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Sample records for increased cdk4 activity

  1. Regulation of CDK4 activity by a novel CDK4-binding protein, p34SEI-1

    PubMed Central

    Sugimoto, Masataka; Nakamura, Takeshi; Ohtani, Naoko; Hampson, Lynne; Hampson, Ian N.; Shimamoto, Akira; Furuichi, Yasuhiro; Okumura, Ko; Niwa, Shinichiro; Taya, Yoichi; Hara, Eiji

    1999-01-01

    The p16INK4a tumor suppressor inhibits cyclin-dependent kinases (CDK4 and CDK6). Here we report the isolation of a novel gene, SEI-1, whose product (p34SEI-1) appears to antagonize the function of p16INK4a. Addition of p34SEI-1 to cyclin D1–CDK4 renders the complex resistant to inhibition by p16INK4a. Expression of SEI-1 is rapidly induced on addition of serum to quiescent fibroblasts, and ectopic expression of p34SEI-1 enables fibroblasts to proliferate even in low serum concentrations. p34SEI-1 seems to act as a growth factor sensor and may facilitate the formation and activation of cyclin D–CDK complexes in the face of inhibitory levels of INK4 proteins. PMID:10580009

  2. The CDK4/CDK6 inhibitor PD0332991 paradoxically stabilizes activated cyclin D3-CDK4/6 complexes.

    PubMed

    Paternot, Sabine; Colleoni, Bianca; Bisteau, Xavier; Roger, Pierre P

    2014-01-01

    CDK4 and CDK6 bound to D-type cyclins are master integrators of G1 phase cell cycle regulations by initiating the inactivating phosphorylation of the central oncosuppressor pRb. Because of their frequent deregulation in cancer, cyclin D-CDK4/6 complexes are emerging as especially promising therapeutic targets. The specific CDK4/6 inhibitor PD0332991 is currently tested in a growing number of phase II/III clinical trials against a variety of pRb-proficient chemotherapy-resistant cancers. We have previously shown that PD0332991 inhibits not only CDK4/6 activity but also the activation by phosphorylation of the bulk of cyclin D-CDK4 complexes stabilized by p21 binding. Here we show that PD0332991 has either a positive or a negative impact on the activation of cyclin D-CDK4/6 complexes, depending on their binding to p21. Indeed, whereas PD0332991 inhibits the phosphorylation and activity of p21-bound CDK4/6, it specifically stabilized activated cyclin D3-CDK4/6 complexes devoid of p21 and p27. After elimination of PD0332991, these activated cyclin D3-CDK4/6 complexes persisted for at least 24 h, resulting in paradoxical cell cycle entry in the absence of a mitogenic stimulation. This unsuspected positive effect of PD0332991 on cyclin D3-CDK4/6 activation should be carefully assessed in the clinical evaluation of PD0332991, which until now only involves discontinuous administration protocols. PMID:25486476

  3. Inactivation of TGF-{beta} signaling in lung cancer results in increased CDK4 activity that can be rescued by ELF

    SciTech Connect

    Baek, Hye Jung; Kim, Sang Soo; Silva, Fabio May da; Volpe, Eugene A.; Evans, Stephen; Mishra, Bibhuti; Mishra, Lopa . E-mail: lopamishra@yahoo.com; Blair Marshall, M. . E-mail: mbm5@gunet.georgetown.edu

    2006-08-11

    Escape from TGF-{beta} inhibition of proliferation is a hallmark of multiple cancers including lung cancer. We explored the role of ELF, crucial TGF-{beta} adaptor protein identified from endodermal progenitor cells, in lung carcinogenesis and cell-cycle regulation. Interestingly, elf {sup -/-} mice develop multiple defects that include lung, liver, and cardiac abnormalities. Four out of 6 lung cancer and mesothelioma cell lines displayed deficiency of ELF expression with increased CDK4 expression. Immunohistochemistry and Western blot analysis of primary human lung cancers also showed decreased ELF expression and overexpression of CDK4. Moreover, rescue of ELF in ELF-deficient cell lines decreased the expression of CDK4 and resulted in accumulation of G1/S checkpoint arrested cells. These results suggest that disruption in TGF-{beta} signaling mediated by loss of ELF in lung cancer leads to cell-cycle deregulation by modulating CDK4 and ELF highlights a key role of TGF-{beta} adaptor protein in suppressing early lung cancer.

  4. Fluorescent peptide biosensor for monitoring CDK4/cyclin D kinase activity in melanoma cell extracts, mouse xenografts and skin biopsies.

    PubMed

    Prével, Camille; Pellerano, Morgan; González-Vera, Juan A; Henri, Pauline; Meunier, Laurent; Vollaire, Julien; Josserand, Véronique; Morris, May C

    2016-11-15

    Melanoma constitutes the most aggressive form of skin cancer, which further metastasizes into a deadly form of cancer. The p16(INK4a)-Cyclin D-CDK4/6-pRb pathway is dysregulated in 90% of melanomas. CDK4/Cyclin D kinase hyperactivation, associated with mutation of CDK4, amplification of Cyclin D or loss of p16(INK4a) leads to increased risk of developing melanoma. This kinase therefore constitutes a key biomarker in melanoma and an emerging pharmacological target, however there are no tools enabling direct detection or quantification of its activity. Here we report on the design and application of a fluorescent peptide biosensor to quantify CDK4 activity in melanoma cell extracts, skin biopsies and melanoma xenografts. This biosensor provides sensitive means of comparing CDK4 activity between different melanoma cell lines and further responds to CDK4 downregulation by siRNA or small-molecule inhibitors. By affording means of monitoring CDK4 hyperactivity consequent to cancer-associated molecular alterations in upstream signaling pathways that converge upon this kinase, this biosensor offers an alternative to immunological identification of melanoma-specific biomarkers, thereby constituting an attractive tool for diagnostic purposes, providing complementary functional information to histological analysis, of particular utility for detection of melanoma onset in precancerous lesions. This is indeed the first fluorescent peptide biosensor which has been successfully implemented to monitor kinase activity in skin samples and melanoma tumour xenografts. Moreover by enabling to monitor response to CDK4 inhibitors, this biosensor constitutes an attractive companion assay to identify compounds of therapeutic relevance for melanoma. PMID:27203461

  5. CDK4-mediated MnSOD activation and mitochondrial homeostasis in radioadaptive protection.

    PubMed

    Jin, Cuihong; Qin, Lili; Shi, Yan; Candas, Demet; Fan, Ming; Lu, Chung-Ling; Vaughan, Andrew T M; Shen, Rulong; Wu, Larry S; Liu, Rui; Li, Robert F; Murley, Jeffrey S; Woloschak, Gayle; Grdina, David J; Li, Jian Jian

    2015-04-01

    Mammalian cells are able to sense environmental oxidative and genotoxic conditions such as the environmental low-dose ionizing radiation (LDIR) present naturally on the earth's surface. The stressed cells then can induce a so-called radioadaptive response with an enhanced cellular homeostasis and repair capacity against subsequent similar genotoxic conditions such as a high dose radiation. Manganese superoxide dismutase (MnSOD), a primary mitochondrial antioxidant in mammals, has long been known to play a crucial role in radioadaptive protection by detoxifying O2(•-) generated by mitochondrial oxidative phosphorylation. In contrast to the well-studied mechanisms of SOD2 gene regulation, the mechanisms underlying posttranslational regulation of MnSOD for radioprotection remain to be defined. Herein, we demonstrate that cyclin D1/cyclin-dependent kinase 4 (CDK4) serves as the messenger to deliver the stress signal to mitochondria to boost mitochondrial homeostasis in human skin keratinocytes under LDIR-adaptive radioprotection. Cyclin D1/CDK4 relocates to mitochondria at the same time as MnSOD enzymatic activation peaks without significant changes in total MnSOD protein level. The mitochondrial-localized CDK4 directly phosphorylates MnSOD at serine-106 (S106), causing enhanced MnSOD enzymatic activity and mitochondrial respiration. Expression of mitochondria-targeted dominant negative CDK4 or the MnSOD-S106 mutant reverses LDIR-induced mitochondrial enhancement and adaptive protection. The CDK4-mediated MnSOD activation and mitochondrial metabolism boost are also detected in skin tissues of mice receiving in vivo whole-body LDIR. These results demonstrate a unique CDK4-mediated mitochondrial communication that allows cells to sense environmental genotoxic stress and boost mitochondrial homeostasis by enhancing phosphorylation and activation of MnSOD. PMID:25578653

  6. Cyclin D1 is dispensable for G1 control in retinoblastoma gene-deficient cells independently of cdk4 activity.

    PubMed Central

    Lukas, J; Bartkova, J; Rohde, M; Strauss, M; Bartek, J

    1995-01-01

    To elucidate the regulator-versus-target relationship in the cyclin D1/cdk4/retinoblastoma protein (pRB) pathway, we examined fibroblasts from RB-1 gene-deficient and RB-1 wild-type littermate mouse embryos (ME) and in human tumor cell lines that differed in the status of the RB-1 gene. The RB+/+ and RB-/- ME fibroblasts expressed similar protein levels of D-type cyclins, cdk4, and cdk6, showed analogous spectra and abundance of cellular proteins complexed with cdk4 and/or cyclins D1 and D2, and exhibited comparable associated kinase activities. Of the two human cell lines established from the same sarcoma biopsy, the RB-positive SKUT1B cells contained cdk4 that was mainly associated with D-type cyclins, contrary to a predominant cdk4-p16INK4 complex in the RB-deficient SKUT1A cells. Antibody-mediated neutralization of cyclin D1 arrested the RB-positive ME and SKUT1B cells in G1, whereas this cyclin appeared dispensable in the RB-deficient ME and SKUT1A cells. Lack of requirement for cyclin D1 therefore correlated with absence of functional pRB, regardless of whether active cyclin D1/cdk4 holoenzyme was present in the cells under study. Consistent with a potential role of cyclin D/cdk4 in phosphorylation of pRB, monoclonal anti-cyclin D1 antibodies supporting the associated kinase activity failed to significantly affect proliferation of RB-positive cells, whereas the antibody DCS-6, unable to coprecipitate cdk4, efficiently inhibited G1 progression and prevented pRB phosphorylation in vivo. These data provide evidence for an upstream control function of cyclin D1/cdk4, and a downstream role for pRB, in the order of events regulating transition through late G1 phase of the mammalian cell division cycle. PMID:7739541

  7. Brain Exposure of Two Selective Dual CDK4 and CDK6 Inhibitors and the Antitumor Activity of CDK4 and CDK6 Inhibition in Combination with Temozolomide in an Intracranial Glioblastoma Xenograft.

    PubMed

    Raub, Thomas J; Wishart, Graham N; Kulanthaivel, Palaniappan; Staton, Brian A; Ajamie, Rose T; Sawada, Geri A; Gelbert, Lawrence M; Shannon, Harlan E; Sanchez-Martinez, Concepcion; De Dios, Alfonso

    2015-09-01

    Effective treatments for primary brain tumors and brain metastases represent a major unmet medical need. Targeting the CDK4/CDK6-cyclin D1-Rb-p16/ink4a pathway using a potent CDK4 and CDK6 kinase inhibitor has potential for treating primary central nervous system tumors such as glioblastoma and some peripheral tumors with high incidence of brain metastases. We compared central nervous system exposures of two orally bioavailable CDK4 and CDK6 inhibitors: abemaciclib, which is currently in advanced clinical development, and palbociclib (IBRANCE; Pfizer), which was recently approved by the U.S. Food and Drug Administration. Abemaciclib antitumor activity was assessed in subcutaneous and orthotopic glioma models alone and in combination with standard of care temozolomide (TMZ). Both inhibitors were substrates for xenobiotic efflux transporters P-glycoprotein and breast cancer resistant protein expressed at the blood-brain barrier. Brain Kp,uu values were less than 0.2 after an equimolar intravenous dose indicative of active efflux but were approximately 10-fold greater for abemaciclib than palbociclib. Kp,uu increased 2.8- and 21-fold, respectively, when similarly dosed in P-gp-deficient mice. Abemaciclib had brain area under the curve (0-24 hours) Kp,uu values of 0.03 in mice and 0.11 in rats after a 30 mg/kg p.o. dose. Orally dosed abemaciclib significantly increased survival in a rat orthotopic U87MG xenograft model compared with vehicle-treated animals, and efficacy coincided with a dose-dependent increase in unbound plasma and brain exposures in excess of the CDK4 and CDK6 Ki values. Abemaciclib increased survival time of intracranial U87MG tumor-bearing rats similar to TMZ, and the combination of abemaciclib and TMZ was additive or greater than additive. These data show that abemaciclib crosses the blood-brain barrier and confirm that both CDK4 and CDK6 inhibitors reach unbound brain levels in rodents that are expected to produce enzyme inhibition; however

  8. Overexpression of cyclin D1-CDK4 in silica-induced transformed cells is due to activation of ERKs, JNKs/AP-1 pathway.

    PubMed

    Shen, Fuhai; Fan, Xueyun; Liu, Bingci; Jia, Xiaowei; Du, Hongju; You, Baorong; Ye, Meng; Huang, Chuanshu; Shi, Xianglin

    2006-01-25

    Silica has been known to be a factor inducing acute injury and chronic pulmonary fibrosis. Silica has also been listed as a human carcinogen in 1996 by International Agency for Research on Cancer (IARC). However, the molecular mechanisms involved its pathologic effects are not well understood. In these studies, we found that exposure of human embryonic lung fibroblasts (HELF) to crystalline silica could cause increases in activation of extracellular signal-regulated kinases (ERKs), p38K, and c-Jun NH2-terminal amino kinases (JNKs), and HELF transformation. Interestingly, silica-induced transformation of HELF (S-HELF) led to increases in activated levels of ERKs and p46 of JNKs, and decrease in p38K activation, and no effect on activation of p54 of JNKs, as compared with those in parental HELF. Further studies showed that there are differential effects of ERKs, JNKs and p38K, as well as their downstream transcription factor AP-1, in regulation of expression of cyclin D1 and CDK4 and cell cycle alternations induced by silica. Cyclin D1 and CDK4 were increased in S-HELF as compared with those in HELF. Inhibition of ERKs activation by AG126, JNK by SP600125, and AP-1 by curcumin could reduced the induction of cyclin D1 and CDK4. There is no significant difference for cell cycle distribution between groups. These results demonstrate that ERKs and JNKs, but not p38K is responsible for induction of cyclin D1 and CDK4 in S-HELF, suggesting that overexpression of cyclin D1 and CDK4 caused by silica is mediated by ERK, JNK/AP-1signaling pathway. PMID:16125882

  9. cAMP-dependent activation of mammalian target of rapamycin (mTOR) in thyroid cells. Implication in mitogenesis and activation of CDK4.

    PubMed

    Blancquaert, Sara; Wang, Lifu; Paternot, Sabine; Coulonval, Katia; Dumont, Jacques E; Harris, Thurl E; Roger, Pierre P

    2010-07-01

    How cAMP-dependent protein kinases [protein kinase A (PKA)] transduce the mitogenic stimulus elicited by TSH in thyroid cells to late activation of cyclin D3-cyclin-dependent kinase 4 (CDK4) remains enigmatic. Here we show in PC Cl3 rat thyroid cells that TSH/cAMP, like insulin, activates the mammalian target of rapamycin (mTOR)-raptor complex (mTORC1) leading to phosphorylation of S6K1 and 4E-BP1. mTORC1-dependent S6K1 phosphorylation in response to both insulin and cAMP required amino acids, whereas inhibition of AMP-activated protein kinase and glycogen synthase kinase 3 enhanced insulin but not cAMP effects. Unlike insulin, TSH/cAMP did not activate protein kinase B or induce tuberous sclerosis complex 2 phosphorylation at T1462 and Y1571. However, like insulin, TSH/cAMP produced a stable increase in mTORC1 kinase activity that was associated with augmented 4E-BP1 binding to raptor. This could be caused in part by T246 phosphorylation of PRAS40, which was found as an in vitro substrate of PKA. Both in PC Cl3 cells and primary dog thyrocytes, rapamycin inhibited DNA synthesis and retinoblastoma protein phosphorylation induced by TSH and insulin. Although rapamycin reduced cyclin D3 accumulation, the abundance of cyclin D3-CDK4 complexes was not affected. However, rapamycin inhibited the activity of these complexes by decreasing the TSH and insulin-mediated stimulation of activating T172 phosphorylation of CDK4. We propose that mTORC1 activation by TSH, at least in part through PKA-dependent phosphorylation of PRAS40, crucially contributes to mediate cAMP-dependent mitogenesis by regulating CDK4 T172-phosphorylation. PMID:20484410

  10. CDK4 is an essential insulin effector in adipocytes

    PubMed Central

    Lagarrigue, Sylviane; Lopez-Mejia, Isabel C.; Denechaud, Pierre-Damien; Escoté, Xavier; Castillo-Armengol, Judit; Jimenez, Veronica; Chavey, Carine; Giralt, Albert; Lai, Qiuwen; Zhang, Lianjun; Martinez-Carreres, Laia; Delacuisine, Brigitte; Annicotte, Jean-Sébastien; Blanchet, Emilie; Huré, Sébastien; Abella, Anna; Tinahones, Francisco J.; Vendrell, Joan; Dubus, Pierre; Bosch, Fatima; Kahn, C. Ronald; Fajas, Lluis

    2015-01-01

    Insulin resistance is a fundamental pathogenic factor that characterizes various metabolic disorders, including obesity and type 2 diabetes. Adipose tissue contributes to the development of obesity-related insulin resistance through increased release of fatty acids, altered adipokine secretion, and/or macrophage infiltration and cytokine release. Here, we aimed to analyze the participation of the cyclin-dependent kinase 4 (CDK4) in adipose tissue biology. We determined that white adipose tissue (WAT) from CDK4-deficient mice exhibits impaired lipogenesis and increased lipolysis. Conversely, lipolysis was decreased and lipogenesis was increased in mice expressing a mutant hyperactive form of CDK4 (CDK4R24C). A global kinome analysis of CDK4-deficient mice following insulin stimulation revealed that insulin signaling is impaired in these animals. We determined that insulin activates the CCND3-CDK4 complex, which in turn phosphorylates insulin receptor substrate 2 (IRS2) at serine 388, thereby creating a positive feedback loop that maintains adipocyte insulin signaling. Furthermore, we found that CCND3 expression and IRS2 serine 388 phosphorylation are increased in human obese subjects. Together, our results demonstrate that CDK4 is a major regulator of insulin signaling in WAT. PMID:26657864

  11. Targeting CDK4/6 in patients with cancer.

    PubMed

    Hamilton, Erika; Infante, Jeffrey R

    2016-04-01

    The cyclin D-cyclin dependent kinase (CDK) 4/6-inhibitor of CDK4 (INK4)-retinoblastoma (Rb) pathway controls cell cycle progression by regulating the G1-S checkpoint. Dysregulation of the cyclin D-CDK4/6-INK4-Rb pathway results in increased proliferation, and is frequently observed in many types of cancer. Pathway activation can occur through a variety of mechanisms, including gene amplification or rearrangement, loss of negative regulators, epigenetic alterations, and point mutations in key pathway components. Due to the importance of CDK4/6 activity in cancer cells, CDK4/6 inhibitors have emerged as promising candidates for cancer treatment. Moreover, combination of a CDK4/6 inhibitor with other targeted therapies may help overcome acquired or de novo treatment resistance. Ongoing studies include combinations of CDK4/6 inhibitors with endocrine therapy and phosphatidylinositol 3-kinase (PI3K) pathway inhibitors for hormone receptor-positive (HR+) breast cancers, and with selective RAF and MEK inhibitors for tumors with alterations in the mitogen activated protein kinase (MAPK) pathway such as melanoma. In particular, the combination of CDK4/6 inhibitors with endocrine therapy, such as palbociclib's recent first-line approval in combination with letrozole, is expected to transform the treatment of HR+ breast cancer. Currently, three selective CDK4/6 inhibitors have been approved or are in late-stage development: palbociclib (PD-0332991), ribociclib (LEE011), and abemaciclib (LY2835219). Here we describe the current preclinical and clinical data for these novel agents and discuss combination strategies with other agents for the treatment of cancer. PMID:27017286

  12. Efficacy of CDK4 inhibition against sarcomas depends on their levels of CDK4 and p16ink4 mRNA

    PubMed Central

    Perez, Marco; Muñoz-Galván, Sandra; Jiménez-García, Manuel P.; Marín, Juan J.; Carnero, Amancio

    2015-01-01

    Sarcomas are malignant tumors accounting for a high percentage of cancer morbidity and mortality in children and young adults. Surgery and radiation therapy are the accepted treatments for most sarcomas; however, patients with metastatic disease are treated with systemic chemotherapy. Many tumors display marginal levels of chemoresponsiveness and new treatment approaches are needed. Deregulation of the G1 checkpoint is crucial for various oncogenic transformation processes, suggesting that many cancer cell types depend on CDK4/6 activity. Thus, CDK4/6 activity appears to represent a promising therapeutic target for cancer treatment. In the present work, we explore the efficacy of CDK4 inhibition using palbociclib (PD0332991), a highly selective inhibitor of CDK4/6, in a panel of sarcoma cell lines and sarcoma tumor xenografts (PDXs). Palbociclib induces senescence in these cell lines and the responsiveness of these cell lines correlated with their levels of CDK4 mRNA. Palbociclib is also active in vivo against sarcomas displaying high levels of CDK4 but not against sarcomas displaying low levels of CDK4 and high levels of p16ink4a. The analysis of tumors growing after palbociclib showed a clear decrease in the CDK4 levels, indicating that clonal selection occurred in these treated tumors. In summary, our data support the efficacy of CDK4 inhibitors against sarcomas displaying increased CDK4 levels, particularly fibrosarcomas and MPNST. Our results also suggest that high levels of p16ink4a may indicate poor efficacy of CDK4 inhibitors. PMID:26528855

  13. Loss of Keratinocytic RXRα Combined with Activated CDK4 or oncogenic NRAS Generates UVB-induced Melanomas via Loss of p53 and PTEN in the Tumor Microenvironment

    PubMed Central

    Coleman, Daniel J.; Chagani, Sharmeen; Hyter, Stephen; Sherman, Anna M.; Löhr, Christiane V.; Liang, Xiaobo; Ganguli-Indra, Gitali; Indra, Arup K.

    2014-01-01

    Understanding the molecular mechanisms behind formation of melanoma, the deadliest form of skin cancer, is crucial for improved diagnosis and treatment. One key is to better understand the cross-talk between epidermal keratinocytes and pigment-producing melanocytes. Here, using a bigenic mouse model system combining mutant oncogenic NRASQ61K (constitutively active RAS) or mutant activated CDK4R24C/R24C (prevents binding of CDK4 by kinase inhibitor p16INK4A) with an epidermis-specific knockout of the nuclear retinoid X receptor alpha (RXRαep−/−) results in increased melanoma formation after chronic ultraviolet-B (UVB) irradiation compared to control mice with functional RXRα. Melanomas from both groups of bigenic RXRαep−/− mice are larger in size with higher proliferative capacity, and exhibit enhanced angiogenic properties and increased expression of malignant melanoma markers. Analysis of tumor adjacent normal skin from these mice revealed altered expression of several biomarkers indicative of enhanced melanoma susceptibility, including reduced expression of tumor suppressor p53 and loss of PTEN, with concomitant increase in activated AKT. Loss of epidermal RXRα in combination with UVB significantly enhances invasion of melanocytic cells to draining lymph nodes in bigenic mice expressing oncogenic NRASQ61K compared to controls with functional RXRα. These results suggest a crucial role of keratinocytic RXRα to suppress formation of UVB-induced melanomas and their progression to malignant cancers in the context of driver mutations such as activated CDK4R24C/R24C or oncogenic NRASQ61K. PMID:25189354

  14. Cooperativity of Cdk4R24C and Ras in melanoma development.

    PubMed

    Chawla, Rachna; Procknow, Judith A; Tantravahi, Ramana V; Khurana, Jasvir S; Litvin, Judith; Reddy, E Premkumar

    2010-08-15

    The importance of the CDK4 protein in human cancer first became evident following the identification of a germ line mutation in the Cdk4 locus that predisposes humans to melanoma. This mutation results in substitution of arginine with cysteine at position 24 (R24C). In an earlier study, we introduced the R24C mutation into the Cdk4 locus of mice using Cre-loxP-mediated "knock-in" technology and observed a very low incidence of spontaneous melanomas in Cdk4(R24C/R24C) mice. This suggested that additional oncogenic mutations might be required for development of melanomas. Here we report an increased incidence of spontaneous cutaneous melanoma in mice expressing the oncogene HRAS(G12V) in melanocytes on a Cdk4(R24C) background. Treatment of Tyr-HRas:Cdk4(R24C/R24C) mice with the carcinogen, DMBA/TPA resulted in a further increase in the number of nevi and melanomas developed when compared with Tyr-HRas:Cdk4(+/+) mice. In summary, in Tyr-HRas:Cdk4(R24C/R24C) mice, we observed that activated CDK4 cooperates with the oncogenic HRAS(G12V) protein to increase the susceptibility of melanoma development in vivo. PMID:20703083

  15. cdk4 Deficiency Inhibits Skin Tumor Development but Does Not Affect Normal Keratinocyte Proliferation

    PubMed Central

    Rodriguez-Puebla, Marcelo L.; Miliani de Marval, Paula L.; LaCava, Margaret; Moons, David S.; Kiyokawa, Hiroaki; Conti, Claudio J.

    2002-01-01

    Most human tumors have mutations that result in deregulation of the cdk4/cyclin-Ink4-Rb pathway. Overexpression of D-type cyclins or cdk4 and inactivation of Ink4 inhibitors are common in human tumors. Conversely, lack of cyclin D1 expression results in significant reduction in mouse skin and mammary tumor development. However, complete elimination of tumor development was not observed in these models, suggesting that other cyclin/cdk complexes play an important role in tumorigenesis. Here we described the effects of cdk4 deficiency on mouse skin proliferation and tumor development. Cdk4 deficiency resulted in a 98% reduction in the number of tumors generated through the two-stage carcinogenesis model. The absence of cdk4 did not affect normal keratinocyte proliferation and both wild-type and cdk4 knockout epidermis are equally affected after topical treatment with the tumor promoter 12-O-tetradecanoylphorbol-13-acetate (TPA), resulting in epidermal hyperplasia. In similar fashion, cdk4 knockout keratinocytes proliferated well in an in vivo model of wound-induced proliferation. Biochemical studies in mouse epidermis showed that cdk6 activity increased twofold in cdk4-deficient mice compared to wild-type siblings. These results suggest that therapeutic approaches to inhibit cdk4 activity could provide a target to inhibit tumor development with minimal or no effect in normal tissue. PMID:12163365

  16. A dominant-negative cyclin D1 mutant prevents nuclear import of cyclin-dependent kinase 4 (CDK4) and its phosphorylation by CDK-activating kinase.

    PubMed Central

    Diehl, J A; Sherr, C J

    1997-01-01

    Cyclins contain two characteristic cyclin folds, each consisting of five alpha-helical bundles, which are connected to one another by a short linker peptide. The first repeat makes direct contact with cyclin-dependent kinase (CDK) subunits in assembled holoenzyme complexes, whereas the second does not contribute directly to the CDK interface. Although threonine 156 in mouse cyclin D1 is predicted to lie at the carboxyl terminus of the linker peptide that separates the two cyclin folds and is buried within the cyclin subunit, mutation of this residue to alanine has profound effects on the behavior of the derived cyclin D1-CDK4 complexes. CDK4 in complexes with mutant cyclin D1 (T156A or T156E but not T156S) is not phosphorylated by recombinant CDK-activating kinase (CAK) in vitro, fails to undergo activating T-loop phosphorylation in vivo, and remains catalytically inactive and unable to phosphorylate the retinoblastoma protein. Moreover, when it is ectopically overexpressed in mammalian cells, cyclin D1 (T156A) assembles with CDK4 in the cytoplasm but is not imported into the cell nucleus. CAK phosphorylation is not required for nuclear transport of cyclin D1-CDK4 complexes, because complexes containing wild-type cyclin D1 and a CDK4 (T172A) mutant lacking the CAK phosphorylation site are efficiently imported. In contrast, enforced overexpression of the CDK inhibitor p21Cip1 together with mutant cyclin D1 (T156A)-CDK4 complexes enhanced their nuclear localization. These results suggest that cyclin D1 (T156A or T156E) forms abortive complexes with CDK4 that prevent recognition by CAK and by other cellular factors that are required for their nuclear localization. These properties enable ectopically overexpressed cyclin D1 (T156A), or a more stable T156A/T286A double mutant that is resistant to ubiquitination, to compete with endogenous cyclin D1 in mammalian cells, thereby mobilizing CDK4 into cytoplasmic, catalytically inactive complexes and dominantly inhibiting

  17. c-Myc Regulates Cyclin D-Cdk4 and -Cdk6 Activity but Affects Cell Cycle Progression at Multiple Independent Points

    PubMed Central

    Mateyak, Maria K.; Obaya, Alvaro J.; Sedivy, John M.

    1999-01-01

    c-myc is a cellular proto-oncogene associated with a variety of human cancers and is strongly implicated in the control of cellular proliferation, programmed cell death, and differentiation. We have previously reported the first isolation of a c-myc-null cell line. Loss of c-Myc causes a profound growth defect manifested by the lengthening of both the G1 and G2 phases of the cell cycle. To gain a clearer understanding of the role of c-Myc in cellular proliferation, we have performed a comprehensive analysis of the components that regulate cell cycle progression. The largest defect observed in c-myc−/− cells is a 12-fold reduction in the activity of cyclin D1-Cdk4 and -Cdk6 complexes during the G0-to-S transition. Downstream events, such as activation of cyclin E-Cdk2 and cyclin A-Cdk2 complexes, are delayed and reduced in magnitude. However, it is clear that c-Myc affects the cell cycle at multiple independent points, because restoration of the Cdk4 and -6 defect does not significantly increase growth rate. In exponentially cycling cells the absence of c-Myc reduces coordinately the activities of all cyclin–cyclin-dependent kinase complexes. An analysis of cyclin-dependent kinase complex regulators revealed increased expression of p27KIP1 and decreased expression of Cdk7 in c-myc−/− cells. We propose that c-Myc functions as a crucial link in the coordinate adjustment of growth rate to environmental conditions. PMID:10373516

  18. Metabolic Reprogramming of Pancreatic Cancer Mediated by CDK4/6 Inhibition Elicits Unique Vulnerabilities.

    PubMed

    Franco, Jorge; Balaji, Uthra; Freinkman, Elizaveta; Witkiewicz, Agnieszka K; Knudsen, Erik S

    2016-02-01

    Due to loss of p16ink4a in pancreatic ductal adenocarcinoma (PDA), pharmacological suppression of CDK4/6 could represent a potent target for treatment. In PDA models, CDK4/6 inhibition had a variable effect on cell cycle but yielded accumulation of ATP and mitochondria. Pharmacological CDK4/6 inhibitors induce cyclin D1 protein levels; however, RB activation was required and sufficient for mitochondrial accumulation. CDK4/6 inhibition stimulated glycolytic and oxidative metabolism and was associated with an increase in mTORC1 activity. MTOR and MEK inhibitors potently cooperate with CDK4/6 inhibition in eliciting cell-cycle exit. However, MTOR inhibition fully suppressed metabolism and yielded apoptosis and suppression of tumor growth in xenograft models. The metabolic state mediated by CDK4/6 inhibition increases mitochondrial number and reactive oxygen species (ROS). Concordantly, the suppression of ROS scavenging or BCL2 antagonists cooperated with CDK4/6 inhibition. Together, these data define the impact of therapeutics on PDA metabolism and provide strategies for converting cytostatic response to tumor cell killing. PMID:26804906

  19. Cyclin D1 stimulation of estrogen receptor transcriptional activity independent of cdk4.

    PubMed Central

    Neuman, E; Ladha, M H; Lin, N; Upton, T M; Miller, S J; DiRenzo, J; Pestell, R G; Hinds, P W; Dowdy, S F; Brown, M; Ewen, M E

    1997-01-01

    Cyclin D1 plays an important role in the development of breast cancer and is required for normal breast cell proliferation and differentiation associated with pregnancy. We show that ectopic expression of cyclin D1 can stimulate the transcriptional activity of the estrogen receptor in the absence of estradiol and that this activity can be inhibited by 4-hydroxytamoxifen and ICI 182,780. Cyclin D1 can form a specific complex with the estrogen receptor. Stimulation of the estrogen receptor by cyclin D1 is independent of cyclin-dependent kinase 4 activation. Cyclin D1 may manifest its oncogenic potential in breast cancer in part through binding to the estrogen receptor and activation of the transcriptional activity of the receptor. PMID:9271411

  20. The CDK4/6 inhibitor LY2835219 has potent activity in combination with mTOR inhibitor in head and neck squamous cell carcinoma

    PubMed Central

    Koh, Jiae; Bae, Yeon-Hee; Sun, Jong-Mu; Lee, Se-hoon; Ahn, Jin Seok; Park, Keunchil; Ahn, Myung-Ju

    2016-01-01

    Deletion of CDKN2A (p16) or amplification of CCND1 (cyclin D1) occurs commonly in head and neck squamous cell carcinoma (HNSCC) and induces sustained cyclin-dependent kinase (CDK) 4/6 activation. Here, we report the antiproliferative activity of LY2835219, a selective CDK4/6 inhibitor through inhibition of CDK4/6-dependent Ser780 phosphorylation in retinoblastoma (RB) and induction of cell cycle arrest in HNSCC cells. In addition, we demonstrated the antitumor effects of HNSCC xenografts to LY2835219 in vivo. Given the limited effect in HNSCC as a single-agent treatment with LY2835219, a combinational strategy is required to enhance antitumor activity. At the molecular level, we found that LY2835219 inhibited activation of AKT and ERK, but not mTOR. The combination of LY2835219 with mTOR inhibitor was found to be more effective than either drug alone in vitro and in vivo. Taken together, our findings suggest that a combinational treatment with LY2835219 and mTOR inhibitor is a promising therapeutic approach for HNSCC. PMID:26909611

  1. Cdk2 deficiency decreases ras/CDK4-dependent malignant progression, but not myc-induced tumorigenesis.

    PubMed

    Macias, Everardo; Kim, Yongbaek; Miliani de Marval, Paula L; Klein-Szanto, Andres; Rodriguez-Puebla, Marcelo L

    2007-10-15

    We have previously shown that forced expression of CDK4 in mouse skin (K5CDK4 mice) results in increased susceptibility to squamous cell carcinoma (SCC) development in a chemical carcinogenesis protocol. This protocol induces skin papilloma development, causing a selection of cells bearing activating Ha-ras mutations. We have also shown that myc-induced epidermal proliferation and oral tumorigenesis (K5Myc mice) depends on CDK4 expression. Biochemical analysis of K5CDK4 and K5Myc epidermis as well as skin tumors showed that keratinocyte proliferation is mediated by CDK4 sequestration of p27Kip1 and p21Cip1, and activation of CDK2. Here, we studied the role of CDK2 in epithelial tumorigenesis. In normal skin, loss of CDK2 rescues CDK4-induced, but not myc-induced epidermal hyperproliferation. Ablation of CDK2 in K5CDK4 mice results in decreased incidences and multiplicity of skin tumors as well as malignant progression to SCC. Histopathologic analysis showed that K5CDK4 tumors are drastically more aggressive than K5CDK4/CDK2-/- tumors. On the other hand, we show that CDK2 is dispensable for myc-induced tumorigenesis. In contrast to our previous report of K5Myc/CDK4-/-, K5Myc/CDK2-/- mice developed oral tumors with the same frequency as K5Myc mice. Overall, we have established that ras-induced tumors are more susceptible to CDK2 ablation than myc-induced tumors, suggesting that the efficacy of targeting CDK2 in tumor development and malignant progression is dependent on the oncogenic pathway involved. PMID:17942901

  2. Evidence for a CDK4-dependent checkpoint in a conditional model of cellular senescence

    PubMed Central

    Brookes, Sharon; Gagrica, Sladjana; Sanij, Elaine; Rowe, Janice; Gregory, Fiona J; Hara, Eiji; Peters, Gordon

    2015-01-01

    Cellular senescence, the stable cell cycle arrest elicited by various forms of stress, is an important facet of tumor suppression. Although much is known about the key players in the implementation of senescence, including the pRb and p53 axes and the cyclin dependent kinase inhibitors p16INK4a and p21CIP1, many details remain unresolved. In studying conditional senescence in human fibroblasts that express a temperature sensitive SV40 large T-antigen (T-Ag), we uncovered an unexpected role for CDK4. At the permissive temperature, where pRb and p53 are functionally compromised by T-Ag, cyclin D-CDK4 complexes are disrupted by the high p16INK4a levels and reduced expression of p21CIP1. In cells arrested at the non-permissive temperature, p21CIP1 promotes reassembly of cyclin D-CDK4 yet pRb is in a hypo-phosphorylated state, consistent with cell cycle arrest. In exploring whether the reassembled cyclin D-CDK4-p21 complexes are functional, we found that shRNA-mediated knockdown or chemical inhibition of CDK4 prevented the increase in cell size associated with the senescent phenotype by allowing the cells to arrest in G1 rather than G2/M. The data point to a role for CDK4 kinase activity in a G2 checkpoint that contributes to senescence. PMID:25695870

  3. Metabolic re-programming of pancreatic cancer mediated by CDK4/6 inhibition elicits unique vulnerabilities

    PubMed Central

    Franco, Jorge; Balaji, Uthra; Freinkman, Elizaveta; Witkiewicz, Agnieszka K.; Knudsen, Erik S.

    2016-01-01

    Due to loss of p16ink4a in pancreatic ductal adenocarcinoma (PDA), pharmacological suppression of CDK4/6 could represent a potent target for treatment. In PDA models CDK4/6 inhibition had variable effect on cell cycle, but yielded accumulation of ATP and mitochondria. Pharmacological CDK4/6 inhibitors induce cyclin D1 protein levels; however, RB activation was required and sufficient for mitochondrial accumulation. CDK4/6 inhibition stimulated glycolytic and oxidative metabolism and was associated with an increase in mTORC1 activity. MTOR and MEK inhibitors potently cooperate with CDK4/6 inhibition in eliciting cell cycle exit. However, MTOR inhibition fully suppressed metabolism and yielded apoptosis and suppression of tumor growth. The metabolic state mediated by CDK4/6 inhibition increases mitochondrial number and ROS. Concordantly, the suppression of ROS scavenging or BCL2-antagonists cooperated with CDK4/6 inhibition. Together, these data define the impact of therapeutics on PDA metabolism and provide strategies for converting cytostatic response to tumor cell killing. PMID:26804906

  4. Loss of nuclear receptor RXRα in epidermal keratinocytes promotes the formation of Cdk4-activated invasive melanomas.

    PubMed

    Hyter, Stephen; Bajaj, Gaurav; Liang, Xiaobo; Barbacid, Mariano; Ganguli-Indra, Gitali; Indra, Arup Kumar

    2010-10-01

    Keratinocytes contribute to melanocyte transformation by affecting their microenvironment, in part through the secretion of paracrine factors. Here we report a loss of expression of nuclear receptor RXRα in epidermal keratinocytes during human melanoma progression. In the absence of keratinocytic RXRα, in combination with mutant Cdk4, cutaneous melanoma was generated that metastasized to lymph nodes in a bigenic mouse model. Expression of several keratinocyte-derived mitogenic growth factors (Et-1, Hgf, Scf, α-MSH and Fgf 2 ) was elevated in skin of bigenic mice, whereas Fas, E-cadherin and Pten, implicated in apoptosis, cellular invasion and melanomagenesis, respectively, were downregulated within the microdissected melanocytic tumors. We demonstrated that RXRα is recruited on the proximal promoter of both Et-1 and Hgf, possibly directly regulating their transcription in keratinocytes. These studies demonstrate the contribution of keratinocytic paracrine signaling during the cellular transformation and malignant conversion of melanocytes. PMID:20629968

  5. miR-124 downregulation leads to breast cancer progression via LncRNA-MALAT1 regulation and CDK4/E2F1 signal activation

    PubMed Central

    Feng, Tongbao; Shao, Fang; Wu, Qiyong; Zhang, Xiaohang; Xu, Dongqin; Qian, Keqing; Xie, Yewen; Wang, Shizhong; Xu, Ning; Wang, Yong; Qi, Chunjian

    2016-01-01

    The long non-coding RNA (lncRNA) metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) has been recently shown to be dysregulated in several cancers. However, the mechanisms underlying the role of MALAT1 in breast cancer remain unclear. Herein, we showed that MALAT1 was aberrantly increased in breast cancer tissues and cells. MALAT1-siRNA inhibited breast cancer cell proliferation and cell cycle progression in vitro and in vivo. Furthermore, MALAT1 acted as an endogenous potent regulator by directly binding to miR-124 and down-regulating miR-124 expression. In addition, MALAT1 reversed the inhibitory effect of miR-124 on breast cancer proliferation and was involved in the cyclin-dependent kinase 4 (CDK4) expression. Taken together, our data highlight the pivotal role of MALAT1 in breast cancer tumorigenesis. Moreover, the present study elucidated the MALAT1-miR-124-CDK4/E2F1 signaling pathway in breast cancer, which might provide a new approach for tackling breast cancer. PMID:26918449

  6. Dual Targeting of CDK4 and ARK5 Using a Novel Kinase Inhibitor ON123300 Exerts Potent Anticancer Activity against Multiple Myeloma.

    PubMed

    Perumal, Deepak; Kuo, Pei-Yu; Leshchenko, Violetta V; Jiang, Zewei; Divakar, Sai Krishna Athaluri; Cho, Hearn Jay; Chari, Ajai; Brody, Joshua; Reddy, M V Ramana; Zhang, Weijia; Reddy, E Premkumar; Jagannath, Sundar; Parekh, Samir

    2016-03-01

    Multiple myeloma is a fatal plasma cell neoplasm accounting for over 10,000 deaths in the United States each year. Despite new therapies, multiple myeloma remains incurable, and patients ultimately develop drug resistance and succumb to the disease. The response to selective CDK4/6 inhibitors has been modest in multiple myeloma, potentially because of incomplete targeting of other critical myeloma oncogenic kinases. As a substantial number of multiple myeloma cell lines and primary samples were found to express AMPK-related protein kinase 5(ARK5), a member of the AMPK family associated with tumor growth and invasion, we examined whether dual inhibition of CDK4 and ARK5 kinases using ON123300 results in a better therapeutic outcome. Treatment of multiple myeloma cell lines and primary samples with ON123300 in vitro resulted in rapid induction of cell-cycle arrest followed by apoptosis. ON123300-mediated ARK5 inhibition or ARK5-specific siRNAs resulted in the inhibition of the mTOR/S6K pathway and upregulation of the AMPK kinase cascade. AMPK upregulation resulted in increased SIRT1 levels and destabilization of steady-state MYC protein. Furthermore, ON123300 was very effective in inhibiting tumor growth in mouse xenograft assays. In addition, multiple myeloma cells sensitive to ON123300 were found to have a unique genomic signature that can guide the clinical development of ON123300. Our study provides preclinical evidence that ON123300 is unique in simultaneously inhibiting key oncogenic pathways in multiple myeloma and supports further development of ARK5 inhibition as a therapeutic approach in multiple myeloma. PMID:26873845

  7. Treating cancer with selective CDK4/6 inhibitors.

    PubMed

    O'Leary, Ben; Finn, Richard S; Turner, Nicholas C

    2016-07-01

    Uncontrolled cellular proliferation, mediated by dysregulation of the cell-cycle machinery and activation of cyclin-dependent kinases (CDKs) to promote cell-cycle progression, lies at the heart of cancer as a pathological process. Clinical implementation of first-generation, nonselective CDK inhibitors, designed to inhibit this proliferation, was originally hampered by the high risk of toxicity and lack of efficacy noted with these agents. The emergence of a new generation of selective CDK4/6 inhibitors, including ribociclib, abemaciclib and palbociclib, has enabled tumour types in which CDK4/6 has a pivotal role in the G1-to-S-phase cell-cycle transition to be targeted with improved effectiveness, and fewer adverse effects. Results of pivotal phase III trials investigating palbociclib in patients with advanced-stage oestrogen receptor (ER)-positive breast cancer have demonstrated a substantial improvement in progression-free survival, with a well-tolerated toxicity profile. Mechanisms of acquired resistance to CDK4/6 inhibitors are beginning to emerge that, although unwelcome, might enable rational post-CDK4/6 inhibitor therapeutic strategies to be identified. Extending the use of CDK4/6 inhibitors beyond ER-positive breast cancer is challenging, and will likely require biomarkers that are predictive of a response, and the use of combination therapies in order to optimize CDK4/6 targeting. PMID:27030077

  8. Preclinical characterization of the CDK4/6 inhibitor LY2835219: in-vivo cell cycle-dependent/independent anti-tumor activities alone/in combination with gemcitabine.

    PubMed

    Gelbert, Lawrence M; Cai, Shufen; Lin, Xi; Sanchez-Martinez, Concepcion; Del Prado, Miriam; Lallena, Maria Jose; Torres, Raquel; Ajamie, Rose T; Wishart, Graham N; Flack, Robert Steven; Neubauer, Blake Lee; Young, Jamie; Chan, Edward M; Iversen, Philip; Cronier, Damien; Kreklau, Emiko; de Dios, Alfonso

    2014-10-01

    The G1 restriction point is critical for regulating the cell cycle and is controlled by the Rb pathway (CDK4/6-cyclin D1-Rb-p16/ink4a). This pathway is important because of its inactivation in a majority of human tumors. Transition through the restriction point requires phosphorylation of retinoblastoma protein (Rb) by CDK4/6, which are highly validated cancer drug targets. We present the identification and characterization of a potent CDK4/6 inhibitor, LY2835219. LY2835219 inhibits CDK4 and CDK6 with low nanomolar potency, inhibits Rb phosphorylation resulting in a G1 arrest and inhibition of proliferation, and its activity is specific for Rb-proficient cells. In vivo target inhibition studies show LY2835219 is a potent inhibitor of Rb phosphorylation, induces a complete cell cycle arrest and suppresses expression of several Rb-E2F-regulated proteins 24 hours after a single dose. Oral administration of LY2835219 inhibits tumor growth in human tumor xenografts representing different histologies in tumor-bearing mice. LY2835219 is effective and well tolerated when administered up to 56 days in immunodeficient mice without significant loss of body weight or tumor outgrowth. In calu-6 xenografts, LY2835219 in combination with gemcitabine enhanced in vivo antitumor activity without a G1 cell cycle arrest, but was associated with a reduction of ribonucleotide reductase expression. These results suggest LY2835219 may be used alone or in combination with standard-of-care cytotoxic therapy. In summary, we have identified a potent, orally active small-molecule inhibitor of CDK4/6 that is active in xenograft tumors. LY2835219 is currently in clinical development. PMID:24919854

  9. Cdk4 functions in multiple cell types to control Drosophila intestinal stem cell proliferation and differentiation

    PubMed Central

    Adlesic, Mojca; Frei, Christian; Frew, Ian J.

    2016-01-01

    ABSTRACT The proliferation of intestinal stem cells (ISCs) and differentiation of enteroblasts to form mature enteroendocrine cells and enterocytes in the Drosophila intestinal epithelium must be tightly regulated to maintain homeostasis. We show that genetic modulation of CyclinD/Cdk4 activity or mTOR-dependent signalling cell-autonomously regulates enterocyte growth, which influences ISC proliferation and enteroblast differentiation. Increased enterocyte growth results in higher numbers of ISCs and defective enterocyte growth reduces ISC abundance and proliferation in the midgut. Adult midguts deficient for Cdk4 show severe disruption of intestinal homeostasis characterised by decreased ISC self-renewal, enteroblast differentiation defects and low enteroendocrine cell and enterocyte numbers. The ISC/enteroblast phenotypes result from a combination of cell autonomous and non-autonomous requirements for Cdk4 function. One non-autonomous consequence of Cdk4-dependent deficient enterocyte growth is high expression of Delta in ISCs and Delta retention in enteroblasts. We postulate that aberrant activation of the Delta–Notch pathway is a possible partial cause of lost ISC stemness. These results support the idea that enterocytes contribute to a putative stem cell niche that maintains intestinal homeostasis in the Drosophila anterior midgut. PMID:26879465

  10. Cdk4 functions in multiple cell types to control Drosophila intestinal stem cell proliferation and differentiation.

    PubMed

    Adlesic, Mojca; Frei, Christian; Frew, Ian J

    2016-01-01

    The proliferation of intestinal stem cells (ISCs) and differentiation of enteroblasts to form mature enteroendocrine cells and enterocytes in the Drosophila intestinal epithelium must be tightly regulated to maintain homeostasis. We show that genetic modulation of CyclinD/Cdk4 activity or mTOR-dependent signalling cell-autonomously regulates enterocyte growth, which influences ISC proliferation and enteroblast differentiation. Increased enterocyte growth results in higher numbers of ISCs and defective enterocyte growth reduces ISC abundance and proliferation in the midgut. Adult midguts deficient for Cdk4 show severe disruption of intestinal homeostasis characterised by decreased ISC self-renewal, enteroblast differentiation defects and low enteroendocrine cell and enterocyte numbers. The ISC/enteroblast phenotypes result from a combination of cell autonomous and non-autonomous requirements for Cdk4 function. One non-autonomous consequence of Cdk4-dependent deficient enterocyte growth is high expression of Delta in ISCs and Delta retention in enteroblasts. We postulate that aberrant activation of the Delta-Notch pathway is a possible partial cause of lost ISC stemness. These results support the idea that enterocytes contribute to a putative stem cell niche that maintains intestinal homeostasis in the Drosophila anterior midgut. PMID:26879465

  11. Proliferation and Cdk4 expression in microsatellite unstable colon cancers with TGFBR2 mutations.

    PubMed

    Grady, William M; Willis, Joseph E; Trobridge, Patty; Romero-Gallo, Judith; Munoz, Nina; Olechnowicz, Joseph; Ferguson, Kelly; Gautam, Shiva; Markowitz, Sanford D

    2006-02-01

    Approximately 15% of human colon cancers have microsatellite instability (MSI) and carry frameshift mutations in a polyadenine tract (BAT-RII) in the type II transforming growth factor beta (TGF-beta) receptor (TGFBR2), a required component of the TGF-beta receptor. The BAT-RII mutations in MSI colon cancers make the tumors resistant to the effects of TGF-beta. In cultured epithelial cells, TGF-beta can inhibit cell proliferation and induce apoptosis, and in vitro it can regulate the expression of a variety of cyclins, cyclin-dependent kinases (cdks) and cdk inhibitors. These effects are context- and tissue type-dependent, raising questions about which of these in vitro effects of TGF-beta signaling inactivation contribute to the formation of primary colon cancer. Thus, this study sought to determine the pathogenetically relevant effects of TGFBR2 inactivation in primary MSI colon cancers with mutant BAT-RII. Colon cancers with mutant BAT-RII were found to have increased proliferation compared to cancers with wild-type BAT-RII. Assessment of cdk4, cyclin D1 and p27(kip1) expression revealed that only cdk4 expression was increased in the cancers with mutant BAT-RII. In order to determine if TGFBR2 inactivation was the cause of these changes, TGFBR2 was reconstituted in an MSI colon cancer cell line, resulting in decreased proliferation and decreased cdk4 expression and kinase activity. These results suggest that TGFBR2 mutations in primary colon cancers may be responsible for the increased proliferation and cdk4 expression in these tumors and provide evidence that deregulation of cdk4 is a pathogenic in vivo consequence of TGFBR2 inactivation in primary colon cancer. PMID:16108056

  12. Expression and cellular distribution of cyclin-dependent kinase 4 (Cdk4) and connexin 43 (Cx43) in porcine oocytes before and after in vitro maturation.

    PubMed

    Kempisty, Bartosz; Ziółkowska, Agnieszka; Piotrowska, Hanna; Antosik, Paweł; Bukowska, Dorota; Zawierucha, Piotr; Jaśkowski, Jędrzej M; Brüssow, Klaus-Peter; Nowicki, Michał; Zabel, Maciej

    2014-03-01

    It is recognised that connexin 43 (Cx43) and cyclin-dependent kinase 4 (Cdk4) are involved in the cumulus cell-oocyte communication via gap junctions and the control of cell cycle progress. However, little is known about their mRNA expression pattern and encoded proteins distribution in porcine oocytes during in vitro maturation (IVM). Cumulus-oocyte complexes (COCs) were collected from 31 puberal crossbred Landrace gilts and analysed for their Cdk4 and Cx43 mRNA expression using RQ-PCR and for the respective protein expression by confocal microscopic observations. An increased Cdk4 and Cx43 mRNA expression was found in oocytes after IVM (P < 0.001 and P < 0.05, respectively). Confocal microscopic observations revealed a significant increase of Cdk4 protein expression in the cytoplasm of oocytes during the maturation process. The localisation of Cx43 changed from zona pellucida before to cytoplasm of oocytes after IVM. It is supposed that the increased expression of Cdk4 and Cx43 mRNA in oocytes after IVM is linked with the accumulation of a large amount of templates during the process of oocyte maturation. The translocation especially of Cx43 from the zona pellucida into the cytoplasm may be associated with a decrease in gap junction activity in fully grown porcine oocytes. Both Cdk4 and Cx43 can be used as 'checkpoints' of oocyte maturation. PMID:24334079

  13. Involvement of cyclin D1/CDK4 and pRb mediated by PI3K/AKT pathway activation in Pb{sup 2+}-induced neuronal death in cultured hippocampal neurons

    SciTech Connect

    Li Chenchen Xing Tairan Tang Mingliang Yong Wu Yan Dan Deng Hongmin Wang Huili Wang Ming Chen Jutao Ruan Diyun

    2008-06-15

    Lead (Pb) is widely recognized as a neurotoxicant. One of the suggested mechanisms of lead neurotoxicity is apoptotic cell death. And the mechanism by which Pb{sup 2+} causes neuronal death is not well understood. The present study sought to examine the obligate nature of cyclin D1/cyclin-dependent kinase 4 (CDK4), phosphorylation of its substrate retinoblastoma protein (pRb) and its select upstream signal phosphoinositide 3-kinase (PI3K)/AKT pathway in the death of primary cultured rat hippocampal neurons evoked by Pb{sup 2+}. Our data showed that lead treatment of primary hippocampal cultures results in dose-dependent cell death. Inhibition of CDK4 prevented Pb{sup 2+}-induced neuronal death significantly but was incomplete. In addition, we demonstrated that the levels of cyclin D1 and pRb/p107 were increased during Pb{sup 2+} treatment. These elevated expression persisted up to 48 h, returning to control levels after 72 h. We also presented pharmacological and morphological evidences that cyclin D1/CDK4 and pRb/p107 were required for such kind of neuronal death. Addition of the PI3K inhibitor LY294002 (30 {mu}M) or wortmannin (100 nM) significantly rescued the cultured hippocampal neurons from death caused by Pb{sup 2+}. And that Pb{sup 2+}-elicited phospho-AKT (Ser473) participated in the induction of cyclin D1 and partial pRb/p107 expression. These results provide evidences that cell cycle elements play a required role in the death of neurons evoked by Pb{sup 2+} and suggest that certain signaling elements upstream of cyclin D1/CDK4 are modified and/or required for this form of neuronal death.

  14. Cyclin D1-Cdk4 controls glucose metabolism independently of cell cycle progression.

    PubMed

    Lee, Yoonjin; Dominy, John E; Choi, Yoon Jong; Jurczak, Michael; Tolliday, Nicola; Camporez, Joao Paulo; Chim, Helen; Lim, Ji-Hong; Ruan, Hai-Bin; Yang, Xiaoyong; Vazquez, Francisca; Sicinski, Piotr; Shulman, Gerald I; Puigserver, Pere

    2014-06-26

    Insulin constitutes a principal evolutionarily conserved hormonal axis for maintaining glucose homeostasis; dysregulation of this axis causes diabetes. PGC-1α (peroxisome-proliferator-activated receptor-γ coactivator-1α) links insulin signalling to the expression of glucose and lipid metabolic genes. The histone acetyltransferase GCN5 (general control non-repressed protein 5) acetylates PGC-1α and suppresses its transcriptional activity, whereas sirtuin 1 deacetylates and activates PGC-1α. Although insulin is a mitogenic signal in proliferative cells, whether components of the cell cycle machinery contribute to its metabolic action is poorly understood. Here we report that in mice insulin activates cyclin D1-cyclin-dependent kinase 4 (Cdk4), which, in turn, increases GCN5 acetyltransferase activity and suppresses hepatic glucose production independently of cell cycle progression. Through a cell-based high-throughput chemical screen, we identify a Cdk4 inhibitor that potently decreases PGC-1α acetylation. Insulin/GSK-3β (glycogen synthase kinase 3-beta) signalling induces cyclin D1 protein stability by sequestering cyclin D1 in the nucleus. In parallel, dietary amino acids increase hepatic cyclin D1 messenger RNA transcripts. Activated cyclin D1-Cdk4 kinase phosphorylates and activates GCN5, which then acetylates and inhibits PGC-1α activity on gluconeogenic genes. Loss of hepatic cyclin D1 results in increased gluconeogenesis and hyperglycaemia. In diabetic models, cyclin D1-Cdk4 is chronically elevated and refractory to fasting/feeding transitions; nevertheless further activation of this kinase normalizes glycaemia. Our findings show that insulin uses components of the cell cycle machinery in post-mitotic cells to control glucose homeostasis independently of cell division. PMID:24870244

  15. Cyclin D1-CDK4 Controls Glucose Metabolism Independently of Cell Cycle Progression

    PubMed Central

    Lee, Yoonjin; Dominy, John E.; Choi, Yoon Jong; Jurczak, Michael; Tolliday, Nicola; Camporez, Joao Paulo; Chim, Helen; Lim, Ji-Hong; Ruan, Hai-Bin; Yang, Xiaoyong; Vazquez, Francisca; Sicinski, Piotr; Shulman, Gerald I.; Puigserver, Pere

    2014-01-01

    Insulin constitutes a major evolutionarily conserved hormonal axis for maintaining glucose homeostasis1-3; dysregulation of this axis causes diabetes2,4. PGC-1α links insulin signaling to the expression of glucose and lipid metabolic genes5-7. GCN5 acetylates PGC-1α and suppresses its transcriptional activity, whereas SIRT1 deacetylates and activates PGC-1α8,9. Although insulin is a mitogenic signal in proliferative cells10,11, whether components of the cell cycle machinery contribute to insulin’s metabolic action is poorly understood. Herein, we report that insulin activates cyclin D1-CDK4, which, in turn, increases GCN5 acetyltransferase activity and suppresses hepatic glucose production independently of cell cycle progression. Through a cell-based high throughput chemical screen, we identified a CDK4 inhibitor that potently decreases PGC-1α acetylation. Insulin/GSK3β signaling induces cyclin D1 protein stability via sequestering cyclin D1 in the nucleus. In parallel, dietary amino acids increase hepatic cyclin D1 mRNA transcripts. Activated cyclin D1-CDK4 kinase phosphorylates and activates GCN5, which then acetylates and inhibits PGC-1α activity on gluconeogenic genes. Loss of hepatic cyclin D1 results in increased gluconeogenesis and hyperglycemia. In diabetic models, cyclin D1-CDK4 is chronically elevated and refractory to fasting/feeding transitions; nevertheless further activation of this kinase normalizes glycemia. Our findings show that insulin uses components of the cell cycle machinery in post-mitotic cells to control glucose homeostasis independently of cell division. PMID:24870244

  16. Multipotent neurogenic fate of mesenchymal stem cell is determined by Cdk4-mediated hypophosphorylation of Smad-STAT3.

    PubMed

    Kim, Dong-Young; Lee, Janet; Kang, Dongrim; Lee, Do-Hyeong; Kim, Yoon-Ja; Hwang, Sang-Gu; Kim, Dong-Ik; Lee, Chang-Woo; Lee, Kyung-Hoon

    2016-07-01

    Cyclin-dependent kinase (Cdk) in complex with a corresponding cyclin plays a pivotal role in neurogenic differentiation. In particular, Cdk4 activity acts as a signaling switch to direct human mesenchymal stem cells (MSCs) to neural transdifferentiation. However, the molecular evidence of how Cdk4 activity converts MSCs to neurogenic lineage remains unknown. Here, we found that Cdk4 inhibition in human MSCs enriches the populations of neural stem and progenitor pools rather than differentiated glial and neuronal cell pools. Interestingly, Cdk4 inhibition directly inactivates Smads and subsequently STAT3 signaling by hypophosphorylation, and both Cdk4 and Smads levels are linked during the processes of neural transdifferentiation and differentiation. In summary, our results provide novel molecular evidence in which Cdk4 inhibition leads to directing human MSCs to a multipotent neurogenic fate by inactivating Smads-STAT3 signaling. PMID:27192561

  17. Cytotoxicity of diacetoxyscirpenol is associated with apoptosis by activation of caspase-8 and interruption of cell cycle progression by down-regulation of cdk4 and cyclin B1 in human Jurkat T cells

    SciTech Connect

    Jun, Do Youn; Kim, Jun Seok; Park, Hae Sun; Song, Woo Sun; Bae, Young Seuk; Kim, Young Ho . E-mail: ykim@knu.ac.kr

    2007-07-15

    To understand the mechanism underlying T-cell toxicity of diacetoxyscirpenol (DAS) from Fusarium sambucinum, its apoptogenic as well as growth retardation activity was investigated in human Jurkat T cells. Exposure to DAS (0.01-0.15 {mu}M) caused apoptotic DNA fragmentation along with caspase-8 activation, Bid cleavage, mitochondrial cytochrome c release, activation of caspase-9 and caspase-3, and PARP degradation, without any alteration in the levels of Fas or FasL. Under these conditions, necrosis was not accompanied. The cytotoxicity of DAS was not blocked by the anti-Fas neutralizing antibody ZB-4. Although the DAS-induced apoptotic events were completely prevented by overexpression of Bcl-xL, the cells overexpressing Bcl-xL were unable to divide in the presence of DAS, resulting from the failure of cell cycle progression possibly due to down-regulation in the protein levels of cdk4 and cyclin B1. The DAS-mediated apoptosis and activation of caspase-8, -9, and -3 were abrogated by either pan-caspase inhibitor (z-VAD-fmk) or caspase-8 inhibitor (z-IETD-fmk). While the DAS-mediated apoptosis and activation of caspase-9 and caspase-3 were slightly suppressed by the mitochondrial permeability transition pore inhibitor (CsA), both caspase-8 activation and Bid cleavage were not affected by CsA. The activated normal peripheral T cells possessed a similar susceptibility to the cytotoxicity of DAS. These results demonstrate that the T-cell toxicity of DAS is attributable to not only apoptosis initiated by caspase-8 activation and subsequent mitochondrion-dependent or -independent activation of caspase cascades, which can be regulated by Bcl-xL, but also interruption of cell cycle progression caused by down-regulation of cdk4 and cyclin B1 proteins.

  18. MEN1 tumorigenesis in the pituitary and pancreatic islet requires Cdk4 but not Cdk2.

    PubMed

    Gillam, M P; Nimbalkar, D; Sun, L; Christov, K; Ray, D; Kaldis, P; Liu, X; Kiyokawa, H

    2015-02-12

    Recent studies suggest that physiological and tumorigenic proliferation of mammalian cells is controlled by multiple cyclin-dependent kinases (CDKs) largely in tissue-specific manners. We and others previously demonstrated that adult mice deficient for the Cyclin D partner CDK4 (Cdk4(-/-) mice) exhibit hypoplasia in the pituitary and pancreatic islet due to primary postnatal defects in proliferation. Intriguingly, those neuroendocrine tissues affected in Cdk4(-/-) mice are the primary targets of tumorigenesis in the syndrome of multiple endocrine neoplasia type-1 (MEN1). Mice with heterozygous disruption of the tumor suppressor Men1 gene (Men1(+/-)) develop tumors in the pituitary, pancreatic islets and other neuroendocrine tissues, which is analogous to humans with MEN1 mutations. To explore the genetic interactions between loss of Men1 and activation of CDKs, we examined the impact of Cdk4 or Cdk2 disruption on tumorigenesis in Men1(+/-) mice. A majority of Men1(+/-) mice with wild-type CDKs developed pituitary and islet tumors by 15 months of age. Strikingly, Men1(+/-); Cdk4(-/-) mice did not develop any tumors, and their islets and pituitaries remained hypoplastic with decreased proliferation. In contrast, Men1(+/-); Cdk2(-/-) mice showed pituitary and islet tumorigenesis comparable to those in Men1(+/-) mice. Pituitaries of Men1(+/-); Cdk4(-/-) mice showed no signs of loss of heterozygosity (LOH) in the Men1 locus, whereas tumors in Men1(+/-) mice and Men1(+/-); Cdk2(-/-) mice exhibited LOH. Consistently, CDK4 knockdown in INS-1 insulinoma cells inhibited glucose-stimulated cell cycle progression with a significant decrease in phosphorylation of retinoblastoma protein (RB) at specific sites including Ser780. CDK2 knockdown had minimum effects on RB phosphorylation and cell cycle progression. These data suggest that CDK4 is a critical downstream target of MEN1-dependent tumor suppression and is required for tumorigenic proliferation in the pituitary and

  19. Artemisinin blocks prostate cancer growth and cell cycle progression by disrupting Sp1 interactions with the cyclin-dependent kinase-4 (CDK4) promoter and inhibiting CDK4 gene expression.

    PubMed

    Willoughby, Jamin A; Sundar, Shyam N; Cheung, Mark; Tin, Antony S; Modiano, Jaime; Firestone, Gary L

    2009-01-23

    Artemisinin, a naturally occurring component of Artemisia annua, or sweet wormwood, is a potent anti-malaria compound that has recently been shown to have anti-proliferative effects on a number of human cancer cell types, although little is know about the molecular mechanisms of this response. We have observed that artemisinin treatment triggers a stringent G1 cell cycle arrest of LNCaP (lymph node carcinoma of the prostate) human prostate cancer cells that is accompanied by a rapid down-regulation of CDK2 and CDK4 protein and transcript levels. Transient transfection with promoter-linked luciferase reporter plasmids revealed that artemisinin strongly inhibits CDK2 and CDK4 promoter activity. Deletion analysis of the CDK4 promoter revealed a 231-bp artemisinin-responsive region between -1737 and -1506. Site-specific mutations revealed that the Sp1 site at -1531 was necessary for artemisinin responsiveness in the context of the CDK4 promoter. DNA binding assays as well as chromatin immunoprecipitation assays demonstrated that this Sp1-binding site in the CDK4 promoter forms a specific artemisinin-responsive DNA-protein complex that contains the Sp1 transcription factor. Artemisinin reduced phosphorylation of Sp1, and when dephosphorylation of Sp1 was inhibited by treatment of cells with the phosphatase inhibitor okadaic acid, the ability of artemisinin to down-regulate Sp1 interactions with the CDK4 promoter was ablated, rendering the CDK4 promoter unresponsive to artemisinin. Finally, overexpression of Sp1 mostly reversed the artemisinin down-regulation of CDK4 promoter activity and partially reversed the cell cycle arrest. Taken together, our results demonstrate that a key event in the artemisinin anti-proliferative effects in prostate cancer cells is the transcriptional down-regulation of CDK4 expression by disruption of Sp1 interactions with the CDK4 promoter. PMID:19017637

  20. A possible usage of a CDK4 inhibitor for breast cancer stem cell-targeted therapy

    SciTech Connect

    Han, Yu Kyeong; Lee, Jae Ho; Park, Ga-Young; Chun, Sung Hak; Han, Jeong Yun; Kim, Sung Dae; Lee, Janet; Lee, Chang-Woo; Yang, Kwangmo; Lee, Chang Geun

    2013-01-25

    Highlights: ► A CDK4 inhibitor may be used for breast cancer stem cell-targeted therapy. ► The CDK4 inhibitor differentiated the cancer stem cell population (CD24{sup −}/CD44{sup +}) of MDA-MB-231. ► The differentiation of the cancer stem cells by the CDK4 inhibitor radiosensitized MDA-MB-231. -- Abstract: Cancer stem cells (CSCs) are one of the main reasons behind cancer recurrence due to their resistance to conventional anti-cancer therapies. Thus, many efforts are being devoted to developing CSC-targeted therapies to overcome the resistance of CSCs to conventional anti-cancer therapies and decrease cancer recurrence. Differentiation therapy is one potential approach to achieve CSC-targeted therapies. This method involves inducing immature cancer cells with stem cell characteristics into more mature or differentiated cancer cells. In this study, we found that a CDK4 inhibitor sensitized MDA-MB-231 cells but not MCF7 cells to irradiation. This difference appeared to be associated with the relative percentage of CSC-population between the two breast cancer cells. The CDK4 inhibitor induced differentiation and reduced the cancer stem cell activity of MDA-MB-231 cells, which are shown by multiple marker or phenotypes of CSCs. Thus, these results suggest that radiosensitization effects may be caused by reducing the CSC-population of MDA-MB-231 through the use of the CDK4 inhibitor. Thus, further investigations into the possible application of the CDK4 inhibitor for CSC-targeted therapy should be performed to enhance the efficacy of radiotherapy for breast cancer.

  1. A CDK4/6 inhibitor enhances cytotoxicity of paclitaxel in lung adenocarcinoma cells harboring mutant KRAS as well as wild-type KRAS.

    PubMed

    Zhang, Xiang-Hua; Cheng, Ying; Shin, Jung-Young; Kim, Jeong-Oh; Oh, Ji-Eun; Kang, Jin-Hyoung

    2013-07-01

    The KRAS gain-of-function mutation confers intrinsic resistance to targeted anti-cancer drugs and cytotoxic chemotherapeutic agents, ultimately leading to treatment failure. KRAS mutation frequency in lung adenocarcinoma is ~15-30%. Novel therapeutic strategies should be developed to improve clinical outcomes in these cases. Deregulation of the p16/cyclin-dependent kinase (CDK) 4/retinoblastoma (Rb) pathway is frequently observed in various cancers and it represents an attractive therapeutic target. We compared the anti-tumor efficacy of genetically knocked-down CDK4 and a pharmacological inhibitor of CDK4/6, CINK4, in KRAS mutation-positive lung adenocarcinoma cells. We also investigated changes in anti-proliferative activity and downstream molecules with these treatments in combination with paclitaxel. CDK4 short interfering RNA (siRNA) significantly increased paclitaxel sensitivity in KRAS mutation-positive H23 cells. CINK4 demonstrated concentration- and time-dependent anti-proliferative activity in 5 adenocarcinoma lines. CINK4 induced G 1 arrest by downregulating the p16/cyclin D1/Rb pathway, resulting in apoptotic induction via increased expression of cleaved caspase3, cleaved PARP and Bax. Combined CINK4 and paclitaxel produced synergistic anti-proliferative activity and increased apoptosis through reduced cyclin D1 and Bcl-2 in KRAS mutation-positive cancer cells. These data suggest CDK4 is a promising target for development of anti-cancer drugs and CINK4 combined with paclitaxel may be an effective therapeutic strategy for enhancing anti-tumor efficacy in KRAS mutation-positive lung adenocarcinoma. PMID:23792647

  2. Overcoming Endocrine Resistance in Hormone-Receptor Positive Advanced Breast Cancer-The Emerging Role of CDK4/6 Inhibitors

    PubMed Central

    O’Sullivan, Ciara C

    2015-01-01

    Dysregulation of the cyclin D and cyclin-dependent kinase (CDK) pathway in cancer cells may inhibit senescence and promote cellular proliferation. By using various different mechanisms, malignant cells may increase cyclin D-dependent activity. The cyclin D-cyclin-dependent kinases 4 and 6 (CDK4/6)-retinoblastoma (Rb) pathway controls the cell cycle restriction point, and is commonly dysregulated in breast cancer; making it a rational target for anticancer therapy. To date, three oral highly selective cyclin-dependent kinase 4/6 inhibitors (CDK4/6i) are in various stages of clinical development: PD0332991 (palbociclib), LEE011 (ribociclib) and LY2835219 (abemaciclib). Results from phase I, II and III trials in hormone-receptor (HR)-positive breast cancer have been encouraging, demonstrating convincing efficacy and a tolerable side-effect profile (mainly uncomplicated neutropenia). This article will review the preclinical and clinical development of the CDK4/6i, as well as reviewing the existing preclinical evidence regarding combination of these agents with chemotherapy and other targeted therapies. Future and ongoing clinical trials, which may expand the potential application of these agents, will also be discussed. In summary, CDK4/6i are exciting compounds which may change the therapeutic landscape of HR-positive breast cancer. PMID:26726315

  3. Overcoming Therapeutic Resistance in HER2-Positive Breast Cancers with CDK4/6 Inhibitors.

    PubMed

    Goel, Shom; Wang, Qi; Watt, April C; Tolaney, Sara M; Dillon, Deborah A; Li, Wei; Ramm, Susanne; Palmer, Adam C; Yuzugullu, Haluk; Varadan, Vinay; Tuck, David; Harris, Lyndsay N; Wong, Kwok-Kin; Liu, X Shirley; Sicinski, Piotr; Winer, Eric P; Krop, Ian E; Zhao, Jean J

    2016-03-14

    Using transgenic mouse models, cell line-based functional studies, and clinical specimens, we show that cyclin D1/CDK4 mediate resistance to targeted therapy for HER2-positive breast cancer. This is overcome using CDK4/6 inhibitors. Inhibition of CDK4/6 not only suppresses Rb phosphorylation, but also reduces TSC2 phosphorylation and thus partially attenuates mTORC1 activity. This relieves feedback inhibition of upstream EGFR family kinases, resensitizing tumors to EGFR/HER2 blockade. Consequently, dual inhibition of EGFR/HER2 and CDK4/6 invokes a more potent suppression of TSC2 phosphorylation and hence mTORC1/S6K/S6RP activity. The suppression of both Rb and S6RP enhances G1 arrest and a phenotype resembling cellular senescence. In vivo, CDK4/6 inhibitors sensitize patient-derived xenograft tumors to HER2-targeted therapies and delay tumor recurrence in a transgenic model of HER2-positive breast cancer. PMID:26977878

  4. Early Adaptation and Acquired Resistance to CDK4/6 Inhibition in Estrogen Receptor-Positive Breast Cancer.

    PubMed

    Herrera-Abreu, Maria Teresa; Palafox, Marta; Asghar, Uzma; Rivas, Martín A; Cutts, Rosalind J; Garcia-Murillas, Isaac; Pearson, Alex; Guzman, Marta; Rodriguez, Olga; Grueso, Judit; Bellet, Meritxell; Cortés, Javier; Elliott, Richard; Pancholi, Sunil; Baselga, José; Dowsett, Mitch; Martin, Lesley-Ann; Turner, Nicholas C; Serra, Violeta

    2016-04-15

    Small-molecule inhibitors of the CDK4/6 cell-cycle kinases have shown clinical efficacy in estrogen receptor (ER)-positive metastatic breast cancer, although their cytostatic effects are limited by primary and acquired resistance. Here we report that ER-positive breast cancer cells can adapt quickly to CDK4/6 inhibition and evade cytostasis, in part, via noncanonical cyclin D1-CDK2-mediated S-phase entry. This adaptation was prevented by cotreatment with hormone therapies or PI3K inhibitors, which reduced the levels of cyclin D1 (CCND1) and other G1-S cyclins, abolished pRb phosphorylation, and inhibited activation of S-phase transcriptional programs. Combined targeting of both CDK4/6 and PI3K triggered cancer cell apoptosis in vitro and in patient-derived tumor xenograft (PDX) models, resulting in tumor regression and improved disease control. Furthermore, a triple combination of endocrine therapy, CDK4/6, and PI3K inhibition was more effective than paired combinations, provoking rapid tumor regressions in a PDX model. Mechanistic investigations showed that acquired resistance to CDK4/6 inhibition resulted from bypass of cyclin D1-CDK4/6 dependency through selection of CCNE1 amplification or RB1 loss. Notably, although PI3K inhibitors could prevent resistance to CDK4/6 inhibitors, they failed to resensitize cells once resistance had been acquired. However, we found that cells acquiring resistance to CDK4/6 inhibitors due to CCNE1 amplification could be resensitized by targeting CDK2. Overall, our results illustrate convergent mechanisms of early adaptation and acquired resistance to CDK4/6 inhibitors that enable alternate means of S-phase entry, highlighting strategies to prevent the acquisition of therapeutic resistance to these agents. Cancer Res; 76(8); 2301-13. ©2016 AACR. PMID:27020857

  5. Caco-2 intestinal cell differentiation is associated with G1 arrest and suppression of CDK2 and CDK4.

    PubMed

    Ding, Q M; Ko, T C; Evers, B M

    1998-11-01

    The cellular mechanisms regulating intestinal proliferation and differentiation remain largely undefined. Previously, we showed an early induction of the cyclin-dependent kinase (CDK) inhibitor p21(Waf1/Cip1) in Caco-2 cells, a human colon cancer line that spontaneously differentiates into a small bowel phenotype. The purpose of our present study was to assess the timing of cell cycle arrest in relation to differentiation in Caco-2 cells and to examine the mechanisms responsible for CDK inactivation. Caco-2 cells undergo a relative G1/S block and cease to proliferate at day 3 postconfluency; an increase in the activity of terminally differentiated brush-border enzymes (sucrase and alkaline phosphatase) was noted at day 6 postconfluency. Cell cycle block was associated with suppression of both CDK2 and CDK4 activities, which are important for G1/S progression. Treatment of the CDK immune complexes with the detergent deoxycholate (DOC) resulted in restoration of CDK2, but not CDK4, activity at day 3 postconfluency, suggesting the presence of inhibitory protein(s) binding to the cyclin/CDK2 complex at this time point. An increased binding of p21(Waf1/Cip1) to CDK2 complexes at day 3 postconfluency was noted, suggesting a potential role for p21(Waf1/Cip1) in CDK2 inactivation; however, immunodepletion of p21(Waf1/Cip1) from Caco-2 protein extracts demonstrated that p21(Waf1/Cip1) is only partially responsible for CDK2 suppression at day 3 postconfluency. A decrease in the cyclin E/CDK2 complex appears to contribute to the CDK2 inactivation noted at days 6 and 12 postconfluency. Taken together, our results suggest that multiple mechanisms contribute to CDK suppression during Caco-2 cell differentiation. Inhibition of CDK2 and CDK4 leads to G1 arrest and inhibition of proliferation that precede Caco-2 cell differentiation. PMID:9814966

  6. Dual CDK4/CDK6 Inhibition Induces Cell Cycle Arrest and Senescence in Neuroblastoma

    PubMed Central

    Rader, JulieAnn; Russell, Mike R.; Hart, Lori S.; Nakazawa, Michael S.; Belcastro, Lili T.; Martinez, Daniel; Li, Yimei; Carpenter, Erica L.; Attiyeh, Edward F.; Diskin, Sharon J.; Kim, Sunkyu; Parasuraman, Sudha; Caponigro, Giordano; Schnepp, Robert W.; Wood, Andrew C.; Pawel, Bruce; Cole, Kristina A.; Maris, John M.

