challenged with 1 mL of E. acervulina and E. maxima mixture via oral gavage and the other 6 replicates were given sham. Growth performance was measured in pre- (d 0 to 5) and post- (d 6 to 14) challenge periods. Two birds per cage were necropsied on d 10 for intestinal lesion scores and tissue samples for histomorphology and expression of select intestinal genes. Excreta samples for AR of components and oocyst shedding were taken d 10 to 13 and all birds were necropsied on d 14 for gastrointestinal weight. The EGF linearly (P Eimeria interaction (P > 0.05) on growth performance, AR of GE, and intestinal histomorphology; the main effects were such that Eimeria depressed (P Eimeria (P Eimeria challenged birds whilst no effect in non-challenged control. In conclusion, Eimeria challenge reduced growth performance and impaired gut function; EGF showed beneficial effects on growth pre-challenge and improved indices of gut function upon Eimeria challenge. © The Author 2017. Published by Oxford University Press on behalf of Poultry Science Association.

  13. Fast growth associated with aberrant vasculature and hypoxia in fibroblast growth factor 8b (FGF8b) over-expressing PC-3 prostate tumour xenografts

    Tuomela, Johanna; Solin, Olof; Minn, Heikki; Härkönen, Pirkko L; Grönroos, Tove J; Valta, Maija P; Sandholm, Jouko; Schrey, Aleksi; Seppänen, Jani; Marjamäki, Päivi; Forsback, Sarita; Kinnunen, Ilpo

    2010-01-01

    Prostate tumours are commonly poorly oxygenated which is associated with tumour progression and development of resistance to chemotherapeutic drugs and radiotherapy. Fibroblast growth factor 8b (FGF8b) is a mitogenic and angiogenic factor, which is expressed at an increased level in human prostate tumours and is associated with a poor prognosis. We studied the effect of FGF8b on tumour oxygenation and growth parameters in xenografts in comparison with vascular endothelial growth factor (VEGF)-expressing xenografts, representing another fast growing and angiogenic tumour model. Subcutaneous tumours of PC-3 cells transfected with FGF8b, VEGF or empty (mock) vectors were produced and studied for vascularity, cell proliferation, glucose metabolism and oxygenation. Tumours were evaluated by immunohistochemistry (IHC), flow cytometry, use of radiolabelled markers of energy metabolism ([ 18 F]FDG) and hypoxia ([ 18 F]EF5), and intratumoral polarographic measurements of pO 2 . Both FGF8b and VEGF tumours grew rapidly in nude mice and showed highly vascularised morphology. Perfusion studies, pO 2 measurements, [ 18 F]EF5 and [ 18 F]FDG uptake as well as IHC staining for glucose transport protein (GLUT1) and hypoxia inducible factor (HIF) 1 showed that VEGF xenografts were well-perfused and oxygenised, as expected, whereas FGF8b tumours were as hypoxic as mock tumours. These results suggest that FGF8b-induced tumour capillaries are defective. Nevertheless, the growth rate of hypoxic FGF8b tumours was highly increased, as that of well-oxygenised VEGF tumours, when compared with hypoxic mock tumour controls. FGF8b is able to induce fast growth in strongly hypoxic tumour microenvironment whereas VEGF-stimulated growth advantage is associated with improved perfusion and oxygenation of prostate tumour xenografts

  14. Globalization, Growth and Poverty

    One-pagers are a publication of IDRC's “Globalization, Growth and Poverty” Program Initiative, and are based on ... countries, mainly the fast-growing economies of East Asia. ... had no significant overall impact on investment and growth. Other.

  15. Measuring multifactor productivity growth

    Wölfl, A.; Hájková, Dana

    -, 2007/5 (2007), s. 1-45 Institutional research plan: CEZ:AV0Z70850503 Keywords : multifactor productivity growth * GDP growth * measuring Subject RIV: AH - Economics http://www.oecd.org/dataoecd/61/17/39522985.pdf

  16. Growth hormone test

    ... is called acromegaly . In children it is called gigantism . Too little growth hormone can cause a slow ... growth due to excess GH during childhood, called gigantism. (A special test is done to confirm this ...

  17. CDC Child Growth Charts

    U.S. Department of Health & Human Services — CDC child growth charts consist of a series of percentile curves that illustrate the distribution of selected body measurements in U.S. children. Pediatric growth...

  18. Growth hormone stimulation test

    ... this page: //medlineplus.gov/ency/article/003377.htm Growth hormone stimulation test To use the sharing features on this page, please enable JavaScript. The growth hormone (GH) stimulation test measures the ability of ...

  19. Normal growth and development

    ... page: //medlineplus.gov/ency/article/002456.htm Normal growth and development To use the sharing features on this page, please enable JavaScript. A child's growth and development can be divided into four periods: ...

  20. Inhibition of Dengue Virus Replication by a Class of Small-Molecule Compounds That Antagonize Dopamine Receptor D4 and Downstream Mitogen-Activated Protein Kinase Signaling

    Smith, Jessica L.; Stein, David A.; Shum, David; Fischer, Matthew A.; Radu, Constantin; Bhinder, Bhavneet; Djaballah, Hakim; Nelson, Jay A.; Früh, Klaus

    2014-01-01

    ABSTRACT Dengue viruses (DENV) are endemic pathogens of tropical and subtropical regions that cause significant morbidity and mortality worldwide. To date, no vaccines or antiviral therapeutics have been approved for combating DENV-associated disease. In this paper, we describe a class of tricyclic small-molecule compounds—dihydrodibenzothiepines (DHBTs), identified through high-throughput screening—with potent inhibitory activity against DENV serotype 2. SKI-417616, a highly active representative of this class, displayed activity against all four serotypes of DENV, as well as against a related flavivirus, West Nile virus (WNV), and an alphavirus, Sindbis virus (SINV). This compound was characterized to determine its mechanism of antiviral activity. Investigation of the stage of the viral life cycle affected revealed that an early event in the life cycle is inhibited. Due to the structural similarity of the DHBTs to known antagonists of the dopamine and serotonin receptors, we explored the roles of two of these receptors, serotonin receptor 2A (5HTR2A) and the D4 dopamine receptor (DRD4), in DENV infection. Antagonism of DRD4 and subsequent downstream phosphorylation of epidermal growth factor receptor (EGFR)-related kinase (ERK) were found to impact DENV infection negatively, and blockade of signaling through this network was confirmed as the mechanism of anti-DENV activity for this class of compounds. IMPORTANCE The dengue viruses are mosquito-borne, reemerging human pathogens that are the etiological agents of a spectrum of febrile diseases. Currently, there are no approved therapeutic treatments for dengue-associated disease, nor is there a vaccine. This study identifies a small molecule, SKI-417616, with potent anti-dengue virus activity. Further analysis revealed that SKI-417616 acts through antagonism of the host cell dopamine D4 receptor and subsequent repression of the ERK phosphorylation pathway. These results suggest that SKI-417616, or other

  1. Novel Indole-based Tambjamine-Analogues Induce Apoptotic Lung Cancer Cell Death through p38 Mitogen-Activated Protein Kinase Activation.

    Manuel-Manresa, Pilar; Korrodi-Gregório, Luís; Hernando, Elsa; Villanueva, Alberto; Martínez-García, David; Rodilla, Ananda M; Ramos, Ricard; Fardilha, Margarida; Moya, Juan; Quesada, Roberto; Soto-Cerrato, Vanessa; Pérez-Tomás, Ricardo

    2017-07-01

    Lung cancer has become the leading killer cancer worldwide, due to late diagnosis and lack of efficient anticancer drugs. We have recently described novel natural-derived tambjamine analogues that are potent anion transporters capable of disrupting cellular ion balance, inducing acidification of the cytosol and hyperpolarization of cellular plasma membranes. Although these tambjamine analogues were able to compromise cell survival, their molecular mechanism of action remains largely unknown. Herein we characterize the molecular cell responses induced by highly active indole-based tambjamine analogues treatment in lung cancer cells. Expression changes produced after compounds treatment comprised genes related to apoptosis, cell cycle, growth factors and its receptors, protein kinases and topoisomerases, among others. Dysregulation of BCL2 and BIRC5 /survivin genes suggested the apoptotic pathway as the induced molecular cell death mechanism. In fact, activation of several proapoptotic markers (caspase-9, caspase-3, and PARP) and reversion of the cytotoxic effect upon treatment with an apoptosis inhibitor (Z-VAD-FMK) were observed. Moreover, members of the Bcl-2 protein family suffered changes after tambjamine analogues treatment, with a concomitant protein decrease towards the prosurvival members. Besides this, it was observed cellular accumulation of ROS upon compound treatment and an activation of the stress-kinase p38 MAPK route that, when inhibited, reverted the cytotoxic effect of the tambjamine analogues. Finally, a significant therapeutic effect of these compounds was observed in subcutaneous and orthotopic lung cancer mice models. Taken together, these results shed light on the mechanism of action of novel cytotoxic anionophores and demonstrate the therapeutic effects against lung cancer. Mol Cancer Ther; 16(7); 1224-35. ©2017 AACR . ©2017 American Association for Cancer Research.

  2. Systemic Crises and Growth

    Romain Ranciere; Aaron Tornell; Frank Westermann

    2005-01-01

    In this paper, we document the fact that countries that have experienced occasional financial crises have, on average, grown faster than countries with stable financial conditions. We measure the incidence of crisis with the skewness of credit growth, and find that it has a robust negative effect on GDP growth. This link coexists with the negative link between variance and growth typically found in the literature. To explain the link between crises and growth we present a model where contract...

  3. Comparative effects of 4-phenyl-3-butenoic acid and vorinostat on cell growth and signaling.

    Burns, Timothy J; Ali, Amna; Matesic, Diane F

    2015-02-01

    4-phenyl-3-butenoic acid (PBA) is a small-molecule anti-inflammatory agent, which has been shown to inhibit growth, increase gap junction intercellular communication and modulate activation of p38 mitogen-activated protein kinase (p38 MAPK) and c-jun n-terminal kinase (JNK) in tumorigenic cells at concentrations that do not similarly affect non-tumorigenic cells. Vorinostat is an anticancer agent structurally similar to PBA. The purpose of this study was to compare the effects of these two agents on JNK and p38 activation, cell growth and gap junction intercellular communication (GJIC). Cell growth, GJIC and western blot analyses were performed utilizing tumorigenic WBras1 and H2009 human carcinoma cells, and non-tumorigenic WBneo3 and human bronchial epithelial (HBE) cells. Both compounds significantly inhibited WBras1 and H2009 tumorigenic cell growth and increased GJIC in WBras1 cells, as previously reported for PBA. Under similar conditions, both compounds increased phosphorylation of p38 MAPK in tumorigenic but not in non-tumorigenic cells and decreased phosphorylation of JNK in tumorigenic cells. However, a decrease in phosphorylation of JNK occurred in non-tumorigenic WBras1 cells following vorinostat treatment but not PBA treatment. Both compounds showed a selective growth inhibition of H2009 human carcinoma over normal HBE lung cells but, unlike PBA, vorinostat significantly decreased cell growth in WBneo3 cells. Overall, PBA exhibited similar effects to vorinostat in tumorigenic cells, while also showing reduced effects on JNK phosphorylation and growth in non-tumorigenic cells compared to ras-transformed cells. Copyright© 2015 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

  4. Urban tree growth modeling

    E. Gregory McPherson; Paula J. Peper

    2012-01-01

    This paper describes three long-term tree growth studies conducted to evaluate tree performance because repeated measurements of the same trees produce critical data for growth model calibration and validation. Several empirical and process-based approaches to modeling tree growth are reviewed. Modeling is more advanced in the fields of forestry and...

  5. Unemployment and endogenous growth

    van Schaik, A.B.T.M.; de Groot, H.L.F.