    2013-01-01

    Purpose Neuroblastoma is a pediatric cancer that continues to exact significant morbidity and mortality. Recently, a number of cell cycle proteins, particularly those within the Cyclin D/CDK4/CDK6/RB network, have been shown to exert oncogenic roles in neuroblastoma, suggesting that their therapeutic exploitation might improve patient outcomes. Experimental Procedures We evaluated the effect of dual CDK4/CDK6 inhibition on neuroblastoma viability using LEE011, a highly specific CDK4/6 inhibitor. Results Treatment with LEE011 significantly reduced proliferation in 12 of 17 human neuroblastoma-derived cell lines by inducing cytostasis at nanomolar concentrations (mean IC50 = 307 ± 68 nM in sensitive lines). LEE011 caused cell cycle arrest and cellular senescence that was attributed to dose-dependent decreases in phosphorylated RB and FOXM1, respectively. In addition, responsiveness of neuroblastoma xenografts to LEE011 translated to the in vivo setting in that there was a direct correlation of in vitro IC50 values with degree of subcutaneous xenograft growth delay. While our data indicate that neuroblastomas sensitive to LEE011 were more likely to contain genomic amplification of MYCN (p = 0.01), the identification of additional clinically accessible biomarkers is of high importance. Conclusions Taken together, our data show that LEE011 is active in a large subset of neuroblastoma cell line and xenograft models, and supports the clinical development of this CDK4/6 inhibitor as a therapy for patients with this disease. PMID:24045179

  7. Simulation of Different Truncated p16INK4a Forms and In Silico Study of Interaction with Cdk4

    PubMed Central

    Fahham, Najmeh; Ghahremani, Mohammad Hossein; Sardari, Soroush; Vaziri, Behrouz; Ostad, Seyed Nasser

    2008-01-01

    Protein-protein interactions studies can greatly increase the amount of structural and functional information pertaining to biologically active molecules and processes. The information obtained from such studies can lead to design and application of new modification in order to obtain a desired bioactivity. Many application packages and servers performing docking, such as HEX, DOT, AUTODOCK, and ZDOCK are now available for predicting the lowest free energy state of a protein complex. In this study, we have focused on cyclin-dependent kinase 4 (Cdk4), a key molecule in the regulation of cell cycle progression at the G1-S phase restriction point and p16INK4a, a tumor suppressor which inhibits Cdk4 activity. Truncated structures were created to find the more critical regions of p16 for interaction. The tertiary structures were determined by ProSAL, GENO3D Web Server. We evaluated their interactions with Cdk4 using two docking systems, HEX 4.5 and DOT 1. Calculations were performed on a high-speed computer. Minimizations and visualizations were carried out by PdbViewer 3.7. Considering shape and shape/electrostatic total energy, structures containing ANK II, III and IV motifs that lack the N-terminal region of the full length p16 molecule showed the best fit complexes among the p16 truncated forms. The free energies were compatible with that of p16 full length original form, the full length. It seems that the N-terminal of the molecule is not crucial for the interaction since the truncated structure containing only this region did not show a good total energy. PMID:19352455

  8. Targeting the cyclin D-cyclin-dependent kinase (CDK) 4/6-retinoblastoma pathway with selective CDK 4/6 inhibitors in hormone receptor-positive breast cancer: rationale, current status, and future directions.

    PubMed

    Spring, Laura; Bardia, Aditya; Modi, Shanu

    2016-01-01

    Dysregulation of the cyclin D-cyclin-dependent kinase (CDK) 4/6-INK4-retinoblastoma (Rb) pathway is an important contributor to endocrine therapy resistance. Recent clinical development of selective inhibitors of CDK4 and CDK6 kinases has led to renewed interest in cell cycle regulators, following experience with relatively non-selective pan-CDK inhibitors that often resulted in limited activity and poor safety profiles in the clinic. The highly selective oral CDK 4/6 inhibitors palbociclib (PD0332991), ribociclib (LEE011), and abemaciclib (LY2835219) are able to inhibit the proliferation of Rb-positive tumor cells and have demonstrated dose-dependent growth inhibition in ER+ breast cancer models. In metastatic breast cancer, all three agents are being explored in combination with endocrine therapy in Phase III studies. Results so far indicated promising efficacy and manageable safety profiles, and led to the FDA approval of palbociclib. Phase II-III studies of these agents, in combination with endocrine therapy, are also underway in early breast cancer in the neoadjuvant and adjuvant settings. Selective CDK 4/6 inhibitors are also being investigated with other targeted agents or chemotherapy in the advanced setting. This article reviews the rationale for targeting cyclin D-CDK 4/6 in hormone receptor-positive (HR+) breast cancer, provides an overview of the available preclinical and clinical data with CDK 4/6 inhibitors in breast cancer to date, and summarizes the main features of ongoing clinical trials of these new agents in breast cancer. Future trials evaluating further combination strategies with CDK 4/6 backbone and translational studies refining predictive biomarkers are needed to help personalize the optimal treatment regimen for individual patients with ER+ breast cancer. PMID:26896604

  9. Targeting the AKT/GSK3{beta}/Cyclin D1/Cdk4 Survival Signaling Pathway for Eradication of Tumor Radioresistance Acquired by Fractionated Radiotherapy

    SciTech Connect

    Shimura, Tsutomu; Kakuda, Satoshi; Ochiai, Yasushi; Kuwahara, Yoshikazu; Takai, Yoshihiro; Fukumoto, Manabu

    2011-06-01

    Purpose: Radioresistance is a major cause of treatment failure of radiotherapy (RT) in human cancer. We have recently revealed that acquired radioresistance of tumor cells induced by fractionated radiation is attributable to cyclin D1 overexpression as a consequence of the downregulation of GSK3{beta}-dependent cyclin D1 proteolysis mediated by a constitutively activated serine-threonine kinase, AKT. This prompted us to hypothesize that targeting the AKT/GSK3{beta}/cyclin D1 pathway may improve fractionated RT by suppressing acquired radioresistance of tumor cells. Methods and Materials: Two human tumor cell lines with acquired radioresistance were exposed to X-rays after incubation with either an AKT inhibitor, AKT/PKB signaling inhibitor-2 (API-2), or a Cdk4 inhibitor (Cdk4-I). Cells were then subjected to immunoblotting, clonogenic survival assay, cell growth analysis, and cell death analysis with TUNEL and annexin V staining. In vivo radiosensitivity was assessed by growth of human tumors xenografted into nude mice. Results: Treatment with API-2 resulted in downregulation of cyclin D1 expression in cells with acquired radioresistance. Cellular radioresistance disappeared completely both in vitro and in vivo with accompanying apoptosis when treated with API-2. Furthermore, inhibition of cyclin D1/Cdk4 by Cdk4-I was sufficient for abolishing radioresistance. Treatment with either API-2 or Cdk4-I was also effective in suppressing resistance to cis-platinum (II)-diamine-dichloride in the cells with acquired radioresistance. Interestingly, the radiosensitizing effect of API-2 was canceled by overexpression of cyclin D1 whereas Cdk4-I was still able to sensitize cells with cyclin D1 overexpression. Conclusion: Cyclin D1/Cdk4 is a critical target of the AKT survival signaling pathway responsible for tumor radioresistance. Targeting the AKT/GSK3{beta}/cyclin D1/Cdk4 pathway would provide a novel approach to improve fractionated RT and would have an impact on tumor

  10. Adenosine induces cell cycle arrest and apoptosis via cyclinD1/Cdk4 and Bcl-2/Bax pathways in human ovarian cancer cell line OVCAR-3.

    PubMed

    Shirali, Saeid; Aghaei, Mahmoud; Shabani, Mahdi; Fathi, Mojtaba; Sohrabi, Majid; Moeinifard, Marzieh

    2013-04-01

    Adenosine is a regulatory molecule with widespread physiological effects in almost every cells and acts as a potent regulator of cell growth. Adenosine has been shown to inhibit cell growth and induce apoptosis in the several cancer cells via caspase activation and Bcl-2/Bax pathway. The present study was designed to understand the mechanism underlying adenosine-induced apoptosis in the OVCAR-3 human ovarian cancer cells. MTT viability, BrdU and cell counting assays were used to study the cell proliferation effect of adenosine in presence of adenosine deaminase inhibitor and the nucleoside transporter inhibitor. Cell cycle analysis, propidium iodide and annexin V staining, caspase-3 activity assay, cyclinD1, Cdk4, Bcl-2 and Bax protein expressions were assessed to detect apoptosis. Adenosine significantly inhibited cell proliferation in a concentration-dependent manner in OVCAR-3 cell line. Adenosine induced cell cycle arrest in G0/G1 phase via Cdk4/cyclinD1-mediated pathway. Adenosine induced apoptosis, which was determined by Annexin V-FITC staining and increased sub-G1 population. Moreover, down-regulation of Bcl-2 protein expression, up-regulation of Bax protein expression and activation of caspase-3 were observed in response to adenosine treatment. The results of this study suggest that extracellular adenosine induced G1 cell cycle arrest and apoptosis in ovarian cancer cells via cyclinD1/ Cdk4 and Bcl-2/Bax pathways and caspase-3 activation. These data might suggest that adenosine could be used as an agent for the treatment of ovarian cancer. PMID:23345014

  11. Novel inhibitors of nuclear transport cause cell cycle arrest and decrease cyst growth in ADPKD associated with decreased CDK4 levels.

    PubMed

    Tan, Matthew; Wettersten, Hiromi I; Chu, Kristy; Huso, David L; Watnick, Terry; Friedlander, Sharon; Landesman, Yosef; Weiss, Robert H

    2014-12-01

    Autosomal-dominant polycystic kidney disease (ADPKD) is a progressive, proliferative renal disease. Kidneys from ADPKD patients are characterized by the presence of cysts that are marked by enhanced proliferation and apoptosis of renal tubular epithelial cells. Current treatment of this disease is supportive, as there are few if any clinically validated targeted therapeutics. Given the parallels between cystic disease and cancer, and in light of our findings of the efficacy of the nuclear transport inhibitors in kidney cancer, which has similarities to ADPKD, we asked whether such inhibitors show utility in ADPKD. In this study, we tested selective inhibitors of nuclear export (SINE) in two human ADPKD cell lines and in an in vivo mouse model of ADPKD. After effective downregulation of a nuclear exporter, exportin 1 (XPO1), with KPT-330, both cell lines showed dose-dependent inhibition of cell proliferation through G₀/G₁ arrest associated with downregulation of CDK4, with minimal apoptosis. To analyze mechanisms of CDK4 decrease by XPO1 inhibition, localization of various XPO1 target proteins was examined, and C/EBPβ was found to be localized in the nucleus by XPO1 inhibition, resulting in an increase of C/EBPα, which activates degradation of CDK4. Furthermore, inhibition of XPO1 with the parallel inhibitor KPT-335 attenuated cyst growth in vivo in the PKD1 mutant mouse model Pkd1(v/v). Thus, inhibition of nuclear export by KPT-330, which has shown no adverse effects in renal serum chemistries and urinalyses in animal models, and which is already in phase 1 trials for cancers, will be rapidly translatable to human ADPKD. PMID:25234309

  12. Downregulation of cyclin D1-CDK4 protein in human embryonic lung fibroblasts (HELF) induced by silica is mediated through the ERK and JNK pathway.

    PubMed

    Shen, Fuhai; Fan, Xueyun; Liu, Bingci; Jia, Xiaowei; Gao, Ai; Du, Hongju; Ye, Meng; You, Baorong; Huang, Chuanshu; Shi, Xianglin

    2008-10-01

    Silica is a factor in the induction of acute injury and chronic pulmonary fibrosis. In 1996, silica was also listed as a human carcinogen by the International Agency for Research on Cancer (IARC). However, the molecular mechanisms involved in its pathologic effects are not well understood. We found that exposure of human embryonic lung fibroblasts (HELF) to crystalline silica for 2h decreased cyclin D1 and cyclin-dependent kinase 4 (CDK4) expression levels. Extracellular signal-regulated protein kinase (ERKs), c-Jun NH2-terminal amino kinase (JNKs), and p38 kinase, as well as their downstream transcription factor, AP-1, had different effects on the regulation of expression levels of cyclin D1 and CDK4 alterations induced by silica. Silica activates multiple signal transduction pathways involved in coordinating cellular responses to stress. We established the requirements for ERK and JNK, members of the mitogen-activated protein kinase (MAPK) family, in mediating G1 phase arrest of HELF induced by silica. Silica treatment activated ERK in a dose-dependent manner. AG126 (a chemical inhibitor of the ERK signaling pathway) and the dominant negative mutant of ERK2 (a molecular inhibitor of ERK2) prevented decreases in cyclin D1 and CDK4 expression levels. A chemical inhibitor of JNK, SP600125, prevented the decreased expression of both cyclin D1 and CDK4, whereas SB203580, a chemical inhibitor of p38, did not. Interestingly, curcumin prevented the decrease in DK4 expression, but not in cyclin D1. These results demonstrate that ERKs and JNKs are responsible for the decrease of cyclin D1 and CDK4 expression levels in HELF induced by silica. Activator protein-1 (AP-1) was responsible for the decrease of CDK4 expression level, but not that of cyclin D1. The findings help to explain the mechanisms of diseases induced by silica. PMID:18703151

  13. CDKN2A/p16 loss implicates CDK4 as a therapeutic target in imatinib-resistant dermatofibrosarcoma protuberans

    PubMed Central

    Eilers, Grant; Czaplinski, Jeffrey T.; Mayeda, Mark; Bahri, Nacef; Tao, Derrick; Zhu, Meijun; Hornick, Jason L.; Lindeman, Neal I.; Sicinska, Ewa; Wagner, Andrew J.; Fletcher, Jonathan A.; Mariño-Enriquez, Adrian

    2015-01-01

    Dermatofibrosarcoma protuberans (DFSP) is an aggressive PDGFB-dependent cutaneous sarcoma characterized by infiltrative growth and frequent local recurrences. Some DFSP progress to a higher-grade fibrosarcomatous form, with rapid growth and increased risk of metastasis. Imatinib provides clinical benefit in ~50% of patients with unresectable or metastatic DFSP. However, efficacious medical therapies have not been developed for imatinib-resistant DFSP. We established a model of imatinib-resistant DFSP, and evaluated CDK4/6 inhibition as a genomically-credentialed targeted therapy. DFSP105, an imatinib-resistant human cell line, was established from a fibrosarcomatous DFSP (FS-DFSP), and was studied by SNP arrays and sequencing to identify targetable genomic alterations. Findings were validated in vitro and in vivo, and confirmed in a series including 12 DFSP and 6 FS-DFSP. SNP analysis of DFSP105 revealed a homozygous deletion encompassing CDKN2A and CDKN2B. The resultant p16 loss implicated CDK4/6 as a potential therapeutic target in DFSP. We further demonstrated CDKN2A homozygous deletion in 1/12 conventional DFSP and 2/6 FS-DFSP, while p16 expression was lost in 4/18 DFSP. In vitro treatment of DFSP105 with two structurally distinct selective CDK4/6 inhibitors, PD-0332991 and LEE011, led to inhibition of RB1 phosphorylation and inhibition of proliferation (GI50 160nM and 276nM, respectively). In vivo treatment of DFSP105 with PD-0332991 (150mg/kg) inhibited xenograft growth in mice, in comparison with imatinib-treated or untreated tumors. In conclusion, CDKN2A deletion can contribute to DFSP progression. CDK4/6 inhibition is a preclinically effective treatment against p16-negative, imatinib-resistant FS-DFSP, and should be evaluated as a therapeutic strategy in patients with unresectable or metastatic imatinib-resistant DFSP. PMID:25852058

  14. Clinical Development of the CDK4/6 Inhibitors Ribociclib and Abemaciclib in Breast Cancer.

    PubMed

    Barroso-Sousa, Romualdo; Shapiro, Geoffrey I; Tolaney, Sara M

    2016-06-01

    Clinical and preclinical data support a significant role for inhibitors of the cyclin-dependent kinases (CDKs) 4 and 6 in the treatment of patients with breast cancer. Recently, based on data showing improvement in progression-free survival, the use of palbociclib (Ibrance; Pfizer, Inc.) in combination with endocrine agents was approved to treat patients with hormone receptor-positive advanced disease. Importantly, 2 other CDK4/6 inhibitors, abemaciclib (LY2835219; Lilly) and ribociclib (LEE011; Novartis), are in the late stage of clinical development. In this review, we will focus on clinical data on these 2 new drugs, highlighting their differences compared to palbociclib in terms of single-agent activity, central nervous system penetration, and common adverse events. In addition, we will present the ongoing clinical trials and discuss future directions in the field. PMID:27493615

  15. Structural requirements of pyrido[2,3-d]pyrimidin-7-one as CDK4/D inhibitors: 2D autocorrelation, CoMFA and CoMSIA analyses.

    PubMed

    Caballero, Julio; Fernández, Michael; González-Nilo, Fernando D

    2008-06-01

    2D autocorrelation, comparative molecular field analysis (CoMFA) and comparative molecular similarity indices analysis (CoMSIA) were undertaken for a series of pyrido[2,3-d]pyrimidin-7-ones to correlate cyclin-dependent kinase (CDK) cyclin D/CDK4 inhibition with 2D and 3D structural properties of 60 known compounds. QSAR models with considerable internal as well as external predictive ability were obtained. The relevant 2D autocorrelation descriptors for modeling CDK4/D inhibitory activity were selected by linear and nonlinear genetic algorithms (GAs) using multiple linear regression (MLR) and Bayesian-regularized genetic neural network (BRGNN) approaches, respectively. Both models showed good predictive statistics; but BRGNN model enables better external predictions. A weight-based input ranking scheme and Kohonen self-organized maps (SOMs) were carried out to interpret the final net weights. The 2D autocorrelation space brings different descriptors for CDK4/D inhibition, and suggests the atomic properties relevant for the inhibitors to interact with CDK4/D active site. CoMFA and CoMSIA analyses were developed with a focus on interpretative ability using coefficient contour maps. CoMSIA produced significantly better results. The results indicate a strong correlation between the inhibitory activity of the modeled compounds and the electrostatic and hydrophobic fields around them. PMID:18468903

  16. CDK2 activation in mouse epidermis induces keratinocyte proliferation but does not affect skin tumor development.

    PubMed

    Macias, Everardo; Miliani de Marval, Paula L; De Siervi, Adriana; Conti, Claudio J; Senderowicz, Adrian M; Rodriguez-Puebla, Marcelo L

    2008-08-01

    It has been widely assumed that elevated CDK2 kinase activity plays a contributory role in tumorigenesis. We have previously shown that mice overexpressing CDK4 under control of the keratin 5 promoter (K5CDK4 mice) develop epidermal hyperplasia and increased susceptibility to squamous cell carcinomas. In this model, CDK4 overexpression results in increased CDK2 activity associated with the noncatalytic function of CDK4, sequestration of p21(Cip1) and p27(Kip1). Furthermore, we have shown that ablation of Cdk2 reduces Ras-Cdk4 tumorigenesis, suggesting that increased CDK2 activity plays an important role in Ras-mediated tumorigenesis. To investigate this hypothesis, we generated two transgenic mouse models of elevated CDK2 kinase activity, K5Cdk2 and K5Cdk4(D158N) mice. The D158N mutation blocks CDK4 kinase activity without interfering with its binding capability. CDK2 activation via overexpression of CDK4(D158N), but not of CDK2, resulted in epidermal hyperplasia. We observed elevated levels of p21(Cip1) in K5Cdk2, but not in K5Cdk4(D158N), epidermis, suggesting that CDK2 overexpression elicits a p21(Cip1) response to maintain keratinocyte homeostasis. Surprisingly, we found that neither CDK2 overexpression nor the indirect activation of CDK2 enhanced skin tumor development. Thus, although the indirect activation of CDK2 is sufficient to induce keratinocyte hyperproliferation, activation of CDK2 alone does not induce malignant progression in Ras-mediated tumorigenesis. PMID:18599613

  17. Caenorhabditis elegans cyclin D/CDK4 and cyclin E/CDK2 induce distinct cell cycle re-entry programs in differentiated muscle cells.

    PubMed

    Korzelius, Jerome; The, Inge; Ruijtenberg, Suzan; Prinsen, Martine B W; Portegijs, Vincent; Middelkoop, Teije C; Groot Koerkamp, Marian J; Holstege, Frank C P; Boxem, Mike; van den Heuvel, Sander

    2011-11-01

    Cell proliferation and differentiation are regulated in a highly coordinated and inverse manner during development and tissue homeostasis. Terminal differentiation usually coincides with cell cycle exit and is thought to engage stable transcriptional repression of cell cycle genes. Here, we examine the robustness of the post-mitotic state, using Caenorhabditis elegans muscle cells as a model. We found that expression of a G1 Cyclin and CDK initiates cell cycle re-entry in muscle cells without interfering with the differentiated state. Cyclin D/CDK4 (CYD-1/CDK-4) expression was sufficient to induce DNA synthesis in muscle cells, in contrast to Cyclin E/CDK2 (CYE-1/CDK-2), which triggered mitotic events. Tissue-specific gene-expression profiling and single molecule FISH experiments revealed that Cyclin D and E kinases activate an extensive and overlapping set of cell cycle genes in muscle, yet failed to induce some key activators of G1/S progression. Surprisingly, CYD-1/CDK-4 also induced an additional set of genes primarily associated with growth and metabolism, which were not activated by CYE-1/CDK-2. Moreover, CYD-1/CDK-4 expression also down-regulated a large number of genes enriched for catabolic functions. These results highlight distinct functions for the two G1 Cyclin/CDK complexes and reveal a previously unknown activity of Cyclin D/CDK-4 in regulating metabolic gene expression. Furthermore, our data demonstrate that many cell cycle genes can still be transcriptionally induced in post-mitotic muscle cells, while maintenance of the post-mitotic state might depend on stable repression of a limited number of critical cell cycle regulators. PMID:22102824

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

    PubMed Central

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

    2016-01-01

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

  19. Artemisinin triggers a G1 cell cycle arrest of human Ishikawa endometrial cancer cells and inhibits Cyclin Dependent Kinase-4 promoter activity and expression by disrupting NF-kB transcriptional signaling

    PubMed Central

    Tran, Kalvin Q.; Tin, Antony S.; Firestone, Gary L.

    2014-01-01

    Relatively little is known about the anti-proliferative effects of Artemisinin, a naturally occurring anti-malarial compound from Artemisia annua, or sweet wormwood, in human endometrial cancer cells. Artemisinin induced a G1 cell cycle arrest in cultured human Ishikawa endometrial cancer cells and down regulated CDK2 and CDK4 transcript and protein levels. Analysis of CDK4 promoter-luciferase reporter constructs showed that the artemisinin ablation of CDK4 gene expression was accounted for by the loss of CDK4 promoter activity. Chromatin immunoprecipitation demonstrated that artemisinin inhibited nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) subunit p65 and p50 interactions with the endogenous Ishikawa cell CDK4 promoter. Coimmunoprecipitation revealed that artemisinin disrupts endogenous p65 and p50 nuclear translocation via increased protein-protein interactions with IκB-α, an NF-κB inhibitor, and disrupts its interaction with the CDK4 promoter, leading to a loss of CDK4 gene expression. Artemisinin treatment stimulated the cellular levels of IκB-α protein without altering the level of IκB-α transcripts. Finally, expression of exogenous p65 resulted in the accumulation of this NF-κB subunit in the nucleus of artemisinin treated and untreated cells, reversed the artemisinin down-regulation of CDK4 protein expression and promoter activity and prevented the artemisinin induced G1 cell cycle arrest. Taken together, our results demonstrate that a key event in the artemisinin anti-proliferative effects in endometrial cancer cells is the transcriptional down-regulation of CDK4 expression by disruption of NF-κB interactions with the CDK4 promoter. PMID:24296733

  20. Artemisinin triggers a G1 cell cycle arrest of human Ishikawa endometrial cancer cells and inhibits cyclin-dependent kinase-4 promoter activity and expression by disrupting nuclear factor-κB transcriptional signaling.

    PubMed

    Tran, Kalvin Q; Tin, Antony S; Firestone, Gary L

    2014-03-01

    Relatively little is known about the antiproliferative effects of artemisinin, a naturally occurring antimalarial compound from Artemisia annua, or sweet wormwood, in human endometrial cancer cells. Artemisinin induced a G1 cell cycle arrest in cultured human Ishikawa endometrial cancer cells and downregulated cyclin-dependent kinase-2 (CDK2) and CDK4 transcript and protein levels. Analysis of CDK4 promoter-luciferase reporter constructs showed that the artemisinin ablation of CDK4 gene expression was accounted for by the loss of CDK4 promoter activity. Chromatin immunoprecipitation demonstrated that artemisinin inhibited nuclear factor κ-light-chain-enhancer of activated B cells (NF-κB) subunit p65 and p50 interactions with the endogenous Ishikawa cell CDK4 promoter. Coimmunoprecipitation revealed that artemisinin disrupts endogenous p65 and p50 nuclear translocation through increased protein-protein interactions with IκB-α, an NF-κB inhibitor, and disrupts its interaction with the CDK4 promoter, leading to a loss of CDK4 gene expression. Artemisinin treatment stimulated the cellular levels of IκB-α protein without altering the level of IκB-α transcripts. Finally, expression of exogenous p65 resulted in the accumulation of this NF-κB subunit in the nucleus of artemisinin-treated and artemisinin-untreated cells, reversed the artemisinin downregulation of CDK4 protein expression and promoter activity, and prevented the artemisinin-induced G1 cell cycle arrest. Taken together, our results demonstrate that a key event in the artemisinin antiproliferative effects in endometrial cancer cells is the transcriptional downregulation of CDK4 expression by disruption of NF-κB interactions with the CDK4 promoter. PMID:24296733

  1. Kinase inhibitor screening identifies CDK4 as a potential therapeutic target for melanoma

    PubMed Central

    MAHGOUB, T.; EUSTACE, A.J.; COLLINS, D.M.; WALSH, N.; O'DONOVAN, N.; CROWN, J.

    2015-01-01

    Despite recent advances in targeted therapies and immunotherapies metastatic melanoma remains only rarely curable. The objective of the present study was to identify novel therapeutic targets for metastatic melanoma. A library of 160 well-characterised and potent protein kinase inhibitors was screened in the BRAF mutant cell line Sk-Mel-28, and the NRAS mutant Sk-Mel-2, using proliferation assays. Of the 160 inhibitors tested, 20 achieved >50% growth inhibition in both cell lines. Six of the 20 were cyclin dependent kinase (CDK) inhibitors, including two CDK4 inhibitors. Fascaplysin, a synthetic CDK4 inhibitor, was further tested in 8 melanoma cell lines. The concentration of fascaplysin required to inhibit growth by 50% (IC50 value) ranged from 0.03 to 0.22 μM. Fascaplysin also inhibited clonogenic growth and induced apoptosis. Sensitivity to PD0332991, a therapeutic CDK4/6 inhibitor was also evaluated in the melanoma cell lines. PD0332991 IC50 values ranged from 0.13 to 2.29 μM. Similar to fascaplysin, PD0332991 inhibited clonogenic growth of melanoma cells and induced apoptosis. Higher levels of CDK4 protein correlated with lower sensitivity to PD0332991 in the cell lines. Combined treatment with PD0332991 and the BRAF inhibitor PLX4032, showed additive anti-proliferative effects in the BRAF mutant cell line Malme-3M. In summary, targeting CDK4 inhibits growth and induces apoptosis in melanoma cells in vitro, suggesting that CDK4 may be a rational therapeutic target for metastatic melanoma. PMID:26201960

  2. Brk/Protein tyrosine kinase 6 phosphorylates p27KIP1, regulating the activity of cyclin D-cyclin-dependent kinase 4.

    PubMed

    Patel, Priyank; Asbach, Benedikt; Shteyn, Elina; Gomez, Cindy; Coltoff, Alexander; Bhuyan, Sadia; Tyner, Angela L; Wagner, Ralf; Blain, Stacy W

    2015-05-01

    Cyclin D and cyclin-dependent kinase 4 (cdk4) are overexpressed in a variety of tumors, but their levels are not accurate indicators of oncogenic activity because an accessory factor such as p27(Kip1) is required to assemble this unstable dimer. Additionally, tyrosine (Y) phosphorylation of p27 (pY88) is required to activate cdk4, acting as an "on/off switch." We identified two SH3 recruitment domains within p27 that modulate pY88, thereby modulating cdk4 activity. Via an SH3-PXXP interaction screen, we identified Brk (breast tumor-related kinase) as a high-affinity p27 kinase. Modulation of Brk in breast cancer cells modulates pY88 and increases resistance to the cdk4 inhibitor PD 0332991. An alternatively spliced form of Brk (Alt Brk) which contains its SH3 domain blocks pY88 and acts as an endogenous cdk4 inhibitor, identifying a potentially targetable regulatory region within p27. Brk is overexpressed in 60% of breast carcinomas, suggesting that this facilitates cell cycle progression by modulating cdk4 through p27 Y phosphorylation. p27 has been considered a tumor suppressor, but our data strengthen the idea that it should also be considered an oncoprotein, responsible for cyclin D-cdk4 activity. PMID:25733683

  3. Effects of CDK4/6 Inhibition in Hormone Receptor-Positive/Human Epidermal Growth Factor Receptor 2-Negative Breast Cancer Cells with Acquired Resistance to Paclitaxel

    PubMed Central

    Trapé, Adriana Priscila; Liu, Shuying; Cortes, Andrea Carolina; Ueno, Naoto T.; Gonzalez-Angulo, Ana Maria

    2016-01-01

    Among patients with hormone receptor (HR)-positive breast cancer, those with residual disease after neoadjuvant chemotherapy have a higher risk of relapse and poorer survival than those with a complete response. Previous studies have revealed a correlation between activation of cell cycle-regulating pathways in HR-positive breast cancer, particularly cyclin-dependent kinase (CDK) 4 and 6/cyclin D1 signaling, and resistance to standard therapies. Although CDK4/6 inhibition by palbociclib in combination with endocrine therapy has shown potent antiproliferative effects in HR-positive/human epidermal growth factor receptor 2 (HER2)-negative breast cancer, the potential role of palbociclib in re-sensitizing chemotherapy-resistant HR-positive breast cancer is not well defined. We hypothesized that CDK4/6 inhibition by palbociclib re-sensitizes HR-positive/HER2-negative residual breast cancer to taxane-based adjuvant therapy. Using cell counting, flow cytometry, and western blotting, we evaluated the efficacy of palbociclib alone and in concurrent or sequential combination with paclitaxel in parental and paclitaxel-resistant T47D HR-positive/HER2-negative breast cancer cells. The CDK4/6 pathway was constitutively active in both parental and paclitaxel-resistant T47D cells; thus, both cell types were highly sensitive to the inhibitory effects of single-agent palbociclib on cell growth and cell cycle progression. However, palbociclib did not re-sensitize resistant cells to paclitaxel-induced G2/M arrest and cell death in any of the combinations tested. Our results suggest that CDK4/6 inhibition by palbociclib does not re-sensitize HR-positive/HER2-negative residual breast cancer to chemotherapy. Nevertheless, the fact that CDK4/6 activation remained intact in paclitaxel-resistant cells indicates that patients who have HR-positive/HER2-negative residual disease after taxane-based neoadjuvant chemotherapy may still benefit from palbociclib in combination with other regimens

  4. Atomic structure of Hsp90-Cdc37-Cdk4 reveals that Hsp90 traps and stabilizes an unfolded kinase.

    PubMed

    Verba, Kliment A; Wang, Ray Yu-Ruei; Arakawa, Akihiko; Liu, Yanxin; Shirouzu, Mikako; Yokoyama, Shigeyuki; Agard, David A

    2016-06-24

    The Hsp90 molecular chaperone and its Cdc37 cochaperone help stabilize and activate more than half of the human kinome. However, both the mechanism by which these chaperones assist their "client" kinases and the reason why some kinases are addicted to Hsp90 while closely related family members are independent are unknown. Our structural understanding of these interactions is lacking, as no full-length structures of human Hsp90, Cdc37, or either of these proteins with a kinase have been elucidated. Here we report a 3.9 angstrom cryo-electron microscopy structure of the Hsp90-Cdc37-Cdk4 kinase complex. Surprisingly, the two lobes of Cdk4 are completely separated with the β4-β5 sheet unfolded. Cdc37 mimics part of the kinase N lobe, stabilizing an open kinase conformation by wedging itself between the two lobes. Finally, Hsp90 clamps around the unfolded kinase β5 strand and interacts with exposed N- and C-lobe interfaces, protecting the kinase in a trapped unfolded state. On the basis of this structure and an extensive amount of previously collected data, we propose unifying conceptual and mechanistic models of chaperone-kinase interactions. PMID:27339980

  5. Real-time proliferation of porcine cumulus cells is related to the protein levels and cellular distribution of Cdk4 and Cx43.

    PubMed

    Kempisty, Bartosz; Ziółkowska, Agnieszka; Piotrowska, Hanna; Zawierucha, Piotr; Antosik, Paweł; Bukowska, Dorota; Ciesiółka, Sylwia; Jaśkowski, Jędrzej M; Brüssow, Klaus P; Nowicki, Michał; Zabel, Maciej

    2013-09-01

    The proper maturation of cumulus somatic cells depends on bidirectional communication between the oocyte and the surrounding cumulus cells (CCs). The aim of this study was (i) to investigate maturation markers, such as Cx43 and Cdk4 protein levels, and (ii) to analyze the distribution of these two proteins in CCs cultured for 44, 88, 132, and 164 hours in both separated and cumulus-enclosed oocyte cultures. CCs were isolated from porcine ovarian follicles after the treatment of the recovered COCs with collagenase. Then, the separated CCs were cultured in TCM-199 for 0 to 164 hours, using a real-time cellular analyzer; however, the immunostaining was performed only after 44, 88, and 132 hours. The protein levels and distribution were analyzed using confocal microscopy. After the CCs underwent in vitro cultivation (IVC) for 25 hours, a logarithmically increasing normalized proliferation index was found throughout the entire 164 hours cultivation time. The Cx43 and Cdk4 proteins were observed at higher levels after 44 hours of culture than before IVC. After 88 and 132 hours of IVC, no significant alterations in either mRNA or protein levels of Cx43 and Cdk4 were found. Cx43 and Cdk4 were localized in the cell nucleus before IVC, whereas after 44, 88, and 132 hours of IVC, both proteins translocated to the cytoplasm. In cumulus-enclosed oocyte cultures, Cdk4 was localized both in the nucleus and cytoplasm, whereas Cx43 was only in the cytoplasm. Additionally, only low levels of the cumulus expansion markers MIS and SNAT3 were observed. In summary, we could demonstrate that the in vitro cultivation of CCs was associated with cell proliferation and that Cx43 and Cdk4 gene expression was upregulated after IVC, resulting in significantly higher protein levels. Moreover, the two proteins translocated from the nucleus to the cytoplasm of the CCs during IVC. The protein distribution is presumably related to different protein functions during bidirectional communication via

  6. Analysis of Latvian familial melanoma patients shows novel variants in the noncoding regions of CDKN2A and that the CDK4 mutation R24H is a founder mutation.

    PubMed

    Veinalde, Rūta; Ozola, Aija; Azarjana, Kristīne; Molven, Anders; Akslen, Lars A; Doniņa, Simona; Proboka, Guna; Cēma, Ingrīda; Baginskis, Ainārs; Pjanova, Dace

    2013-06-01

    Hereditary cutaneous melanoma is associated with mutations in the high-risk CDKN2A gene in about 40% of melanoma-prone families. Mutations in the CDK4 gene are the cause in only a few pedigrees. In this study, we analyzed 20 Latvian familial melanoma probands and carried out a comprehensive analysis of CDKN2A including sequencing of its promoter/intronic regions and deletion screening. We also analyzed the critical second exon of the CDK4 gene. One novel intronic variant (IVS2+82C>T) of the CDKN2A gene and a small deletion (c.-20677_-20682delGTACGC) in its promoter region were found. Genotyping of the novel variants in larger melanoma and control groups indicated that the deletion increases the risk of melanoma (odds ratio=6.353, 95% confidence interval: 1.34-30.22, P=0.0168). The CDK4 gene analysis showed a Latvian melanoma family with the mutation R24H carried on the same haplotype as in two previously described Latvian CDK4-positive families. Our study suggests that the main risk gene in Latvian families with a strong family history of melanoma is CDK4 and that most of the other cases analyzed could be sporadic or associated with low-penetrance risk genes. PMID:23546221

  7. Histological Classification and Immunohistochemical Evaluation of MDM2 and CDK4 Expression in Canine Liposarcoma.

    PubMed

    Avallone, G; Roccabianca, P; Crippa, L; Lepri, E; Brunetti, B; Bernardini, C; Forni, M; Olandese, A; Sarli, G

    2016-07-01

    Canine liposarcoma is an uncommon soft tissue sarcoma usually arising in the subcutis. While liposarcoma classification in dogs is based solely on histology, in humans it depends on the detection of genetic abnormalities that can lead to specific protein overexpression. This study is an immunohistochemical evaluation of MDM2 and CDK4 expression in canine liposarcoma designed to assess the correlation of these proteins with histologic type, grade, mitotic index and Ki67 labeling index and evaluate their utility in improving tumor classification. Fifty-three liposarcomas were retrospectively collected: 24 were well differentiated liposarcomas (WDL), 16 of which expressed MDM2 and 21 CDK4; 7 were myxoid liposarcomas (ML), 1 of which expressed MDM2 and 5 expressed CDK4; 18 were pleomorphic liposarcomas (PL), all were MDM2 negative and 12 expressed CDK4. Four tumors were morphologically consistent with dedifferentiated liposarcoma (DDL) a subtype described only in humans: 3 expressed MDM2 and 4 expressed CDK4. MDM2 expression correlated with histotype (highly expressed in WDL and DDL) and grade (highly expressed in grade 1 tumors). Histotype correlated with the Ki67 labeling index (lowest in WDL and highest in DDL). A revised classification, considering MDM2 expression, allowed 8 WDL to be reclassified as PL and correlated significantly with mitotic and Ki67 labeling index (both significantly lower in WDL and progressively higher in ML and DDL). These results partially parallel data reported for human liposarcomas, suggesting that WDL and DDL are distinct neoplastic entities characterized by MDM2 expression, which may represent a useful diagnostic and potentially prognostic marker for canine liposarcoma. PMID:26993784

  8. miR-124 radiosensitizes human esophageal cancer cell TE-1 by targeting CDK4.

    PubMed

    Zhang, Y H; Wang, Q Q; Li, H; Ye, T; Gao, F; Liu, Y C

    2016-01-01

    Radiotherapy is one of the most important treatments for esophageal cancer, but radioresistance remains a major challenge. Previous studies have shown that microRNAs (miRNAs or miRs) are involved in human cancers. miR-124 has been widely reported in various cancers and it is intimately involved in proliferation, cell cycle regulation, apoptosis, migration, and invasion of cancer cells. The aim of this study was to explore the relationship between the miR-124/cyclin-dependent kinase 4 (CDK4) axis and the radiosensitivity of esophageal cancer cells. In this study, we identified the reduced expression of miR-124 in 18 paired esophageal cancer tissues compared to their matched normal tissues. In order to investigate the physiological role of miR-124 in esophageal cancer, the cell counting kit-8 (CCK-8) assay and wound healing assay were performed, and the results suggest that miR-124 overexpression decreases tumor growth and aggression. Next, we detected the effects of ectopic miR-124 expression on the apoptosis of an esophageal cancer cell line (TE-1) following radiotherapy. Using the CCK-8 assay and Hoechst 332528 stain, we found that ectopic expression of miR-124 led to a higher percentage of apoptotic cells. Finally, we identified that CDK4 is a direct target of miR-124 in TE-1 cells using target prediction algorithms and a luciferase reporter assay. Moreover, western blot assay confirmed that CDK4 was downregulated during miR-124 transfection. Taken together, we illustrate that the miR-124/CDK4 axis plays an important role in radiation sensitivity of human esophageal cancer cells by targeting CDK4. PMID:27323123

  9. Analysing the Effect of Mutation on Protein Function and Discovering Potential Inhibitors of CDK4: Molecular Modelling and Dynamics Studies.

    PubMed

    N, Nagasundaram; Zhu, Hailong; Liu, Jiming; V, Karthick; C, George Priya Doss; Chakraborty, Chiranjib; Chen, Luonan

    2015-01-01

    The cyclin-dependent kinase 4 (CDK4)-cyclin D1 complex plays a crucial role in the transition from the G1 phase to S phase of the cell cycle. Among the CDKs, CDK4 is one of the genes most frequently affected by somatic genetic variations that are associated with various forms of cancer. Thus, because the abnormal function of the CDK4-cyclin D1 protein complex might play a vital role in causing cancer, CDK4 can be considered a genetically validated therapeutic target. In this study, we used a systematic, integrated computational approach to identify deleterious nsSNPs and predict their effects on protein-protein (CDK4-cyclin D1) and protein-ligand (CDK4-flavopiridol) interactions. This analysis resulted in the identification of possible inhibitors of mutant CDK4 proteins that bind the conformations induced by deleterious nsSNPs. Using computational prediction methods, we identified five nsSNPs as highly deleterious: R24C, Y180H, A205T, R210P, and R246C. From molecular docking and molecular dynamic studies, we observed that these deleterious nsSNPs affected CDK4-cyclin D1 and CDK4-flavopiridol interactions. Furthermore, in a virtual screening approach, the drug 5_7_DIHYDROXY_ 2_ (3_4_5_TRI HYDROXYPHENYL) _4H_CHROMEN_ 4_ONE displayed good binding affinity for proteins with the mutations R24C or R246C, the drug diosmin displayed good binding affinity for the protein with the mutation Y180H, and the drug rutin displayed good binding affinity for proteins with the mutations A205T and R210P. Overall, this computational investigation of the CDK4 gene highlights the link between genetic variation and biological phenomena in human cancer and aids in the discovery of molecularly targeted therapies for personalized treatment. PMID:26252490

  10. Cigarette smoke extract alters the cell cycle via the phospholipid transfer protein/transforming growth factor-β1/CyclinD1/CDK4 pathway.

    PubMed

    Chai, Xue-Min; Li, You-Lun; Chen, Hong; Guo, Shu-Liang; Shui, Li-Li; Chen, Ya-Juan

    2016-09-01

    This study was aimed to investigate the effect of phospholipid transfer protein (PLTP) on cigarette smoke extract (CSE)-induced alteration of the cell cycle and the possible mechanism. Male Wistar rats and the rat alveolar epithelial cell line (RLE-6TN) were exposed to normal air or different concentrations of CSE. Then PLTP siRNA was transfected into cells and an inhibitor of transforming growth factor-β1 (TGF-β1) was administered prior to CSE exposure. Histological changes and cell cycle stage were recorded, as were the expression levels of PLTP, TGF-β1, CyclinD1 and CDK4. Resulting morphological changes included diffuse interstitial substance incrassation and elevated alveolar rupturing. Flow cytometry analysis revealed an increase in the number of cells in the G1 phase in a time- and dose-related manner. Both PLTP and TGF-β1 were up-regulated at protein and mRNA levels, whereas CyclinD1 and CDK4 expression was down-regulated after CSE exposure. Furthermore, PLTP siRNA significantly suppressed CSE-induced TGF-β1 expression, resulting in up-regulation of CyclinD1 and CDK4, but the TGF-β1 inhibitor was not able to abrogate CSE-induced PLTP over-expression. In conclusion, PLTP may operate upstream of the TGF-β1/CyclinD1/CDK4 pathway and may mediate the CSE-induced G1 arrest in RLE-6TN cells. Our work provides some new insight into the relation between PLTP and cell cycle progression. PMID:27260126

  11. 1α,25 dihydroxi-vitamin D{sub 3} modulates CDK4 and CDK6 expression and localization

    SciTech Connect

    Irazoqui, Ana P.; Heim, Nadia B.; Boland, Ricardo L.; Buitrago, Claudia G.

    2015-03-27

    We recently reported that the vitamin D receptor (VDR) and p38 MAPK participate in pro-differentiation events triggered by 1α,25(OH){sub 2}-vitamin D{sub 3} [1,25D] in skeletal muscle cells. Specifically, our studies demonstrated that 1,25D promotes G0/G1 arrest of cells inducing cyclin D3 and cyclin dependent kinases inhibitors (CKIs) p21{sup Waf1/Cip1} and p27{sup Kip1} expression in a VDR and p38 MAPK dependent manner. In this work we present data indicating that cyclin-dependent kinases (CDKs) 4 and 6 also play a role in the mechanism by which 1,25D stimulates myogenesis. To investigate VDR involvement in hormone regulation of CDKs 4 and 6, we significantly reduced its expression by the use of a shRNA against mouse VDR, generating the skeletal muscle cell line C2C12-VDR. Investigation of changes in cellular cycle regulating proteins by immunoblotting showed that the VDR is involved in the 1,25D –induced CDKs 4 and 6 protein levels at 6 h of hormone treatment. CDK4 levels remains high during S phase peak and G0/G1 arrest while CDK6 expression decreases at 12 h and increases again al 24 h. The up-regulation of CDKs 4 and 6 by 1,25D (6 h) was abolished in C2C12 cells pre-treated with the ERK1/2 inhibitor, UO126. Moreover, CDKs 4 and 6 expression induced by the hormone nor was detected when α and β isoforms of p38 MAPK were inhibited by compound SB203580. Confocal images show that there is not co-localization between VDR and CDKs at 6 h of hormone treatment, however CDK4 and VDR co-localizates in nucleus after 12 h of 1,25D exposure. Of relevance, at this time 1,25D promotes CDK6 localization in a peri-nuclear ring. Our data demonstrate that the VDR, ERK1/2 and p38 MAPK are involved in the control of CDKs 4 and 6 by 1,25D in skeletal muscle cells sustaining the operation of a VDR and MAPKs –dependent mechanism in hormone modulation of myogenesis. - Highlights: • 1,25D modulates CDKs 4 and 6 expression in skeletal muscle cells. • CDK4 co

  12. p18 inhibits reprogramming through inactivation of Cdk4/6

    PubMed Central

    Zhu, Shaohua; Cao, Jiani; Sun, Hongyan; Liu, Kun; Li, Yaqiong; Zhao, Tongbiao

    2016-01-01

    Pluripotent stem cells (PSCs), including embryonic and induced pluripotent stem cells (iPSCs), show atypical cell cycle regulation characterized by a high proliferation rate and a shorter G1 phase compared with somatic cells. The mechanisms by which somatic cells remodel their cell cycle to achieve the high proliferation rate of PSCs during reprogramming are unclear. Here we identify that the Ink4 protein p18, which is expressed at high levels in somatic cells but at low levels in PSCs, is a roadblock to successful reprogramming. Mild inhibition of p18 expression enhances reprogramming efficiency, while ectopic expression of p18 completely blocks reprogramming. Mechanistic studies show that expression of wild-type p18, but not a p18D68N mutant which cannot inhibit Cdk4/6, down-regulates expression of Cdk4/6 target genes involved in DNA synthesis (TK, TS, DHFR, PCNA) and cell cycle regulation (CDK1 and CCNA2) and thus inhibits reprogramming. These results indicate that p18 blocks reprogramming by targeting Cdk4/6-mediated cell cycle regulation. Taken together, our results define a novel pathway that inhibits somatic cell reprogramming, and provide a new target to enhance reprogramming efficiency. PMID:27484146

  13. 3D-QSAR and 3D-QSSR studies of thieno[2,3-d]pyrimidin-4-yl hydrazone analogues as CDK4 inhibitors by CoMFA analysis

    PubMed Central

    Cai, Bao-qin; Jin, Hai-xiao; Yan, Xiao-jun; Zhu, Peng; Hu, Gui-xiang

    2014-01-01

    Aim: To investigate the structural basis underlying potency and selectivity of a series of novel analogues of thieno[2,3-d]pyrimidin-4-yl hydrazones as cyclin-dependent kinase 4 (CDK4) inhibitors and to use this information for drug design strategies. Methods: Three-dimensional quantitative structure-activity relationship (3D-QSAR) and three-dimensional quantitative structure-selectivity relationship (3D-QSSR) models using comparative molecular field analysis (CoMFA) were conducted on a training set of 48 compounds. Partial least squares (PLS) analysis was employed. External validation was performed with a test set of 9 compounds. Results: The obtained 3D-QSAR model (q2=0.724, r2=0.965, r2pred=0.945) and 3D-QSSR model (q2=0.742, r2=0.923, r2pred=0.863) were robust and predictive. Contour maps with good compatibility to active binding sites provided insight into the potentially important structural features required to enhance activity and selectivity. The contour maps indicated that bulky groups at R1 position could potentially enhance CDK4 inhibitory activity, whereas bulky groups at R3 position have the opposite effect. Appropriate incorporation of bulky electropositive groups at R4 position is favorable and could improve both potency and selectivity to CDK4. Conclusion: These two models provide useful information to guide drug design strategies aimed at obtaining potent and selective CDK4 inhibitors. PMID:24122012

  14. Dual Inhibition of CDK4/Rb and PI3K/AKT/mTOR Pathways by ON123300 Induces Synthetic Lethality in Mantle Cell Lymphomas

    PubMed Central

    Divakar, Saikrishna A.; Reddy, M.V. Ramana; Cosenza, Stephen C.; Baker, Stacey J.; Perumal, Deepak; Antonelli, Anthony C.; Brody, Joshua; Akula, Balaiah; Parekh, Samir; Reddy, E. Premkumar

    2015-01-01

    This study describes the characterization of a novel kinase inhibitor, ON123300, which inhibits CDK4/6 and PI3K-δ and exhibits potent activity against mantle cell lymphomas (MCLs) both in vitro and in vivo. We examined the effects of PD0332991 and ON 123300 on cell cycle progression, modulation of the Rb and PI3K/AKT pathways, and the induction of apoptosis in MCL cell lines and patient-derived samples. When Granta 519 and Z138C cells were incubated with PD0332991 and ON123300, both compounds were equally efficient in their ability to inhibit the phosphorylation of Rb family proteins. However, only ON123300 inhibited the phosphorylation of proteins associated with the PI3K/AKT pathway. Cells treated with PD0332991 rapidly accumulated in the G0/G1 phase of cell cycle as a function of increasing concentration. Although ON123300-treated cells arrested similarly at lower concentrations, higher concentrations resulted in the induction of apoptosis, which was not observed in PD 0332991-treated samples. Mouse xenograft assays also showed a strong inhibition of MCL tumor growth in ON123300-treated animals. Finally, treatment of ibrutinib-sensitive and resistant patient-derived MCLs with ON123300 also triggered apoptosis and inhibition of the Rb and PI3K/AKT pathways, suggesting that this compound might be an effective agent in MCL, including ibrutinib-resistant forms of the disease. PMID:26174628

  15. Determining the effect of transforming growth factor-β1 on cdk4 and p27 in gastric cancer and cholangiocarcinoma.

    PubMed

    Lee, Sung Ryol; Shin, Jae Wook; Kim, Hyung Ook; Son, Byung Ho; Yoo, Chang Hak; Shin, Jun Ho

    2013-02-01

    Gastric cancer and cholangiocarcinoma are problematic throughout the world due to their destructive malignancy. In attempts to treat cholangiocarcinoma and gastric cancer, researchers often explore the effects of transforming growth factor-β1 (TGF-β1). TGF-β1 plays a crucial role in causing cell cycle arrest and fibrosis in cancer cells. The present study aimed to identify whether TGF-β1 is capable of functioning as an antitumor agent in two cancer cell lines; cholangiocarcinoma and gastric cancer. The downregulation of cyclin dependent kinase (cdk) 4 and the upregulation of p27 were investigated, in order to identify possible antitumor functions of TGF-β1. A number of different methods were implemented, including cell proliferation assay, bicinchoninic acid (BCA) assay and western blot analysis with TGF-β1, AGS (human gastric cancer cell line) and SUN-1196 (human cholangiocarcinoma cell line). In the AGS study, cdk4 values decreased from 1.000 to 0.670 and then to 0.664, with increasing TGF-β1 concentrations of 0, 0.5 and 5 ng/ml, respectively. By contrast, p27 values increased from 1.000 to 1.391 and then to 1.505, with increasing TGF-β1 concentrations of 0, 0.5 and 5 ng/ml, respectively. In the SUN-1196 study, p27 values increased from 0.548 to 0.807 and then to 0.844 with increasing TGF-β1 concentrations of 5, 25 and 50 ng/ml, respectively. Certain concentrations of TGF-β1 play antitumor roles in gastric cancer through the down-regulation of cdk4 and upregulation of p27. Certain TGF-β1 concentrations also have antitumor roles in cholangiocarcinoma through the upregulation of p27. With these results, we came a step closer to finding a cure for cholangiocarcinoma and gastric cancer. PMID:23420090

  16. Determining the effect of transforming growth factor-β1 on cdk4 and p27 in gastric cancer and cholangiocarcinoma

    PubMed Central

    LEE, SUNG RYOL; SHIN, JAE WOOK; KIM, HYUNG OOK; SON, BYUNG HO; YOO, CHANG HAK; SHIN, JUN HO

    2013-01-01

    Gastric cancer and cholangiocarcinoma are problematic throughout the world due to their destructive malignancy. In attempts to treat cholangiocarcinoma and gastric cancer, researchers often explore the effects of transforming growth factor-β1 (TGF-β1). TGF-β1 plays a crucial role in causing cell cycle arrest and fibrosis in cancer cells. The present study aimed to identify whether TGF-β1 is capable of functioning as an antitumor agent in two cancer cell lines; cholangiocarcinoma and gastric cancer. The downregulation of cyclin dependent kinase (cdk) 4 and the upregulation of p27 were investigated, in order to identify possible antitumor functions of TGF-β1. A number of different methods were implemented, including cell proliferation assay, bicinchoninic acid (BCA) assay and western blot analysis with TGF-β1, AGS (human gastric cancer cell line) and SUN-1196 (human cholangiocarcinoma cell line). In the AGS study, cdk4 values decreased from 1.000 to 0.670 and then to 0.664, with increasing TGF-β1 concentrations of 0, 0.5 and 5 ng/ml, respectively. By contrast, p27 values increased from 1.000 to 1.391 and then to 1.505, with increasing TGF-β1 concentrations of 0, 0.5 and 5 ng/ml, respectively. In the SUN-1196 study, p27 values increased from 0.548 to 0.807 and then to 0.844 with increasing TGF-β1 concentrations of 5, 25 and 50 ng/ml, respectively. Certain concentrations of TGF-β1 play antitumor roles in gastric cancer through the down-regulation of cdk4 and upregulation of p27. Certain TGF-β1 concentrations also have antitumor roles in cholangiocarcinoma through the upregulation of p27. With these results, we came a step closer to finding a cure for cholangiocarcinoma and gastric cancer. PMID:23420090

  17. Short-term cultivation of porcine cumulus cells influences the cyclin-dependent kinase 4 (Cdk4) and connexin 43 (Cx43) protein expression--a real-time cell proliferation approach.

    PubMed

    Kempisty, Bartosz; Ziółkowska, Agnieszka; Piotrowska, Hanna; Ciesiółka, Sylwia; Antosik, Paweł; Bukowska, Dorota; Zawierucha, Piotr; Woźna, Magdalena; Jaśkowski, Jędrzej M; Brüssow, Klaus P; Nowicki, Michał; Zabel, Maciej

    2013-01-01

    The CC (cumulus cell) proliferation index in relation to the expression and distribution of Cdk4 and Cx43 proteins, which are crucial factors for oocyte maturation, was investigated. Cumulus-oocyte complexes (COCs) were recovered from pubertal crossbred Landrace gilts and treated with collagenase, and separated CCs were cultured in standard TCM199 medium for 44 h. At each step of in vitro cultivation (IVC) of CCs (0, 12, 24 and 44 h), a normalized proliferation index was assessed. Cdk4 and Cx43 protein expression and the CC-specific cellular distribution were analyzed by confocal microscopic observation. The normalized proliferation index (number of cells attached, measured by impedance) was increased in the first 12 h of IVC (P<0.01) and differed between 12 h and 24 h of cultivation (P<0.001). Later, between 24 h-44 h of IVC, the CC proliferation rate was stable, and no significant differences were observed. Based on the confocal microscopic observation, increased expression of both Cdk4 and Cx43 was found after 44 h of IVC compared with the expression of these proteins before IVC. Moreover, after IVC, a substantial translocation of Cdk4 and Cx43 was noted from the nucleus to the cytoplasm of CCs. In conclusion, it was demonstrated for the first time that CCs can be cultured in vitro separately without oocytes and that the proliferation index was significantly increased in the first 12 h of IVC, which may reflect the process of ordinary cumulus cell expansion. Furthermore, the expression of both Cdk4 and Cx43 in CCs suggested that these proteins may be regarded as markers not only of proper oocyte maturation but also of CC differentiation. Translocation of these proteins into the cytoplasm of CCs after 44 h of IVC may be related to the expansion process. PMID:23685568

  18. Short-term Cultivation of Porcine Cumulus Cells Influences the Cyclin-dependent Kinase 4 (Cdk4) and Connexin 43 (Cx43) Protein Expression—A Real-time Cell Proliferation Approach

    PubMed Central

    KEMPISTY, Bartosz; ZIÓŁKOWSKA, Agnieszka; PIOTROWSKA, Hanna; CIESIÓŁKA, Sylwia; ANTOSIK, Paweł; BUKOWSKA, Dorota; ZAWIERUCHA, Piotr; WOŹNA, Magdalena; JAŚKOWSKI, Jędrzej M.; BRÜSSOW, Klaus P.; NOWICKI, Michał; ZABEL, Maciej

    2013-01-01

    Abstract The CC (cumulus cell) proliferation index in relation to the expression and distribution of Cdk4 and Cx43 proteins, which are crucial factors for oocyte maturation, was investigated. Cumulus-oocyte complexes (COCs) were recovered from pubertal crossbred Landrace gilts and treated with collagenase, and separated CCs were cultured in standard TCM199 medium for 44 h. At each step of in vitro cultivation (IVC) of CCs (0, 12, 24 and 44 h), a normalized proliferation index was assessed. Cdk4 and Cx43 protein expression and the CC-specific cellular distribution were analyzed by confocal microscopic observation. The normalized proliferation index (number of cells attached, measured by impedance) was increased in the first 12 h of IVC (P<0.01) and differed between 12 h and 24 h of cultivation (P<0.001). Later, between 24 h–44 h of IVC, the CC proliferation rate was stable, and no significant differences were observed. Based on the confocal microscopic observation, increased expression of both Cdk4 and Cx43 was found after 44 h of IVC compared with the expression of these proteins before IVC. Moreover, after IVC, a substantial translocation of Cdk4 and Cx43 was noted from the nucleus to the cytoplasm of CCs. In conclusion, it was demonstrated for the first time that CCs can be cultured in vitro separately without oocytes and that the proliferation index was significantly increased in the first 12 h of IVC, which may reflect the process of ordinary cumulus cell expansion. Furthermore, the expression of both Cdk4 and Cx43 in CCs suggested that these proteins may be regarded as markers not only of proper oocyte maturation but also of CC differentiation. Translocation of these proteins into the cytoplasm of CCs after 44 h of IVC may be related to the expansion process. PMID:23685568

  19. piR-651 promotes tumor formation in non-small cell lung carcinoma through the upregulation of cyclin D1 and CDK4.

    PubMed

    Li, Dan; Luo, Yingquan; Gao, Yawen; Yang, Yue; Wang, Yina; Xu, Yan; Tan, Shengyu; Zhang, Yuwei; Duan, Juan; Yang, Yu

    2016-09-01

    Piwi-interacting RNAs (piRNAs or piRs) are a novel class of non-coding RNAs that participate in germline development by silencing transposable elements and regulating gene expression. To date, the association between piRNAs and non‑small cell lung carcinoma (NSCLC) has not yet been elucidated. In the present study, we have demonstrated that a significant increase in piR-651 expression occurs in NSCLC. Furthermore, the abnormal expression of piR-651 was associated with cancer progression in the patients with NSCLC. The upregulation of piR-651 in A549 cells caused a significant increase in cell viability and metastasis. The percentage of arrested cells in the G0/G1 phase was lower after piR-651 overexpression compared with the controls. We also examined the expression of oncogenes and cancer suppressor genes following piR-651 overexpression in NSCLC cells. Only the expression levels of cyclin D1 and CDK4 significantly correlated with piR-651 expression both in vivo and in vitro. Furthermore, by injecting nude mice with A549 cells transfected with piR-651 plasmids to establish a xenograft model, we demonstrated that there was a correlation between piR-651 overexpression and tumor growth, which was mediated by cyclin D1 and CDK4. These findings strongly support the notion that piR-651 induces NSCLC progression through the cyclin D1 and CDK4 pathway and it may have applications as a potential diagnostic indicator and therapeutic target in the management of NSCLC. PMID:27431575

  20. CDK4/6 Inhibitor PD0332991 in Glioblastoma Treatment: Does It Have a Future?

    PubMed Central

    Schröder, Lisette B. W.; McDonald, Kerrie L.

    2015-01-01

    Glioblastoma is aggressive, highly infiltrating, and the most frequent malignant form of brain cancer. With a median survival time of only 14.6 months, when treated with the standard of care, it is essential to find new therapeutic options. A specific CDK4/6 inhibitor, PD0332991, obtained accelerated approval from the Food and Drug Administration for the treatment of patients with advanced estrogen receptor-positive and HER2-negative breast cancer. Common alterations in the cyclin D1-cyclin-dependent kinase 4/6-retinoblastoma 1 pathway in glioblastoma make PD0332991 also an interesting drug for the treatment of glioblastoma. Promising results in in vitro studies, where patient derived glioblastoma cell lines showed sensitivity to PD0332991, gave motive to start in vivo studies. Outcomes of these studies have been contrasting in terms of PD0332991 efficacy within the brain: more research is necessary to conclude whether CDK4/6 inhibitor can be beneficial in the treatment of glioblastoma. PMID:26649278

  1. Cdk4 and Nek2 Signal Binucleation and Centrosome Amplification in a Her2+ Breast Cancer Model

    PubMed Central

    Harrison Pitner, Mary Kathryn; Saavedra, Harold I.

    2013-01-01

    Centrosome amplification (CA) is a contributor to carcinogenesis, generating aneuploidy, and chromosome instability. Previous work shows that breast adenocarcinomas have a higher frequency of centrosome defects compared to normal breast tissues. Abnormal centrosome phenotypes are found in pre-malignant lesions, suggesting an early role in breast carcinogenesis. However, the role of CA in breast cancers remains elusive. Identification of pathways and regulatory molecules involved in the generation of CA is essential to understanding its role in breast tumorigenesis. We established a breast cancer model of CA using Her2-positive cells. Our goal was to identify centrosome cycle molecules that are deregulated by aberrant Her2 signaling and the mechanisms driving CA. Our results show some Her2+ breast cancer cell lines harbor both CA and binucleation. Abolishing the expression of Cdk4 abrogated both CA and binucleation in these cells. We also found the source of binucleation in these cells to be defective cytokinesis that is normalized by downregulation of Cdk4. Protein levels of Nek2 diminish upon Cdk4 knockdown and vice versa, suggesting a molecular connection between Cdk4 and Nek2. Knockdown of Nek2 reduces CA and binucleation in this model while its overexpression further enhances centrosome amplification. We conclude that CA is modulated through Cdk4 and Nek2 signaling and that binucleation is a likely source of CA in Her2+ breast cancer cells. PMID:23776583

  2. Association of CDK4 germline and BRAF somatic mutations in a patient with multiple primary melanomas and BRAF inhibitor resistance.

    PubMed

    Governa, Maurizio; Caprarella, Evelina; Dalla Pozza, Edoardo; Vigato, Enrico; Maritan, Monia; Caputo, Glenda G; Zannoni, Marina; Rosina, Paolo; Elefanti, Lisa; Stagni, Camilla; Menin, Chiara

    2015-10-01

    Many genetic alterations, including predisposing or somatic mutations, may contribute toward the development of melanoma. Although CDKN2A and CDK4 are high-penetrance genes for melanoma, MC1R is a low-penetrance gene that has been associated most consistently with the disease. Moreover, BRAF is the most frequently somatically altered oncogene and is a validated therapeutic target in melanoma. This paper reports a case of multiple primary melanoma with germline CDK4 mutation, MC1R variant, and somatic BRAF mutation in nine out of 10 melanomas, indicating that a common pathogenesis, because of a predisposing genetic background, may be shared among distinct subsequent melanomas of probable clonal origin. After 3 months of targeted therapy with BRAF inhibitor, our patient developed resistance with rapid progression of the disease leading to death. This is the first case in which early resistance to BRAF inhibitor has been reported in a patient with CDK4 germline mutation. PMID:26110554

  3. Synthetic Lethal Therapy for KRAS Mutant Non-small-cell Lung Carcinoma with Nanoparticle-mediated CDK4 siRNA Delivery

    PubMed Central

    Mao, Cheng-Qiong; Xiong, Meng-Hua; Liu, Yang; Shen, Song; Du, Xiao-Jiao; Yang, Xian-Zhu; Dou, Shuang; Zhang, Pei-Zhuo; Wang, Jun

    2014-01-01

    The KRAS mutation is present in ~20% of lung cancers and has not yet been effectively targeted for therapy. This mutation is associated with a poor prognosis in non-small-cell lung carcinomas (NSCLCs) and confers resistance to standard anticancer treatment drugs, including epidermal growth factor receptor tyrosine kinase inhibitors. In this study, we exploited a new therapeutic strategy based on the synthetic lethal interaction between cyclin-dependent kinase 4 (CDK4) downregulation and the KRAS mutation to deliver micellar nanoparticles (MNPs) containing small interfering RNA targeting CDK4 (MNPsiCDK4) for treatment in NSCLCs harboring the oncogenic KRAS mutation. Following MNPsiCDK4 administration, CDK4 expression was decreased, accompanied by inhibited cell proliferation, specifically in KRAS mutant NSCLCs. However, this intervention was harmless to normal KRAS wild-type cells, confirming the proposed mechanism of synthetic lethality. Moreover, systemic delivery of MNPsiCDK4 significantly inhibited tumor growth in an A549 NSCLC xenograft murine model, with depressed expression of CDK4 and mutational KRAS status, suggesting the therapeutic promise of MNPsiCDK4 delivery in KRAS mutant NSCLCs via a synthetic lethal interaction between KRAS and CDK4. PMID:24496383

  4. Marine steroids as potential anticancer drug candidates: In silico investigation in search of inhibitors of Bcl-2 and CDK-4/Cyclin D1.

    PubMed

    Saikia, Surovi; Kolita, Bhaskor; Dutta, Partha P; Dutta, Deep J; Neipihoi; Nath, Shyamalendu; Bordoloi, Manobjyoti; Quan, Pham Minh; Thuy, Tran Thu; Phuong, Doan Lan; Long, Pham Quoc

    2015-10-01

    Star fishes (Asteroidea) are rich in polar steroids with diverse structural characteristics. The structural modifications of star fish steroids occur at 3β, 4β, 5α, 6α (or β), 7α (or β), 8, 15α (or β) and 16β positions of the steroidal nucleus and in the side chain. Widely found polar steroids in starfishes include polyhydroxysteroids, steroidal sulfates, glycosides, steroid oligoglycosides etc. Bioactivity of these steroids is less studied; only a few reports like antibacterial, cytotoxic activity etc. are available. In continuation of our search for bioactive molecules from natural sources, we undertook in silico screening of steroids from star fishes against Bcl-2 and CDK-4/Cyclin D1 - two important targets of progression and proliferation of cancer cells. We have screened 182 natural steroids from star fishes occurring in different parts of the world and their 282 soft-derivatives by in silico methods. Their physico-chemical properties, drug-likeliness, binding potential with the selected targets, ADMET (absorption, distribution, metabolism, toxicity) were predicted. Further, the results were compared with those of existing steroidal and non steroidal drugs and inhibitors of Bcl-2 and CDK-4/Cyclin D1. The results are promising and unveil that some of these steroids can be potent leads for cancer treatments. PMID:26111591

  5. Autochthonous primary and metastatic melanomas in Hgf-Cdk4 R24C mice evade T-cell-mediated immune surveillance.

    PubMed

    Landsberg, Jennifer; Gaffal, Evelyn; Cron, Mira; Kohlmeyer, Judith; Renn, Marcel; Tüting, Thomas

    2010-10-01

    Genetically engineered mouse models offer new opportunities to investigate the role of cell-mediated immunity in the natural progression of melanoma in an immunocompetent host. Here we report that Hgf-Cdk4(R24C) mice spontaneously develop a spectrum of primary melanomas with high penetrance during their first year of life. Malignant transformation proceeds in a stepwise manner from multiple melanocytic nevi to single nodular melanomas and disseminated metastases in most mice. Migrating melanoma cells invade the draining lymph nodes without activating the immune system. Autochthonous primary tumors are destroyed following experimental introduction of immune surveillance using an adoptive lymphocyte transfer approach. However, some tumor cells are able to survive, evade immune cell control, and recur both locally and systemically. Immune tolerance in recurring tumors may be supported by immunosuppressive Gr1(+) myeloid cells. Taken together, our results demonstrate that primary and metastatic melanomas developing spontaneously in Hgf-Cdk4(R24C) mice effectively evade cellular immune surveillance. PMID:20649939

  6. Dual inhibition of CDK4/Rb and PI3K/AKT/mTOR pathways by ON123300 induces synthetic lethality in mantle cell lymphomas.

    PubMed

    Divakar, S K A; Ramana Reddy, M V; Cosenza, S C; Baker, S J; Perumal, D; Antonelli, A C; Brody, J; Akula, B; Parekh, S; Reddy, E Premkumar

    2016-01-01

    This study describes the characterization of a novel kinase inhibitor, ON123300, which inhibits CDK4/6 (cyclin-dependent kinases 4 and 6) and phosphatidylinositol 3 kinase-δ (PI3K-δ) and exhibits potent activity against mantle cell lymphomas (MCLs) both in vitro and in vivo. We examined the effects of PD0332991 and ON123300 on cell cycle progression, modulation of the retinoblastoma (Rb) and PI3K/AKT pathways, and the induction of apoptosis in MCL cell lines and patient-derived samples. When Granta 519 and Z138C cells were incubated with PD0332991 and ON123300, both compounds were equally efficient in their ability to inhibit the phosphorylation of Rb family proteins. However, only ON123300 inhibited the phosphorylation of proteins associated with the PI3K/AKT pathway. Cells treated with PD0332991 rapidly accumulated in the G0/G1 phase of cell cycle as a function of increasing concentration. Although ON123300-treated cells arrested similarly at lower concentrations, higher concentrations resulted in the induction of apoptosis, which was not observed in PD0332991-treated samples. Mouse xenograft assays also showed a strong inhibition of MCL tumor growth in ON123300-treated animals. Finally, treatment of ibrutinib-sensitive and -resistant patient-derived MCLs with ON123300 also triggered apoptosis and inhibition of the Rb and PI3K/AKT pathways, suggesting that this compound might be an effective agent in MCL, including ibrutinib-resistant forms of the disease. PMID:26174628

  7. CCND1–CDK4–mediated cell cycle progression provides a competitive advantage for human hematopoietic stem cells in vivo

    PubMed Central

    Mende, Nicole; Kuchen, Erika E.; Lesche, Mathias; Grinenko, Tatyana; Kokkaliaris, Konstantinos D.; Hanenberg, Helmut; Lindemann, Dirk; Dahl, Andreas; Platz, Alexander; Höfer, Thomas; Calegari, Federico

    2015-01-01

    Maintenance of stem cell properties is associated with reduced proliferation. However, in mouse hematopoietic stem cells (HSCs), loss of quiescence results in a wide range of phenotypes, ranging from functional failure to extensive self-renewal. It remains unknown whether the function of human HSCs is controlled by the kinetics of cell cycle progression. Using human HSCs and human progenitor cells (HSPCs), we report here that elevated levels of CCND1–CDK4 complexes promoted the transit from G0 to G1 and shortened the G1 cell cycle phase, resulting in protection from differentiation-inducing signals in vitro and increasing human leukocyte engraftment in vivo. Further, CCND1–CDK4 overexpression conferred a competitive advantage without impacting HSPC numbers. In contrast, accelerated cell cycle progression mediated by elevated levels of CCNE1–CDK2 led to the loss of functional HSPCs in vivo. Collectively, these data suggest that the transition kinetics through the early cell cycle phases are key regulators of human HSPC function and important for lifelong hematopoiesis. PMID:26150472

  8. Cell Cycle Regulating Kinase Cdk4 as a Potential Target for Tumor Cell Treatment and Tumor Imaging

    PubMed Central

    Graf, Franziska; Koehler, Lena; Kniess, Torsten; Wuest, Frank; Mosch, Birgit; Pietzsch, Jens

    2009-01-01

    The cyclin-dependent kinase (Cdk)-cyclin D/retinoblastoma (pRb)/E2F cascade, which controls the G1/S transition of cell cycle, has been found to be altered in many neoplasias. Inhibition of this pathway by using, for example, selective Cdk4 inhibitors has been suggested to be a promising approach for cancer therapy. We hypothesized that appropriately radiolabeled Cdk4 inhibitors are suitable probes for tumor imaging and may be helpful studying cell proliferation processes in vivo by positron emission tomography. Herein, we report the synthesis and biological, biochemical, and radiopharmacological characterizations of two 124I-labeled small molecule Cdk4 inhibitors (8-cyclopentyl-6-iodo-5-methyl-2-(4-piperazin-1-yl-phenylamino)-8H-pyrido[2,3-d]-pyrimidin-7-one (CKIA) and 8-cyclopentyl-6-iodo-5-methyl-2-(5-(piperazin-1-yl)-pyridin-2-yl-amino)-8H-pyrido[2,3-d]pyrimidin-7-one (CKIB)). Our data demonstrate a defined and specific inhibition of tumor cell proliferation through CKIA and CKIB by inhibition of the Cdk4/pRb/E2F pathway emphasizing potential therapeutic benefit of CKIA and CKIB. Furthermore, radiopharmacological properties of [124I]CKIA and [124I]CKIB observed in human tumor cells are promising prerequisites for in vivo biodistribution and imaging studies. PMID:19551155

  9. CDKN2A and CDK4 variants in Latvian melanoma patients: analysis of a clinic-based population.

    PubMed

    Pjanova, Dace; Engele, Ludmila; Randerson-Moor, Juliette A; Harland, Mark; Bishop, D Timothy; Newton Bishop, Julia A; Taylor, Claire; Debniak, Tadeusz; Lubinski, Jan; Kleina, Regina; Heisele, Olita

    2007-06-01

    Germline mutations of the CDKN2A and CDK4 genes explain a significant proportion of familial melanoma. To date, there have been few published estimations of the prevalence of such mutations in sporadic melanoma patients. In this study, we investigated CDKN2A and CDK4 exon 2 for germline mutations in 125 consecutive cutaneous malignant melanoma patients recruited through the Latvian Oncological Center, using amplicon melting analysis and sequencing. No disease-related CDKN2A germline mutations were identified in any of the melanoma patients analysed but the previously described CDK4 mutation, Arg24His, was found in one patient with a family history of melanoma. CDKN2A polymorphisms were studied as putative low penetrance susceptibility genes. The proportion of cases with polymorphisms in this Latvian melanoma population was Ala148Thr (c.442G>A) (6%), 500 C/G (c.*29C>G) (18%), and 540 C/T (c.*69C>T) (20%); however, only the frequency of the Ala148Thr polymorphism was higher in melanoma patients than in 203 controls (6 versus 1%, P=0.03). Ala148Thr has also been reported in association with melanoma in a Polish series but not in an English series. We therefore examined the Ala148Thr carrier's haplotype in 10 Latvian and 39 Polish samples. No significant difference was seen between these populations and the predominant haplotype observed in English samples, giving no indication that the discrepancy could be explained by population differences in linkage disequilibrium. In summary, our results show that germline mutations at the CDKN2A locus are rare in sporadic melanoma in Latvia. The study does, however, provide some additional evidence for a role for the CDKN2A polymorphism Ala148Thr as a low penetrance susceptibility gene. The detected CDK4 exon 2 mutation was found in only the seventh family identified worldwide with a germline CDK4 mutation. PMID:17505264

  10. Antitumour potential of BPT: a dual inhibitor of cdk4 and tubulin polymerization.

    PubMed

    Mahale, S; Bharate, S B; Manda, S; Joshi, P; Jenkins, P R; Vishwakarma, R A; Chaudhuri, B

    2015-01-01

    The marine natural product fascaplysin (1) is a potent Cdk4 (cyclin-dependent kinase 4)-specific inhibitor, but is toxic to all cell types possibly because of its DNA-intercalating properties. Through the design and synthesis of numerous fascaplysin analogues, we intended to identify inhibitors of cancer cell growth with good therapeutic window with respect to normal cells. Among various non-planar tryptoline analogues prepared, N-(biphenyl-2-yl) tryptoline (BPT, 6) was identified as a potent inhibitor of cancer cell growth and free from DNA-binding properties owing to its non-planar structure. This compound was tested in over 60 protein kinase assays. It displayed inhibition of Cdk4-cyclin D1 enzyme in vitro far more potently than many other kinases including Cdk family members. Although it blocks growth of cancer cells deficient in the mitotic-spindle checkpoint at the G0/G1 phase of the cell cycle, the block occurs primarily at the G2/M phase. BPT inhibits tubulin polymerization in vitro and acts as an enhancer of tubulin depolymerization of paclitaxel-stabilized tubulin in live cells. Western blot analyses indicated that, in p53-positive cells, BPT upregulates the expression of p53, p21 and p27 proteins, whereas it downregulates the expression of cyclin B1 and Cdk1. BPT selectively kills SV40-transformed mouse embryonic hepatic cells and human fibroblasts rather than untransformed cells. BPT inhibited the growth of several human cancer cells with an IC50<1 μM. The pharmacokinetic study in BALB/c mice indicated good plasma exposure after intravenous administration. It was found to be efficacious at 1/10th the maximum-tolerated dose (1000 mg/kg) against human tumours derived from HCT-116 (colon) and NCI-H460 (lung) cells in SCID (severe-combined immunodeficient) mice models. BPT is a relatively better anticancer agent than fascaplysin with an unusual ability to block two overlapping yet crucial phases of the cell cycle, mitosis and G0/G1. Its ability to

  11. Antitumour potential of BPT: a dual inhibitor of cdk4 and tubulin polymerization

    PubMed Central

    Mahale, S; Bharate, S B; Manda, S; Joshi, P; Jenkins, P R; Vishwakarma, R A; Chaudhuri, B

    2015-01-01

    The marine natural product fascaplysin (1) is a potent Cdk4 (cyclin-dependent kinase 4)-specific inhibitor, but is toxic to all cell types possibly because of its DNA-intercalating properties. Through the design and synthesis of numerous fascaplysin analogues, we intended to identify inhibitors of cancer cell growth with good therapeutic window with respect to normal cells. Among various non-planar tryptoline analogues prepared, N-(biphenyl-2-yl) tryptoline (BPT, 6) was identified as a potent inhibitor of cancer cell growth and free from DNA-binding properties owing to its non-planar structure. This compound was tested in over 60 protein kinase assays. It displayed inhibition of Cdk4-cyclin D1 enzyme in vitro far more potently than many other kinases including Cdk family members. Although it blocks growth of cancer cells deficient in the mitotic-spindle checkpoint at the G0/G1 phase of the cell cycle, the block occurs primarily at the G2/M phase. BPT inhibits tubulin polymerization in vitro and acts as an enhancer of tubulin depolymerization of paclitaxel-stabilized tubulin in live cells. Western blot analyses indicated that, in p53-positive cells, BPT upregulates the expression of p53, p21 and p27 proteins, whereas it downregulates the expression of cyclin B1 and Cdk1. BPT selectively kills SV40-transformed mouse embryonic hepatic cells and human fibroblasts rather than untransformed cells. BPT inhibited the growth of several human cancer cells with an IC50 <1 μM. The pharmacokinetic study in BALB/c mice indicated good plasma exposure after intravenous administration. It was found to be efficacious at 1/10th the maximum-tolerated dose (1000 mg/kg) against human tumours derived from HCT-116 (colon) and NCI-H460 (lung) cells in SCID (severe-combined immunodeficient) mice models. BPT is a relatively better anticancer agent than fascaplysin with an unusual ability to block two overlapping yet crucial phases of the cell cycle, mitosis and G0/G1. Its ability to

  12. miR-1 suppresses the growth of esophageal squamous cell carcinoma in vivo and in vitro through the downregulation of MET, cyclin D1 and CDK4 expression

    PubMed Central

    JIANG, SEN; ZHAO, CHAO; YANG, XIAODI; LI, XIANGYANG; PAN, QING; HUANG, HAIJIN; WEN, XUYANG; SHAN, HUSHENG; LI, QIANWEN; DU, YUNXIANG; ZHAO, YAPING

    2016-01-01

    Several aberrant microRNAs (miRNAs or miRs) have been implicated in esophageal cancer (EC), which is widely prevalent in China. However, their role in EC tumorigenesis has not yet been fully elucidated. In the present study, we determined that miR-1 was downregulated in esophageal squamous cell carcinoma (ESCC) tissues compared with adjacent non-neoplastic tissues using RT-qPCR, and confirmed this using an ESCC cell line. Using a nude mouse xenograft model, we confirmed that the re-expression of miR-1 significantly inhibited ESCC tumor growth. A tetrazolium assay and a trypan blue exclusion assay revealed that miR-1 suppressed ESCC cell proliferation and increased apoptosis, whereas the silencing of miR-1 promoted cell proliferation and decreased apoptosis, suggesting that miR-1 is a novel tumor suppressor. To elucidate the molecular mechanisms of action of miR-1 in ESCC, we investigated putative targets using bioinformatics tools. MET, cyclin D1 and cyclin-dependent kinase 4 (CDK4), which are involved in the hepatocyte growth factor (HGF)/MET signaling pathway, were found to be targets of miR-1. miR-1 expression inversely correlated with MET, cyclin D1 and CDK4 expression in ESCC cells. miR-1 directly targeted MET, cyclin D1 and CDK4, suppressing ESCC cell growth. The newly identified miR-1/MET/cyclin D1/CDK4 axis provides new insight into the molecular mechanisms of ESCC pathogenesis and indicates a novel strategy for the diagnosis and treatment of ESCC. PMID:27247259

  13. miR-1 suppresses the growth of esophageal squamous cell carcinoma in vivo and in vitro through the downregulation of MET, cyclin D1 and CDK4 expression.