    1995-01-01

    In this paper we develop a two-sector endogenous growth model with a dual labour market, based on efficiency wages. Growth is driven by intentional R&D performed in the high-tech and high-wage sector. It is examined how a change in rivalry among firms affects simultaneously growth and unemployment.

  6. Toddler Growth and Development

    ... the AAP Schedule of Well-Child Care Visits . ​​ Toddler Growth & Development Physical Skills Walks alone Pulls toys behind when ... 18 to 23 Month Old Language Delays in Toddlers: Information for Parents ... Physical Appearance and Growth: Your 1 Year Old Physical Appearance and Growth: ...

  7. Growth Charts (For Parents)

    ... Staying Safe Videos for Educators Search English Español Growth Charts KidsHealth / For Parents / Growth Charts What's in ... Problem? Print en español Tablas de crecimiento About Growth Charts Look at any class picture, and you' ...

  8. Growth hormone, growth factors, and acromegaly

    Ludecke, D.K.; Tolis, G.T.

    1987-01-01

    This book contains five sections, each consisting of several papers. The section headings are: Biochemistry and Physiology of GH and Growth Factors, Pathology of Acromegaly, Clinical Endocrinology of Acromegaly, Nonsurgical Therapy of Acromegaly, and Surgical Therapy of Acromegaly.

  9. RNA interference-based (RNAi) suppression of AtMPK6, an Arabidopsis mitogen-activated protein kinase, results in hypersensitivity to ozone and misregulation of AtMPK3

    Miles, Godfrey P.; Samuel, Marcus A.; Zhang Yuelin; Ellis, Brian E.

    2005-01-01

    The recent increase in tropospheric ozone (O 3 ) concentrations promotes additional oxidative stress through the production of reactive oxygen species (ROS) in plant tissues, resulting in the activation of genes whose products enable the stressed cells to retain their integrity and function. This response is made possible by an integration of highly regulated signaling networks that mediate the perception of, and response to, this oxidative assault. In Arabidopsis thaliana, ROS-induced signaling has been shown to flow through a protein phosphorylation cascade involving the mitogen-activated protein kinases (MAPKs) AtMPK3 (MPK3) and AtMPK6 (MPK6). We found that RNAi-mediated silencing of MPK6 renders the plant more sensitive to ozone, as determined by visible leaf damage. The MPK6-RNAi genotype also displayed a more intense and prolonged activation of MPK3 compared to that of WT plants. An MPK3 loss-of-function genotype is similarly very sensitive to ozone, and displays an abnormally prolonged MPK6 activation profile, suggesting reciprocity in regulation between these two MAPKs. - MPK6 is pivotal in the overall response to oxidative stress and regulation of MPK3 in Arabidopsis thaliana

  10. Short communication: Camel milk ameliorates inflammatory responses and oxidative stress and downregulates mitogen-activated protein kinase signaling pathways in lipopolysaccharide-induced acute respiratory distress syndrome in rats.

    Zhu, Wei-Wei; Kong, Gui-Qing; Ma, Ming-Ming; Li, Yan; Huang, Xiao; Wang, Li-Peng; Peng, Zhen-Yi; Zhang, Xiao-Hua; Liu, Xiang-Yong; Wang, Xiao-Zhi

    2016-01-01

    Acute respiratory distress syndrome (ARDS) is a complex syndrome disorder with high mortality rate. Camel milk (CM) contains antiinflammatory and antioxidant properties and protects against numerous diseases. This study aimed to demonstrate the function of CM in lipopolysaccharide (LPS)-induced ARDS in rats. Camel milk reduced the lung wet:dry weight ratio and significantly reduced LPS-induced increases in neutrophil infiltration, interstitial and intra-alveolar edema, thickness of the alveolar wall, and lung injury scores of lung tissues. It also had antiinflammatory and antioxidant effects on LPS-induced ARDS. After LPS stimulation, the levels of proinflammatory cytokines (tumor necrosis factor-α, IL-10, and IL-1β) in serum and oxidative stress markers (malondialdehyde, myeloperoxidase, and total antioxidant capacity) in lung tissue were notably attenuated by CM. Camel milk also downregulated mitogen-activated protein kinase signaling pathways. Given these results, CM is a potential complementary food for ARDS treatment. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  11. Lipoxin A4 regulates expression of the estrogen receptor and inhibits 17β-estradiol induced p38 mitogen-activated protein kinase phosphorylation in human endometriotic stromal cells.

    Chen, Shuo; Wu, Rong-Feng; Su, Lin; Zhou, Wei-Dong; Zhu, Mao-Bi; Chen, Qiong-Hua

    2014-07-01

    To study the role of lipoxin A4 (LXA4) in endometriosis. Molecular analysis in human samples and primary human endometriotic stromal cells (ESCs). University hospital. Forty-nine premenopausal women (30 patients with endometriosis and 19 controls). Normal and ectopic endometrial biopsies obtained during surgery performed during the proliferative phase of the menstrual cycle; ESCs used for in vitro studies. Levels of LXA4 measured by enzyme-linked immunosorbent assay (ELISA); mRNA levels of the estrogen receptor (ER), progestogen receptor (PR), tumor necrosis factor α (TNF-α), and interleukin 6 (IL-6) quantified by quantitative reverse-transcription polymerase chain reaction (qRT-PCR); and p38 mitogen-activated protein kinase (p38 MAPK) phosphorylation evaluated by Western blotting. The LXA4 expression level decreased in ectopic tissue as well as ERα and PR, although the expression of ERβ increased in ectopic endometrium compared with the controls. Investigations with correlation analysis revealed the expression of LXA4 was positively correlated with ERα and negatively correlated with ERβ in vivo. Moreover, administering LXA4 could augment ERβ expression in ESCs and inhibit the 17β-estradiol-induced phosphorylation of p38 MAPK very likely through ERβ. Our findings indicate that LXA4 regulates ERβ expression and inhibits 17β-estradiol-induced phosphorylation of p38 MAPK, very likely through ERβ in ESCs. Copyright © 2014. Published by Elsevier Inc.

  12. Human tonsillar IgE biosynthesis in vitro. I. Enhancement of IgE and IgG synthesis in the presence of pokeweed mitogen by T-cell irradiation

    Ohta, K.; Manzara, T.; Harbeck, R.J.; Kirkpatrick, C.H.

    1982-01-01

    A study of the events regulating human IgE biosynthesis in vitro was undertaken with tonsillar lymphocytes. IgG synthesis was also studied to evaluate the specificity of our observations. T-cell irradiation significantly enhanced synthesis of IgE by pokeweed mitogen (PWM)-stimulated B cells from 12 of 18 donors and IgG in all 18 donors. This enhancement was the result of de novo immunoglobulin synthesis, since the amount of IgE and IgG spontaneously released from lysed and lysed-and-cultured mononuclear cells was significantly less than that detected in the cell cultures, and the augmentation was completely ablated by the treatment of the cells with cycloheximide or mitomycin C. Enhancement was also dependent on the presence of PWM; T-cell irradiation did not enhance IgE synthesis in unstimulated cultures. Moreover, this enhancement was also observed in the co-cultures of B cells and allogeneic irradiated T cells. These observations suggest that radiosensitive T cells exert a suppressive activity that contributes to regulation of human IgE and IgG synthesis and that the suppressor function as well as the helper function can overcome allogeneic disparities

  13. p38 mitogen-activated protein kinase (p38MAPK) upregulates catalase levels in response to low dose H2O2 treatment through enhancement of mRNA stability.

    Sen, Prosenjit; Chakraborty, Prabir Kumar; Raha, Sanghamitra

    2005-08-15

    V79 fibroblasts were repetitively stressed through multiple exposures to a low dose (30 microM) H2O2 in culture for 4 weeks. Catalase activity, protein levels and mRNA levels increased markedly (5-6-fold) during this time and these augmentations were inhibited by the simultaneous presence of SB203580, an inhibitor of p38 mitogen-activated protein kinase (p38MAPK). p38MAPK became dually phosphorylated and ATF-2, a p38MAPK substrate also became increasingly phosphorylated over the repetitive stress period. Short interfering RNA that induced effective silencing of p38MAPK, was used to silence p38MAPK in V79 fibroblasts. Silencing of p38MAPK drastically hindered the elevation in catalase (protein and mRNA) levels observed after a single low dose (50 microM) of H2O. The rise in catalase mRNA levels induced by low concentration (single and multiple dose) H2O2 treatment was established to be unconnected with transcriptional upregulation but was brought forth primarily by an enhancement in catalase mRNA stability through the action of p38MAPK. Therefore, our data strongly indicate that activation of p38MAPK is a key controlling step in the upregulation of catalase levels by low dose H2O2 treatment.

  14. Scaffold Protein Ahk1, Which Associates with Hkr1, Sho1, Ste11, and Pbs2, Inhibits Cross Talk Signaling from the Hkr1 Osmosensor to the Kss1 Mitogen-Activated Protein Kinase

    Nishimura, Akiko; Yamamoto, Katsuyoshi; Oyama, Masaaki; Kozuka-Hata, Hiroko

    2016-01-01

    In the budding yeast Saccharomyces cerevisiae, osmostress activates the Hog1 mitogen-activated protein kinase (MAPK), which regulates diverse osmoadaptive responses. Hkr1 is a large, highly glycosylated, single-path transmembrane protein that is a putative osmosensor in one of the Hog1 upstream pathways termed the HKR1 subbranch. The extracellular region of Hkr1 contains both a positive and a negative regulatory domain. However, the function of the cytoplasmic domain of Hkr1 (Hkr1-cyto) is unknown. Here, using a mass spectrometric method, we identified a protein, termed Ahk1 (Associated with Hkr1), that binds to Hkr1-cyto. Deletion of the AHK1 gene (in the absence of other Hog1 upstream branches) only partially inhibited osmostress-induced Hog1 activation. In contrast, Hog1 could not be activated by constitutively active mutants of the Hog1 pathway signaling molecules Opy2 or Ste50 in ahk1Δ cells, whereas robust Hog1 activation occurred in AHK1+ cells. In addition to Hkr1-cyto binding, Ahk1 also bound to other signaling molecules in the HKR1 subbranch, including Sho1, Ste11, and Pbs2. Although osmotic stimulation of Hkr1 does not activate the Kss1 MAPK, deletion of AHK1 allowed Hkr1 to activate Kss1 by cross talk. Thus, Ahk1 is a scaffold protein in the HKR1 subbranch and prevents incorrect signal flow from Hkr1 to Kss1. PMID:26787842

  15. Bacteroides fragilis Enterotoxin Induces Formation of Autophagosomes in Endothelial Cells but Interferes with Fusion with Lysosomes for Complete Autophagic Flux through a Mitogen-Activated Protein Kinase-, AP-1-, and C/EBP Homologous Protein-Dependent Pathway.

    Ko, Su Hyuk; Jeon, Jong Ik; Myung, Hyun Soo; Kim, Young-Jeon; Kim, Jung Mogg

    2017-10-01

    Bacteroides fragilis enterotoxin (BFT), a virulence factor of enterotoxigenic B. fragilis (ETBF), plays an essential role in mucosal inflammation. Although autophagy contributes to the pathogenesis of diverse infectious diseases, little is known about autophagy in ETBF infection. This study was conducted to investigate the role of BFT in the autophagic process in endothelial cells (ECs). Stimulation of human umbilical vein ECs (HUVECs) with BFT increased light chain 3 protein II (LC3-II) conversion from LC3-I and protein expression of p62, Atg5, and Atg12. In addition, BFT-exposed ECs showed increased indices of autophagosomal fusion with lysosomes such as LC3-lysosome-associated protein 2 (LAMP2) colocalization and the percentage of red vesicles monitored by the expression of dual-tagged LC3B. BFT also upregulated expression of C/EBP homologous protein (CHOP), and inhibition of CHOP significantly increased indices of autophagosomal fusion with lysosomes. BFT activated an AP-1 transcription factor, in which suppression of AP-1 activity significantly downregulated CHOP and augmented autophagosomal fusion with lysosomes. Furthermore, suppression of Jun N-terminal protein kinase (JNK) mitogen-activated protein kinase (MAPK) significantly inhibited the AP-1 and CHOP signals, leading to an increase in autophagosomal fusion with lysosomes in BFT-stimulated ECs. These results suggest that BFT induced accumulation of autophagosomes in ECs, but activation of a signaling pathway involving JNK, AP-1, and CHOP may interfere with complete autophagy. Copyright © 2017 American Society for Microbiology.