    PubMed

    Jiang, Sen; Zhao, Chao; Yang, Xiaodi; Li, Xiangyang; Pan, Qing; Huang, Haijin; Wen, Xuyang; Shan, Husheng; Li, Qianwen; Du, Yunxiang; Zhao, Yaping

    2016-07-01

    Several aberrant microRNAs (miRNAs or miRs) have been implicated in esophageal cancer (EC), which is widely prevalent in China. However, their role in EC tumorigenesis has not yet been fully elucidated. In the present study, we determined that miR‑1 was downregulated in esophageal squamous cell carcinoma (ESCC) tissues compared with adjacent non-neoplastic tissues using RT-qPCR, and confirmed this using an ESCC cell line. Using a nude mouse xenograft model, we confirmed that the re-expression of miR‑1 significantly inhibited ESCC tumor growth. A tetrazolium assay and a trypan blue exclusion assay revealed that miR‑1 suppressed ESCC cell proliferation and increased apoptosis, whereas the silencing of miR‑1 promoted cell proliferation and decreased apoptosis, suggesting that miR‑1 is a novel tumor suppressor. To elucidate the molecular mechanisms of action of miR‑1 in ESCC, we investigated putative targets using bioinformatics tools. MET, cyclin D1 and cyclin-dependent kinase 4 (CDK4), which are involved in the hepatocyte growth factor (HGF)/MET signaling pathway, were found to be targets of miR‑1. miR‑1 expression inversely correlated with MET, cyclin D1 and CDK4 expression in ESCC cells. miR‑1 directly targeted MET, cyclin D1 and CDK4, suppressing ESCC cell growth. The newly identified miR‑1/MET/cyclin D1/CDK4 axis provides new insight into the molecular mechanisms of ESCC pathogenesis and indicates a novel strategy for the diagnosis and treatment of ESCC. PMID:27247259

  14. Population-based prevalence of CDKN2A and CDK4 mutations in patients with multiple primary melanomas.

    PubMed

    Helsing, Per; Nymoen, Dag Andre; Ariansen, Sarah; Steine, Solrun J; Maehle, Lovise; Aamdal, Steinar; Langmark, Frøydis; Loeb, Mitchell; Akslen, Lars A; Molven, Anders; Andresen, Per Arne

    2008-02-01

    The presence of multiple primary cutaneous melanomas (MPM) has been advocated as guidance to identifying melanoma families. Frequencies of CDKN2A mutations in materials of sporadic MPM cases from pigmented lesion clinics vary between 8 and 15%. Patients with MPM have therefore been regarded as good candidates for CDKN2A mutational screening. We describe a population-based study where all persons in Norway diagnosed with MPM between 1953 and 2004 (n = 738 alive per April 2004) were invited to participate. Three-hundred-and-ninety patients (52.8%) responded confidentially. Mutations in CDKN2A were found in 6.9% of the respondents. Eighty-one MPM patients (20.8%) reported that they belonged to melanoma families, and 17 (21.0%) of these harboured a CDKN2A mutation, compared to 3.2% of the nonfamilial cases. The probability of finding a CDKN2A mutation increased when the patients had three or more melanomas, or a young age of onset of first melanoma. We identified five novel CDKN2A variants (Ala57Gly, Pro81Arg, Ala118Val, Leu130Val, and Arg131Pro) and four that previously have been reported in melanoma families (Glu27X, Met53Ile, Arg87Trp, and Ala127Pro). A large deletion (g.13623_23772del10150) encompassing exon 1alpha and the 5' part of exon 2 was detected in six patients with a family history of melanoma. Three patients, belonging to the same family, had the CDK4 Arg24His mutation. The frequency of CDKN2A mutations was lower than previously reported in other studies, an observation which probably is due to the population-based design of our study. PMID:18023021

  15. Involvement of PSMD10, CDK4, and Tumor Suppressors in Development of Intrahepatic Cholangiocarcinoma of Syrian Golden Hamsters Induced by Clonorchis sinensis and N-Nitrosodimethylamine

    PubMed Central

    Uddin, Md. Hafiz; Choi, Min-Ho; Kim, Woo Ho; Jang, Ja-June; Hong, Sung-Tae

    2015-01-01

    Background Clonorchis sinensis is a group-I bio-carcinogen for cholangiocarcinoma (CCA). Although the epidemiological evidence links clonorchiasis and CCA, the underlying molecular mechanism involved in this process is poorly understood. In the present study, we investigated expression of oncogenes and tumor suppressors, including PSMD10, CDK4, p53 and RB in C. sinensis induced hamster CCA model. Methods Different histochemical/immunohistochemical techniques were performed to detect CCA in 4 groups of hamsters: uninfected control (Ctrl.), infected with C. sinensis (Cs), ingested N-nitrosodimethylamine (NDMA), and both Cs infected and NDMA introduced (Cs+NDMA). The liver tissues from all groups were analyzed for gene/protein expressions by quantitative PCR (qPCR) and western blotting. Principal Findings CCA was observed in all hamsters of Cs+NDMA group with well, moderate, and poorly differentiated types measured in 21.8% ± 1.5%, 13.3% ± 1.3%, and 10.8% ± 1.3% of total tissue section areas respectively. All CCA differentiations progressed in a time dependent manner, starting from the 8th week of infection. CCA stroma was characterized with increased collagen type I, mucin, and proliferative cell nuclear antigen (PCNA). The qPCR analysis showed PSMD10, CDK4 and p16INK4 were over-expressed, whereas p53 was under-expressed in the Cs+NDMA group. We observed no change in RB1 at mRNA level but found significant down-regulation of RB protein. The apoptosis related genes, BAX and caspase 9 were found downregulated in the CCA tissue. Gene/protein expressions were matched well with the pathological changes of different groups except the NDMA group. Though the hamsters in the NDMA group showed no marked pathological lesions, we observed over-expression of Akt/PKB and p53 genes proposing molecular interplay in this group which might be related to the CCA initiation in this animal model. Conclusions/Significance The present findings suggest that oncogenes, PSMD10 and CDK4

  16. MicroRNA-206 induces G1 arrest in melanoma by inhibition of CDK4 and Cyclin D.

    PubMed

    Georgantas, Robert W; Streicher, Katie; Luo, Xiaobing; Greenlees, Lydia; Zhu, Wei; Liu, Zheng; Brohawn, Philip; Morehouse, Christopher; Higgs, Brandon W; Richman, Laura; Jallal, Bahija; Yao, Yihong; Ranade, Koustubh

    2014-03-01

    Expression profiling of microRNAs in melanoma lesional skin biopsies compared with normal donor skin biopsies, as well as melanoma cell lines compared with normal melanocytes, revealed that hsa-miR-206 was down-regulated in melanoma (-75.4-fold, P = 1.7 × 10(-4)). MiR-206 has been implicated in a large number of cancers, including breast, lung, colorectal, ovarian, and prostate cancers; however, its role in tumor development remains largely unknown, its biologic function is poorly characterized, and its targets affecting cancer cells are largely unknown. MiR-206 reduced growth and migration/invasion of multiple melanoma cell lines. Bioinformatics identified cell cycle genes CDK2, CDK4, Cyclin C, and Cyclin D1 as strong candidate targets. Western blots and 3'UTR reporter gene assays revealed that miR-206 inhibited translation of CDK4, Cyclin D1, and Cyclin C. Additionally, hsa-miR-206 transfection induced G1 arrest in multiple melanoma cell lines. These observations support hsa-miR-206 as a tumor suppressor in melanoma and identify Cyclin C, Cyclin D1, and CDK4 as miR-206 targets. PMID:24289491

  17. A mutant allele of BARA/LIN-9 rescues the cdk4 {sup -/-} phenotype by releasing the repression on E2F-regulated genes

    SciTech Connect

    Sandoval, Raudel; Xue Jiaping; Tian Xinyong; Barrett, Kelly; Pilkinton, Mark; Ucker, David S.; Raychaudhuri, Pradip; Kineman, Rhonda D.; Luque, Raul M.; Baida, Gleb; Zou, Xianghong; Kiyokawa, Hiroaki; Valli, V.E.; Cook, James L.; Colamonici, Oscar R. . E-mail: ocolamon@uic.edu

    2006-08-01

    It has been proposed that C. elegans LIN-9 functions downstream of CDK4 in a pathway that regulates cell proliferation. Here, we report that mammalian BARA/LIN-9 is a predominantly nuclear protein that inhibits cell proliferation. More importantly, we demonstrate that BARA/LIN-9 also acts downstream of cyclin D/CDK4 in mammalian cells since (i) its antiproliferative effect is partially blocked by coexpression of cyclin D1, and (ii) a mutant form that lacks the first 84 amino acids rescues several phenotypic alterations observed in mice null for cdk4. Interestingly, mutation of BARA/LIN-9 restores the expression of E2F target genes in CDK4 null MEFs, indicating that the wild-type protein plays a role in the expression of genes required for the G1/S transition.

  18. Functional, chemical genomic, and super-enhancer screening identify sensitivity to cyclin D1/CDK4 pathway inhibition in Ewing sarcoma

    PubMed Central

    Crompton, Brian; Cowley, Glenn; Vazquez, Francisca; Weir, Barbara A.; Tsherniak, Aviad; Parasuraman, Sudha; Kim, Sunkyu; Alexe, Gabriela; Stegmaier, Kimberly

    2015-01-01

    Ewing sarcoma is an aggressive bone and soft tissue tumor in children and adolescents, with treatment remaining a clinical challenge. This disease is mediated by somatic chromosomal translocations of the EWS gene and a gene encoding an ETS transcription factor, most commonly, FLI1. While direct targeting of aberrant transcription factors remains a pharmacological challenge, identification of dependencies incurred by EWS/FLI1 expression would offer a new therapeutic avenue. We used a combination of super-enhancer profiling, near-whole genome shRNA-based and small-molecule screening to identify cyclin D1 and CDK4 as Ewing sarcoma-selective dependencies. We revealed that super-enhancers mark Ewing sarcoma specific expression signatures and EWS/FLI1 target genes in human Ewing sarcoma cell lines. Particularly, a super-enhancer regulates cyclin D1 and promotes its expression in Ewing sarcoma. We demonstrated that Ewing sarcoma cells require CDK4 and cyclin D1 for survival and anchorage-independent growth. Additionally, pharmacologic inhibition of CDK4 with selective CDK4/6 inhibitors led to cytostasis and cell death of Ewing sarcoma cell lines in vitro and growth delay in an in vivo Ewing sarcoma xenograft model. These results demonstrated a dependency in Ewing sarcoma on CDK4 and cyclin D1 and support exploration of CDK4/6 inhibitors as a therapeutic approach for patients with this disease. PMID:26337082

  19. Establishment of clonal myogenic cell lines from severely affected dystrophic muscles - CDK4 maintains the myogenic population

    PubMed Central

    2011-01-01

    Background A hallmark of muscular dystrophies is the replacement of muscle by connective tissue. Muscle biopsies from patients severely affected with facioscapulohumeral muscular dystrophy (FSHD) may contain few myogenic cells. Because the chromosomal contraction at 4q35 linked to FSHD is thought to cause a defect within myogenic cells, it is important to study this particular cell type, rather than the fibroblasts and adipocytes of the endomysial fibrosis, to understand the mechanism leading to myopathy. Results We present a protocol to establish clonal myogenic cell lines from even severely dystrophic muscle that has been replaced mostly by fat, using overexpression of CDK4 and the catalytic component of telomerase (human telomerase reverse transcriptase; hTERT), and a subsequent cloning step. hTERT is necessary to compensate for telomere loss during in vitro cultivation, while CDK4 prevents a telomere-independent growth arrest affecting CD56+ myogenic cells, but not their CD56- counterpart, in vitro. Conclusions These immortal cell lines are valuable tools to reproducibly study the effect of the FSHD mutation within myoblasts isolated from muscles that have been severely affected by the disease, without the confounding influence of variable amounts of contaminating connective-tissue cells. PMID:21798090

  20. Genomic rearrangements of the CDKN2A locus are infrequent in Italian malignant melanoma families without evidence of CDKN2A/CDK4 point mutations.

    PubMed

    Vignoli, Marina; Scaini, Maria Chiara; Ghiorzo, Paola; Sestini, Roberta; Bruno, William; Menin, Chiara; Gensini, Francesca; Piazzini, Mauro; Testori, Alessandro; Manoukian, Siranoush; Orlando, Claudio; D'Andrea, Emma; Bianchi-Scarrà, Giovanna; Genuardi, Maurizio

    2008-12-01

    Predisposition to familial cutaneous malignant melanoma has been associated with mutations in the CDKN2A and CDK4 genes. However, only a small subgroup of melanoma pedigrees harbour CDKN2A or CDK4 germline mutations. It is possible that other types of CDKN2A rearrangements, not detectable by routine PCR-based approaches, are involved in a fraction of melanoma cases negative for point sequence changes. In order to gain insights on the possible role of CDKN2A large deletions or duplications in melanoma susceptibility in the Italian population, we screened a series of 124 cutaneous malignant melanoma families referred to five national medical/cancer genetics centres. All probands were negative for point mutations in CDKN2A and CDK4. All samples were tested by MLPA (multiplex ligation-dependent probe amplification), and the results were confirmed by real-time quantitative PCR in a subset of 53 cases. No genomic rearrangements were detected in this series, one of the largest so far investigated. These data suggest that large deletions/duplications in the CDKN2A locus are infrequently involved in the development of familial melanoma in the Italian population. Based on these results, routine search for these rearrangements in CDKN2A- and CDK4-mutation negative melanoma families is not warranted, although it would be reasonable to pursue it in selected cases with very strong family history and/or showing linkage to 9p21. PMID:19011513

  1. Assessing and Increasing Physical Activity

    ERIC Educational Resources Information Center

    Van Camp, Carole M.; Hayes, Lynda B.

    2012-01-01

    Increasing physical activity is a crucial component of any comprehensive approach to combat the growing obesity epidemic. This review summarizes recent behavioral research on the measurement of physical activity and interventions aimed at increasing physical activity and provides directions for future research.

  2. Epac1 knockdown inhibits the proliferation of ovarian cancer cells by inactivating AKT/Cyclin D1/CDK4 pathway in vitro and in vivo.

    PubMed

    Gao, Meng; Ma, Yanyan; Bast, Robert C; Li, Yue; Wan, Lu; Liu, Yanping; Sun, Yingshuo; Fang, Zhenghui; Zhang, Lining; Wang, Xiaoyan; Wei, Zengtao

    2016-07-01

    Ovarian cancer is the leading cause of death among gynecological malignancies, and high grade serous ovarian carcinoma is the most common and most aggressive subtype. Recently, it was demonstrated that cAMP mediates protein kinase A-independent effects through Epac (exchange protein directly activated by cAMP) proteins. Epac proteins, including Epac1 and Epac2, are implicated in several diverse cellular responses, such as insulin secretion, exocytosis, cellular calcium handling and formation of cell-cell junctions. Several reports document that Epac1 could play vital roles in promoting proliferation, invasion and migration of some cancer cells. However, the expression levels and roles of Epac1 in ovarian cancer have not been investigated. In the present study, we detected the expression levels of Epac1 mRNA and protein in three kinds of ovarian cancer cells SKOV3, OVCAR3 and CAOV3. Furthermore, the effect of Epac1 knockdown on the proliferation and apoptosis of SKOV3 and OVCAR3 cells was evaluated in vitro and in vivo. The results showed that there was higher expression of Epac1 mRNA and protein in SKOV3 and OVCAR3 cells. Epac1 knockdown inhibited the proliferation of SKOV3 and OVCAR3 cells in vitro and in vivo. Decreased proliferation may be due to downregulation of Epac1-induced G1 phase arrest by inactivating the AKT/Cyclin D1/CDK4 pathway, but not to alterations in the MAPK pathway or to apoptosis. Taken together, our data provide new insight into the essential role of Epac1 in regulating growth of ovarian cancer cells and suggest that Epac1 might represent an attractive therapeutic target for treatment of ovarian cancer. PMID:27277757

  3. A fine structure genomic map of the region of 12q13 containing SAS and CDK4

    SciTech Connect

    Linder, C.Y.; Elkahloun, A.G.; Su, Y.A.

    1994-09-01

    We have recently adapted a method, originally described by Rackwitz, to the rapid restriction mapping of multiple cosmid DNA samples. Linearization of the cosmids at the lambda cohesive site using lambda terminase is followed by partial digestion with selected restriction enzymes and hybridization to oligonucleotides specific for the right or left hand termini. Partial digestions are performed in a microtiter plate thus allowing up to 12 cosmid clones to be digested with one restriction enzyme. We have applied this rapid restriction mapping method to cosmids derived from a region of chromosome 12q13 that has recently been shown to be amplified in a variety of cancers including malignant fibrous histiocytoma, fibrosarcoma, liposarcoma, osteosarcoma and brain tumors. A small segment of this amplification unit containing three genes, SAS (a membrane protein), CDK4 (a cyclin dependent kinase) and OS-9 (a recently described cDNA) has been analyzed with the system described above. This fine structure genomic map will be useful for completing the expression map of this region as well as characterizing its pattern of amplification in tumor specimens.

  4. Chemistry and biology of fascaplysin, a potent marine-derived CDK-4 inhibitor.

    PubMed

    Bharate, S B; Manda, S; Mupparapu, N; Battini, N; Vishwakarma, R A

    2012-06-01

    Marine natural products offer an abundant source of pharmacologically active agents with great diversity and complexity, and the potential to produce valuable therapeutic entities. Indole alkaloids is one of the important class of marine-derived secondary metabolites, with wide occurrence amongst variety of marine sources such as sponges, tunicates, algae, worms and microorganisms and have been extensively studied for their biological activities. Among this chemical family, a sponge-derived bis-indole alkaloid fascaplysin (1) exhibited broad range of bioactivities including antibacterial, antifungal, antiviral, anti-HIV-1-RTase, p56 tyrosine kinase inhibition, antimalarial, anti-angiogenic, antiproliferative activity against numerous cancer cell lines, specific inhibition of cyclin-dependent kinase-4 (IC(50) 350 nM) and action as a DNA intercalator. In the present review, the chemical diversity of natural as well as synthetic analogues of fascaplysin has been reviewed with a detailed account on synthetic reports and pharmacological studies. Our analysis of the structure-activity relationships of this family of compounds highlights the existence of various potential leads for the development of novel anticancer agents. PMID:22512549

  5. Increased Spreading Activation in Depression

    ERIC Educational Resources Information Center

    Foster, Paul S.; Yung, Raegan C.; Branch, Kaylei K.; Stringer, Kristi; Ferguson, Brad J.; Sullivan, William; Drago, Valeria

    2011-01-01

    The dopaminergic system is implicated in depressive disorders and research has also shown that dopamine constricts lexical/semantic networks by reducing spreading activation. Hence, depression, which is linked to reductions of dopamine, may be associated with increased spreading activation. However, research has generally found no effects of…

  6. A flexible multiplex bead-based assay for detecting germline CDKN2A and CDK4 variants in melanoma-prone kindreds.

    PubMed

    Lang, Julie M; Shennan, Michael; Njauw, Jenny C-N; Luo, Su; Bishop, Julia N; Harland, Mark; Hayward, Nicholas K; Tucker, Margaret A; Goldstein, Alisa M; Landi, Maria T; Puig, Susana; Gruis, Nelleke A; Bergman, Wilma; Bianchi-Scarra, Giovanna; Ghiorzo, Paola; Hogg, David; Tsao, Hensin

    2011-02-01

    The presence of recurrent high-risk mutations in cyclin-dependent kinase inhibitor 2A/cyclin-dependent kinase 4 (CDKN2A/CDK4) among melanoma-prone families suggests that a high-throughput, multiplex assay could serve as an effective initial screening tool. To this end, we have developed a multiplex bead-based assay for high-throughput CDKN2A/CDK4 genotyping in the context of familial melanoma. Genomic DNA from 1,603 subjects (1,005 in training set and 598 in validation set) were amplified by multiplex PCR using five CDKN2A/CDK4 primer sets followed by multiplex allele-specific primer extension for 39 distinct germline variants. The products were then sorted and analyzed using the Luminex xMAP system. Genotypes were compared with previously determined sequence data. In the Toronto training cohort, all 145 samples with known variants were detected by the bead assay (100% concordance). Analysis of the 598 samples from the GenoMEL validation set led to identification of 150/155 expected variants (96.77%). Overall, the bead assay correctly genotyped 1,540/1,603 (96.07%) of all individuals in the study and 1,540/1,545 (99.68%) of individuals whose variants were represented in the probe set. Out of a total of 62,517 allelic calls, 62,512 (99.99%) were correctly assigned. The multiplex bead-based assay is an accurate method for genotyping CDKN2A/CDK4 variants and is potentially useful in genotyping low-to-moderate melanoma risk single-nucleotide polymorphisms. PMID:21085193

  7. FLT3 and CDK4/6 inhibitors: signaling mechanisms and tumor burden in subcutaneous and orthotopic mouse models of acute myeloid leukemia.

    PubMed

    Zhang, Yaping; Hsu, Cheng-Pang; Lu, Jian-Feng; Kuchimanchi, Mita; Sun, Yu-Nien; Ma, Ji; Xu, Guifen; Zhang, Yilong; Xu, Yang; Weidner, Margaret; Huard, Justin; D'Argenio, David Z

    2014-12-01

    FLT3(ITD) subtype acute myeloid leukemia (AML) has a poor prognosis with currently available therapies. A number of small molecule inhibitors of FLT3 and/or CDK4/6 are currently under development. A more complete and quantitative understanding of the mechanisms of action of FLT3 and CDK4/6 inhibitors may better inform the development of current and future compounds that act on one or both of the molecular targets, and thus may lead to improved treatments for AML. In this study, we investigated in both subcutaneous and orthotopic AML mouse models, the mechanisms of action of three FLT3 and/or CDK4/6 inhibitors: AMG925 (Amgen), sorafenib (Bayer and Onyx), and quizartinib (Ambit Biosciences). A composite model was developed to integrate the plasma pharmacokinetics of these three compounds on their respective molecular targets, the coupling between the target pathways, as well as the resulting effects on tumor burden reduction in the subcutaneous xenograft model. A sequential modeling approach was used, wherein model structures and estimated parameters from upstream processes (e.g. PK, cellular signaling) were fixed for modeling subsequent downstream processes (cellular signaling, tumor burden). Pooled data analysis was employed for the plasma PK and cellular signaling modeling, while population modeling was applied to the tumor burden modeling. The resulting model allows the decomposition of the relative contributions of FLT3(ITD) and CDK4/6 inhibition on downstream signaling and tumor burden. In addition, the action of AMG925 on cellular signaling and tumor burden was further studied in an orthotopic tumor mouse model more closely representing the physiologically relevant environment for AML. PMID:25326874

  8. Prevalence of Germline BAP1, CDKN2A, and CDK4 Mutations in an Australian Population-Based Sample of Cutaneous Melanoma Cases.

    PubMed

    Aoude, Lauren G; Gartside, Michael; Johansson, Peter; Palmer, Jane M; Symmons, Judith; Martin, Nicholas G; Montgomery, Grant W; Hayward, Nicholas K

    2015-04-01

    Mutations in Cyclin-Dependent Kinase Inhibitor 2A (CDKN2A) and Cyclin-Dependent Kinase 4 (CDK4) contribute to susceptibility in approximately 40% of high-density cutaneous melanoma (CMM) families and about 2% of unselected CMM cases. BRCA-1 associated protein-1 (BAP1) has been more recently shown to predispose to CMM and uveal melanoma (UMM) in some families; however, its contribution to CMM development in the general population is unreported. We sought to determine the contribution of these genes to CMM susceptibility in a population-based sample of cases from Australia. We genotyped 1,109 probands from Queensland families and found that approximately 1.31% harbored mutations in CDKN2A, including some with novel missense mutations (p.R22W, p.G35R and p.I49F). BAP1 missense variants occurred in 0.63% of cases but no CDK4 variants were observed in the sample. This is the first estimate of the contribution of BAP1 and CDK4 to a population-based sample of CMM and supports the previously reported estimate of CDKN2A germline mutation prevalence. PMID:25787093

  9. Cdk5-mediated inhibition of APC/C-Cdh1 switches on the cyclin D1-Cdk4-pRb pathway causing aberrant S-phase entry of postmitotic neurons

    PubMed Central

    Veas-Pérez de Tudela, Miguel; Maestre, Carolina; Delgado-Esteban, María; Bolaños, Juan P.; Almeida, Angeles

    2015-01-01

    The anaphase-promoting complex/cyclosome (APC/C) is an E3 ubiquitin ligase that regulates cell cycle progression in proliferating cells. To enter the S-phase, APC/C must be inactivated by phosphorylation of its cofactor, Cdh1. In post-mitotic cells such as neurons APC/C-Cdh1 complex is highly active and responsible for the continuous degradation of mitotic cyclins. However, the specific molecular pathway that determines neuronal cell cycle blockade in post-mitotic neurons is unknown. Here, we show that activation of glutamatergic receptors in rat cortical primary neurons endogenously triggers cyclin-dependent kinase-5 (Cdk5)-mediated phosphorylation of Cdh1 leading to its cytoplasmic accumulation and disassembly from the APC3 core protein, causing APC/C inactivation. Conversely, pharmacological or genetic inhibition of Cdk5 promotes Cdh1 ubiquitination and proteasomal degradation. Furthermore, we show that Cdk5-mediated phosphorylation and inactivation of Cdh1 leads to p27 depletion, which switches on the cyclin D1-cyclin-dependent kinase-4 (Cdk4)-retinoblastoma protein (pRb) pathway to allow the S-phase entry of neurons. However, neurons do not proceed through the cell cycle and die by apoptosis. These results indicate that APC/C-Cdh1 actively suppresses an aberrant cell cycle entry and death of neurons, highlighting its critical function in neuroprotection. PMID:26658992

  10. Loss of CDKN2A expression is a frequent event in primary invasive melanoma and correlates with sensitivity to the CDK4/6 inhibitor PD0332991 in melanoma cell lines.

    PubMed

    Young, Richard J; Waldeck, Kelly; Martin, Claire; Foo, Jung H; Cameron, Donald P; Kirby, Laura; Do, Hongdo; Mitchell, Catherine; Cullinane, Carleen; Liu, Wendy; Fox, Stephen B; Dutton-Regester, Ken; Hayward, Nicholas K; Jene, Nicholas; Dobrovic, Alexander; Pearson, Richard B; Christensen, James G; Randolph, Sophia; McArthur, Grant A; Sheppard, Karen E

    2014-07-01

    We have investigated the potential for the p16-cyclin D-CDK4/6-retinoblastoma protein pathway to be exploited as a therapeutic target in melanoma. In a cohort of 143 patients with primary invasive melanoma, we used fluorescence in situ hybridization to detect gene copy number variations (CNVs) in CDK4, CCND1, and CDKN2A and immunohistochemistry to determine protein expression. CNVs were common in melanoma, with gain of CDK4 or CCND1 in 37 and 18% of cases, respectively, and hemizygous or homozygous loss of CDKN2A in 56%. Three-quarters of all patients demonstrated a CNV in at least one of the three genes. The combination of CCND1 gain with either a gain of CDK4 and/or loss of CDKN2A was associated with poorer melanoma-specific survival. In 47 melanoma cell lines homozygous loss, methylation or mutation of CDKN2A gene or loss of protein (p16(INK) (4A) ) predicted sensitivity to the CDK4/6 inhibitor PD0332991, while RB1 loss predicted resistance. PMID:24495407

  11. Classroom Activities: Increase the Challenge.

    ERIC Educational Resources Information Center

    Cote-Moran, Claudette

    Four classroom activities for second language learning are described. They include games and other exercises designed to enhance vocabulary development, review grammatical structures, encourage conversation on a variety of topics, and introduce cultural elements into instruction. All use materials that are readily available, and all are intended…

  12. Increasing Youth Physical Activity with Activity Calendars

    ERIC Educational Resources Information Center

    Eckler, Seth

    2016-01-01

    Physical educators often struggle with ways to get their students to be active beyond the school day. One strategy to accomplish this is the use of physical activity calendars (PACs). The purpose of this article is to support the use of PACs and give practical advice for creating effective PACs.

  13. The effect of telomerase template antagonist GRN163L on bone-marrow-derived rat mesenchymal stem cells is reversible and associated with altered expression of cyclin d1, cdk4 and cdk6.

    PubMed

    Tokcaer-Keskin, Zeynep; Dikmen, Zeliha G; Ayaloglu-Butun, Fatma; Gultekin, Sinan; Gryaznov, Sergei M; Akcali, Kamil Can

    2010-06-01

    Telomerase activity is essential for the continued growth and survival of malignant cells, therefore inhibition of this activity presents an attractive target for anti-cancer therapy. The telomerase inhibitor GRN163L, was shown to inhibit the growth of cancer cells both in vitro and in vivo. Mesenchymal stem cells (MSCs) also show telomerase activity in maintaining their self-renewal; therefore the effects of telomerase inhibitors on MSCs may be an issue of concern. MSCs are multipotent cells and are important for the homeostasis of the organism. In this study, we sought to demonstrate in vitro effects of GRN163L on rat MSCs. When MSCs were treated with 1 microM GRN163L, their phenotype changed from spindle-shaped cells to rounded ones and detached from the plate surface, similar to cancer cells. Quantitative-RT-PCR and immunoblotting results revealed that GRN163L holds MSCs at the G1 state of the cell cycle, with a drastic decrease in mRNA and protein levels of cyclin D1 and its cdk counterparts, cdk4 and cdk6. This effect was not observed when MSCs were treated with a mismatch control oligonucleotide. One week after GRN163L was removed, mRNA and protein expressions of the genes, as well as the phenotype of MSCs returned to those of untreated cells. Therefore, we concluded that GRN163L does not interfere with the self-renewal and differentiation of MSCs under short term in vitro culture conditions. Our study provides additional support for treating cancers by administrating GRN163L without depleting the body's stem cell pools. PMID:20180048

  14. Preclinical Characterization of G1T28: A Novel CDK4/6 Inhibitor for Reduction of Chemotherapy-Induced Myelosuppression.

    PubMed

    Bisi, John E; Sorrentino, Jessica A; Roberts, Patrick J; Tavares, Francis X; Strum, Jay C

    2016-05-01

    Chemotherapy-induced myelosuppression continues to represent the major dose-limiting toxicity of cytotoxic chemotherapy, which can be manifested as neutropenia, lymphopenia, anemia, and thrombocytopenia. As such, myelosuppression is the source of many of the adverse side effects of cancer treatment including infection, sepsis, bleeding, and fatigue, thus resulting in the need for hospitalizations, hematopoietic growth factor support, and transfusions (red blood cells and/or platelets). Moreover, clinical concerns raised by myelosuppression commonly lead to chemotherapy dose reductions, therefore limiting therapeutic dose intensity, and reducing the antitumor effectiveness of the treatment. Currently, the only course of treatment for myelosuppression is growth factor support which is suboptimal. These treatments are lineage specific, do not protect the bone marrow from the chemotherapy-inducing cytotoxic effects, and the safety and toxicity of each agent is extremely specific. Here, we describe the preclinical development of G1T28, a novel potent and selective CDK4/6 inhibitor that transiently and reversibly regulates the proliferation of murine and canine bone marrow hematopoietic stem and progenitor cells and provides multilineage protection from the hematologic toxicity of chemotherapy. Furthermore, G1T28 does not decrease the efficacy of cytotoxic chemotherapy on RB1-deficient tumors. G1T28 is currently in clinical development for the reduction of chemotherapy-induced myelosuppression in first- and second-line treatment of small-cell lung cancer. Mol Cancer Ther; 15(5); 783-93. ©2016 AACR. PMID:26826116

  15. A blueprint for staging of murine melanocytic lesions based on the Cdk4 ( R24C/R24C ) ::Tyr- NRAS ( Q ) ( 61K ) model.

    PubMed

    Wurm, Elisabeth M T; Lin, Lynlee L; Ferguson, Blake; Lambie, Duncan; Prow, Tarl W; Walker, Graeme J; Soyer, H Peter

    2012-09-01

    It has been shown that gene mutations which drive the development of malignant melanoma (MM) in humans also lead to emergence of MM when engineered mice. However, little attention has been paid to the clinical and histopathological features of melanocytic lesions and their natural history in a given mouse model. This knowledge is crucial to enable us to understand how engineered mutations influence the initiation and evolution of melanocytic lesions, and/or for the use of mice as a preclinical model to test specific treatments. We recently reported the development of melanocytic proliferations along the spectrum of naevi to MM in a Cdk4 ( R24C/R24C ) ::Tyr- NRAS ( Q ) ( 61K ) mouse model. In this study, we followed the development of lesions over time using digital photography and dermoscopy with the aim to correlate the clinical and histopathological features of lesions developing in this model. We identified two types of lesions. The first are slow-growing dermal MMs that emanate from dermal naevi. The second did not emanate from naevi, grew rapidly, and appeared to be solely confined to the subcutaneous fat. We present a simple staging system for the MMs that progress from naevi, based on depth of extension into the dermis and subcutis. This represents a blueprint for documentation and follow-up of MMs in the live animal, which is critical for the proper use of murine melanoma models. PMID:22742762

  16. Exergames: Increasing Physical Activity through Effective Instruction

    ERIC Educational Resources Information Center

    Rudella, Jennifer L.; Butz, Jennifer V.

    2015-01-01

    Due to the growing obesity epidemic in the United States, educators must consider new ways to increase physical activity in an effort to address obesity. There are a variety of ways educators can increase physical activity in the classroom, and exergames--video games that require physical movement in order to play--are a modern-day approach to…

  17. Analysis of the miR-34a locus in 62 patients with familial cutaneous melanoma negative for CDKN2A/CDK4 screening.

    PubMed

    Cozzolino, Angela M; Pedace, Lucia; Castori, Marco; De Simone, Paola; Preziosi, Nicoletta; Sperduti, Isabella; Panetta, Chiara; Mogini, Valerio; De Bernardo, Carmelilia; Morrone, Aldo; Catricalà, Caterina; Grammatico, Paola

    2012-06-01

    MicroRNAs are small non-coding RNAs, which inhibit expression of specific target genes at the post-transcriptional level and are often misregulated in human cancer. Among them, miR-34a is considered a tumor suppressor with a hypothetical role in melanoma tumorigenesis. In this work, 62 Italian index patients with familial melanoma and negative for CDKN2A/CDK4 screening were investigated for miR-34a germline mutations. Eight novel miR-34a sequence variants were identified at both the heterozygous (c.+259G>A, c.+424G>A, c.+1465C>T, c.+1769C>T, c.+2456T>G, c.+2603C>T, c.+2972T>A, c.+3069T>C) and homozygous (c.+424G>A, c.+1465C>T, c.+1769C>T) states. Molecular screening identified all nucleotide changes in a healthy population of 150 controls and demonstrated that they are common polymorphisms. However, statistically significant differences of allele and genotype frequencies were detected for c.+1465C>T and c.+1769C>T, and borderline values for c.+2456T>G. By stratifying patients by relevant clinical features (presence/absence of multiple primary melanoma, Breslow's thickness, phototype and number of nevi), no significant findings were noted except for an association between the c.+424G>A (heterozygous individual GA) and multiple primary melanoma and phototype III-IV. Our preliminary study suggests that miR-34a, although having a role in late tumorigenesis, does not contribute to the inherited susceptibility to cutaneous melanoma. A function as phenotypic modulator in familial melanoma cannot be excluded. PMID:22198089

  18. Increased alveolar plasminogen activator in early asbestosis

    SciTech Connect

    Cantin, A.; Allard, C.; Begin, R.

    1989-03-01

    Alveolar macrophage-derived plasminogen activator (PA) activity is decreased in some chronic interstitial lung diseases such as idiopathic pulmonary fibrosis and sarcoidosis but increased in experimental models of acute alveolitis. Although asbestos fibers can stimulate alveolar macrophages (AM) to release PA in vitro, the effect of chronic asbestos exposure of the lower respiratory tract on lung PA activity remains unknown. The present study was designed to evaluate PA activity of alveolar macrophages and bronchoalveolar lavage (BAL) fluid in asbestos-exposed sheep and asbestos workers. Forty-three sheep were exposed to either 100 mg UICC chrysotile B asbestos in 100 ml phosphate-buffered saline (PBS) or to 100 ml PBS by tracheal infusion every 2 wk for 18 months. At Month 18, chest roentgenograms were analyzed and alveolar macrophage and extracellular fluid PA activity were measured in samples obtained by BAL. Alveolar macrophage PA activity was increased in the asbestos-exposed sheep compared to control sheep (87.2 +/- 17.3 versus 41.1 +/- 7.2 U/10(5) AM-24 h, p less than 0.05) as was the BAL fluid PA activity (674.9 +/- 168.4 versus 81.3 +/- 19.7 U/mg alb-24 h, p less than 0.01). Among the asbestos-exposed sheep, 10 had normal chest roentgenograms (Group SA) and 15 had irregular interstitial opacities (Group SB). Strikingly, whereas Group SA did not differ from the control group in BAL cellularity or PA activity, Group SB had marked increases in alveolar macrophages (p less than 0.005), AM PA activity (p less than 0.02), and BAL PA activity (p less than 0.001) compared to the control group.

  19. Increased Ribozyme Activity in Crowded Solutions*

    PubMed Central

    Desai, Ravi; Kilburn, Duncan; Lee, Hui-Ting; Woodson, Sarah A.

    2014-01-01

    Noncoding RNAs must function in the crowded environment of the cell. Previous small-angle x-ray scattering experiments showed that molecular crowders stabilize the structure of the Azoarcus group I ribozyme, allowing the ribozyme to fold at low physiological Mg2+ concentrations. Here, we used an RNA cleavage assay to show that the PEG and Ficoll crowder molecules increased the biochemical activity of the ribozyme, whereas sucrose did not. Crowding lowered the Mg2+ threshold at which activity was detected and increased total RNA cleavage at high Mg2+ concentrations sufficient to fold the RNA in crowded or dilute solution. After correcting for solution viscosity, the observed reaction rate was proportional to the fraction of active ribozyme. We conclude that molecular crowders stabilize the native ribozyme and favor the active structure relative to compact inactive folding intermediates. PMID:24337582

  20. Altered mRNA expression of the Rb and p16 tumor suppressor genes and of CDK4 in transitional cell carcinomas of the urinary bladder associated with tumor progression.

    PubMed

    Quentin, Thomas; Henke, Christian; Korabiowska, Monika; Schlott, Thilo; Zimmerman, Britt; Kunze, Ekkehard

    2004-01-01

    Based on the concept that tumor suppressor genes are involved in the pathogenesis of urinary bladder carcinogenesis, we analysed the mRNA expression of the retinoblastoma (Rb) and p16 (CDKN2, INK4A, MTS1) genes as well as of the proto-oncogene cyclin D-dependent kinase 4 (CDK4) in 71 transitional cell carcinomas (TCC) of the urinary bladder in relation to the tumor grades and stages, and with reference to certain lifestyle and occupational risk factors. Using real-time quantitative reverse transcription-polymerase chain reaction, high-stage muscle invasive TCC expressed the Rb, p16 and CDK4 mRNA at lower levels than low-stage superficial cancers, indicating down-regulation to be linked with tumor progression. The drop of the expression in the group of grade 2 TCC when invading the muscle layer compared to grade 2 carcinomas with a superficial pattern of growth is considered to represent a key event in promoting urothelial carcinogenesis in this subset of carcinomas. The protein expression of the Rb gene evaluated by immunohistochemistry proved to be closely related to the tumor grades and stages as well as to the mRNA expression, high-grade and high-stage TCC disclosing a lower rate of positive immunoreactivity than low-grade and low-stage carcinomas. The p16 protein product was expressed at a lower level in grade 3 than in grade 1 TCC, but there was no correlation with the tumor stages or the mRNA expression. TCC with loss of heterozygosity (LOH) at the INK4A region showed a decreased expression of p16 mRNA compared to those without an allelic loss. Tobacco smoke was not identified to substantially modulate the Rb/p16/CDK4 pathways, except for a ten-fold elevated mRNA expression of the p16 gene in TCC of light compared to heavy smokers. Heavy coffee consumption was associated with a reduced expression of CDK4 mRNA. Among occupational exposures, TCC of patients in contact with stone dust, paints and lacquer, plastics, wood and wood preservers and chemical solvents

  1. Bufalin induces G0/G1 phase arrest through inhibiting the levels of cyclin D, cyclin E, CDK2 and CDK4, and triggers apoptosis via mitochondrial signaling pathway in T24 human bladder cancer cells.

    PubMed

    Huang, Wen-Wen; Yang, Jai-Sing; Pai, Shu-Jen; Wu, Ping-Ping; Chang, Shu-Jen; Chueh, Fu-Shin; Fan, Ming-Jen; Chiou, Shang-Ming; Kuo, Hsiu-Maan; Yeh, Chin-Chung; Chen, Po-Yuan; Tsuzuki, Minoru; Chung, Jing-Gung

    2012-04-01

    Most of the chemotherapy treatments for bladder cancer aim to kill the cancer cells, but a high recurrence rate after medical treatments is still occurred. Bufalin from the skin and parotid venom glands of toad has been shown to induce apoptotic cell death in many types of cancer cell lines. However, there is no report addressing that bufalin induced cell death in human bladder cancer cells. The purpose of this study was investigated the mechanisms of bufalin-induced apoptosis in a human bladder cancer cell line (T24). We demonstrated the effects of bufalin on the cell growth and apoptosis in T24 cells by using DAPI/TUNEL double staining, a PI exclusion and flow cytometric analysis. The effects of bufalin on the production of reactive oxygen species (ROS), the level of mitochondrial membrane potential (ΔΨ(m)), and DNA content including sub-G1 (apoptosis) in T24 cells were also determined by flow cytometry. Western blot analysis was used to examine the expression of G(0)/G(1) phase-regulated and apoptosis-associated protein levels in bufalin-treated T24 cells. The results indicated that bufalin significantly decreased the percentage of viability, induced the G(0)/G(1) phase arrest and triggered apoptosis in T24 cells. The down-regulation of the protein levels for cyclin D, CDK4, cyclin E, CDK2, phospho-Rb, phospho-AKT and Bcl-2 with the simultaneous up-regulation of the cytochrome c, Apaf-1, AIF, caspase-3, -7 and -9 and Bax protein expressions and caspase activities were observed in T24 cells after bufalin treatment. Based on our results, bufalin induces apoptotic cell death in T24 cells through suppressing AKT activity and anti-apoptotic Bcl-2 protein as well as inducing pro-apoptotic Bax protein. The levels of caspase-3, -7 and -9 are also mediated apoptosis in bufalin-treated T24 cells. Therefore, bufalin might be used as a therapeutic agent for the treatment of human bladder cancer in the future. PMID:22285700

  2. Addressing childhood obesity through increased physical activity.

    PubMed

    Hills, Andrew P; Okely, Anthony D; Baur, Louise A

    2010-10-01

    Obesity is affecting an increasing proportion of children globally. Despite an appreciation that physical activity is essential for the normal growth and development of children and prevents obesity and obesity-related health problems, too few children are physically active. A concurrent problem is that today's young people spend more time than previous generations did in sedentary pursuits, including watching television and engaging in screen-based games. Active behavior has been displaced by these inactive recreational choices, which has contributed to reductions in activity-related energy expenditure. Implementation of multifactorial solutions considered to offer the best chance of combating these trends is urgently required to redress the energy imbalance that characterizes obesity. The counterproductive 'shame and blame' mentality that apportions responsibility for the childhood obesity problem to sufferers, their parents, teachers or health-care providers needs to be changed. Instead, these groups should offer constant support and encouragement to promote appropriate physical activity in children. Failure to provide activity opportunities will increase the likelihood that the children of today will live less healthy (and possibly shorter) lives than their parents. PMID:20736922

  3. Tooth Bleaching Increases Dentinal Protease Activity

    PubMed Central

    Sato, C.; Rodrigues, F.A.; Garcia, D.M.; Vidal, C.M.P.; Pashley, D.H.; Tjäderhane, L.; Carrilho, M.R.; Nascimento, F.D.; Tersariol, I.L.S.

    2012-01-01

    Hydrogen peroxide is an oxidative agent commonly used for dental bleaching procedures. The structural and biochemical responses of enamel, dentin, and pulp tissues to the in vivo bleaching of human (n = 20) premolars were investigated in this study. Atomic force microscopy (AFM) was used to observe enamel nanostructure. The chemical composition of enamel and dentin was analyzed by infrared spectroscopy (FTIR). The enzymatic activities of dental cathepsin B and matrix metalloproteinases (MMPs) were monitored with fluorogenic substrates. The amount of collagen in dentin was measured by emission of collagen autofluorescence with confocal fluorescence microscopy. The presence of Reactive Oxygen Species (ROS) in the pulp was evaluated with a fluorogenic 2′,7′-dichlorodihydrofluorescein diacetate (DCFDA) probe. Vital bleaching of teeth significantly altered all tested parameters: AFM images revealed a corrosion of surface enamel nanostructure; FTIR analysis showed a loss of carbonate and proteins from enamel and dentin, along with an increase in the proteolytic activity of cathepsin-B and MMPs; and there was a reduction in the autofluorescence of collagen and an increase in both cathepsin-B activity and ROS in pulp tissues. Together, these results indicate that 35% hydrogen peroxide used in clinical bleaching protocols dramatically alters the structural and biochemical properties of dental hard and soft pulp tissue. PMID:23242228

  4. Discovery of 8-Cyclopentyl-2-[4-(4-methyl-piperazin-1-yl)-phenylamino]-7-oxo-7,8-dihydro-pyrido[2,3-d]pyrimidine-6-carbonitrile (7x) as a Potent Inhibitor of Cyclin-Dependent Kinase 4 (CDK4) and AMPK-Related Kinase 5 (ARK5)

    PubMed Central

    2015-01-01

    The success of imatinib, a BCR-ABL inhibitor for the treatment of chronic myelogenous leukemia, has created a great impetus for the development of additional kinase inhibitors as therapeutic agents. However, the complexity of cancer has led to recent interest in polypharmacological approaches for developing multikinase inhibitors with low toxicity profiles. With this goal in mind, we analyzed more than 150 novel cyano pyridopyrimidine compounds and identified structure–activity relationship trends that can be exploited in the design of potent kinase inhibitors. One compound, 8-cyclopentyl-2-[4-(4-methyl-piperazin-1-yl)-phenylamino]-7-oxo-7,8-dihydro-pyrido[2,3-d]pyrimidine-6-carbonitrile (7x), was found to be the most active, inducing apoptosis of tumor cells at a concentration of approximately 30–100 nM. In vitro kinase profiling revealed that 7x is a multikinase inhibitor with potent inhibitory activity against the CDK4/CYCLIN D1 and ARK5 kinases. Here, we report the synthesis, structure–activity relationship, kinase inhibitory profile, in vitro cytotoxicity, and in vivo tumor regression studies by this lead compound. PMID:24417566

  5. The p16(INK4A)/pRb pathway and telomerase activity define a subgroup of Ph+ adult Acute Lymphoblastic Leukemia associated with inferior outcome.

    PubMed

    Chien, Wei W; Catallo, Régine; Chebel, Amel; Baranger, Laurence; Thomas, Xavier; Béné, Marie-Christine; Gerland, Luc M; Schmidt, Aline; Beldjord, Kheira; Klein, Nathalie; Escoffre-Barbe, Martine; Leguay, Thibaut; Huguet, Françoise; Larosa, Fabrice; Hayette, Sandrine; Plesa, Adriana; Ifrah, Norbert; Dombret, Hervé; Salles, Gilles; Chassevent, Agnès; Ffrench, Martine

    2015-04-01

    Adult Acute Lymphoblastic Leukemia (ALL) therapies have been improved by pediatric-like approaches. However, treatment failures and relapses are common and new markers are needed to identify patients with poor prognosis in prospective trials. The p16(INK4A)/CDK4-6/pRb pathway and telomerase activity, which are implicated in cell activation and aging, were analyzed to identify new prognostic markers. Proteins of the p16(INK4A)/CDK4-6/pRb pathway and telomerase activity were analyzed in 123 adult B-cell precursor (BCP) ALL cases included in the GRAALL/GRAAPH trials. We found a significantly increased expression of p16(INK4A) in BCP-ALLs with MLL rearrangement. Telomerase activity was significantly lower in Philadelphia chromosome-negative/IKAROS-deleted (BCR-ABL1(-)/IKAROS(del)) cases compared to Philadelphia chromosome-positive (BCR-ABL1+) BCP-ALLs. In BCR-ABL1+ ALLs, high CDK4 expression, phosphorylated pRb (p-pRb) and telomerase activity were significantly associated with a shorter disease-free survival (DFS) and event-free survival (EFS). Enhanced p16(INK4A) expression was only related to a significantly shorter DFS. In vitro analyses of normal stimulated lymphocytes after short- and long-term cultures demonstrated that the observed protein variations of poor prognosis in BCR-ABL1+ ALLs may be related to cell activation but not to cell aging. For these patients, our findings argue for the development of therapeutic strategies including the addition of new lymphocyte activation inhibitors to current treatments. PMID:25675863

  6. School Programs to Increase Physical Activity

    ERIC Educational Resources Information Center

    Lee, Amelia; Solmon, Melinda

    2007-01-01

    A quality physical education program is at the heart of any plan to promote lifelong participation in physical activity, but it has become evident at many schools that physical education specialists alone cannot address the physical activity needs of children. This is why a series of studies were conducted to develop strategies for the…

  7. Increasing Physical Activity through Recess. Research Brief

    ERIC Educational Resources Information Center

    Beighle, Aaron

    2012-01-01

    Regular physical activity promotes important health benefits, reduces risk for obesity and is linked with enhanced academic performance among students. The U.S. Surgeon General recommends that children engage in at least 60 minutes of moderate physical activity most days of the week, yet fewer than half of children ages 6 to 11 meet that…

  8. Fisetin inhibits the activities of cyclin-dependent kinases leading to cell cycle arrest in HT-29 human colon cancer cells.

    PubMed

    Lu, Xianghua; Jung, Jae in; Cho, Han Jin; Lim, Do Young; Lee, Hyun Sook; Chun, Hyang Sook; Kwon, Dae Young; Park, Jung Han Yoon

    2005-12-01

    Fisetin, a natural flavonol present in edible vegetables, fruits, and wine, was reported to exert anticarcinogenic effects. The objective of the current study was to examine the effect of fisetin on the cell cycle progression of the human colon cancer cell line HT-29. HT-29 cells were cultured in serum-free medium with 0, 20, 40, or 60 micromol/L fisetin. Fisetin dose dependently inhibited both cell growth and DNA synthesis (P < 0.05), with a 79 +/- 1% decrease in cell number observed 72 h after the addition of 60 micromol/L fisetin. Perturbed cell cycle progression from the G(1) to S phase was observed at 8 h with 60 micromol/L fisetin treatment, whereas a G(2)/M phase arrest was observed after 24 h (P < 0.05). The phosphorylation state of the retinoblastoma proteins shifted from hyperphosphorylated to hypophosphorylated in cells treated with 40 micromol/L fisetin. (P < 0.05). Fisetin decreased the activities of cyclin-dependent kinases (CDK)2 and CDK4; these effects were likely attributable to decreases in the levels of cyclin E and D1 and an increase in p21(CIP1/WAF1) levels (P < 0.05). However, fisetin also inhibited CDk4 activity in a cell-free system (P < 0.05), indicating that it may directly inhibit CDk4 activity. The protein levels of cell division cycles (CDC)2 and CDC25C and the activity of CDC2 were also decreased in fisetin-treated cells (P < 0.05). These results indicate that inhibition of cell cycle progression in HT-29 cells after treatment with fisetin can be explained, at least in part, by modification of CDK activities. PMID:16317137

  9. Ectopic expression of cyclin D3 corrects differentiation of DM1 myoblasts through activation of RNA CUG-binding protein, CUGBP1

    SciTech Connect

    Salisbury, Elizabeth; Sakai, Keiko; Schoser, Benedikt; Huichalaf, Claudia; Schneider-Gold, Christiane; Nguyen, Heather; Wang, Gou-Li; Albrecht, Jeffrey H.; Timchenko, Lubov T.

    2008-07-01

    Differentiation of myocytes is impaired in patients with myotonic dystrophy type 1, DM1. CUG repeat binding protein, CUGBP1, is a key regulator of translation of proteins that are involved in muscle development and differentiation. In this paper, we present evidence that RNA-binding activity of CUGBP1 and its interactions with initiation translation complex eIF2 are differentially regulated during myogenesis by specific phosphorylation and that this regulation is altered in DM1. In normal myoblasts, Akt kinase phosphorylates CUGBP1 at Ser28 and increases interactions of CUGBP1 with cyclin D1 mRNA. During differentiation, CUGBP1 is phosphorylated by cyclinD3-cdk4/6 at Ser302, which increases CUGBP1 binding with p21 and C/EBP{beta} mRNAs. While cyclin D3 and cdk4 are elevated in normal myotubes; DM1 differentiating cells do not increase these proteins. In normal myotubes, CUGBP1 interacts with cyclin D3/cdk4/6 and eIF2; however, interactions of CUGBP1 with eIF2 are reduced in DM1 differentiating cells and correlate with impaired muscle differentiation in DM1. Ectopic expression of cyclin D3 in DM1 cells increases the CUGBP1-eIF2 complex, corrects expression of differentiation markers, myogenin and desmin, and enhances fusion of DM1 myoblasts. Thus, normalization of cyclin D3 might be a therapeutic approach to correct differentiation of skeletal muscle in DM1 patients.

  10. Selective anticancer activity of a hexapeptide with sequence homology to a non-kinase domain of Cyclin Dependent Kinase 4

    PubMed Central

    2011-01-01

    Background Cyclin-dependent kinases 2, 4 and 6 (Cdk2, Cdk4, Cdk6) are closely structurally homologous proteins which are classically understood to control the transition from the G1 to the S-phases of the cell cycle by combining with their appropriate cyclin D or cyclin E partners to form kinase-active holoenzymes. Deregulation of Cdk4 is widespread in human cancer, CDK4 gene knockout is highly protective against chemical and oncogene-mediated epithelial carcinogenesis, despite the continued presence of CDK2 and CDK6; and overexpresssion of Cdk4 promotes skin carcinogenesis. Surprisingly, however, Cdk4 kinase inhibitors have not yet fulfilled their expectation as 'blockbuster' anticancer agents. Resistance to inhibition of Cdk4 kinase in some cases could potentially be due to a non-kinase activity, as recently reported with epidermal growth factor receptor. Results A search for a potential functional site of non-kinase activity present in Cdk4 but not Cdk2 or Cdk6 revealed a previously-unidentified loop on the outside of the C'-terminal non-kinase domain of Cdk4, containing a central amino-acid sequence, Pro-Arg-Gly-Pro-Arg-Pro (PRGPRP). An isolated hexapeptide with this sequence and its cyclic amphiphilic congeners are selectively lethal at high doses to a wide range of human cancer cell lines whilst sparing normal diploid keratinocytes and fibroblasts. Treated cancer cells do not exhibit the wide variability of dose response typically seen with other anticancer agents. Cancer cell killing by PRGPRP, in a cyclic amphiphilic cassette, requires cells to be in cycle but does not perturb cell cycle distribution and is accompanied by altered relative Cdk4/Cdk1 expression and selective decrease in ATP levels. Morphological features of apoptosis are absent and cancer cell death does not appear to involve autophagy. Conclusion These findings suggest a potential new paradigm for the development of broad-spectrum cancer specific therapeutics with a companion diagnostic

  11. Structural Basis for the Modulation of CDK-Dependent/Independent Activity of Cyclin D1

    PubMed Central

    Ferrer, Jean-Luc; Dupuy, Jérôme; Borel, Franck; Jacquamet, Lilian; Noel, Joseph P.; Dulic, Vjekoslav

    2010-01-01

    D-type cyclins are key regulators of the cell division cycle. In association with Cyclin Dependent Kinases (CDK) 2/4/6, they control the G1/S-phase transition in part by phosphorylation and inactivation of tumor suppressor of retinoblastoma family. Defective regulation of the G1/S transition is a well-known cause of cancer, making the cyclin D1-CDK4/6 complex a promising therapeutic target. Our objective is to develop inhibitors that would block the formation or the activation of the cyclin D1-CDK4/6 complex, using in silico docking experiments on a structural homology model of the cyclin D1-CDK4/6 complex. To this end we focused on the cyclin subunit in three different ways: (1) targeting the part of the cyclin D1 facing the N-terminal domain of CDK4/6, in order to prevent the dimer formation; (2) targeting the part of the cyclin D1 facing the C-terminal domain of CDK4/6, in order to prevent the activation of CDK4/6 by blocking the T-loop in an inactive conformation, and also to destabilize the dimer; (3) targeting the groove of cyclin D1 where p21 binds, in order to mimic its inhibition mode by preventing binding of cyclin D1-CDK4/6 complex to its targets. Our strategy, and the tools we developed, will provide a computational basis to design lead compounds for novel cancer therapeutics, targeting a broad range of proteins involved in the regulation of the cell cycle. PMID:17172845

  12. How Active Are Your Students? Increasing Physical Activity in Schools

    ERIC Educational Resources Information Center

    Avery, Marybell; Brandt, Janet

    2010-01-01

    The U. S. Department of Health and Human Services recommends that youth engage in at least 60 minutes of physical activity each day, most of which should be either moderate- or vigorous-intensity aerobic physical activity. Half of this amount (30 minutes) should be achieved during the school day. NASPE provides guidance in the form of a…

  13. Inhibition of Rb Phosphorylation Leads to mTORC2-Mediated Activation of Akt.

    PubMed

    Zhang, Jinfang; Xu, Kai; Liu, Pengda; Geng, Yan; Wang, Bin; Gan, Wenjian; Guo, Jianping; Wu, Fei; Chin, Y Rebecca; Berrios, Christian; Lien, Evan C; Toker, Alex; DeCaprio, James A; Sicinski, Piotr; Wei, Wenyi

    2016-06-16

    The retinoblastoma (Rb) protein exerts its tumor suppressor function primarily by inhibiting the E2F family of transcription factors that govern cell-cycle progression. However, it remains largely elusive whether the hyper-phosphorylated, non-E2F1-interacting form of Rb has any physiological role. Here we report that hyper-phosphorylated Rb directly binds to and suppresses the function of mTORC2 but not mTORC1. Mechanistically, Rb, but not p107 or p130, interacts with Sin1 and blocks the access of Akt to mTORC2, leading to attenuated Akt activation and increased sensitivity to chemotherapeutic drugs. As such, inhibition of Rb phosphorylation by depleting cyclin D or using CDK4/6 inhibitors releases Rb-mediated mTORC2 suppression. This, in turn, leads to elevated Akt activation to confer resistance to chemotherapeutic drugs in Rb-proficient cells, which can be attenuated with Akt inhibitors. Therefore, our work provides a molecular basis for the synergistic usage of CDK4/6 and Akt inhibitors in treating Rb-proficient cancer. PMID:27237051

  14. Enhancement of DNA repair using topical T4 endonuclease V does not inhibit melanoma formation in Cdk4(R24C/R24C)/Tyr-Nras(Q61K) mice following neonatal UVR.

    PubMed

    Hacker, Elke; Muller, H Konrad; Hayward, Nicholas; Fahey, Paul; Walker, Graeme

    2010-02-01

    To further investigate the use of DNA repair-enhancing agents for skin cancer prevention, we treated Cdk4(R24C/R24C)/Nras(Q61K) mice topically with the T4 endonuclease V DNA repair enzyme (known as Dimericine) immediately prior to neonatal ultraviolet radiation (UVR) exposure, which has a powerful effect in exacerbating melanoma development in the mouse model. Dimericine has been shown to reduce the incidence of basal-cell and squamous cell carcinoma. Unexpectedly, we saw no difference in penetrance or age of onset of melanoma after neonatal UVR between Dimericine-treated and control animals, although the drug reduced DNA damage and cellular proliferation in the skin. Interestingly, epidermal melanocytes removed cyclobutane pyrimidine dimers (CPDs) more efficiently than surrounding keratinocytes. Our study indicates that neonatal UVR-initiated melanomas may be driven by mechanisms other than solely that of a large CPD load and/or their inefficient repair. This is further suggestive of different mechanisms by which UVR may enhance the transformation of keratinocytes and melanocytes. PMID:19788533

  15. DACH1 regulates cell cycle progression of myeloid cells through the control of cyclin D, Cdk 4/6 and p21{sup Cip1}

    SciTech Connect

    Lee, Jae-Woong; Kim, Hyeng-Soo; Kim, Seonggon; Hwang, Junmo; Kim, Young Hun; Lim, Ga Young; Sohn, Wern-Joo; Yoon, Suk-Ran; Kim, Jae-Young; Park, Tae Sung; Park, Kwon Moo; Ryoo, Zae Young; Lee, Sanggyu

    2012-03-30

    Highlights: Black-Right-Pointing-Pointer DACH1 increases cyclin D, F and Cdk 1, 4, 6 in mouse myeloid progenitor cells. Black-Right-Pointing-Pointer The knockdown of DACH1 blocked the cell cycle progression of HL-60 cells. Black-Right-Pointing-Pointer The novel effect of DACH1 related with cell cycle regulation and leukemogenesis. -- Abstract: The cell-fate determination factor Dachshund, a component of the Retinal Determination Gene Network (RDGN), has a role in breast tumor proliferation through the repression of cyclin D1 and several key regulators of embryonic stem cell function, such as Nanog and Sox2. However, little is known about the role of DACH1 in a myeloid lineage as a cell cycle regulator. Here, we identified the differential expression levels of extensive cell cycle regulators controlled by DACH1 in myeloid progenitor cells. The forced expression of DACH1 induced p27{sup Kip1} and repressed p21{sup Cip1}, which is a pivotal characteristic of the myeloid progenitor. Furthermore, DACH1 significantly increased the expression of cyclin D1, D3, F, and Cdk 1, 4, and 6 in myeloid progenitor cells. The knockdown of DACH1 blocked the cell cycle progression of HL-60 promyeloblastic cells through the decrease of cyclin D1, D3, F, and Cdk 1, 4, and 6 and increase in p21{sup Cip1}, which in turn decreased the phosphorylation of the Rb protein. The expression of Sox2, Oct4, and Klf4 was significantly up-regulated by the forced expression of DACH1 in mouse myeloid progenitor cells.

  16. Best Practices and Recommendations for Increasing Physical Activity in Youth

    ERIC Educational Resources Information Center

    Erwin, Heather; Beets, Michael W.; Centeio, Erin; Morrow, James R., Jr.

    2014-01-01

    Many efforts to increase the physical activity levels of Americans have been introduced and implemented over the past 20 years. National Physical Activity Guidelines have been established, and the National Physical Activity Plan (NPAP) is now in place, which includes a specific sector dedicated to education. This article addresses the Education…

  17. Increased expression of β-glucosidase A in Clostridium thermocellum 27405 significantly increases cellulase activity

    PubMed Central

    Maki, Miranda L.; Armstrong, Lachlan; Leung, Kam Tin; Qin, Wensheng

    2013-01-01

    β-glucosidase A (bglA) in Clostridium thermocellum 27405 was increased by expression from shuttle vector pIBglA in attempts to increase cellulase activity and ethanol titer by lowering the end product inhibition of cellulase. Through a modified electrotransformation protocol C. thermocellum transformant (+MCbglA) harbouring pIBglA was produced. The β-glucosidase activity of +MCbglA was 2.3- and 1.6-fold greater than wild-type (WT) during late log and stationary phases of growth. Similarly, total cellulase activity of +MCbglA was shown to be 1.7-, 2.3- and 1.6-fold greater than WT during, log, late log and stationary phases of growth. However, there was no significant correlation found between increased cellulase activity and increased ethanol titers for +MCbglA compared with the WT. C. thermocellum has industrial potential for consolidated bioprocessing (CBP) to make a more cost effective production of biofuels; however, the hydrolysis rate of the strain is still hindered by end product inhibition. We successfully increased total cellulase activity by increased expression of bglA and thereby increased the productivity of C. thermocellum during the hydrolysis stage in CBP. Our work also lends insights into the complex metabolism of C. thermocellum for future improvement of this strain. PMID:22922214

  18. Jealousy increased by induced relative left frontal cortical activity.

    PubMed

    Kelley, Nicholas J; Eastwick, Paul W; Harmon-Jones, Eddie; Schmeichel, Brandon J

    2015-10-01

    Asymmetric frontal cortical activity may be one key to the process linking social exclusion to jealous feelings. The current research examined the causal role of asymmetric frontal brain activity in modulating jealousy in response to social exclusion. Transcranial direct-current stimulation (tDCS) over the frontal cortex to manipulate asymmetric frontal cortical activity was combined with a modified version of the Cyberball paradigm designed to induce jealousy. After receiving 15 min of tDCS, participants were excluded by a desired partner and reported how jealous they felt. Among individuals who were excluded, tDCS to increase relative left frontal cortical activity caused greater levels of self-reported jealousy compared to tDCS to increase relative right frontal cortical activity or sham stimulation. Limitations concerning the specificity of this effect and implications for the role of the asymmetric prefrontal cortical activity in motivated behaviors are discussed. PMID:25844975

  19. Building a better mousetrap (exergame) to increase youth physical activity

    Technology Transfer Automated Retrieval System (TEKTRAN)

    While exergames have been demonstrated to induce moderate levels of physical activity (PA) if played as designed, there is conflicting evidence on use of exergaming leading to increased habitual PA. Exergames have increased PA in some home and school studies, but not others. Exergames have been us...

  20. Development of an active boring bar for increased chatter immunity

    SciTech Connect

    Redmond, J.; Barney, P.; Smith, D.

    1997-03-01

    The development and initial evaluation of a prototype boring bar featuring active vibration control for increased chatter immunity is described. The significance of active damping both normal and tangential to the workpiece surface is evaluated, indicating the need for two axis control to ensure adequate performance over expected variations in tool mounting procedures. The prototype tool features a commercially available boring bar modified to accommodate four PZT stack actuators for two axis bending control. Measured closed-loop dynamics are combined with a computer model of the boring process to simulate increased metal removal rate and improved workpiece surface finish through active control.

  1. Cerebellar fMRI Activation Increases with Increasing Working Memory Demands.

    PubMed

    Küper, M; Kaschani, P; Thürling, M; Stefanescu, M R; Burciu, R G; Göricke, S; Maderwald, S; Ladd, M E; Hautzel, H; Timmann, D

    2016-06-01

    The aim of the present study was to explore cerebellar contributions to the central executive in n-back working memory tasks using 7-T functional magnetic imaging (fMRI). We hypothesized that cerebellar activation increased with increasing working memory demands. Activations of the cerebellar cortex and dentate nuclei were compared between 0-back (serving as a motor control task), 1-back, and 2-back working memory tasks for both verbal and abstract modalities. A block design was used. Data of 27 participants (mean age 26.6 ± 3.8 years, female/male 12:15) were included in group statistical analysis. We observed that cerebellar cortical activations increased with higher central executive demands in n-back tasks independent of task modality. As confirmed by subtraction analyses, additional bilateral activations following higher executive demands were found primarily in four distinct cerebellar areas: (i) the border region of lobule VI and crus I, (ii) inferior parts of the lateral cerebellum (lobules crus II, VIIb, VIII, IX), (iii) posterior parts of the paravermal cerebellar cortex (lobules VI, crus I, crus II), and (iv) the inferior vermis (lobules VI, VIIb, VIII, IX). Dentate activations were observed for both verbal and abstract modalities. Task-related increases were less robust and detected for the verbal n-back tasks only. These results provide further evidence that the cerebellum participates in an amodal bilateral neuronal network representing the central executive during working memory n-back tasks. PMID:26202670

  2. Increasing physical activity through mobile device interventions: A systematic review.

    PubMed

    Muntaner, Adrià; Vidal-Conti, Josep; Palou, Pere

    2016-09-01

    Physical inactivity is a health problem that affects people worldwide and has been identified as the fourth largest risk factor for overall mortality (contributing to 6% of deaths globally). Many researchers have tried to increase physical activity levels through traditional methods without much success. Thus, many researchers are turning to mobile technology as an emerging method for changing health behaviours. This systematic review sought to summarise and update the existing scientific literature on increasing physical activity through mobile device interventions, taking into account the methodological quality of the studies. The articles were identified by searching the PubMed, SCOPUS and SPORTDiscus databases for studies published between January 2003 and December 2013. Studies investigating efforts to increase physical activity through mobile phone or even personal digital assistant interventions were included. The search results allowed the inclusion of 11 studies that gave rise to 12 publications. Six of the articles included in this review reported significant increases in physical activity levels. The number of studies using mobile devices for interventions has increased exponentially in the last few years, but future investigations with better methodological quality are needed to draw stronger conclusions regarding how to increase physical activity through mobile device interventions. PMID:25649783

  3. [Increase of physical activity by improvement of the nutritional status].

    PubMed

    Torún, B

    1989-09-01

    Physical activity is affected by nutritional modifications and, in turn, influences growth, cognition, social behavior, work performance and other functions. Studies in preschool children showed that: 1. A decrease in energy intake during four to seven days reduced the time allocated to energy-demanding activities and increased sedentary activities. 2. Children with mild weight deficit were more sedentary than well-nourished counterparts. 3. Children became more active when nutritional status improved. 4. A 10% reduction in energy intake reduced total energy expenditure by 15% without affecting weight gain nor basal metabolism. Studies of men working in non-mechanized agriculture showed that: 1. Dietary improvements led to faster salaried work, reduction of napping time and greater physical activity after work. 2. An increase in energy intake increased total daily energy expenditure, tending to maintain energy balance and relatively stable body weight within the cyclic variations of the agricultural year. 3. Food supplementation did not necessarily improve productivity. Other labor incentives without dietary improvements increased energy expenditure during working hours, which resulted in weight loss. In conclusion, good health and nutrition provide the biological basis for adequate physical activity that may improve cognitive development, social interactions, economic productivity and the quality of life of an individual or a population, but other incentives are required for the optimal expression of that biologic potential. PMID:2518785

  4. Walking with wider steps increases stance phase gluteus medius activity

    PubMed Central

    Kubinski, Samantha N.; McQueen, Christina A.; Sittloh, Keir A.; Dean, Jesse C.

    2014-01-01

    Increases in step width have been reported for several clinical populations, including older adults and stroke survivors. These populations often also exhibit decreased hip abductor strength, suggesting that walking with wider steps may be an adaptive response in order to reduce the mechanical demands on the hip abductors. The purpose of this study was to quantify the relationship between step width and gluteus medius (GM) activity during walking. Fourteen young, uninjured adults walked on a treadmill at 1.25 m/s for four step width conditions (Normal, Narrow, Medium, and Wide) while step width and stance phase GM electromyographic (EMG) activity were quantified. We also measured hip abduction torque and GM activity during maximum voluntary isometric contractions (MVICs) at three hip angles (neutral, abducted 10°, and abducted 20°). During walking trials, GM activity was significantly (p<0.0001) influenced by step width; compared to Normal walking, GM activity was 47% higher with Wide steps and 24% lower with Narrow steps. We also observed a weak positive correlation (r=0.18±0.14) between step width and GM activity during Normal walking, as GM activity was higher with wider steps. These results cannot be attributed to changes in GM conformation under the recording electrode, as GM activity was not influenced by hip angle during MVICs. The increased GM activity with wider steps does not support the proposal that increasing step width would be a beneficial adaptation to weakened hip abductors. A likely alternative explanation is that increased step width is a response to decreased gait balance. PMID:25300241

  5. [Increased antibacterial activity of antibiotics with etonium in vitro].

    PubMed

    Petrunyk, I O

    2000-01-01

    The activity of compositions of antibiotics cefasolin, benzylpenicillin and gentamycin with etonium in respect to museum strains Staphylococcus aureus 209, Escherichia coli K-12, Proteus vulgaris 410, P. mirabilis, Pseudomonas aeruginosa 19, Klebsiella pneumoniae 5054 and polyresistance strains S. aureus, E. coli, P. mirabilis in vitro was researched. The increase of the compositions activity as a result of synergy in the action of their component 4 up to 4496 times has been established. PMID:11421003

  6. Increasing Arabian dust activity and the Indian Summer Monsoon

    NASA Astrophysics Data System (ADS)

    Solmon, F.; Nair, V. S.; Mallet, M.

    2015-02-01

    Over the past decade, Aerosol Optical Depth (AOD) observations based on satellite and ground measurements have shown a significant increase over Arabia and the Arabian Sea, attributed to an intensification of regional dust activity. Recent studies have also suggested that west Asian dust forcing could induce a positive response of Indian monsoon precipitations on a weekly time scale. Using observations and a regional climate model including interactive slab ocean and dust aerosol schemes, the present study investigates possible climatic links between the increasing June-July-August-September (JJAS) Arabian dust activity and precipitation trends over southern India during the 2000-2009 decade. Meteorological reanalysis and AOD observations suggest that the observed decadal increase of dust activity and a simultaneous intensification of summer precipitation trend over southern India are both linked to a deepening of JJAS surface pressure conditions over the Arabian Sea. We show that the model skills in reproducing this trends and patterns are significantly improved only when an increasing dust emission trend is imposed on the basis of observations. We conclude that although climate variability might primarily determine the observed regional pattern of increasing dust activity and precipitation during the 2000-2009 decade, the associated dust radiative forcing might however induce a critical dynamical feedback contributing to enhanced regional moisture convergence and JJAS precipitation over Southern India.