  16. Uncaria rhynchophylla inhibits the production of nitric oxide and interleukin-1β through blocking nuclear factor κB, Akt, and mitogen-activated protein kinase activation in macrophages.

    Kim, Ji-Hee; Bae, Chang Hwan; Park, Sun Young; Lee, Sang Joon; Kim, YoungHee

    2010-10-01

    The stems with hook of Uncaria rhynchophylla have been used in traditional medicine as an antipyretic, antihypertensive, and anticonvulsant in China and Korea. In this study, we investigated the mechanism responsible for anti-inflammatory effects of U. rhynchophylla in RAW 264.7 macrophages. The aqueous extract of U. rhynchophylla inhibited lipopolysaccharide (LPS)-induced nitric oxide (NO) and interleukin (IL)-1β secretion as well as inducible NO synthase (iNOS) expression, without affecting cell viability. Furthermore, U. rhynchophylla suppressed LPS-induced nuclear factor κB (NF-κB) activation, phosphorylation, and degradation of inhibitory protein IκB (IκB)-α, phosphorylation of Akt, extracellular signal-regulated kinase 1/2, p38 kinase, and c-Jun N-terminal kinase. These results suggest that U. rhynchophylla has the inhibitory effects on LPS-induced NO and IL-1β production in macrophages through blockade in the phosphorylation of Akt and mitogen-activated protein kinases, following IκB-α degradation and NF-κB activation.

  17. A Member of the p38 Mitogen-Activated Protein Kinase Family Is Responsible for Transcriptional Induction of Dopa decarboxylase in the Epidermis of Drosophila melanogaster during the Innate Immune Response▿ †

    Davis, Monica M.; Primrose, David A.; Hodgetts, Ross B.

    2008-01-01

    Drosophila innate immunity is controlled primarily by the activation of IMD (immune deficiency) or Toll signaling leading to the production of antimicrobial peptides (AMPs). IMD signaling also activates the JUN N-terminal kinase (JNK) cascade, which is responsible for immune induction of non-antimicrobial peptide immune gene transcription though the transcription factor AP-1. Transcription of the Dopa decarboxylase (Ddc) gene is induced in response to gram-negative and gram-positive septic injury, but not aseptic wounding. Transcription is induced throughout the epidermis and not specifically at the site of infection. Ddc transcripts are detectible within 2 h and remain high for several hours following infection with either gram-negative or gram-positive bacteria. Using Ddc-green fluorescent protein (GFP) reporter gene constructs, we show that a conserved consensus AP-1 binding site upstream of the Ddc transcription start site is required for induction. However, neither the Toll, IMD, nor JNK pathway is involved. Rather, Ddc transcription depends on a previously uncharacterized member of the p38 mitogen-activated protein kinase family, p38c. We propose that the involvement of DDC in a new pathway involved in Drosophila immunity increases the levels of dopamine, which is metabolized to produce reactive quinones that exert an antimicrobial effect on invading bacteria. PMID:18519585

  18. The Histone Deacetylase Inhibitors MS-275 and SAHA Suppress the p38 Mitogen-Activated Protein Kinase Signaling Pathway and Chemotaxis in Rheumatoid Arthritic Synovial Fibroblastic E11 Cells

    Hai-Shu Lin

    2013-11-01

    Full Text Available MS-275 (entinostat and SAHA (vorinostat, two histone deacetylase (HDAC inhibitors currently in oncological trials, have displayed potent anti-rheumatic activities in rodent models of rheumatoid arthritis (RA. To further elucidate their anti-inflammatory mechanisms, the impact of MS-275 and SAHA on the p38 mitogen-activated protein kinase (MAPK signaling pathway and chemotaxis was assessed in human rheumatoid arthritic synovial fibroblastic E11 cells. MS-275 and SAHA significantly suppressed the expression of p38α  MAPK, but induced the expression of MAPK phosphatase-1 (MKP-1, an endogenous suppressor of p38α  in E11 cells. At the same time, the association between p38α and MKP-1 was up-regulated and consequently, the activation (phosphorylation of p38α  was inhibited. Moreover, MS-275 and SAHA suppressed granulocyte chemotactic protein-2 (GCP-2, monocyte chemotactic protein-2 (MCP-2 and macrophage migration inhibitory factor (MIF in E11 cells in a concentration-dependent manner. Subsequently, E11-driven migration of THP-1 and U937 monocytes was inhibited. In summary, suppression of the p38 MAPK signaling pathway and chemotaxis appear to be important anti-rheumatic mechanisms of action of these HDAC inhibitors.

  19. Lung growth and development.

    Joshi, Suchita; Kotecha, Sailesh

    2007-12-01

    Human lung growth starts as a primitive lung bud in early embryonic life and undergoes several morphological stages which continue into postnatal life. Each stage of lung growth is a result of complex and tightly regulated events governed by physical, environmental, hormonal and genetic factors. Fetal lung liquid and fetal breathing movements are by far the most important determinants of lung growth. Although timing of the stages of lung growth in animals do not mimic that of human, numerous animal studies, mainly on sheep and rat, have given us a better understanding of the regulators of lung growth. Insight into the genetic basis of lung growth has helped us understand and improve management of complex life threatening congenital abnormalities such as congenital diaphragmatic hernia and pulmonary hypoplasia. Although advances in perinatal medicine have improved survival of preterm infants, premature birth is perhaps still the most important factor for adverse lung growth.

  20. Human Chorionic Gonadotrophin as a Possible Mediator of Leiomyoma Growth during Pregnancy: Molecular Mechanisms.

    Sarais, Veronica; Cermisoni, Greta Chiara; Schimberni, Matteo; Alteri, Alessandra; Papaleo, Enrico; Somigliana, Edgardo; Vigano', Paola

    2017-09-20

    Uterine fibroids are the most common gynecologic benign tumors. Studies supporting a strong pregnancy-related growth of leiomyomas generally claimed a crucial role of sex steroid hormones. However, sex steroids are unlikely the unique actors involved as estrogen and progesterone achieve a pick serum concentration in the last trimester while leiomyomas show a typical increase during the first trimester. Given the rapid exponential raise in serum human Chorionic Gonadotrophin (hCG) at the beginning of gestation, we conducted a review to assess the potential role of hCG in the striking growth of leiomyomas during initial pregnancy. Fibroid growth during initial pregnancy seems to correlate to the similar increase of serum hCG levels until 12 weeks of gestation. The presence of functional Luteinizing Hormone/human Chorionic Gonadotropin (LH/hCG) receptors was demonstrated on leiomyomas. In vitro treatment of leiomyoma cells with hCG determines an up to 500% increase in cell number after three days. Expression of cyclin E and cyclin-dependent kinase 1 was significantly increased in leiomyoma cells by hCG treatment. Moreover, upon binding to the receptor, hCG stimulates prolactin secretion in leiomyoma cells, promoting cell proliferation via the mitogen-activated protein kinase cascade. Fibroid enlargement during initial pregnancy may be regulated by serum hCG.

  1. Inhibitors of the epidermal growth factor receptor in apple juice extract.

    Kern, Melanie; Tjaden, Zeina; Ngiewih, Yufanyi; Puppel, Nicole; Will, Frank; Dietrich, Helmut; Pahlke, Gudrun; Marko, Doris

    2005-04-01

    The polyphenol-rich extract of a consumer-relevant apple juice blend was found to potently inhibit the growth of the human colon cancer cell line HT29 in vitro. The epidermal growth factor receptor (EGFR) and its subsequent signaling cascade play an important role in the regulation of cell proliferation in HT29 cells. The protein tyrosine kinase activity of an EGFR preparation was effectively inhibited by the polyphenol-rich apple juice extract. Treatment of intact cells with this extract resulted in the suppression of the subsequent mitogen-activated protein kinase cascade. Amongst the so far identified apple juice constituents, the proanthocyanidins B1 and B2 as well as quercetin-3-glc (isoquercitrin) and quercetin-3-gal (hyperoside) were found to possess substantial EGFR-inhibitory properties. However, as to be expected from the final concentration of these potential EGFR inhibitors in the original polyphenol-rich extract, a synthetic mixture of the apple juice constituents identified and available so far, including both proanthocyanidins and the quercetin glycosides, showed only marginal inhibitory effects on the EGFR. These results permit the assumption that yet unknown constituents contribute substantially to the potent EGFR-inhibitory properties of polyphenol-rich apple juice extract. In summary, the polyphenol composition of apple juice possesses promising growth-inhibitory properties, affecting proliferation-associated signaling cascades in colon tumor cells.

  2. Prioritizing plant defence over growth through WRKY regulation facilitates infestation by non-target herbivores

    Li, Ran; Zhang, Jin; Li, Jiancai; Zhou, Guoxin; Wang, Qi; Bian, Wenbo; Erb, Matthias; Lou, Yonggen

    2015-01-01

    Plants generally respond to herbivore attack by increasing resistance and decreasing growth. This prioritization is achieved through the regulation of phytohormonal signaling networks. However, it remains unknown how this prioritization affects resistance against non-target herbivores. In this study, we identify WRKY70 as a specific herbivore-induced, mitogen-activated protein kinase-regulated rice transcription factor that physically interacts with W-box motifs and prioritizes defence over growth by positively regulating jasmonic acid (JA) and negatively regulating gibberellin (GA) biosynthesis upon attack by the chewing herbivore Chilo suppressalis. WRKY70-dependent JA biosynthesis is required for proteinase inhibitor activation and resistance against C. suppressalis. In contrast, WRKY70 induction increases plant susceptibility against the rice brown planthopper Nilaparvata lugens. Experiments with GA-deficient rice lines identify WRKY70-dependent GA signaling as the causal factor in N. lugens susceptibility. Our study shows that prioritizing defence over growth leads to a significant resistance trade-off with important implications for the evolution and agricultural exploitation of plant immunity. DOI: http://dx.doi.org/10.7554/eLife.04805.001 PMID:26083713

  3. Azadirachtin Affects the Growth of Spodoptera litura Fabricius by Inducing Apoptosis in Larval Midgut.

    Shu, Benshui; Zhang, Jingjing; Cui, Gaofeng; Sun, Ranran; Yi, Xin; Zhong, Guohua

    2018-01-01

    Azadirachtin, the environmentally friendly botanical pesticide, has been used as an antifeedant and pest growth regulator in integrated pest management for decades. It has shown strong biological activity against Spodoptera litura , but the mechanism of toxicity remains unclear. The present study showed that azadirachtin inhibited the growth of S. litura larvae, which was resulted by structure destroy and size inhibition of the midgut. Digital gene expression (DGE) analysis of midgut suggested that azadirachtin regulated the transcriptional level of multiple unigenes involved in mitogen-activated protein kinase (MAPK) and calcium apoptotic signaling pathways. Simultaneously, the expression patterns of some differentially expressed unigenes were verified by quantitative real time-PCR (qRT-PCR). In addition, the enhanced terminal deoxynucleotidyl transferase biotin-dUTP nick end labeling (TUNEL) staining, the increased expression of caspase family members and apoptosis-binding motif 1 (IBM1) on both gene and protein level and the release of cytochrome c from mitochondria to cytoplasm were induced in midgut after azadirachtin treatment. These results demonstrated that azadirachtin induced structural alteration in S. litura larval midgut by apoptosis activation. These alterations may affect the digestion and absorption of nutrients and eventually lead to the growth inhibition of larvae.

  4. Azadirachtin Affects the Growth of Spodoptera litura Fabricius by Inducing Apoptosis in Larval Midgut

    Benshui Shu

    2018-02-01

    Full Text Available Azadirachtin, the environmentally friendly botanical pesticide, has been used as an antifeedant and pest growth regulator in integrated pest management for decades. It has shown strong biological activity against Spodoptera litura, but the mechanism of toxicity remains unclear. The present study showed that azadirachtin inhibited the growth of S. litura larvae, which was resulted by structure destroy and size inhibition of the midgut. Digital gene expression (DGE analysis of midgut suggested that azadirachtin regulated the transcriptional level of multiple unigenes involved in mitogen-activated protein kinase (MAPK and calcium apoptotic signaling pathways. Simultaneously, the expression patterns of some differentially expressed unigenes were verified by quantitative real time-PCR (qRT-PCR. In addition, the enhanced terminal deoxynucleotidyl transferase biotin-dUTP nick end labeling (TUNEL staining, the increased expression of caspase family members and apoptosis-binding motif 1 (IBM1 on both gene and protein level and the release of cytochrome c from mitochondria to cytoplasm were induced in midgut after azadirachtin treatment. These results demonstrated that azadirachtin induced structural alteration in S. litura larval midgut by apoptosis activation. These alterations may affect the digestion and absorption of nutrients and eventually lead to the growth inhibition of larvae.

  5. Association of Vascular Endothelial Growth Factor Expression with Tumor Angiogenesis and with Early Relapse in Primary Breast Cancer

    Hoshina, Seigo; Takayanagi, Toshiaki; Tominaga, Takeshi

    1994-01-01

    Angiogenesis is an independent prognostic indicator in breast cancer. In this report, the relationship between expression of vascular endothclial growth factor (VEGF; a selective mitogen for endothelial cells) and the microvessel density was examined in 103 primary breast cancers. The expression of VEGF was evaluated by immunocytochemical staining using anti‐VEGF antibody. The microvessel density, which was determined by immunostaining for factor VIII antigen, in VEGF‐rich tumors was clearly higher than that in VEGF‐poor tumors (P<0.01). There was a good correlation between VEGF expression and the increment of microvessel density. Furthermore, postoperative survey demonstrated that the relapse‐free survival rate of VEGF‐rich tumors was significantly worse than that of VEGF‐poor tumors. It was suggested that the expression of VEGF is closely associated with the promotion of angiogenesis and with early relapse in primary breast cancer. PMID:7525523

  6. Reserve growth in German oilfields; Reservenwachstum in deutschen Erdoelfeldern

    Schwietzer, Curt-Albert [RWE Dea AG, Hamburg (Germany)

    2013-07-15

    In the English language use, the term ''Reserve Growth'' describes the fact that in most cases at the start of a field development the estimated ultimate recovery of reserves (EUR) is smaller than it will turn out later by production history. Although this phenomenon of reserve growth gives hints for new reserves in mature hydrocarbon provinces, it has hardly been investigated. In the few existing studies about this issue it is shown that reserve growth is, in the majority of cases, based on factors like the application of improved methods to increase the recovery factor as well as on optimization of the reservoir development by precise modeling and simulation as well as on changing of the reserve classification. Different combinations of these factors affect the changes of reserves during the life of the reservoir. This study investigates the reserve trend of 35 German oilfields over the last 40 to 50 years. Most of them register reserve growth; in some cases even a factor > 10 was achieved. On average, this reserve growth factor can be calculated as 3. A similar study about US American onshore oilfields was carried out for the first time by Arrington; this was, at a later time, revised by the USGS. In the article, Mahendra K. Verma developed the ''Growth Function'' by regression. The ''Growth Function'' describes the changes of proved reserves during the life of an oil reservoir. It indicates that ten years after production start, the reserves increased by three times, whereas the largest proportion of this increase occurred in the first three years. During the next 30 years, the reserves growth factor increased by up to 5.3; at the point of 95 years of production it accumulated to 6.9. In the case of the analysed German oilfields, the reserve growth behaviour was similar. Corresponding to the ''Growth Function'' after 40 years of production, it achieved a factor of 5 and reached a

  7. Adaptive growth factor delivery from a polyelectrolyte coating promotes synergistic bone tissue repair and reconstruction

    Shah, Nisarg J.; Hyder, Md. Nasim; Quadir, Mohiuddin A.; Dorval Courchesne, Noémie-Manuelle; Seeherman, Howard J.; Nevins, Myron; Spector, Myron; Hammond, Paula T.

    2014-01-01

    Traumatic wounds and congenital defects that require large-scale bone tissue repair have few successful clinical therapies, particularly for craniomaxillofacial defects. Although bioactive materials have demonstrated alternative approaches to tissue repair, an optimized materials system for reproducible, safe, and targeted repair remains elusive. We hypothesized that controlled, rapid bone formation in large, critical-size defects could be induced by simultaneously delivering multiple biological growth factors to the site of the wound. Here, we report an approach for bone repair using a polyelectrolye multilayer coating carrying as little as 200 ng of bone morphogenetic protein-2 and platelet-derived growth factor-BB that were eluted over readily adapted time scales to induce rapid bone repair. Based on electrostatic interactions between the polymer multilayers and growth factors alone, we sustained mitogenic and osteogenic signals with these growth factors in an easily tunable and controlled manner to direct endogenous cell function. To prove the role of this adaptive release system, we applied the polyelectrolyte coating on a well-studied biodegradable poly(lactic-co-glycolic acid) support membrane. The released growth factors directed cellular processes to induce bone repair in a critical-size rat calvaria model. The released growth factors promoted local bone formation that bridged a critical-size defect in the calvaria as early as 2 wk after implantation. Mature, mechanically competent bone regenerated the native calvaria form. Such an approach could be clinically useful and has significant benefits as a synthetic, off-the-shelf, cell-free option for bone tissue repair and restoration. PMID:25136093

  8. Fetal antigen 1, a member of the epidermal growth factor superfamily, in neurofibromas and serum from patients with neurofibromatosis type 1

    Jensen, Charlotte Harken; Schroder, H D; Teisner, B

    1999-01-01

    Fetal antigen 1 (FA1) is a 26-32 kDa glycoprotein containing six epidermal growth factor-like repeats closely related to the delta/notch/serrate proteins in Drosophila. FA1 has been shown to be involved in cell differentiation in a juxtacrine/paracrine manner. As neurofibromatosis type 1 (NF-1......), also called von Recklinghausen disease, involves aberrant growth of tissues derived from the neural crest, the expression of FA1 was examined in neurofibroma skin biopsies and serum from patients with NF-1. FA1 was found in the spindle cells of all (n = 10) skin tumour specimens from adult NF-1...

  9. Cell-cell adhesion mediated by binding of membrane-anchored transforming growth factor α to epidermal growth factor receptors promotes cell proliferation

    Anklesaria, P.; Greenberger, J.S.; Teixido, J.; Laiho, M.; Massague, J.; Pierce, J.H.

    1990-01-01

    The precursor for transforming growth factor α, pro-TGF-α, is a cell surface glycoprotein that can establish contact with epidermal growth factor (EGF) receptors on adjacent cells. To examine whether the pro-TGF-α/EGF receptor pair can simultaneously mediate cell adhesion and promote cell proliferation, the authors have expressed pro-TGF-α in a bone marrow stromal cell line labeled with [ 35 S] cysteine. Expression of pro-TGF-α allows these cells to support long-term attachment of an EGF/interleukin-3-dependent hematopoietic progenitor cell line that expresses EGF receptors but is unable to adhere to normal stroma. This interaction is inhibited by soluble EGF receptor ligands. Further, the hematopoietic progenitor cells replicate their DNA while they are attached to the stromal cell layer and become foci of sustained cell proliferation. Thus, pro-TGF-α and the EGF receptor can function as mediators of intercellular adhesion and this interaction may promote a mitogenic response. They propose the term juxtacrine to designate this form of stimulation between adjacent cells

  10. Adult growth hormone deficiency

    Vishal Gupta

    2011-01-01

    Full Text Available Adult growth hormone deficiency (AGHD is being recognized increasingly and has been thought to be associated with premature mortality. Pituitary tumors are the commonest cause for AGHD. Growth hormone deficiency (GHD has been associated with neuropsychiatric-cognitive, cardiovascular, neuromuscular, metabolic, and skeletal abnormalities. Most of these can be reversed with growth hormone therapy. The insulin tolerance test still remains the gold standard dynamic test to diagnose AGHD. Growth hormone is administered subcutaneously once a day, titrated to clinical symptoms, signs and IGF-1 (insulin like growth factor-1. It is generally well tolerated at the low-doses used in adults. Pegylated human growth hormone therapy is on the horizon, with a convenient once a week dosing.

  11. Aid and growth regressions

    Hansen, Henrik; Tarp, Finn

    2001-01-01

    This paper examines the relationship between foreign aid and growth in real GDP per capita as it emerges from simple augmentations of popular cross country growth specifications. It is shown that aid in all likelihood increases the growth rate, and this result is not conditional on ‘good’ policy....... investment. We conclude by stressing the need for more theoretical work before this kind of cross-country regressions are used for policy purposes.......This paper examines the relationship between foreign aid and growth in real GDP per capita as it emerges from simple augmentations of popular cross country growth specifications. It is shown that aid in all likelihood increases the growth rate, and this result is not conditional on ‘good’ policy...

  12. City Population Growth and Economic Growth

    Freire-Gibb, L. Carlos

    2008-01-01

    This article looks at the relationship between city population growth (intimately related to population proximity), and economic development. The hypothesis is that wherever dynamic and inclusive networks exist, there are more opportunities for economic development in this place. When these types...... of networks choose a tool (project, policy) to implement in the city, success will be more likely. Furthermore, virtuous circles will arise. The author gives an overview of two historical cases in urban growth, in Europe (1200-1800) and the U.S.A. (1800 to today)....

  13. Earthquakes and economic growth

    Fisker, Peter Simonsen

    2012-01-01

    This study explores the economic consequences of earthquakes. In particular, it is investigated how exposure to earthquakes affects economic growth both across and within countries. The key result of the empirical analysis is that while there are no observable effects at the country level, earthquake exposure significantly decreases 5-year economic growth at the local level. Areas at lower stages of economic development suffer harder in terms of economic growth than richer areas. In addition,...

  14. Luxury-based Growth

    Shiro Kuwahara

    2006-01-01

    Assuming that there exists a preference for luxury goods and a knowledge spillover from luxury goods production to goods production, this paper constructs an endogenous economic growth model. The model predicts two steady states: one is a steady positive growth state with regard to luxury goods production, and the other is a zero growth state in the absence of luxury goods production. Thus, this study examines the polarization of economies based on luxury goods consumption

  15. Robust Growth Determinants

    Doppelhofer, Gernot; Weeks, Melvyn

    2011-01-01

    This paper investigates the robustness of determinants of economic growth in the presence of model uncertainty, parameter heterogeneity and outliers. The robust model averaging approach introduced in the paper uses a flexible and parsi- monious mixture modeling that allows for fat-tailed errors compared to the normal benchmark case. Applying robust model averaging to growth determinants, the paper finds that eight out of eighteen variables found to be significantly related to economic growth ...