  7. Local school policies increase physical activity in Norwegian secondary schools

    PubMed Central

    Haug, Ellen; Torsheim, Torbjørn; Samdal, Oddrun

    2010-01-01

    SUMMARY The implementation of school policies to support the adoption of physical activity is one of the main strategies recommended to increase physical activity levels among this age group. However, documentation of the effect of such policies is so far limited. The purpose of this study was to explore policy-related practices to support physical activity in Norwegian secondary schools and their association with recess physical activity. Emphasis was given to examine the association between policies and physical activity, over and beyond, individual level interests and environmental factors and to examine cross-level interaction effects. This cross-sectional study was based on a nationally representative sample of Norwegian secondary schools and grade 8 students who participated in the Health Behaviour in School-aged Children (HBSC) 2005/06 study. The final sample comprised 68 schools and 1347 students. Data were collected through questionnaires. The results showed that schools with a written policy for physical activity and schools offering organized non-curricular physical activity several times a week had a higher proportion of students reporting daily participation in recess physical activity. Multilevel logistic regression analysis demonstrated a cross-level main effect of the policy index after controlling for sex, socio-economic status, individual-level interests and the physical environment. A significant contribution of adding the policy index to the prediction of recess physical activity above that provided by the individual-level interests and the physical environment was demonstrated. The results are encouraging and give scientific support to policy documents recommending the implementation of school policies to increase physical activity. PMID:19884244

  8. Changing the School Environment to Increase Physical Activity in Children

    PubMed Central

    Lanningham-Foster, Lorraine; Foster, Randal C.; McCrady, Shelly K.; Manohar, Chinmay; Jensen, Teresa B.; Mitre, Naim G.; Hill, James O.; Levine, James A.

    2009-01-01

    OBJECTIVE We examined the hypothesis that elementary school-age children will be more physically active while attending school in a novel, activity-permissive school environment compared to their traditional school environment RESEARCH METHODS AND PROCEDURES Twenty-four children were monitored with a single triaxial accelerometer worn on the thigh. The students attended school in three different environments: traditional school with chairs and desks, an activity-permissive environment, and finally their traditional school with desks which encouraged standing. Data from the school children was compared with another group of age-matched children (n = 16) whose physical activity was monitored during summer vacation. RESULTS When children attended school in their traditional environment, they moved an average (mean ± standard deviation) 71 ± 0.4 m/s2. When the children attended school in the activity-permissive environment, they moved an average of 115 ± 3 m/s2. The children moved 71 ± 0.7 m/s2 while attending the traditional school with standing desks. Children moved significantly more while attending school in the activity-permissive environment compared to the amount that they moved in either of the traditional school environments (P<0.0001 for both). Comparing children’s activity while they were on summer vacation (113 ± 8 m/s2) to school-bound children in their traditional environment showed significantly more activity for the children on summer vacation (P<0.0001). The school children in the activity-permissive environment were as active as children on summer vacation. DISCUSSION Children will move more in an activity-permissive environment. Strategies to increase the activity of school children may involve re-designing the school itself. PMID:18535550

  9. Using the Web to Increase Physical Activity in College Students

    ERIC Educational Resources Information Center

    Magoc, Dejan; Tomaka, Joe; Bridges-Arzaga, Amber

    2011-01-01

    Objectives: To evaluate the effectiveness of a theoretically based and Web-delivered intervention using common course technology for increasing physical activity in a college student sample. Methods: One hundred four students randomly participated in either a Web-based intervention involving 7 theory-based learning lessons or a control group that…

  10. Texting to increase adolescent physical activity: Feasibility assessment

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Feasibility trials assess whether a behavior change program warrants a definite trial evaluation. This paper reports the feasibility of an intervention consisting of Self Determination Theory-informed text messages, pedometers, and goal prompts to increase adolescent physical activity. A 4-group ran...

  11. Games for increasing physical activity: Mechanisms for change

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A small conference was held in Houston, TX, in May 2014, to address how to enhance exergames to increase physical activity. Several leading researchers were asked to address specific topics. Attendees came from across the globe. This Games for Health Journal Special Issue is devoted to sharing the a...

  12. Reduced Frontal Activation with Increasing 2nd Language Proficiency

    ERIC Educational Resources Information Center

    Stein, Maria; Federspiel, Andrea; Koenig, Thomas; Wirth, Miranka; Lehmann, Christoph; Wiest, Roland; Strik, Werner; Brandeis, Daniel; Dierks, Thomas

    2009-01-01

    The factors influencing the degree of separation or overlap in the neuronal networks responsible for the processing of first and second language are still subject to investigation. This longitudinal study investigates how increasing second language proficiency influences activation differences during lexico-semantic processing of first and second…

  13. Utilizing Wisconsin Afterschool Programs to Increase Physical Activity in Youth

    ERIC Educational Resources Information Center

    Cavanagh, Bradley D.; Meinen, Amy

    2015-01-01

    Background: Approximately 31.7% of children in the United States are overweight or obese. Interventions in the afterschool setting may help combat childhood obesity. Research exists on interventions in school settings, but a few data exist for interventions about afterschool programs. This study investigates increasing physical activity (PA) in…

  14. Hypocholesterolemia in chronic anemias with increased erythropoietic activity.

    PubMed

    Shalev, Hanna; Kapelushnik, Joseph; Moser, Asher; Knobler, Hilla; Tamary, Hannah

    2007-03-01

    Hypocholesterolemia of unknown etiology has been previously described in various chronic anemias. Few small studies also suggested that those patients have a lower incidence of atherosclerotic events. The aim of our study was to determine the extent of hypocholesterolemia in various types of anemias. We studied 59 patients with chronic anemias associated with high-erythropoietic activity (thalassemia intermedia, congenital dyserythropoietic anemia type I, congenital spherocytosis), 8 patients with low-erythropoietic activity anemias (acquired aplastic anemia, Fanconi anemia, and Diamond Blackfan anemia), and 20 healthy controls. Mean serum cholesterol, high-density lipoprotein (HDL) cholesterol, low-density lipoprotein (LDL) cholesterol, triglycerides, hemoglobin, serum ferritin, soluble transferrin receptor (STR), and serum erythropoietin levels were determined in each patient. All patients with chronic anemia and increased erythropoietic activity had hypocholesterolemia, whereas none of those with low erythropoietic activity was hypocholesterolemic. Mean serum cholesterol, HDL cholesterol, and LDL cholesterol levels were found to be significantly lower in the high-erythropoietic activity group (80+/-19 mg/dl; 31+/-10 mg/dl; 35+/-14 mg/dl, respectively) compared with the control group (P<0.001; 0.001; 0.001, respectively) and the low-erythropoietic activity group (P<0.001; 0.001; 0.01, respectively). Significant inverse correlation (R2=0.507) was observed between serum cholesterol and STR levels, which in the absence of iron deficiency reflect bone marrow activity. Taken together, our results imply that hypocholesterolemia accompanies anemias with high-erythropoietic activity. We suggest that the high-erythropoitic activity-associated hypocholesterolemia is due to increased cholesterol requirements by the proliferating erythoid cells. Further studies are needed to elucidate the exact mechanism and the possible clinical consequences of this phenomenon. PMID

  15. Increased matriptase zymogen activation in inflammatory skin disorders

    PubMed Central

    Chen, Cheng-Jueng; Wu, Bai-Yao; Tsao, Pai-In; Chen, Chi-Yung; Wu, Mei-Hsuan; Chan, Yee Lam E.; Lee, Herng-Sheng; Johnson, Michael D.; Eckert, Richard L.; Chen, Ya-Wen; Chou, Fengpai; Lin, Chen-Yong

    2011-01-01

    Matriptase, a type 2 transmembrane serine protease, and its inhibitor hepatocyte growth factor activator inhibitor (HAI)-1 are required for normal epidermal barrier function, and matriptase activity is tightly regulated during this process. We therefore hypothesized that this protease system might be deregulated in skin disease. To test this, we examined the level and activation state of matriptase in examples of 23 human skin disorders. We first examined matriptase and HAI-1 protein distribution in normal epidermis. Matriptase was detected at high levels at cell-cell junctions in the basal layer and spinous layers but was present at minimal levels in the granular layer. HAI-1 was distributed in a similar pattern, except that high-level expression was retained in the granular layer. This pattern of expression was retained in most skin disorders. We next examined the distribution of activated matriptase. Although activated matriptase is not detected in normal epidermis, a dramatic increase is seen in keratinocytes at the site of inflammation in 16 different skin diseases. To gain further evidence that activation is associated with inflammatory stimuli, we challenged HaCaT cells with acidic pH or H2O2 and observed matriptase activation. These findings suggest that inflammation-associated reactive oxygen species and tissue acidity may enhance matriptase activation in some skin diseases. PMID:21123732

  16. Methods of increasing secretion of polypeptides having biological activity

    DOEpatents

    Merino, Sandra

    2013-10-01

    The present invention relates to methods for producing a secreted polypeptide having biological activity, comprising: (a) transforming a fungal host cell with a fusion protein construct encoding a fusion protein, which comprises: (i) a first polynucleotide encoding a signal peptide; (ii) a second polynucleotide encoding at least a catalytic domain of an endoglucanase or a portion thereof; and (iii) a third polynucleotide encoding at least a catalytic domain of a polypeptide having biological activity; wherein the signal peptide and at least the catalytic domain of the endoglucanase increases secretion of the polypeptide having biological activity compared to the absence of at least the catalytic domain of the endoglucanase; (b) cultivating the transformed fungal host cell under conditions suitable for production of the fusion protein; and (c) recovering the fusion protein, a component thereof, or a combination thereof, having biological activity, from the cultivation medium.

  17. Methods of increasing secretion of polypeptides having biological activity

    DOEpatents

    Merino, Sandra

    2014-05-27

    The present invention relates to methods for producing a secreted polypeptide having biological activity, comprising: (a) transforming a fungal host cell with a fusion protein construct encoding a fusion protein, which comprises: (i) a first polynucleotide encoding a signal peptide; (ii) a second polynucleotide encoding at least a catalytic domain of an endoglucanase or a portion thereof; and (iii) a third polynucleotide encoding at least a catalytic domain of a polypeptide having biological activity; wherein the signal peptide and at least the catalytic domain of the endoglucanase increases secretion of the polypeptide having biological activity compared to the absence of at least the catalytic domain of the endoglucanase; (b) cultivating the transformed fungal host cell under conditions suitable for production of the fusion protein; and (c) recovering the fusion protein, a component thereof, or a combination thereof, having biological activity, from the cultivation medium.

  18. Methods of increasing secretion of polypeptides having biological activity

    SciTech Connect

    Merino, Sandra

    2014-10-28

    The present invention relates to methods for producing a secreted polypeptide having biological activity, comprising: (a) transforming a fungal host cell with a fusion protein construct encoding a fusion protein, which comprises: (i) a first polynucleotide encoding a signal peptide; (ii) a second polynucleotide encoding at least a catalytic domain of an endoglucanase or a portion thereof; and (iii) a third polynucleotide encoding at least a catalytic domain of a polypeptide having biological activity; wherein the signal peptide and at least the catalytic domain of the endoglucanase increases secretion of the polypeptide having biological activity compared to the absence of at least the catalytic domain of the endoglucanase; (b) cultivating the transformed fungal host cell under conditions suitable for production of the fusion protein; and (c) recovering the fusion protein, a component thereof, or a combination thereof, having biological activity, from the cultivation medium.

  19. Methods of increasing secretion of polypeptides having biological activity

    SciTech Connect

    Merino, Sandra

    2015-04-14

    The present invention relates to methods for producing a secreted polypeptide having biological activity, comprising: (a) transforming a fungal host cell with a fusion protein construct encoding a fusion protein, which comprises: (i) a first polynucleotide encoding a signal peptide; (ii) a second polynucleotide encoding at least a catalytic domain of an endoglucanase or a portion thereof; and (iii) a third polynucleotide encoding at least a catalytic domain of a polypeptide having biological activity; wherein the signal peptide and at least the catalytic domain of the endoglucanase increases secretion of the polypeptide having biological activity compared to the absence of at least the catalytic domain of the endoglucanase; (b) cultivating the transformed fungal host cell under conditions suitable for production of the fusion protein; and (c) recovering the fusion protein, a component thereof, or a combination thereof, having biological activity, from the cultivation medium.

  20. Plant species richness increases phosphatase activities in an experimental grassland

    NASA Astrophysics Data System (ADS)

    Hacker, Nina; Wilcke, Wolfgang; Oelmann, Yvonne

    2014-05-01

    Plant species richness has been shown to increase aboveground nutrient uptake requiring the mobilization of soil nutrient pools. For phosphorus (P) the underlying mechanisms for increased P release in soil under highly diverse grassland mixtures remain obscure because aboveground P storage and concentrations of inorganic and organic P in soil solution and differently reactive soil P pools are unrelated (Oelmann et al. 2011). The need of plants and soil microorganisms for P can increase the exudation of enzymes hydrolyzing organically bound P (phosphatases) which might represent an important release mechanism of inorganic P in a competitive environment such as highly diverse grassland mixtures. Our objectives were to test the effects of i) plant functional groups (legumes, grasses, non-leguminous tall and small herbs), and of (ii) plant species richness on microbial P (Pmic) and phosphatase activities in soil. In autumn 2013, we measured Pmic and alkaline phosphomonoesterase and phosphodiesterase activities in soil of 80 grassland mixtures comprising different community compositions and species richness (1, 2, 4, 8, 16, 60) in the Jena Experiment. In general, Pmic and enzyme activities were correlated (r = 0.59 and 0.46 for phosphomonoesterase and phosphodiesterase activities, respectively; p

  1. Increases and fluctuations in thermal activity at Mount Wrangell, Alaska

    SciTech Connect

    Motyka, R.J.

    1983-01-01

    The objectives of this study were to document and interpret changes in thermal activity at two of three craters located on the rim of the ice-filled summit caldera of Mount Wrangell, an active glacier-clad shield volcano in south-central Alaska. The technique of glacier calorimetry was developed, through which changes in the volume of glacier ice in the craters and caldera were measured and related to changes in heat flow. Chemical analysis of gases and acid-thermal waters provided information on the underlying heat source. In 1965, thermal activity began increasing at both the North and West Craters. During the ensuing years, heat flow increased significantly at the North Crater, although in a highly fluctuating manner, while gradually declining at the West Crater. Pulses in heat flow at the North Crater occurred in 1966-68 and 1972-74, with both pulses followed by a four year decline in activity. Increases in heat flow began again in 1978-79 and have continued unabated through the summer of 1983. Over 80% of the 4.4 x 10/sup 7/m/sup 3/ ice volume within the crater in 1966 was melted by 1982, and the meltwaters have drained or evaporated from the crater. The subsequent rapid development of numerous fumaroles, the large dry-gas proportion of SO/sub 2/ (27%), and the inferred presence of gaseous HCl indicate that a shallow degassing magma body is the source of heat driving the thermal system. Seismically induced fracturing above the magma body is hypothesized to explain the initial increases in thermal activity.

  2. Increasing Arabian dust activity and the Indian summer monsoon

    NASA Astrophysics Data System (ADS)

    Solmon, F.; Nair, V. S.; Mallet, M.

    2015-07-01

    Over the past decade, aerosol optical depth (AOD) observations based on satellite and ground measurements have shown a significant increase over Arabia and the Arabian Sea, attributed to an intensification of regional dust activity. Recent studies have also suggested that west Asian dust forcing could induce a positive response of Indian monsoon precipitations on a weekly timescale. Using observations and a regional climate model including interactive slab-ocean and dust aerosol schemes, the present study investigates possible climatic links between the increasing June-July-August-September (JJAS) Arabian dust activity and precipitation trends over southern India during the 2000-2009 decade. Meteorological reanalysis and AOD observations suggest that the observed decadal increase of dust activity and a simultaneous intensification of summer precipitation trend over southern India are both linked to a deepening of JJAS surface pressure conditions over the Arabian Sea. In the first part of the study, we analyze the mean climate response to dust radiative forcing over the domain, discussing notably the relative role of Arabian vs. Indo-Pakistani dust regions. In the second part of the study, we show that the model skills in reproducing regional dynamical patterns and southern Indian precipitation trends are significantly improved only when an increasing dust emission trend is imposed on the basis of observations. We conclude that although interannual climate variability might primarily determine the observed regional pattern of increasing dust activity and precipitation during the 2000-2009 decade, the associated dust radiative forcing might in return induce a critical dynamical feedback contributing to enhancing regional moisture convergence and JJAS precipitations over southern India.

  3. Plant diversity increases soil microbial activity and soil carbon storage.

    PubMed

    Lange, Markus; Eisenhauer, Nico; Sierra, Carlos A; Bessler, Holger; Engels, Christoph; Griffiths, Robert I; Mellado-Vázquez, Perla G; Malik, Ashish A; Roy, Jacques; Scheu, Stefan; Steinbeiss, Sibylle; Thomson, Bruce C; Trumbore, Susan E; Gleixner, Gerd

    2015-01-01

    Plant diversity strongly influences ecosystem functions and services, such as soil carbon storage. However, the mechanisms underlying the positive plant diversity effects on soil carbon storage are poorly understood. We explored this relationship using long-term data from a grassland biodiversity experiment (The Jena Experiment) and radiocarbon ((14)C) modelling. Here we show that higher plant diversity increases rhizosphere carbon inputs into the microbial community resulting in both increased microbial activity and carbon storage. Increases in soil carbon were related to the enhanced accumulation of recently fixed carbon in high-diversity plots, while plant diversity had less pronounced effects on the decomposition rate of existing carbon. The present study shows that elevated carbon storage at high plant diversity is a direct function of the soil microbial community, indicating that the increase in carbon storage is mainly limited by the integration of new carbon into soil and less by the decomposition of existing soil carbon. PMID:25848862

  4. Active learning increases student performance in science, engineering, and mathematics.

    PubMed

    Freeman, Scott; Eddy, Sarah L; McDonough, Miles; Smith, Michelle K; Okoroafor, Nnadozie; Jordt, Hannah; Wenderoth, Mary Pat

    2014-06-10

    To test the hypothesis that lecturing maximizes learning and course performance, we metaanalyzed 225 studies that reported data on examination scores or failure rates when comparing student performance in undergraduate science, technology, engineering, and mathematics (STEM) courses under traditional lecturing versus active learning. The effect sizes indicate that on average, student performance on examinations and concept inventories increased by 0.47 SDs under active learning (n = 158 studies), and that the odds ratio for failing was 1.95 under traditional lecturing (n = 67 studies). These results indicate that average examination scores improved by about 6% in active learning sections, and that students in classes with traditional lecturing were 1.5 times more likely to fail than were students in classes with active learning. Heterogeneity analyses indicated that both results hold across the STEM disciplines, that active learning increases scores on concept inventories more than on course examinations, and that active learning appears effective across all class sizes--although the greatest effects are in small (n ≤ 50) classes. Trim and fill analyses and fail-safe n calculations suggest that the results are not due to publication bias. The results also appear robust to variation in the methodological rigor of the included studies, based on the quality of controls over student quality and instructor identity. This is the largest and most comprehensive metaanalysis of undergraduate STEM education published to date. The results raise questions about the continued use of traditional lecturing as a control in research studies, and support active learning as the preferred, empirically validated teaching practice in regular classrooms. PMID:24821756

  5. Active learning increases student performance in science, engineering, and mathematics

    PubMed Central

    Freeman, Scott; Eddy, Sarah L.; McDonough, Miles; Smith, Michelle K.; Okoroafor, Nnadozie; Jordt, Hannah; Wenderoth, Mary Pat

    2014-01-01

    To test the hypothesis that lecturing maximizes learning and course performance, we metaanalyzed 225 studies that reported data on examination scores or failure rates when comparing student performance in undergraduate science, technology, engineering, and mathematics (STEM) courses under traditional lecturing versus active learning. The effect sizes indicate that on average, student performance on examinations and concept inventories increased by 0.47 SDs under active learning (n = 158 studies), and that the odds ratio for failing was 1.95 under traditional lecturing (n = 67 studies). These results indicate that average examination scores improved by about 6% in active learning sections, and that students in classes with traditional lecturing were 1.5 times more likely to fail than were students in classes with active learning. Heterogeneity analyses indicated that both results hold across the STEM disciplines, that active learning increases scores on concept inventories more than on course examinations, and that active learning appears effective across all class sizes—although the greatest effects are in small (n ≤ 50) classes. Trim and fill analyses and fail-safe n calculations suggest that the results are not due to publication bias. The results also appear robust to variation in the methodological rigor of the included studies, based on the quality of controls over student quality and instructor identity. This is the largest and most comprehensive metaanalysis of undergraduate STEM education published to date. The results raise questions about the continued use of traditional lecturing as a control in research studies, and support active learning as the preferred, empirically validated teaching practice in regular classrooms. PMID:24821756

  6. An active loudness model suggesting tinnitus as increased central noise and hyperacusis as increased nonlinear gain

    PubMed Central

    Zeng, Fan-Gang

    2012-01-01

    The present study uses a systems engineering approach to delineate the relationship between tinnitus and hyperacusis as a result of either hearing loss in the ear or an imbalanced state in the brain. Specifically examined is the input–output function, or loudness growth as a function of intensity in both normal and pathological conditions. Tinnitus reduces the output dynamic range by raising the floor, while hyperacusis reduces the input dynamic range by lowering the ceiling or sound tolerance level. Tinnitus does not necessarily steepen the loudness growth function but hyperacusis always does. An active loudness model that consists of an expansion stage following a compression stage can account for these key properties in tinnitus and hyperacusis loudness functions. The active loudness model suggests that tinnitus is a result of increased central noise, while hyperacusis is due to increased nonlinear gain. The active loudness model also generates specific predictions on loudness growth in tinnitus, hyperacusis, hearing loss or any combinations of the three conditions. These predictions need to be verified by experimental data and have explicit implications for treatment of tinnitus and hyperacusis. PMID:22641191

  7. JAK-2 V617F mutation increases heparanase procoagulant activity.

    PubMed

    Kogan, Inna; Chap, Dafna; Hoffman, Ron; Axelman, Elena; Brenner, Benjamin; Nadir, Yona

    2016-01-01

    Patients with polycythaemia vera (PV), essential thrombocythaemia (ET) and primary myelofibrosis (PMF) are at increased risk of arterial and venous thrombosis. In patients with ET a positive correlation was observed between JAK-2 V617F mutation, that facilitates erythropoietin receptor signalling, and thrombotic events, although the mechanism involved is not clear. We previously demonstrated that heparanase protein forms a complex and enhances the activity of the blood coagulation initiator tissue factor (TF) which leads to increased factor Xa production and subsequent activation of the coagulation system. The present study was aimed to evaluate heparanase procoagulant activity in myeloproliferative neoplasms. Forty bone marrow biopsies of patients with ET, PV, PMF and chronic myelogenous leukaemia (CML) were immunostained to heparanase, TF and TF pathway inhibitor (TFPI). Erythropoietin receptor positive cell lines U87 human glioma and MCF-7 human breast carcinoma were studied. Heparanase and TFPI staining were more prominent in ET, PV and PMF compared to CML. The strongest staining was in JAK-2 positive ET biopsies. Heparanase level and procoagulant activity were higher in U87 cells transfected to over express JAK-2 V617F mutation compared to control and the effect was reversed using JAK-2 inhibitors (Ruxolitinib, VZ3) and hydroxyurea, although the latter drug did not inhibit JAK-2 phosphorylation. Erythropoietin increased while JAK-2 inhibitors decreased the heparanase level and procoagulant activity in U87 and MCF-7 parental cells. In conclusion, JAK-2 is involved in heparanase up-regulation via the erythropoietin receptor. The present findings may potentially point to a new mechanism of thrombosis in JAK-2 positive ET patients. PMID:26489695

  8. Can nursing students' confidence levels increase with repeated simulation activities?

    PubMed

    Cummings, Cynthia L; Connelly, Linda K

    2016-01-01

    In 2014, nursing faculty conducted a study with undergraduate nursing students on their satisfaction, confidence, and educational practice levels, as it related to simulation activities throughout the curriculum. The study was a voluntary survey conducted on junior and senior year nursing students. It consisted of 30 items based on the Student Satisfaction and Self-Confidence in Learning and the Educational Practices Questionnaire (Jeffries, 2012). Mean averages were obtained for each of the 30 items from both groups and were compared using T scores for unpaired means. The results showed that 8 of the items had a 95% confidence level and when combined the items were significant for p <.001. The items identified were those related to self-confidence and active learning. Based on these findings, it can be assumed that repeated simulation experiences can lead to an increase in student confidence and active learning. PMID:26599594

  9. Interactions Increase Forager Availability and Activity in Harvester Ants

    PubMed Central

    Pinter-Wollman, Noa; Crow, Sam; Allen, Kelsey; Mathur, Maya B.; Gordon, Deborah M.

    2015-01-01

    Social insect colonies use interactions among workers to regulate collective behavior. Harvester ant foragers interact in a chamber just inside the nest entrance, here called the 'entrance chamber'. Previous studies of the activation of foragers in red harvester ants show that an outgoing forager inside the nest experiences an increase in brief antennal contacts before it leaves the nest to forage. Here we compare the interaction rate experienced by foragers that left the nest and ants that did not. We found that ants in the entrance chamber that leave the nest to forage experienced more interactions than ants that descend to the deeper nest without foraging. Additionally, we found that the availability of foragers in the entrance chamber is associated with the rate of forager return. An increase in the rate of forager return leads to an increase in the rate at which ants descend to the deeper nest, which then stimulates more ants to ascend into the entrance chamber. Thus a higher rate of forager return leads to more available foragers in the entrance chamber. The highest density of interactions occurs near the nest entrance and the entrances of the tunnels from the entrance chamber to the deeper nest. Local interactions with returning foragers regulate both the activation of waiting foragers and the number of foragers available to be activated. PMID:26539724

  10. Interactions Increase Forager Availability and Activity in Harvester Ants.

    PubMed

    Pless, Evlyn; Queirolo, Jovel; Pinter-Wollman, Noa; Crow, Sam; Allen, Kelsey; Mathur, Maya B; Gordon, Deborah M

    2015-01-01

    Social insect colonies use interactions among workers to regulate collective behavior. Harvester ant foragers interact in a chamber just inside the nest entrance, here called the 'entrance chamber'. Previous studies of the activation of foragers in red harvester ants show that an outgoing forager inside the nest experiences an increase in brief antennal contacts before it leaves the nest to forage. Here we compare the interaction rate experienced by foragers that left the nest and ants that did not. We found that ants in the entrance chamber that leave the nest to forage experienced more interactions than ants that descend to the deeper nest without foraging. Additionally, we found that the availability of foragers in the entrance chamber is associated with the rate of forager return. An increase in the rate of forager return leads to an increase in the rate at which ants descend to the deeper nest, which then stimulates more ants to ascend into the entrance chamber. Thus a higher rate of forager return leads to more available foragers in the entrance chamber. The highest density of interactions occurs near the nest entrance and the entrances of the tunnels from the entrance chamber to the deeper nest. Local interactions with returning foragers regulate both the activation of waiting foragers and the number of foragers available to be activated. PMID:26539724

  11. 5-Lipoxygenase Activity Increases Susceptibility to Experimental Paracoccidioides brasiliensis Infection

    PubMed Central

    Tristão, Fabrine Sales Massafera; Rocha, Fernanda Agostini; Moreira, Ana Paula; Cunha, Fernando Queiroz; Rossi, Marcos Antonio

    2013-01-01

    Paracoccidioidomycosis (PCM) is a systemic mycosis caused by the thermodimorphic fungus Paracoccidioides brasiliensis. Leukotrienes and lipoxins are lipid mediators produced after 5-lipoxygenase (5-LO) activation that exhibit pro- and anti-inflammatory roles, respectively. Here, we have investigated the contribution of 5-LO enzymatic activity in PCM using an experimental model of P. brasiliensis infection. B6.129 wild-type (B6.129) and 5-LO-deficient (5-LO−/−) mice were intravenously inoculated with a virulent strain of P. brasiliensis (Pb18), and the survival rate of the infected mice was investigated on different days after yeast infection. 5-LO−/− mice exhibited an increased survival rate associated with a decreased number of CFU. The resistance of 5-LO−/− during PCM was associated with augmented nitric oxide (NO) production and the formation of compact granulomas. In addition, the absence of 5-LO was associated with a diminished number of CD4+ CD25+ regulatory T cells, higher levels of gamma interferon and interleukin-12, and increased T-bet (a T-box transcription factor that directs Th1 lineage commitment) mRNA levels in the lungs. Taken together, our results show for the first time that 5-LO enzymatic activity increases susceptibility to P. brasiliensis, suggesting that this pathway may be a potential target for therapeutic intervention during PCM. PMID:23381993

  12. Projecting climate-driven increases in North American fire activity

    NASA Astrophysics Data System (ADS)

    Wang, D.; Morton, D. C.; Collatz, G. J.

    2013-12-01

    Climate regulates fire activity through controls on vegetation productivity (fuels), lightning ignitions, and conditions governing fire spread. In many regions of the world, human management also influences the timing, duration, and extent of fire activity. These coupled interactions between human and natural systems make fire a complex component of the Earth system. Satellite data provide valuable information on the spatial and temporal dynamics of recent fire activity, as active fires, burned area, and land cover information can be combined to separate wildfires from intentional burning for agriculture and forestry. Here, we combined satellite-derived burned area data with land cover and climate data to assess fire-climate relationships in North America between 2000-2012. We used the latest versions of the Global Fire Emissions Database (GFED) burned area product and Modern-Era Retrospective Analysis for Research and Applications (MERRA) climate data to develop regional relationships between burned area and potential evaporation (PE), an integrated dryness metric. Logistic regression models were developed to link burned area with PE and individual climate variables during and preceding the fire season, and optimal models were selected based on Akaike Information Criterion (AIC). Overall, our model explained 85% of the variance in burned area since 2000 across North America. Fire-climate relationships from the era of satellite observations provide a blueprint for potential changes in fire activity under scenarios of climate change. We used that blueprint to evaluate potential changes in fire activity over the next 50 years based on twenty models from the Coupled Model Intercomparison Project Phase 5 (CMIP5). All models suggest an increase of PE under low and high emissions scenarios (Representative Concentration Pathways (RCP) 4.5 and 8.5, respectively), with largest increases in projected burned area across the western US and central Canada. Overall, near

  13. Changes in baseball batters' brain activity with increased pitch choice.

    PubMed

    Ryu, Kwangmin; Kim, Jingu; Ali, Asif; Kim, Woojong; Radlo, Steven J

    2015-09-01

    In baseball, one factor necessary for batters to decide whether to swing or not depends on what type of pitch is thrown. Oftentimes batters will look for their pitch (i.e., waiting for a fastball). In general, when a pitcher has many types of pitches in his arsenal, batters will have greater difficulty deciding upon the pitch thrown. Little research has been investigated the psychophysiology of a batters decision-making processes. Therefore, the primary purpose of this study was to determine how brain activation changes according to an increase in the number of alternatives (NA) available. A total of 15 male college baseball players participated in this study. The stimuli used in this experiment were video clips of a right-handed pitcher throwing fastball, curve, and slider pitches. The task was to press a button after selecting the fastball as the target stimulus from two pitch choices (fastball and curve), and then from three possibilities (fastball, curve, and slider). Functional and anatomic image scanning magnetic resonance imaging (MRI) runs took 4 and 5[Formula: see text]min, respectively. According to our analysis, the right precentral gyrus, left medial frontal gyrus, and right fusiform gyrus were activated when the NA was one. The supplementary motor areas (SMA) and primary motor cortex were activated when there were two alternatives to choose from and the inferior orbitofrontal gyrus was specifically activated with three alternatives. Contrary to our expectations, the NA was not a critical factor influencing the activation of related decision making areas when the NA was compared against one another. These findings highlight that specific brain areas related to decision making were activated as the NA increased. PMID:26227537

  14. Serotonin increases synaptic activity in olfactory bulb glomeruli.

    PubMed

    Brill, Julia; Shao, Zuoyi; Puche, Adam C; Wachowiak, Matt; Shipley, Michael T

    2016-03-01

    Serotoninergic fibers densely innervate olfactory bulb glomeruli, the first sites of synaptic integration in the olfactory system. Acting through 5HT2A receptors, serotonin (5HT) directly excites external tufted cells (ETCs), key excitatory glomerular neurons, and depolarizes some mitral cells (MCs), the olfactory bulb's main output neurons. We further investigated 5HT action on MCs and determined its effects on the two major classes of glomerular interneurons: GABAergic/dopaminergic short axon cells (SACs) and GABAergic periglomerular cells (PGCs). In SACs, 5HT evoked a depolarizing current mediated by 5HT2C receptors but did not significantly impact spike rate. 5HT had no measurable direct effect in PGCs. Serotonin increased spontaneous excitatory and inhibitory postsynaptic currents (sEPSCs and sIPSCs) in PGCs and SACs. Increased sEPSCs were mediated by 5HT2A receptors, suggesting that they are primarily due to enhanced excitatory drive from ETCs. Increased sIPSCs resulted from elevated excitatory drive onto GABAergic interneurons and augmented GABA release from SACs. Serotonin-mediated GABA release from SACs was action potential independent and significantly increased miniature IPSC frequency in glomerular neurons. When focally applied to a glomerulus, 5HT increased MC spontaneous firing greater than twofold but did not increase olfactory nerve-evoked responses. Taken together, 5HT modulates glomerular network activity in several ways: 1) it increases ETC-mediated feed-forward excitation onto MCs, SACs, and PGCs; 2) it increases inhibition of glomerular interneurons; 3) it directly triggers action potential-independent GABA release from SACs; and 4) these network actions increase spontaneous MC firing without enhancing responses to suprathreshold sensory input. This may enhance MC sensitivity while maintaining dynamic range. PMID:26655822

  15. Silencing of PKCη induces cycle arrest of EBV(+) B lymphoma cells by upregulating expression of p38-MAPK/TAp73/GADD45α and increases susceptibility to chemotherapeutic agents.

    PubMed

    Park, Ga Bin; Choi, Yunock; Kim, Yeong-Seok; Lee, Hyun-Kyung; Kim, Daejin; Hur, Dae Young

    2014-08-01

    PKCη is involved in proliferation, differentiation, and drug resistance. However, PKCη function in EBV(+) B lymphoma remains poorly understood. Gene silencing of PKCη through siRNA knockdown inhibited cellular proliferation, induced cell cycle arrest in G0/G1 and G2/M phases, and sensitized cells to chemotherapeutic drugs. Upon PKCη knockdown, expression levels of p21, GADD45α, and TAp73 were all increased, whereas expression levels of CDK2, CDK4, CDK6, cyclin E, cyclin B1, and cdc2 were all downregulated. PKCη silencing also activated p38-MAPK, which in turn contributed to the expression of cell cycle arrest-related molecules. These results suggest that siRNA-mediated silencing of PKCη can be a potent tool to complement existing chemotherapy regimens for treating EBV(+) B lymphoma. PMID:24784886

  16. Increasing Children's Physical Activity During the School Day.

    PubMed

    Hatfield, Daniel Philip; Chomitz, Virginia Rall

    2015-06-01

    Insufficient levels of daily physical activity (PA) among children in the USA and worldwide have profound implications for pediatric obesity and children's health and well-being more generally. Public health recommendations highlight the central role that schools play in providing equitable opportunities for PA for all children. This review identifies evidence-based approaches for increasing children's PA throughout the school day and discusses multilevel factors that support implementation of such approaches. Opportunities to increase school-day PA span not only in-school time (e.g., quality recess and physical education, classroom activity breaks) but also time before school (e.g., active commuting initiatives) and after school (e.g., intramural and interscholastic sports programs). For such approaches to impact children's PA, dimensions of implementation such as adoption, fidelity, penetration, implementation costs, and sustainability are critical. Multilevel factors that influence implementation include policies, school environment and organizational factors, teacher and classroom factors, child and family characteristics, and attributes of the PA approach itself. Research and field observations reinforce the importance of understanding challenges specific to working with schools, including multiple stakeholders, competing priorities, limited facilities and staff capacity, and heterogeneity of students. Thus, while schools hold promise as promoters and equalizers of PA engagement for all children, more research is needed on the levers that influence implementation of effective school-based PA policies and programs. PMID:26627212

  17. Betaine increases the butyrylcholinesterase activity in rat plasma.

    PubMed

    Šišková, K; Dubničková, M; Pašková, Ľ; Rajdl, D; Ďuračková, Z; Muchová, J; Pauliková, I; Racek, J

    2016-03-14

    The physiological function of butyrylcholinesterase (EC 3.1.1.8, BChE) is not clearly understood, but a role was suggested in the fat utilization process, resulting in positive correlation between plasma triglyceride (TG) levels and BChE activity. Consequently we tested the hypothesis that regular intake of betaine, a natural compound intervening in the liver TG metabolism could influence the BChE activity. The BChE activity was estimated spectrophotometrically in plasma of rats fed with betaine enriched standard (B) or high-fat diet (HFB). The results confirmed decreased TG plasma levels after betaine treatment independently on the type of diet (0.15+/-0.03 (B) vs. 0.27+/-0.08 (control) mmol/l; p=0.003 and 0.13+/-0.03 (HFB) vs. 0.27+/-0.08 (control) mmol/l; p=0.005). The BChE activity increased significantly with betaine administration, however the change was more distinct in the HFB group (0.84+/-0.34 (HFB) vs. 0.22+/-0.04 (control) O.D./min/mg; p<0.001 and 0.41+/-0.11 (B) vs. 0.22+/-0.04 (control) O.D./min/mg; p=0.001). In conclusion, betaine intake led to elevated BChE activity in plasma and this effect was potentiated by the HF diet. Since betaine is in general used as a supplement in the treatment of liver diseases accompanied by TG overload, its impact on the BChE activity in the role of the liver function marker should be taken into account. PMID:26596326

  18. Obstruction increases activation in the right inferior frontal gyrus.

    PubMed

    Liu, Tao; Saito, Hirofumi; Oi, Misato

    2016-08-01

    The right inferior frontal gyrus (IFG) is involved in intention understanding during interpersonal interactions. To examine how prior experience of cooperation and competition affects one's right IFG activation in the subsequent interaction, using near-infrared spectroscopy (NIRS) we simultaneously measured paired participants' bilateral IFG activations during a turn-taking game. Participant pairs were assigned to either one of two roles: a Builder taking the initial move to copy a target disk-pattern on monitor and the Partner taking the second move to aid in (cooperation) or to obstruct (competition) the Builder. The experiment consisted of two sessions. One participant (B-P) played as a Builder (B-) in session 1 and changed the role to the Partner (-P) in session 2, and vice versa for the paired participant (P-B). NIRS data in competition demonstrated that the Builder (B-) being obstructed in session 1 showed higher right IFG activation when (s)he took a role of obstructor (-P) in session 2 (the obstructed effect), whereas "the cooperated effect" was not revealed in cooperation. These results suggest that prior experience of being obstructed may facilitate understanding of the Builder and/or the obstructor's tactical move, thereby increasing his/her right IFG activation when one is meant to obstruct in subsequent competitions. PMID:26366676

  19. Increased Plasminogen Activator (Urokinase) in Tissue Culture After Fibrin Deposition

    PubMed Central

    Bernik, Maria B.

    1973-01-01

    Lysis of fibrin in tissue culture has been shown to be due to plasminogen activator identified immunologically as urokinase. The present study examines fibrinolytic events in culture, particularly mechanisms leading to increased urokinase levels and accelerated fibrinolysis. Deposition of fibrin on cells in culture was followed by a two- to six-fold increase in urokinase in the supernates and rapid disappearance of the fibrin. Investigation of factors that might be responsible for these events (including fibrin, fibrinogen, vasoactive stimuli, and the enzymes thrombin and plasmin) indicated that the enhanced urokinase yields were mediated through plasmin and thrombin. Study of the possible modes of action of thrombin and plasmin indicated that these enzymes are capable of acting on the cells themselves as well as on cell-produced material. The effect on cells was manifested by mitotic activity or, occasionally, cell injury and death. Although these effects influenced urokinase levels, enhanced yields were explained best by the action of enzymes on cellproduced material. Studies with plasmin and thrombin, and also trypsin, indicated that proteolytic enzymes may act in various ways—affect the stability of urokinase, interfere with inhibition of urokinase by naturally occurring inhibitor(s), and induce urokinase activity from inactive material. Plasma and thrombin appeared to act primarily through the latter mechanism. Inactive material, which gave rise to urokinase upon exposure to proteolytic enzymes and which may represent urokinase precursor, was found in cultures of kidney, lung, spleen, and thyroid. Urokinase in such inactive state appears to be readily accessible to activation by enzymes, particularly plasmin and thrombin, thus facilitating removal of fibrin and possibly also providing pathways to excessive fibrinolysis. PMID:4266421

  20. Both novelty and expertise increase action observation network activity

    PubMed Central

    Liew, Sook-Lei; Sheng, Tong; Margetis, John L.; Aziz-Zadeh, Lisa

    2013-01-01

    Our experiences with others affect how we perceive their actions. In particular, activity in bilateral premotor and parietal cortices during action observation, collectively known as the action observation network (AON), is modulated by one's expertise with the observed actions or individuals. However, conflicting reports suggest that AON activity is greatest both for familiar and unfamiliar actions. The current study examines the effects of different types and amounts of experience (e.g., visual, interpersonal, personal) on AON activation. fMRI was used to scan 16 healthy participants without prior experience with individuals with amputations (novices), 11 experienced occupational therapists (OTs) who had varying amounts of experience with individuals with amputations, and one individual born with below-elbow residual limbs (participant CJ), as they viewed video clips of goal-matched actions performed by an individual with residual limbs and by an individual with hands. Participants were given increased visual exposure to actions performed by both effectors midway through the scanning procedure. Novices demonstrated a large AON response to the initial viewing of an individual with residual limbs compared to one with hands, but this signal was attenuated after they received visual exposure to both effectors. In contrast, OTs, who had moderate familiarity with residual limbs, demonstrated a lower AON response upon initial viewing—similar to novices after they received visual exposure. At the other extreme, CJ, who has extreme familiarity with residual limbs both visually and motorically, shows a largely increased left-lateralized AON response, exceeding that of novices and experienced OTs, when viewing the residual limb compared to hand actions. These results suggest that a nuanced model of AON engagement is needed to explain how cases of both extreme experience (CJ) and extreme novelty (novices) can result in the greatest AON activity. PMID:24062656

  1. Building a Better Mousetrap (Exergame) to Increase Youth Physical Activity.

    PubMed

    Baranowski, Tom; Maddison, Ralph; Maloney, Ann; Medina, Ernie; Simons, Monique

    2014-04-01

    Although exergames have been demonstrated to induce moderate levels of physical activity (PA) if played as designed, there is conflicting evidence on use of exergaming leading to increased habitual PA. Exergames have increased PA in some home and school studies, but not others. Exergames have been used in community centers to good effect, but this has not generally been validated with research. PA from exergames may be enhanced by innovative use of sensors, "fun"-enhancing procedures, tailored messaging, message framing, story or narrative, goal setting, feedback, and values-based messaging. Research is needed on PA-enhancing procedures used within exergames for youth to provide a firmer foundation for the design and use of exergames in the future. PMID:26196047

  2. Increased serum cortisol binding in chronic active hepatitis

    SciTech Connect

    Orbach, O.; Schussler, G.C.

    1989-01-01

    A high serum cortisol concentration, apparently due to increased cortisol-binding globulin (CBG), was found in a patient (index case) with chronic active hepatitis (CAH). We therefore performed further studies to determine whether increased cortisol binding is generally associated with CAH. Serum samples were obtained from 15 hospitalized patients with long-term liver function test elevations but no evidence of cirrhosis, 15 normal subjects without a history of hepatitis, four healthy pregnant women, and 10 alcoholic patients with stigmata of cirrhosis. Serum cortisol binding was measured by an adaptation of a previously described charcoal uptake method. Thyroxine-binding globulin (TBG) and sex hormone-binding globulin were determined by radioimmunoassays. Charcoal uptake of 125I cortisol from sera of normal subjects and additional patients with CAH revealed that increased serum cortisol binding by a saturable site, presumably CBG, was associated with CAH. Cortisol binding was significantly correlated with immunoassayable TBG, suggesting that in CAH, similar mechanisms may be responsible for increasing the serum concentrations of CBG and TBG.

  3. Dopamine Receptor Activation Increases HIV Entry into Primary Human Macrophages

    PubMed Central

    Gaskill, Peter J.; Yano, Hideaki H.; Kalpana, Ganjam V.; Javitch, Jonathan A.; Berman, Joan W.

    2014-01-01

    Macrophages are the primary cell type infected with HIV in the central nervous system, and infection of these cells is a major component in the development of neuropathogenesis and HIV-associated neurocognitive disorders. Within the brains of drug abusers, macrophages are exposed to increased levels of dopamine, a neurotransmitter that mediates the addictive and reinforcing effects of drugs of abuse such as cocaine and methamphetamine. In this study we examined the effects of dopamine on HIV entry into primary human macrophages. Exposure to dopamine during infection increased the entry of R5 tropic HIV into macrophages, irrespective of the concentration of the viral inoculum. The entry pathway affected was CCR5 dependent, as antagonizing CCR5 with the small molecule inhibitor TAK779 completely blocked entry. The effect was dose-dependent and had a steep threshold, only occurring above 108 M dopamine. The dopamine-mediated increase in entry required dopamine receptor activation, as it was abrogated by the pan-dopamine receptor antagonist flupenthixol, and could be mediated through both subtypes of dopamine receptors. These findings indicate that the effects of dopamine on macrophages may have a significant impact on HIV pathogenesis. They also suggest that drug-induced increases in CNS dopamine may be a common mechanism by which drugs of abuse with distinct modes of action exacerbate neuroinflammation and contribute to HIV-associated neurocognitive disorders in infected drug abusers. PMID:25268786

  4. Prescribed Active Learning Increases Performance in Introductory Biology

    PubMed Central

    O'Connor, Eileen; Parks, John W.; Cunningham, Matthew; Hurley, David; Haak, David; Dirks, Clarissa; Wenderoth, Mary Pat

    2007-01-01

    We tested five course designs that varied in the structure of daily and weekly active-learning exercises in an attempt to lower the traditionally high failure rate in a gateway course for biology majors. Students were given daily multiple-choice questions and answered with electronic response devices (clickers) or cards. Card responses were ungraded; clicker responses were graded for right/wrong answers or participation. Weekly practice exams were done as an individual or as part of a study group. Compared with previous versions of the same course taught by the same instructor, students in the new course designs performed better: There were significantly lower failure rates, higher total exam points, and higher scores on an identical midterm. Attendance was higher in the clicker versus cards section; attendance and course grade were positively correlated. Students did better on clicker questions if they were graded for right/wrong answers versus participation, although this improvement did not translate into increased scores on exams. In this course, achievement increases when students get regular practice via prescribed (graded) active-learning exercises. PMID:17548875

  5. Obesity-induced increases in sympathetic nerve activity: sex matters

    PubMed Central

    Brooks, Virginia L.; Shi, Zhigang; Holwerda, Seth W.; Fadel, Paul J.

    2016-01-01

    Abundant evidence obtained largely from male human and animal subjects indicates that obesity increases sympathetic nerve activity (SNA), which contributes to hypertension development. However, recent studies that included women reported that the strong relationships between muscle SNA and waist circumference or body mass index (BMI) found in men are not present in overweight and obese women. A similar sex difference in the association between adiposity and hypertension development has been identified in animal models of obesity. In this brief review, we consider two possible mechanisms for this sex difference. First, visceral adiposity, leptin, insulin, and angiotensin II have been identified as potential culprits in obesity-induced sympathoexcitation in males. We explore if these factors wield the same impact in females. Second, we consider if sex differences in vascular reactivity to sympathetic activation contribute. Our survey of the literature suggests that premenopausal females may be able to resist obesity-induced sympathoexcitation and hypertension in part due to differences in adipose disposition as well as its muted inflammatory response and reduced production of pressor versus depressor components of the renin-angiotensin system. In addition, vascular responsiveness to increased SNA may be reduced. However, more importantly, we identify the urgent need for further study, not only of sex differences per se, but also of the mechanisms that may mediate these differences. This information is required not only to refine treatment options for obese premenopausal women but also to potentially reveal new therapeutic avenues in obese men and women. PMID:25435000

  6. Baicalein induces G1 arrest in oral cancer cells by enhancing the degradation of cyclin D1 and activating AhR to decrease Rb phosphorylation

    SciTech Connect

    Cheng, Ya-Hsin; Li, Lih-Ann; Lin, Pinpin; Cheng, Li-Chuan; Hung, Chein-Hui; Chang, Nai Wen; Lin, Chingju

    2012-09-15

    Baicalein is a flavonoid, known to have anti-inflammatory and anti-cancer effects. As an aryl hydrocarbon receptor (AhR) ligand, baicalein at high concentrations blocks AhR-mediated dioxin toxicity. Because AhR had been reported to play a role in regulating the cell cycle, we suspected that the anti-cancer effect of baicalein is associated with AhR. This study investigated the molecular mechanism involved in the anti-cancer effect of baicalein in oral cancer cells HSC-3, including whether such effect would be AhR-mediated. Results revealed that baicalein inhibited cell proliferation and increased AhR activity in a dose-dependent manner. Cell cycle was arrested at the G1 phase and the expression of CDK4, cyclin D1, and phosphorylated retinoblastoma (pRb) was decreased. When the AhR was suppressed by siRNA, the reduction of pRb was partially reversed, accompanied by a decrease of cell population at G1 phase and an increase at S phase, while the reduction of cyclin D1 and CDK4 did not change. This finding suggests that the baicalein activation of AhR is indeed associated with the reduction of pRb, but is independent of the reduction of cyclin D1 and CDK4. When cells were pre-treated with LiCl, the inhibitor of GSK-3β, the decrease of cyclin D1 was blocked and the reduction of pRb was recovered. The data indicates that in HSC-3 the reduction of pRb is both mediated by baicalein through activation of AhR and facilitation of cyclin D1 degradation, which causes cell cycle arrest at the G1 phase, and results in the inhibition of cell proliferation. -- Highlights: ► Baicalein causes the G1 phase arrest by decreasing Rb phosphorylation. ► Baicalein modulates AhR-mediated cell proliferation. ► Both AhR activation and cyclin D1 degradation results in hypophosphorylation of Rb. ► Baicalein facilitates cyclin D1 degradation by signalling the GSK-3β pathway.

  7. Effect of increasing the choice of active options on children’s physical activity

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Objectives: To determine whether increasing the choice of physical activity options increases the duration and intensity of children’s physical activity. Design: This cross-sectional laboratory study included gender (male, female) and choice group [single toy (no choice), three toys (low choice...

  8. Geometric complexity is increased in in vitro activated platelets.

    PubMed

    Bianciardi, Giorgio

    2015-06-01

    This article investigates the use of computerized fractal analysis for objective characterization of the complexity of platelets in vitro stimulated by low level thrombin (0.02 U mL(-1) ), collected from healthy individuals and observed by means of transmission electron microscopy. Platelet boundaries were extracted by means of automatically image analysis. Local fractal dimension was evaluated by the box-counting technique (measure of geometric complexity of the platelet outline). The results showed that the platelet boundary is fractal when observed by transmission electron microscopy and that, after an in vitro platelet activation test, the shape of platelets present increased geometric complexity in comparison to the no stimulated platelets (P < 0.001), with 100% correct classification. Computerized fractal analysis of platelet shape by transmission electron microscopy can provide accurate, quantitative, data to study platelet activation. The results may play important roles in the evaluation of the platelets status in pathological conditions, like as atherosclerosis and diabetes mellitus, where in in vivo activated platelets have been described. PMID:25808036

  9. The inhibition of activated hepatic stellate cells proliferation by arctigenin through G0/G1 phase cell cycle arrest: persistent p27(Kip1) induction by interfering with PI3K/Akt/FOXO3a signaling pathway.

    PubMed

    Li, Ao; Wang, Jun; Wu, Mingjun; Zhang, Xiaoxun; Zhang, Hongzhi

    2015-01-15

    Proliferation of hepatic stellate cells (HSCs) is vital for the development of fibrosis during liver injury. In this study, we describe that arctigenin (ATG), a major bioactive component of Fructus Arctii, exhibited selective cytotoxic activity via inhibiting platelet-derived growth factor-BB (PDGF-BB)-activated HSCs proliferation and arrested cell cycle at G0/G1 phase, which could not be observed in normal human hepatocytes in vitro. The cyclin-dependent kinase (CDK) 4/6 activities could be strongly inhibited by ATG through down-regulation of cyclin D1 and CDK4/6 expression in early G1 phase arrest. In the ATG-treated HSCs, the expression level of p27(Kip1) and the formation of CDK2-p27(Kip1) complex were also increased. p27(Kip1) silencing significantly attenuated the effect of ATG, including cell cycle arrest and suppression of proliferation in activated HSCs. We also found that ATG suppressed PDGF-BB-induced phosphorylation of Akt and its downstream transcription factor Forkhead box O 3a (FOXO3a), decreased binding of FOXO3a to 14-3-3 protein, and stimulated nuclear translocation of FOXO3a in activated HSCs. Furthermore, knockdown of FOXO3a expression by FOXO3a siRNA attenuated ATG-induced up-regulation of p27(Kip1) in activated HSCs. All the above findings suggested that ATG could increase the levels of p27(Kip1) protein through inhibition of Akt and improvement of FOXO3a activity, in turn inhibited the CDK2 kinase activity, and eventually caused an overall inhibition of HSCs proliferation. PMID:25498792

  10. NIMS Observes Increased Activity at Loki Patera, Io

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Loki Patera, historically the most active and persistent hot spot on Io, is located on the hemisphere of Io always facing Jupiter. Loki Patera was the site of two plumes during the Voyager encounters, which were not seen during the early orbits of Galileo. Ground-based observers reported Loki Patera to be unusually dim during this time, marking a period of low volcanic activity.

    On 21 February 1997, during Galileo's sixth orbit, the Near Infrared Mapping Spectrometer (NIMS) on the Galileo spacecraft observed Io in daylight from a range of approximately 703,000 km (440,000 miles). The image on the left shows Io at a wavelength of 2.95 microns. Loki Patera is seen to be relatively quiescent (at longer wavelengths which are more sensitive to thermal emission, Loki Patera is more noticeable).

    A few weeks later, on March 12th 1997, ground based observers using the Infra-Red Telescope Facility (IRTF) on Mauna Kea, Hawaii, observed an intense brightening in the Loki region, so much that Loki was contributing 75% of Io's in-eclipse flux for this hemisphere. A large eruption was taking place! Other ground-based observations through March, April and May tracked the course of the activity and confirmed its location at Loki Patera.

    On 4 April 1997, NIMS again observed Io during the seventh orbit from a range of 556,000 km (348,000 miles), with Loki Patera positioned in darkness, close to the limb. The image on the right shows the increase in activity at Loki Patera, again at 2.95 microns. A preliminary single temperature fit to NIMS orbit seven Loki Patera hot spot data yields a temperature of 500 K and an area of over 800 square kilometers. That the image is so bright at this wavelength is an indication of the areal extent of the activity. It is also probable that some part of the volcanic material being erupted or exposed is at considerably higher temperatures than that of the 500 K single-temperature fit.

    Io is under observation by ground-based observers under

  11. Involving Community Stakeholders to Increase Park Use and Physical Activity

    PubMed Central

    Marsh, Terry; Mariscal, Mark; Pina-Cortez, Sophia; Cohen, Deborah A.

    2014-01-01

    Objective To describe implementation of a randomized controlled trial of community-based participatory research (CBPR) approaches to increase park use and physical activity across 33 diverse neighborhoods in Los Angeles. Methods Fifty parks were randomly assigned based on park size, facilities and programs, and neighborhood socio-demographic characteristics to: park director (PD, 17 parks); PD and park advisory board of interested community members (PD+PAB, 16 parks); and no-intervention control (17 parks) arms. Between 2007 and 2012, PDs and PABs from the 33 intervention parks participated in community engagement, baseline assessment, marketing training, intervention design and implementation, and follow-up assessment. Results Intervention parks (PD and PD+PAB) invested in new and diversified signage, promotional items, outreach or support for group activities like fitness classes and walking clubs, and various marketing strategies. Scaling up CBPR methods across parks in 33 diverse neighborhoods was challenging. Working with departmental management and established structures for community input (PABs) and park policy (PDs) facilitated implementation and sustainability. Conclusion Scaling up CBPR methods across diverse communities involved tradeoffs. CBPR is useful for tailoring research and enhancing community impact and sustainability, but more work is needed to understand how to conduct multi-site trials across diverse settings using CBPR. PMID:24674853

  12. L-tyrosine administration increases acetylcholinesterase activity in rats.

    PubMed

    Ferreira, Gabriela K; Carvalho-Silva, Milena; Gonçalves, Cinara L; Vieira, Júlia S; Scaini, Giselli; Ghedim, Fernando V; Deroza, Pedro F; Zugno, Alexandra I; Pereira, Talita C B; Oliveira, Giovanna M T; Kist, Luiza W; Bogo, Maurício R; Schuck, Patrícia F; Ferreira, Gustavo C; Streck, Emilio L

    2012-12-01

    Tyrosinemia is a rare genetic disease caused by mutations on genes that codify enzymes responsible for tyrosine metabolism. Considering that tyrosinemics patients usually present symptoms associated with central nervous system alterations that ranges from slight decreases in intelligence to severe mental retardation, we decided to investigate whether acute and chronic administration of L-tyrosine in rats would affect acetylcholinesterase mRNA expression and enzymatic activity during their development. In our acute protocol, Wistar rats (10 and 30 days old) were killed one hour after a single intraperitoneal L-tyrosine injection (500 mg/kg) or saline. Chronic administration consisted of L-tyrosine (500 mg/kg) or saline injections 12 h apart for 24 days in Wistar rats (7 days old) and rats were killed 12 h after last injection. Acetylcholinesterase activity was measured by Ellman's method and acetylcholinesterase expression was carried out by a semi-quantitative reverse transcriptase polymerase chain reaction (RT-PCR) assay. We observed that acute (10 and 30 days old rats) and chronic L-tyrosine administration increased acetylcholinesterase activity in serum and all tested brain areas (hippocampus, striatum and cerebral cortex) when compared to control group. Moreover, there was a significant decrease in mRNA levels of acetylcholinesterase in hippocampus was observed after acute protocol (10 and 30 days old rats) and in striatum after chronic protocol. In case these alterations also occur in the brain of the patients, our results may explain, at least in part, the neurological sequelae associated with high plasma concentrations of tyrosine seen in patients affected by tyrosinemia type II. PMID:23046746

  13. Increased oscillatory theta activation evoked by violent digital game events.

    PubMed

    Salminen, Mikko; Ravaja, Niklas

    2008-04-11

    The authors examined electroencephalographic (EEG) oscillatory responses to two violent events, the player character wounding and killing an opponent character with a gun, in the digital game James Bond 007: NightFire. EEG was recorded from 25 (16 male) right-handed healthy young adults. EEG data were segmented into one 1-s baseline epoch before each event and two 1-s epochs after event onset. Power estimates (microV(2)) were derived with the fast Fourier transform (FFT) for each artefact free event. Both of the studied events evoked increased occipital theta (4-6Hz) responses as compared to the pre-event baseline. The wounding event evoked also increased occipital high theta (6-8Hz) response and the killing event evoked low alpha (8-10Hz) asymmetry over the central electrodes, both relative to the pre-event baseline. The results are discussed in light of facial electromyographic and electrodermal activity responses evoked by these same events, and it is suggested that the reported EEG responses may be attributable to affective processes related to these violent game events. PMID:18325669

  14. Acid-activated biochar increased sulfamethazine retention in soils.

    PubMed

    Vithanage, Meththika; Rajapaksha, Anushka Upamali; Zhang, Ming; Thiele-Bruhn, Sören; Lee, Sang Soo; Ok, Yong Sik

    2015-02-01

    Sulfamethazine (SMZ) is an ionizable and highly mobile antibiotic which is frequently found in soil and water environments. We investigated the sorption of SMZ onto soils amended with biochars (BCs) at varying pH and contact time. Invasive plants were pyrolyzed at 700 °C and were further activated with 30 % sulfuric (SBBC) and oxalic (OBBC) acids. The sorption rate of SMZ onto SBBC and OBBC was pronouncedly pH dependent and was decreased significantly when the values of soil pH increased from 3 to 5. Modeled effective sorption coefficients (K D,eff) values indicated excellent sorption on SBBC-treated loamy sand and sandy loam soils for 229 and 183 L/kg, respectively. On the other hand, the low sorption values were determined for OBBC- and BBC700-treated loamy sand and sandy loam soils. Kinetic modeling demonstrated that the pseudo second order model was the best followed by intra-particle diffusion and the Elovich model, indicating that multiple processes govern SMZ sorption. These findings were also supported by sorption edge experiments based on BC characteristics. Chemisorption onto protonated and ligand containing functional groups of the BC surface, and diffusion in macro-, meso-, and micro-pores of the acid-activated BCs are the proposed mechanisms of SMZ retention in soils. Calculated and experimental q e (amount adsorbed per kg of the adsorbent at equilibrium) values were well fitted to the pseudo second order model, and the predicted maximum equilibrium concentration of SBBC for loamy sand soils was 182 mg/kg. Overall, SBBC represents a suitable soil amendment because of its high sorption rate of SMZ in soils. PMID:25172460

  15. Immobilization induces a very rapid increase in osteoclast activity

    NASA Astrophysics Data System (ADS)

    Heer, Martina; Baecker, Natalie; Mika, Claudia; Boese, Andrea; Gerzer, Rupert

    2005-07-01

    We studied in a randomized, strictly controlled cross-over design, the effects of 6 days 6° head-down tilt bed rest (HDT) in eight male healthy subjects in our metabolic ward. The study consisted of two periods (phases) of 11 days each in order to allow for the test subjects being their own controls. Both study phases were identical with respect to environmental conditions, study protocol and diet. Two days before arriving in the metabolic ward the subjects started with a diet. The diet was continued in the metabolic ward. The metabolic ward period (1l days) was divided into three parts: 4 ambulatory days, 6 days either HDT or control and 1 recovery day. Continuous urine collection started on the first day in the metabolic ward to analyze calcium excretion and bone resorption markers. On the 2nd ambulatory day in the metabolic ward and on the 5th day in HDT or control blood was drawn to analyze serum calcium, parathyroid hormone, and bone formation markers. Urinary calcium excretion was, as early as the first day in immobilization, increased (p<0.01). CTX- and NTX-excretion stayed unchanged in the first 24 h in HDT compared to the control. But already on the 2nd day of immobilization, both bone resorption markers significantly increased. We conclude from these results—pronounced rise of bone resorption markers—that already 24 h of immobilization induce a significant rise in osteoclast activity in healthy subjects. Thus, it appears possible to use short-term bed rest studies as a first step for the development of countermeasures to immobilization.

  16. Increased 5. cap alpha. -reductase activity in idiopathic hirsutism

    SciTech Connect

    Serafini, P.; Lobo, R.A.

    1985-01-01

    In vitro, genital skin 5..cap alpha..-reductase activity (5..cap alpha..-RA) was measured in ten hirsute women with normal androgen levels (idiopathic hirsutism (IH)) and in ten hirsute women with elevated androgen levels (polycystic ovary syndrome (PCO)) in order to determine the influence of secreted androgens on 5..cap alpha..-RA. In vitro 5..cap alpha..-RA was assessed by incubations of skin with /sup 14/C-testosterone (T) for 2 hours, after which steroids were separated and the radioactivity of dihydrotestosterone (DHT) and 5..cap alpha..-androstane 3..cap alpha..-17..beta..-estradiol (3..cap alpha..-diol) in specific eluates were determined. All androgens were normal in IH with the exception of higher levels of 3..cap alpha..-diol glucuronide which were similar to the levels of PCO. The conversion ratio (CR) of T to DHT in IH and PCO were similar, yet significantly greater than the CR of control subjects. The CR of T to 3..cap alpha..-diol in IH and PCO were similar, yet higher than in control subjects. Serum androgens showed no correlation with 5..cap alpha..-RA, while the CR of T to DHT showed a significant positive correlation with the Ferriman and Gallwey score. The increased 5..cap alpha..-RA in IH appears to be independent of serum androgen levels and is, therefore, an inherent abnormality. The term idiopathic is a misnomer, because hirsutism in these patients may be explained on the basis of increased skin 5..cap alpha..-RA.

  17. Chronic electrical stimulation homeostatically decreases spontaneous activity, but paradoxically increases evoked network activity

    PubMed Central

    Goel, Anubhuti

    2013-01-01

    Neural dynamics generated within cortical networks play a fundamental role in brain function. However, the learning rules that allow recurrent networks to generate functional dynamic regimes, and the degree to which these regimes are themselves plastic, are not known. In this study we examined plasticity of network dynamics in cortical organotypic slices in response to chronic changes in activity. Studies have typically manipulated network activity pharmacologically; we used chronic electrical stimulation to increase activity in in vitro cortical circuits in a more physiological manner. Slices were stimulated with “implanted” electrodes for 4 days. Chronic electrical stimulation or treatment with bicuculline decreased spontaneous activity as predicted by homeostatic learning rules. Paradoxically, however, whereas bicuculline decreased evoked network activity, chronic stimulation actually increased the likelihood that evoked stimulation elicited polysynaptic activity, despite a decrease in evoked monosynaptic strength. Furthermore, there was an inverse correlation between spontaneous and evoked activity, suggesting a homeostatic tradeoff between spontaneous and evoked activity. Within-slice experiments revealed that cells close to the stimulated electrode exhibited more evoked polysynaptic activity and less spontaneous activity than cells close to a control electrode. Collectively, our results establish that chronic stimulation changes the dynamic regimes of networks. In vitro studies of homeostatic plasticity typically lack any external input, and thus neurons must rely on “spontaneous” activity to reach homeostatic “set points.” However, in the presence of external input we propose that homeostatic learning rules seem to shift networks from spontaneous to evoked regimes. PMID:23324317

  18. Altered behaviour in spotted hyenas associated with increased human activity

    USGS Publications Warehouse

    Boydston, E.E.; Kapheim, K.M.; Watts, H.E.; Szykman, M.; Holekamp, K.E.

    2003-01-01

    To investigate how anthropogenic activity might affect large carnivores, we studied the behaviour of spotted hyenas (Crocuta crocuta) during two time periods. From 1996 to 1998, we documented the ecological correlates of space utilization patterns exhibited by adult female hyenas defending a territory at the edge of a wildlife reserve in Kenya. Hyenas preferred areas near dense vegetation but appeared to avoid areas containing the greatest abundance of prey, perhaps because these were also the areas of most intensive livestock grazing. We then compared hyena behaviour observed in 1996-98 with that observed several years earlier and found many differences. Female hyenas in 1996-98 were found farther from dens, but closer to dense vegetation and to the edges of their territory, than in 1988-90. Recent females also had larger home ranges, travelled farther between consecutive sightings, and were more nocturnal than in 1988-90. Finally, hyenas occurred in smaller groups in 1996-98 than in 1988-90. We also found several changes in hyena demography between periods. We next attempted to explain differences observed between time periods by testing predictions of hypotheses invoking prey abundance, climate, interactions with lions, tourism and livestock grazing. Our data were consistent with the hypothesis that increased reliance on the reserve for livestock grazing was responsible for observed changes. That behavioural changes were not associated with decreased hyena population density suggests the behavioural plasticity typical of this species may protect it from extinction. ?? 2003 The Zoological Society of London.

  19. Nest predation increases with parental activity: Separating nest site and parental activity effects

    USGS Publications Warehouse

    Martin, T.E.; Scott, J.; Menge, C.

    2000-01-01

    Alexander Skutch hypothesized that increased parental activity can increase the risk of nest predation. We tested this hypothesis using ten open-nesting bird species in Arizona, USA. Parental activity was greater during the nestling than incubation stage because parents visited the nest frequently to feed their young during the nestling stage. However, nest predation did not generally increase with parental activity between nesting stages across the ten study species. Previous investigators have found similar results. We tested whether nest site effects might yield higher predation during incubation because the most obvious sites are depredated most rapidly. We conducted experiments using nest sites from the previous year to remove parental activity. Our results showed that nest sites have highly repeatable effects on nest predation risk; poor nest sites incurred rapid predation and caused predation rates to be greater during the incubation than nestling stage. This pattern also was exhibited in a bird species with similar (i.e. controlled) parental activity between nesting stages. Once nest site effects are taken into account, nest predation shows a strong proximate increase with parental activity during the nestling stage within and across species. Parental activity and nest sites exert antagonistic influences on current estimates of nest predation between nesting stages and both must be considered in order to understand current patterns of nest predation, which is an important source of natural selection.

  20. Nest predation increases with parental activity: separating nest site and parental activity effects.

    PubMed Central

    Martin, T E; Scott, J; Menge, C

    2000-01-01

    Alexander Skutch hypothesized that increased parental activity can increase the risk of nest predation. We tested this hypothesis using ten open-nesting bird species in Arizona, USA. Parental activity was greater during the nestling than incubation stage because parents visited the nest frequently to feed their young during the nestling stage. However, nest predation did not generally increase with parental activity between nesting stages across the ten study species. Previous investigators have found similar results. We tested whether nest site effects might yield higher predation during incubation because the most obvious sites are depredated most rapidly. We conducted experiments using nest sites from the previous year to remove parental activity. Our results showed that nest sites have highly repeatable effects on nest predation risk; poor nest sites incurred rapid predation and caused predation rates to be greater during the incubation than nestling stage. This pattern also was exhibited in a bird species with similar (i.e. controlled) parental activity between nesting stages. Once nest site effects are taken into account, nest predation shows a strong proximate increase with parental activity during the nestling stage within and across species. Parental activity and nest sites exert antagonistic influences on current estimates of nest predation between nesting stages and both must be considered in order to understand current patterns of nest predation, which is an important source of natural selection. PMID:11413645

  1. Engaging parents to increase youth physical activity: A systematic review

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Parents are often involved in interventions to engage youth in physical activity, but it is not clear which methods for involving parents are effective. A systematic review was conducted of interventions with physical activity and parental components among healthy youth to identify how best to invol...

  2. Opportunities for public health to increase physical activity among youths.

    PubMed

    Piercy, Katrina L; Dorn, Joan M; Fulton, Janet E; Janz, Kathleen F; Lee, Sarah M; McKinnon, Robin A; Pate, Russell R; Pfeiffer, Karin A; Young, Deborah Rohm; Troiano, Richard P; Lavizzo-Mourey, Risa

    2015-03-01

    Despite the well-known benefits of youths engaging in 60 or more minutes of daily physical activity, physical inactivity remains a significant public health concern. The 2008 Physical Activity Guidelines for Americans (PAG) provides recommendations on the amount of physical activity needed for overall health; the PAG Midcourse Report (2013) describes effective strategies to help youths meet these recommendations. Public health professionals can be dynamic change agents where youths live, learn, and play by changing environments and policies to empower youths to develop regular physical activity habits to maintain throughout life. We have summarized key findings from the PAG Midcourse Report and outlined actions that public health professionals can take to ensure that all youths regularly engage in health-enhancing physical activity. PMID:25602864

  3. Postural Cueing to Increase Lumbar Lordosis Increases Lumbar Multifidus Activation During Trunk Stabilization Exercises: Electromyographic Assessment Using Intramuscular Electrodes.

    PubMed

    Beneck, George J; Story, John W; Donald, Shelby

    2016-04-01

    Study Design Controlled laboratory study, repeated-measures design. Background Diminished multifidus activation and cross-sectional area are frequent findings in persons with low back pain. Increasing lumbar lordosis has been shown to increase activation of the multifidus with a minimal increase in activation of the long global extensors during unsupported sitting. Objectives To examine the influence of postural cueing to increase lumbar lordosis on lumbar extensor activation during trunk stabilization exercises. Methods Thirteen asymptomatic participants (9 male, 4 female) were instructed to perform 6 trunk stabilization exercises using a neutral position and increasing lumbar lordosis. Electrical activity of the deep multifidus and longissimus thoracis was recorded using fine-wire intramuscular electrodes. The mean root-mean-square of the electromyography (EMG) signal obtained during each exercise was normalized to a maximum voluntary isometric contraction (MVIC). A 2-way, repeated-measures analysis of variance (posture by exercise) was performed for each muscle. Results When averaged across the 6 exercises, postural cueing to increase lumbar lordosis resulted in greater multifidus EMG activity compared to performing the exercises in a neutral posture (35.3% ± 15.1% versus 29.5% ± 11.2% MVIC). No significant increase in longissimus thoracis EMG activity was observed when exercising with cueing to increase lumbar lordosis. Conclusion This study suggests that postural cueing to increase lumbar lordosis during trunk stabilization exercises may better promote multifidus activation than traditional stabilization exercises alone. Future studies are needed to determine whether increasing lumbar lordosis improves multifidus activation in persons with low back pain. J Orthop Sports Phys Ther 2016;46(4):293-299. Epub 8 Mar 2016. doi:10.2519/jospt.2016.6174. PMID:26954268

  4. Synergistic activity of BET protein antagonist-based combinations in mantle cell lymphoma cells sensitive or resistant to ibrutinib.

    PubMed

    Sun, Baohua; Shah, Bhavin; Fiskus, Warren; Qi, Jun; Rajapakshe, Kimal; Coarfa, Cristian; Li, Li; Devaraj, Santhana G T; Sharma, Sunil; Zhang, Liang; Wang, Michael L; Saenz, Dyana T; Krieger, Stephanie; Bradner, James E; Bhalla, Kapil N

    2015-09-24

    Mantle cell lymphoma (MCL) cells exhibit increased B-cell receptor and nuclear factor (NF)-κB activities. The bromodomain and extra-terminal (BET) protein bromodomain 4 is essential for the transcriptional activity of NF-κB. Here, we demonstrate that treatment with the BET protein bromodomain antagonist (BA) JQ1 attenuates MYC and cyclin-dependent kinase (CDK)4/6, inhibits the nuclear RelA levels and the expression of NF-κB target genes, including Bruton tyrosine kinase (BTK) in MCL cells. Although lowering the levels of the antiapoptotic B-cell lymphoma (BCL)2 family proteins, BA treatment induces the proapoptotic protein BIM and exerts dose-dependent lethality against cultured and primary MCL cells. Cotreatment with BA and the BTK inhibitor ibrutinib synergistically induces apoptosis of MCL cells. Compared with each agent alone, cotreatment with BA and ibrutinib markedly improved the median survival of mice engrafted with the MCL cells. BA treatment also induced apoptosis of the in vitro isolated, ibrutinib-resistant MCL cells, which overexpress CDK6, BCL2, Bcl-xL, XIAP, and AKT, but lack ibrutinib resistance-conferring BTK mutation. Cotreatment with BA and panobinostat (pan-histone deacetylase inhibitor) or palbociclib (CDK4/6 inhibitor) or ABT-199 (BCL2 antagonist) synergistically induced apoptosis of the ibrutinib-resistant MCL cells. These findings highlight and support further in vivo evaluation of the efficacy of the BA-based combinations with these agents against MCL, including ibrutinib-resistant MCL. PMID:26254443

  5. Synergistic activity of BET protein antagonist-based combinations in mantle cell lymphoma cells sensitive or resistant to ibrutinib

    PubMed Central

    Sun, Baohua; Shah, Bhavin; Fiskus, Warren; Qi, Jun; Rajapakshe, Kimal; Coarfa, Cristian; Li, Li; Devaraj, Santhana G. T.; Sharma, Sunil; Zhang, Liang; Wang, Michael L.; Saenz, Dyana T.; Krieger, Stephanie; Bradner, James E.

    2015-01-01

    Mantle cell lymphoma (MCL) cells exhibit increased B-cell receptor and nuclear factor (NF)-κB activities. The bromodomain and extra-terminal (BET) protein bromodomain 4 is essential for the transcriptional activity of NF-κB. Here, we demonstrate that treatment with the BET protein bromodomain antagonist (BA) JQ1 attenuates MYC and cyclin-dependent kinase (CDK)4/6, inhibits the nuclear RelA levels and the expression of NF-κB target genes, including Bruton tyrosine kinase (BTK) in MCL cells. Although lowering the levels of the antiapoptotic B-cell lymphoma (BCL)2 family proteins, BA treatment induces the proapoptotic protein BIM and exerts dose-dependent lethality against cultured and primary MCL cells. Cotreatment with BA and the BTK inhibitor ibrutinib synergistically induces apoptosis of MCL cells. Compared with each agent alone, cotreatment with BA and ibrutinib markedly improved the median survival of mice engrafted with the MCL cells. BA treatment also induced apoptosis of the in vitro isolated, ibrutinib-resistant MCL cells, which overexpress CDK6, BCL2, Bcl-xL, XIAP, and AKT, but lack ibrutinib resistance-conferring BTK mutation. Cotreatment with BA and panobinostat (pan-histone deacetylase inhibitor) or palbociclib (CDK4/6 inhibitor) or ABT-199 (BCL2 antagonist) synergistically induced apoptosis of the ibrutinib-resistant MCL cells. These findings highlight and support further in vivo evaluation of the efficacy of the BA-based combinations with these agents against MCL, including ibrutinib-resistant MCL. PMID:26254443

  6. Increasing Physical Activity in Children: From Evidence to Action.

    PubMed

    Jakubowski, Tami L; Faigenbaum, Avery D; Lindberg, Claire

    2015-01-01

    Daily physical activity has the potential to improve health and well-being, yet worldwide surveillance of physical activity levels indicate a growing number of children and adolescents do not meet current physical activity recommendations. The current symptom-reactive paradigm should be reconsidered, and preventive actions initiated, before inactive children become resistant to targeted interventions and require pharmacotherapy, and expensive medical procedures for treatment of preventable illnesses. A cascade of adverse events are associated with a sedentary lifestyle. Nurses are uniquely qualified to identify youth with exercise deficits and encourage daily participation in a variety of age-related physical activities that enhance both health- and skill-related components of physical fitness.Physical activity guidelines should support evidence-based activity recommendations by nurses working with children. New insights regarding the importance of improving muscular strength and motor skill performance early in life are valuable to nurses in formulating exercise recommendations for school-age youth. Specific education in pediatric exercise science provides the foundation for prescribing age-related exercise interventions consistent with the needs, abilities, and interests of infants, toddlers, children, and adolescents. Given the critical importance of primary prevention, transformational change in the current system for identifying and treating youth with exercise deficits is warranted. PMID:25811394

  7. Avian Reovirus Protein p17 Functions as a Nucleoporin Tpr Suppressor Leading to Activation of p53, p21 and PTEN and Inactivation of PI3K/AKT/mTOR and ERK Signaling Pathways.

    PubMed

    Huang, Wei-Ru; Chiu, Hung-Chuan; Liao, Tsai-Ling; Chuang, Kuo-Pin; Shih, Wing-Ling; Liu, Hung-Jen

    2015-01-01

    Avian reovirus (ARV) protein p17 has been shown to regulate cell cycle and autophagy by activation of p53/PTEN pathway; nevertheless, it is still unclear how p53 and PTEN are activated by p17. Here, we report for the first time that p17 functions as a nucleoporin Tpr suppressor that leads to p53 nuclear accumulation and consequently activates p53, p21, and PTEN. The nuclear localization signal (119IAAKRGRQLD128) of p17 has been identified for Tpr binding. This study has shown that Tpr suppression occurs by p17 interacting with Tpr and by reducing the transcription level of Tpr, which together inhibit Tpr function. In addition to upregulation of PTEN by activation of p53 pathway, this study also suggests that ARV protein p17 acts as a positive regulator of PTEN. ARV p17 stabilizes PTEN by stimulating phosphorylation of cytoplasmic PTEN and by elevating Rak-PTEN association to prevent it from E3 ligase NEDD4-1 targeting. To activate PTEN, p17 is able to promote β-arrestin-mediated PTEN translocation from the cytoplasm to the plasma membrane via a Rock-1-dependent manner. The accumulation of p53 in the nucleus induces the PTEN- and p21-mediated downregulation of cyclin D1 and CDK4. Furthermore, Tpr and CDK4 knockdown increased virus production in contrast to depletion of p53, PTEN, and LC3 reducing virus yield. Taken together, our data suggest that p17-mediated Tpr suppression positively regulates p53, PTEN, and p21 and negatively regulates PI3K/AKT/mTOR and ERK signaling pathways, both of which are beneficial for virus replication. PMID:26244501

  8. Avian Reovirus Protein p17 Functions as a Nucleoporin Tpr Suppressor Leading to Activation of p53, p21 and PTEN and Inactivation of PI3K/AKT/mTOR and ERK Signaling Pathways

    PubMed Central

    Huang, Wei-Ru; Chiu, Hung-Chuan; Liao, Tsai-Ling; Chuang, Kuo-Pin; Shih, Wing-Ling; Liu, Hung-Jen

    2015-01-01

    Avian reovirus (ARV) protein p17 has been shown to regulate cell cycle and autophagy by activation of p53/PTEN pathway; nevertheless, it is still unclear how p53 and PTEN are activated by p17. Here, we report for the first time that p17 functions as a nucleoporin Tpr suppressor that leads to p53 nuclear accumulation and consequently activates p53, p21, and PTEN. The nuclear localization signal (119IAAKRGRQLD128) of p17 has been identified for Tpr binding. This study has shown that Tpr suppression occurs by p17 interacting with Tpr and by reducing the transcription level of Tpr, which together inhibit Tpr function. In addition to upregulation of PTEN by activation of p53 pathway, this study also suggests that ARV protein p17 acts as a positive regulator of PTEN. ARV p17 stabilizes PTEN by stimulating phosphorylation of cytoplasmic PTEN and by elevating Rak-PTEN association to prevent it from E3 ligase NEDD4-1 targeting. To activate PTEN, p17 is able to promote β-arrestin-mediated PTEN translocation from the cytoplasm to the plasma membrane via a Rock-1-dependent manner. The accumulation of p53 in the nucleus induces the PTEN- and p21-mediated downregulation of cyclin D1 and CDK4. Furthermore, Tpr and CDK4 knockdown increased virus production in contrast to depletion of p53, PTEN, and LC3 reducing virus yield. Taken together, our data suggest that p17-mediated Tpr suppression positively regulates p53, PTEN, and p21 and negatively regulates PI3K/AKT/mTOR and ERK signaling pathways, both of which are beneficial for virus replication. PMID:26244501

  9. China's Changbaishan volcano showing signs of increased activity

    NASA Astrophysics Data System (ADS)

    Schultz, Colin

    2012-10-01

    Roughly 1100 years ago, the Changbaishan volcano that lies along the border between northeastern China and North Korea erupted, sending pyroclastic flows dozens of kilometers and blasting a 5-kilometer-wide chunk off of the tip of the stratovolcano. The eruption, known as the Millennium eruption because of its proximity to the turn of the first millennium, was one of the largest volcanic events in the Common Era. In the subsequent period, there have been three smaller eruptions, the most recent of which took place in 1903. Starting in 1999, spurred by signs of resumed activity, scientists established the Changbaishan Volcano Observatory, a network to track changing gas compositions, seismic activity, and ground deformation. Reporting on the data collected over the past 12 years, Xu et al. found that these volcanic indices each leapt during a period of heightened activity from 2002 to 2006.

  10. Dipeptides Increase Functional Activity of Human Skin Fibroblasts.

    PubMed

    Malinin, V V; Durnova, A O; Polyakova, V O; Kvetnoi, I M

    2015-05-01

    We analyzed the effect of dipeptide Glu-Trp and isovaleroyl-Glu-Trp in concentrations of 0.2, 2 and 20 μg/ml and Actovegin preparation on functional activity of human skin fibroblasts. Dipeptides, especially Glu-Trp, produce a stimulating effect on human skin fibroblasts and their effect is equivalent to that of Actovegin. Dipeptides stimulate cell renewal processes by activating synthesis of Ki-67 and reducing expression of caspase-9 and enhance antioxidant function of the cells by stimulating the expression of Hsp-90 and inducible NO-synthase. These findings suggest that dipeptides are promising candidates for preparations stimulating reparative processes. PMID:26033609

  11. Somatosensory Anticipatory Alpha Activity Increases to Suppress Distracting Input

    ERIC Educational Resources Information Center

    Haegens, Saskia; Luther, Lisa; Jensen, Ole

    2012-01-01

    Effective processing of sensory input in daily life requires attentional selection and amplification of relevant input and, just as importantly, attenuation of irrelevant information. It has been proposed that top-down modulation of oscillatory alpha band activity (8-14 Hz) serves to allocate resources to various regions, depending on task…

  12. Texting to increase physical activity in teens: Development & preliminary

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Our purpose was to present formative research and preliminary results for a self-determination-theory (SDT)-based text messages to promote physical activity (PA) among teens. Thirty 14- to 17-year olds, stratified by gender and race/ethnicity (Black, Hispanic, White), were recruited to participate i...

  13. Increasing Pupil Physical Activity: A Comprehensive Professional Development Effort

    ERIC Educational Resources Information Center

    Kulinna, Pamela Hodges

    2012-01-01

    Study aim: To determine if pupil physical activity and Body Mass Index classifications maintained or improved after a one-year professional development program involving both classroom and physical education teachers. Guskey's model of teacher change guided this study. Material and methods: Indigenous children from ten schools (N = 320) in grades…

  14. VERB [TM] Summer Scorecard: Increasing Tween Girls' Vigorous Physical Activity

    ERIC Educational Resources Information Center

    Alfonso, Moya L.; Thompson, Zachary; McDermott, Robert J.; Colquitt, Gavin; Jones, Jeffery A.; Bryant, Carol A.; Courtney, Anita H.; Davis, Jenna L.; Zhu, Yiliang

    2013-01-01

    Objective: We assessed changes in the frequency of self-reported physical activity (PA) among tween girls exposed and not exposed to the VERB [TM] Summer Scorecard (VSS) intervention in Lexington, Kentucky, during 2004, 2006, and 2007. Methods: Girls who reported 0-1 day per week of PA were classi?ed as having "little or no" PA. Girls who reported…

  15. Increasing Physical Activity of Children during School Recess

    ERIC Educational Resources Information Center

    Hayes, Lynda B.; Van Camp, Carole M.

    2015-01-01

    Physical activity is crucial for children's health. Fitbit accelerometers were used to measure steps of 6 elementary students during recess. The intervention included reinforcement, self-monitoring, goal setting, and feedback. Steps taken during the intervention phase (M?=?1,956 steps) were 47% higher than in baseline (M?=?1,326 steps), and the…

  16. Soil disturbance increases soil microbial enzymatic activity in arid ecoregion

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Functional diversity of the soil microbial community is commonly used in the assessment of soil health as it relates to the activity of soil microflora involved in carbon cycling. Soil microbes in different microenvironments will have varying responses to different substrates, thus catabolic fingerp...

  17. T Lymphocyte Activation Threshold is Increased in Reduced Gravity

    NASA Technical Reports Server (NTRS)

    Adams, Charley L.; Gonzalez, M.; Sams, C. F.

    2000-01-01

    There have been substantial advances in molecular and cellular biology that have provided new insight into the biochemical and genetic basis of lymphocyte recognition, activation and expression of distinct functional phenotypes. It has now become evident that for both T and B cells, stimuli delivered through their receptors can result in either clonal expansion or apoptosis. In the case of T cells, clonal expansion of helper cells is accompanied by differentiation into two major functional subsets which regulate the immune response. The pathways between the membrane and the nucleus and their molecular components are an area of very active investigation. This meeting will draw together scientists working on diverse aspects of this problem, including receptor ligand interactions, intracellular pathways that transmit receptor mediated signals and the effect of such signal transduction pathways on gene regulation. The aim of this meeting is to integrate the information from these various experimental approaches into a new synthesis and molecular explanation of T cell activation, differentiation and death.

  18. Increased physical activity has a greater effect than reduced energy intake on lifestyle modification-induced increases in testosterone.

    PubMed

    Kumagai, Hiroshi; Zempo-Miyaki, Asako; Yoshikawa, Toru; Tsujimoto, Takehiko; Tanaka, Kiyoji; Maeda, Seiji

    2016-01-01

    Obesity has reached epidemic proportions worldwide. Obesity results in reduced serum testosterone levels, which causes many disorders in men. Lifestyle modifications (increased physical activity and calorie restriction) can increase serum testosterone levels. However, it is unknown whether increased physical activity or calorie restriction during lifestyle modifications has a greater effects on serum testosterone levels. Forty-one overweight and obese men completed a 12-week lifestyle modification program (aerobic exercise training and calorie restriction). We measured serum testosterone levels, the number of steps, and the total energy intake. We divided participants into two groups based on the median change in the number of steps (high or low physical activities) or that in calorie restriction (high or low calorie restrictions). After the program, serum testosterone levels were significantly increased. Serum testosterone levels in the high physical activity group were significantly higher than those in the low activity group. This effect was not observed between the groups based on calorie restriction levels. We found a significant positive correlation between the changes in serum testosterone levels and the number of steps. Our results suggested that an increase in physical activity greatly affected the increased serum testosterone levels in overweight and obese men during lifestyle modification. PMID:26798202

  19. Proteolytic activity of Oenococcus oeni enables the increase in antioxidant and antihypertensive activities from wine.

    PubMed

    Apud, Gisselle Raquel; Stivala, María Gilda; Fernández, Pedro Aredes; Rodríguez Vaquero, María José

    2013-01-01

    Oenococcus oeni is a lactic acid bacterium involved in winemaking where it generally carries out the malolactic fermentation converting the wine's malic acid into lactic acid. In this work were used the strain m of Oenococcus oeni. The culture was inoculated at 10⁸ Log CFU/mL in a synthetic wine medium (SW) supplemented with a fraction of high molecular weight constituted by proteins and polypeptides (FPP) obtained from Cabernet Sauvignon and Syrah wines from Colalao del Valle, Tucumán, Argentine. In presence of FPP, O. oeni maintains viability after 48 h incubation time and release an extracellular proteolytic activity. Therefore, a release peptides of 1.247 and 1.373 mg N/L at 48 h of incubation time was detected in SW supplemented with FPP from Cabernet Sauvignon and Syrah wines respectively. Concomitantly with the maximum peptide release, the "in vitro" biological activities were increased. The released peptides from Cabernet Sauvignon wine enables the increase in the ferric reducing antioxidant power (FRAP) capacity, the scavenging activity of 2,2-diphenyl-1-picrylhydrazyl radical (DPPH), and the inhibition of angiotensin I-converting enzyme (ACEI activity) in 392.8 µmol FeSO₄/L, 9.7% and 63.9%, respectively. In presence of FPP of Syrah wine, the released peptides increases in 156.5 µmol FeSO₄/L, 5.5% and 13.8% the FRAP, DPPH and ACEI activities, respectively. The utilization of Oenococcus oeni m to carry out the malolactic fermentation would contribute to enhance the beneficial biological activities of the final product and provide an additional value to regional wines. PMID:24372266

  20. Temperature increasing trend due to solar activity at Western Saudi

    NASA Astrophysics Data System (ADS)

    Almleaky, Y. M.; Sharaf, M. A.; Basurah, H. M.; Malawi, A. A.; Al-Mostafa, Z. A.

    The Sun influnce on climate has been discussed globaly by many authors and at different latitudes. In this article we will discuss this connection for the Kingdom of Saudi Arabia, which spans a large area, i.e. 16-32 North and 36-50 East. We started our invistigation in this paper by looking into the temperature at the Western coast of the Kingdom, namely Yenbo and Jeddah. In order to find the correlation between temperature and solar variations we employed one of the most relevant solar quentity, i.e. the solar cycle length. From our invistigations we found an increase in the temperature averages reaching up to 1.0 degree Celsius in certain cities since 1970. It is also found that the temperature increase is strongly correlated with the solar Cycle length, reaching up to 0.8 in some sites.

  1. Increasing nurse and midwife engagement in research activity.

    PubMed

    Mitchell, Kay; Baillie, Lesley; Phillips, Natasha

    2015-02-10

    Nurses and midwives should be able to perform, interpret and implement the results of clinical research to improve the quality of patient care. Increasing the research capacity and capability of healthcare professionals requires strong leadership and a strategic approach. This article describes how one NHS trust supports engagement of nurses and midwives in research through the development of a research strategy and a centre for nurse and midwife-led research. PMID:25649601

  2. Density increase due to active feedback in mirror machine

    NASA Astrophysics Data System (ADS)

    Seemann, Omri; Be'Ery, Ilan

    2014-10-01

    Mirror machines are one of the schemes for future fusion systems. Its main drawbacks are the flute instability and being open ended which results in plasma losses. A feedback system is used to stabilize the flute instability in a table top mirror machine with a continuous plasma source and RF heating. Under certain source density and temperature conditions, although the plasma was stabilized, plasma density increase was not measured. After decreasing the source density and increasing the temperature, Plasma density increase was achieved. It is theorized that these results are due to transition of the plasma main loss mechanism from collision dominated to instability dominated. In the former, the main density loss is through diffusion and In the latter, it is through flute instability which drives the plasma to the edge of the vacuum chamber. Future research directions are discussed for a planned machine which should achieve higher temperatures and better diagnostic capabilities. The research will focus on magnetic actuators and passive RF stabilization.

  3. Mobile Phone Interventions to Increase Physical Activity and Reduce Weight

    PubMed Central

    Stephens, Janna; Allen, Jerilyn

    2013-01-01

    Objective This systematic review was conducted to determine user satisfaction and effectiveness of smartphone applications and text messaging interventions to promote weight reduction and physical activity. Methods Studies of smartphone applications and text messaging interventions related to the cardiovascular risk factors of physical inactivity and overweight/obesity published between January 2005 and August 2010 were eligible. Studies related to disease management were excluded. Study characteristics and results were gathered and synthesized. Results A total of 36 citations from CINAHL, EMBASE, MEDLINE, PsyclNFO, and PubMed were identified; 7 articles were eligible for inclusion. The most frequent outcome measured in the studies was change in the weight of participants (57%). More than half of the studies (71%) reported statistically significant results in at least 1 outcome of weight loss, physical activity, dietary intake, decreased body mass index, decreased waist circumference, sugar-sweetened beverage intake, screen time, and satisfaction or acceptability outcomes. Conclusions All of the technology interventions that were supported by education or an additional intervention demonstrated a beneficial impact of text messaging or smartphone application for reduction of physical inactivity and/or overweight/obesity. More rigorous trials that determine what parts of the technology or intervention are effective as well as establishment of cost-effectiveness are necessary for further evaluation of smartphone and text messaging interventions. PMID:22635061

  4. Maternal immune activation increases seizure susceptibility in juvenile rat offspring.

    PubMed

    Yin, Ping; Zhang, Xin-Ting; Li, Jun; Yu, Lin; Wang, Ji-Wen; Lei, Ge-Fei; Sun, Ruo-Peng; Li, Bao-Min

    2015-06-01

    Epidemiological data suggest a relationship between maternal infection and a high incidence of childhood epilepsy in offspring. However, there is little experimental evidence that links maternal infection with later seizure susceptibility in juvenile offspring. Here, we asked whether maternal immune challenge during pregnancy can alter seizure susceptibility and seizure-associated brain damage in adolescence. Pregnant Sprague-Dawley rats were treated with lipopolysaccharide (LPS) or normal saline (NS) on gestational days 15 and 16. At postnatal day 21, seizure susceptibility to kainic acid (KA) was evaluated in male offspring. Four groups were studied, including normal control (NS-NS), prenatal infection (LPS-NS), juvenile seizure (NS-KA), and "two-hit" (LPS-KA) groups. Our results demonstrated that maternal LPS exposure caused long-term reactive astrogliosis and increased seizure susceptibility in juvenile rat offspring. Compared to the juvenile seizure group, animals in the "two-hit" group showed exaggerated astrogliosis, followed by worsened spatial learning ability in adulthood. In addition, prenatal immune challenge alone led to spatial learning impairment in offspring but had no effect on anxiety. These data suggest that prenatal immune challenge causes a long-term increase in juvenile seizure susceptibility and exacerbates seizure-induced brain injury, possibly by priming astroglia. PMID:25982885

  5. Activation of glucosidase via stress-induced polymerization rapidly increases active pools of abscisic acid.

    PubMed

    Lee, Kwang Hee; Piao, Hai Lan; Kim, Ho-Youn; Choi, Sang Mi; Jiang, Fan; Hartung, Wolfram; Hwang, Ildoo; Kwak, June M; Lee, In-Jung; Hwang, Inhwan

    2006-09-22

    Abscisic acid (ABA) is a phytohormone critical for plant growth, development, and adaptation to various stress conditions. Plants have to adjust ABA levels constantly to respond to changing physiological and environmental conditions. To date, the mechanisms for fine-tuning ABA levels remain elusive. Here we report that AtBG1, a beta-glucosidase, hydrolyzes glucose-conjugated, biologically inactive ABA to produce active ABA. Loss of AtBG1 causes defective stomatal movement, early germination, abiotic stress-sensitive phenotypes, and lower ABA levels, whereas plants with ectopic AtBG1 accumulate higher ABA levels and display enhanced tolerance to abiotic stress. Dehydration rapidly induces polymerization of AtBG1, resulting in a 4-fold increase in enzymatic activity. Furthermore, diurnal increases in ABA levels are attributable to polymerization-mediated AtBG1 activation. We propose that the activation of inactive ABA pools by polymerized AtBG1 is a mechanism by which plants rapidly adjust ABA levels and respond to changing environmental cues. PMID:16990135

  6. Traditional fermentation increases goitrogenic activity in pearl millet.

    PubMed

    Elnour, A; Liedén, S; Bourdoux, P; Eltom, M; Khalid, S A; Hambraeus, L

    1998-01-01

    Epidemiological evidence suggests that millet might play a role in the etiology of endemic goiter. Recently, we showed that a traditional fermentation procedure of two pearl millet (Pennisetum americanum L. Lecke) cultivars grown in Sudan modified their effects on the weight of the thyroid gland and thyroid hormone profile in rats. In the present study, we report that this fermentation procedure reduced the ash contents of millet by about 40% and removed considerable amounts of Mg (>50%), Zn (27-39%) and K (45%). Other minerals (Ca, Fe, Cu) were not affected. Feeding of one fermented cultivar resulted in significant reduction in bone Mg and Zn contents, whereas feeding of the other fermented cultivar resulted in reduction of bone Mg only. Dietary Mg intake and bone Mg contents correlated negatively with serum T3. Groups fed the millet diets had higher serum Se level compared to those fed wheat or casein diets and feeding of fermented millet resulted in a further increase in serum Se level. Thus our data indicate that in rats the enhanced effects of millet on the thyroid induced by fermentation is likely related to removal of minerals from millet and/or chemical transformation of the goitrogens contained in millet. PMID:9895422

  7. Increased Visual Stimulation Systematically Decreases Activity in Lateral Intermediate Cortex.

    PubMed

    Nasr, Shahin; Stemmann, Heiko; Vanduffel, Wim; Tootell, Roger B H

    2015-10-01

    Previous studies have attributed multiple diverse roles to the posterior superior temporal cortex (STC), both visually driven and cognitive, including part of the default mode network (DMN). Here, we demonstrate a unifying property across this multimodal region. Specifically, the lateral intermediate (LIM) portion of STC showed an unexpected feature: a progressively decreasing fMRI response to increases in visual stimulus size (or number). Such responses are reversed in sign, relative to well-known responses in classic occipital temporal visual cortex. In LIM, this "reversed" size function was present across multiple object categories and retinotopic eccentricities. Moreover, we found a significant interaction between the LIM size function and the distribution of subjects' attention. These findings suggest that LIM serves as a part of the DMN. Further analysis of functional connectivity, plus a meta-analysis of previous fMRI results, suggests that LIM is a heterogeneous area including different subdivisions. Surprisingly, analogous fMRI tests in macaque monkeys did not reveal a clear homolog of LIM. This interspecies discrepancy supports the idea that self-referential thinking and theory of mind are more prominent in humans, compared with monkeys. PMID:25480358

  8. Increased Visual Stimulation Systematically Decreases Activity in Lateral Intermediate Cortex

    PubMed Central

    Nasr, Shahin; Stemmann, Heiko; Vanduffel, Wim; Tootell, Roger B. H.

    2015-01-01

    Previous studies have attributed multiple diverse roles to the posterior superior temporal cortex (STC), both visually driven and cognitive, including part of the default mode network (DMN). Here, we demonstrate a unifying property across this multimodal region. Specifically, the lateral intermediate (LIM) portion of STC showed an unexpected feature: a progressively decreasing fMRI response to increases in visual stimulus size (or number). Such responses are reversed in sign, relative to well-known responses in classic occipital temporal visual cortex. In LIM, this “reversed” size function was present across multiple object categories and retinotopic eccentricities. Moreover, we found a significant interaction between the LIM size function and the distribution of subjects' attention. These findings suggest that LIM serves as a part of the DMN. Further analysis of functional connectivity, plus a meta-analysis of previous fMRI results, suggests that LIM is a heterogeneous area including different subdivisions. Surprisingly, analogous fMRI tests in macaque monkeys did not reveal a clear homolog of LIM. This interspecies discrepancy supports the idea that self-referential thinking and theory of mind are more prominent in humans, compared with monkeys. PMID:25480358

  9. In vitro synergistic anticancer activity of the combination of T-type calcium channel blocker and chemotherapeutic agent in A549 cells.

    PubMed

    Byun, Joon Seok; Sohn, Joo Mi; Leem, Dong Gyu; Park, Byeongyeon; Nam, Ji Hye; Shin, Dong Hyun; Shin, Ji Sun; Kim, Hyoung Ja; Lee, Kyung-Tae; Lee, Jae Yeol

    2016-02-01

    As a result of our continuous research, new 3,4-dihydroquinazoline derivative containing ureido group, KCP10043F was synthesized and evaluated for T-type Ca(2+) channel (Cav3.1) blockade, cytotoxicity, and cell cycle arrest against human non-small cell lung (A549) cells. KCP10043F showed both weaker T-type Ca(2+) channel blocking activity and less cytotoxicity against A549 cells than parent compound KYS05090S [4-(benzylcarbamoylmethyl)-3-(4-biphenylyl)-2-(N,N',N'-trimethyl-1,5-pentanediamino)-3,4-dihydroquinazoline 2 hydrochloride], but it exhibited more potent G1-phase arrest than KYS05090S in A549 cells. This was found to be accompanied by the downregulations of cyclin-dependent kinase (CDK) 2, CDK4, CDK6, cyclin D2, cyclin D3, and cyclin E at the protein levels. However, p27(KIP1) as a CDK inhibitor was gradually upregulated at the protein levels and increased recruitment to CDK2, CDK4 and CDK6 after KCP10043F treatment. Based on the strong G1-phase cell cycle arrest of KCP10043F in A549 cells, the combination of KCP10043F with etoposide (or cisplatin) resulted in a synergistic cell death (combination index=0.2-0.8) via the induction of apoptosis compared with either agent alone. Taken together with these overall results and the favorable in vitro ADME (absorption, distribution, metabolism, and excretion) profiles of KCP10043F, therefore, it could be used as a potential agent for the combination therapy on human lung cancer. PMID:26739776

  10. Development of a universal approach to increase physical activity among adolescents: the GoActive intervention

    PubMed Central

    Corder, Kirsten; Schiff, Annie; Kesten, Joanna M; van Sluijs, Esther M F

    2015-01-01

    Objectives To develop a physical activity (PA) promotion intervention for adolescents using a process addressing gaps in the literature while considering participant engagement. We describe the initial development stages; (1) existing evidence, (2) large scale opinion gathering and (3) developmental qualitative work, aiming (A) to gain insight into how to increase PA among the whole of year 9 (13–14 years-old) by identifying elements for intervention inclusion (B) to improve participant engagement and (C) to develop and refine programme design. Methods Relevant systematic reviews and longitudinal analyses of change were examined. An intervention was developed iteratively with older adolescents (17.3±0.5 years) and teachers, using the following process: (1) focus groups with (A) adolescents (n=26) and (B) teachers (n=4); (2) individual interviews (n=5) with inactive and shy adolescents focusing on engagement and programme acceptability. Qualitative data were analysed thematically. Results Limitations of the existing literature include lack of evidence on whole population approaches, limited adolescent involvement in intervention development, and poor participant engagement. Qualitative work suggested six themes which may encourage adolescents to do more PA; choice, novelty, mentorship, competition, rewards and flexibility. Teachers discussed time pressures as a barrier to encouraging adolescent PA and suggested between-class competition as a strategy. GoActive aims to increase PA through increased peer support, self-efficacy, group cohesion, self-esteem and friendship quality, and is implemented in tutor groups using a student-led tiered-leadership system. Conclusions We have followed an evidence-based iterative approach to translate existing evidence into an adolescent PA promotion intervention. Qualitative work with adolescents and teachers supported intervention design and addressed lack of engagement with health promotion programmes within this age group

  11. Playground Designs to Increase Physical Activity Levels during School Recess: A Systematic Review

    ERIC Educational Resources Information Center

    Escalante, Yolanda; García-Hermoso, Antonio; Backx, Karianne; Saavedra, Jose M.

    2014-01-01

    School recess provides a major opportunity to increase children's physical activity levels. Various studies have described strategies to increase levels of physical activity. The purpose of this systematic review is therefore to examine the interventions proposed as forms of increasing children's physical activity levels during recess. A…

  12. GW8510 Increases Insulin Expression in Pancreatic Alpha Cells through Activation of p53 Transcriptional Activity

    PubMed Central

    Fomina-Yadlin, Dina; Kubicek, Stefan; Vetere, Amedeo; He, Kaihui Hu; Schreiber, Stuart L.; Wagner, Bridget K.

    2012-01-01

    Background Expression of insulin in terminally differentiated non-beta cell types in the pancreas could be important to treating type-1 diabetes. Previous findings led us to hypothesize involvement of kinase inhibition in induction of insulin expression in pancreatic alpha cells. Methodology/Principal Findings Alpha (αTC1.6) cells and human islets were treated with GW8510 and other small-molecule inhibitors for up to 5 days. Alpha cells were assessed for gene- and protein-expression levels, cell-cycle status, promoter occupancy status by chromatin immunoprecipitation (ChIP), and p53-dependent transcriptional activity. GW8510, a putative CDK2 inhibitor, up-regulated insulin expression in mouse alpha cells and enhanced insulin secretion in dissociated human islets. Gene-expression profiling and gene-set enrichment analysis of GW8510-treated alpha cells suggested up-regulation of the p53 pathway. Accordingly, the compound increased p53 transcriptional activity and expression levels of p53 transcriptional targets. A predicted p53 response element in the promoter region of the mouse Ins2 gene was verified by chromatin immunoprecipitation (ChIP). Further, inhibition of Jun N-terminal kinase (JNK) and p38 kinase activities suppressed insulin induction by GW8510. Conclusions/Significance The induction of Ins2 by GW8510 occurred through p53 in a JNK- and p38-dependent manner. These results implicate p53 activity in modulation of Ins2 expression levels in pancreatic alpha cells, and point to a potential approach toward using small molecules to generate insulin in an alternative cell type. PMID:22242153

  13. Increased Biomass Yield of Lactococcus lactis by Reduced Overconsumption of Amino Acids and Increased Catalytic Activities of Enzymes

    PubMed Central

    Adamberg, Kaarel; Seiman, Andrus; Vilu, Raivo

    2012-01-01

    Steady state cultivation and multidimensional data analysis (metabolic fluxes, absolute proteome, and transcriptome) are used to identify parameters that control the increase in biomass yield of Lactococcus lactis from 0.10 to 0.12 C-mol C-mol−1 with an increase in specific growth rate by 5 times from 0.1 to 0.5 h−1. Reorganization of amino acid consumption was expressed by the inactivation of the arginine deiminase pathway at a specific growth rate of 0.35 h−1 followed by reduced over-consumption of pyruvate directed amino acids (asparagine, serine, threonine, alanine and cysteine) until almost all consumed amino acids were used only for protein synthesis at maximal specific growth rate. This balanced growth was characterized by a high glycolytic flux carrying up to 87% of the carbon flow and only amino acids that relate to nucleotide synthesis (glutamine, serine and asparagine) were consumed in higher amounts than required for cellular protein synthesis. Changes in the proteome were minor (mainly increase in the translation apparatus). Instead, the apparent catalytic activities of enzymes and ribosomes increased by 3.5 times (0.1 vs 0.5 h−1). The apparent catalytic activities of glycolytic enzymes and ribosomal proteins were seen to follow this regulation pattern while those of enzymes involved in nucleotide metabolism increased more than the specific growth rate (over 5.5 times). Nucleotide synthesis formed the most abundant biomonomer synthetic pathway in the cells with an expenditure of 6% from the total ATP required for biosynthesis. Due to the increase in apparent catalytic activity, ribosome translation was more efficient at higher growth rates as evidenced by a decrease of protein to mRNA ratios. All these effects resulted in a 30% decrease of calculated ATP spilling (0.1 vs 0.5 h−1). Our results show that bioprocesses can be made more efficient (using a balanced metabolism) by varying the growth conditions. PMID:23133574

  14. Increased hepcidin in transferrin-treated thalassemic mice correlates with increased liver BMP2 expression and decreased hepatocyte ERK activation

    PubMed Central

    Chen, Huiyong; Choesang, Tenzin; Li, Huihui; Sun, Shuming; Pham, Petra; Bao, Weili; Feola, Maria; Westerman, Mark; Li, Guiyuan; Follenzi, Antonia; Blanc, Lionel; Rivella, Stefano; Fleming, Robert E.; Ginzburg, Yelena Z.

    2016-01-01

    Iron overload results in significant morbidity and mortality in β-thalassemic patients. Insufficient hepcidin is implicated in parenchymal iron overload in β-thalassemia and approaches to increase hepcidin have therapeutic potential. We have previously shown that exogenous apo-transferrin markedly ameliorates ineffective erythropoiesis and increases hepcidin expression in Hbbth1/th1 (thalassemic) mice. We utilize in vivo and in vitro systems to investigate effects of exogenous apo-transferrin on Smad and ERK1/2 signaling, pathways that participate in hepcidin regulation. Our results demonstrate that apo-transferrin increases hepcidin expression in vivo despite decreased circulating and parenchymal iron concentrations and unchanged liver Bmp6 mRNA expression in thalassemic mice. Hepatocytes from apo-transferrin-treated mice demonstrate decreased ERK1/2 pathway and increased serum BMP2 concentration and hepatocyte BMP2 expression. Furthermore, hepatocyte ERK1/2 phosphorylation is enhanced by neutralizing anti-BMP2/4 antibodies and suppressed in vitro in a dose-dependent manner by BMP2, resulting in converse effects on hepcidin expression, and hepatocytes treated with MEK/ERK1/2 inhibitor U0126 in combination with BMP2 exhibit an additive increase in hepcidin expression. Lastly, bone marrow erythroferrone expression is normalized in apo-transferrin treated thalassemic mice but increased in apo-transferrin injected wild-type mice. These findings suggest that increased hepcidin expression after exogenous apo-transferrin is in part independent of erythroferrone and support a model in which apo-transferrin treatment in thalassemic mice increases BMP2 expression in the liver and other organs, decreases hepatocellular ERK1/2 activation, and increases nuclear Smad to increase hepcidin expression in hepatocytes. PMID:26635037

  15. [Adaptive increase of serotonergic system activity in tissues of half-migratory and migratory fish at increased water salinity].

    PubMed

    2013-01-01

    The article deals with studies of the serotoninergic system activity in different tissues of half-migratory fish--the Caspian roach (Rutilus rutilus caspicus) and carpbream (Abramis brama orientalis)--and migratory fish--shemaya (Chalcalburnus chalcoides) caught in fresh and brackish waters, as well as in the common carp (Cyprinus carpio L.) tissues under effect of brackish water in model experiments. Using indirect solid-phase ELISA-test, the serotoninergic system activity was evaluated by measuring in the tissues of the studied fish the serotonin-modulated anticonsolidation protein (SMAP) which is in linear relationship with serotonin level. There was found a significant elevation of the SMAP levels in the brain of the Caspian roach, carpbream, shemaya, and the common carp under effect of increased water sainity. The revealed increase of the SMAP content in brains of the Caspian roach, carpbream, shemaya, and the common carp under action of increased water salinity reflects the corresponding elevated activity of the serotoninergic system and indicates involvement of adaptive readjustments in the animals' body. PMID:25509051

  16. [Adaptive increase of serotonergic system activity in tissues of half-migratory and migratory fish at increased water salinity].

    PubMed

    Mustafaev, N J; Mekhtiev, A A

    2013-01-01

    The article deals with studies of the serotoninergic system activity in different tissues of half-migratory fish--the Caspian roach (Rutilus rutilus caspicus) and carpbream (Abramis brama orientalis)--and migratory fish--shemaya (Chalcalburnus chalcoides) caught in fresh and brackish waters, as well as in the common carp (Cyprinus carpio L.) tissues under effect of brackish water in model experiments. Using indirect solid-phase ELISA-test, the serotoninergic system activity was evaluated by measuring in the tissues of the studied fish the serotonin-modulated anticonsolidation protein (SMAP) which is in linear relationship with serotonin level. There was found a significant elevation of the SMAP levels in the brain of the Caspian roach, carpbream, shemaya, and the common carp under effect of increased water sainity. The revealed increase of the SMAP content in brains of the Caspian roach, carpbream, shemaya, and the common carp under action of increased water salinity reflects the corresponding elevated activity of the serotoninergic system and indicates involvement of adaptive readjustments in the animals' body. PMID:25490850

  17. Community-based exergaming program increases physical activity and perceived wellness in older adults.

    PubMed

    Strand, Kara A; Francis, Sarah L; Margrett, Jennifer A; Franke, Warren D; Peterson, Marc J

    2014-07-01

    Exergaming may be an effective strategy to increase physical activity participation among rural older adults. This pilot project examined the effects of a 24-wk exergaming and wellness program (8 wk onsite exergaming, 16-wk wellness newsletter intervention) on physical activity participation and subjective health in 46 rural older adults. Sociodemographic data and self-reported physical activity were analyzed using descriptive statistics and Cochran's Q, respectively. Qualitative data were reviewed, categorized on the basis of theme, and tabulated for frequency. Increased physical activity and perceived health were the most reported perceived positive changes. Significant increases in physical activity participation were maintained among participants who were physically inactive at baseline. Best-liked features were physical activity and socialization. Findings suggest that this pilot exergaming and wellness program is effective in increasing physical activity in sedentary rural older adults, increasing socialization, and increasing subjective physical health among rural older adults. PMID:23945726

  18. The effect of increasing autonomy through choice on young children’s physical activity behavior

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Increasing autonomy by manipulating the choice of available physical activity options in a laboratory setting can increase physical activity in older children and adults. However, the effect of manipulating the number of physically active choices has yet to be examined in young children in a gymnas...

  19. Promising School-Based Strategies and Intervention Guidelines to Increase Physical Activity of Adolescents

    ERIC Educational Resources Information Center

    Pardo, Berta Murillo; Bengoechea, Enrique Garcia; Lanaspa, Eduardo Generelo; Bush, Paula L.; Casterad, Javier Zaragoza; Clemente, Jose A. Julian; Gonzalez, Luis Garcia

    2013-01-01

    This narrative review describes the available scientific evidence regarding promising school-based strategies to increase physical activity of adolescents. We conducted a literature search for studies published up to 2011, regarding adolescent physical activity intervention studies that resulted in increased physical activity (regardless of…

  20. Patchouli alcohol, an essential oil of Pogostemon cablin, exhibits anti-tumorigenic activity in human colorectal cancer cells.

    PubMed

    Jeong, Jin Boo; Choi, Jieun; Lou, Zhiyuan; Jiang, Xiaojing; Lee, Seong-Ho

    2013-06-01

    Patchouli alcohol (PA) is one of the important compounds isolated from the essential oil of Pogostemon cablin (patchouli). PA has neuroprotective, anti-influenza and anti-inflammatory activities. However, anti-cancer activity of PA has not been studied so far. We performed in vitro study to investigate whether PA affects proliferation and apoptosis of human colorectal cancer cells, and to define potential molecular mechanisms. PA suppressed cell growth and induced apoptosis in a dose-dependent manner in human colorectal cancer cells (HCT116, SW480). In addition, PA decreased cell growth in MCF7, BxPC3, PC3, and HUVEC cells. Exposure of PA to HCT116 and SW480 cells activated p21 expression and suppressed the expressions of cyclin D1 and cyclin-dependent kinase 4 (CDK4) in a dose-dependent manner. In addition, PA attenuated the expressions of HDAC2 (histone deacetylase 2) and c-myc, and HDAC enzyme activity. We also observed that PA induced the transcriptional activity of NF-κB through an increase of nuclear translocation of p65. These findings suggest that PA exerts an anti-cancer activity by decreasing cell growth and increasing apoptosis in human colorectal cancer cells. The proposed mechanisms include the inhibition of HDAC2 expression and HDAC enzyme activity, and subsequent downregulation of c-myc and activation of NF-κB pathway. PMID:23602914

  1. Vitamin E supplementation increases the resistance of both LDL and HDL to oxidation and increases cholesteryl ester transfer activity.

    PubMed

    Arrol, S; Mackness, M I; Durrington, P N

    2000-05-01

    There is increasing evidence that lipid peroxidation and oxidative modification of low density lipoprotein (LDL) is important in atherogenesis. Evidence that antioxidant therapy decreases mortality is, however, inconclusive. We have examined the effects of vitamin E on the susceptibility of LDL and high density lipoprotein (HDL) to oxidation, and on cholesteryl ester heteroexchange in an in vitro system using autologous serum lipoproteins. Vitamin E in doses of 200 and 400 mg/day were administered orally to 21 healthy volunteers (12 females and nine males) aged between 23 and 50 years, and to 16 healthy volunteers (eight females and eight males) aged between 22 and 51 years for 50 days, respectively. Fasting serum lipoproteins, susceptibility of lipoproteins to oxidation and cholesteryl ester transfer activity (CETA) were measured before and after vitamin E supplementation. Serum lipoprotein and lipid concentrations did not change significantly in either group. The LDL-conjugated diene (CD) lag phase during incubation with Cu(2+) was increased by 157% (110-232%) (median (interquartile range)) (P<0.05) on vitamin E (200 mg/day) and by 235% (185-259%) (P<0.0001) on 400 mg/day. The lag phases for LDL-lipid peroxide (LPO) generation were also significantly increased by 146% (122-192%) (P<0.005) and 177% (101-267%) (P<0.005), respectively. The HDL-CD lag phase also increased on both doses 140% (115-169%) (P<0.005) and 171% (122-192%) (P<0.005), as did the HDL-LPO lag phase by 123% (104-153%) (P<0.05) on 200 mg/day and 240% (97-360%) (P<0.005) on 400 mg daily. Cholesteryl ester transfer activity from HDL to very low and low density lipoproteins significantly increased from 12. 7+/-2.6 (mean+/-SEM) to 16+/-3.4 nmol/ml/h (P<0.05) on 200 mg/daily and 10.4+/-2.0 to 19.2+/-3.3 nmol/ml/h (P<0.005) on vitamin E, 400mg day. Thus, vitamin E (200 and 400mg daily) significantly decreased the susceptibility of LDL and HDL to oxidation in vitro. However, the increase in CETA

  2. Runx1 Phosphorylation by Src Increases Trans-activation via Augmented Stability, Reduced Histone Deacetylase (HDAC) Binding, and Increased DNA Affinity, and Activated Runx1 Favors Granulopoiesis.

    PubMed

    Leong, Wan Yee; Guo, Hong; Ma, Ou; Huang, Hui; Cantor, Alan B; Friedman, Alan D

    2016-01-01

    Src phosphorylates Runx1 on one central and four C-terminal tyrosines. We find that activated Src synergizes with Runx1 to activate a Runx1 luciferase reporter. Mutation of the four Runx1 C-terminal tyrosines to aspartate or glutamate to mimic phosphorylation increases trans-activation of the reporter in 293T cells and allows induction of Cebpa or Pu.1 mRNAs in 32Dcl3 myeloid cells, whereas mutation of these residues to phenylalanine to prevent phosphorylation obviates these effects. Three mechanisms contribute to increased Runx1 activity upon tyrosine modification as follows: increased stability, reduced histone deacetylase (HDAC) interaction, and increased DNA binding. Mutation of the five modified Runx1 tyrosines to aspartate markedly reduced co-immunoprecipitation with HDAC1 and HDAC3, markedly increased stability in cycloheximide or in the presence of co-expressed Cdh1, an E3 ubiquitin ligase coactivator, with reduced ubiquitination, and allowed DNA-binding in gel shift assay similar to wild-type Runx1. In contrast, mutation of these residues to phenylalanine modestly increased HDAC interaction, modestly reduced stability, and markedly reduced DNA binding in gel shift assays and as assessed by chromatin immunoprecipitation with the -14-kb Pu.1 or +37-kb Cebpa enhancers after stable expression in 32Dcl3 cells. Affinity for CBFβ, the Runx1 DNA-binding partner, was not affected by these tyrosine modifications, and in vitro translated CBFβ markedly increased DNA affinity of both the translated phenylalanine and aspartate Runx1 variants. Finally, further supporting a positive role for Runx1 tyrosine phosphorylation during granulopoiesis, mutation of the five Src-modified residues to aspartate but not phenylalanine allows Runx1 to increase Cebpa and granulocyte colony formation by Runx1-deleted murine marrow. PMID:26598521

  3. Increasing Physical Activity during the School Day through Physical Activity Classes: Implications for Physical Educators

    ERIC Educational Resources Information Center

    Adkins, Megan; Bice, Matt; Bartee, Todd; Heelan, Kate

    2015-01-01

    Across the nation schools are adopting health and wellness policies, specifically physical activity (PA) initiatives that aid healthy long-term lifestyles. Interest has been generated about the inclusion of physical activity classes to complement existing physical education classes. Furthermore, discussion has evolved as to if additional…

  4. Connecting active living research and public policy: transdisciplinary research and policy interventions to increase physical activity.

    PubMed

    Schilling, Joseph M; Giles-Corti, Billie; Sallis, James F

    2009-01-01

    National and international organizations recommend creation of environments that support physical activity where people live, work, play, study, and travel. Policy changes can lead to activity-supportive environments and incentives. Research on environmental and policy influences on physical activity is well underway in many countries. An important use of the research is to inform policy debates, but the "translation" of research to policy is an emerging science. The papers in this supplement were presented at the 2008 Active Living Research Conference whose theme was "Connecting Active Living Research to Policy Solutions." The papers include evaluations of policy initiatives and research that suggests promising new policies. Commentaries propose principles for improving the translation of research to policy. Improving the rigor of research, asking policy-relevant questions, presenting country-specific data, and effectively communicating findings to policy makers are likely to contribute to greater impact of research on policy processes. PMID:19190567

  5. Decreasing Stereotypy in Preschoolers with Autism Spectrum Disorder: The Role of Increased Physical Activity and Function

    ERIC Educational Resources Information Center

    McLaughlin, Constance Ann Hylton

    2010-01-01

    This study used increased physical activity during recess to reduce stereotypy in preschoolers with Autism Spectrum Disorder. Results indicate increasing physical activity can be used as an intervention to reduce automatically maintained stereotypy in preschoolers with ASD. The intervention had a lesser effect on a preschooler whose stereotypy was…

  6. 26 CFR 1.280C-4 - Credit for increasing research activities.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 26 Internal Revenue 3 2011-04-01 2011-04-01 false Credit for increasing research activities. 1... increasing research activities. (a) In general. The election under section 280C(c)(3) to have the provisions... 41(a) determined by the method provided in section 280C(c)(3)(B) on an original return for...

  7. Evidence-Based Practice Guideline: Increasing Physical Activity in Schools--Kindergarten through 8th Grade

    ERIC Educational Resources Information Center

    Bagby, Karen; Adams, Susan

    2007-01-01

    Because of the growing obesity epidemic across all age groups in the United States, interventions to increase physical activity and reduce sedentary behaviors have become a priority. Evidence is growing that interventions to increase physical activity and reduce sedentary behaviors have positive results and are generally inexpensive to implement.…

  8. Men on the Move: A Pilot Program to Increase Physical Activity among African American Men

    ERIC Educational Resources Information Center

    Griffith, Derek M.; Allen, Julie Ober; Johnson-Lawrence, Vicki; Langford, Aisha

    2014-01-01

    Despite the important contribution increasing physical activity levels may play in reducing chronic disease morbidity and mortality, there is a paucity of interventions and research indicating how to improve physical activity levels in African American men. "Men on the Move" was a pilot study to increase African American men's…

  9. Increasing Activity Attendance and Engagement in Individuals with Dementia Using Descriptive Prompts

    ERIC Educational Resources Information Center

    Brenske, Shasta; Rudrud, Eric H.; Schulze, Kimberly A.; Rapp, John T.

    2008-01-01

    The effects of providing descriptive prompts to increase activity attendance and engagement in 6 individuals with dementia were evaluated using a reversal design. The results showed that providing descriptive prompts increased activity attendance and engagement for all participants. The results support the use of antecedent interventions for…

  10. 26 CFR 1.41-1 - Credit for increasing research activities.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 26 Internal Revenue 1 2011-04-01 2009-04-01 true Credit for increasing research activities. 1.41-1... TAXES Credits Against Tax § 1.41-1 Credit for increasing research activities. (a) Amount of credit. The...). (b) Introduction to regulations under section 41. (1) Sections 1.41-2 through 1.41-8 and...

  11. 26 CFR 1.41-1 - Credit for increasing research activities.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 1 2010-04-01 2010-04-01 true Credit for increasing research activities. 1.41-1... TAXES Credits Against Tax § 1.41-1 Credit for increasing research activities. (a) Amount of credit. The...). (b) Introduction to regulations under section 41. (1) Sections 1.41-2 through 1.41-8 and...

  12. Evidence-based practice guideline: increasing physical activity in schools--kindergarten through 8th grade.

    PubMed

    Bagby, Karen; Adams, Susan

    2007-06-01

    Because of the growing obesity epidemic across all age groups in the United States, interventions to increase physical activity and reduce sedentary behaviors have become a priority. Evidence is growing that interventions to increase physical activity and reduce sedentary behaviors have positive results and are generally inexpensive to implement. National and international health organizations are calling for a comprehensive approach for reducing obesity in children that includes increasing physical activity in the school setting. Although the call to increase activity levels in schools is clear, little guidance has been given to schools on specific methods to accomplish this task. This article provides an overview of an evidence-based guideline developed by a physical education teacher and a school nurse to provide inexpensive, easy-to-implement, effective strategies to increase physical activity in students. Tools are also included in the guideline to measure the effectiveness of the intervention. PMID:17536917

  13. Use of an open-loop system to increase physical activity

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study evaluated the effectiveness of an open-loop system that reinforces physical activity with TV watching to increase children’s physical activity. Non-overweight, sedentary boys and girls (8-12 y) were randomized to a group that received feedback of activity counts + reinforcement for physic...

  14. Person-Centred Active Support--Increasing Choice, Promoting Independence and Reducing Challenging Behaviour

    ERIC Educational Resources Information Center

    Beadle-Brown, Julie; Hutchinson, Aislinn; Whelton, Beckie

    2012-01-01

    Background: Previous research has found that active support is effective at increasing levels of participation in activities and supporting a good quality of life for people with intellectual disabilities. However, there has been little research on the effect of active support on other outcome measures. Methods: This study uses observational…

  15. Texting to increase physical activity among teenagers (TXT Me!): Rationale, design, and methods proposal

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Physical activity decreases from childhood through adulthood. Among youth, teenagers (teens) achieve the lowest levels of physical activity, and high school age youth are particularly at risk of inactivity. Effective methods are needed to increase youth physical activity in a way that can be maintai...

  16. Botulinum toxin complex increases paracellular permeability in intestinal epithelial cells via activation of p38 mitogen-activated protein kinase.

    PubMed

    Miyashita, Shin-Ichiro; Sagane, Yoshimasa; Inui, Ken; Hayashi, Shintaro; Miyata, Keita; Suzuki, Tomonori; Ohyama, Tohru; Watanabe, Toshihiro; Niwa, Koichi

    2013-12-30

    Clostridium botulinum produces a large toxin complex (L-TC) that increases paracellular permeability in intestinal epithelial cells by a mechanism that remains unclear. Here, we show that mitogen-activated protein kinases (MAPKs) are involved in this permeability increase. Paracellular permeability was measured by FITC-dextran flux through a monolayer of rat intestinal epithelial IEC-6 cells, and MAPK activation was estimated from western blots. L-TC of C. botulinum serotype D strain 4947 increased paracellular dextran flux and activated extracellular signal-regulated kinase (ERK), p38, but not c-Jun N-terminal kinase (JNK) in IEC-6 cells. The permeability increase induced by L-TC was abrogated by the p38 inhibitor SB203580. These results indicate that L-TC increases paracellular permeability by activating p38, but not JNK and ERK. PMID:23884081

  17. Longterm persistence of proteolytic activities in frass of Blattella germanica increases its allergenic potential.

    PubMed

    Erban, T; Hubert, J

    2011-06-01

    Chromogenic microplate assays in 96 wells were used to determine the stability of enzyme activity in frass of Blattella germanica (Blattodea: Blattellidae). Frass samples were exposed to controlled conditions [temperature 15-35 °C and/or 53-100% relative humidity (RH)] and to household conditions (apartment). Exposure times were 0 (control), 90, 183 and 276 days. Starch digestion and cellulolytic activities decreased during exposure. Non-specific proteolytic activities were affected by changes in selective proteolytic activities. Activities towards AAPpNA and SA(3) pNA strongly increased at 100% RH, indicating the possible influence of microorganisms growing on frass. Activities towards BApNA and ArgpNA decreased with increasing decomposition time, whereas activity towards ZRRpNA was not influenced by exposure time. The largest decrease in activities towards ArgpNA and BApNA occurred at temperatures of 15 °C, 30 °C and 35 °C and at 100% RH. Activities towards BApNA and ZRRpNA were very stable under different temperature and RH conditions; this was confirmed by findings showing that these activities were stable in the experimental apartment. In comparison with the control, activities towards ZRRpNA and BApNA after 276 days decreased by 1% and 19%, respectively. The longterm persistence of proteolytic activities in cockroach frass increases their allergenic hazard potential. PMID:21198710

  18. Vertebrate blood cell volume increases with temperature: implications for aerobic activity

    PubMed Central

    Zenil-Ferguson, Rosana

    2014-01-01

    Aerobic activity levels increase with body temperature across vertebrates. Differences in these levels, from highly active to sedentary, are reflected in their ecology and behavior. Yet, the changes in the cardiovascular system that allow for greater oxygen supply at higher temperatures, and thus greater aerobic activity, remain unclear. Here we show that the total volume of red blood cells in the body increases exponentially with temperature across vertebrates, after controlling for effects of body size and taxonomy. These changes are accompanied by increases in relative heart mass, an indicator of aerobic activity. The results point to one way vertebrates may increase oxygen supply to meet the demands of greater activity at higher temperatures. PMID:24765580

  19. The Bile Acid Chenodeoxycholic Acid Increases Human Brown Adipose Tissue Activity.

    PubMed

    Broeders, Evie P M; Nascimento, Emmani B M; Havekes, Bas; Brans, Boudewijn; Roumans, Kay H M; Tailleux, Anne; Schaart, Gert; Kouach, Mostafa; Charton, Julie; Deprez, Benoit; Bouvy, Nicole D; Mottaghy, Felix; Staels, Bart; van Marken Lichtenbelt, Wouter D; Schrauwen, Patrick

    2015-09-01

    The interest in brown adipose tissue (BAT) as a target to combat metabolic disease has recently been renewed with the discovery of functional BAT in humans. In rodents, BAT can be activated by bile acids, which activate type 2 iodothyronine deiodinase (D2) in BAT via the G-coupled protein receptor TGR5, resulting in increased oxygen consumption and energy expenditure. Here we examined the effects of oral supplementation of the bile acid chenodeoxycholic acid (CDCA) on human BAT activity. Treatment of 12 healthy female subjects with CDCA for 2 days resulted in increased BAT activity. Whole-body energy expenditure was also increased upon CDCA treatment. In vitro treatment of primary human brown adipocytes derived with CDCA or specific TGR5 agonists increased mitochondrial uncoupling and D2 expression, an effect that was absent in human primary white adipocytes. These findings identify bile acids as a target to activate BAT in humans. PMID:26235421

  20. Diabetes or peroxisome proliferator-activated receptor alpha agonist increases mitochondrial thioesterase I activity in heart

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Peroxisome proliferator-activated receptor alpha (PPAR alpha) is a transcriptional regulator of the expression of mitochondrial thioesterase I (MTE-I) and uncoupling protein 3 (UCP3), which are induced in the heart at the mRNA level in response to diabetes. Little is known about the regulation of pr...

  1. Feasibility and Effects of Short Activity Breaks for Increasing Preschool-Age Children's Physical Activity Levels

    ERIC Educational Resources Information Center

    Alhassan, Sofiya; Nwaokelemeh, Ogechi; Mendoza, Albert; Shitole, Sanyog; Puleo, Elaine; Pfeiffer, Karin A.; Whitt-Glover, Melicia C.

    2016-01-01

    Background: We examined the effects of short bouts of structured physical activity (SBS-PA) implemented within the classroom setting as part of designated gross-motor playtime on preschoolers PA. Methods: Preschools were randomized to SBS-PA (centers, N = 5; participants, N = 141) or unstructured free playtime (UPA) (centers, N = 5; participants,…

  2. Fas-Induced Apoptosis Increases Hepatocyte Tissue Factor Procoagulant Activity In Vitro and In Vivo

    PubMed Central

    Lopez, Michelle; Kopec, Anna K.; Joshi, Nikita; Geddings, Julia E.; Cline, Holly; Towery, Keara L.; Rockwell, Cheryl E.; Mackman, Nigel; Luyendyk, James P.

    2014-01-01

    Hepatocyte (HPC) apoptosis occurs in association with hepatotoxic responses and chronic liver disease, and is coupled to activation of the blood coagulation cascade. HPCs have been shown to express tissue factor (TF), the primary activator of blood coagulation, in a form that lacks procoagulant activity. In this study, we determined the effect of inducing HPC apoptosis on the procoagulant activity of TF. Treatment of primary mouse HPCs with the Fas death receptor agonist (anti-CD95 antibody, Jo2) triggered apoptosis as shown by cleavage of caspase-3, increased caspase-3 proteolytic activity, and cell surface exposure of phosphatidylserine (PS). Jo2-induced apoptosis significantly increased TF-dependent factor Xa generation by HPCs. Moreover, Jo2 treatment was associated with increased levels of microparticle-associated TF procoagulant activity in the culture medium. Pretreatment with a caspase-3 inhibitor significantly reduced Jo2-induced HPC TF activity and prevented the increase in microparticle-associated TF procoagulant activity. Application of the high-affinity PS-binding protein lactadherin inhibited TF-dependent factor Xa generation by Jo2-treated HPCs and dramatically reduced microparticle-associated TF procoagulant activity. Treatment of wild-type mice with a sublethal dose of Jo2 was associated with a robust increase in the activation of coagulation as measured by plasma thrombin-antithrombin (TAT) levels; whereas mice with liver-specific TF deficiency had significantly lower TAT levels. Overall, the results indicate that Fas-initiated, caspase-3-dependent HPC apoptosis increases TF procoagulant activity through a mechanism involving PS externalization. This suggests that activation of liver TF likely contributes to the procoagulant state associated with HPC apoptosis in liver toxicity and disease. PMID:25015658

  3. Simulated ischaemia-reperfusion conditions increase xanthine dehydrogenase and oxidase activities in rat brain slices.

    PubMed

    Battelli, M G; Buonamici, L; Virgili, M; Abbondanza, A; Contestabile, A

    1998-01-01

    Xanthine dehydrogenase and oxidase activities increased by 87% in rat brain slices after 30 min in vitro ischaemia. A further 41% increase was induced by 30 min simulated reperfusion of ischaemic slices. No conversion from the dehydrogenase to the oxidase activity was observed. The increment of enzyme activity was not due to neosynthesis of the enzyme, since it was not affected by the addition of cycloheximide during the ischaemic incubation. The increased oxygen-dependent form of the enzyme could aggravate the ischaemic brain injury by free radicals production, in particular after reperfusion. PMID:9460697

  4. The rate of synthesis and decomposition of tissue proteins in hypokinesia and increased muscular activity

    NASA Technical Reports Server (NTRS)

    Fedorov, I. V.; Chernyy, A. V.; Fedorov, A. I.

    1978-01-01

    During hypokinesia and physical loading (swimming) of rats, the radioactivity of skeletal muscle, liver, kidney, heart, and blood proteins was determined after administration of radioactive amino acids. Tissue protein synthesis decreased during hypokinesia, and decomposition increased. Both synthesis and decomposition increased during physical loading, but anabolic processes predominated in the total tissue balance. The weights of the animals decreased in hypokinesia and increased during increased muscle activity.

  5. Lung cancer chemotherapy agents increase procoagulant activity via protein disulfide isomerase-dependent tissue factor decryption.

    PubMed

    Lysov, Zakhar; Swystun, Laura L; Kuruvilla, Sara; Arnold, Andrew; Liaw, Patricia C

    2015-01-01

    Lung cancer patients undergoing chemotherapy have an elevated risk for thrombosis. However, the mechanisms by which chemotherapy agents increase the risk for thrombosis remains unclear. The aim of this study was to determine the mechanism(s) by which lung cancer chemotherapy agents cisplatin, carboplatin, gemcitabine, and paclitaxel elicit increased tissue factor activity on endothelial cells, A549 cells, and monocytes. Tissue factor activity, tissue factor antigen, and phosphatidylserine exposure were measured on chemotherapy-treated human umbilical vein endothelial cells (HUVEC), A549 cells, and monocytes. Cell surface protein disulfide isomerase (PDI) and cell surface free thiol levels were measured on HUVEC and A549 non-small cell lung carcinoma cells. Treatment of HUVECs, A549 cells, and monocytes with lung cancer chemotherapy significantly increased cell surface tissue factor activity. However, elevated tissue factor antigen levels were observed only on cisplatin-treated and gemcitabine-treated monocytes. Cell surface levels of phosphatidylserine were increased on HUVEC and monocytes treated with cisplatin/gemcitabine combination therapy. Chemotherapy also resulted in increased cell surface levels of PDI and reduced cell surface free thiol levels. Glutathione treatment and PDI inhibition, but not phosphatidylserine inhibition, attenuated tissue factor activity. Furthermore, increased tissue factor activity was reversed by reducing cysteines with dithiothreitol. These studies are the first to demonstrate that lung cancer chemotherapy agents increase procoagulant activity on endothelial cells and A549 cells by tissue factor decryption through a disulfide bond formation in a PDI-dependent mechanism. PMID:24911456

  6. Clinical hypothermia temperatures increase complement activation and cell destruction via the classical pathway

    PubMed Central

    2014-01-01

    Background Therapeutic hypothermia is a treatment modality that is increasingly used to improve clinical neurological outcomes for ischemia-reperfusion injury-mediated diseases. Antibody-initiated classical complement pathway activation has been shown to contribute to ischemia-reperfusion injury in multiple disease processes. However, how therapeutic hypothermia affects complement activation is unknown. Our goal was to measure the independent effect of temperature on complement activation, and more specifically, examine the relationship between clinical hypothermia temperatures (31–33°C), and complement activation. Methods Antibody-sensitized erythrocytes were used to assay complement activation at temperatures ranging from 0-41°C. Individual complement pathway components were assayed by ELISA, Western blot, and quantitative dot blot. Peptide Inhibitor of complement C1 (PIC1) was used to specifically inhibit activation of C1. Results Antibody-initiated complement activation resulting in eukaryotic cell lysis was increased by 2-fold at 31°C compared with 37°C. Antibody-initiated complement activation in human serum increased as temperature decreased from 37°C until dramatically decreasing at 13°C. Quantitation of individual complement components showed significantly increased activation of C4, C3, and C5 at clinical hypothermia temperatures. In contrast, C1s activation by heat-aggregated IgG decreased at therapeutic hypothermia temperatures consistent with decreased enzymatic activity at lower temperatures. However, C1q binding to antibody-coated erythrocytes increased at lower temperatures, suggesting that increased classical complement pathway activation is mediated by increased C1 binding at therapeutic hypothermia temperatures. PIC1 inhibited hypothermia-enhanced complement-mediated cell lysis at 31°C by up to 60% (P = 0.001) in a dose dependent manner. Conclusions In summary, therapeutic hypothermia temperatures increased antibody

  7. Increasing Spontaneous Retinal Activity before Eye Opening Accelerates the Development of Geniculate Receptive Fields

    PubMed Central

    Davis, Zachary W.; Chapman, Barbara

    2015-01-01

    Visually evoked activity is necessary for the normal development of the visual system. However, little is known about the capacity for patterned spontaneous activity to drive the maturation of receptive fields before visual experience. Retinal waves provide instructive retinotopic information for the anatomical organization of the visual thalamus. To determine whether retinal waves also drive the maturation of functional responses, we increased the frequency of retinal waves pharmacologically in the ferret (Mustela putorius furo) during a period of retinogeniculate development before eye opening. The development of geniculate receptive fields after receiving these increased neural activities was measured using single-unit electrophysiology. We found that increased retinal waves accelerate the developmental reduction of geniculate receptive field sizes. This reduction is due to a decrease in receptive field center size rather than an increase in inhibitory surround strength. This work reveals an instructive role for patterned spontaneous activity in guiding the functional development of neural circuits. SIGNIFICANCE STATEMENT Patterned spontaneous neural activity that occurs during development is known to be necessary for the proper formation of neural circuits. However, it is unknown whether the spontaneous activity alone is sufficient to drive the maturation of the functional properties of neurons. Our work demonstrates for the first time an acceleration in the maturation of neural function as a consequence of driving patterned spontaneous activity during development. This work has implications for our understanding of how neural circuits can be modified actively to improve function prematurely or to recover from injury with guided interventions of patterned neural activity. PMID:26511250

  8. Decreasing excessive media usage while increasing physical activity: a single-subject research study.

    PubMed

    Larwin, Karen H; Larwin, David A

    2008-11-01

    The Kaiser Family Foundation released a report entitled Kids and Media Use in the United States that concluded that children's use of media--including television, computers, Internet, video games, and phones--may be one of the primary contributor's to the poor fitness and obesity of many of today's adolescents. The present study examines the potential of increasing physical activity and decreasing media usage in a 14-year-old adolescent female by making time spent on the Internet and/or cell phone contingent on physical activity. Results of this investigation indicate that requiring the participant to earn her media-usage time did correspond with an increase in physical activity and a decrease in media-usage time relative to baseline measures. Five weeks after cessation of the intervention, the participant's new level of physical activity was still being maintained. One year after the study, the participant's level of physical activity continued to increase. PMID:18544746

  9. Increased writing activity in neurological conditions: a review and clinical study.

    PubMed Central

    van Vugt, P; Paquier, P; Kees, L; Cras, P

    1996-01-01

    Increased writing activity in a 70 year old, right handed man presenting with a history of alcohol misuse and maturity onset diabetes is reported. Brain CT disclosed corticosubcortical atrophy and 99mTc-HMPAO SPECT disclosed severe bilateral frontal hypoperfusion more prominent on the right. The patient's neuropsychological symptomatology consisted of severe (verbal) aspontaneity, intermittent utilisation behaviour, and pronounced increased writing activity, which mainly consisted of a perseverative, micrographic written reproduction of visually or verbally perceived language fragments. Several neurological causes of increased writing activity and the equivocal terminology met in the medical literature are reviewed. A distinction between hypergraphia and automatic writing behaviour is proposed. It is concluded that our patient's increased writing activity may be characterised as automatic writing behaviour. Images PMID:8937347

  10. Bacterial Manipulation of NK Cell Regulatory Activity Increases Susceptibility to Listeria monocytogenes Infection

    PubMed Central

    Guthrie, Brandon S.; Schmidt, Rebecca L.; Jamieson, Amanda; Merkel, Patricia; Knight, Vijaya; Cole, Caroline M.; Raulet, David H.; Lenz, Laurel L.

    2016-01-01

    Natural killer (NK) cells produce interferon (IFN)-γ and thus have been suggested to promote type I immunity during bacterial infections. Yet, Listeria monocytogenes (Lm) and some other pathogens encode proteins that cause increased NK cell activation. Here, we show that stimulation of NK cell activation increases susceptibility during Lm infection despite and independent from robust NK cell production of IFNγ. The increased susceptibility correlated with IL-10 production by responding NK cells. NK cells produced IL-10 as their IFNγ production waned and the Lm virulence protein p60 promoted induction of IL-10 production by mouse and human NK cells. NK cells consequently exerted regulatory effects to suppress accumulation and activation of inflammatory myeloid cells. Our results reveal new dimensions of the role played by NK cells during Lm infection and demonstrate the ability of this bacterial pathogen to exploit the induction of regulatory NK cell activity to increase host susceptibility. PMID:27295349

  11. Increasing Spontaneous Retinal Activity before Eye Opening Accelerates the Development of Geniculate Receptive Fields.

    PubMed

    Davis, Zachary W; Chapman, Barbara; Cheng, Hwai-Jong

    2015-10-28

    Visually evoked activity is necessary for the normal development of the visual system. However, little is known about the capacity for patterned spontaneous activity to drive the maturation of receptive fields before visual experience. Retinal waves provide instructive retinotopic information for the anatomical organization of the visual thalamus. To determine whether retinal waves also drive the maturation of functional responses, we increased the frequency of retinal waves pharmacologically in the ferret (Mustela putorius furo) during a period of retinogeniculate development before eye opening. The development of geniculate receptive fields after receiving these increased neural activities was measured using single-unit electrophysiology. We found that increased retinal waves accelerate the developmental reduction of geniculate receptive field sizes. This reduction is due to a decrease in receptive field center size rather than an increase in inhibitory surround strength. This work reveals an instructive role for patterned spontaneous activity in guiding the functional development of neural circuits. PMID:26511250

  12. Bacterial Manipulation of NK Cell Regulatory Activity Increases Susceptibility to Listeria monocytogenes Infection.

    PubMed

    Clark, Sarah E; Filak, Holly C; Guthrie, Brandon S; Schmidt, Rebecca L; Jamieson, Amanda; Merkel, Patricia; Knight, Vijaya; Cole, Caroline M; Raulet, David H; Lenz, Laurel L

    2016-06-01

    Natural killer (NK) cells produce interferon (IFN)-γ and thus have been suggested to promote type I immunity during bacterial infections. Yet, Listeria monocytogenes (Lm) and some other pathogens encode proteins that cause increased NK cell activation. Here, we show that stimulation of NK cell activation increases susceptibility during Lm infection despite and independent from robust NK cell production of IFNγ. The increased susceptibility correlated with IL-10 production by responding NK cells. NK cells produced IL-10 as their IFNγ production waned and the Lm virulence protein p60 promoted induction of IL-10 production by mouse and human NK cells. NK cells consequently exerted regulatory effects to suppress accumulation and activation of inflammatory myeloid cells. Our results reveal new dimensions of the role played by NK cells during Lm infection and demonstrate the ability of this bacterial pathogen to exploit the induction of regulatory NK cell activity to increase host susceptibility. PMID:27295349

  13. Energy expended playing video console games: an opportunity to increase children's physical activity?

    PubMed

    Maddison, Ralph; Mhurchu, Cliona Ni; Jull, Andrew; Jiang, Yannan; Prapavessis, Harry; Rodgers, Anthony

    2007-08-01

    This study sought to quantify the energy expenditure and physical activity associated with playing the "new generation" active and nonactive console-based video games in 21 children ages 10-14 years. Energy expenditure (kcal) derived from oxygen consumption (VO2) was continuously assessed while children played nonactive and active console video games. Physical activity was assessed continuously using the Actigraph accelerometer. Significant (p < .001) increases from baseline were found for energy expenditure (129-400%), heart rate (43-84%), and activity counts (122-1288 versus 0-23) when playing the active console video games. Playing active console video games over short periods of time is similar in intensity to light to moderate traditional physical activities such as walking, skipping, and jogging. PMID:18019591

  14. Physical activity compensates for increased mortality risk among older people with poor muscle strength.

    PubMed

    Portegijs, E; Rantanen, T; Sipilä, S; Laukkanen, P; Heikkinen, E

    2007-10-01

    The aim of the study was to determine whether habitual physical activity can compensate for the increased mortality risk among older people with poor muscle strength. Mortality was followed up for 10 years after laboratory examination in 558 community dwelling 75- and 80-year-old men and women. Maximal isometric strength of five muscle groups was measured and tertile cut-off points were used to categorize participants. Participants, who reported moderate physical activity for at least 4 h a week, were categorized as physically active and the others as sedentary. High muscle strength and physical activity both protected from mortality, but their effect was not additive. Within each muscle strength tertile, physically active people had a lower mortality risk than sedentary people, the effect being most pronounced among those with lower strength in all muscle groups. A high level of physical activity may thus compensate for the increased mortality associated with low muscle strength. PMID:17166169

  15. Playground designs to increase physical activity levels during school recess: a systematic review.

    PubMed

    Escalante, Yolanda; García-Hermoso, Antonio; Backx, Karianne; Saavedra, Jose M

    2014-04-01

    School recess provides a major opportunity to increase children's physical activity levels. Various studies have described strategies to increase levels of physical activity. The purpose of this systematic review is therefore to examine the interventions proposed as forms of increasing children's physical activity levels during recess. A systematic search of seven databases was made from the July 1 to July 5, 2012, leading to a final set of eight studies (a total of 2,383 subjects-599 "preschoolers" and 1,784 "schoolchildren") meeting the inclusion criteria. These studies were classified according to the intervention used: playground markings, game equipment, playground markings plus physical structures, and playground markings plus game equipment. The results of these studies indicate that the strategies analyzed do have the potential to increase physical activity levels during recess. The cumulative evidence was (a) that interventions based on playground markings, game equipment, or a combination of the two, do not seem to increase the physical activity of preschoolers and schoolchildren during recess and (ii) that interventions based on playground markings plus physical structures do increase the physical activity of schoolchildren during recess in the short to medium term. PMID:23836828

  16. Physical Activity and Executive Control: Implications for Increased Cognitive Health during Older Adulthood

    ERIC Educational Resources Information Center

    Hillman, Charles H.; Belopolsky, Artem V.; Snook, Erin M.; Kramer, Arthur F.; McAuley, Edward

    2004-01-01

    Electrocortical and behavioral responses of low, moderate, and high physically active older adults where compared with a younger control group on neutral and incompatible conditions of a flankers task. Compared to younger adults, high and moderate active older adults exhibited increased event-related potentials component P3 amplitude for the…

  17. Newspaper Content Analysis in Evaluation of a Community-Based Participatory Project to Increase Physical Activity

    ERIC Educational Resources Information Center

    Granner, Michelle L.; Sharpe, Patricia A.; Burroughs, Ericka L.; Fields, Regina; Hallenbeck, Joyce

    2010-01-01

    This study conducted a newspaper content analysis as part of an evaluation of a community-based participatory research project focused on increasing physical activity through policy and environmental changes, which included activities related to media advocacy and media-based community education. Daily papers (May 2003 to December 2005) from both…

  18. 26 CFR 1.280C-4 - Credit for increasing research activities.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 3 2010-04-01 2010-04-01 false Credit for increasing research activities. 1... research activities. (a) In general. The election under section 280C(c)(3) to have the provisions of...) determined by the method provided in section 280C(c)(3)(B) on an original return for the taxable year,...

  19. Focused Campaign Increases Activity among Participants in "Nature's Notebook," a Citizen Science Project

    ERIC Educational Resources Information Center

    Crimmins, Theresa M.; Weltzin, Jake F.; Rosemartin, Alyssa H.; Surina, Echo M.; Marsh, Lee; Denny, Ellen G.

    2014-01-01

    Science projects, which engage non-professional scientists in one or more stages of scientific research, have been gaining popularity; yet maintaining participants' activity level over time remains a challenge. The objective of this study was to evaluate the potential for a short-term, focused campaign to increase participant activity in a…

  20. Increasing Student Physical Activity during the School Day: Opportunities for the Physical Educator

    ERIC Educational Resources Information Center

    Brewer, Joan D.; Luebbers, Paul E.; Shane, Shawna D.

    2009-01-01

    America is facing an obesity epidemic--one that is difficult to ignore. In order to combat the nation's obesity crisis, it is imperative that schools find ways to increase the physical activity levels of students during the school day, as well as encourage additional activity outside of school. By teaching youth to incorporate physical activity…

  1. Effects of increasing physical activity on foot structure and ankle muscle strength in adults with obesity

    PubMed Central

    Zhao, Xiaoguang; Tsujimoto, Takehiko; Kim, Bokun; Katayama, Yasutomi; Wakaba, Kyousuke; Wang, Zhennan; Tanaka, Kiyoji

    2016-01-01

    [Purpose] The purpose of this study was to examine the effects of increasing physical activity on foot structure and ankle muscle strength in adults with obesity and to verify whether the rate of change in foot structure is related to that in ankle muscle strength. [Subjects and Methods] Twenty-seven adults with obesity completed a 12-week program in which the intensity of physical activity performed was gradually increased. Physical activity was monitored using a three-axis accelerometer. Foot structure was assessed using a three-dimensional foot scanner, while ankle muscle strength was measured using a dynamometry. [Results] With the increasing physical activity, the participants’ feet became thinner (the rearfoot width, instep height, and girth decreased) and the arch became higher (the arch height index increased) and stiffer (the arch stiffness index increased); the ankle muscle strength also increased after the intervention. Additionally, the changes in the arch height index and arch stiffness index were not associated with changes in ankle muscle strength. [Conclusion] Increasing physical activity may be one possible approach to improve foot structure and function in individuals with obesity.

  2. Activation of intestinal peroxisome proliferator-activated receptor-α increases high-density lipoprotein production

    PubMed Central

    Colin, Sophie; Briand, Olivier; Touche, Véronique; Wouters, Kristiaan; Baron, Morgane; Pattou, François; Hanf, Rémy; Tailleux, Anne; Chinetti, Giulia; Staels, Bart; Lestavel, Sophie

    2013-01-01

    Aims Peroxisome Proliferator-Activated Receptor (PPAR) α is a transcription factor controlling lipid metabolism in liver, heart, muscle and macrophages. PPARα-activation increases plasma HDL-cholesterol and exerts hypotriglyceridemic actions via the liver. However, the intestine expresses PPARα, produces HDL and chylomicrons and is exposed to diet-derived PPARα ligands. Therefore, we examined the effects of PPARα-activation on intestinal lipid and lipoprotein metabolism. Methods and Results The impact of PPARα-activation was evaluated in term of HDL-related gene expression in mice, ex-vivo in human jejunal biopsies and in Caco-2/TC7 cells. ApoAI/HDL secretion, cholesterol esterification and trafficking were also studied in-vitro. In parallel to improving plasma lipid profiles and increasing liver and intestinal expression of fatty-acid-oxidation genes, treatment with the dual PPARα/δ-ligand GFT505 resulted in a more pronounced increase of plasma HDL compared to fenofibrate in mice. GFT505, but not fenofibrate, increased the expression of HDL-production genes such as apolipoprotein-AI and ATP-Binding-Cassette-A1 transporter in murine intestines. A similar increase was observed upon PPARα-activation of human biopsies and Caco-2/TC7 cells. Additionally, HDL secretion by Caco-2/TC7 cells increased. Moreover, PPARα-activation decreased the cholesterol-esterification capacity of Caco-2/TC7 cells, modified cholesterol trafficking and reduced apolipoprotein-B secretion. Conclusions PPARα-activation reduces cholesterol esterification, suppresses chylomicron- and increases HDL-secretion by enterocytes. These results identify the intestine as a target organ of PPARα-ligands with entero-hepatic tropism to reduce atherogenic dyslipidemia. PMID:22843443

  3. Increased Mucosal CD4+ T Cell Activation in Rhesus Macaques following Vaccination with an Adenoviral Vector

    PubMed Central

    Bukh, Irene; Calcedo, Roberto; Roy, Soumitra; Carnathan, Diane G.; Grant, Rebecca; Qin, Qiuyue; Boyd, Surina; Ratcliffe, Sarah J.; Veeder, Christin L.; Bellamy, Scarlett L.; Betts, Michael R.