  16. Thailand's growth rebalancing

    Jitsuchon, Somchai; Sussangkarn, Chalongphob

    2009-01-01

    This paper reviews Thailand's structural changes, the 1997 crisis experience, and recovery and lessons from the crisis. The paper then discusses the impacts of the subprime crisis on the Thai economy and the policy responses to date. The paper ends by discussing strategies to rebalance growth by reducing the dependence on exports as the main growth engine. The recovery from the 1997 crisis left Thailand more dependent than ever on exports as the main engine of growth, with the ratio of export...

  17. Smart Growth and Transportation

    Describes the relationship between smart growth and transportation, focusing smart and sustainable street design, transit-oriented development, parking management, sustainable transportation planning, and related resources.

  18. FDI- Economic Growth Nexus

    Bujac, Andreea Ioana; Corado Cretu, Emanuel

    2017-01-01

    Conducting a systematic literature review on the topic of FDI and Economic Growth and investigating this relationship, along with the determinants of an economy that attract FDI and the externalities resulting from Foreign activities, it is found that FDI does have a positive effect on a host...... country’s economic growth but only with the preexistence of certain determinants which facilitate the absorption capacity of the host country on reaping the spillover effects (externalities) of FDI. Lastly, a framework was built to illustrate the interaction between FDI, Determinants and condition...... of the host economy, barriers to growth, economic growth and externalities....

  19. Aid, growth, and development

    Arndt, Channing; Jones, Edward Samuel; Tarp, Finn

    2010-01-01

    The micro-macro paradox has been revived. Despite broadly positive evaluations at the micro- and meso-levels, recent literature doubts the ability of foreign aid to foster economic growth and development. This paper assesses the aid-growth literature and, taking inspiration from the program...... evaluation literature, we re-examine key hypotheses. In our findings, aid has a positive and statistically significant causal effect on growth over the long run, with confidence intervals conforming to levels suggested by growth theory. Aid remains a key tool for enhancing the development prospects of poor...

  20. Optimising growth in phenylketonuria

    Dokoupil, Katharina; Gokmen-Ozel, Hulya; Lammardo, Anna Maria

    2012-01-01

    populations. We reviewed the literature searching for evidence regarding PKU and growth as well as possible links between dietary management of PKU and growth. The search retrieved only limited evidence on the effect of PKU and its dietary management on growth. Physical development in PKU remains an under....... Protein requirements in dietary management of PKU are met mostly from Phe-free protein substitutes with the intake of natural protein restricted to patient tolerance. Several reports have suggested that growth in early childhood in PKU is sub-optimal, relative to non-PKU control groups or reference...

  1. Triplet ultrasound growth parameters.

    Vora, Neeta L; Ruthazer, Robin; House, Michael; Chelmow, David

    2006-03-01

    To create ultrasound growth curves for normal growth of fetal triplets using statistical methodology that properly accounts for similarities of growth of fetuses within a mother as well as repeated measurements over time for each fetus. In this longitudinal study, all triplet pregnancies managed at a single tertiary center from 1992-2004 were reviewed. Fetuses with major anomalies, prior selective reduction, or fetal demise were excluded. Data from early and late gestation in which there were fewer than 30 fetal measurements available for analysis were excluded. We used multilevel models to account for variation in growth within a single fetus over time, variations in growth between multiple fetuses within a single mother, and variations in fetal growth between mothers. Medians (50th), 10th, and 90th percentiles were estimated by the creation of multiple quadratic growth models from bootstrap samples adapting a previously published method to compute prediction intervals. Estimated fetal weight was derived from Hadlock's formula. One hundred fifty triplet pregnancies were identified. Twenty-seven pregnancies were excluded for the following reasons: missing records (23), fetal demise (3), and fetal anomaly (1). The study group consisted of 123 pregnancies. The gestational age range was restricted to 14-34 weeks. Figures and tables were developed showing medians, 10th and 90th percentiles for estimated fetal weight, femur length, biparietal diameter, abdominal circumference, and head circumference. Growth curves for triplet pregnancies were derived. These may be useful for identification of abnormal growth in triplet fetuses. III.

  2. Incentives and Earnings Growth

    Frederiksen, Anders

    2013-01-01

    The career prospects of newly recruited employees differ substantially within an organization. The stars experience considerable growth in earnings; others can hardly maintain their entry salaries. This article sheds light on the mechanisms generating the observed heterogeneity in earnings growth...... by investigating the effects that explicit short-run incentives and implicit incentives have on earnings growth. The model’s predictions are tested using personnel records from a large bank and are found to be consistent with the observed earnings growth during the first half of the employees’ careers....

  3. p38 mitogen-activated protein kinase up-regulates LPS-induced NF-κB activation in the development of lung injury and RAW 264.7 macrophages

    Kim, Hee J.; Lee, Hui S.; Chong, Young H.; Kang, Jihee Lee

    2006-01-01

    Clarification of the key regulatory steps that lead to nuclear factor-kappa B (NF-κB) under cellular and pathological conditions is very important. The action of p38 mitogen-activated protein kinase (MAPK) on the upstream of NF-κB activation remains controversial. To examine this issue using an in vivo lung injury model, SB203580, a p38 MAPK inhibitor was given intraorally 1 h prior to lipopolysaccharide (LPS) treatment (intratracheally). The mice were sacrificed 4 h after LPS treatment. SB203580 substantially suppressed LPS-induced rises in p38 MAPK phosphorylation, neutrophil recruitment, total protein content in bronchoalveolar lavage fluid, and apoptosis of bronchoalveolar cells. Furthermore, SB203580 blocked LPS-induced NF-κB activation in lung tissue through down-regulation of serine phosphorylation, degradation of IκB-α, and consequent translocation of the p65 subunit of NF-κB to the nucleus. It is likely that, in cultured RAW 264.7 macrophages, SB203580 also blocked LPS-induced NF-κB activation in a dose-dependent manner. SB203580 inhibited LPS-induced serine phosphorylation, degradation of IκB-α, and tyrosine phosphorylation of p65 NF-κB. These data indicate that p38 MAPK acts upstream of LPS-induced NF-κB activation by modulating the phosphorylation of IκB-α and p65 NF-κB during acute lung injury. Because LPS-stimulated macrophages may contribute to inflammatory lung injury, the inhibition of the p38 MAPK-mediated intracellular signaling pathway leading to NF-κB activation represents a target for the attenuation of lung inflammation and parenchymal damage

  4. Progesterone increases brain-derived neuroptrophic factor expression and protects against glutamate toxicity in a mitogen-activated protein kinase- and phosphoinositide-3 kinase-dependent manner in cerebral cortical explants.

    Kaur, Paramjit; Jodhka, Parmeet K; Underwood, Wendy A; Bowles, Courtney A; de Fiebre, Nancyellen C; de Fiebre, Christopher M; Singh, Meharvan

    2007-08-15

    The higher prevalence and risk for Alzheimer's disease in women relative to men has been partially attributed to the precipitous decline in gonadal hormone levels that occurs in women following the menopause. Although considerable attention has been focused on the consequence of estrogen loss, and thus estrogen's neuroprotective potential, it is important to recognize that the menopause results in a precipitous decline in progesterone levels as well. In fact, progesterone is neuroprotective, although the precise mechanisms involved remain unclear. Based on our previous observation that progesterone elicits the phosphorylation of ERK and Akt, key effectors of the neuroprotective mitogen-activated protein kinase (MAPK) and phosphoinositide-3 kinase (PI3-K) pathways, respectively, we determined whether activation of either of these pathways was necessary for progesterone-induced protection. With organotypic explants (slice culture) of the cerebral cortex, we found that progesterone protected against glutamate-induced toxicity. Furthermore, these protective effects were inhibited by either the MEK1/2 inhibitor UO126 or the PI3-K inhibitor LY294002, supporting the requirement for both the MAPK and PI3-K pathways in progesterone-induced protection. In addition, at a concentration and duration of treatment consistent with our neuroprotection data, progesterone also increased the expression of brain-derived neurotrophic factor (BDNF), at the level of both protein and mRNA. This induction of BDNF may be relevant to the protective effects of progesterone, in that inhibition of Trk signaling, with K252a, inhibited the protective effects of progesterone. Collectively, these data suggest that progesterone is protective via multiple and potentially related mechanisms. (c) 2007 Wiley-Liss, Inc. Copyright 2007 Wiley-Liss, Inc.

  5. The pearl millet mitogen-activated protein kinase PgMPK4 is involved in responses to downy mildew infection and in jasmonic- and salicylic acid-mediated defense.

    Melvin, Prasad; Prabhu, S Ashok; Veena, Mariswamy; Shailasree, Sekhar; Petersen, Morten; Mundy, John; Shetty, Shekar H; Kini, K Ramachandra

    2015-02-01

    Plant mitogen-activated protein kinases (MPKs) transduce signals required for the induction of immunity triggered by host recognition of pathogen-associated molecular patterns. We isolated a full-length cDNA of a group B MPK (PgMPK4) from pearl millet. Autophosphorylation assay of recombinant PgMPK4 produced in Escherichia coli confirmed it as a kinase. Differential accumulation of PgMPK4 mRNA and kinase activity was observed between pearl millet cultivars 852B and IP18292 in response to inoculation with the downy mildew oomycete pathogen Sclerospora graminicola. This increased accumulation of PgMPK4 mRNA, kinase activity as well as nuclear-localization of PgMPK protein(s) was only detected in the S. graminicola resistant cultivar IP18292 with a ~tenfold peak at 9 h post inoculation. In the susceptible cultivar 852B, PgMPK4 mRNA and immuno-detectable nuclear PgMPK could be induced by application of the chemical elicitor β-amino butyric acid, the non-pathogenic bacteria Pseudomonas fluorescens, or by the phytohormones jasmonic acid (JA) or salicylic acid (SA). Furthermore, kinase inhibitor treatments indicated that PgMPK4 is involved in the JA- and SA-mediated expression of three defense genes, lipoxygenase, catalase 3 and polygalacturonase-inhibitor protein. These findings indicate that PgMPK/s contribute to pearl millet defense against the downy mildew pathogen by activating the expression of defense proteins.

  6. Enhanced expression of WD repeat-containing protein 35 (WDR35 stimulated by domoic acid in rat hippocampus: involvement of reactive oxygen species generation and p38 mitogen-activated protein kinase activation

    Tsunekawa Koji

    2013-01-01

    Full Text Available Abstract Background Domoic acid (DA is an excitatory amino acid analogue of kainic acid (KA that acts via activation of glutamate receptors to elicit a rapid and potent excitotoxic response, resulting in neuronal cell death. Recently, DA was shown to elicit reactive oxygen species (ROS production and induce apoptosis accompanied by activation of p38 mitogen-activated protein kinase (MAPK in vitro. We have reported that WDR35, a WD-repeat protein, may mediate apoptosis in several animal models. In the present study, we administered DA to rats intraperitoneally, then used liquid chromatography/ion trap tandem mass spectrometry (LC-MS/MS to identify and quantify DA in the brains of the rats and performed histological examinations of the hippocampus. We further investigated the potential involvement of glutamate receptors, ROS, p38 MAPK, and WDR35 in DA-induced toxicity in vivo. Results Our results showed that intraperitoneally administered DA was present in the brain and induced neurodegenerative changes including apoptosis in the CA1 region of the hippocampus. DA also increased the expression of WDR35 mRNA and protein in a dose- and time-dependent manner in the hippocampus. In experiments using glutamate receptor antagonists, the AMPA/KA receptor antagonist NBQX significantly attenuated the DA-induced increase in WDR35 protein expression, but the NMDA receptor antagonist MK-801 did not. In addition, the radical scavenger edaravone significantly attenuated the DA-induced increase in WDR35 protein expression. Furthermore, NBQX and edaravone significantly attenuated the DA-induced increase in p38 MAPK phosphorylation. Conclusion In summary, our results indicated that DA activated AMPA/KA receptors and induced ROS production and p38 MAPK phosphorylation, resulting in an increase in the expression of WDR35 in vivo.

  7. Syndecan-1/CD147 association is essential for cyclophilin B-induced activation of p44/42 mitogen-activated protein kinases and promotion of cell adhesion and chemotaxis.

    Pakula, Rachel; Melchior, Aurélie; Denys, Agnès; Vanpouille, Christophe; Mazurier, Joël; Allain, Fabrice

    2007-05-01

    Many of the biological functions attributed to cell surface proteoglycans are dependent on the interaction with extracellular mediators through their heparan sulphate (HS) moieties and the participation of their core proteins in signaling events. A class of recently identified inflammatory mediators is secreted cyclophilins, which are mostly known as cyclosporin A-binding proteins. We previously demonstrated that cyclophilin B (CyPB) triggers chemotaxis and integrin-mediated adhesion of T lymphocytes mainly of the CD4+/CD45RO+ phenotype. These activities are related to interactions with two types of binding sites, CD147 and cell surface HS. Here, we demonstrate that CyPB-mediated adhesion of CD4+/CD45RO+ T cells is related to p44/42 mitogen-activated protein kinase (MAPK) activation by a mechanism involving CD147 and HS proteoglycans (HSPG). Although HSPG core proteins are represented by syndecan-1, -2, -4, CD44v3 and betaglycan in CD4+/CD45RO+ T cells, we found that only syndecan-1 is physically associated with CD147. The intensity of the heterocomplex increased in response to CyPB, suggesting a transient enhancement and/or stabilization in the association of CD147 to syndecan-1. Pretreatment with anti-syndecan-1 antibodies or knockdown of syndecan-1 expression by RNA interference dramatically reduced CyPB-induced p44/p42 MAPK activation and consequent migration and adhesion, supporting the model in which syndecan-1 serves as a binding subunit to form the fully active receptor of CyPB. Altogether, our findings provide a novel example of a soluble mediator in which a member of the syndecan family plays a critical role in efficient interaction with signaling receptors and initiation of cellular responses.

  8. Mitogen activated protein kinase kinase kinase 3 (MAP3K3/MEKK3) overexpression is an early event in esophageal tumorigenesis and is a predictor of poor disease prognosis

    Hasan, Raghibul; Sharma, Rinu; Saraya, Anoop; Chattopadhyay, Tushar K; DattaGupta, Siddartha; Walfish, Paul G; Chauhan, Shyam S; Ralhan, Ranju

    2014-01-01

    Mitogen-activated protein kinase kinase kinase3 (MAP3K3/MEKK3) was identified to be differentially expressed in esophageal squamous cell carcinoma (ESCC) using cDNA microarrays by our laboratory. Here in we determined the clinical significance of MEKK3 in ESCC. Immunohistochemical analysis of MEKK3 expression was carried out in archived tissue sections from 93 ESCCs, 47 histologically normal and 61 dysplastic esophageal tissues and correlated with clinicopathological parameters and disease prognosis over up to 7.5 years for ESCC patients. MEKK3 expression was significantly increased in esophageal dysplasia and ESCC in comparison with normal mucosa (p trend < 0.001). Kaplan Meier survival analysis showed significantly reduced median disease free survival median DFS = 10 months in patients with MEKK3 positive ESCCs compared to patients with no immunopositivity (median DFS = 19 months, p = 0.04). ESCC patients with MEKK3 positive and lymph node positive tumors had median DFS = 9 months, as compared to median DFS = 21 months in patients who did not show the alterations (p = 0.01). In multivariate Cox regression analysis, combination of MEKK3 overexpression and node positivity [p = 0.015, hazard ratio (HR) = 2.082, 95% CI = 1.154 - 3.756] emerged as important predictor of reduced disease free survival and poor prognosticator for ESCC patients. Alterations in MEKK3 expression occur in early stages of development of ESCC and are sustained during disease progression; MEKK3 in combination with lymph node positivity has the potential to serve as adverse prognosticator in ESCC

  9. The p38 mitogen-activated protein kinase signaling pathway is involved in regulating low-density lipoprotein receptor-related protein 1-mediated β-amyloid protein internalization in mouse brain.

    Ma, Kai-Ge; Lv, Jia; Hu, Xiao-Dan; Shi, Li-Li; Chang, Ke-Wei; Chen, Xin-Lin; Qian, Yi-Hua; Yang, Wei-Na; Qu, Qiu-Min

    2016-07-01

    Alzheimer's disease (AD) is one of the most common neurodegenerative diseases. Recently, increasing evidence suggests that intracellular β-amyloid protein (Aβ) alone plays a pivotal role in the progression of AD. Therefore, understanding the signaling pathway and proteins that control Aβ internalization may provide new insight for regulating Aβ levels. In the present study, the regulation of Aβ internalization by p38 mitogen-activated protein kinases (MAPK) through low-density lipoprotein receptor-related protein 1 (LRP1) was analyzed in vivo. The data derived from this investigation revealed that Aβ1-42 were internalized by neurons and astrocytes in mouse brain, and were largely deposited in mitochondria and lysosomes, with some also being found in the endoplasmic reticulum. Aβ1-42-LRP1 complex was formed during Aβ1-42 internalization, and the p38 MAPK signaling pathway was activated by Aβ1-42 via LRP1. Aβ1-42 and LRP1 were co- localized in the cells of parietal cortex and hippocampus. Furthermore, the level of LRP1-mRNA and LRP1 protein involved in Aβ1-42 internalization in mouse brain. The results of this investigation demonstrated that Aβ1-42 induced an LRP1-dependent pathway that related to the activation of p38 MAPK resulting in internalization of Aβ1-42. These results provide evidence supporting a key role for the p38 MAPK signaling pathway which is involved in the regulation of Aβ1-42 internalization in the parietal cortex and hippocampus of mouse through LRP1 in vivo. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. Evaluation of the potential immunotoxicity of 3-monochloro-1,2-propanediol in Balb/c mice I. Effect on antibody forming cell, mitogen-stimulated lymphocyte proliferation, splenic subset, and natural killer cell activity

    Lee, Jong Kwon; Byun, Jung A.; Park, Seung Hee; Kim, Hyung Soo; Park, Jae Hyun; Eom, Juno H.; Oh, Hye Young

    2004-01-01

    3-Monochloro-1,2-propanediol (MCPD) is a well-known by-product of acid-hydrolyzed soy sauce during its manufacturing process. MCPD has been reported genotoxic in vitro, and reproductive toxicity and carcinogenicity in rats. However, no previous studies have investigated MCPD-induced alterations in the immune system. In the present study, MCPD was administered by gavage for 14 days at 0, 25, 50, and 100 mg/kg per day to female Balb/c mice. The antibody-mediated immune response to sheep red blood cells (SRBC) was assessed using the antibody-forming cell (AFC) assay, and splenic cell phenotypes were quantified by flow cytometry. Hematological and histopathological changes were assessed. Mitogen-stimulated spleen lymphocyte proliferation and natural killer (NK) cell activity were evaluated. The T-lymphocyte blastogenesis by concanavalin A (Con A) or anti-CD3 and B-lymphocyte blastogenesis by lipopolysaccharide (LPS) were not significantly changed. There were no significant changes in the hematological and histopathological findings of MCPD-treated mice. However, the significant decrease in thymus weight was observed in 100 mg dose group, even though that did not change body weight gain. The cellularities of spleen and thymus were significantly reduced in high-dose group. Exposure to high dose of MCPD decreased the AFC response to SRBC in mice. There was a significant decrease in NK cell activity of mice treated with high dose of MCPD. These results indicate that MCPD could modulate the immune function in Balb/c mice

  11. Extract of Polygala tenuifolia Alleviates Stress-Exacerbated Atopy-Like Skin Dermatitis through the Modulation of Protein Kinase A and p38 Mitogen-Activated Protein Kinase Signaling Pathway

    Bongjun Sur

    2017-01-01

    Full Text Available Atopic dermatitis (AD and stress create a vicious cycle: stress exacerbates atopic symptoms, and atopic disease elicits stress and anxiety. Targeting multiple pathways including stress and allergic inflammation is, therefore, important for treating AD. In this study, we investigated the remedial value of Polygala tenuifolia Willd. (PTW for treating immobilization (IMO stress-exacerbated atopy-like skin dermatitis and its underlying mechanism. Trimellitic anhydride (TMA was applied to dorsal skin for sensitization and subsequently both ears for eliciting T-cell-dependent contact hypersensitivity in mice, which underwent 2 h-IMO stress and PTW administration for the latter 6 and 9 days in the ear exposure period of TMA, respectively. To elicit in vitro degranulation of human mast cell line-1 (HMC-1, 10 µM substance P (SP and 200 nM corticotrophin-releasing factor (CRF were sequentially added with 48 h-interval. PTW extract (500 µg/mL was added 30 min before CRF treatment. IMO stress exacerbated TMA-induced scratching behavior by 252%, and increased their blood corticosterone levels by two-fold. Treatment with 250 mg/kg PTW significantly restored IMO stress-exacerbated scratching behavior and other indicators such as skin inflammation and water content, lymph node weights, and serum histamine and immunoglobulin E (lgE levels. Furthermore, it also reversed TMA-stimulated expression of tumor necrosis factor (TNF-α and interleukin (IL-4 mRNAs in ear tissues. PTW significantly inhibited SP/CRF-stimulated degranulation of HMC-1 cells, subsequent tryptase secretion, and protein kinase A (PKA activity. PTW also selectively inhibited p38 mitogen-activated protein kinase (MAPK phosphorylation in SP/CRF-treated HMC-1 cells. PTW significantly inhibited HMC-1 cell degranulation and alleviated IMO stress-exacerbated atopic dermatitis symptoms by modulating the PKA/p38 MAPK signaling pathway.

  12. Andrographolide stimulates p38 mitogen-activated protein kinase-nuclear factor erythroid-2-related factor 2-heme oxygenase 1 signaling in primary cerebral endothelial cells for definite protection against ischemic stroke in rats.

    Yen, Ting-Lin; Chen, Ray-Jade; Jayakumar, Thanasekaran; Lu, Wan-Jung; Hsieh, Cheng-Ying; Hsu, Ming-Jen; Yang, Chih-Hao; Chang, Chao-Chien; Lin, Yen-Kuang; Lin, Kuan-Hung; Sheu, Joen-Rong

    2016-04-01

    Stroke pathogenesis involves complex oxidative stress-related pathways. The nuclear factor erythroid-2-related factor 2 (Nrf2) and heme oxygenase 1 (HO-1) pathways have been considered molecular targets in pharmacologic intervention for ischemic diseases. Andrographolide, a labdane diterpene, has received increasing attention in recent years because of its various pharmacologic activities. We determined that andrographolide modulates the mitogen-activated protein kinase (MAPK)-Nrf2-HO-1 signaling cascade in primary cerebral endothelial cells (CECs) to provide positive protection against middle cerebral artery occlusion (MCAO)-induced ischemic stroke in rats. In the present study, andrographolide (10 μM) increased HO-1 protein and messenger RNA expressions, Nrf2 phosphorylation, and nuclear translocation in CECs, and these activities were disrupted by a p38 MAPK inhibitor, SB203580, but not by the extracellular signal-regulated kinase inhibitor PD98059 or c-Jun amino-terminal kinase inhibitor SP600125. Similar results were observed in confocal microscopy analysis. Moreover, andrographolide-induced Nrf2 and HO-1 protein expressions were significantly inhibited by Nrf2 small interfering RNA. Moreover, HO-1 knockdown attenuated the protective effect of andrographolide against oxygen-glucose deprivation-induced CEC death. Andrographolide (0.1 mg/kg) significantly suppressed free radical formation, blood-brain barrier disruption, and brain infarction in MCAO-insulted rats, and these effects were reversed by the HO-1 inhibitor zinc protoporphyrin IX. The mechanism is attributable to HO-1 activation, as directly evidenced by andrographolide-induced pronounced HO-1 expression in brain tissues, which was highly localized in the cerebral capillary. In conclusion, andrographolide increased Nrf2-HO-1 expression through p38 MAPK regulation, confirming that it provides protection against MCAO-induced brain injury. These findings provide strong evidence that andrographolide could

  13. Sustainable growth in Europe

    Andreini, P.