    2014-01-01

    ABSTRACT The possibility that vaccination with adenovirus (AdV) vectors increased mucosal T cell activation remains a central hypothesis to explain the potential enhancement of HIV acquisition within the Step trial. Modeling this within rhesus macaques is complicated because human adenoviruses, including human adenovirus type 5 (HAdV-5), are not endogenous to macaques. Here, we tested whether vaccination with a rhesus macaque-derived adenoviral vector (simian adenovirus 7 [SAdV-7]) enhances mucosal T cell activation within rhesus macaques. Following intramuscular SAdV-7 vaccination, we observed a pronounced increase in SAdV-7-specific CD4+ T cell responses in peripheral blood and, more dramatically, in rectal mucosa tissue. Vaccination also induced a significant increase in the frequency of activated memory CD4+ T cells in SAdV-7- and HAdV-5-vaccinated animals in the rectal mucosa but not in peripheral blood. These fluctuations within the rectal mucosa were also associated with a pronounced decrease in the relative frequency of naive resting CD4+ T cells. Together, these results indicate that peripheral vaccination with an AdV vector can increase the activation of mucosal CD4+ T cells, potentially providing an experimental model to further evaluate the role of host-vector interactions in increased HIV acquisition after AdV vector vaccination. IMPORTANCE The possibility that vaccination with a human adenovirus 5 vector increased mucosal T cell activation remains a central hypothesis to explain the potential enhancement of human immunodeficiency virus (HIV) acquisition within the Step trial. In this study, we tested whether vaccination with a rhesus macaque-derived adenoviral vector in rhesus macaques enhances mucosal CD4+ T cell activation, the main cell target of simian immunodeficiency virus (SIV)/HIV. The results showed that vaccination with an adenoviral vector indeed increases activation of mucosal CD4+ T cells and potentially increases susceptibility to SIV

  4. Increasing western US forest wildfire activity: sensitivity to changes in the timing of spring.

    PubMed

    Westerling, Anthony LeRoy

    2016-06-01

    Prior work shows western US forest wildfire activity increased abruptly in the mid-1980s. Large forest wildfires and areas burned in them have continued to increase over recent decades, with most of the increase in lightning-ignited fires. Northern US Rockies forests dominated early increases in wildfire activity, and still contributed 50% of the increase in large fires over the last decade. However, the percentage growth in wildfire activity in Pacific northwestern and southwestern US forests has rapidly increased over the last two decades. Wildfire numbers and burned area are also increasing in non-forest vegetation types. Wildfire activity appears strongly associated with warming and earlier spring snowmelt. Analysis of the drivers of forest wildfire sensitivity to changes in the timing of spring demonstrates that forests at elevations where the historical mean snow-free season ranged between two and four months, with relatively high cumulative warm-season actual evapotranspiration, have been most affected. Increases in large wildfires associated with earlier spring snowmelt scale exponentially with changes in moisture deficit, and moisture deficit changes can explain most of the spatial variability in forest wildfire regime response to the timing of spring.This article is part of the themed issue 'The interaction of fire and mankind'. PMID:27216510

  5. Increasing Physical Activity in Preschool: A Pilot Study to Evaluate Animal Trackers

    ERIC Educational Resources Information Center

    Williams, Christine L.; Carter, Betty Jean; Kibbe, Debra L.; Dennison, David

    2009-01-01

    Objective: This report describes a pilot study to evaluate Animal Trackers (AT), a preschool program designed to (1) increase structured physical activity (PA) during the preschool day; (2) increase practice of gross motor skills; (3) provide teachers with an easy-to-use PA program regardless of teacher experience; and (4) implement a teacher…

  6. USING THE Internet TO INCREASE Physical Activity IN A FAITH COMMUNITY.

    PubMed

    Washington, Enrika; Weed, Latricia Diane; Vardaman, Shellye A

    2015-01-01

    Physical inactivity is the biggest public health problem of the 21st Century. Additionally, minority populations have higher rates of obesity and obesity-related illnesses, supporting the need to develop culturally-appropriate physical activity interventions for these populations. For African Americans (AAs), churches promote spiritual, mental, and physical well-being. The Internet offers an innovative medium to produce health behavior change and may be ideal to use with AAs in a church setting. A simple, no-cost, 8-week, Internet-delivered intervention to increase physical activity was piloted in an AA church. Level of activity increased, whereas time spent sitting decreased. PMID:26211303

  7. Successful Face Recognition is Associated with Increased Prefrontal Cortex Activation in Autism Spectrum Disorder

    PubMed Central

    Herrington, John D.; Riley, Meghan E.; Grupe, Daniel W.; Schultz, Robert T.

    2014-01-01

    This study examines whether deficits in visual information processing in ASD can be offset by the recruitment of brain structures involved in selective attention. During functional MRI, 12 children with ASD and 19 control participants completed a selective attention one-back task in which images of faces and houses were superimposed. When attending to faces, the ASD group showed increased activation relative to control participants within multiple prefrontal cortex areas, including dorsolateral prefrontal cortex (DLPFC). DLPFC activation in ASD was associated with increased response times for faces. These data suggest that prefrontal cortex activation may represent a compensatory mechanism for diminished visual information processing abilities. PMID:25234479

  8. Transgenic Expression of Cyclin-Dependent Kinase 4 Results in Epidermal Hyperplasia, Hypertrophy, and Severe Dermal Fibrosis

    PubMed Central

    Miliani de Marval, Paula L.; Gimenez-Conti, Irma B.; LaCava, Margaret; Martinez, Luis A.; Conti, Claudio J.; Rodriguez-Puebla, Marcelo L.

    2001-01-01

    In a previous report we have described the effects of expression of D-type cyclins in epithelial tissues of transgenic mice. To study the involvement of the D-type cyclin partner cyclin-dependent kinase 4 (CDK4) in epithelial growth and differentiation, transgenic mice were generated carrying the CDK4 gene under the control of a keratin 5 promoter. As expected, transgenic mice showed expression of CDK4 in the epidermal basal-cell layer. Epidermal proliferation increased dramatically and basal cell hyperplasia and hypertrophy were observed. The hyperproliferative phenotype of these transgenic mice was independent of D-type cyclin expression because no overexpression of these proteins was detected. CDK4 and CDK2 kinase activities increased in transgenic animals and were associated with elevated binding of p27Kip1 to CDK4. Expression of CDK4 in the epidermis results in an increased spinous layer compared with normal epidermis, and a mild hyperkeratosis in the cornified layer. In addition to epidermal changes, severe dermal fibrosis was observed and part of the subcutaneous adipose tissue was replaced by connective tissue. Also, abnormal expression of keratin 6 associated with the hyperproliferative phenotype was observed in transgenic epidermis. This model provides in vivo evidence for the role of CDK4 as a mediator of proliferation in epithelial cells independent of D-type cyclin expression. PMID:11438484

  9. p53 increases caspase-6 expression and activation in muscle tissue expressing mutant huntingtin.

    PubMed

    Ehrnhoefer, Dagmar E; Skotte, Niels H; Ladha, Safia; Nguyen, Yen T N; Qiu, Xiaofan; Deng, Yu; Huynh, Khuong T; Engemann, Sabine; Nielsen, Signe M; Becanovic, Kristina; Leavitt, Blair R; Hasholt, Lis; Hayden, Michael R

    2014-02-01

    Activation of caspase-6 in the striatum of both presymptomatic and affected persons with Huntington's disease (HD) is an early event in the disease pathogenesis. However, little is known about the role of caspase-6 outside the central nervous system (CNS) and whether caspase activation might play a role in the peripheral phenotypes, such as muscle wasting observed in HD. We assessed skeletal muscle tissue from HD patients and well-characterized mouse models of HD. Cleavage of the caspase-6 specific substrate lamin A is significantly increased in skeletal muscle obtained from HD patients as well as in muscle tissues from two different HD mouse models. p53, a transcriptional activator of caspase-6, is upregulated in neuronal cells and tissues expressing mutant huntingtin. Activation of p53 leads to a dramatic increase in levels of caspase-6 mRNA, caspase-6 activity and cleavage of lamin A. Using mouse embryonic fibroblasts (MEFs) from YAC128 mice, we show that this increase in caspase-6 activity can be mitigated by pifithrin-α (pifα), an inhibitor of p53 transcriptional activity, but not through the inhibition of p53's mitochondrial pro-apoptotic function. Remarkably, the p53-mediated increase in caspase-6 expression and activation is exacerbated in cells and tissues of both neuronal and peripheral origin expressing mutant huntingtin (Htt). These findings suggest that the presence of the mutant Htt protein enhances p53 activity and lowers the apoptotic threshold, which activates caspase-6. Furthermore, these results suggest that this pathway is activated both within and outside the CNS in HD and may contribute to both loss of CNS neurons and muscle atrophy. PMID:24070868

  10. Increased physical activity decreases hepatic free fatty acid uptake: a study in human monozygotic twins.

    PubMed

    Hannukainen, Jarna C; Nuutila, Pirjo; Borra, Ronald; Ronald, Borra; Kaprio, Jaakko; Kujala, Urho M; Janatuinen, Tuula; Heinonen, Olli J; Kapanen, Jukka; Viljanen, Tapio; Haaparanta, Merja; Rönnemaa, Tapani; Parkkola, Riitta; Knuuti, Juhani; Kalliokoski, Kari K

    2007-01-01

    Exercise is considered to be beneficial for free fatty acid (FFA) metabolism, although reports of the effects of increased physical activity on FFA uptake and oxidation in different tissues in vivo in humans have been inconsistent. To investigate the heredity-independent effects of physical activity and fitness on FFA uptake in skeletal muscle, the myocardium, and liver we used positron emission tomography (PET) in nine healthy young male monozygotic twin pairs discordant for physical activity and fitness. The cotwins with higher physical activity constituting the more active group had a similar body mass index but less body fat and 18 +/- 10% higher (P < 0.001) compared to the less active brothers with lower physical activity. Low-intensity knee-extension exercise increased skeletal muscle FFA and oxygen uptake six to 10 times compared to resting values but no differences were observed between the groups at rest or during exercise. At rest the more active group had lower hepatic FFA uptake compared to the less active group (5.5 +/- 4.3 versus 9.0 +/- 6.1 micromol (100 ml)(-1) min(-1), P = 0.04). Hepatic FFA uptake associated significantly with body fat percentage (P = 0.05). Myocardial FFA uptake was similar between the groups. In conclusion, in the absence of the confounding effects of genetic factors, moderately increased physical activity and aerobic fitness decrease body adiposity even in normal-weighted healthy young adult men. Further, increased physical activity together with decreased intra-abdominal adiposity seems to decrease hepatic FFA uptake but has no effects on skeletal muscle or myocardial FFA uptake. PMID:17053033

  11. Salivary Acetylcholinesterase Activity Is Increased in Parkinson's Disease: A Potential Marker of Parasympathetic Dysfunction

    PubMed Central

    Fedorova, Tatyana; Knudsen, Cindy Soendersoe; Mouridsen, Kim; Nexo, Ebba; Borghammer, Per

    2015-01-01

    Introduction. Decreased salivary flow and xerostomia are frequent findings in Parkinson's disease (PD), possibly caused by alterations in the parasympathetic tonus. Here we explore salivary acetylcholinesterase (AChE) activity as a potential biomarker in PD. Methods. We measured salivary flow, AChE activity, and total protein concentration in 30 PD patients and 49 healthy controls. We also performed exploratory correlation analyses with disease duration, motor symptom severity, autonomic complaints, and other nonmotor symptoms. Results. PD patients displayed significantly decreased salivary flow rate, significantly increased salivary AChE activity, and total protein concentration. Importantly, the AChE activity/total protein ratio was significantly increased in PD patients, suggesting that increased AChE activity cannot be explained solely by upconcentration of saliva. The Unified PD Rating Scale (UPDRS) score displayed significant correlation with total salivary protein (P = 0.002) and near-significant correlation with salivary flow (P = 0.07). Color vision test scores were also significantly correlated with AChE activity (P = 0.04) and total protein levels (P = 0.002). Conclusion. Salivary AChE activity is increased in PD patients compared to healthy controls. Future studies are needed to elucidate whether this parameter reflects the extent of neuronal damage and parasympathetic denervation in the salivary glands of PD patients. PMID:25767737

  12. A-Ring Dihalogenation Increases the Cellular Activity of Combretastatin-Templated Tetrazoles

    PubMed Central

    2012-01-01

    The combretastatins have been investigated for their antimitotic and antivascular properties, and it is widely postulated that a 3,4,5-trimethoxyaryl A-ring is essential to maintain potent activity. We have synthesized new tetrazole analogues (32–34), demonstrating that 3,5-dihalogenation can consistently increase potency by up to 5-fold when compared to the equivalent trimethoxy compound on human umbilical vein endothelial cells (HUVECs) and a range of cancer cells. Moreover, this increased potency offsets that lost by installing the tetrazole bridge into combretastatin A-4 (1), giving crystalline, soluble compounds that have low nanomolar activity, arrest cells in G2/M phase, and retain microtubule inhibitory activity. Molecular modeling has shown that optimized packing within the binding site resulting in increased Coulombic interaction may be responsible for this improved activity. PMID:24900453

  13. BrO/SO2 ratios at Popocatepetl volcano during increased activity in 2012

    NASA Astrophysics Data System (ADS)

    Fickel, M.; Delgado Granados, H.

    2012-12-01

    Since its reactivation in 1994 after many decades of inactivity, Popocatepetl volcano has been showing long periods of quiescent degassing and some events of intensified activity in connection with dome building and destruction processes. During a period of increased activity of the volcano, which began in April 2012, mobile ultraviolet DOAS measurements and stationary DOAS scans were performed to quantify SO2 fluxes and BrO/SO2 ratios within the volcanic plume. The results of these measurements are presented in the context of the volcanic activity, which consisted of increased emission of gas and ash and Vulcanian type explosions. In general, SO2 emissions were high during the period April-June 2012 and so the BrO emissions, however, the BrO/SO2 ratios did not change strongly before, during and after the increased activity.

  14. Preliminary efficacy of prize-based contingency management to increase activity levels in healthy adults.

    PubMed

    Washington, Wendy Donlin; Banna, Kelly M; Gibson, Amanda L

    2014-01-01

    An estimated 30% of Americans meet the criteria for obesity. Effective, low-cost interventions to increase physical activity are needed to prevent and treat obesity. In this study, 11 healthy adults wore Fitbit accelerometers for 3 weeks. During the initial baseline, subjects earned prize draws for wearing the Fitbit. During intervention, percentile schedules were used to calculate individual prize-draw criteria. The final week was a return to baseline. Four subjects increased step counts as a result of the intervention. A bout analysis of interresponse times revealed that subjects increased overall step counts by increasing daily minutes active and within-bout response rates and decreasing pauses between bouts of activity. Strategies to improve effectiveness are suggested, such as modification of reinforcement probability and amount and identification of the function of periods of inactivity. PMID:24740477

  15. Apocynin increases glutathione synthesis and activates AP-1 in alveolar epithelial cells.

    PubMed

    Lapperre, T S; Jimenez, L A; Antonicelli, F; Drost, E M; Hiemstra, P S; Stolk, J; MacNee, W; Rahman, I

    1999-01-25

    Apocynin (4-hydroxy-3-methoxy-acetophenone) is a potent intracellular inhibitor of superoxide anion production in neutrophils. In this study, we studied the effect of apocynin on the regulation of the antioxidant glutathione (GSH) and activation of the transcription factor AP-I in human alveolar epithelial cells (A549). Apocynin enhanced intracellular GSH by increasing gamma-glutamylcysteine synthetase activity in A549 cells. Apocynin also increased the expression of gamma-GCS heavy subunit mRNA. This was associated with increased AP-1 DNA binding as measured by the electrophoretic mobility shift assay. These data indicate that apocynin displays antioxidant properties, in part, by increasing glutathione synthesis through activation of AP-1. PMID:9989612

  16. Calpain activity and expression are increased in splenic inflammatory cells associated with experimental allergic encephalomyelitis.

    PubMed

    Shields, D C; Schaecher, K E; Goust, J M; Banik, N L

    1999-09-01

    Since calcium-activated neutral proteinase (calpain) activity and expression are significantly increased in activated glial/inflammatory cells in the central nervous system of animals with autoimmune demyelinating diseases, this enzyme may also play a role in peripheral organ systems in these diseases. In this study, the activity and expression of calpain and the endogenous inhibitor, calpastatin, were evaluated at transcriptional and translational levels in spleens of Lewis rats with acute experimental allergic encephalomyelitis (EAE) prior to the onset of clinical symptoms. Calpain activity and translational expression were increased by 475.5% and 44.3% respectively, on day 4 post-induction in adjuvant controls and animals with EAE. These levels remained elevated compared to normal controls on days 8 and 12. Calpastatin translational expression was similarly increased at these time points although transcriptional expression was not significantly altered at any time following induction of EAE. Likewise, transcriptional expression of mu-calpain was unchanged following induction, while small increases in m-calpain transcriptional expression were observed on days 2 and 8. Most calpain expression was observed in activated splenic macrophages at day 8 post-induction even though activated T cells were also calpain positive. In spinal cords of animals with EAE, calpain expression was significantly increased in rats with severe disease compared to those exhibiting only mild symptoms at day 12 post-induction. Thus, prior to symptomatic EAE, increased calpain activity and expression in peripheral lymphoid organs may play an important role in T cell migration and subsequent disease progression. PMID:10496171

  17. Increase of rutin antioxidant activity by generating Maillard reaction products with lysine.

    PubMed

    Zhang, Ru; Zhang, Bian-Ling; He, Ting; Yi, Ting; Yang, Ji-Ping; He, Bin

    2016-06-01

    Rutin exists in medicinal herbs, fruits, vegetables, and a number of plant-derived sources. Dietary sources containing rutin are considered beneficial because of their potential protective roles in multiple diseases related to oxidative stresses. In the present study, the change and antioxidation activity of rutin in Maillard reaction with lysine through a heating process were investigated. There is release of glucose and rhamnose that interact with lysine to give Maillard reaction products (MRPs), while rutin is converted to less-polar quercetin and a small quantity of isoquercitrin. Because of their high cell-membrane permeability, the rutin-lysine MRPs increase the free radical-scavenging activity in HepG2 cells, showing cellular antioxidant activity against Cu(2+)-induced oxidative stress higher than that of rutin. Furthermore, the MRPs significantly increased the Cu/Zn SOD (superoxide dismutase) activity and Cu/Zn SOD gene expression of HepG2 cells, consequently enhancing antioxidation activity. PMID:27106712

  18. Nandrolone reduces activation of Notch signaling in denervated muscle associated with increased Numb expression.

    PubMed

    Liu, Xin-Hua; Yao, Shen; Qiao, Rui-Fang; Levine, Alice C; Kirschenbaum, Alexander; Pan, Jiangping; Wu, Yong; Qin, Weiping; Bauman, William A; Cardozo, Christopher P

    2011-10-14

    Nandrolone, an anabolic steroid, slows denervation-atrophy in rat muscle. The molecular mechanisms responsible for this effect are not well understood. Androgens and anabolic steroids activate Notch signaling in animal models of aging and thereby mitigate sarcopenia. To explore the molecular mechanisms by which nandrolone prevents denervation-atrophy, we investigated the effects of nandrolone on Notch signaling in denervated rat gastrocnemius muscle. Denervation significantly increased Notch activity reflected by elevated levels of nuclear Notch intracellular domain (NICD) and expression of Hey1 (a Notch target gene). Activation was greatest at 7 and 35 days after denervation but remained present at 56 days after denervation. Activation of Notch in denervated muscle was prevented by nandrolone associated with upregulated expression of Numb mRNA and protein. These data demonstrate that denervation activates Notch signaling, and that nandrolone abrogates this response associated with increased expression of Numb, suggesting a potential mechanism by which nandrolone reduces denervation-atrophy. PMID:21945932

  19. Indirect aluminum toxicity to the green alga Scenedesmus through increased cupric ion activity

    SciTech Connect

    Rueter, J.G. Jr.; O'Reilly, K.T.; Petersen, R.R.

    1987-05-01

    Additions of aluminum and copper to chemically defined media resulted in inhibition of growth of Scenedesmus and of alkaline phosphatase activity. The alkaline phosphatase activity was assayed both on commercially available purified enzyme from bacteria and on the enzyme present in whole Scenedesmus cells. The effect of metal additions was compared to the total aluminum added and to the computed free ion activities for both copper and aluminum. In all three systems (algal growth, purified enzyme, and algal enzyme) the observed toxicity with increased total aluminum was mostly due to an increase in cupric ion activity. The algal growth response was affected for the range of cupric ion activities from 10/sup -6/ to 10/sup -12/. The toxic dose response of aluminum was largely due to indirect competitive effects of Al in the medium that displaced copper from the chelator. 33 references, 4 figures.

  20. Plasma cathepsin D isoforms and their active metabolites increase after myocardial infarction and contribute to plasma renin activity.

    PubMed

    Naseem, R Haris; Hedegard, Wade; Henry, Timothy D; Lessard, Jennifer; Sutter, Kathryn; Katz, Stephen A

    2005-03-01

    Plasma renin activity (PRA) is often found to increase after myocardial infarction (MI). Elevated PRA may contribute to increased myocardial angiotensin II that is responsible for maladaptive remodeling of the myocardium after MI. We hypothesized that MI would also result in cardiac release of cathepsin D, a ubiquitous lysosomal enzyme with high renin sequence homology. Cathepsin D release from damaged myocardial tissue could contribute to angiotensin formation by acting as an enzymatic alternate to renin. We assessed circulating renin and cathepsin D from both control and MI patient plasma (7-20 hours after MI) using shallow gradient focusing that allowed for independent measurement of both enzymes. Cathepsin D was increased significantly in the plasma after MI (P < 0.001). Furthermore, circulating active cathepsin D metabolites were also significantly elevated after MI (P < 0.04), and contained the majority of cathepsin D activity in plasma. Spiking control plasma with cathepsin D resulted in a variable but significant (P = 0.005) increase in PRA using a clinical assay. We conclude that 7-20 hours after MI, plasma cathepsin D is significantly elevated and most of the active enzymatic activity is circulating as plasma metabolites. Circulating cathepsin D can falsely increase clinical PRA determinations, and may also provide an alternative angiotensin formation pathway after MI. PMID:15739123

  1. Vagus Nerve Stimulation Increases Energy Expenditure: Relation to Brown Adipose Tissue Activity

    PubMed Central

    Vijgen, Guy H. E. J.; Bouvy, Nicole D.; Leenen, Loes; Rijkers, Kim; Cornips, Erwin; Majoie, Marian; Brans, Boudewijn; van Marken Lichtenbelt, Wouter D.

    2013-01-01

    Background Human brown adipose tissue (BAT) activity is inversely related to obesity and positively related to energy expenditure. BAT is highly innervated and it is suggested the vagus nerve mediates peripheral signals to the central nervous system, there connecting to sympathetic nerves that innervate BAT. Vagus nerve stimulation (VNS) is used for refractory epilepsy, but is also reported to generate weight loss. We hypothesize VNS increases energy expenditure by activating BAT. Methods and Findings Fifteen patients with stable VNS therapy (age: 45±10yrs; body mass index; 25.2±3.5 kg/m2) were included between January 2011 and June 2012. Ten subjects were measured twice, once with active and once with inactivated VNS. Five other subjects were measured twice, once with active VNS at room temperature and once with active VNS under cold exposure in order to determine maximal cold-induced BAT activity. BAT activity was assessed by 18-Fluoro-Deoxy-Glucose-Positron-Emission-Tomography-and-Computed-Tomography. Basal metabolic rate (BMR) was significantly higher when VNS was turned on (mean change; +2.2%). Mean BAT activity was not significantly different between active VNS and inactive VNS (BAT SUVMean; 0.55±0.25 versus 0.67±0.46, P = 0.619). However, the change in energy expenditure upon VNS intervention (On-Off) was significantly correlated to the change in BAT activity (r = 0.935, P<0.001). Conclusions VNS significantly increases energy expenditure. The observed change in energy expenditure was significantly related to the change in BAT activity. This suggests a role for BAT in the VNS increase in energy expenditure. Chronic VNS may have a beneficial effect on the human energy balance that has potential application for weight management therapy. Trial Registration The study was registered in the Clinical Trial Register under the ClinicalTrials.gov Identifier NCT01491282. PMID:24194874

  2. Neuromedin U in the paraventricular and arcuate hypothalamic nuclei increases non-exercise activity thermogenesis.

    PubMed

    Novak, C M; Zhang, M; Levine, J A

    2006-08-01

    Brain neuromedin U (NMU) has been associated with the regulation of both energy intake and expenditure. We hypothesized that NMU induces changes in spontaneous physical activity and nonexercise activity thermogenesis (NEAT) through its actions on hypothalamic nuclei. We applied increasing doses of NMU directly to the paraventricular (PVN) and arcuate hypothalamic nuclei using chronic unilateral guide cannulae. In both nuclei, NMU significantly and dose-dependently increased physical activity and NEAT. Moreover, NMU increased physical activity and NEAT during the first hour of the dark phase, indicating that the reduction of sleep is unlikely to account for the increased physical activity seen with NMU treatment. As a positive control, we demonstrated that paraventricular NMU also significantly decreased food intake, as well as body weight. These data demonstrate that NMU is positively associated with NEAT through its actions in the PVN and arcuate nucleus. In co-ordination with its suppressive effects on feeding, the NEAT-activating effects of NMU make it a potential candidate in the combat of obesity. PMID:16867180

  3. Increased cell proliferation and neural activity by physostigmine in the telencephalon of adult zebrafish.

    PubMed

    Lee, Yunkyoung; Lee, Bongkyu; Jeong, Sumin; Park, Ji-Won; Han, Inn-Oc; Lee, Chang-Joong

    2016-08-26

    Physostigmine, an acetylcholinesterase inhibitor, is known to affect the brain function in various aspects. This study was conducted to test whether physostigmine affects cell proliferation in the telencephalon of zebrafish. BrdU-labeled cells was prominently observed in the ventral zone of the ventral telencephalon of zebrafish. The increased number of BrdU- and proliferating cell nuclear antigen-labeled cells were shown in zebrafish treated with 200μM physostigmine, which was inhibited by pretreatment with 200μM scopolamine. iNOS mRNA expression was increased in the brain of zebrafish treated with 200μM physostigmine. Consistently, aminoguanidine, an iNOS inhibitor, attenuated the increase in the number of BrdU-labeled cells by physostigmine treatment. Zebrafish also showed seizure-like locomotor activity characterized by a rapid and abrupt movement during a 30min treatment with 200μM physostigmine. Neural activity in response to an electrical stimulus was increased in the isolated telencephalon of zebrafish continuously perfused with 200μM physostigmine. None of the number of BrdU-labeled cells, neural activity, or locomotor activity was affected by treatment with 20μM physostigmine. These results suggest that 200μM physostigmine increased neural activity and induced cell proliferation via nitric oxide production in zebrafish. PMID:27378362

  4. Oxytocin increases VTA activation to infant and sexual stimuli in nulliparous and postpartum women.

    PubMed

    Gregory, Rebecca; Cheng, Hu; Rupp, Heather A; Sengelaub, Dale R; Heiman, Julia R

    2015-03-01

    After giving birth, women typically experience decreased sexual desire and increased responsiveness to infant stimuli. These postpartum changes may be viewed as a trade-off in reproductive interests, which could be due to alterations in brain activity including areas associated with reward. The goal of this study was to describe the roles of oxytocin and parity on reward area activation in response to reproductive stimuli, specifically infant and sexual images. Because they have been shown to be associated with reward, the ventral tegmental area (VTA) and nucleus accumbens (NAc) were targeted as areas of expected alterations in activity. Oxytocin was chosen as a potential mediator of reproductive trade-offs because of its relationship to both mother-infant interactions, including breastfeeding and bonding, and sexual responses. We predicted that postpartum women would show higher reward area activation to infant stimuli and nulliparous women would show higher activation to sexual stimuli and that oxytocin would increase activation to infant stimuli in nulliparous women. To test this, we measured VTA and NAc activation using fMRI in response to infant photos, sexual photos, and neutral photos in 29 postpartum and 30 nulliparous women. Participants completed the Sexual Inhibition (SIS) and Sexual Excitation (SES) Scales and the Brief Index of Sexual Function for Women (BISF-W), which includes a sexual desire dimension, and received either oxytocin or placebo nasal spray before viewing crying and smiling infant and sexual images in an fMRI scanner. For both groups of women, intranasal oxytocin administration increased VTA activation to both crying infant and sexual images but not to smiling infant images. We found that postpartum women showed lower SES, higher SIS, and lower sexual desire compared to nulliparous women. Across parity groups, SES scores were correlated with VTA activation and subjective arousal ratings to sexual images. In postpartum women, sexual

  5. Oxytocin increases VTA activation to infant and sexual stimuli in nulliparous and postpartum women

    PubMed Central

    Gregory, Rebecca; Cheng, Hu; Rupp, Heather A.; Sengelaub, Dale R.; Heiman, Julia R.

    2015-01-01

    After giving birth, women typically experience decreased sexual desire and increased responsiveness to infant stimuli. These postpartum changes may be viewed as a trade-off in reproductive interests, which could be due to alterations in brain activity including areas associated with reward. The goal of this study was to describe the roles of oxytocin and parity on reward area activation in response to reproductive stimuli, specifically infant and sexual images. Because they have been shown to be associated with reward, the ventral tegmental area (VTA) and nucleus accumbens (NAc) were targeted as areas of expected alterations in activity. Oxytocin was chosen as a potential mediator of reproductive trade-offs because of its relationship to both mother–infant interactions, including breastfeeding and bonding, and sexual responses. We predicted that postpartum women would show higher reward area activation to infant stimuli and nulliparous women would show higher activation to sexual stimuli and that oxytocin would increase activation to infant stimuli in nulliparous women. To test this, we measured VTA and NAc activation using fMRI in response to infant photos, sexual photos, and neutral photos in 29 postpartum and 30 nulliparous women. Participants completed the Sexual Inhibition (SIS) and Sexual Excitation (SES) Scales and the Brief Index of Sexual Function for Women (BISF-W), which includes a sexual desire dimension, and received either oxytocin or placebo nasal spray before viewing crying and smiling infant and sexual images in an fMRI scanner. For both groups of women, intranasal oxytocin administration increased VTA activation to both crying infant and sexual images but not to smiling infant images. We found that postpartum women showed lower SES, higher SIS, and lower sexual desire compared to nulliparous women. Across parity groups, SES scores were correlated with VTA activation and subjective arousal ratings to sexual images. In postpartum women, sexual

  6. Flaking process increases the NF-κB inhibition activity and melanoidin extractability of coffee.

    PubMed

    Chu, Yi-Fang; Hu, Kang; Hatzold, Thomas; Black, Richard M; Chen, Don

    2013-09-01

    Research on the health impacts of coffee has escalated. However, few studies were devoted to understanding the potential impact of mechanical processing on coffee's chemistry and subsequent health implications. Coffee flaking is a commonly used process to improve extractability and aroma characteristics. In this study, we studied the biochemical activity, chemical composition, and microstructure of coffee before and after flaking. We found that flaked coffee extract had 3.3-fold higher activity in inhibiting nuclear factor-kappa B (NF-κB) activation than regular coffee extract. Interestingly, flaking did not significantly alter the amount of coffee phenolics. It increased coffee melanoidin, by 2.1-fold, which likely contributed to the observed higher activity in inhibiting NF-κB activation. Flaking crushed cell walls revealed by microscopy might possibly result in disruption of polysaccharide entanglement and release of high-molecular-weight compounds, such as melanoidins. Consequently, the increased melanoidin content in the brew resulted in the increased inhibition of NF-κB activation. Small molecules, like coffee phenolics, are readily soluble in water during coffee brewing even without flaking, suggesting that flaking has no effect on its extractability. In summary, our investigation revealed that flaking enhanced NF-κB inhibition activity, possibly through the release of melanoidins from crushed cell microstructures. PMID:24804042

  7. Flaking process increases the NF-κB inhibition activity and melanoidin extractability of coffee

    PubMed Central

    Chu, Yi-Fang; Hu, Kang; Hatzold, Thomas; Black, Richard M; Chen, Don

    2013-01-01

    Research on the health impacts of coffee has escalated. However, few studies were devoted to understanding the potential impact of mechanical processing on coffee's chemistry and subsequent health implications. Coffee flaking is a commonly used process to improve extractability and aroma characteristics. In this study, we studied the biochemical activity, chemical composition, and microstructure of coffee before and after flaking. We found that flaked coffee extract had 3.3-fold higher activity in inhibiting nuclear factor-kappa B (NF-κB) activation than regular coffee extract. Interestingly, flaking did not significantly alter the amount of coffee phenolics. It increased coffee melanoidin, by 2.1-fold, which likely contributed to the observed higher activity in inhibiting NF-κB activation. Flaking crushed cell walls revealed by microscopy might possibly result in disruption of polysaccharide entanglement and release of high-molecular-weight compounds, such as melanoidins. Consequently, the increased melanoidin content in the brew resulted in the increased inhibition of NF-κB activation. Small molecules, like coffee phenolics, are readily soluble in water during coffee brewing even without flaking, suggesting that flaking has no effect on its extractability. In summary, our investigation revealed that flaking enhanced NF-κB inhibition activity, possibly through the release of melanoidins from crushed cell microstructures. PMID:24804042

  8. Fenofibrate activates AMPK and increases eNOS phosphorylation in HUVEC

    SciTech Connect

    Murakami, Hisashi; Murakami, Ryuichiro . E-mail: ryuichi@med.nagoya-u.ac.jp; Kambe, Fukushi; Cao, Xia; Takahashi, Ryotaro; Asai, Toru; Hirai, Toshihisa; Numaguchi, Yasushi; Okumura, Kenji; Seo, Hisao; Murohara, Toyoaki

    2006-03-24

    Fenofibrate improves endothelial function by lipid-lowering and anti-inflammatory effects. Additionally, fenofibrate has been demonstrated to upregulate endothelial nitric oxide synthase (eNOS). AMP-activated protein kinase (AMPK) has been reported to phosphorylate eNOS at Ser-1177 and stimulate vascular endothelium-derived nitric oxide (NO) production. We report here that fenofibrate activates AMPK and increases eNOS phosphorylation and NO production in human umbilical vein endothelial cells (HUVEC). Incubation of HUVEC with fenofibrate increased the phosphorylation of AMPK and acetyl-CoA carboxylase. Fenofibrate simultaneously increased eNOS phosphorylation and NO production. Inhibitors of protein kinase A and phosphatidylinositol 3-kinase failed to suppress the fenofibrate-induced eNOS phosphorylation. Neither bezafibrate nor WY-14643 activated AMPK in HUVEC. Furthermore, fenofibrate activated AMPK without requiring any transcriptional activities. These results indicate that fenofibrate stimulates eNOS phosphorylation and NO production through AMPK activation, which is suggested to be a novel characteristic of this agonist and unrelated to its effects on peroxisome proliferator-activated receptor {alpha}.

  9. Increased serum mitochondrial creatine kinase activity as a risk for hepatocarcinogenesis in chronic hepatitis C patients.

    PubMed

    Enooku, Kenichiro; Nakagawa, Hayato; Soroida, Yoko; Ohkawa, Ryunosuke; Kageyama, Yuko; Uranbileg, Baasanjav; Watanabe, Naoko; Tateishi, Ryosuke; Yoshida, Haruhiko; Koike, Kazuhiko; Yatomi, Yutaka; Ikeda, Hitoshi

    2014-08-15

    Serum mitochondrial creatine kinase (MtCK) activity was reportedly increased in cirrhotic patients although less prominent than that in hepatocellular carcinoma (HCC) patients. To elucidate the clinical significance of serum MtCK activity in chronic liver disease, 171 chronic hepatitis C patients were enrolled. Serum MtCK activity in study subjects was correlated with serum albumin, platelet counts, liver stiffness values and serum aspartate and alanine aminotransferase. In mouse fibrotic liver induced by bile duct ligation, ubiquitous MtCK mRNA and protein expressions were significantly enhanced and its immunoreactivity was increased, predominantly in hepatocytes. During the mean follow-up period of 2.7 years, HCC developed in 21 patients, in whom serum MtCK activity was significantly higher than that in patients without HCC development. Multivariate Cox regression analysis revealed that higher serum MtCK activity was a risk for HCC development. A cutoff value of MtCK for the prediction of HCC development was determined as 9.0 U/L on receiver operating characteristics analysis, where area under receiver operating characteristics curve was 0.754, with a sensitivity of 61.9%, a specificity of 92.8% and a high negative predictive value of 94.2%. Cumulative incidence of HCC was significantly higher in patients with serum MtCK activity of >9.0 U/L compared to those with serum MtCK activity of ≤ 9.0 U/L even in patients with elevated liver stiffness value, >15 kPa. In conclusion, serum MtCK activity may be increased correlatively with the stage of liver fibrosis and hepatocellular damage. Increased serum MtCK activity is an independent risk for hepatocarcinogenesis in chronic hepatitis C patients. PMID:24420733

  10. Daily intake of Lactobacillus casei Shirota increases natural killer cell activity in smokers.

    PubMed

    Reale, Marcella; Boscolo, Paolo; Bellante, Veronica; Tarantelli, Chiara; Di Nicola, Marta; Forcella, Laura; Li, Qing; Morimoto, Kanehisa; Muraro, Raffaella

    2012-07-01

    Dietary probiotics supplementation exerts beneficial health effects. Since cigarette smoking reduces natural killer (NK) activity, we evaluated the effect of Lactobacillus casei Shirota (LcS) intake on NK cytotoxic activity in male smokers. The double-blind, placebo-controlled, randomised study was conducted on seventy-two healthy Italian blue-collar male smokers randomly divided for daily intake of LcS powder or placebo. Before and after 3 weeks of intake, peripheral blood mononuclear cells were isolated and NK activity and CD16⁺ cells' number were assessed. Daily LcS intake for 3 weeks significantly increased NK activity (P < 0.001). The increase in NK activity was paralleled by an increase in CD16⁺ cells (P < 0.001). Before intake, NK cytotoxic activity inversely correlated with the number of cigarettes smoked (R - 0.064). LcS intake prevented the smoke-dependent expected NK activity reduction. The analysis of the distribution of changes in smoke-adjusted NK activity demonstrated that the positive variations were significantly associated with LcS intake, while the negative variations were associated with placebo intake (median value of distributions of differences, 20.98 lytic unit (LU)/10⁷ cells for LcS v. - 4.38 LU/10⁷ cells for placebo, P = 0.039). In conclusion, 3 weeks of daily LcS intake in Italian male smokers was associated with a higher increase in cytotoxic activity and CD16⁺ cells' number in comparison to the placebo intake group. PMID:22142891

  11. Dietary resveratrol administration increases MnSOD expression and activity in mouse brain

    SciTech Connect

    Robb, Ellen L.; Winkelmolen, Lieke; Visanji, Naomi; Brotchie, Jonathan; Stuart, Jeffrey A.

    2008-07-18

    trans-Resveratrol (3,4',5-trihydroxystilbene; RES) is of interest for its reported protective effects in a variety of pathologies, including neurodegeneration. Many of these protective properties have been attributed to the ability of RES to reduce oxidative stress. In vitro studies have shown an increase in antioxidant enzyme activities following exposure to RES, including upregulation of mitochondrial superoxide dismutase, an enzyme that is capable of reducing both oxidative stress and cell death. We sought to determine if a similar increase in endogenous antioxidant enzymes is observed with RES treatment in vivo. Three separate modes of RES delivery were utilized; in a standard diet, a high fat diet and through a subcutaneous osmotic minipump. RES given in a high fat diet proved to be effective in elevating antioxidant capacity in brain resulting in an increase in both MnSOD protein level (140%) and activity (75%). The increase in MnSOD was not due to a substantial proliferation of mitochondria, as RES treatment induced a 10% increase in mitochondrial abundance (Citrate Synthase activity). The potential neuroprotective properties of MnSOD have been well established, and we demonstrate that a dietary delivery of RES is able to increase the expression and activity of this enzyme in vivo.

  12. Methylglyoxal increases cardiomyocyte ischemia-reperfusion injury via glycative inhibition of thioredoxin activity

    PubMed Central

    Wang, Xiao-Liang; Lau, Wayne B.; Yuan, Yue-Xing; Wang, Ya-Jing; Yi, Wei; Christopher, Theodore A.; Lopez, Bernard L.; Liu, Hui-Rong

    2010-01-01

    Diabetes mellitus (DM) is closely related to cardiovascular morbidity and mortality, but the specific molecular basis linking DM with increased vulnerability to cardiovascular injury remains incompletely understood. Methylglyoxal (MG), a precursor to advanced glycation end products (AGEs), is increased in diabetic patient plasma, but its role in diabetic cardiovascular complications is unclear. Thioredoxin (Trx), a cytoprotective molecule with antiapoptotic function, has been demonstrated to be vulnerable to glycative inhibition, but whether Trx is glycatively inhibited by MG, thus contributing to increased cardiac injury, has never been investigated. Cultured H9c2 cardiomyocytes were treated with MG (200 μM) for 6 days. The following were determined pre- and post-simulated ischemia-reperfusion (SI-R; 8 h of hypoxia followed by 3 h of reoxygenation): cardiomyocyte death/apoptosis, Trx expression and activity, AGE formation, Trx-apoptosis-regulating kinase-1 (Trx-ASK1) complex formation, and p38 mitogen-activated protein kinase (MAPK) phosphorylation and activity. Compared with vehicle, MG significantly increased SI-R-induced cardiomyocyte LDH release and apoptosis (P < 0.01). Prior to SI-R, Trx activity was reduced in MG-treated cells, but Trx expression was increased moderately. Moreover, Trx-ASK1 complex formation was reduced, and both p38 MAPK activity and phosphorylation were increased. To investigate the effects of MG on Trx directly, recombinant human Trx (hTrx) was incubated with MG in vitro. Compared with vehicle, MG incubation markedly increased CML formation (a glycation footprint) and inhibited Trx activity. Finally, glycation inhibitor aminoguanidine administration during MG treatment of cultured cells reduced AGE formation, increased Trx activity, restored Trx-ASK1 interaction, and reduced p38 MAPK phosphorylation and activity, caspase-3 activation, and LDH release (P < 0.01). We demonstrated for the first time that methylglyoxal sensitized cultured

  13. Increasing brain angiotensin converting enzyme 2 activity decreases anxiety-like behavior in male mice by activating central Mas receptors.

    PubMed

    Wang, Lei; de Kloet, Annette D; Pati, Dipanwita; Hiller, Helmut; Smith, Justin A; Pioquinto, David J; Ludin, Jacob A; Oh, S Paul; Katovich, Michael J; Frazier, Charles J; Raizada, Mohan K; Krause, Eric G

    2016-06-01

    Over-activation of the brain renin-angiotensin system (RAS) has been implicated in the etiology of anxiety disorders. Angiotensin converting enzyme 2 (ACE2) inhibits RAS activity by converting angiotensin-II, the effector peptide of RAS, to angiotensin-(1-7), which activates the Mas receptor (MasR). Whether increasing brain ACE2 activity reduces anxiety by stimulating central MasR is unknown. To test the hypothesis that increasing brain ACE2 activity reduces anxiety-like behavior via central MasR stimulation, we generated male mice overexpressing ACE2 (ACE2 KI mice) and wild type littermate controls (WT). ACE2 KI mice explored the open arms of the elevated plus maze (EPM) significantly more than WT, suggesting increasing ACE2 activity is anxiolytic. Central delivery of diminazene aceturate, an ACE2 activator, to C57BL/6 mice also reduced anxiety-like behavior in the EPM, but centrally administering ACE2 KI mice A-779, a MasR antagonist, abolished their anxiolytic phenotype, suggesting that ACE2 reduces anxiety-like behavior by activating central MasR. To identify the brain circuits mediating these effects, we measured Fos, a marker of neuronal activation, subsequent to EPM exposure and found that ACE2 KI mice had decreased Fos in the bed nucleus of stria terminalis but had increased Fos in the basolateral amygdala (BLA). Within the BLA, we determined that ∼62% of GABAergic neurons contained MasR mRNA and expression of MasR mRNA was upregulated by ACE2 overexpression, suggesting that ACE2 may influence GABA neurotransmission within the BLA via MasR activation. Indeed, ACE2 overexpression was associated with increased frequency of spontaneous inhibitory postsynaptic currents (indicative of presynaptic release of GABA) onto BLA pyramidal neurons and central infusion of A-779 eliminated this effect. Collectively, these results suggest that ACE2 may reduce anxiety-like behavior by activating central MasR that facilitate GABA release onto pyramidal neurons within the

  14. Curcumin increases gelatinase activity in human neutrophils by a p38 mitogen-activated protein kinase (MAPK)-independent mechanism.

    PubMed

    Antoine, Francis; Girard, Denis

    2015-01-01

    Curcumin has been found to possess anti-inflammatory activities and neutrophils, key players in inflammation, were previously found to be important targets to curcumin in a few studies. For example, curcumin was found to induce apoptosis in neutrophils by a p38 mitogen-activated protein kinase (MAPK)-dependent mechanism. However, the role of curcumin on the biology of neutrophils is still poorly defined. To study the role of curcumin on neutrophil degranulation and to determine the role of p38 MAPK, human neutrophils were freshly isolated from healthy individuals and incubated in vitro with curcumin. Degranulation was studied at three levels: surface expression of granule markers by flow cytometry; release of matrix metallopeptidase-9 (MMP-9 or gelatinase B) enzyme into supernatants by Western blot; and gelatinase B activity by zymography. Activation of p38 MAPK was studied by monitoring its tyrosine phosphorylation levels by western blot and its role by the utilization of a pharmacological inhibitor. The results indicate that curcumin increased the cell surface expression of CD35 (secretory vesicle), CD63 (azurophilic granules), and CD66b (gelatinase granules) in neutrophils. Also, curcumin increased the release and enzymatic activity of gelatinase B in the extracellular milieu and activated p38 MAP kinase in these cells. However, in contrast to fMLP, curcumin-induced enzymatic activity and secretion of gelatinase B were not reversed by use of a p38 inhibitor. Finally, it was found that curcumin was able to enhance phagocytosis. Taken together, the results here demonstrate that curcumin induced degranulation in human neutrophils and that the increased gelatinase activity is not dependent on p38 MAPK activation. Therefore, degranulation is another human neutrophil function that could be modulated by curcumin, as well as phagocytosis. PMID:24926560

  15. Selective Estrogen Receptor Modulation Increases Hippocampal Activity during Probabilistic Association Learning in Schizophrenia

    PubMed Central

    Kindler, Jochen; Weickert, Cynthia Shannon; Skilleter, Ashley J; Catts, Stanley V; Lenroot, Rhoshel; Weickert, Thomas W

    2015-01-01

    People with schizophrenia show probabilistic association learning impairment in conjunction with abnormal neural activity. The selective estrogen receptor modulator (SERM) raloxifene preserves neural activity during memory in healthy older men and improves memory in schizophrenia. Here, we tested the extent to which raloxifene modifies neural activity during learning in schizophrenia. Nineteen people with schizophrenia participated in a twelve-week randomized, double-blind, placebo-controlled, cross-over adjunctive treatment trial of the SERM raloxifene administered orally at 120 mg daily to assess brain activity during probabilistic association learning using functional magnetic resonance imaging (fMRI). Raloxifene improved probabilistic association learning and significantly increased fMRI BOLD activity in the hippocampus and parahippocampal gyrus relative to placebo. A separate region of interest confirmatory analysis in 21 patients vs 36 healthy controls showed a positive association between parahippocampal neural activity and learning in patients, but no such relationship in the parahippocampal gyrus of healthy controls. Thus, selective estrogen receptor modulation by raloxifene concurrently increases activity in the parahippocampal gyrus and improves probabilistic association learning in schizophrenia. These results support a role for estrogen receptor modulation of mesial temporal lobe neural activity in the remediation of learning disabilities in both men and women with schizophrenia. PMID:25829142

  16. Increased Capillary Endothelial Cell Protease Activity in Response to Angiogenic Stimuli in vitro

    NASA Astrophysics Data System (ADS)

    Gross, Janet L.; Moscatelli, David; Rifkin, Daniel B.

    1983-05-01

    Bovine capillary endothelial (BCE) cells produce increased amounts of the proteases plasminogen activator (PA) and latent collagenase when cultured in the presence of the following preparations which are known to contain angiogenic activities: bovine retinal extract, mouse adipocyte conditioned medium, and human hepatoma cell lysate. These preparations stimulated both BCE cell PA and collagenase activities in a dose-dependent manner. Both activities were increased to about the same level by these preparations as by the tumor promoter 12-O-tetradecanoylphorbol 13-acetate. Mitogens that are not angiogenic, such as insulin, epidermal and fibroblast growth factors, and endothelial cell growth supplement, had no effect on BCE cell PA and collagenase activities. Two of the angiogenic preparations (retinal extract and mouse adipocyte-conditioned medium) had no effect on PA activity in endothelial cells derived from bovine aortae (BAE cells). The angiogenic preparations had little (human hepatoma cell lysate, mouse adipocyte-conditioned medium) or no (bovine retinal extract) effect on BAE cell collagenase activities. In the bovine system, the induction of high levels of both PA and collagenase activities by angiogenic preparations is limited to capillary endothelial cells.

  17. Estrogen increases Nrf2 activity through activation of the PI3K pathway in MCF-7 breast cancer cells

    SciTech Connect

    Wu, Juanjuan; Williams, Devin; Walter, Grant A.; Thompson, Winston E.; Sidell, Neil

    2014-11-01

    The actions of the transcription factor Nuclear factor erythroid 2-related factor (Nrf2) in breast cancer have been shown to include both pro-oncogenic and anti-oncogenic activities which is influenced, at least in part, by the hormonal environment. However, direct regulation of Nrf2 by steroid hormones (estrogen and progesterone) has received only scant attention. Nrf2 is known to be regulated by its cytosolic binding protein, Kelch-like ECH-associated protein 1 (Keap1), and by a Keap1-independent mechanism involving a series of phosphorylation steps mediated by phosphatidylinositol 3-kinase (PI3K) and glycogen synthase kinase 3 beta (GSK3β). Here, we report that estrogen (E2) increases Nrf2 activity in MCF7 breast cancer cells through activation of the PI3K/GSK3β pathway. Utilizing antioxidant response element (ARE)-containing luciferase reporter constructs as read-outs for Nrf2 activity, our data indicated that E2 increased ARE activity >14-fold and enhanced the action of the Nrf2 activators, tertiary butylhydroquinone (tBHQ) and sulforaphane (Sul) 4 to 9 fold compared with cells treated with tBHQ or Sul as single agents. This activity was shown to be an estrogen receptor-mediated phenomenon and was antagonized by progesterone. In addition to its action on the reporter constructs, mRNA and protein levels of heme oxygenase 1, an endogenous target gene of Nrf2, was markedly upregulated by E2 both alone and in combination with tBHQ. Importantly, E2-induced Nrf2 activation was completely suppressed by the PI3K inhibitors LY294002 and Wortmannin while the GSK3β inhibitor CT99021 upregulated Nrf2 activity. Confirmation that E2 was, at least partly, acting through the PI3K/GSK3β pathway was indicated by our finding that E2 increased the phosphorylation status of both GSK3β and Akt, a well-characterized downstream target of PI3K. Together, these results demonstrate a novel mechanism by which E2 can regulate Nrf2 activity in estrogen receptor-positive breast cancer

  18. The activity of seminal creatine kinase is increased in the presence of pentoxifylline.

    PubMed

    Banihani, S A; Abu-Alhayjaa, R F

    2016-06-01

    Creatine kinase enzyme (CK) is indispensable for sperm function because it catalyses the regeneration of ATP from the chemical shuttle between creatine and creatine phosphate. Here, we measured CK activity of human spermatozoa in the presence of pentoxifylline (PF), a xanthine derivative drug primarily used to treat peripheral vascular function. Nine semen samples from different males were subjected to swim up, incubated with PF and tested for CK activity using the kinetic spectrophotometric method. The CK activity of spermatozoa significantly increased after addition of PF at 5 mm compared with the control (with 0.0 mm PF). Given that PF has been identified as a sperm motility enhancer and that CK is crucial for adequate sperm motion; then, the aptitude of PF to enhance sperm motility may be modulated by increasing CK activity. PMID:26395279

  19. Increased activity in frontal motor cortex compensates impaired speech perception in older adults

    PubMed Central

    Du, Yi; Buchsbaum, Bradley R.; Grady, Cheryl L.; Alain, Claude

    2016-01-01

    Understanding speech in noisy environments is challenging, especially for seniors. Although evidence suggests that older adults increasingly recruit prefrontal cortices to offset reduced periphery and central auditory processing, the brain mechanisms underlying such compensation remain elusive. Here we show that relative to young adults, older adults show higher activation of frontal speech motor areas as measured by functional MRI during a syllable identification task at varying signal-to-noise ratios. This increased activity correlates with improved speech discrimination performance in older adults. Multivoxel pattern classification reveals that despite an overall phoneme dedifferentiation, older adults show greater specificity of phoneme representations in frontal articulatory regions than auditory regions. Moreover, older adults with stronger frontal activity have higher phoneme specificity in frontal and auditory regions. Thus, preserved phoneme specificity and upregulation of activity in speech motor regions provide a means of compensation in older adults for decoding impoverished speech representations in adverse listening conditions. PMID:27483187

  20. Carbon-Degrading Enzyme Activities Stimulated by Increased Nutrient Availability in Arctic Tundra Soils

    PubMed Central

    Koyama, Akihiro; Wallenstein, Matthew D.; Simpson, Rodney T.; Moore, John C.

    2013-01-01

    Climate-induced warming of the Arctic tundra is expected to increase nutrient availability to soil microbes, which in turn may accelerate soil organic matter (SOM) decomposition. We increased nutrient availability via fertilization to investigate the microbial response via soil enzyme activities. Specifically, we measured potential activities of seven enzymes at four temperatures in three soil profiles (organic, organic/mineral interface, and mineral) from untreated native soils and from soils which had been fertilized with nitrogen (N) and phosphorus (P) since 1989 (23 years) and 2006 (six years). Fertilized plots within the 1989 site received annual additions of 10 g N⋅m-2⋅year-1 and 5 g P⋅m-2⋅year-1. Within the 2006 site, two fertilizer regimes were established – one in which plots received 5 g N⋅m-2⋅year-1 and 2.5 g P⋅m-2⋅year-1 and one in which plots received 10 g N⋅m-2⋅year-1 and 5 g P⋅m-2⋅year-1. The fertilization treatments increased activities of enzymes hydrolyzing carbon (C)-rich compounds but decreased phosphatase activities, especially in the organic soils. Activities of two enzymes that degrade N-rich compounds were not affected by the fertilization treatments. The fertilization treatments increased ratios of enzyme activities degrading C-rich compounds to those for N-rich compounds or phosphate, which could lead to changes in SOM chemistry over the long term and to losses of soil C. Accelerated SOM decomposition caused by increased nutrient availability could significantly offset predicted increased C fixation via stimulated net primary productivity in Arctic tundra ecosystems. PMID:24204773

  1. Carbon-degrading enzyme activities stimulated by increased nutrient availability in Arctic tundra soils.

    PubMed

    Koyama, Akihiro; Wallenstein, Matthew D; Simpson, Rodney T; Moore, John C

    2013-01-01

    Climate-induced warming of the Arctic tundra is expected to increase nutrient availability to soil microbes, which in turn may accelerate soil organic matter (SOM) decomposition. We increased nutrient availability via fertilization to investigate the microbial response via soil enzyme activities. Specifically, we measured potential activities of seven enzymes at four temperatures in three soil profiles (organic, organic/mineral interface, and mineral) from untreated native soils and from soils which had been fertilized with nitrogen (N) and phosphorus (P) since 1989 (23 years) and 2006 (six years). Fertilized plots within the 1989 site received annual additions of 10 g N · m(-2) · year(-1) and 5 g P · m(-2) · year(-1). Within the 2006 site, two fertilizer regimes were established--one in which plots received 5 g N · m(-2) · year(-1) and 2.5 g P · m(-2) · year(-1) and one in which plots received 10 g N · m(-2) · year(-1) and 5 g P · m(-2) · year(-1). The fertilization treatments increased activities of enzymes hydrolyzing carbon (C)-rich compounds but decreased phosphatase activities, especially in the organic soils. Activities of two enzymes that degrade N-rich compounds were not affected by the fertilization treatments. The fertilization treatments increased ratios of enzyme activities degrading C-rich compounds to those for N-rich compounds or phosphate, which could lead to changes in SOM chemistry over the long term and to losses of soil C. Accelerated SOM decomposition caused by increased nutrient availability could significantly offset predicted increased C fixation via stimulated net primary productivity in Arctic tundra ecosystems. PMID:24204773

  2. Construction of Mutant Glucose Oxidases with Increased Dye-Mediated Dehydrogenase Activity

    PubMed Central

    Horaguchi, Yohei; Saito, Shoko; Kojima, Katsuhiro; Tsugawa, Wakako; Ferri, Stefano; Sode, Koji

    2012-01-01

    Mutagenesis studies on glucose oxidases (GOxs) were conducted to construct GOxs with reduced oxidase activity and increased dehydrogenase activity. We focused on two representative GOxs, of which crystal structures have already been reported—Penicillium amagasakiense GOx (PDB ID; 1gpe) and Aspergillus niger GOx (PDB ID; 1cf3). We constructed oxygen-interacting structural models for GOxs, and predicted the residues responsible for oxidative half reaction with oxygen on the basis of the crystal structure of cholesterol oxidase as well as on the fact that both enzymes are members of the glucose/methanol/choline (GMC) oxidoreductase family. Rational amino acid substitution resulted in the construction of an engineered GOx with drastically decreased oxidase activity and increased dehydrogenase activity, which was higher than that of the wild-type enzyme. As a result, the dehydrogenase/oxidase ratio of the engineered enzyme was more than 11-fold greater than that of the wild-type enzyme. These results indicate that alteration of the dehydrogenase/oxidase activity ratio of GOxs is possible by introducing a mutation into the putative functional residues responsible for oxidative half reaction with oxygen of these enzymes, resulting in a further increased dehydrogenase activity. This is the first study reporting the alteration of GOx electron acceptor preference from oxygen to an artificial electron acceptor. PMID:23203056

  3. Diagnosis and characterization of mania: Quantifying increased energy and activity in the human behavioral pattern monitor.

    PubMed

    Perry, William; McIlwain, Meghan; Kloezeman, Karen; Henry, Brook L; Minassian, Arpi

    2016-06-30

    Increased energy or activity is now an essential feature of the mania of Bipolar Disorder (BD) according to DSM-5. This study examined whether objective measures of increased energy can differentiate manic BD individuals and provide greater diagnostic accuracy compared to rating scales, extending the work of previous studies with smaller samples. We also tested the relationship between objective measures of energy and rating scales. 50 hospitalized manic BD patients were compared to healthy subjects (HCS, n=39) in the human Behavioral Pattern Monitor (hBPM) which quantifies motor activity and goal-directed behavior in an environment containing novel stimuli. Archival hBPM data from 17 schizophrenia patients were used in sensitivity and specificity analyses. Manic BD patients exhibited higher motor activity than HCS and higher novel object interactions. hBPM activity measures were not correlated with observer-rated symptoms, and hBPM activity was more sensitive in accurately classifying hospitalized BD subjects than observer ratings. Although the findings can only be generalized to inpatient populations, they suggest that increased energy, particularly specific and goal-directed exploration, is a distinguishing feature of BD mania and is best quantified by objective measures of motor activity. A better understanding is needed of the biological underpinnings of this cardinal feature. PMID:27138818

  4. Texting to Increase Physical Activity Among Teenagers (TXT Me!): Rationale, Design, and Methods Proposal

    PubMed Central

    Cantu, Dora; Bhatt, Riddhi; Baranowski, Tom; Rodgers, Wendy; Jago, Russell; Anderson, Barbara; Liu, Yan; Mendoza, Jason A; Tapia, Ramsey; Buday, Richard

    2014-01-01

    Background Physical activity decreases from childhood through adulthood. Among youth, teenagers (teens) achieve the lowest levels of physical activity, and high school age youth are particularly at risk of inactivity. Effective methods are needed to increase youth physical activity in a way that can be maintained through adulthood. Because teens text a great deal, text messages promoting walking, a low cost physical activity, may be an effective method for promoting sustainable physical activity. Objective The objective of our study was to determine the effect of pedometers, self selected step goals, and texts grounded in the self-determination theory (SDT) on physical activity among the teens. Methods “TXT Me!” was a 12 week intervention that texted 14-17 year olds to increase their daily physical activity by increasing the number of steps they take each day. The intervention was grounded in the SDT. Formative research with the teens helped construct the intervention and develop the texts. A total of 84 texts were developed (12 to set a step goal, and 72 promoting autonomy, competence, and relatedness). The pilot evaluation used a four group, randomized design (n=160). After baseline data collection, the participants were randomized to one of four conditions (no treatment control, pedometer only, pedometer + weekly prompts, pedometer + weekly prompts + SDT grounded texts). Data were collected at baseline and immediately upon completion of the study. The primary outcome was physical activity, measured by 7 days of accelerometry. Basic psychological needs, physical activity motivation, process evaluation, and program satisfaction data were also collected. Results To our knowledge, this is one of the first studies to explore the use of stand alone, SDT grounded texts, supported by pedometers and prompts to set a self selected step goal, as a method for increasing physical activity among teens. Conclusions This pilot study will contribute valuable information

  5. ACROLEIN ACTIVATES MATRIX METALLOPROTEINASES BY INCREASING REACTIVE OXYGEN SPECIES IN MACROPHAGES

    PubMed Central

    O’Toole, Timothy E.; Zheng, Yu-Ting; Hellmann, Jason; Conklin, Daniel J.; Barski, Oleg; Bhatnagar, Aruni

    2009-01-01

    Acrolein is a ubiquitous component of environmental pollutants such as automobile exhaust, cigarette, wood, and coal smoke. It is also a natural constituent of several foods and is generated endogenously during inflammation or oxidation of unsaturated lipids. Because increased inflammation and episodic exposure to acrolein-rich pollutants such as traffic emissions or cigarette smoke have been linked to acute myocardial infarction, we examined the effects of acrolein on matrix metalloproteinases (MMPs), which destabilize atherosclerotic plaques. Our studies show that exposure to acrolein resulted in the secretion of MMP-9 from differentiated THP-1 macrophages. Acrolein-treatment of macrophages also led to an increase in reactive oxygen species (ROS), free intracellular calcium ([Ca2+]i), and xanthine oxidase (XO) activity. ROS production was prevented by allopurinol, but not by rotenone or apocynin and by buffering changes in [Ca2+]I with BAPTA-AM. The increase in MMP production was abolished by pre-treatment with the antioxidants Tiron and N-acetyl cysteine (NAC) or with the xanthine oxidase inhibitors allopurinol or oxypurinol. Finally, MMP activity was significantly stimulated in aortic sections from apoE-null mice containing advanced atherosclerotic lesions after exposure to acrolein ex vivo. These observations suggest that acrolein exposure results in MMP secretion from macrophages via a mechanism that involves an increase in [Ca2+]I, leading to xanthine oxidase activation and an increase in ROS production. ROS-dependent activation of MMPs by acrolein could destabilize atherosclerotic lesions during brief episodes of inflammation or pollutant exposure. PMID:19371603

  6. Acrolein activates matrix metalloproteinases by increasing reactive oxygen species in macrophages.

    PubMed

    O'Toole, Timothy E; Zheng, Yu-Ting; Hellmann, Jason; Conklin, Daniel J; Barski, Oleg; Bhatnagar, Aruni

    2009-04-15

    Acrolein is a ubiquitous component of environmental pollutants such as automobile exhaust, cigarette, wood, and coal smoke. It is also a natural constituent of several foods and is generated endogenously during inflammation or oxidation of unsaturated lipids. Because increased inflammation and episodic exposure to acrolein-rich pollutants such as traffic emissions or cigarette smoke have been linked to acute myocardial infarction, we examined the effects of acrolein on matrix metalloproteinases (MMPs), which destabilize atherosclerotic plaques. Our studies show that exposure to acrolein resulted in the secretion of MMP-9 from differentiated THP-1 macrophages. Acrolein-treatment of macrophages also led to an increase in reactive oxygen species (ROS), free intracellular calcium ([Ca2+](i)), and xanthine oxidase (XO) activity. ROS production was prevented by allopurinol, but not by rotenone or apocynin and by buffering changes in [Ca2+](I) with BAPTA-AM. The increase in MMP production was abolished by pre-treatment with the antioxidants Tiron and N-acetyl cysteine (NAC) or with the xanthine oxidase inhibitors allopurinol or oxypurinol. Finally, MMP activity was significantly stimulated in aortic sections from apoE-null mice containing advanced atherosclerotic lesions after exposure to acrolein ex vivo. These observations suggest that acrolein exposure results in MMP secretion from macrophages via a mechanism that involves an increase in [Ca2+](I), leading to xanthine oxidase activation and an increase in ROS production. ROS-dependent activation of MMPs by acrolein could destabilize atherosclerotic lesions during brief episodes of inflammation or pollutant exposure. PMID:19371603

  7. Less precise motor control leads to increased agonist-antagonist muscle activation during stick balancing.

    PubMed

    Reeves, N Peter; Popovich, John M; Vijayanagar, Vilok; Pathak, Pramod K

    2016-06-01

    Human motor control has constraints in terms of its responsiveness, which limit its ability to successfully perform tasks. In a previous study, it was shown that the ability to balance an upright stick became progressively more challenging as the natural frequency (angular velocity without control) of the stick increased. Furthermore, forearm and trunk agonist and antagonist muscle activation increased as the natural frequency of the stick increased, providing evidence that the central nervous system produces agonist-antagonist muscle activation to match task dynamics. In the present study, visual feedback of the stick position was influenced by changing where subject focused on the stick during stick balancing. It was hypothesized that a lower focal height would degrade motor control (more uncertainty in tracking stick position), thus making balancing more challenging. The probability of successfully balancing the stick at four different focal heights was determined along with the average angular velocity of the stick. Electromyographic signals from forearm and trunk muscles were also recorded. As expected, the probability of successfully balancing the stick decreased and the average angular velocity of the stick increased as subjects focused lower on the stick. In addition, changes in the level of agonist and antagonist muscle activation in the forearm and trunk was linearly related to changes in the angular velocity of the stick during balancing. One possible explanation for this is that the central nervous system increases muscle activation to account for less precise motor control, possibly to improve the responsiveness of human motor control. PMID:27010497

  8. Brain-derived neurotrophic factor rapidly increases NMDA receptor channel activity through Fyn-mediated phosphorylation.

    PubMed

    Xu, Fei; Plummer, Mark R; Len, Guo-Wei; Nakazawa, Takanobu; Yamamoto, Tadashi; Black, Ira B; Wu, Kuo

    2006-11-22

    Brain-derived neurotrophic factor (BDNF) is a potent modulator of hippocampal synaptic plasticity. Previously, we found that one of the targets of BDNF modulation is NR2B-containing NMDA receptors. Furthermore, exposure to the trophin rapidly increases NMDA receptor activity and enhances tyrosine phosphorylation of NR2B in cortical and hippocampal postsynaptic densities (PSDs), potentially linking receptor phosphorylation to synaptic plasticity. To define the specific NR2B residue(s) regulated by BDNF, we focused on tyrosine 1472, phosphorylation of which increases after LTP. BDNF rapidly increased phosphorylation in cortical PSDs. The tyrosine kinase Fyn is critical since BDNF-dependent phosphorylation was abolished in Fyn knockout mice. Single-channel patch clamp recordings showed that Fyn is required for the increase in NMDA receptor activity elicited by BDNF. Collectively, our results suggest that BDNF enhances phosphorylation of NR2B tyrosine 1472 through activation of Fyn, leading to alteration of NMDA receptor activity and increased synaptic transmission. PMID:17045972

  9. Let's Move for Pacific Islander Communities: an Evidence-Based Intervention to Increase Physical Activity.

    PubMed

    LaBreche, Mandy; Cheri, Ashley; Custodio, Harold; Fex, Cleo Carlos; Foo, Mary Anne; Lepule, Jonathan Tana; May, Vanessa Tui'one; Orne, Annette; Pang, Jane Ka'ala; Pang, Victor Kaiwi; Sablan-Santos, Lola; Schmidt-Vaivao, Dorothy; Surani, Zul; Talavou, Melevesi Fifita; Toilolo, Tupou; Palmer, Paula Healani; Tanjasiri, Sora Park

    2016-06-01

    Pacific Islander (PI) populations of Southern California experience high obesity and low physical activity levels. Given PI's rich cultural ties, efforts to increase physical activity using a community-tailored strategy may motivate members in a more sustainable manner. In this paper, we (1) detail the program adaptation methodology that was utilized to develop the Weaving an Islander Network for Cancer Awareness, Research and Training (WINCART) Center's PI Let's Move Program, a culturally tailored program aimed to increase physical activity levels among members of PI organizations in Southern California, and (2) share the program's pilot evaluation results on individual and organizational changes. The WINCART Center applied the National Cancer Institute's program adaptation guidelines to tailor the evidence-based Instant Recess program to fit the needs of PIs. The end product, the PI Let's Move Program, was piloted in 2012 with eight PI organizations, reaching 106 PI adults. At baseline, 52 % of participants reported that they were not physically active, with the average number of days engaged in medium-intensity physical activity at 2.09 days/week. After the 2-month program, participants increased the number of days that they engaged in medium-intensity physical activity from 2.09 to 2.90 days/week. Post-pilot results found that 82 % of participants reported intentions to engage in physical activity for at least the next 6 months. At baseline, only one organization was currently implementing a physical activity program, and none had implemented an evidence-based physical activity program tailored for PIs. After the 2-month timeframe, despite varying levels of capacity, all eight organizations were able to successfully implement the program. In conclusion, results from our program provide evidence that disparity populations, such as PIs, can be successfully reached through programs that are culturally tailored to both individuals and their community

  10. Spirulina elicits the activation of innate immunity and increases resistance against Vibrio alginolyticus in shrimp.

    PubMed

    Chen, Yu-Yuan; Chen, Jiann-Chu; Tayag, Carina Miranda; Li, Hui-Fang; Putra, Dedi Fazriansyah; Kuo, Yi-Hsuan; Bai, Jia-Chin; Chang, Yu-Hsuan

    2016-08-01

    The effect of Spirulina dried powder (SDP) on the immune response of white shrimp Litopenaeus vannamei was studied in vitro and in vivo. Incubating shrimp haemocytes in 0.5 mg ml(-1) SDP caused the degranulation of haemocytes and a reduction in the percentage of large cells within 30 min. Shrimp haemocytes incubated in 1 mg ml(-1) SDP significantly increased their phenoloxidase (PO) activity, serine proteinase activity, and respiratory burst activity (RB, release of superoxide anion). A recombinant protein of lipopolysaccharide and β-1,3-glucan binding protein (LGBP) of the white shrimp was produced, named rLvLGBP, and examined for its binding with SDP. An ELISA binding assay showed that rLvLGBP binds to SDP with a dissociation constant of 0.0507 μM. In another experiment, shrimp fed diets containing SDP at 0 (control), 30, and 60 g kg(-1) after four weeks were examined for LGBP transcript level and lysozyme activity, as well as phagocytic activity, clearance efficiency, and resistance to Vibrio alginolyticus. These parameters were significantly higher in shrimp receiving diets containing SDP at 60 g kg(-1) or 30 g kg(-1) than in controls. In conclusion, shrimp haemocytes receiving SDP provoked the activation of innate immunity as evidenced by the recognition and binding of LGBP, degranulation of haemocytes, reduction in the percentage of large cells, increases in PO activity, serine proteinase activity, superoxide anion levels, and up-regulated LGBP transcript levels. Shrimp receiving diets containing SDP had increased lysozyme activity and resistance against V. alginolyticus infection. This study showed the mechanism underlying the immunostimulatory action of Spirulina and its immune response in shrimp. PMID:27368541

  11. Evidence that elevated CO2 levels can indirectly increase rhizosphere denitrifier activity

    NASA Technical Reports Server (NTRS)

    Smart, D. R.; Ritchie, K.; Stark, J. M.; Bugbee, B.

    1997-01-01

    We examined the influence of elevated CO2 concentration on denitrifier enzyme activity in wheat rhizoplanes by using controlled environments and solution culture techniques. Potential denitrification activity was from 3 to 24 times higher on roots that were grown under an elevated CO2 concentration of 1,000 micromoles of CO2 mol-1 than on roots grown under ambient levels of CO2. Nitrogen loss, as determined by a nitrogen mass balance, increased with elevated CO2 levels in the shoot environment and with a high NO3- concentration in the rooting zone. These results indicated that aerial CO2 concentration can play a role in rhizosphere denitrifier activity.

  12. NDM-4 Metallo-β-Lactamase with Increased Carbapenemase Activity from Escherichia coli

    PubMed Central

    Boulanger, Anne E.; Poirel, Laurent

    2012-01-01

    A clinical Escherichia coli isolate resistant to all β-lactams, including carbapenems, expressed a novel metallo-β-lactamase (MBL), NDM-4, differing from NDM-1 by a single amino acid substitution (Met154Leu). NDM-4 possessed increased hydrolytic activity toward carbapenems and several cephalosporins compared to that of NDM-1. This amino acid substitution was not located in the known active sites of NDM-1, indicating that remote amino acid substitutions might also play a role in the extended activity of this MBL. PMID:22252797

  13. Evidence that elevated CO2 levels can indirectly increase rhizosphere denitrifier activity.

    PubMed Central

    Smart, D R; Ritchie, K; Stark, J M; Bugbee, B

    1997-01-01

    We examined the influence of elevated CO2 concentration on denitrifier enzyme activity in wheat rhizoplanes by using controlled environments and solution culture techniques. Potential denitrification activity was from 3 to 24 times higher on roots that were grown under an elevated CO2 concentration of 1,000 micromoles of CO2 mol-1 than on roots grown under ambient levels of CO2. Nitrogen loss, as determined by a nitrogen mass balance, increased with elevated CO2 levels in the shoot environment and with a high NO3- concentration in the rooting zone. These results indicated that aerial CO2 concentration can play a role in rhizosphere denitrifier activity. PMID:11536820

  14. TRAIL-induced caspase/p38 activation is responsible for the increased catalytic and invasive activities of Akt

    PubMed Central

    SUN, BO K.; KIM, JOO-HANG; NGUYEN, HOAN N.; KIM, SO Y.; OH, SEEUN; LEE, YONG J.; SONG, JAE J.