    1993-01-01

    The measures till now adopted did not stop environmental deterioration in Europe and the growth of economic activities in the future will make the situation more and more heavy. The European Communities (EEC) Cabinet launched a long term program for a sustainable growth in Europe, which could conciliate economic needs with environmental protection. This paper presents the first part of the program

  14. Nutrition and growth

    Forbes, G.B.

    1977-07-01

    Longitudinal growth data on children who developed obesity during childhood reveal a distinct tendency for height gain to accelerate coincident with or after the onset of excessive weight gain. The magnitude of the relative height increment is related to the degree of overweight. Overnutrition accelerates growth, just as undernutrition retards it.

  15. Growth Modulation in Achondroplasia.

    McClure, Philip K; Kilinc, Eray; Birch, John G

    2017-09-01

    Achondroplasia is the most common skeletal dysplasia with a rate of nearly 1/10,000. The development of lower extremity deformity is well documented, and various modes of correction have been reported. There are no reports on the use of growth modulation to correct angular deformity in achondroplasia. Medical Records from 1985 to 2015 were reviewed for the diagnosis of achondroplasia and growth modulation procedures. Patients who had been treated for angular deformity of the legs by growth modulation were identified. A detailed analysis of their medical record and preoperative and final lower extremity radiographs was completed. Four patients underwent growth modulation procedures, all to correct existing varus deformity of the legs. Three of the 4 patients underwent bilateral distal femoral and proximal tibial growth modulation. The remaining patient underwent tibial correction only. Two of the 4 patients had a combined proximal fibular epiphysiodesis. All limbs had some improvement of alignment; however, 1 patient went on to bilateral osteotomies. Only 1 limb corrected to a neutral axis with growth modulation alone at last follow-up, initial implantation was done before 5 years of age. Growth modulation is an effective means for deformity correction in the setting of achondroplasia. However implantation may need to be done earlier than would be typical for patients without achondroplasia. Osteotomy may still be required after growth modulation for incomplete correction.

  16. Empowering growth in Pakistan?

    K.A. Siegmann (Karin Astrid); H. Majid (Hadia)

    2014-01-01

    textabstractPakistan's Vision 2025 connects a policy commitment to greater gender equality with inclusive growth. It prioritises a "good quality of life and high living standard for all citizens across regions, gender" and to "achieve an annual average growth rate of 7 to 8 per cent that is

  17. Strategic growth options

    Kulatilaka, N.; Perotti, E.C.

    1998-01-01

    We provide a strategic rationale for growth options under uncertainty and imperfect corn-petition. In a market with strategic competition, investment confers a greater capability to take advantage of future growth opportunities. This strategic advantage leads to the capture of a greater share of the

  18. Modeling Exponential Population Growth

    McCormick, Bonnie

    2009-01-01

    The concept of population growth patterns is a key component of understanding evolution by natural selection and population dynamics in ecosystems. The National Science Education Standards (NSES) include standards related to population growth in sections on biological evolution, interdependence of organisms, and science in personal and social…

  19. Cluster growth kinetics

    Dubovik, V.M.; Gal'perin, A.G.; Rikhvitskij, V.S.; Lushnikov, A.A.

    2000-01-01

    Processes of some traffic blocking coming into existence are considered as probabilistic ones. We study analytic solutions for models for the dynamics of both cluster growth and cluster growth with fragmentation in the systems of finite number of objects. Assuming rates constancy of both coalescence and fragmentation, the models under consideration are linear on the probability functions

  20. SLOWER BUT HEALTHIER GROWTH

    LAN XINZHEN

    2010-01-01

    @@ China's economic growth has slowed,economic statistics released on July 15 show,confirming market expectations.But officials said the country's economy is still on track. The recovery has gained traction in China,which registered a double-digit growth of 11.1 percent in the first half of this year.

  1. Trade, Growth, and Poverty

    Dollar, David; Kraay, Aart

    2001-01-01

    The evidence from individual cases and from cross-country analysis supports the view that globalization leads to faster growth and poverty reduction in poor countries. To determine the effect of globalization on growth, poverty, and inequality, the authors first identify a group of developing countries that are participating more in globalization. China, India, and several other large coun...

  2. Measures of Student Growth

    Texas Education Agency, 2016

    2016-01-01

    Beginning in the 2017-2018 school year, appraisal systems in Texas, whether the state-recommended system or a locally developed system, will need to include a measure of student growth at the individual teacher level. Student growth measures how much a student progresses academically during his or her time with a particular teacher. It takes into…

  3. Aid and Growth

    Arndt, Channing; Jones, Edward Samuel; Tarp, Finn

    , are being drawn on the basis of fragile evidence. This paper first assesses the aid-growth literature with a focus on recent contributions. The aid-growth literature is then framed, for the first time, in terms of the Rubin Causal Model, applied at the macroeconomic level. Our results show that aid has......The micro-macro paradox has been revived. Despite broadly positive evaluations at the micro and meso-levels, recent literature has turned decidedly pessimistic with respect to the ability of foreign aid to foster economic growth. Policy implications, such as the complete cessation of aid to Africa...... a positive and statistically significant causal effect on growth over the long run with point estimates at levels suggested by growth theory. We conclude that aid remains an important tool for enhancing the development prospects of poor nations....

  4. Rejuveniles and Growth

    Barnett, Richard C.; Bhattacharya, Joydeep

    Rejuveniles are "people who cultivate tastes and mind-sets tradi- tionally associated with those younger than themselves." (Noxon, 2006) In this paper, we study a standard AK growth model of overlapping generations populated by rejuve- niles. For our purposes, rejuveniles are old agents who derive...... utility from "keeping up" their consumption with that of the current young. We find that such cross-generational keeping up is capable of generating interesting equilibrium growth dynamics, including growth cycles. No such growth dynamics is possible either in the baseline model, one where...... no such generational consumption externality exists, or for almost any other form of keeping up. Steady-state growth in a world with rejuveniles may be higher than that obtained in the baseline model....

  5. Aid Effectiveness on Growth

    Doucouliagos, Hristos; Paldam, Martin

    The AEL (aid effectiveness literature) is econo¬metric studies of the macroeconomic effects of development aid. It contains about 100 papers of which 68 are reduced form estimates of theeffect of aid on growth in the recipient country. The raw data show that growth is unconnected to aid......, but the AEL has put so much structure on the data that all results possible have emerged. The present meta study considers both the best-set of the 68 papers and the all-set of 543 regressions published. Both sets have a positive average aid-growth elasticity, but it is small and insignificant: The AEL has...... betweenstudies is real. In particular, the aid-growth association is stronger for Asian countries, and the aid-growth association is shown to have been weaker in the 1970s....

  6. Transgenic Wuzhishan minipigs designed to express a dominant-negative porcine growth hormone receptor display small stature and a perturbed insulin/IGF-1 pathway.

    Li, Feida; Li, Yong; Liu, Huan; Zhang, Xingju; Liu, Chuxin; Tian, Kai; Bolund, Lars; Dou, Hongwei; Yang, Wenxian; Yang, Huanming; Staunstrup, Nicklas Heine; Du, Yutao

    2015-12-01

    Growth hormone (GH) is an anabolic mitogen with widespread influence on cellular growth and differentiation as well as on glucose and lipid metabolism. GH binding to the growth hormone receptor (GHR) on hepatocytes prompts expression of insulin growth factor I (IGF-1) involved in nutritionally induced compensatory hyperplasia of pancreatic β-cell islets and insulin release. A prolonged hyperactivity of the IGF-1/insulin axis in the face of insulinotropic nutrition, on the other hand, can lead to collapse of the pancreatic islets and glucose intolerance. Individuals with Laron syndrome carry mutations in the GHR gene resulting in severe congenital IGF-1 deficiency and elevated GH serum levels leading to short stature as well as perturbed lipid and glucose metabolism. However, these individuals enjoy a reduced prevalence of acne, cancer and possibly diabetes. Minipigs have become important biomedical models for human conditions due to similarities in organ anatomy, physiology, and metabolism relative to humans. The purpose of this study was to generate transgenic Wuzhishan minipigs by handmade cloning with impaired systemic GHR activity and assess their growth profile and glucose metabolism. Transgenic minipigs featuring overexpression of a dominant-negative porcine GHR (GHR(dm)) presented postnatal growth retardation and proportionate dwarfism. Molecular changes included elevated GH serum levels and mild hyperglycemia. We believe that this model may prove valuable in the study of GH functions in relation to cancer, diabetes and longevity.

  7. The regulation of reproductive neuroendocrine function by insulin and insulin-like growth factor-1 (IGF-1).

    Wolfe, Andrew; Divall, Sara; Wu, Sheng

    2014-10-01

    The mammalian reproductive hormone axis regulates gonadal steroid hormone levels and gonadal function essential for reproduction. The neuroendocrine control of the axis integrates signals from a wide array of inputs. The regulatory pathways important for mediating these inputs have been the subject of numerous studies. One class of proteins that have been shown to mediate metabolic and growth signals to the CNS includes Insulin and IGF-1. These proteins are structurally related and can exert endocrine and growth factor like action via related receptor tyrosine kinases. The role that insulin and IGF-1 play in controlling the hypothalamus and pituitary and their role in regulating puberty and nutritional control of reproduction has been studied extensively. This review summarizes the in vitro and in vivo models that have been used to study these neuroendocrine structures and the influence of these growth factors on neuroendocrine control of reproduction. Copyright © 2014 Elsevier Inc. All rights reserved.

  8. Mitogen-activated protein kinases mediate Mycobacterium

    CD44, an adhesion molecule, has been reported to be a binding site for Mycobacterium tuberculosis (M. tuberculosis) in macrophages and it also mediates mycobacterial phagocytosis, macrophage recruitment and protective immunity against pulmonary tuberculosis in vivo. However, the signalling pathways that are ...

  9. Mitogen-activated protein kinases mediate Mycobacterium ...

    2012-01-19

    Jan 19, 2012 ... effector molecules and also in the control of intracellular bacterial replication ..... H37Ra in THP-1 cells. The fall and rise in the activation of .... use this distinct role of p38 MAPK to balance the expression of CD44 during ...

  10. Sphingosine kinase/sphingosine 1-phosphate axis: a new player for insulin-like growth factor-1-induced myoblast differentiation

    Bernacchioni Caterina

    2012-07-01

    Full Text Available Abstract Background Insulin-like growth factor-1 (IGF-1 is the most important physiological regulator of skeletal muscle progenitor cells, which are responsible for adult skeletal muscle regeneration. The ability of IGF-1 to affect multiple aspects of skeletal muscle cell biology such as proliferation, differentiation, survival and motility is well recognized, although the molecular mechanisms implicated in its complex biological action are not fully defined. Since sphingosine 1-phosphate (S1P has recently emerged as a key player in skeletal muscle regeneration, we investigated the possible involvement of the sphingosine kinase (SK/S1P receptor axis on the biological effects of IGF-1 in murine myoblasts. Methods RNA interference, chemical inhibition and immunofluorescence approaches were used to assess the role of the SK/S1P axis on the myogenic and mitogenic effects of IGF-1 in C2C12 myoblasts. Results We show that IGF-1 increases SK activity in mouse myoblasts. The effect of the growth factor does not involve transcriptional regulation of SK1 or SK2, since the protein content of both isoforms is not affected; rather, IGF-1 enhances the fraction of the active form of SK. Moreover, transactivation of the S1P2 receptor induced by IGF-1 via SK activation appears to be involved in the myogenic effect of the growth factor. Indeed, the pro-differentiating effect of IGF-1 in myoblasts is impaired when SK activity is pharmacologically inhibited, or SK1 or SK2 are specifically silenced, or the S1P2 receptor is downregulated. Furthermore, in this study we show that IGF-1 transactivates S1P1/S1P3 receptors via SK activation and that this molecular event negatively regulates the mitogenic effect elicited by the growth factor, since the specific silencing of S1P1 or S1P3 receptors increases cell proliferation induced by IGF-1. Conclusions We demonstrate a dual role of the SK/S1P axis in response to myoblast challenge with IGF-1, that likely is important to

  11. Mesenchymal stem cell like (MSCl) cells generated from human embryonic stem cells support pluripotent cell growth

    Varga, Nora [Membrane Research Group of the Hungarian Academy of Sciences, Semmelweis University, Budapest (Hungary); Vereb, Zoltan; Rajnavoelgyi, Eva [Department of Immunology, Medical and Health Science Centre, University of Debrecen, Debrecen (Hungary); Nemet, Katalin; Uher, Ferenc; Sarkadi, Balazs [Membrane Research Group of the Hungarian Academy of Sciences, Semmelweis University, Budapest (Hungary); Apati, Agota, E-mail: apati@kkk.org.hu [Membrane Research Group of the Hungarian Academy of Sciences, Semmelweis University, Budapest (Hungary)

    2011-10-28

    Highlights: Black-Right-Pointing-Pointer MSC like cells were derived from hESC by a simple and reproducible method. Black-Right-Pointing-Pointer Differentiation and immunosuppressive features of MSCl cells were similar to bmMSC. Black-Right-Pointing-Pointer MSCl cells as feeder cells support the undifferentiated growth of hESC. -- Abstract: Mesenchymal stem cell like (MSCl) cells were generated from human embryonic stem cells (hESC) through embryoid body formation, and isolated by adherence to plastic surface. MSCl cell lines could be propagated without changes in morphological or functional characteristics for more than 15 passages. These cells, as well as their fluorescent protein expressing stable derivatives, efficiently supported the growth of undifferentiated human embryonic stem cells as feeder cells. The MSCl cells did not express the embryonic (Oct4, Nanog, ABCG2, PODXL, or SSEA4), or hematopoietic (CD34, CD45, CD14, CD133, HLA-DR) stem cell markers, while were positive for the characteristic cell surface markers of MSCs (CD44, CD73, CD90, CD105). MSCl cells could be differentiated toward osteogenic, chondrogenic or adipogenic directions and exhibited significant inhibition of mitogen-activated lymphocyte proliferation, and thus presented immunosuppressive features. We suggest that cultured MSCl cells can properly model human MSCs and be applied as efficient feeders in hESC cultures.

  12. Physiological epidermal growth factor concentrations activate high affinity receptors to elicit calcium oscillations.

    Béatrice Marquèze-Pouey

    Full Text Available Signaling mediated by the epidermal growth factor (EGF is crucial in tissue development, homeostasis and tumorigenesis. EGF is mitogenic at picomolar concentrations and is known to bind its receptor on high affinity binding sites depending of the oligomerization state of the receptor (monomer or dimer. In spite of these observations, the cellular response induced by EGF has been mainly characterized for nanomolar concentrations of the growth factor, and a clear definition of the cellular response to circulating (picomolar concentrations is still lacking. We investigated Ca2+ signaling, an early event in EGF responses, in response to picomolar doses in COS-7 cells where the monomer/dimer equilibrium is unaltered by the synthesis of exogenous EGFR. Using the fluo5F Ca2+ indicator, we found that picomolar concentrations of EGF induced in 50% of the cells a robust oscillatory Ca2+ signal quantitatively similar to the Ca2+ signal induced by nanomolar concentrations. However, responses to nanomolar and picomolar concentrations differed in their underlying mechanisms as the picomolar EGF response involved essentially plasma membrane Ca2+ channels that are not activated by internal Ca2+ store depletion, while the nanomolar EGF response involved internal Ca2+ release. Moreover, while the picomolar EGF response was modulated by charybdotoxin-sensitive K+ channels, the nanomolar response was insensitive to the blockade of these ion channels.

  13. Physiological epidermal growth factor concentrations activate high affinity receptors to elicit calcium oscillations.

    Marquèze-Pouey, Béatrice; Mailfert, Sébastien; Rouger, Vincent; Goaillard, Jean-Marc; Marguet, Didier

    2014-01-01

    Signaling mediated by the epidermal growth factor (EGF) is crucial in tissue development, homeostasis and tumorigenesis. EGF is mitogenic at picomolar concentrations and is known to bind its receptor on high affinity binding sites depending of the oligomerization state of the receptor (monomer or dimer). In spite of these observations, the cellular response induced by EGF has been mainly characterized for nanomolar concentrations of the growth factor, and a clear definition of the cellular response to circulating (picomolar) concentrations is still lacking. We investigated Ca2+ signaling, an early event in EGF responses, in response to picomolar doses in COS-7 cells where the monomer/dimer equilibrium is unaltered by the synthesis of exogenous EGFR. Using the fluo5F Ca2+ indicator, we found that picomolar concentrations of EGF induced in 50% of the cells a robust oscillatory Ca2+ signal quantitatively similar to the Ca2+ signal induced by nanomolar concentrations. However, responses to nanomolar and picomolar concentrations differed in their underlying mechanisms as the picomolar EGF response involved essentially plasma membrane Ca2+ channels that are not activated by internal Ca2+ store depletion, while the nanomolar EGF response involved internal Ca2+ release. Moreover, while the picomolar EGF response was modulated by charybdotoxin-sensitive K+ channels, the nanomolar response was insensitive to the blockade of these ion channels.

  14. Mesenchymal stem cell like (MSCl) cells generated from human embryonic stem cells support pluripotent cell growth

    Varga, Nóra; Veréb, Zoltán; Rajnavölgyi, Éva; Német, Katalin; Uher, Ferenc; Sarkadi, Balázs; Apáti, Ágota

    2011-01-01

    Highlights: ► MSC like cells were derived from hESC by a simple and reproducible method. ► Differentiation and immunosuppressive features of MSCl cells were similar to bmMSC. ► MSCl cells as feeder cells support the undifferentiated growth of hESC. -- Abstract: Mesenchymal stem cell like (MSCl) cells were generated from human embryonic stem cells (hESC) through embryoid body formation, and isolated by adherence to plastic surface. MSCl cell lines could be propagated without changes in morphological or functional characteristics for more than 15 passages. These cells, as well as their fluorescent protein expressing stable derivatives, efficiently supported the growth of undifferentiated human embryonic stem cells as feeder cells. The MSCl cells did not express the embryonic (Oct4, Nanog, ABCG2, PODXL, or SSEA4), or hematopoietic (CD34, CD45, CD14, CD133, HLA-DR) stem cell markers, while were positive for the characteristic cell surface markers of MSCs (CD44, CD73, CD90, CD105). MSCl cells could be differentiated toward osteogenic, chondrogenic or adipogenic directions and exhibited significant inhibition of mitogen-activated lymphocyte proliferation, and thus presented immunosuppressive features. We suggest that cultured MSCl cells can properly model human MSCs and be applied as efficient feeders in hESC cultures.

  15. Diabetic Foot Ulcers and Epidermal Growth Factor: Revisiting the Local Delivery Route for a Successful Outcome

    Jorge Berlanga-Acosta

    2017-01-01

    Full Text Available Soon after epidermal growth factor (EGF discovery, some in vivo models appeared demonstrating its property to enhance cutaneous wound healing. EGF was the first growth factor (GF introduced in the clinical arena as a healing enhancer, exerting its mitogenic effects on epithelial, fibroblastoid, and endothelial cells via a tyrosine kinase membrane receptor. Compelling evidences from the 90s documented that, for EGF, locally prolonged bioavailability and hourly interaction with the receptor were necessary for a successful tissue response. Eventually, the enthusiasm on the clinical use of EGF to steer the healing process was wiped out as the topical route to deliver proteins started to be questioned. The simultaneous in vivo experiments, emphasizing the impact of the parenterally administered EGF on epithelial and nonepithelial organs in terms of mitogenesis and cytoprotection, rendered the theoretical fundamentals for the injectable use of EGF and shaped the hypothesis that locally infiltrating the diabetic ulcers would lead to an effective healing. Although the diabetic chronic wounds microenvironment is hostile for local GFs bioavailability, EGF local infiltration circumvented the limitations of its topical application, thus expanding its therapeutic prospect. Our clinical pharmacovigilance and basic studies attest the significance of the GF local infiltration for chronic wounds healing.

  16. Aid and Growth

    Tarp, Finn; Mekasha, Tseday Jemaneh

    2013-01-01

    Recent litterature in the meta-analysis category where results from a range of studies are brought together throws doubt on the ability of foreign aid to foster economic growth and development. This article assesses what meta-analysis has to contribute to the litterature on the effectiveness...... of foreign aid in terms of growth impact. We re-examine key hypotheses, and find that the effect of aid on growth is positive and statistically significant. This significant effect is genuine, and not an artefact of publication selection. We also show why our results differ from those published elsewhere....

  17. Aid and Growth

    Mekasha, Tseday Jemaneh; Tarp, Finn

    Some recent literature in the meta-analysis category where results from a range of studies are brought together throws doubt on the ability of foreign aid to foster economic growth and development. This paper assesses what meta-analysis has to say about the effectiveness of foreign aid in terms...... of the growth impact. We re-examine key hypotheses, and find that the effect of aid on growth is positive and statistically significant. This significant effect is genuine, and not an artefact of publication selection. We also show why our results differ from those published elsewhere....

  18. Environment and Growth

    Horii, Ryo; Ikefuji, Masako

    . In a less developed country, this link, which we call “limits to growth,” emerges as the “poverty-environment trap,” which explains the persistent international inequality both in terms of income and environment. This link also threatens the sustainability of the world’s economic growth, particularly when...... the emission of greenhouse gases raises the risk of natural disasters. Stronger environmental policies are required to overcome this link. While there is a trade-off between the environment and growth in the short run, we show that an appropriate policy can improve both in the long run....

  19. Normal and abnormal growth plate

    Kumar, R.; Madewell, J.E.; Swischuk, L.E.

    1987-01-01

    Skeletal growth is a dynamic process. A knowledge of the structure and function of the normal growth plate is essential in order to understand the pathophysiology of abnormal skeletal growth in various diseases. In this well-illustrated article, the authors provide a radiographic classification of abnormal growth plates and discuss mechanisms that lead to growth plate abnormalities

  20. Growth assessment in diagnosis of Fetal Growth Restriction. Review.

    Albu, A R; Horhoianu, I A; Dumitrascu, M C; Horhoianu, V

    2014-06-15

    The assessment of fetal growth represents a fundamental step towards the identification of the true growth restricted fetus that is associated to important perinatal morbidity and mortality. The possible ways of detecting abnormal fetal growth are taken into consideration in this review and their strong and weak points are discussed. An important debate still remains about how to discriminate between the physiologically small fetus that does not require special surveillance and the truly growth restricted fetus who is predisposed to perinatal complications, even if its parameters are above the cut-off limits established. In this article, we present the clinical tools of fetal growth assessment: Symphyseal-Fundal Height (SFH) measurement, the fetal ultrasound parameters widely taken into consideration when discussing fetal growth: Abdominal Circumference (AC) and Estimated Fetal Weight (EFW); several types of growth charts and their characteristics: populational growth charts, standard growth charts, individualized growth charts, customized growth charts and growth trajectories.