    2010-01-01

    We previously observed that TRAIL induces acquired TRAIL resistance coinciding with increased Akt phosphorylation brought about by the Src-PI3K-Akt signaling pathways and mediated by c-Cbl. c-Cbl, a ubiquitously expressed cytoplasmic adaptor protein, is simultaneously involved in the rapid degradation of TRAIL receptors and Akt phosphorylation during TRAIL treatment. Here, we show that Akt phosphorylation is not exclusively responsible for acquired TRAIL resistance. Akt catalytic activation is known to increase during metabolic oxidative stress, but we show that TRAIL also dramatically induces the catalytic activation of Akt in TRAIL-sensitive cells, but not in TRAIL-resistant cells. This suggests that Akt catalytic activation during TRAIL-induced apoptosis is likely to play a compensatory role in the maintenance of cell homeostasis. In addition, activated p38 and phosphorylated HSP27 were found to act as downstream effector molecules of p38 during TRAIL treatment and were shown to be responsible for increased Akt catalytic and invasive activities. PMID:21109947

  15. Dihydrolipoic acid activates oligomycin-sensitive thiol groups and increases ATP synthesis in mitochondria.

    PubMed

    Zimmer, G; Mainka, L; Krüger, E

    1991-08-01

    Investigations with dihydrolipoic acid in rat heart mitochondria and mitoplasts reveal an activation of ATP-synthase up to 45%, whereas ATPase activities decrease by 36%. In parallel with an increase in ATP synthesis oligomycin-sensitive mitochondrial -SH groups are activated at 2-4 nmol dihydrolipoic acid/mg protein. ATPase activation by the uncouplers carbonylcyanide-p-trifluoromethoxyphenylhydrazone and oleate is diminished by dihydrolipoic acid, and ATP synthesis depressed by oleate is partially restored. No such efficiency of dihydrolipoic acid is seen with palmitate-induced ATPase activation or decrease of ATP synthesis. This indicates different interference of oleate and palmitate with mitochondria. In addition to its known coenzymatic properties dihydrolipoic acid may act as a substitute for coenzyme A, thereby diminishing the uncoupling efficiency of oleate. Furthermore, dihydrolipoic acid is a very potent antioxidant, shifting the -SH-S-S- equilibrium in mitochondria to the reduced state and improving the energetic state of cells. PMID:1832845

  16. Increased premotor cortex activation in high functioning autism during action observation.

    PubMed

    Perkins, Tom J; Bittar, Richard G; McGillivray, Jane A; Cox, Ivanna I; Stokes, Mark A

    2015-04-01

    The mirror neuron (MN) hypothesis of autism has received considerable attention, but to date has produced inconsistent findings. Using functional MRI, participants with high functioning autism or Asperger's syndrome were compared to typically developing individuals (n=12 in each group). Participants passively observed hand gestures that included waving, pointing, and grasping. Concerning the MN network, both groups activated similar regions including prefrontal, inferior parietal and superior temporal regions, with the autism group demonstrating significantly greater activation in the dorsal premotor cortex. Concerning other regions, participants with autism demonstrated increased activity in the anterior cingulate and medial frontal gyrus, and reduced activation in calcarine, cuneus, and middle temporal gyrus. These results suggest that during observation of hand gestures, frontal cortex activation is affected in autism, which we suggest may be linked to abnormal functioning of the MN system. PMID:25726458

  17. The Increasing Impact of Activity-Based Protein Profiling in Plant Science.

    PubMed

    Morimoto, Kyoko; van der Hoorn, Renier A L

    2016-03-01

    The active proteome dictates plant physiology. Yet, active proteins are difficult to predict based on transcript or protein levels, because protein activities are regulated post-translationally in their microenvironments. Over the past 10 years, activity-based protein profiling (ABPP) is increasingly used in plant science. ABPP monitors the activities of hundreds of plant proteins using tagged chemical probes that react with the active site of proteins in a mechanism-dependent manner. Since labeling is covalent and irreversible, labeled proteins can be detected and identified on protein gels and by mass spectrometry using tagged fluorophores and/or biotin. Here, we discuss general concepts, approaches and practical considerations of ABPP, before we summarize the discoveries made using 40 validated probes representing 14 chemotypes that can monitor the active state of >4,500 plant proteins. These discoveries and new opportunities indicate that this emerging functional proteomic technology is a powerful discovery tool that will have an increasing impact on plant science. PMID:26872839

  18. Aging of whiskey increases 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity.

    PubMed

    Aoshima, Hitoshi; Tsunoue, Hideaki; Koda, Hirofumi; Kiso, Yoshinobu

    2004-08-11

    1,1-Diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity of Japanese whiskey after various aging periods in oak barrels was measured to evaluate the antioxidative effects of whiskey. The activity of the whiskey increased with the aging period with high correlation. The activity of various types of whiskey was measured and shown to be correlated to the potentiation of the GABAA receptor response measured in a previous paper. However, the fragrant compounds in the whiskey which potentiated the GABAA receptor response had low DPPH radical scavenging activity, while phenol derivatives had high radical scavenging activity. The whiskey was extracted by pentane. The aqueous part showed the scavenging activity, whereas the pentane part did not. Thus, both the DPPH radical scavenging activity and the potentiation of the GABAA receptor response increased during whiskey aging in oak barrels, but were due to different components. The whiskey protected the H2O2-induced death of E. coli more than ethanol at the same concentration as that of the whiskey. The changes that occurred in the whiskey during aging may be the reason aged whiskies are so highly valued. PMID:15291502

  19. Increasing cleavage specificity and activity of restriction endonuclease KpnI

    PubMed Central

    Vasu, Kommireddy; Nagamalleswari, Easa; Zahran, Mai; Imhof, Petra; Xu, Shuang-yong; Zhu, Zhenyu; Chan, Siu-Hong; Nagaraja, Valakunja

    2013-01-01

    Restriction enzyme KpnI is a HNH superfamily endonuclease requiring divalent metal ions for DNA cleavage but not for binding. The active site of KpnI can accommodate metal ions of different atomic radii for DNA cleavage. Although Mg2+ ion higher than 500 μM mediates promiscuous activity, Ca2+ suppresses the promiscuity and induces high cleavage fidelity. Here, we report that a conservative mutation of the metal-coordinating residue D148 to Glu results in the elimination of the Ca2+-mediated cleavage but imparting high cleavage fidelity with Mg2+. High cleavage fidelity of the mutant D148E is achieved through better discrimination of the target site at the binding and cleavage steps. Biochemical experiments and molecular dynamics simulations suggest that the mutation inhibits Ca2+-mediated cleavage activity by altering the geometry of the Ca2+-bound HNH active site. Although the D148E mutant reduces the specific activity of the enzyme, we identified a suppressor mutation that increases the turnover rate to restore the specific activity of the high fidelity mutant to the wild-type level. Our results show that active site plasticity in coordinating different metal ions is related to KpnI promiscuous activity, and tinkering the metal ion coordination is a plausible way to reduce promiscuous activity of metalloenzymes. PMID:23963701

  20. Glucagon increases energy expenditure independently of brown adipose tissue activation in humans

    PubMed Central

    Salem, V; Izzi-Engbeaya, C; Coello, C; Thomas, D B; Chambers, E S; Comninos, A N; Buckley, A; Win, Z; Al-Nahhas, A; Rabiner, E A; Gunn, R N; Budge, H; Symonds, M E; Bloom, S R; Tan, T M; Dhillo, W S

    2016-01-01

    Aims To investigate, for a given energy expenditure (EE) rise, the differential effects of glucagon infusion and cold exposure on brown adipose tissue (BAT) activation in humans. Methods Indirect calorimetry and supraclavicular thermography was performed in 11 healthy male volunteers before and after: cold exposure; glucagon infusion (at 23 °C); and vehicle infusion (at 23 °C). All volunteers underwent 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET)/CT scanning with cold exposure. Subjects with cold-induced BAT activation on 18F-FDG PET/CT (n = 8) underwent a randomly allocated second 18F-FDG PET/CT scan (at 23 °C), either with glucagon infusion (n = 4) or vehicle infusion (n = 4). Results We observed that EE increased by 14% after cold exposure and by 15% after glucagon infusion (50 ng/kg/min; p < 0.05 vs control for both). Cold exposure produced an increase in neck temperature (+0.44 °C; p < 0.001 vs control), but glucagon infusion did not alter neck temperature. In subjects with a cold-induced increase in the metabolic activity of supraclavicular BAT on 18F-FDG PET/CT, a significant rise in the metabolic activity of BAT after glucagon infusion was not detected. Cold exposure increased sympathetic activation, as measured by circulating norepinephrine levels, but glucagon infusion did not. Conclusions Glucagon increases EE by a similar magnitude compared with cold activation, but independently of BAT thermogenesis. This finding is of importance for the development of safe treatments for obesity through upregulation of EE. PMID:26434748

  1. Increase in the activities of glycolytic enzymes in rat lungs produced by nitrogen dioxide

    SciTech Connect

    Mochitate, K.; Miura, T.; Kubota, K.

    1985-01-01

    Male Jcl: Wistar rats were exposed to 2, 4, and 10 ppm NO/sub 2/ for 14, 10, and 7 d, respectively, to examine the effect of NO/sub 2/ on the lung glycolytic pathway, a major energy-generating system in the lung. A highly significant increase in the activities of hexokinase, phosphofructokinase, 3-phosphoglycerate kinase, pyruvate kinase (PK), and lactate dehydrogenase was observed after 5 d exposure to 10 ppm NO/sub 2/, and a significantly higher value was maintained until d 7. Similarly, the activities of all enzymes examined increased significantly by exposure to 4 ppm NO/sub 2/, reaching the maximum between 4 and 7 d of exposure, and then approached to near the control levels. The most remarkable increase was found in the PK activity, which reached 1.82- and 1.53-fold that of the control at d 5 (10 ppm) and d 7 (4 ppm) of exposure, respectively. Upon exposure to 2 ppm NO/sub 2/, the PK activity of exposed animals was also increased to 1.23-fold that of the control at d 7, and higher activity was maintained until d 14. The glucose-6-phosphate dehydrogenase activity of exposed animals increased significantly at d 3, 4, and 14 of exposures to 10, 4, and 2 ppm NO/sub 2/, respectively, and a significantly higher value was maintained in the following period of exposure. These results show that short-term exposure of rats to 2-10 ppm NO/sub 2/ induces the pulmonary systems concerning glycolysis and NADPH-generation. The generation of energy and NADPH in the lung may be enhanced by NO/sub 2/ inhalation.

  2. Reactive oxygen species mediate TNFR1 increase after TRPV1 activation in mouse DRG neurons

    PubMed Central

    Ma, Fei; Zhang, Liping; Westlund, Karin N

    2009-01-01

    Background Transient receptor potential vanilloid subtype 1 (TRPV1) is activated by low pH/protons and is well known to be involved in hyperalgesia during inflammation. Tumor necrosis factor α (TNF-α), a proinflammatory cytokine, is involved in nociceptive responses causing hyperalgesia through TNF receptor type 1 (TNFR1) activation. Reactive oxygen species (ROS) production is also prominently increased in inflamed tissue. The present study investigated TNFR1 receptors in primary cultured mouse dorsal root ganglion (DRG) neurons after TRPV1 activation and the involvement of ROS. C57BL/6 mice, both TRPV1 knockout and wild type, were used for immunofluorescent and live cell imaging. The L4 and L5 DRGs were dissected bilaterally and cultured overnight. TRPV1 was stimulated with capsaicin or its potent analog, resiniferatoxin. ROS production was measured with live cell imaging and TNFR1 was detected with immunofluorescence in DRG primary cultures. The TRPV1 knockout mice, TRPV1 antagonist, capsazepine, and ROS scavenger, N-tert-Butyl-α-phenylnitrone (PBN), were employed to explore the functional relationship among TRPV1, ROS and TNFR1 in these studies. Results The results demonstrate that TRPV1 activation increases TNFR1 receptors and ROS generation in primary cultures of mouse DRG neurons. Activated increases in TNFR1 receptors and ROS production are absent in TRPV1 deficient mice. The PBN blocks increases in TNFR1 and ROS production induced by capsaicin/resiniferatoxin. Conclusion TRPV1 activation increases TNFR1 in cultured mouse DRG neurons through a ROS signaling pathway, a novel sensitization mechanism in DRG neurons. PMID:19531269

  3. Fatty acids and glucose increase neutral endopeptidase activity in human microvascular endothelial cells.

    PubMed

    Muangman, Pornprom; Spenny, Michelle L; Tamura, Richard N; Gibran, Nicole S

    2003-06-01

    Neutral endopeptidase (NEP), a membrane-bound metallopeptidase enzyme that degrades neuropeptides, bradykinin, atrial natriuretic factor, enkephalins, and endothelin may regulate response to injury. We have previously demonstrated increased NEP localization and enzyme activity in diabetic wounds and skin compared with normal controls. We hypothesized that hyperlipidemia and hyperglycemia associated with type 2 diabetes mellitus may induce excessive NEP activity and thereby diminish normal response to injury. Human microvascular endothelial cells were treated with five different fatty acids (40 microM) with varying degrees of saturation, including oleic acid, linoleic acid, palmitic acid, stearic acid, and linolenic acid and/or glucose (40 mM) for 48 h. The effect of the antioxidative agents vitamin E and C on NEP enzyme activation was determined by treating the cultured cells with alpha-tocopherol succinate and/or L-ascorbic acid. Cell membrane preparations were assayed for NEP activity by incubation with glutaryl-Ala-Ala-Phe-4-methoxy-beta naphthylamide to generate a fluorescent degradation product methoxy 2 naphthylamine. High glucose or fatty acid concentration upregulated NEP activity. The highest NEP activity was observed with combined elevated glucose, linoleic acid, and oleic acid (P < 0.05). Antioxidant vitamin E and C treatment significantly reduced NEP enzyme activity after fatty acid exposure (P < 0.05). Thus, hyperglycemia and hyperlipidemia associated with type 2 diabetes mellitus may increase endothelial cell NEP activity and thereby decrease early pro-inflammatory responses. The modulator effect of vitamin E and C on NEP membrane enzyme activity after exposure to fatty acid stimulation suggests that lipid oxidation may activate NEP. PMID:12785004

  4. Men on the Move: A Pilot Program to Increase Physical Activity Among African American Men

    PubMed Central

    Griffith, Derek M.; Allen, Julie Ober; Johnson-Lawrence, Vicki; Langford, Aisha

    2015-01-01

    Despite the important contribution increasing physical activity levels may play in reducing chronic disease morbidity and mortality, there is a paucity of interventions and research indicating how to improve physical activity levels in African American men. Men on the Move was a pilot study to increase African American men’s levels of physical activity by improving access to age and ability-appropriate, male-focused physical activity opportunities and facilitating access to social support from male peers. Forty-one African American men ages 35 to 70 enrolled (mean age = 53.8). Groups of 5 to 10 men met once a week with a certified personal trainer for 10 weeks. Each meeting addressed barriers to physical activity, provided men with community resources, and incorporated activities that promoted flexibility, strength, balance, and conditioning. Improvements (p < .05) were detected for the following outcome measures: perceived self-efficacy to sustain physical activity, endurance, overall health status, and stress level. Physiological and fitness outcome measures improved, although not to significant levels. Whereas 40% of the men met the recommendation of 150 minutes of moderate or vigorous physical activity weekly at baseline, 68% of the men met this recommendation by the end of the project. These positive results attest to the feasibility of successfully engaging middle-aged and older African American men in a physical activity intervention, and our findings demonstrate the initial efficacy of this intervention approach. More research is needed that includes a more intensive intervention and one that helps motivate men to be physically active outside of the structured, small-group sessions. PMID:23918885

  5. Activated factor XI increases the procoagulant activity of the extrinsic pathway by inactivating tissue factor pathway inhibitor

    PubMed Central

    Tucker, Erik I.; Matafonov, Anton; Cheng, Qiufang; Zientek, Keith D.; Gailani, Dave; Gruber, András; McCarty, Owen J. T.

    2015-01-01

    Activation of coagulation factor XI (FXI) may play a role in hemostasis. The primary substrate of activated FXI (FXIa) is FIX, leading to FX activation (FXa) and thrombin generation. However, recent studies suggest the hemostatic role of FXI may not be restricted to the activation of FIX. We explored whether FXI could interact with and inhibit the activity of tissue factor pathway inhibitor (TFPI). TFPI is an essential reversible inhibitor of activated factor X (FXa) and also inhibits the FVIIa-TF complex. We found that FXIa neutralized both endothelium- and platelet-derived TFPI by cleaving the protein between the Kunitz (K) 1 and K2 domains (Lys86/Thr87) and at the active sites of the K2 (Arg107/Gly108) and K3 (Arg199/Ala200) domains. Addition of FXIa to plasma was able to reverse the ability of TFPI to prolong TF-initiated clotting times in FXI- or FIX-deficient plasma, as well as FXa-initiated clotting times in FX-deficient plasma. Treatment of cultured endothelial cells with FXIa increased the generation of FXa and promoted TF-dependent fibrin formation in recalcified plasma. Together, these results suggest that the hemostatic role of FXIa may be attributed not only to activation of FIX but also to promoting the extrinsic pathway of thrombin generation through inactivation of TFPI. PMID:25587039

  6. Activated factor XI increases the procoagulant activity of the extrinsic pathway by inactivating tissue factor pathway inhibitor.

    PubMed

    Puy, Cristina; Tucker, Erik I; Matafonov, Anton; Cheng, Qiufang; Zientek, Keith D; Gailani, Dave; Gruber, András; McCarty, Owen J T

    2015-02-26

    Activation of coagulation factor XI (FXI) may play a role in hemostasis. The primary substrate of activated FXI (FXIa) is FIX, leading to FX activation (FXa) and thrombin generation. However, recent studies suggest the hemostatic role of FXI may not be restricted to the activation of FIX. We explored whether FXI could interact with and inhibit the activity of tissue factor pathway inhibitor (TFPI). TFPI is an essential reversible inhibitor of activated factor X (FXa) and also inhibits the FVIIa-TF complex. We found that FXIa neutralized both endothelium- and platelet-derived TFPI by cleaving the protein between the Kunitz (K) 1 and K2 domains (Lys86/Thr87) and at the active sites of the K2 (Arg107/Gly108) and K3 (Arg199/Ala200) domains. Addition of FXIa to plasma was able to reverse the ability of TFPI to prolong TF-initiated clotting times in FXI- or FIX-deficient plasma, as well as FXa-initiated clotting times in FX-deficient plasma. Treatment of cultured endothelial cells with FXIa increased the generation of FXa and promoted TF-dependent fibrin formation in recalcified plasma. Together, these results suggest that the hemostatic role of FXIa may be attributed not only to activation of FIX but also to promoting the extrinsic pathway of thrombin generation through inactivation of TFPI. PMID:25587039

  7. Alkalosis and Dialytic Clearance of Phosphate Increases Phosphatase Activity: A Hidden Consequence of Hemodialysis

    PubMed Central

    Villa-Bellosta, Ricardo; González-Parra, Emilio; Egido, Jesús

    2016-01-01

    Background Extracellular pyrophosphate is a potent endogenous inhibitor of vascular calcification, which is degraded by alkaline phosphatase (ALP) and generated by hydrolysis of ATP via ectonucleotide pyrophosphatase/phosphodiesterase 1 (eNPP1). ALP activity (as routinely measured in clinical practice) represents the maximal activity (in ideal conditions), but not the real activity (in normal or physiological conditions). For the first time, the present study investigated extracellular pyrophosphate metabolism during hemodialysis sessions (including its synthesis via eNPP1 and its degradation via ALP) in physiological conditions. Methods and Findings 45 patients in hemodialysis were studied. Physiological ALP activity represents only 4–6% of clinical activity. ALP activity increased post-hemodialysis by 2% under ideal conditions (87.4 ± 3.3 IU/L vs. 89.3 ± 3.6 IU/L) and 48% under physiological conditions (3.5 ± 0.2 IU/L vs. 5.2 ± 0.2 IU/L). Pyrophosphate synthesis by ATP hydrolysis remained unaltered post-hemodialysis. Post-hemodialysis plasma pH (7.45 ± 0.02) significantly increased compared with the pre-dialysis pH (7.26 ± 0.02). The slight variation in pH (~0.2 units) induced a significant increase in ALP activity (9%). Addition of phosphate in post-hemodialysis plasma significantly decreased ALP activity, although this effect was not observed with the addition of urea. Reduction in phosphate levels and increment in pH were significantly associated with an increase in physiological ALP activity post-hemodialysis. A decrease in plasma pyrophosphate levels (3.3 ± 0.3 μmol/L vs. 1.9 ± 0.1 μmol/L) and pyrophosphate/ATP ratio (1.9 ± 0.2 vs. 1.4 ± 0.1) post-hemodialysis was also observed. Conclusion Extraction of uremic toxins, primarily phosphate and hydrogen ions, dramatically increases the ALP activity under physiological conditions. This hitherto unknown consequence of hemodialysis suggests a reinterpretation of the clinical value of this parameter

  8. Aquaporin 5 increases keratinocyte-derived chemokine expression and NF-κB activity through ERK activation.

    PubMed

    Sakamoto, Yuima; Hisatsune, Akinori; Katsuki, Hiroshi; Horie, Ichiro; Isohama, Yoichiro

    2014-06-13

    Aquaporin-5 (AQP5) is a water-selective channel protein that is expressed in submucosal glands and alveolar epithelial cells in the lungs. Recent studies have revealed that AQPs regulate not only water metabolism, but also some cellular functions such as cell growth and migration. Here, we report the role of AQP5 in inflammatory responses. In MLE-12 cells, knockdown of AQP5 using siRNA (10-50 nM) attenuated TNF-α-induced expression of keratinocyte chemoattractant (KC) mRNA and protein. Conversely, in NIH-3T3 cells, overexpression of AQP5 increased KC expression, NF-κB activation, and ERK phosphorylation. The AQP5-induced increase of KC expression was diminished by treatment with ERK inhibitors. Taken together, we propose a new function of AQP5 as an inflammatory signal potentiator, which may be mediated by increased activation of ERK and NF-κB. PMID:24747567

  9. covR Mediated Antibiofilm Activity of 3-Furancarboxaldehyde Increases the Virulence of Group A Streptococcus

    PubMed Central

    Ashwinkumar Subramenium, Ganapathy; Viszwapriya, Dharmaprakash; Iyer, Prasanth Mani; Balamurugan, Krishnaswamy; Karutha Pandian, Shunmugiah

    2015-01-01

    Background Group A streptococcus (GAS, Streptococcus pyogenes), a multi-virulent, exclusive human pathogen responsible for various invasive and non-invasive diseases possesses biofilm forming phenomenon as one of its pathogenic armaments. Recently, antibiofilm agents have gained prime importance, since inhibiting the biofilm formation is expected to reduce development of antibiotic resistance and increase their susceptibility to the host immune cells. Principal Findings The current study demonstrates the antibiofilm activity of 3Furancarboxaldehyde (3FCA), a floral honey derived compound, against GAS biofilm, which was divulged using crystal violet assay, light microscopy, and confocal laser scanning microscopy. The report is extended to study its effect on various aspects of GAS (morphology, virulence, aggregation) at its minimal biofilm inhibitory concentration (132μg/ml). 3FCA was found to alter the growth pattern of GAS in solid and liquid medium and increased the rate of auto-aggregation. Electron microscopy unveiled the increase in extra polymeric substances around cell. Gene expression studies showed down-regulation of covR gene, which is speculated to be the prime target for the antibiofilm activity. Increased hyaluronic acid production and down regulation of srtB gene is attributed to the enhanced rate of auto-aggregation. The virulence genes (srv, mga, luxS and hasA) were also found to be over expressed, which was manifested with the increased susceptibility of the model organism Caenorhabditis elegans to 3FCA treated GAS. The toxicity of 3FCA was ruled out with no adverse effect on C. elegans. Significance Though 3FCA possess antibiofilm activity against GAS, it was also found to increase the virulence of GAS. This study demonstrates that, covR mediated antibiofilm activity may increase the virulence of GAS. This also emphasizes the importance to analyse the acclimatization response and virulence of the pathogen in the presence of antibiofilm compounds

  10. Leptin differentially increases sympathetic nerve activity and its baroreflex regulation in female rats: role of oestrogen.

    PubMed

    Shi, Zhigang; Brooks, Virginia L

    2015-04-01

    Obesity and hypertension are commonly associated, and activation of the sympathetic nervous system is considered to be a major contributor, at least in part due to the central actions of leptin. However, while leptin increases sympathetic nerve activity (SNA) in males, whether leptin is equally effective in females is unknown. Here, we show that intracerebroventricular (i.c.v.) leptin increases lumbar (LSNA) and renal (RSNA) SNA and baroreflex control of LSNA and RSNA in α-chloralose anaesthetized female rats, but only during pro-oestrus. In contrast, i.c.v. leptin increased basal and baroreflex control of splanchnic SNA (SSNA) and heart rate (HR) in rats in both the pro-oestrus and dioestrus states. The effects of leptin on basal LSNA, RSNA, SSNA and HR were similar in males and pro-oestrus females; however, i.c.v. leptin increased mean arterial pressure (MAP) only in males. Leptin did not alter LSNA or HR in ovariectomized rats, but its effects were normalized with 4 days of oestrogen treatment. Bilateral nanoinjection of SHU9119 into the paraventricular nucleus of the hypothalamus (PVN), to block α-melanocyte-stimulating hormone (α-MSH) type 3 and 4 receptors, decreased LSNA in leptin-treated pro-oestrus but not dioestrus rats. Unlike leptin, i.c.v. insulin infusion increased basal and baroreflex control of LSNA and HR similarly in pro-oestrus and dioestrus rats; these responses did not differ from those in male rats. We conclude that, in female rats, leptin's stimulatory effects on SNA are differentially enhanced by oestrogen, at least in part via an increase in α-MSH activity in the PVN. These data further suggest that the actions of leptin and insulin to increase the activity of various sympathetic nerves occur via different neuronal pathways or cellular mechanisms. These results may explain the poor correlation in females of SNA with adiposity, or of MAP with leptin. PMID:25398524

  11. Paradoxical control properties of enzymes within pathways: can activation cause an enzyme to have increased control?

    PubMed Central

    Kholodenko, B N; Brown, G C

    1996-01-01

    It is widely assumed that within a metabolic pathway inhibition of an enzyme causes the control exerted by that enzyme over the flux through its own reaction to increase, whereas activation causes its control to decrease. This assumption forms the basis of a number of experimental methods. For a pathway conceptually divided into two enzyme groups connected via a single metabolite we have derived a general condition under which this assumption is false, and thus the pathway shows paradoxical control behaviour, i.e. increased control with activation and decreased control with inhibition of an enzyme or group of enzymes. Paradoxical control behaviour occurs widely when enzyme activity is altered by changing Km (if an enzyme is already close to saturation by its substrate), but may also occur with changes in Vmax. when the elasticity to the linking metabolite increases with its concentration (as in some cases of sigmoidal and exponential kinetics or for reactions catalysed by isoenzymes). These findings suggest that enzymes with sigmoidal kinetics may have low control in the absence of activation, but may gain control with activation, and thus have beneficial regulatory properties. PMID:8615766

  12. Greater electroencephalographic coherence between left and right temporal lobe structures during increased geomagnetic activity.

    PubMed

    Saroka, Kevin S; Caswell, Joseph M; Lapointe, Andrew; Persinger, Michael A

    2014-02-01

    Interhemispheric coherence for 19 channel EEG activity collected over a three year period from 184 men and women who relaxed in a quiet, darkened chamber showed significant increased coherence between caudal temporal regions for the 11 Hz frequency band during increased (>∼8 nT) global geomagnetic activity at the time of measurement. Detailed analyses from source-localization indicated that a likely origin was the parahippocampal regions whose net differences at 10, 11 and 12 Hz intervals were significantly correlated with geomagnetic activity. Analyses of residuals to obtain a "purer" measure of parahippocampal contributions indicated that interhemispheric temporal lobe coherence across unit increments between 1 and 40 Hz revealed the most statistically significant peaks at 7.5 Hz and 19.5 Hz. These weak but reliable correlations between global geomagnetic activity and the degree of inter-temporal lobe coherence for normal people relaxing in a dark, quiet area are consistent with the results of multiple studies indicating that intrusive experiences such as "presences" or "hallucinations" are more frequent when global geomagnetic activity increases above ∼15-20 nT. PMID:24287380

  13. Cocaine Increases Dopaminergic Neuron and Motor Activity via Midbrain α1 Adrenergic Signaling

    PubMed Central

    Goertz, Richard Brandon; Wanat, Matthew J; Gomez, Jorge A; Brown, Zeliene J; Phillips, Paul EM; Paladini, Carlos A

    2015-01-01

    Cocaine reinforcement is mediated by increased extracellular dopamine levels in the forebrain. This neurochemical effect was thought to require inhibition of dopamine reuptake, but cocaine is still reinforcing even in the absence of the dopamine transporter. Here, we demonstrate that the rapid elevation in dopamine levels and motor activity elicited by cocaine involves α1 receptor activation within the ventral midbrain. Activation of α1 receptors increases dopaminergic neuron burst firing by decreasing the calcium-activated potassium channel current (SK), as well as elevates dopaminergic neuron pacemaker firing through modulation of both SK and the hyperpolarization-activated cation currents (Ih). Furthermore, we found that cocaine increases both the pacemaker and burst-firing frequency of rat ventral-midbrain dopaminergic neurons through an α1 adrenergic receptor-dependent mechanism within the ventral tegmental area and substantia nigra pars compacta. These results demonstrate the mechanism underlying the critical role of α1 adrenergic receptors in the regulation of dopamine neurotransmission and behavior by cocaine. PMID:25374094

  14. Nandrolone reduces activation of Notch signaling in denervated muscle associated with increased Numb expression

    SciTech Connect

    Liu, Xin-Hua; Yao, Shen; Qiao, Rui-Fang; Levine, Alice C.; Kirschenbaum, Alexander; Pan, Jiangping; Wu, Yong; Qin, Weiping; Bauman, William A.; Cardozo, Christopher P.

    2011-10-14

    Highlights: {yields} Nerve transection increased Notch signaling in paralyzed muscle. {yields} Nandrolone prevented denervation-induced Notch signaling. {yields} Nandrolone induced the expression of an inhibitor of the Notch signaling, Numb. {yields} Reduction of denervation-induced Notch signaling by nandrolone is likely through upregulation of Numb. -- Abstract: Nandrolone, an anabolic steroid, slows denervation-atrophy in rat muscle. The molecular mechanisms responsible for this effect are not well understood. Androgens and anabolic steroids activate Notch signaling in animal models of aging and thereby mitigate sarcopenia. To explore the molecular mechanisms by which nandrolone prevents denervation-atrophy, we investigated the effects of nandrolone on Notch signaling in denervated rat gastrocnemius muscle. Denervation significantly increased Notch activity reflected by elevated levels of nuclear Notch intracellular domain (NICD) and expression of Hey1 (a Notch target gene). Activation was greatest at 7 and 35 days after denervation but remained present at 56 days after denervation. Activation of Notch in denervated muscle was prevented by nandrolone associated with upregulated expression of Numb mRNA and protein. These data demonstrate that denervation activates Notch signaling, and that nandrolone abrogates this response associated with increased expression of Numb, suggesting a potential mechanism by which nandrolone reduces denervation-atrophy.

  15. Reminiscence Activity and Increased Communication Interaction among Cognitively Disabled Elderly Women.

    ERIC Educational Resources Information Center

    Krupar, Karen R.; Smith, N. Richmond

    Designed as the first phase of a larger project to explore the relationships between the possible impact of reminiscence on memory deterioration in elderly women confined to nursing home environments, a study demonstrated that reminiscence activity is positively correlated with increases in communication interactions. Women were chosen as the…

  16. DIETARY PROTEIN AND LACTOSE INCREASE TRANSLATION INITIATION FACTOR ACTIVATION AND TISSUE PROTEIN SYNTHESIS IN NEONATAL PIGS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Protein synthesis and eukaryotic initiation factor (eIF) activation are increased in muscle and liver of pigs parenterally infused with amino acids and insulin. To examine the effects of enteral protein and carbohydrate on protein synthesis, pigs (n = 42, 1.7 kg body wt) were fed isocaloric milk die...

  17. An increase of Optical Activity in the Quasar 3C454.3

    NASA Astrophysics Data System (ADS)

    Jorstad, Svetlana

    2016-06-01

    The quasar 3C454.3 shows an increase of the optical activity during the last three nights. According to our observations at the Perkins telescope of the Lowell Observatory (Flagstaff, AZ) the brightness of the source on June 10 (JD 2457549.8770) in R band was 15.817+-0.018 with a of polarization of 2.27+-0.39%.

  18. Cyclic strain increases protease-activated receptor-1 expression in vascular smooth muscle cells

    NASA Technical Reports Server (NTRS)

    Nguyen, K. T.; Frye, S. R.; Eskin, S. G.; Patterson, C.; Runge, M. S.; McIntire, L. V.

    2001-01-01

    Cyclic strain regulates many vascular smooth muscle cell (VSMC) functions through changing gene expression. This study investigated the effects of cyclic strain on protease-activated receptor-1 (PAR-1) expression in VSMCs and the possible signaling pathways involved, on the basis of the hypothesis that cyclic strain would enhance PAR-1 expression, reflecting increased thrombin activity. Uniaxial cyclic strain (1 Hz, 20%) of cells cultured on elastic membranes induced a 2-fold increase in both PAR-1 mRNA and protein levels. Functional activity of PAR-1, as assessed by cell proliferation in response to thrombin, was also increased by cyclic strain. In addition, treatment of cells with antioxidants or an NADPH oxidase inhibitor blocked strain-induced PAR-1 expression. Preincubation of cells with protein kinase inhibitors (staurosporine or Ro 31-8220) enhanced strain-increased PAR-1 expression, whereas inhibitors of NO synthase, tyrosine kinase, and mitogen-activated protein kinases had no effect. Cyclic strain in the presence of basic fibroblast growth factor induced PAR-1 mRNA levels beyond the effect of cyclic strain alone, whereas no additive effect was observed between cyclic strain and platelet-derived growth factor-AB. Our findings that cyclic strain upregulates PAR-1 mRNA expression but that shear stress downregulates this gene in VSMCs provide an opportunity to elucidate signaling differences by which VSMCs respond to different mechanical forces.

  19. Text Messaging as a Tool to Increase Physical Activity in College Students

    ERIC Educational Resources Information Center

    Muñoz, Laura R.; La France, Kevin; Dominguez, Daniel; Goei, Kathleen; Herbers, Sharon; Gunter, M. Danielle; Fike, David; Carleton, William; Etnyre, Annette; Richardson, Cynthia; Allwein, David; Rauschhuber, Maureen; Norgan, Gary; Moore, Renée; Marquise, Lisa; Jones, Mary Elaine

    2014-01-01

    The purpose of this study was to assess the effectiveness of text messaging with pedometer intervention for increasing physical activity of college students. Using a two-group prospective randomized intervention-based design, the researchers gave 201 college students pedometers and divided them into intervention and control groups. The…

  20. NFAT-133 increases glucose uptake in L6 myotubes by activating AMPK pathway.

    PubMed

    Thakkar, Chandni S; Kate, Abhijeet S; Desai, Dattatraya C; Ghosh, Asit Ranjan; Kulkarni-Almeida, Asha A

    2015-12-15

    NFAT-133 is an aromatic compound with cinammyl alcohol moiety, isolated from streptomycetes strain PM0324667. We have earlier reported that NFAT-133 increases insulin stimulated glucose uptake in L6 myotubes using a PPARγ independent mechanism and reduces plasma or blood glucose levels in diabetic mice. Here we investigated the effects of NFAT-133 on cellular signaling pathways leading to glucose uptake in L6 myotubes. Our studies demonstrate that NFAT-133 increases glucose uptake in a dose- and time-dependent manner independent of the effects of insulin. Treatment with Akti-1/2, wortmannin and increasing concentrations of insulin had no effect on NFAT-133 mediated glucose uptake. NFAT-133 induced glucose uptake is completely mitigated by Compound C, an AMPK inhibitor. Further, the kinases upstream of AMPK activation namely; LKB-1 and CAMKKβ are not involved in NFAT-133 mediated AMPK activation nor does the compound NFAT-133 have any effect on AMPK enzyme activity. Further analysis confirmed that NFAT-133 indirectly activates AMPK by reducing the mitochondrial membrane potential and increasing the ratio of AMP:ATP. PMID:26546724

  1. Oxidized LDL levels are increased in HIV infection and may drive monocyte activation

    PubMed Central

    Zidar, David A.; Juchnowski, Steven; Ferrari, Brian; Clagett, Brian; Pilch-Cooper, Heather A.; Rose, Shawn; Rodriguez, Benigno; McComsey, Grace A.; Sieg, Scott F.; Mehta, Nehal N.; Lederman, Michael M.; Funderburg, Nicholas T.

    2015-01-01

    Background Human immunodeficiency virus (HIV) infection is associated with increased cardiovascular risk, and this risk correlates with markers of monocyte activation. We have shown that HIV is associated with a prothrombotic monocyte phenotype, which can be partially mitigated by statin therapy. We therefore explored the relationship between oxidized LDL particles and monocyte activation. Methods We performed phenotypic analysis of monocytes using flow cytometry on fresh whole blood in 54 patients with HIV and 24 controls without HIV. Plasma levels of oxLDL, soluble CD14, IL-6, soluble CD163 were measured by ELISA. In vitro experiments were performed using flow cytometry. Results Plasma levels of oxLDL were significantly increased in HIV-infection compared to controls (60.1 units vs 32.1 units, p<0.001). Monocyte expression of the oxLDL receptors, CD36 and Toll-like receptor 4, were also increased in HIV. OxLDL levels correlated with markers of monocyte activation, including soluble CD14, TF expression on inflammatory monocytes, and CD36. In vitro, stimulation with oxLDL, but not to LDL, resulted in expansion of inflammatory monocytes and increased monocyte expression of TF, recapitulating the monocyte profile we find in HIV disease. Conclusions OxLDL may contribute to monocyte activation and further study in the context of HIV disease is warranted. PMID:25647528

  2. Decreasing Sports Activity with Increasing Age? Findings from a 20-Year Longitudinal and Cohort Sequence Analysis

    ERIC Educational Resources Information Center

    Breuer, Christoph; Wicker, Pamela

    2009-01-01

    According to cross-sectional studies in sport science literature, decreasing sports activity with increasing age is generally assumed. In this paper, the validity of this assumption is checked by applying more effective methods of analysis, such as longitudinal and cohort sequence analyses. With the help of 20 years' worth of data records from the…

  3. Planar fuel cell utilizing nail current collectors for increased active surface area

    DOEpatents

    George, Thomas J.; Meacham, G. B. Kirby

    2002-03-26

    A plurality of nail current collector members are useful in the gas flow passages of an electrochemical device to optimize the active surfaces of the device and to provide structural support. In addition, the thicknesses of cathode and anode layers within the electrochemical device are varied according to current flow through the device to reduce resistance and increase operating efficiency.

  4. Integrated Health and Physical Education Program to Reduce Media Use and Increase Physical Activity in Youth

    ERIC Educational Resources Information Center

    Clocksin, Brian D.; Wattson, Doris L.; Williams, Daniel P.; Randsell, Lynda

    2009-01-01

    The purpose of this project was to compare an integrated health and physical education curriculum, focused on reducing media use and on increasing physical activity in middle school adolescents, to traditional and nonintegrated health and physical education curricula. Two middle schools' health and physical education classes were assigned to an…

  5. Increased skeletal VEGF enhances β-catenin activity and results in excessively ossified bones

    PubMed Central

    Maes, Christa; Goossens, Steven; Bartunkova, Sonia; Drogat, Benjamin; Coenegrachts, Lieve; Stockmans, Ingrid; Moermans, Karen; Nyabi, Omar; Haigh, Katharina; Naessens, Michael; Haenebalcke, Lieven; Tuckermann, Jan P; Tjwa, Marc; Carmeliet, Peter; Mandic, Vice; David, Jean-Pierre; Behrens, Axel; Nagy, Andras; Carmeliet, Geert; Haigh, Jody J

    2010-01-01

    Vascular endothelial growth factor (VEGF) and β-catenin both act broadly in embryogenesis and adulthood, including in the skeletal and vascular systems. Increased or deregulated activity of these molecules has been linked to cancer and bone-related pathologies. By using novel mouse models to locally increase VEGF levels in the skeleton, we found that embryonic VEGF over-expression in osteo-chondroprogenitors and their progeny largely pheno-copied constitutive β-catenin activation. Adult induction of VEGF in these cell populations dramatically increased bone mass, associated with aberrant vascularization, bone marrow fibrosis and haematological anomalies. Genetic and pharmacological interventions showed that VEGF increased bone mass through a VEGF receptor 2- and phosphatidyl inositol 3-kinase-mediated pathway inducing β-catenin transcriptional activity in endothelial and osteoblastic cells, likely through modulation of glycogen synthase kinase 3-β phosphorylation. These insights into the actions of VEGF in the bone and marrow environment underscore its power as pleiotropic bone anabolic agent but also warn for caution in its therapeutic use. Moreover, the finding that VEGF can modulate β-catenin activity may have widespread physiological and clinical ramifications. PMID:20010698

  6. The effect of increase in baggage weight on elderly women's lower extremity muscle activation during gait.

    PubMed

    Kim, Seong-Gil; Nam, Chan-Woo; Yong, Min-Sik

    2014-01-01

    The aim of the present study was to examine the effect of increased baggage weight on the muscle activation of elderly women's lower extremities during gait. A total of 24 elderly women who were residing in communities in Daegu, South Korea aged 79.6±6.2, 149.7±7.0cm in height, and 53.5±7.2kg in weight participated in this study. The muscle activation of each muscle was measured three times at 2kg, 3kg, and 4kg of baggage weight while the subjects were conducting treadmill walking wearing backpacks. Electrodes were placed on four muscles: the quadriceps muscle (rectus femoris), the hamstring muscle (semitendinosus), the tibialis anterior muscle, and the soleus muscle. The results show that the rates of increase in muscle activation in the tibialis anterior and soleus muscles according to baggage weight increase were higher than those in the quadriceps and hamstring muscles (<0.05). These results indicate that the heavier weight loads increase the activation of muscles that control the ankle joints causing muscle fatigue. Moreover, a decrease in balance ability through muscle fatigue can be a risk factor for falls. Thus, elderly people should be instructed not to carry heavy objects. PMID:25179442

  7. Peers Increase Adolescent Risk Taking by Enhancing Activity in the Brain's Reward Circuitry

    ERIC Educational Resources Information Center

    Chein, Jason; Albert, Dustin; O'Brien, Lia; Uckert, Kaitlyn; Steinberg, Laurence

    2011-01-01

    The presence of peers increases risk taking among adolescents but not adults. We posited that the presence of peers may promote adolescent risk taking by sensitizing brain regions associated with the anticipation of potential rewards. Using fMRI, we measured brain activity in adolescents, young adults, and adults as they made decisions in a…

  8. Increasing Student Involvement in Self-Governance Activities: A Delphi Approach.

    ERIC Educational Resources Information Center

    Miles, Jennifer M.; Miller, Michael T.

    This study used a Delphi survey to examine what undergraduate student government leaders think about increasing student involvement in self-governance activities. Twenty-students from geographically diverse institutions of higher education participated in the three rounds of the Delphi study. They generated a total of 56 different strategies and…

  9. 78 FR 75905 - Credit for Increasing Research Activities: Intra-Group Gross Receipts

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-13

    ... similar provisions of the Code. See, e.g., Prop. Reg. Sec. 1.199-1, 70 FR 67220, 67236 (November 4, 2005...; ] DEPARTMENT OF TREASURY Internal Revenue Service 26 CFR Part 1 RIN 1545-BE14 Credit for Increasing Research Activities: Intra-Group Gross Receipts AGENCY: Internal Revenue Service (IRS), Treasury. ACTION: Notice...

  10. Increasing Children's Physical Activity: Individual, Social, and Environmental Factors Associated with Walking to and from School

    ERIC Educational Resources Information Center

    Trapp, Georgina S. A.; Giles-Corti, Billie; Christian, Hayley E.; Bulsara, Max; Timperio, Anna F.; McCormack, Gavin R.; Villaneuva, Karen P.

    2012-01-01

    Background. Efforts to increase the prevalence of children's active school transport require evidence to inform the development of comprehensive interventions. This study used a multilevel ecological framework to investigate individual, social, and environmental factors associated with walking to and from school among elementary school-aged…

  11. Renal sympathetic nerve activity is increased in monosodium glutamate induced hyperadipose rats.

    PubMed

    da Silva Mattos, Alexandro Márcio; Xavier, Carlos Henrique; Karlen-Amarante, Marlusa; da Cunha, Natália Veronez; Fontes, Marco Antonio Peliky; Martins-Pinge, Marli Cardoso

    2012-08-01

    The literature suggests that both obesity and hypertension are associated with increased sympathetic nerve activity. In the present study we evaluated the renal sympathetic nerve activity (RSNA), mean arterial pressure (MAP) and heart rate (HR) in hyperadipose rats induced by neonatal administration of monosodium glutamate (MSG). Neonatal Wistar male rats were injected with MSG (4 mg/g body weight ID) or equimolar saline (control) for 5 days. At 90th day, all rats were anesthetized (urethane 1.4 g/kg) and prepared for MAP, HR and renal sympathetic nerve activity recordings. The anesthetized MSG rats presented baseline hypertension and increased baseline RSNA compared with control. Our results suggest the involvement of the renal sympathetic nervous system in the physiopathology of the MSG obesity. PMID:22705582

  12. Successful face recognition is associated with increased prefrontal cortex activation in autism spectrum disorder.

    PubMed

    Herrington, John D; Riley, Meghan E; Grupe, Daniel W; Schultz, Robert T

    2015-04-01

    This study examines whether deficits in visual information processing in autism-spectrum disorder (ASD) can be offset by the recruitment of brain structures involved in selective attention. During functional MRI, 12 children with ASD and 19 control participants completed a selective attention one-back task in which images of faces and houses were superimposed. When attending to faces, the ASD group showed increased activation relative to control participants within multiple prefrontal cortex areas, including dorsolateral prefrontal cortex (DLPFC). DLPFC activation in ASD was associated with increased response times for faces. These data suggest that prefrontal cortex activation may represent a compensatory mechanism for diminished visual information processing abilities in ASD. PMID:25234479

  13. Increasing girls’ physical activity during an organised youth sport basketball program: a randomised controlled trial protocol

    PubMed Central

    2014-01-01

    Background Participation in organised youth sports (OYS) has been recommended as an opportunity to increase young peoples’ moderate-to-vigorous physical activity (MVPA) levels. Participants, however, spend a considerable proportion of time during OYS inactive. The purpose of this study, therefore, was to investigate whether coaches who attended coach education sessions (where education on increasing MVPA and decreasing inactivity during training was delivered) can increase players’ MVPA during training sessions over a 5-day basketball program compared to coaches who did not receive coach education sessions. Methods/design A convenience sample of 80 female players and 8 coaches were recruited into the UWS School Holiday Basketball Program in Greater Western Sydney, Australia. A two-arm, parallel-group randomised controlled trial was employed to investigate whether coaches who attended 2 coach education sessions (compared with a no-treatment control) can increase their players’ MVPA during training sessions over a 5-day basketball program. Objectively measured physical activity, directly observed lesson context and leader behaviour, player motivation, players’ perceived autonomy support, and coaching information (regarding training session planning, estimations on player physical activity and lesson context during training, perceived ability to modify training sessions, perceived importance of physical activity during training, intention to increase physical activity/reduce inactivity, and likelihood of increasing physical activity/reducing inactivity) were assessed at baseline (day 1) and at follow-up (day 5). Linear mixed models will be used to analyse between arm differences in changes from baseline to follow-up on all outcomes. Discussion The current trial protocol describes, to our knowledge, the first trial conducted in an OYS context to investigate the efficacy of an intervention, relative to a control, in increasing MVPA. This study’s findings will

  14. Lumbricus terrestris L. activity increases the availability of metals and their accumulation in maize and barley.

    PubMed

    Ruiz, E; Alonso-Azcárate, J; Rodríguez, L

    2011-03-01

    The effect of the earthworm Lumbricus terrestris L. on metal availability in two mining soils was assessed by means of chemical extraction methods and a pot experiment using crop plants. Results from single and sequential extractions showed that L. terrestris had a slight effect on metal fractionation in the studied soils: only metals bound to the soil organic matter were significantly increased in some cases. However, we found that L. terrestris significantly increased root, shoot and total Pb and Zn concentrations in maize and barley for the soil with the highest concentrations of total and available metals. Specifically, shoot Pb concentration was increased by a factor of 7.5 and 3.9 for maize and barley, respectively, while shoot Zn concentration was increased by a factor of 3.7 and 1.7 for maize and barley, respectively. Our results demonstrated that earthworm activity increases the bioavailability of metals in soils. PMID:21190761

  15. The TMS Map Scales with Increased Stimulation Intensity and Muscle Activation.

    PubMed

    van de Ruit, Mark; Grey, Michael J

    2016-01-01

    One way to study cortical organisation, or its reorganisation, is to use transcranial magnetic stimulation (TMS) to construct a map of corticospinal excitability. TMS maps are reported to be acquired with a wide variety of stimulation intensities and levels of muscle activation. Whilst MEPs are known to increase both with stimulation intensity and muscle activation, it remains to be established what the effect of these factors is on the map's centre of gravity (COG), area, volume and shape. Therefore, the objective of this study was to systematically examine the effect of stimulation intensity and muscle activation on these four key map outcome measures. In a first experiment, maps were acquired with a stimulation intensity of 110, 120 and 130% of resting threshold. In a second experiment, maps were acquired at rest and at 5, 10, 20 and 40% of maximum voluntary contraction. Map area and map volume increased with both stimulation intensity (P < 0.01) and muscle activation (P < 0.01). Neither the COG nor the map shape changed with either stimulation intensity or muscle activation (P > 0.09 in all cases). This result indicates the map simply scales with stimulation intensity and muscle activation. PMID:26337508

  16. Microbial Translocation Is Associated with Increased Monocyte Activation and Dementia in AIDS Patients

    PubMed Central

    Ancuta, Petronela; Kamat, Anupa; Kunstman, Kevin J.; Kim, Eun-Young; Autissier, Patrick; Wurcel, Alysse; Zaman, Tauheed; Stone, David; Mefford, Megan; Morgello, Susan; Singer, Elyse J.; Wolinsky, Steven M.; Gabuzda, Dana

    2008-01-01

    Elevated plasma lipopolysaccharide (LPS), an indicator of microbial translocation from the gut, is a likely cause of systemic immune activation in chronic HIV infection. LPS induces monocyte activation and trafficking into brain, which are key mechanisms in the pathogenesis of HIV-associated dementia (HAD). To determine whether high LPS levels are associated with increased monocyte activation and HAD, we obtained peripheral blood samples from AIDS patients and examined plasma LPS by Limulus amebocyte lysate (LAL) assay, peripheral blood monocytes by FACS, and soluble markers of monocyte activation by ELISA. Purified monocytes were isolated by FACS sorting, and HIV DNA and RNA levels were quantified by real time PCR. Circulating monocytes expressed high levels of the activation markers CD69 and HLA-DR, and harbored low levels of HIV compared to CD4+ T-cells. High plasma LPS levels were associated with increased plasma sCD14 and LPS-binding protein (LBP) levels, and low endotoxin core antibody levels. LPS levels were higher in HAD patients compared to control groups, and were associated with HAD independently of plasma viral load and CD4 counts. LPS levels were higher in AIDS patients using intravenous heroin and/or ethanol, or with Hepatitis C virus (HCV) co-infection, compared to control groups. These results suggest a role for elevated LPS levels in driving monocyte activation in AIDS, thereby contributing to the pathogenesis of HAD, and provide evidence that cofactors linked to substance abuse and HCV co-infection influence these processes. PMID:18575590

  17. Superoxide dismutase and catalase conjugated to polyethylene glycol increases endothelial enzyme activity and oxidant resistance

    SciTech Connect

    Beckman, J.S.; Minor, R.L. Jr.; White, C.W.; Repine, J.E.; Rosen, G.M.; Freeman, B.A.

    1988-05-15

    Covalent conjugation of superoxide dismutase and catalase with polyethylene glycol (PEG) increases the circulatory half-lives of these enzymes from <10 min to 40 h, reduced immunogenicity, and decreases sensitivity to proteolysis. Because PEG has surface active properties and can induce cell fusion, the authors hypothesized that PEG conjugation could enhance cell binding and association of normally membrane-impermeable enzymes. Incubation of cultured porcine aortic endothelial cells with /sup 125/I-PEG-catalase or /sup 125/I-PEG-superoxide dismutase produced a linear, concentration-dependent increase in cellular enzyme activity and radioactivity. Fluorescently labeled PEG-superoxide dismutase incubated with endothelial cells showed a vesicular localization. Mechanical injury to cell monolayers, which is known to stimulate endocytosis, further increased the uptake of fluorescent PEG-superoxide dismutase. Addition of PEG and PEG-conjugated enzymes perturbed the spin-label binding environment, indicative of producing an increase in plasma membrane fluidity. Thus, PEG conjugation to superoxide dismutase and catalase enhances cell association of these enzymes in a manner which increases cellular enzyme activities and provides prolonged protection from partially reduced oxygen species.

  18. Increasing total and biologically active chromium in wheat grain and spinach by spraying with chromium salts

    SciTech Connect

    Vicini, F.A.; Ellis, B.G.

    1981-06-01

    Recently, chromium has been shown to be necessary for glucose metabolism in man. But most plant species greatly restrict the uptake of Cr. This study was conducted to determine if both total and biologically active Cr could be increased in wheat grain or spinach by spraying the plants with either Cr/sub 2/(SO/sub 4/)/sub 3/ or Cr-EDTA. Concentrations of Cr in wheat grain were about doubled in a greenhouse experiment by spraying with either Cr source. Biologically active Cr (estimated by extraction with ethanol or NH/sub 4/OH) was increased from about 40 to greater than 50% of total Cr when wheat was sprayed with Cr salts. Total Cr in spinach leaves was increased by as much as 10-fold by spraying, with the sulfate source being more effective than the EDTA.

  19. TRPA1 activation by lidocaine in nerve terminals results in glutamate release increase

    SciTech Connect

    Piao, L.-H.; Fujita, Tsugumi; Jiang, C.-Y.; Liu Tao; Yue, H.-Y.; Nakatsuka, Terumasa; Kumamoto, Eiichi

    2009-02-20

    We examined the effects of local anesthetics lidocaine and procaine on glutamatergic spontaneous excitatory transmission in substantia gelatinosa (SG) neurons in adult rat spinal cord slices with whole-cell patch-clamp techniques. Bath-applied lidocaine (1-5 mM) dose-dependently and reversibly increased the frequency but not the amplitude of spontaneous excitatory postsynaptic current (sEPSC) in SG neurons. Lidocaine activity was unaffected by the Na{sup +}-channel blocker, tetrodotoxin, and the TRPV1 antagonist, capsazepine, but was inhibited by the TRP antagonist, ruthenium red. In the same neuron, the TRPA1 agonist, allyl isothiocyanate, and lidocaine both increased sEPSC frequency. In contrast, procaine did not produce presynaptic enhancement. These results indicate that lidocaine activates TRPA1 in nerve terminals presynaptic to SG neurons to increase the spontaneous release of L-glutamate.

  20. Alpha-Amylase Activity in Blood Increases after Pharmacological, But Not Psychological, Activation of the Adrenergic System

    PubMed Central

    Nater, Urs M.; La Marca, Roberto; Erni, Katja; Ehlert, Ulrike

    2015-01-01

    Background & Aim Alpha-amylase in both blood and saliva has been used as a diagnostic parameter. While studies examining alpha-amylase activity in saliva have shown that it is sensitive to physiological and psychological challenge of the adrenergic system, no challenge studies have attempted to elucidate the role of the adrenergic system in alpha-amylase activity in blood. We set out to examine the impact of psychological and pharmacological challenge on alpha-amylase in blood in two separate studies. Methods In study 1, healthy subjects were examined in a placebo-controlled, double-blind paradigm using yohimbine, an alpha2-adrenergic antagonist. In study 2, subjects were examined in a standardized rest-controlled psychosocial stress protocol. Alpha-amylase activity in blood was repeatedly measured in both studies. Results Results of study 1 showed that alpha-amylase in blood is subject to stronger increases after injection of yohimbine compared to placebo. In study 2, results showed that there was no significant effect of psychological stress compared to rest. Conclusions Alpha-amylase in blood increases after pharmacological activation of the adrenergic pathways suggesting that sympathetic receptors are responsible for these changes. Psychological stress, however, does not seem to have an impact on alpha-amylase in blood. Our findings provide insight into the mechanisms underlying activity changes in alpha-amylase in blood in healthy individuals. PMID:26110636

  1. Increased digitalis-like activity in human cerebrospinal fluid after expansion of the extracellular fluid volume

    SciTech Connect

    Halperin, J.A.; Martin, A.M.; Malave, S.

    1985-08-12

    The present study was designed to determine whether acute expansion of the extracellular fluid volume influenced the digitalis-like activity of human cerebrospinal fluid (CSF), previously described. Human CSF samples, drawn before and 30 minutes after the intravenous infusion of 1 liter of either saline or glucose solutions, were assayed for digitalis-like activity by inhibition of either the /sup 86/Rb/sup +/ uptake into human erythrocytes or by the activity of a purified Na/sup +/-K/sup +/ ATPase. The CSF inhibitory activity on both systems significantly increased after the infusion of sodium solutions but did not change after the infusion of glucose. These results indicate that the digitalis-like factor of human CSF might be involved in the regulation of the extracellular fluid volume and electrolyte content and thereby in some of the physiological responses to sodium loading. 31 references, 2 figures, 1 table.

  2. Mouse skin passage of Streptococcus pyogenes results in increased streptokinase expression and activity.

    PubMed

    Rezcallah, Myrna S; Boyle, Michael D P; Sledjeski, Darren D

    2004-02-01

    The plasminogen activator streptokinase has been proposed to be a key component of a complex mechanism that promotes skin invasion by Streptococcus pyogenes. This study was designed to compare ska gene message and protein levels in wild-type M1 serotype isolate 1881 and a more invasive variant recovered from the spleen of a lethally infected mouse. M1 isolates selected for invasiveness demonstrated enhanced levels of active plasminogen activator activity in culture. This effect was due to a combination of increased expression of the ska gene and decreased expression of the speB gene. The speB gene product, SpeB, was found to efficiently degrade streptokinase in vitro. PMID:14766914

  3. Decreases in Theta and Increases in High Frequency Activity Underlie Associative Memory Encoding

    PubMed Central

    Greenberg, Jeffrey A.; Burke, John F.; Haque, Rafi; Kahana, Michael J.; Zaghloul, Kareem A.

    2015-01-01

    Episodic memory encoding refers to the cognitive process by which items and their associated contexts are stored in memory. To investigate changes directly attributed to the formation of explicit associations, we examined oscillatory power captured through intracranial electroencephalography (iEEG) as 27 neurosurgical patients receiving subdural and depth electrodes for seizure monitoring participated in a paired associates memory task. We examined low (3–8 Hz) and high (45–95 Hz) frequency activity, and found that the successful formation of new associations was accompanied by broad decreases in low frequency activity and a posterior to anterior progression of increases in high frequency activity in the left hemisphere. These data suggest that the observed patterns of activity may reflect the neural mechanisms underlying the formation of novel item-item associations. PMID:25862266

  4. Nanocaged enzymes with enhanced catalytic activity and increased stability against protease digestion

    NASA Astrophysics Data System (ADS)

    Zhao, Zhao; Fu, Jinglin; Dhakal, Soma; Johnson-Buck, Alexander; Liu, Minghui; Zhang, Ting; Woodbury, Neal W.; Liu, Yan; Walter, Nils G.; Yan, Hao

    2016-02-01

    Cells routinely compartmentalize enzymes for enhanced efficiency of their metabolic pathways. Here we report a general approach to construct DNA nanocaged enzymes for enhancing catalytic activity and stability. Nanocaged enzymes are realized by self-assembly into DNA nanocages with well-controlled stoichiometry and architecture that enabled a systematic study of the impact of both encapsulation and proximal polyanionic surfaces on a set of common metabolic enzymes. Activity assays at both bulk and single-molecule levels demonstrate increased substrate turnover numbers for DNA nanocage-encapsulated enzymes. Unexpectedly, we observe a significant inverse correlation between the size of a protein and its activity enhancement. This effect is consistent with a model wherein distal polyanionic surfaces of the nanocage enhance the stability of active enzyme conformations through the action of a strongly bound hydration layer. We further show that DNA nanocages protect encapsulated enzymes against proteases, demonstrating their practical utility in functional biomaterials and biotechnology.

  5. Nanocaged enzymes with enhanced catalytic activity and increased stability against protease digestion

    PubMed Central

    Zhao, Zhao; Fu, Jinglin; Dhakal, Soma; Johnson-Buck, Alexander; Liu, Minghui; Zhang, Ting; Woodbury, Neal W.; Liu, Yan; Walter, Nils G.; Yan, Hao

    2016-01-01

    Cells routinely compartmentalize enzymes for enhanced efficiency of their metabolic pathways. Here we report a general approach to construct DNA nanocaged enzymes for enhancing catalytic activity and stability. Nanocaged enzymes are realized by self-assembly into DNA nanocages with well-controlled stoichiometry and architecture that enabled a systematic study of the impact of both encapsulation and proximal polyanionic surfaces on a set of common metabolic enzymes. Activity assays at both bulk and single-molecule levels demonstrate increased substrate turnover numbers for DNA nanocage-encapsulated enzymes. Unexpectedly, we observe a significant inverse correlation between the size of a protein and its activity enhancement. This effect is consistent with a model wherein distal polyanionic surfaces of the nanocage enhance the stability of active enzyme conformations through the action of a strongly bound hydration layer. We further show that DNA nanocages protect encapsulated enzymes against proteases, demonstrating their practical utility in functional biomaterials and biotechnology. PMID:26861509

  6. Increased Activity of Rhizosphere and Hyphosphere Enzymes under Elevated CO2 in a Loblolly Pine Stand

    NASA Astrophysics Data System (ADS)

    Meier, I.; Phillips, R.

    2012-12-01

    The stimulatory effect of elevated atmospheric CO2 under global climate change on forest productivity has been predicted to decrease over time as pools of available N in soil become depleted, but empirical support for such progressive N limitation has been lacking. Increased N acquisition from soil depleted in inorganic nitrogen requires stimulation of the microbial processing of organic N, possibly through increasing C supply to soil by plant roots or mycorrhizal hyphae. Increases in (mycorr)rhizosphere C fluxes could stimulate microbes to produce extra-cellular enzymes that release N from SOM, feeding back from soil microsites to ecosystem-scale processes. We investigated the influence of elevated CO2 on root exudation and soil enzyme activity at the Duke Forest FACE site, USA, where loblolly pine (Pinus taeda L.) stands have been exposed to elevated CO2 for 14 years and N fertilization for five years. In each plot, root boxes containing acetate windows were installed in 2008. Two years after installation, we collected soils adjacent to root tips (the rhizosphere), hyphal tips (the hyphosphere) and bulk soil. We measured in situ root exudation rates from intact pine roots. Study objectives were to analyze (i) the influence of atmospheric CO2 on root exudation and extra-cellular enzyme activities, (ii) the influence of soil N availability in regulating these activities, and (iii) the relationship between the activities of enzymes involved in N cycling in soils and gross N transformations at soil microsites. Elevated atmospheric CO2 significantly increased the activity of β-1-4-N-acetylglucosaminidase (NAG) in the rhizosphere by almost 2.5 times (39 to 95 nmol h-1 g-1), and 1.6fold in the hyphosphere relative to ambient plots. NAG is an enzyme involved in the degradation of chitin from the cell walls of soil organisms, releasing absorbable forms of nitrogen. The activity of peroxidase, which degrades aromatic C compounds of SOM, increased significantly in the

  7. Exogenous Methyl Jasmonate Treatment Increases Glucosinolate Biosynthesis and Quinone Reductase Activity in Kale Leaf Tissue

    PubMed Central

    Ku, Kang-Mo; Jeffery, Elizabeth H.; Juvik, John A.

    2014-01-01

    Methyl jasmonate (MeJA) spray treatments were applied to the kale varieties ‘Dwarf Blue Curled Vates’ and ‘Red Winter’ in replicated field plantings in 2010 and 2011 to investigate alteration of glucosinolate (GS) composition in harvested leaf tissue. Aqueous solutions of 250 µM MeJA were sprayed to saturation on aerial plant tissues four days prior to harvest at commercial maturity. The MeJA treatment significantly increased gluconasturtiin (56%), glucobrassicin (98%), and neoglucobrassicin (150%) concentrations in the apical leaf tissue of these genotypes over two seasons. Induction of quinone reductase (QR) activity, a biomarker for anti-carcinogenesis, was significantly increased by the extracts from the leaf tissue of these two cultivars. Extracts of apical leaf tissues had greater MeJA mediated increases in phenolics, glucosinolate concentrations, GS hydrolysis products, and QR activity than extracts from basal leaf tissue samples. The concentration of the hydrolysis product of glucoraphanin, sulforphane was significantly increased in apical leaf tissue of the cultivar ‘Red Winter’ in both 2010 and 2011. There was interaction between exogenous MeJA treatment and environmental conditions to induce endogenous JA. Correlation analysis revealed that indole-3-carbanol (I3C) generated from the hydrolysis of glucobrassicin significantly correlated with QR activity (r = 0.800, P<0.001). Concentrations required to double the specific QR activity (CD values) of I3C was calculated at 230 µM, which is considerably weaker at induction than other isothiocyanates like sulforphane. To confirm relationships between GS hydrolysis products and QR activity, a range of concentrations of MeJA sprays were applied to kale leaf tissues of both cultivars in 2011. Correlation analysis of these results indicated that sulforaphane, NI3C, neoascorbigen, I3C, and diindolylmethane were all significantly correlated with QR activity. Thus, increased QR activity may be due to

  8. Shed GP of Ebola Virus Triggers Immune Activation and Increased Vascular Permeability

    PubMed Central

    Escudero-Pérez, Beatriz; Volchkova, Valentina A.; Dolnik, Olga; Lawrence, Philip; Volchkov, Viktor E.

    2014-01-01

    During Ebola virus (EBOV) infection a significant amount of surface glycoprotein GP is shed from infected cells in a soluble form due to cleavage by cellular metalloprotease TACE. Shed GP and non-structural secreted glycoprotein sGP, both expressed from the same GP gene, have been detected in the blood of human patients and experimentally infected animals. In this study we demonstrate that shed GP could play a particular role during EBOV infection. In effect it binds and activates non-infected dendritic cells and macrophages inducing the secretion of pro- and anti-inflammatory cytokines (TNFα, IL1β, IL6, IL8, IL12p40, and IL1-RA, IL10). Activation of these cells by shed GP correlates with the increase in surface expression of co-stimulatory molecules CD40, CD80, CD83 and CD86. Contrary to shed GP, secreted sGP activates neither DC nor macrophages while it could bind DCs. In this study, we show that shed GP activity is likely mediated through cellular toll-like receptor 4 (TLR4) and is dependent on GP glycosylation. Treatment of cells with anti-TLR4 antibody completely abolishes shed GP-induced activation of cells. We also demonstrate that shed GP activity is negated upon addition of mannose-binding sera lectin MBL, a molecule known to interact with sugar arrays present on the surface of different microorganisms. Furthermore, we highlight the ability of shed GP to affect endothelial cell function both directly and indirectly, demonstrating the interplay between shed GP, systemic cytokine release and increased vascular permeability. In conclusion, shed GP released from virus-infected cells could activate non-infected DCs and macrophages causing the massive release of pro- and anti-inflammatory cytokines and effect vascular permeability. These activities could be at the heart of the excessive and dysregulated inflammatory host reactions to infection and thus contribute to high virus pathogenicity. PMID:25412102

  9. Acetic acid suppresses the increase in disaccharidase activity that occurs during culture of caco-2 cells.

    PubMed

    Ogawa, N; Satsu, H; Watanabe, H; Fukaya, M; Tsukamoto, Y; Miyamoto, Y; Shimizu, M

    2000-03-01

    To understand how blood glucose level is lowered by oral administration of vinegar, we examined effects of acetic acid on glucose transport and disaccharidase activity in Caco-2 cells. Cells were cultured for 15 d in a medium containing 5 mmol/L of acetic acid. This chronic treatment did not affect cell growth or viability, and furthermore, apoptotic cell death was not observed. Glucose transport, evaluated with a nonmetabolizable substrate, 3-O-methyl glucose, also was not affected. However, the increase of sucrase activity observed in control cells (no acetic acid) was significantly suppressed by acetic acid (P < 0.01). Acetic acid suppressed sucrase activity in concentration- and time-dependent manners. Similar treatments (5 mmol/L and 15 d) with other organic acids such as citric, succinic, L-maric, L-lactic, L-tartaric and itaconic acids, did not suppress the increase in sucrase activity. Acetic acid treatment (5 mmol/L and 15 d) significantly decreased the activities of disaccharidases (sucrase, maltase, trehalase and lactase) and angiotensin-I-converting enzyme, whereas the activities of other hydrolases (alkaline phosphatase, aminopeptidase-N, dipeptidylpeptidase-IV and gamma-glutamyltranspeptidase) were not affected. To understand mechanisms underlying the suppression of disaccharidase activity by acetic acid, Northern and Western analyses of the sucrase-isomaltase complex were performed. Acetic acid did not affect the de novo synthesis of this complex at either the transcriptional or translational levels. The antihyperglycemic effect of acetic acid may be partially due to the suppression of disaccharidase activity. This suppression seems to occur during the post-translational processing. PMID:10702577

  10. Yearning for connection? Loneliness is associated with increased ventral striatum activity to close others.

    PubMed

    Inagaki, Tristen K; Muscatell, Keely A; Moieni, Mona; Dutcher, Janine M; Jevtic, Ivana; Irwin, Michael R; Eisenberger, Naomi I

    2016-07-01

    Loneliness is a distressing state indicating that one's basic need for social connection is not being met. In an effort to satisfy the need for social connection, loneliness may increase the processing of social cues and desire to connect with others. Yet the neural substrates that contribute to the drive for increased connection in response to loneliness are not known. The ventral striatum (VS), previously shown to increase in response to craving food and other rewarding stimuli, may contribute to "social craving" when one is lonely. That is, the VS may track one's 'hunger' for reconnection much as it tracks hunger for food. To examine this, participants reported on their feelings of loneliness before undergoing an fMRI scan where they viewed cues of potential social reconnection (images of a close other). Consistent with the hypothesis that loneliness stems from an unmet need for connection, loneliness was associated with reduced feelings of connection with the close other. Furthermore, greater reported loneliness was associated with increased VS activity to viewing a close other (vs stranger). Results extend the current literature by showing that lonely individuals show increased activity in reward-related regions to their closest loved ones, possibly reflecting an increased desire for social connection. PMID:26084531

  11. Restraint stress increases hemichannel activity in hippocampal glial cells and neurons

    PubMed Central

    Orellana, Juan A.; Moraga-Amaro, Rodrigo; Díaz-Galarce, Raúl; Rojas, Sebastián; Maturana, Carola J.; Stehberg, Jimmy; Sáez, Juan C.

    2015-01-01

    Stress affects brain areas involved in learning and emotional responses, which may contribute in the development of cognitive deficits associated with major depression. These effects have been linked to glial cell activation, glutamate release and changes in neuronal plasticity and survival including atrophy of hippocampal apical dendrites, loss of synapses and neuronal death. Under neuro-inflammatory conditions, we recently unveiled a sequential activation of glial cells that release ATP and glutamate via hemichannels inducing neuronal death due to activation of neuronal NMDA/P2X7 receptors and pannexin1 hemichannels. In the present work, we studied if stress-induced glia activation is associated to changes in hemichannel activity. To this end, we compared hemichannel activity of brain cells after acute or chronic restraint stress in mice. Dye uptake experiments in hippocampal slices revealed that acute stress induces opening of both Cx43 and Panx1 hemichannels in astrocytes, which were further increased by chronic stress; whereas enhanced Panx1 hemichannel activity was detected in microglia and neurons after acute/chronic and chronic stress, respectively. Moreover, inhibition of NMDA/P2X7 receptors reduced the chronic stress-induced hemichannel opening, whereas blockade of Cx43 and Panx1 hemichannels fully reduced ATP and glutamate release in hippocampal slices from stressed mice. Thus, we propose that gliotransmitter release through hemichannels may participate in the pathogenesis of stress-associated psychiatric disorders and possibly depression. PMID:25883550

  12. Net Increase of platelet membrane tyrosine specific-protein kinase activity by phorbol myristate acetate

    SciTech Connect

    Ishihara, Noriko; Sakamoto, Hikaru; Iwama, Minako; Kobayashi, Bonro )

    1990-01-01

    Tyrosine protein kinase (TPK) activity in rabbit platelets after stimulation by phorbol myristate acetate (PMA) or thrombin was directly estimated by {sup 32}P incorporation from ({gamma}-{sup 32})ATP into synthetic peptide angiotensin II. By PMA-treatment a net increase of TPK activity was obtained, while thrombin acted on the TPK quickly but stimulation was limited within the range attained by the control after lengthy incubation. The responsive TPK to these stimulators was localized mainly in membrane but much less in cytosol. The specific activity of the particulate TPK was low in the sonicate of control ice cold platelets but increased about 6-fold when the platelets were incubated at 37{degree}C. On a brief contact of platelets with PMA at 37{degrees}C the TPK was fully activated and reached a maximum value about 130% of the control. Determination of phosphotyrosine phosphatase in the stimulated platelet sonicate revealed that its participation in the above described increase of {sup 32}P-incorporation was meagre. The quick response suggested a possible role of TPK in the signal transduction through the platelet cell membrane.

  13. PD-1 Increases PTEN Phosphatase Activity While Decreasing PTEN Protein Stability by Inhibiting Casein Kinase 2

    PubMed Central

    Patsoukis, Nikolaos; Li, Lequn; Sari, Duygu; Petkova, Victoria

    2013-01-01

    Programmed death 1 (PD-1) is a potent inhibitor of T cell responses. PD-1 abrogates activation of the phosphatidylinositol 3-kinase (PI3K)/Akt pathway, but the mechanism remains unclear. We determined that during T cell receptor (TCR)/CD3- and CD28-mediated stimulation, PTEN is phosphorylated by casein kinase 2 (CK2) in the Ser380-Thr382-Thr383 cluster within the C-terminal regulatory domain, which stabilizes PTEN, resulting in increased protein abundance but suppressed PTEN phosphatase activity. PD-1 inhibited the stabilizing phosphorylation of the Ser380-Thr382-Thr383 cluster within the C-terminal domain of PTEN, thereby resulting in ubiquitin-dependent degradation and diminished abundance of PTEN protein but increased PTEN phosphatase activity. These effects on PTEN were secondary to PD-1-mediated inhibition of CK2 and were recapitulated by pharmacologic inhibition of CK2 during TCR/CD3- and CD28-mediated stimulation without PD-1. Furthermore, PD-1-mediated diminished abundance of PTEN was reversed by inhibition of ubiquitin-dependent proteasomal degradation. Our results identify CK2 as a new target of PD-1 and reveal an unexpected mechanism by which PD-1 decreases PTEN protein expression while increasing PTEN activity, thereby inhibiting the PI3K/Akt signaling axis. PMID:23732914

  14. Activated polymorphonuclear cells increase sickle red blood cell retention in lung: role of phospholipids.

    PubMed

    Haynes, Johnson; Obiako, Boniface

    2002-01-01

    This study investigates the role of the activated polymorphonuclear cell (APMN) products on sickle red blood cell (SRBC) retention/adherence in the pulmonary circulation. Isolated rat lungs were perfused with (51)Cr-labeled normal RBCs (NRBC) or SRBCs (10% hematocrit) suspensions +/- PMNs. Specific activities of lung and perfusate were measured and retention (the number of SRBC/g lung) was calculated. SRBC retention was 3.5 times greater than NRBC retention. PMN activation was required to increase SRBC retention. Supernatants from APMN increased SRBC retention, which suggested soluble products such as oxidants, PAF, and/or leukotriene (LTB(4)) are involved. Heat inactivation of PMN NADPH oxidase had no effect on retention. Whereas neither platelet-activating factor (PAF) nor LTB(4) (secreted by APMN) increased SRBC retention, PAF+LTB(4) did. The PAF antagonist, WEB-2170, attenuated SRBC retention mediated by PAF+LTB(4) and APMNs. Similarly, zileuton (5-lipoxygenase inhibitor) attenuated APMN-mediated SRBC retention. We conclude the concomitant release of PAF and LTB(4) from APMN is involved in the initiation of microvascular occlusion by SRBCs in the perfused rat lung. PMID:11748055

  15. Prenatal Iron Deficiency in Guinea Pigs Increases Locomotor Activity but Does Not Influence Learning and Memory

    PubMed Central

    Fiset, Catherine; Rioux, France M.; Surette, Marc E.; Fiset, Sylvain

    2015-01-01

    The objective of the current study was to determine whether prenatal iron deficiency induced during gestation in guinea pigs affected locomotor activity and learning and memory processes in the progeny. Dams were fed either iron-deficient anemic or iron-sufficient diets throughout gestation and lactation. After weaning, all pups were fed an iron-sufficient diet. On postnatal day 24 and 40, the pups’ locomotor activity was observed within an open-field test, and from postnatal day 25 to 40, their learning and memory processes were assessed within a Morris Water Maze. The behavioural and cognitive tests revealed that the iron deficient pup group had increased locomotor activity, but solely on postnatal day 40, and that there were no group differences in the Morris Water Maze. In the general discussion, we propose that prenatal iron deficiency induces an increase in nervousness due to anxiety in the progeny, which, in the current study, resulted in an increase of locomotor activity. PMID:26186713

  16. Porcine malignant hyperthermia susceptibility: increased calcium-sequestering activity of skeletal muscle sarcoplasmic reticulum.

    PubMed Central

    O'Brien, P J

    1986-01-01

    This study tested the hypothesis that calcium-sequestration by isolated sarcoplasmic reticulum was abnormal in skeletal muscle of malignant hyperthermia-susceptible swine. A heavy sarcoplasmic reticulum fraction was isolated from malignant hyperthermia and control muscle using differential and density-gradient centrifugation. Prior to onset of malignant hyperthermia, calcium-sequestering activity (Vmax at 37 degrees C, mumol calcium/mg/min) was twofold increased in malignant hyperthermia sarcoplasmic reticulum compared to control sarcoplasmic reticulum (1.96 +/- 0.50 versus 4.00 +/- 0.87, P less than 0.01), although thermodynamic and kinetic properties of this activity were otherwise indistinguishable between groups. This increased activity of the malignant hyperthermia sarcoplasmic reticulum fraction was associated with twofold increased concentration of Ca-ATPase and calsequestrin protein. When a malignant hyperthermia-reaction developed, calcium-uptake was depressed to less than 5% of control values. These data indicate that malignant hyperthermia is not initiated due to a defect in the calcium-sequestration mechanism, however, loss of calcium-uptake activity occurring after the onset of malignant hyperthermia might result in the propagation and irreversibility of the malignant hyperthermia reaction. Images Fig. 1. PMID:3742368

  17. Prolonged daily light exposure increases body fat mass through attenuation of brown adipose tissue activity

    PubMed Central

    Kooijman, Sander; van den Berg, Rosa; Ramkisoensing, Ashna; Boon, Mariëtte R.; Kuipers, Eline N.; Loef, Marieke; Zonneveld, Tom C. M.; Lucassen, Eliane A.; Sips, Hetty C. M.; Chatzispyrou, Iliana A.; Houtkooper, Riekelt H.; Meijer, Johanna H.; Coomans, Claudia P.; Biermasz, Nienke R.; Rensen, Patrick C. N.

    2015-01-01

    Disruption of circadian rhythmicity is associated with obesity and related disorders, including type 2 diabetes and cardiovascular disease. Specifically, prolonged artificial light exposure associates with obesity in humans, although the underlying mechanism is unclear. Here, we report that increasing the daily hours of light exposure increases body adiposity through attenuation of brown adipose tissue (BAT) activity, a major contributor of energy expenditure. Mice exposed to a prolonged day length of 16- and 24-h light, compared with regular 12-h light, showed increased adiposity without affecting food intake or locomotor activity. Mechanistically, we demonstrated that prolonged day length decreases sympathetic input into BAT and reduces β3-adrenergic intracellular signaling. Concomitantly, prolonging day length decreased the uptake of fatty acids from triglyceride-rich lipoproteins, as well as of glucose from plasma selectively by BAT. We conclude that impaired BAT activity is an important mediator in the association between disturbed circadian rhythm and adiposity, and anticipate that activation of BAT may overcome the adverse metabolic consequences of disturbed circadian rhythmicity. PMID:25964318

  18. Increasing Level of Leisure Physical Activity Could Reduce the Risk of Hip Fracture in Older Women

    PubMed Central

    Rong, Ke; Liu, Xiao-yu; Wu, Xu-hua; Li, Xiao-liu; Xia, Qing-quan; Chen, Jiong; Yin, Xiao-fan

    2016-01-01

    Abstract We carried out the study to investigate and quantitatively assess the potential association between current level of physical activity and the risk of osteoporosis hip fracture in older women. Relevant publications before October 2015 were identified using the PubMed and Ovid searching tools. A dose–response meta-analysis was carried out to combine and analysis results. Fourteen prospective studies were included in the meta-analysis. A general analysis of 9 studies showed a significant inverse relationship between increasing level of physical activity and risk of hip fracture in older women [relative risk (RR) = 0.93, 95% confidence interval (95% CI): 0.91–0.96]. The result of a sensitivity analysis was consistent with the general analysis (RR = 0.94, 95% CI: 0.93–0.96). The association between increasing level of physical activity and risk of wrist fracture was not statistically significant in a general analysis of three studies (RR = 1.004, 95% CI: 0.98–1.03). A potential direct association between increasing level of physical activity and risk of wrist fracture was observed after removing 1 study with the greatest weight (RR = 1.01, 95% CI: 1.00–1.03). No significant publication bias was observed in our analysis. Our results show that increasing level of physical activity within an appropriate range may reduce the risk of hip fracture but not the risk of wrist fracture in older women. PMID:26986111

  19. Acute and chronic caffeine administration increases physical activity in sedentary adults.

    PubMed

    Schrader, Patrick; Panek, Leah M; Temple, Jennifer L

    2013-06-01

    Caffeine is a commonly used stimulant thought to have ergogenic properties. Most studies on the ergogenic effects of caffeine have been conducted in athletes. The purpose of this study was to test the hypothesis that caffeine reduces ratings of perceived exertion and increases liking of physical activity in sedentary adults. Participants completed treadmill walking at 60% to 70% of their maximal heart rate at baseline and for 6 subsequent visits, during which half of the participants were given caffeine (3 mg/kg) and half given placebo in a sports drink vehicle. To investigate the potential synergistic effects of acute and chronic caffeine on self-determined exercise duration, participants were rerandomized to either the same or different condition for the last visit, creating 4 chronic/acute treatment groups (placebo/placebo, placebo/caffeine, caffeine/placebo, caffeine/caffeine). Participants rated how much they liked the activity and perceived exertion at each visit. There was a main effect of time on liking of physical activity, with liking increasing over time and an interaction of sex and caffeine treatment on liking, with liking of activity increasing in female participants treated with caffeine, but not with placebo. There was no effect of caffeine on ratings of perceived exertion. Individuals who received caffeine on the final test day exercised for significantly longer than those who received placebo. These data suggest that repeated exposure to physical activity significantly increases liking of exercise and reduces ratings of perceived exertion and that caffeine does little to further modify these effects. PMID:23746561

  20. Calpain expression in lymphoid cells. Increased mRNA and protein levels after cell activation.

    PubMed

    Deshpande, R V; Goust, J M; Chakrabarti, A K; Barbosa, E; Hogan, E L; Banik, N L

    1995-02-10

    Although calpain is ubiquitously present in human tissues and is thought to play a role in demyelination, its activity is very low in resting normal lymphocytes. To determine the nature of calpain expression at the mRNA and protein levels in human lymphoid cells, we studied human T lymphocytic, B lymphocytic, and monocytic lines as well as peripheral blood mononuclear cells. Stimulation of cells with the phorbol ester phorbol myristate acetate and the calcium ionophore A23187 resulted in increased calpain mRNA and protein expression. Calpain mRNA expression is also increased in human T cells stimulated with anti-CD3. A dissociation between the increases of RNA and protein suggested that calpain could be released from the cells; the subsequent experiments showed its presence in the extracellular environment. 5,6-Dichloro-1b-D-ribofuranosylbenzimidazole, a reversible inhibitor of mRNA synthesis, reduced calpain mRNA levels by 50-67% and protein levels by 72-91%. Its removal resulted in resumption of both calpain mRNA and protein synthesis. Cycloheximide, a translational inhibitor, reduced calpain protein levels by 77-81% and calpain mRNA levels by 96% in activated THP-1 cells. Interferon-gamma induced calpain mRNA and protein in U-937 and THP-1 cells. Dexamethasone increased mRNA expression in THP-1 cells. Our results indicate that activation of lymphoid cells results in de novo synthesis and secretion of calpain. PMID:7852311

  1. Deletion of creB in Aspergillus oryzae increases secreted hydrolytic enzyme activity.

    PubMed

    Hunter, A J; Morris, T A; Jin, B; Saint, C P; Kelly, J M

    2013-09-01

    Aspergillus oryzae has been used in the food and beverage industry for centuries, and industrial strains have been produced by multiple rounds of selection. Targeted gene deletion technology is particularly useful for strain improvement in such strains, particularly when they do not have a well-characterized meiotic cycle. Phenotypes of an Aspergillus nidulans strain null for the CreB deubiquitinating enzyme include effects on growth and repression, including increased activity levels of various enzymes. We show that Aspergillus oryzae contains a functional homologue of the CreB deubiquitinating enzyme and that a null strain shows increased activity levels of industrially important secreted enzymes, including cellulases, xylanases, amylases, and proteases, as well as alleviated inhibition of spore germination on glucose medium. Reverse transcription-quantitative PCR (RT-qPCR) analysis showed that the increased levels of enzyme activity in both Aspergillus nidulans and Aspergillus oryzae are mirrored at the transcript level, indicating transcriptional regulation. We report that Aspergillus oryzae DAR3699, originally isolated from soy fermentation, has a similar phenotype to that of a creB deletion mutant of the RIB40 strain, and it contains a mutation in the creB gene. Collectively, the results for Aspergillus oryzae, Aspergillus nidulans, Trichoderma reesei, and Penicillium decumbens show that deletion of creB may be broadly useful in diverse fungi for increasing production of a variety of enzymes. PMID:23835170

  2. High phosphorylase activity is correlated with increased potato minituber formation and starch content during extended clinorotation

    NASA Astrophysics Data System (ADS)

    Nedukha, O. M.; Schnyukova, E. I.; Leach, J. E.

    2003-05-01

    The major purpose of these experiments were to investigate growth of potato storage organs and starch synthesis in minitubers at slow horizontal clinorotation (2 rpm), which partly mimics microgravity, and a secondary goal was to study the activity and localization of phosphorylase (EC 2.4.1.1) in storage parenchyma under these conditions. Miniplants of Solanum tuberosum L. (cv Adreta) were grown in culture for 30 days for both the vertical control and the horizontal clinorotation. During long-term clinorotation, an acceleration of minituber formation, and an increase of amyloplast number and size in storage parenchyma cells, as well as increased starch content, was observed in the minitubers. The differences among cytochemical reaction intensity, activity of phosphorylase, and carbohydrate content in storage parenchyma cells of minitubers grown in a horizontal clinostat were established by electron-cytochemical and biochemical methods. It is shown that high phosphorylase activity is correlated with increased starch content during extended clinorotation. The results demonstrate the increase in carbohydrate metabolism and possible accelerated growth of storage organs under the influence of microgravity, as mimicked by clinorotation; therefore, clinorotation can be used as a basis for future studies on mechanisms of starch synthesis under microgravity.

  3. Platelets mediate increased endothelium permeability in dengue through NLRP3-inflammasome activation

    PubMed Central

    Hottz, Eugenio D.; Lopes, Juliana F.; Freitas, Carla; Valls-de-Souza, Rogério; Oliveira, Marcus F.; Bozza, Marcelo T.; Da Poian, Andrea T.; Weyrich, Andrew S.; Zimmerman, Guy A.

    2013-01-01

    Dengue is the most frequent hemorrhagic viral disease and re-emergent infection in the world. Although thrombocytopenia is characteristically observed in mild and severe forms of dengue, the role of platelet activation in dengue pathogenesis has not been fully elucidated. We hypothesize that platelets have major roles in inflammatory amplification and increased vascular permeability during severe forms of dengue. Here we investigate interleukin (IL)-1β synthesis, processing, and secretion in platelets during dengue virus (DV) infection and potential contribution of these events to endothelial permeability during infection. We observed increased expression of IL-1β in platelets and platelet-derived microparticles from patients with dengue or after platelet exposure to DV in vitro. We demonstrated that DV infection leads to assembly of nucleotide-binding domain leucine rich repeat containing protein (NLRP3) inflammasomes, activation of caspase-1, and caspase-1–dependent IL-1β secretion. Our findings also indicate that platelet-derived IL-1β is chiefly released in microparticles through mechanisms dependent on mitochondrial reactive oxygen species–triggered NLRP3 inflammasomes. Inflammasome activation and platelet shedding of IL-1β–rich microparticles correlated with signs of increased vascular permeability. Moreover, microparticles from DV-stimulated platelets induced enhanced permeability in vitro in an IL-1–dependent manner. Our findings provide new evidence that platelets contribute to increased vascular permeability in DV infection by inflammasome-dependent release of IL-1β. PMID:24009231

  4. Deletion of creB in Aspergillus oryzae Increases Secreted Hydrolytic Enzyme Activity

    PubMed Central

    Hunter, A. J.; Morris, T. A.; Jin, B.; Saint, C. P.

    2013-01-01

    Aspergillus oryzae has been used in the food and beverage industry for centuries, and industrial strains have been produced by multiple rounds of selection. Targeted gene deletion technology is particularly useful for strain improvement in such strains, particularly when they do not have a well-characterized meiotic cycle. Phenotypes of an Aspergillus nidulans strain null for the CreB deubiquitinating enzyme include effects on growth and repression, including increased activity levels of various enzymes. We show that Aspergillus oryzae contains a functional homologue of the CreB deubiquitinating enzyme and that a null strain shows increased activity levels of industrially important secreted enzymes, including cellulases, xylanases, amylases, and proteases, as well as alleviated inhibition of spore germination on glucose medium. Reverse transcription-quantitative PCR (RT-qPCR) analysis showed that the increased levels of enzyme activity in both Aspergillus nidulans and Aspergillus oryzae are mirrored at the transcript level, indicating transcriptional regulation. We report that Aspergillus oryzae DAR3699, originally isolated from soy fermentation, has a similar phenotype to that of a creB deletion mutant of the RIB40 strain, and it contains a mutation in the creB gene. Collectively, the results for Aspergillus oryzae, Aspergillus nidulans, Trichoderma reesei, and Penicillium decumbens show that deletion of creB may be broadly useful in diverse fungi for increasing production of a variety of enzymes. PMID:23835170

  5. Carnitine Palmitoyltransferase 1 Increases Lipolysis, UCP1 Protein Expression and Mitochondrial Activity in Brown Adipocytes

    PubMed Central

    Calderon-Dominguez, María; Sebastián, David; Fucho, Raquel; Weber, Minéia; Mir, Joan F.; García-Casarrubios, Ester; Obregón, María Jesús; Zorzano, Antonio; Valverde, Ángela M.; Serra, Dolors

    2016-01-01

    The discovery of active brown adipose tissue (BAT) in adult humans and the fact that it is reduced in obese and diabetic patients have put a spotlight on this tissue as a key player in obesity-induced metabolic disorders. BAT regulates energy expenditure through thermogenesis; therefore, harnessing its thermogenic fat-burning power is an attractive therapeutic approach. We aimed to enhance BAT thermogenesis by increasing its fatty acid oxidation (FAO) rate. Thus, we expressed carnitine palmitoyltransferase 1AM (CPT1AM), a permanently active mutant form of CPT1A (the rate-limiting enzyme in FAO), in a rat brown adipocyte (rBA) cell line through adenoviral infection. We found that CPT1AM-expressing rBA have increased FAO, lipolysis, UCP1 protein levels and mitochondrial activity. Additionally, enhanced FAO reduced the palmitate-induced increase in triglyceride content and the expression of obese and inflammatory markers. Thus, CPT1AM-expressing rBA had enhanced fat-burning capacity and improved lipid-induced derangements. This indicates that CPT1AM-mediated increase in brown adipocytes FAO may be a new approach to the treatment of obesity-induced disorders. PMID:27438137

  6. Aversive emotional interference impacts behavior and prefronto-striatal activity during increasing attentional control

    PubMed Central

    Papazacharias, Apostolos; Taurisano, Paolo; Fazio, Leonardo; Gelao, Barbara; Di Giorgio, Annabella; Lo Bianco, Luciana; Quarto, Tiziana; Mancini, Marina; Porcelli, Annamaria; Romano, Raffaella; Caforio, Grazia; Todarello, Orlando; Popolizio, Teresa; Blasi, Giuseppe; Bertolino, Alessandro

    2015-01-01

    Earlier studies have demonstrated that emotional stimulation modulates attentional processing during goal-directed behavior and related activity of a brain network including the inferior frontal gyrus (IFG) and the caudate nucleus. However, it is not clear how emotional interference modulates behavior and brain physiology during variation in attentional control, a relevant question for everyday life situations in which both emotional stimuli and cognitive load vary. The aim of this study was to investigate the impact of negative emotions on behavior and activity in IFG and caudate nucleus during increasing levels of attentional control. Twenty two healthy subjects underwent event-related functional magnetic resonance imaging while performing a task in which neutral or fearful facial expressions were displayed before stimuli eliciting increasing levels of attentional control processing. Results indicated slower reaction time (RT) and greater right IFG activity when fearful compared with neutral facial expressions preceded the low level of attentional control. On the other hand, fearful facial expressions preceding the intermediate level of attentional control elicited faster behavioral responses and greater activity in the right and left sides of the caudate. Finally, correlation analysis indicated a relationship between behavioral correlates of attentional control after emotional interference and right IFG activity. All together, these results suggest that the impact of negative emotions on attentional processing is differentially elicited at the behavioral and physiological levels as a function of cognitive load. PMID:25954172

  7. Magnesium ions increase the activity of Bacillus deramificans pullulanase expressed by Brevibacillus choshinensis.

    PubMed

    Zou, Chun; Duan, Xuguo; Wu, Jing

    2016-08-01

    Addition of MgCl2 to the culture medium has been found to dramatically increase the activity of Bacillus deramificans pullulanase expressed by Brevibacillus choshinensis. The specific activity of the pullulanase obtained from medium supplemented with MgCl2 was also higher than that obtained in culture medium without added magnesium ions. In this work, the mechanism of this increase was studied. When cultured in medium without added magnesium ions, B. choshinensis mainly produced a thermolabile, inactive form of pullulanase. The addition of magnesium ions led to the production of a thermostable, active form of pullulanase. Circular dichroism assays revealed considerable differences in secondary structure between the active and inactive pullulanase forms. Transmission electron microscopy suggested that magnesium ion addition inhibits the shedding of cell wall protein (HWP) layers from the cell surface. Quantitative real-time PCR showed that magnesium ion addition represses transcription of HWP. Because the pullulanase gene and HWP have identical promoters, pullulanase gene transcription was also inhibited. These results suggest that when pullulanase is expressed slowly, it tends to fold into an active form. PMID:27026175

  8. Aversive emotional interference impacts behavior and prefronto-striatal activity during increasing attentional control.

    PubMed

    Papazacharias, Apostolos; Taurisano, Paolo; Fazio, Leonardo; Gelao, Barbara; Di Giorgio, Annabella; Lo Bianco, Luciana; Quarto, Tiziana; Mancini, Marina; Porcelli, Annamaria; Romano, Raffaella; Caforio, Grazia; Todarello, Orlando; Popolizio, Teresa; Blasi, Giuseppe; Bertolino, Alessandro

    2015-01-01

    Earlier studies have demonstrated that emotional stimulation modulates attentional processing during goal-directed behavior and related activity of a brain network including the inferior frontal gyrus (IFG) and the caudate nucleus. However, it is not clear how emotional interference modulates behavior and brain physiology during variation in attentional control, a relevant question for everyday life situations in which both emotional stimuli and cognitive load vary. The aim of this study was to investigate the impact of negative emotions on behavior and activity in IFG and caudate nucleus during increasing levels of attentional control. Twenty two healthy subjects underwent event-related functional magnetic resonance imaging while performing a task in which neutral or fearful facial expressions were displayed before stimuli eliciting increasing levels of attentional control processing. Results indicated slower reaction time (RT) and greater right IFG activity when fearful compared with neutral facial expressions preceded the low level of attentional control. On the other hand, fearful facial expressions preceding the intermediate level of attentional control elicited faster behavioral responses and greater activity in the right and left sides of the caudate. Finally, correlation analysis indicated a relationship between behavioral correlates of attentional control after emotional interference and right IFG activity. All together, these results suggest that the impact of negative emotions on attentional processing is differentially elicited at the behavioral and physiological levels as a function of cognitive load. PMID:25954172

  9. Activation of mitochondrial calpain and increased cardiac injury: beyond AIF release.

    PubMed

    Thompson, Jeremy; Hu, Ying; Lesnefsky, Edward J; Chen, Qun

    2016-02-01

    Calpain 1 (CPN1) is a ubiquitous cysteine protease that exists in both cytosol and cardiac mitochondria. Mitochondrial CPN1 (mit-CPN1) is located in the intermembrane space and matrix. Activation of mit-CPN1 within the intermembrane space increases cardiac injury by releasing apoptosis-inducing factor from mitochondria during ischemia-reperfusion (IR). We asked if activation of mit-CPN1 is involved in mitochondrial injury during IR. MDL-28170 (MDL) was used to inhibit CPN1 in buffer-perfused hearts following 25-min ischemia and 30-min reperfusion. MDL treatment decreased the release of lactate dehydrogenase into coronary effluent compared with untreated hearts, indicating that inhibition of CPN1 decreases cardiac injury. MDL also prevented the cleavage of spectrin (a substrate of CPN1) in cytosol during IR, supporting that MDL treatment decreased cytosolic calpain activation. In addition, MDL markedly improved calcium retention capacity compared with untreated heart, suggesting that MDL treatment decreases mitochondrial permeability transition pore opening. In addition, we found that IR led to decreased complex I activity, whereas inhibition of mit-CPN1 using MDL protected complex I. Pyruvate dehydrogenase content was decreased following IR. However, pyruvate dehydrogenase content was preserved in MDL-treated mitochondria. Taken together, MDL treatment decreased cardiac injury during IR by inhibiting both cytosolic and mit-CPN1. Activation of mit-CPN1 increases cardiac injury during IR by sensitizing mitochondrial permeability transition pore opening and impairing mitochondrial metabolism through damage of complex I. PMID:26637561

  10. A stable phage lysin (Cpl-1) dimer with increased antipneumococcal activity and decreased plasma clearance.

    PubMed

    Resch, Gregory; Moreillon, Philippe; Fischetti, Vincent A

    2011-12-01

    Bacteriophages (phages) produce endolysins (lysins) as part of their lytic cycle in order to degrade the peptidoglycan layer of the infected bacteria for subsequent release of phage progeny. Because these enzymes maintain their lytic and lethal activity against Gram-positive bacteria when added extrinsically to the cells, they have been actively exploited as novel anti-infectives, sometimes termed enzybiotics. As with other relatively small peptides, one issue in their clinical development is their rapid inactivation through proteolytic degradation, immunological blockage and renal clearance. The antipneumococcal lysin Cpl-1 was shown to escape both proteolysis and immunological blockage. However, its short plasma half-life (20.5 min in mice) may represent a shortcoming for clinical usefulness. Here we report the construction of a Cpl-1 dimer with a view to increasing both the antipneumococcal specific activity and plasma half-life of Cpl-1. Dimerisation was achieved by introducing specific cysteine residues at the C-terminal end of the enzyme, thus favouring disulphide bonding. Compared with the native monomer, the constructed dimer demonstrated a two-fold increase in specific antipneumococcal activity and a ca. ten-fold decrease in plasma clearance. As several lysins are suspected to dimerise on contact with their cell wall substrate to be fully active, stable pre-dimerised enzymes may represent a more efficient alternative to the native monomer. PMID:21982146

  11. Transient increase in phosphatidylinositol 3,4-bisphosphate and phosphatidylinositol trisphosphate during activation of human neutrophils

    SciTech Connect

    Traynor-Kaplan, A.E.; Thompson, B.L.; Harris, A.L.; Taylor, P.; Omann, G.M.; Sklar, L.A. )

    1989-09-15

    We recently showed that phosphatidylinositol trisphosphate (PIP3) was present in a unique lipid fraction generated in neutrophils during activation. Here, we demonstrate that the band containing this fraction isolated from thin layer chromatography consists primarily of PIP3 and that only small amounts of radiolabeled PIP3 exist prior to activation. In addition, high performance liquid chromatography of deacylated phospholipids from stimulated cells reveals an increase in a fraction eluting ahead of glycerophosphoinositol 4,5-P2. After removal of the glycerol we found that it coeluted with inositol 1,3,4-P3 when resubjected to high performance liquid chromatography. Thus, we have detected a second, novel form of phosphatidylinositol bisphosphate in activated neutrophils, PI-(3,4)P2. The elevation of PIP3 through the formyl peptide receptor is blocked by pretreatment with pertussis toxin, implicating mediation of the increase in PIP3 by a guanosine triphosphate-binding (G) protein. The rise in PIP3 is not secondary to calcium elevation. Buffering the rise in intracellular calcium did not diminish the increase in PIP3. The elevation of PIP3 appears to occur during activation with physiological agonists, its level varying with the degree of activation. Leukotriene B4, which elicits many of the same responses as stimulation of the formyl peptide receptor but with minimal oxidant production, stimulates a much attenuated rise in PIP3. Isoproterenol, which inhibits oxidant production also reduces the rise in PIP3. Hence formation of PI(3,4)P2 and PIP3 (presumed to be PI(3,4,5)P3) correlates closely with the early events of neutrophil activation.

  12. Increased Feeding Speed Is Associated with Higher Subsequent Sympathetic Activity in Dogs.

    PubMed

    Ohtani, Nobuyo; Okamoto, Yuta; Tateishi, Kanako; Uchiyama, Hidehiko; Ohta, Mitsuaki

    2015-01-01

    Although the domestication process has altered the feeding behavior of dogs, some breeds still demonstrate a remarkable ability to gorge, and will eat exceptionally large quantities of food whenever it is available. Lesions in the ventromedial hypothalamus increase appetite and lead to obesity, suggesting that the autonomic nervous system plays an important role in feeding. Focusing on the autonomic activities closely involved in food intake, we investigated sympathetic activities before and after feeding in dogs. The subjects were 56 healthy dogs of 21 different breeds (29 males and 27 females). Based on feeding habits, the 56 dogs were divided into three groups: Fast (n = 19), Slow (n = 24) and Leftover (n = 13). The feeding speed and the amount of food per mouthful of the Fast dogs were significantly greater than those of the Slow and the Leftover dogs. The plasma norepinephrine level in dogs of the Fast group was significantly increased after feeding, while those in the Slow and Leftover groups were significantly decreased after feeding, compared with the pre-feeding concentrations. The low frequency/high frequency ratio of heart rate variability is a good indicator of sympathetic activity and was also significantly higher in the Fast group than in the other groups. Delayed feeding using automatic feeding equipment decreased the plasma norepinephrine concentration and low frequency/high frequency ratio observed after feeding in dogs of the Fast group. In conclusion, dogs eating rapidly with less chewing, which indicates increased sympathetic activity during feeding, may benefit from delayed feeding. The slow eating may activate the parasympathetic nervous system after feeding, which could enhance the activity of the digestive system. PMID:26569112

  13. Increased RNA-Induced Silencing Complex (RISC) Activity Contributes to Hepatocellular Carcinoma

    PubMed Central

    Yoo, Byoung Kwon; Santhekadur, Prasanna K.; Gredler, Rachel; Chen, Dong; Emdad, Luni; Bhutia, Sujit; Pannell, Lewis; Fisher, Paul B.; Sarkar, Devanand

    2011-01-01

    There is virtually no effective treatment for advanced hepatocellular carcinoma (HCC) and novel targets need to be identified to develop effective treatment. We recently documented that the oncogene Astrocyte elevated gene-1 (AEG-1) plays a seminal role in hepatocarcinogenesis. Employing yeast two-hybrid assay and co-immunoprecipitation followed by mass spectrometry we identified Staphylococcal nuclease domain containing 1 (SND1), a nuclease in the RNA-induced silencing complex (RISC) facilitating RNAi-mediated gene silencing, as an AEG-1 interacting protein. Co-immunoprecipitation and co-localization studies confirmed that AEG-1 is also a component of RISC and both AEG-1 and SND1 are required for optimum RISC activity facilitating siRNA and miRNA-mediated silencing of luciferase reporter gene. In 109 human HCC samples SND1 was overexpressed in ∼74% cases compared to normal liver. Correspondingly, significantly higher RISC activity was observed in human HCC cells compared to immortal normal hepatocytes. Increased RISC activity, conferred by AEG-1 or SND1, resulted in increased degradation of tumor suppressor mRNAs that are target of oncomiRs. Inhibition of enzymatic activity of SND1 significantly inhibited proliferation of human HCC cells. As a corollary, stable overexpression of SND1 augmented and siRNA-mediated inhibition of SND1 abrogated growth of human HCC cells in vitro and in vivo thus revealing a potential role of SND1 in hepatocarcinogenesis. Conclusion We unravel a novel mechanism that overexpression of AEG-1 and SND1 leading to increased RISC activity might contribute to hepatocarcinogenesis. Targeted inhibition of SND1 enzymatic activity might be developed as an effective therapy for HCC. PMID:21520169

  14. Increased Feeding Speed Is Associated with Higher Subsequent Sympathetic Activity in Dogs

    PubMed Central

    Ohtani, Nobuyo; Okamoto, Yuta; Tateishi, Kanako; Uchiyama, Hidehiko; Ohta, Mitsuaki

    2015-01-01

    Although the domestication process has altered the feeding behavior of dogs, some breeds still demonstrate a remarkable ability to gorge, and will eat exceptionally large quantities of food whenever it is available. Lesions in the ventromedial hypothalamus increase appetite and lead to obesity, suggesting that the autonomic nervous system plays an important role in feeding. Focusing on the autonomic activities closely involved in food intake, we investigated sympathetic activities before and after feeding in dogs. The subjects were 56 healthy dogs of 21 different breeds (29 males and 27 females). Based on feeding habits, the 56 dogs were divided into three groups: Fast (n = 19), Slow (n = 24) and Leftover (n = 13). The feeding speed and the amount of food per mouthful of the Fast dogs were significantly greater than those of the Slow and the Leftover dogs. The plasma norepinephrine level in dogs of the Fast group was significantly increased after feeding, while those in the Slow and Leftover groups were significantly decreased after feeding, compared with the pre-feeding concentrations. The low frequency/high frequency ratio of heart rate variability is a good indicator of sympathetic activity and was also significantly higher in the Fast group than in the other groups. Delayed feeding using automatic feeding equipment decreased the plasma norepinephrine concentration and low frequency/high frequency ratio observed after feeding in dogs of the Fast group. In conclusion, dogs eating rapidly with less chewing, which indicates increased sympathetic activity during feeding, may benefit from delayed feeding. The slow eating may activate the parasympathetic nervous system after feeding, which could enhance the activity of the digestive system. PMID:26569112

  15. Transient increase in phosphatidylinositol 3,4-bisphosphate and phosphatidylinositol trisphosphate during activation of human neutrophils.

    PubMed

    Traynor-Kaplan, A E; Thompson, B L; Harris, A L; Taylor, P; Omann, G M; Sklar, L A

    1989-09-15

    We recently showed that phosphatidylinositol trisphosphate (PIP3) was present in a unique lipid fraction generated in neutrophils during activation. Here, we demonstrate that the band containing this fraction isolated from thin layer chromatography consists primarily of PIP3 and that only small amounts of radiolabeled PIP3 exist prior to activation. In addition, high performance liquid chromatography of deacylated phospholipids from stimulated cells reveals an increase in a fraction eluting ahead of glycerophosphoinositol 4,5-P2. After removal of the glycerol we found that it coeluted with inositol 1,3,4-P3 when resubjected to high performance liquid chromatography. Thus, we have detected a second, novel form of phosphatidylinositol bisphosphate in activated neutrophils, PI-(3,4)P2. The elevation of PIP3 through the formyl peptide receptor is blocked by pretreatment with pertussis toxin, implicating mediation of the increase in PIP3 by a guanosine triphosphate-binding (G) protein. The rise in PIP3 is not secondary to calcium elevation. Buffering the rise in intracellular calcium did not diminish the increase in PIP3. The elevation of PIP3 appears to occur during activation with physiological agonists, its level varying with the degree of activation. Leukotriene B4, which elicits many of the same responses as stimulation of the formyl peptide receptor but with minimal oxidant production, stimulates a much attenuated rise in PIP3. Isoproterenol, which inhibits oxidant production also reduces the rise in PIP3. Hence formation of PI(3,4)P2 and PIP3 (presumed to be PI(3,4,5)P3) correlates closely with the early events of neutrophil activation. PMID:2549071

  16. The stress response neuropeptide CRF increases amyloid-β production by regulating γ-secretase activity

    PubMed Central

    Park, Hyo-Jin; Ran, Yong; Jung, Joo In; Holmes, Oliver; Price, Ashleigh R; Smithson, Lisa; Ceballos-Diaz, Carolina; Han, Chul; Wolfe, Michael S; Daaka, Yehia; Ryabinin, Andrey E; Kim, Seong-Hun; Hauger, Richard L; Golde, Todd E; Felsenstein, Kevin M

    2015-01-01

    The biological underpinnings linking stress to Alzheimer's disease (AD) risk are poorly understood. We investigated how corticotrophin releasing factor (CRF), a critical stress response mediator, influences amyloid-β (Aβ) production. In cells, CRF treatment increases Aβ production and triggers CRF receptor 1 (CRFR1) and γ-secretase internalization. Co-immunoprecipitation studies establish that γ-secretase associates with CRFR1; this is mediated by β-arrestin binding motifs. Additionally, CRFR1 and γ-secretase co-localize in lipid raft fractions, with increased γ-secretase accumulation upon CRF treatment. CRF treatment also increases γ-secretase activityin vitro, revealing a second, receptor-independent mechanism of action. CRF is the first endogenous neuropeptide that can be shown to directly modulate γ-secretase activity. Unexpectedly, CRFR1 antagonists also increased Aβ. These data collectively link CRF to increased Aβ through γ-secretase and provide mechanistic insight into how stress may increase AD risk. They also suggest that direct targeting of CRF might be necessary to effectively modulate this pathway for therapeutic benefit in AD, as CRFR1 antagonists increase Aβ and in some cases preferentially increase Aβ42 via complex effects on γ-secretase. PMID:25964433

  17. Cyclothiazide-induced persistent increase in respiratory-related activity in vitro

    PubMed Central

    Babiec, Walter E; Faull, Kym F; Feldman, Jack L

    2012-01-01

    Hypoglossal (XII) motoneurons (MNs) innervate the genioglossus muscle of the tongue, which plays an important role in maintaining upper airway patency, particularly during sleep, and modulating upper airway resistance. Discovering methods for inducing long-term increases in genioglossal motoneuronal excitability to AMPA-mediated drive may help in the development of therapeutics for upper airway motor disorders such as obstructive sleep apnoea. We show that the diuretic, anti-hypertensive, AMPA receptor modulator cyclothiazide (CTZ) induces a profound and long-lasting increase in the amplitude of respiratory-related XII nerve activity in rhythmically active neonatal rat medullary slices. Treatment of the slice with CTZ (90 μm) for 1 h increased the integrated XII (∫XII) nerve burst amplitude to 262 ± 23% of pre-treatment control at 1 h post-treatment; much of this increase lasted at least 12 h. The amount of CTZ-induced facilitation (CIF) was dependent upon both CTZ dose and exposure time and was accompanied by a long-lasting increase in endogenous AMPA-mediated drive currents to XII MNs. CIF, however, is not a form of plasticity and does not depend on AMPA or NMDA receptor activation for its induction. Nor does it depend on coincident protein kinase A or C activity. Rather, measurement of mEPSCs along with mass spectrometric analysis of CTZ-treated slices indicates that the cause is prolonged bioavailability of CTZ. These results illustrate a latent residual capacity for potentiating AMPA-mediated inspiratory drive to XII MNs that might be applied to the treatment of upper airway motor deficits. PMID:22753547

  18. Acrolein activates matrix metalloproteinases by increasing reactive oxygen species in macrophages

    SciTech Connect

    O'Toole, Timothy E. Zheng Yuting; Hellmann, Jason; Conklin, Daniel J.; Barski, Oleg; Bhatnagar, Aruni

    2009-04-15

    Acrolein is a ubiquitous component of environmental pollutants such as automobile exhaust, cigarette, wood, and coal smoke. It is also a natural constituent of several foods and is generated endogenously during inflammation or oxidation of unsaturated lipids. Because increased inflammation and episodic exposure to acrolein-rich pollutants such as traffic emissions or cigarette smoke have been linked to acute myocardial infarction, we examined the effects of acrolein on matrix metalloproteinases (MMPs), which destabilize atherosclerotic plaques. Our studies show that exposure to acrolein resulted in the secretion of MMP-9 from differentiated THP-1 macrophages. Acrolein-treatment of macrophages also led to an increase in reactive oxygen species (ROS), free intracellular calcium ([Ca{sup 2+}]{sub i}), and xanthine oxidase (XO) activity. ROS production was prevented by allopurinol, but not by rotenone or apocynin and by buffering changes in [Ca{sup 2+}]{sub I} with BAPTA-AM. The increase in MMP production was abolished by pre-treatment with the antioxidants Tiron and N-acetyl cysteine (NAC) or with the xanthine oxidase inhibitors allopurinol or oxypurinol. Finally, MMP activity was significantly stimulated in aortic sections from apoE-null mice containing advanced atherosclerotic lesions after exposure to acrolein ex vivo. These observations suggest that acrolein exposure results in MMP secretion from macrophages via a mechanism that involves an increase in [Ca{sup 2+}]{sub I}, leading to xanthine oxidase activation and an increase in ROS production. ROS-dependent activation of MMPs by acrolein could destabilize atherosclerotic lesions during brief episodes of inflammation or pollutant exposure.

  19. Overexpression of α-synuclein simultaneously increases glutamate NMDA receptor phosphorylation and reduces glucocerebrosidase activity.

    PubMed

    Yang, Junfeng; Hertz, Ellen; Zhang, Xiaoqun; Leinartaité, Lina; Lundius, Ebba Gregorsson; Li, Jie; Svenningsson, Per

    2016-01-12

    Progressive accumulation of α-synuclein (α-syn)-containing protein aggregates throughout the nervous system is a pathological hallmark of Parkinson's disease (PD). The mechanisms whereby α-syn exerts neurodegeneration remain to be fully understood. Here we show that overexpression of α-syn in transgenic mice leads to increased phosphorylation of glutamate NMDA receptor (NMDAR) subunits NR1 and NR2B in substantia nigra and striatum as well as reduced glucocerebrosidase (GCase) levels. Similarly, molecular studies performed in mouse N2A cells stably overexpressing human α-syn ((α-syn)N2A) showed that phosphorylation states of the same NMDAR subunits were increased, whereas GCase levels and lysosomal GCase activity were reduced. (α-syn)N2A cells showed an increased sensitivity to neurotoxicity towards 6-hydroxydopamine and NMDA. However, wildtype N2A, but not (α-syn)N2A cells, showed a further reduction in viability when co-incubated with 6-hydroxydopamine and the lysosomal inhibitors NH4Cl and leupeptin, suggesting that α-syn per se perturbs lysosomal functions. NMDA treatment reduced lysosomal GCase activity to the same extent in (α-syn)N2A cells as in wildtype N2A cells, indicating that the α-syn-dependent difference in NMDA neurotoxicity is unrelated to an altered GCase activity. Nevertheless, these data provide molecular evidence that overexpression of α-syn simultaneously induces two potential neurotoxic hits by increasing glutamate NMDA receptor phosphorylation, consistent with increased NMDA receptors functionality, and reducing GCase activity. PMID:26610904

  20. Piper betle shows antioxidant activities, inhibits MCF-7 cell proliferation and increases activities of catalase and superoxide dismutase

    PubMed Central

    2012-01-01

    Background Breast cancer is the most common form of cancer and the focus on finding chemotherapeutic agents have recently shifted to natural products. Piper betle is a medicinal plant with various biological activities. However, not much data is available on the anti-cancer effects of P. betle on breast cancer. Due to the current interest in the potential effects of antioxidants from natural products in breast cancer treatment, we investigated the antioxidant activities of the leaves of P. betle and its inhibitory effect on the proliferation of the breast cancer cell line, MCF-7. Methods The leaves of P. betle were extracted with solvents of varying polarities (water, methanol, ethyl acetate and hexane) and their phenolic and flavonoid content were determined using colorimetric assays. Phenolic composition was characterized using HPLC. Antioxidant activities were measured using FRAP, DPPH, superoxide anion, nitric oxide and hyroxyl radical scavenging assays. Biological activities of the extracts were analysed using MTT assay and antioxidant enzyme (catalase, superoxide dismutase, glutathione peroxidase) assays in MCF-7 cells. Results Overall, the ethyl acetate extract showed the highest ferric reducing activity and radical scavenging activities against DPPH, superoxide anion and nitric oxide radicals. This extract also contained the highest phenolic content implying the potential contribution of phenolics towards the antioxidant activities. HPLC analyses revealed the presence of catechin, morin and quercetin in the leaves. The ethyl acetate extract also showed the highest inhibitory effect against the proliferation of MCF-7 cells (IC50=65 μg/ml). Treatment of MCF-7 cells with the plant extract increased activities of catalase and superoxide dismutase. Conclusions Ethyl acetate is the optimal solvent for the extraction of compounds with antioxidant and anti-proliferative activities. The increased activities of catalase and superoxide dismutase in the treated cells

  1. Leptin differentially increases sympathetic nerve activity and its baroreflex regulation in female rats: role of oestrogen

    PubMed Central

    Shi, Zhigang; Brooks, Virginia L

    2015-01-01

    Key points Leptin increases sympathetic nerve activity (SNA) in males, which contributes to obesity-induced hypertension; however, whether leptin is equally effective in females is unknown. We report that leptin does increase SNA and heart rate in female rats; however, for lumbar and renal SNA, this action is only evident in pro-oestrus and in oestrogen-treated ovariectomized rats, but not in ovariectomized or dioestrus rats. Leptin increases SNA and heart rate similarly in male and pro-oestrus female rats; however, leptin increases arterial pressure only in males. Blockade of MC3/4 receptors in the paraventricular nucleus (PVN) with SHU9119 decreases SNA in leptin-treated pro-oestrus rats, suggesting that leptin increases SNA in part by increasing α-melanocyte-stimulating hormone drive of PVN presympathetic neurons. Our data establish sex differences in leptin's effects to increase SNA and arterial pressure, which emphasizes the need for enhanced recognition and investigation of sex differences in obesity-induced sympathoexcitation and hypertension. Abstract Obesity and hypertension are commonly associated, and activation of the sympathetic nervous system is considered to be a major contributor, at least in part due to the central actions of leptin. However, while leptin increases sympathetic nerve activity (SNA) in males, whether leptin is equally effective in females is unknown. Here, we show that intracerebroventricular (i.c.v.) leptin increases lumbar (LSNA) and renal (RSNA) SNA and baroreflex control of LSNA and RSNA in α-chloralose anaesthetized female rats, but only during pro-oestrus. In contrast, i.c.v. leptin increased basal and baroreflex control of splanchnic SNA (SSNA) and heart rate (HR) in rats in both the pro-oestrus and dioestrus states. The effects of leptin on basal LSNA, RSNA, SSNA and HR were similar in males and pro-oestrus females; however, i.c.v. leptin increased mean arterial pressure (MAP) only in males. Leptin did not alter LSNA or HR

  2. Increased Risk of Active Tuberculosis following Acute Kidney Injury: A Nationwide, Population-Based Study

    PubMed Central

    Chang, Chia-Hsui; Huang, Hui-Yu; Huang, Tao-Min; Lai, Chun-Fu; Lin, Meng-Chun; Ko, Wen-Je; Wu, Kwan-Dun; Yu, Chong-Jen; Shu, Chin-Chung; Lee, Chih-Hsin; Wang, Jann-Yuan

    2013-01-01

    Background Profound alterations in immune responses associated with uremia and exacerbated by dialysis increase the risk of active tuberculosis (TB). Evidence of the long-term risk and outcome of active TB after acute kidney injury (AKI) is limited. Methods This population-based-cohort study used claim records retrieved from the Taiwan National Health Insurance database. We retrieved records of all hospitalized patients, more than 18 years, who underwent dialysis for acute kidney injury (AKI) during 1999–2008 and validated using the NSARF data. Time-dependent Cox proportional hazards model to adjust for the ongoing effect of end-stage renal disease (ESRD) was conducted to predict long-term de novo active TB after discharge from index hospitalization. Results Out of 2,909 AKI dialysis patients surviving 90 days after index discharge, 686 did not require dialysis after hospital discharge. The control group included 11,636 hospital patients without AKI, dialysis, or history of TB. The relative risk of active TB in AKI dialysis patients, relative to the general population, after a mean follow-up period of 3.6 years was 7.71. Patients who did (hazard ratio [HR], 3.84; p<0.001) and did not (HR, 6.39; p<0.001) recover from AKI requiring dialysis had significantly higher incidence of TB than patients without AKI. The external validated data also showed nonrecovery subgroup (HR = 4.37; p = 0.049) had high risk of developing active TB compared with non-AKI. Additionally, active TB was associated with long-term all-cause mortality after AKI requiring dialysis (HR, 1.34; p = 0.032). Conclusions AKI requiring dialysis seems to independently increase the long-term risk of active TB, even among those who weaned from dialysis at discharge. These results raise concerns that the increasing global burden of AKI will in turn increase the incidence of active TB. PMID:23936044

  3. Histone deacetylase inhibitors increase glucocerebrosidase activity in Gaucher disease by modulation of molecular chaperones

    PubMed Central

    Yang, Chunzhang; Rahimpour, Shervin; Lu, Jie; Pacak, Karel; Ikejiri, Barbara; Brady, Roscoe O.; Zhuang, Zhengping

    2013-01-01

    Gaucher disease is caused by mutations of the GBA gene that encodes the lysosomal enzyme glucocerebrosidase (GCase). GBA mutations often result in protein misfolding and premature degradation, but usually exert less effect on catalytic activity. In this study, we identified the molecular mechanism by which histone deacetylase inhibitors increase the quantity and activity of GCase. Specifically, these inhibitors limit the deacetylation of heat shock protein 90, resulting in less recognition of the mutant peptide and GCase degradation. These findings provide insight into a possible therapeutic strategy for Gaucher disease and other genetic disorders by modifying molecular chaperone and protein degradation pathways. PMID:23277556

  4. Term myometrium is characterized by increased activating epigenetic modifications at the progesterone receptor-A promoter.

    PubMed

    Chai, S Y; Smith, R; Zakar, T; Mitchell, C; Madsen, G

    2012-08-01

    Term human myometrial expression of progesterone receptor (PR)-A is increased relative to PR-B, and as PR-A is a repressor of progesterone action mediated through PR-B, this increase may mediate the withdrawal of progesterone action and precipitate the onset of labour. PR-A and PR-B expression is regulated by two separate promoters of the PR gene. We hypothesized that epigenetic histone modifications at the two promoters contribute to the labour-associated regulation of PR-A and PR-B expression in term myometrium. PR total, PR-B and PR-A mRNA levels were determined using quantitative real-time PCR, and chromatin immunoprecipitation was used to determine the levels of activating and repressive histone modifications at the PR-A and PR-B promoters in human myometrial samples not in labour (n = 4) and in labour (n = 4). Chromatin extracts were immunoprecipitated with antibodies against activating (histone H3 and H4 acetylation and histone H3 lysine 4 trimethylation), and repressive (histone H3 lysine 9 trimethylation, histone H3 lysine 27 trimethylation and asymmetrical histone H3 arginine 2 dimethylation) histone modifications. PR-A mRNA levels increased during labour, while PR-B mRNA levels remained constant resulting in an increase of PR-A/PR-B mRNA ratio, as expected. Regardless of labour status, significantly higher levels of the activating histone modifications were found at the PR-A promoter compared with the PR-B promoter (P <0.001). H3K4me3 increased significantly at both promoters with labour onset (P =0.001). Low levels of the repressive histone modifications were also present at both promoters, with no labour-associated changes observed. Our data indicate that the PR-A promoter is epigenetically marked for activation in term myometrium more extensively than the PR-B promoter, and that labour is associated with an increase in H3K4me3 activating modification, consistent with the previously described increase in PR protein at this time. PMID:22369759

  5. Increased oxygen consumption following activation of brain: theoretical footnotes using spectroscopic data from barrel cortex.

    PubMed

    Mayhew, J; Johnston, D; Martindale, J; Jones, M; Berwick, J; Zheng, Y

    2001-06-01

    Optical imaging spectroscopy (OIS) and laser Doppler flowmetry (LDF) data sequences from anesthetized rats were used to determine the relationship between changes in oxy-and deoxygenated hemoglobin concentration and changes in blood volume and flow in the presence and absence of stimulation. The data from Jones et al. (accompanying paper) were used to explore the differences between two theoretical models of flow activation coupling. The essential difference between the two models is the extension of the model of Buxton and Frank by Hyder et al. (1998, J. Appl. Physiol. 85: 554--564) to incorporate change in capillary diffusivity coupled to flow. In both models activation-increased flow changes increase oxygen transport from the capillary; however, in Hyder et al.'s model the diffusivity of the capillary itself is increased. Hyder et al. proposed a parameter (Omega), a scaling "constant" linking increased blood flow and oxygen "diffusivity" in the capillary bed. Thus, in Buxton and Frank's theory, Omega = 0; i.e., there are no changes in diffusivity. In Hyder et al.'s theory, 0 < Omega < 1, and changes in diffusivity are assumed to be linearly related to flow changes. We elaborate the theoretical position of both models to show that, in principle, the different predictions from the two theories can be evaluated using optical imaging spectroscopy data. We find that both theoretical positions have limitations when applied to data from brief stimulation and when applied to data from mild hypercapnia. In summary, the analysis showed that although Hyder et al.'s proposal that diffusivity increased during activation did occur; it was shown to arise from an implementation of Buxton and Frank's theory under episodes of brief stimulation. The results also showed that the scaling parameter Omega is not a constant as the Hyder et al. model entails but in fact varies over the time course of the flow changes. Data from experiments in which mild hypercapnia was administered also

  6. Mechanosensitive activation of CFTR by increased cell volume and hydrostatic pressure but not shear stress.

    PubMed

    Vitzthum, Constanze; Clauss, Wolfgang G; Fronius, Martin

    2015-11-01

    The cystic fibrosis transmembrane conductance regulator (CFTR) is a Cl(-) channel that is essential for electrolyte and fluid homeostasis. Preliminary evidence indicates that CFTR is a mechanosensitive channel. In lung epithelia, CFTR is exposed to different mechanical forces such as shear stress (Ss) and membrane distention. The present study questioned whether Ss and/or stretch influence CFTR activity (wild type, ∆F508, G551D). Human CFTR (hCFTR) was heterologously expressed in Xenopus oocytes and the response to the mechanical stimulus and forskolin/IBMX (FI) was measured by two-electrode voltage-clamp experiments. Ss had no influence on hCFTR activity. Injection of an intracellular analogous solution to increase cell volume alone did not affect hCFTR activity. However, hCFTR activity was augmented by injection after pre-stimulation with FI. The response to injection was similar in channels carrying the common mutations ∆F508 and G551D compared to wild type hCFTR. Stretch-induced CFTR activation was further assessed in Ussing chamber measurements using Xenopus lung preparations. Under control conditions increased hydrostatic pressure (HP) decreased the measured ion current including activation of a Cl(-) secretion that was unmasked by the CFTR inhibitor GlyH-101. These data demonstrate activation of CFTR in vitro and in a native pulmonary epithelium in response to mechanical stress. Mechanosensitive regulation of CFTR is highly relevant for pulmonary physiology that relies on ion transport processes facilitated by pulmonary epithelial cells. PMID:26357939

  7. Meta-analysis of internet-delivered interventions to increase physical activity levels

    PubMed Central

    2012-01-01

    Many internet-delivered physical activity behaviour change programs have been developed and evaluated. However, further evidence is required to ascertain the overall effectiveness of such interventions. The objective of the present review was to evaluate the effectiveness of internet-delivered interventions to increase physical activity, whilst also examining the effect of intervention moderators. A systematic search strategy identified relevant studies published in the English-language from Pubmed, Proquest, Scopus, PsychINFO, CINHAL, and Sport Discuss (January 1990 – June 2011). Eligible studies were required to include an internet-delivered intervention, target an adult population, measure and target physical activity as an outcome variable, and include a comparison group that did not receive internet-delivered materials. Studies were coded independently by two investigators. Overall effect sizes were combined based on the fixed effect model. Homogeneity and subsequent exploratory moderator analysis was undertaken. A total of 34 articles were identified for inclusion. The overall mean effect of internet-delivered interventions on physical activity was d = 0.14 (p = 0.00). Fixed-effect analysis revealed significant heterogeneity across studies (Q = 73.75; p = 0.00). Moderating variables such as larger sample size, screening for baseline physical activity levels and the inclusion of educational components significantly increased intervention effectiveness. Results of the meta-analysis support the delivery of internet-delivered interventions in producing positive changes in physical activity, however effect sizes were small. The ability of internet-delivered interventions to produce meaningful change in long-term physical activity remains unclear. PMID:22546283

  8. ATM increases activation-induced cytidine deaminase activity at downstream S regions during class-switch recombination.

    PubMed

    Khair, Lyne; Guikema, Jeroen E J; Linehan, Erin K; Ucher, Anna J; Leus, Niek G J; Ogilvie, Colin; Lou, Zhenkun; Schrader, Carol E; Stavnezer, Janet

    2014-05-15

    Activation-induced cytidine deaminase (AID) initiates Ab class-switch recombination (CSR) in activated B cells resulting in exchanging the IgH C region and improved Ab effector function. During CSR, AID instigates DNA double-strand break (DSB) formation in switch (S) regions located upstream of C region genes. DSBs are necessary for CSR, but improper regulation of DSBs can lead to chromosomal translocations that can result in B cell lymphoma. The protein kinase ataxia telangiectasia mutated (ATM) is an important proximal regulator of the DNA damage response (DDR), and translocations involving S regions are increased in its absence. ATM phosphorylates H2AX, which recruits other DNA damage response (DDR) proteins, including mediator of DNA damage checkpoint 1 (Mdc1) and p53 binding protein 1 (53BP1), to sites of DNA damage. As these DDR proteins all function to promote repair and recombination of DSBs during CSR, we examined whether mouse splenic B cells deficient in these proteins would show alterations in S region DSBs when undergoing CSR. We find that in atm(-/-) cells Sμ DSBs are increased, whereas DSBs in downstream Sγ regions are decreased. We also find that mutations in the unrearranged Sγ3 segment are reduced in atm(-/-) cells. Our data suggest that ATM increases AID targeting and activity at downstream acceptor S regions during CSR and that in atm(-/-) cells Sμ DSBs accumulate as they lack a recombination partner. PMID:24729610

  9. Increased oxidative activity in human blood neutrophils and monocytes after spinal cord injury.

    PubMed

    Bao, Feng; Bailey, Christopher S; Gurr, Kevin R; Bailey, Stewart I; Rosas-Arellano, M Patricia; Dekaban, Gregory A; Weaver, Lynne C

    2009-02-01

    Traumatic injury can cause a systemic inflammatory response, increasing oxidative activity of circulating leukocytes and potentially exacerbating the original injury, as well as causing damage to initially unaffected organs. Although the importance of intraspinal inflammation after human spinal cord injury is appreciated, the role of the systemic inflammatory response to this injury is not widely recognised. We investigated oxidative activity of blood leukocytes from nine cord-injured subjects and six trauma controls (bone fractures without CNS injury) at 6 h-2 weeks after injury, comparing values to those of ten uninjured subjects. Neutrophil and monocyte free radical production, evaluated by flow cytometry, increased significantly more in cord injury subjects than in trauma controls (6-fold vs 50% increases). In leukocyte homogenates, the concentration of free radicals increased significantly more in cord injury subjects (2-fold) than in the trauma controls (1.6-fold) as did activity of myeloperoxidase (2.3-fold vs. 1.7-fold). Moreover, in homogenates and blood smears, expression of the NADPH oxidase subunit gp91(phox) and of the oxidative enzyme, inducible nitric oxide synthetase was 20-25% greater in cord injury subjects than in trauma controls. Expression of the pro-inflammatory transcription factor NF-kappaB and of cyclooxygenase-2 increased similarly after both injuries. Finally, aldehyde products of tissue-damaging lipid peroxidation also increased significantly more in the plasma of spinal cord injury subjects than in trauma controls (2.6 fold vs. 1.9-fold). Spinal cord injury causes a particularly intense systemic inflammatory response. Limiting this response briefly after cord injury should protect the spinal cord and tissues/organs outside the CNS from secondary damage. PMID:19056384

  10. ALDH2 Activator Inhibits Increased Myocardial Infarction Injury by Nitroglycerin Tolerance

    PubMed Central

    Sun, Lihan; Ferreira, Julio Cesar Batista; Mochly-Rosen, Daria

    2012-01-01

    Nitroglycerin, which helps impaired cardiac function as it is converted to nitric oxide, is used worldwide to treat patients with various ischemic and congestive cardiac diseases, including angina pectoris. Nevertheless, after continuous treatment, the benefits of nitroglycerin are limited by the development of tolerance to the drug. Nitroglycerin tolerance is a result of inactivation of aldehyde dehydrogenase 2 (ALDH2), an enzyme essential for cardioprotection in animals subjected to myocardial infarction (MI). Here we tested the hypothesis that the tolerance that develops as a result of sustained nitroglycerin treatment increases cardiac injury by subsequent MI. In a rat model of MI, 16 hours of prior, sustained nitroglycerin treatment (7.2 mg/kg/day) resulted in infarcts that were twice as large as those in untreated control animals and in diminished cardiac function at 3 days and 2 weeks after the MI. We also sought to identify a potential treatment to protect against this increased cardiac damage. Nitroglycerin inhibited ALDH2 activity in vitro, an effect that was blocked by Alda-1, an activator of ALDH2. Co-administration of Alda-1 (16 mg/kg/day) with the nitroglycerin prevented the nitroglycerin-induced increase in cardiac dysfunction after MI in rats, at least in part by enhancing metabolism of reactive aldehyde adducts that impair normal protein functions. If our animal studies showing that nitroglycerin tolerance increases cardiac injury upon ischemic insult are corroborated in humans, activators of ALDH2 such as Alda-1 may help to protect MI patients from this nitroglycerin-induced increase in cardiac injury, while maintaining the cardiac benefits of the increased nitric oxide concentrations produced by nitroglycerin. PMID:22049071

  11. Circulating Myeloid-Derived Suppressor Cells Are Increased and Activated in Pulmonary Hypertension

    PubMed Central

    Nguyen, Cecilia M.; Belchenko, Dmitry D.; Colvin, Kelley L.; Takatsuki, Shinichi; Ivy, D. Dunbar; Stenmark, Kurt R.

    2012-01-01

    Background: Myeloid-derived suppressor cells (MDSCs) are increased in inflammatory and autoimmune disorders and orchestrate immune cell responses therein. Pulmonary hypertension (PH) is associated with inflammation, autoimmunity, and lung vascular remodeling. Immature myeloid cells are found in the lungs of humans and animals with PH, and we hypothesized that they would be increased in the blood of patients with PH compared with control subjects. Methods: Twenty-six children with PH and 10 undergoing cardiac catheterization for arrhythmia ablation were studied. Five milliliters of fresh blood were analyzed using flow cytometry. Results were confirmed using magnetic bead sorting and immunofluorescence, while quantitative polymerase chain reaction and intracellular urea concentration assays were used as measures of MDSC arginase-1 activation. Results: Flow cytometry demonstrated enrichment of circulating MDSCs among patients with PH (n = 26; mean, 0.271 × 106 cells/mL ± 0.17; 1.86% of CD45+ population ± 1.51) compared with control subjects (n = 10; mean, 0.176 × 106 cells/mL ± 0.05; 0.57% of CD45+ population ± 0.29; P < .05). Higher numbers of circulating MDSCs correlated to increasing mean pulmonary artery pressure (r = 0.510, P < .05). Among patients with PH, female patients had a twofold increase in MDSCs compared with male patients. Immunofluorescence analysis confirmed the results of flow cytometry. Quantitative reverse transcription polymerase chain reaction assay results for arginase-1 and measurement of intracellular urea concentration revealed increased activity of MDSCs from patients with PH compared with control subjects. Conclusions: Circulating activated MDSCs are significantly increased in children with PH compared with control subjects. Further investigation of these cells is warranted, and we speculate that they might play significant immunomodulatory roles in the disease pathogenesis of PH. PMID:21940769

  12. Selective downregulation of mitochondrial electron transport chain activity and increased oxidative stress in human atrial fibrillation.

    PubMed

    Emelyanova, Larisa; Ashary, Zain; Cosic, Milanka; Negmadjanov, Ulugbek; Ross, Gracious; Rizvi, Farhan; Olet, Susan; Kress, David; Sra, Jasbir; Tajik, A Jamil; Holmuhamedov, Ekhson L; Shi, Yang; Jahangir, Arshad

    2016-07-01

    Mitochondria are critical for maintaining normal cardiac function, and a deficit in mitochondrial energetics can lead to the development of the substrate that promotes atrial fibrillation (AF) and its progression. However, the link between mitochondrial dysfunction and AF in humans is still not fully defined. The aim of this study was to elucidate differences in the functional activity of mitochondrial oxidative phosphorylation (OXPHOS) complexes and oxidative stress in right atrial tissue from patients without (non-AF) and with AF (AF) who were undergoing open-heart surgery and were not significantly different for age, sex, major comorbidities, and medications. The overall functional activity of the electron transport chain (ETC), NADH:O2 oxidoreductase activity, was reduced by 30% in atrial tissue from AF compared with non-AF patients. This was predominantly due to a selective reduction in complex I (0.06 ± 0.007 vs. 0.09 ± 0.006 nmol·min(-1)·citrate synthase activity(-1), P = 0.02) and II (0.11 ± 0.012 vs. 0.16 ± 0.012 nmol·min(-1)·citrate synthase activity(-1), P = 0.003) functional activity in AF patients. Conversely, complex V activity was significantly increased in AF patients (0.21 ± 0.027 vs. 0.12 ± 0.01 nmol·min(-1)·citrate synthase activity(-1), P = 0.005). In addition, AF patients exhibited a higher oxidative stress with increased production of mitochondrial superoxide (73 ± 17 vs. 11 ± 2 arbitrary units, P = 0.03) and 4-hydroxynonenal level (77.64 ± 30.2 vs. 9.83 ± 2.83 ng·mg(-1) protein, P = 0.048). Our findings suggest that AF is associated with selective downregulation of ETC activity and increased oxidative stress that can contribute to the progression of the substrate for AF. PMID:27199126

  13. Sustained increase in hippocampal sharp-wave ripple activity during slow-wave sleep after learning

    PubMed Central

    Eschenko, Oxana; Ramadan, Wiâm; Mölle, Matthias; Born, Jan; Sara, Susan J.

    2008-01-01

    High-frequency oscillations, known as sharp-wave/ripple (SPW-R) complexes occurring in hippocampus during slow-wave sleep (SWS), have been proposed to promote synaptic plasticity necessary for memory consolidation. We recorded sleep for 3 h after rats were trained on an odor-reward association task. Learning resulted in an increased number SPW-Rs during the first hour of post-learning SWS. The magnitude of ripple events and their duration were also elevated for up to 2 h after the newly formed memory. Rats that did not learn the discrimination during the training session did not show any change in SPW-Rs. Successful retrieval from remote memory was likewise accompanied by an increase in SPW-R density and magnitude, relative to the previously recorded baseline, but the effects were much shorter lasting and did not include increases in ripple duration and amplitude. A short-lasting increase of ripple activity was also observed when rats were rewarded for performing a motor component of the task only. There were no increases in ripple activity after habituation to the experimental environment. These experiments show that the characteristics of hippocampal high-frequency oscillations during SWS are affected by prior behavioral experience. Associative learning induces robust and sustained (up to 2 h) changes in several SPW-R characteristics, while after retrieval from remote memory or performance of a well-trained procedural aspect of the task, only transient changes in ripple density were induced. PMID:18385477

  14. Children with High Functioning Autism show increased prefrontal and temporal cortex activity during error monitoring

    PubMed Central

    Goldberg, Melissa C.; Spinelli, Simona; Joel, Suresh; Pekar, James J.; Denckla, Martha B.; Mostofsky, Stewart H.

    2010-01-01

    Evidence exists for deficits in error monitoring in autism. These deficits may be particularly important because they may contribute to excessive perseveration and repetitive behavior in autism. We examined the neural correlates of error monitoring using fMRI in 8–12-year-old children with high-functioning autism (HFA, n=11) and typically developing children (TD, n=15) during performance of a Go/No-Go task by comparing the neural correlates of commission errors versus correct response inhibition trials. Compared to TD children, children with HFA showed increased BOLD fMRI signal in the anterior medial prefrontal cortex (amPFC) and the left superior temporal gyrus (STempG) during commission error (versus correct inhibition) trials. A follow-up region-of-interest analysis also showed increased BOLD signal in the right insula in HFA compared to TD controls. Our findings of increased amPFC and STempG activity in HFA, together with the increased activity in the insula, suggest a greater attention towards the internally-driven emotional state associated with making an error in children with HFA. Since error monitoring occurs across different cognitive tasks throughout daily life, an increased emotional reaction to errors may have important consequences for early learning processes. PMID:21151713

  15. Reduced RKIP enhances nasopharyngeal carcinoma radioresistance by increasing ERK and AKT activity

    PubMed Central

    Yuan, Li; Yi, Hong-Mei; Yi, Hong; Qu, Jia-Quan; Zhu, Jin-Feng; Li, Li-Na; Xiao, Ta; Zheng, Zhen; Lu, Shan-Shan; Xiao, Zhi-Qiang

    2016-01-01

    Raf kinase inhibitory protein (RKIP) functions as a chemo-immunotherapeutic sensitizer of cancers, but regulation of RKIP on tumor radiosensitivity remains largely unexplored. In this study, we investigate the role and mechanism of RKIP in nasopharyngeal carcinoma (NPC) radioresistance. The results showed that RKIP was frequently downregulated in the radioresistant NPC tissues compared with radiosensitive NPC tissues, and its reduction correlated with NPC radioresistance and poor patient survival, and was an independent prognostic factor. In vitro radioresponse assay showed that RKIP overexpression decreased while RKIP knockdown increased NPC cell radioresistance. In the NPC xenografts, RKIP overexpression decreased while RKIP knockdown increased tumor radioresistance. Mechanistically, RKIP reduction promoted NPC cell radioresistance by increasing ERK and AKT activity, and AKT may be a downstream transducer of ERK signaling. Moreover, the levels of phospho-ERK−1/2 and phospho-AKT were increased in the radioresistant NPC tissues compared with radiosensitive ones, and negatively associated with RKIP expression, indicating that RKIP-regulated NPC radioresponse is mediated by ERK and AKT signaling in the clinical samples. Our data demonstrate that RKIP is a critical determinant of NPC radioresponse, and its reduction enhances NPC radioresistance through increasing ERK and AKT signaling activity, highlighting the therapeutic potential of RKIP-ERK-AKT signaling axis in NPC radiosensitization. PMID:26862850

  16. Focused campaign increases activity among participants in Nature's Notebook, a citizen science project

    USGS Publications Warehouse

    Crimmins, Theresa M.; Weltzin, Jake F.; Rosemartin, Alyssa H.; Surina, Echo M.; Marsh, Lee; Denny, Ellen G.

    2014-01-01

    Citizen science projects, which engage non-professional scientists in one or more stages of scientific research, have been gaining popularity; yet maintaining participants’ activity level over time remains a challenge. The objective of this study was to evaluate the potential for a short-term, focused campaign to increase participant activity in a national-scale citizen science program. The campaign that we implemented was designed to answer a compelling scientific question. We invited participants in the phenology-observing program, Nature’s Notebook, to track trees throughout the spring of 2012, to ascertain whether the season arrived as early as the anomalous spring of 2010. Consisting of a series of six electronic newsletters and costing our office slightly more than 1 week of staff resources, our effort was successful; compared with previous years, the number of observations collected in the region where the campaign was run increased by 184%, the number of participants submitting observations increased by 116%, and the number of trees registered increased by 110%. In comparison, these respective metrics grew by 25, 55, and 44%, over previous years, in the southeastern quadrant of the United States, where no such campaign was carried out. The campaign approach we describe here is a model that could be adapted by a wide variety of programs to increase engagement and thereby positively influence participant retention.

  17. Enhanced Enzyme Kinetic Stability by Increasing Rigidity within the Active Site*

    PubMed Central

    Xie, Yuan; An, Jiao; Yang, Guangyu; Wu, Geng; Zhang, Yong; Cui, Li; Feng, Yan

    2014-01-01

    Enzyme stability is an important issue for protein engineers. Understanding how rigidity in the active site affects protein kinetic stability will provide new insight into enzyme stabilization. In this study, we demonstrated enhanced kinetic stability of Candida antarctica lipase B (CalB) by mutating the structurally flexible residues within the active site. Six residues within 10 Å of the catalytic Ser105 residue with a high B factor were selected for iterative saturation mutagenesis. After screening 2200 colonies, we obtained the D223G/L278M mutant, which exhibited a 13-fold increase in half-life at 48 °C and a 12 °C higher T5015, the temperature at which enzyme activity is reduced to 50% after a 15-min heat treatment. Further characterization showed that global unfolding resistance against both thermal and chemical denaturation also improved. Analysis of the crystal structures of wild-type CalB and the D223G/L278M mutant revealed that the latter formed an extra main chain hydrogen bond network with seven structurally coupled residues within the flexible α10 helix that are primarily involved in forming the active site. Further investigation of the relative B factor profile and molecular dynamics simulation confirmed that the enhanced rigidity decreased fluctuation of the active site residues at high temperature. These results indicate that enhancing the rigidity of the flexible segment within the active site may provide an efficient method for improving enzyme kinetic stability. PMID:24448805

  18. Hospital acquired pneumonia with high-risk bacteria is associated with increased pulmonary matrix metalloproteinase activity

    PubMed Central

    Schaaf, Bernhard; Liebau, Cornelia; Kurowski, Volkhard; Droemann, Daniel; Dalhoff, Klaus

    2008-01-01

    Background Neutrophil products like matrix metalloproteinases (MMP), involved in bacterial defence mechanisms, possibly induce lung damage and are elevated locally during hospital- acquired pneumonia (HAP). In HAP the virulence of bacterial species is known to be different. The aim of this study was to investigate the influence of high-risk bacteria like S. aureus and pseudomonas species on pulmonary MMPconcentration in human pneumonia. Methods In 37 patients with HAP and 16 controls, MMP-8, MMP-9 and tissue inhibitors of MMP (TIMP) were analysed by ELISA and MMP-9 activity using zymography in bronchoalveolar lavage (BAL). Results MMP-9 activity in mini-BAL was increased in HAP patients versus controls (149 ± 41 vs. 34 ± 11, p < 0.0001). In subgroup analysis, the highest MMP concentrations and activity were seen in patients with high-risk bacteria: patients with high-risk bacteria MMP-9 1168 ± 266 vs. patients with low-risk bacteria 224 ± 119 ng/ml p < 0.0001, MMP-9 gelatinolytic activity 325 ± 106 vs. 67 ± 14, p < 0.0002. In addition, the MMP-8 and MMP-9 concentration was associated with the state of ventilation and systemic inflammatory marker like CRP. Conclusion Pulmonary MMP concentrations and MMP activity are elevated in patients with HAP. This effect is most pronounced in patients with high-risk bacteria. Artificial ventilation may play an additional role in protease activation. PMID:18700005

  19. AMPK activation promotes lipid droplet dispersion on detyrosinated microtubules to increase mitochondrial fatty acid oxidation

    PubMed Central

    Herms, Albert; Bosch, Marta; Reddy, Babu J.N.; Schieber, Nicole L.; Fajardo, Alba; Rupérez, Celia; Fernández-Vidal, Andrea; Ferguson, Charles; Rentero, Carles; Tebar, Francesc; Enrich, Carlos; Parton, Robert G.; Gross, Steven P.; Pol, Albert

    2015-01-01

    Lipid droplets (LDs) are intracellular organelles that provide fatty acids (FAs) to cellular processes including synthesis of membranes and production of metabolic energy. While known to move bidirectionally along microtubules (MTs), the role of LD motion and whether it facilitates interaction with other organelles are unclear. Here we show that during nutrient starvation, LDs and mitochondria relocate on detyrosinated MT from the cell centre to adopt a dispersed distribution. In the cell periphery, LD–mitochondria interactions increase and LDs efficiently supply FAs for mitochondrial beta-oxidation. This cellular adaptation requires the activation of the energy sensor AMPK, which in response to starvation simultaneously increases LD motion, reorganizes the network of detyrosinated MTs and activates mitochondria. In conclusion, we describe the existence of a specialized cellular network connecting the cellular energetic status and MT dynamics to coordinate the functioning of LDs and mitochondria during nutrient scarcity. PMID:26013497

  20. Downregulation of vitellogenin gene activity increases the gustatory responsiveness of honey bee workers (Apis mellifera)

    PubMed Central

    Amdam, Gro V.; Norberg, Kari; Page, Robert E.; Erber, Joachim; Scheiner, Ricarda

    2008-01-01

    In the honey bee (Apis mellifera), young workers usually perform tasks in the nest while older workers forage in the field. The behavioral shift from nest-task to foraging activity is accompanied by physiological and sensory changes so that foragers can be characterized by a higher juvenile hormone (JH) level, a lower vitellogenin protein titer, and an increased responsiveness to water and sucrose stimuli. JH was hypothesized to be the key mediator of behavioral development, physiology, and sensory sensitivity in honey bee workers. Recent research, however, has shown that JH is controlled by the hemolymph vitellogenin level, which implies that the fat body specific vitellogenin gene can be a key regulator of behavioral change. Here, we show that downregulation of vitellogenin activity by RNA interference (RNAi) causes an increase in the gustatory responsiveness of worker bees. Our observations suggest that vitellogenin is an important regulator of long-term changes in honey bee behavior. PMID:16466813

  1. Synthetic ceramide analogues increase amyloid-β 42 production by modulating γ-secretase activity.

    PubMed

    Takasugi, Nobumasa; Sasaki, Tomoki; Shinohara, Mitsuru; Iwatsubo, Takeshi; Tomita, Taisuke

    2015-02-01

    γ-Secretase cleaves amyloid β-precursor protein (APP) to generate amyloid-β peptide (Aβ), which is a causative molecule of Alzheimer disease (AD). The C-terminal length of Aβ, which is determined by γ-secretase activity, determines the aggregation and deposition profiles of Aβ, thereby affecting the onset of AD. In this study, we found that the synthetic ceramide analogues dl-threo-1-phenyl-2-decanoylamino-3-morpholino-1-propanol (PDMP) and (1S,2R-d-erythro-2-N-myristoylamino)-1-phenyl-1-propanol (DMAPP) modulated γ-secretase-mediated cleavage to increase Aβ42 production. Unexpectedly, PDMP and DMAPP upregulated Aβ42 production independent of alteration of ceramide metabolism. Our results propose that synthetic ceramide analogues function as novel γ-secretase modulators that increase Aβ42, and this finding might lead to the understanding of the effect of the lipid environment on γ-secretase activity. PMID:25545059

  2. Spectral Analysis of the Signals Associated with Increased Activity in Popocatepetl Volcano April 2012

    NASA Astrophysics Data System (ADS)

    Cuenca, J.

    2013-05-01

    After several decades of being inactive in 1994 had a strong reactivation. Since then he has had long periods where volcanic activity including increased growth and destruction of a dome. In April 2012 Popocatepetl Volcano activity showed an increase in the emission of gas and ash, and Vulcanian type explosions. As a result the National Center for Disaster Prevention (CENAPRED) raised the yellow phase from 2 to 3. Spectrally analyzes seismic activity characteristic of the types of events (explosions, LP, Type-B and tremors) that provides information of the source processes that cause it, despite sustained change reflected by the complexity of the volcanic apparatus, through of: 1) the spectral content of the process provides the source, 2) the spectral ratio H / V, its associated amplification and dominant frequencies, 3) time frequency analysis showing the variation in frequency, 4) the particle motion to analyze its retrograde or prograde acting in a volcanic complex medium. The calculation of H / V was performed by each hour using windows with duration of 80 seconds in the broadband seismic station "Canario" (PPPB). The predominant frequencies of H / V are around 1.4-1.8 Hz to 2.1-2.6 Hz and amplifications from 2.3 to 6.9 times. Analysis of H / V of 48 hours (days 16 and April 17) for the case of 1.4-1.8 Hz was observed: (1) From 0-9 hours there is no amplification. (2) The seismic amplification increases from 10 to 11 hours. (3) A first crisis reaches a maximum at 13 hours with about 6 times of amplification. (4) From 14 to 15 hours there is a strong relaxation of the activity. (5) The activity begins to increase from 16 to 23 hours where it reaches its maximum amplification of almost 7 times. (6) The following two hours and is kept exceeding 6 times of amplification. (7) Then is followed by a decrease to 4 hours on the day 17, from which is maintained at a level variable. (8) At 18 hours of the day 17 grows the amplification at 6.2 times, which conforms a

  3. PPARγ-mediated increase in glucose availability sustains chronic Brucella abortus infection in alternatively activated macrophages

    PubMed Central

    Xavier, Mariana N.; Winter, Maria G.; Spees, Alanna M.; den Hartigh, Andreas B.; Nguyen, Kim; Roux, Christelle M.; Silva, Teane M. A.; Atluri, Vidya L.; Kerrinnes, Tobias; Keestra, A. Marijke; Monack, Denise M.; Luciw, Paul A.; Eigenheer, Richard A.; Bäumler, Andreas J.; Santos, Renato L.; Tsolis, Renée M.

    2013-01-01

    SUMMARY Eradication of persistent intracellular bacterial pathogens with antibiotic therapy is often slow or incomplete. However, strategies to augment antibiotics are hampered by our poor understanding of the nutritional environment that sustains chronic infection. Here we show that the intracellular pathogen Brucella abortus survives and replicates preferentially in alternatively activated macrophages (AAM), which are more abundant during chronic infection. A metabolic shift induced by peroxisome proliferator activated receptor γ (PPARγ), which increases intracellular glucose availability, is identified as a causal mechanism promoting enhanced bacterial survival in AAM. Glucose uptake was crucial for increased replication of B. abortus in AAM, and chronic infection, as inactivation of the bacterial glucose transporter gluP reduced both intracellular survival in AAM and persistence in mice. Thus, a shift in intracellular nutrient availability induced by PPARγ promotes chronic persistence of B. abortus within AAM and targeting this pathway may aid in eradicating chronic infection. PMID:23954155

  4. PPARγ-mediated increase in glucose availability sustains chronic Brucella abortus infection in alternatively activated macrophages.

    PubMed

    Xavier, Mariana N; Winter, Maria G; Spees, Alanna M; den Hartigh, Andreas B; Nguyen, Kim; Roux, Christelle M; Silva, Teane M A; Atluri, Vidya L; Kerrinnes, Tobias; Keestra, A Marijke; Monack, Denise M; Luciw, Paul A; Eigenheer, Richard A; Bäumler, Andreas J; Santos, Renato L; Tsolis, Renée M

    2013-08-14

    Eradication of persistent intracellular bacterial pathogens with antibiotic therapy is often slow or incomplete. However, strategies to augment antibiotics are hampered by our poor understanding of the nutritional environment that sustains chronic infection. Here we show that the intracellular pathogen Brucella abortus survives and replicates preferentially in alternatively activated macrophages (AAMs), which are more abundant during chronic infection. A metabolic shift induced by peroxisome proliferator-activated receptor γ (PPARγ), which increases intracellular glucose availability, is identified as a causal mechanism promoting enhanced bacterial survival in AAMs. Glucose uptake was crucial for increased replication of B. abortus in AAMs, and for chronic infection, as inactivation of the bacterial glucose transporter gluP reduced both intracellular survival in AAMs and persistence in mice. Thus, a shift in intracellular nutrient availability induced by PPARγ promotes chronic persistence of B. abortus within AAMs, and targeting this pathway may aid in eradicating chronic infection. PMID:23954155

  5. Reduced peroxisomal citrate synthase activity increases substrate availability for polyhydroxyalkanoate biosynthesis in plant peroxisomes.

    PubMed

    Tilbrook, Kimberley; Poirier, Yves; Gebbie, Leigh; Schenk, Peer M; McQualter, Richard B; Brumbley, Stevens M

    2014-10-01

    Polyhydroxyalkanoates (PHAs) are bacterial carbon storage polymers used as renewable, biodegradable plastics. PHA production in plants may be a way to reduce industrial PHA production costs. We recently demonstrated a promising level of peroxisomal PHA production in the high biomass crop species sugarcane. However, further production strategies are needed to boost PHA accumulation closer to commercial targets. Through exogenous fatty acid feeding of Arabidopsis thaliana plants that contain peroxisome-targeted PhaA, PhaB and PhaC enzymes from Cupriavidus necator, we show here that the availability of substrates derived from the β-oxidation cycle limits peroxisomal polyhydroxybutyrate (PHB) biosynthesis. Knockdown of peroxisomal citrate synthase activity using artificial microRNA increased PHB production levels approximately threefold. This work demonstrates that reduction of peroxisomal citrate synthase activity may be a valid metabolic engineering strategy for increasing PHA production in other plant species. PMID:24944109

  6. Synaptic Proteins In Schizophrenia Hippocampus Indicate Increased Neuronal Activity in CA3

    PubMed Central

    Li, Wei; Ghose, Subroto; Gleason, Kelly; Begovic’, Anita; Perez, Jessica; Bartko, John; Russo, Scott; Wagner, Anthony D.; Selemon, Lynn; Tamminga, Carol A.

    2015-01-01

    In schizophrenia, hippocampal perfusion is increased and declarative memory function is degraded. Based on a model of hippocampal dysfunction in schizophrenic psychosis, we postulated increased NMDA receptor signaling in CA3. Here we demonstrate that the GluN2B-containing NMDA receptors (GluN2B/GluN1) and its associated postsynaptic membrane protein PSD95 are both increased in human hippocampal CA3 from schizophrenia cases, but not in CA1 tissue. Quantitative analyses of Golgi-stained hippocampal neurons show an increase in spine density on CA3 pyramidal cell apical dendrites (stratum radiatum) and an increase in the number of thorny excrescences. AMPA receptor subunit proteins are not altered in CA3 or CA1 subfields, nor are several additional related signaling proteins. These hippocampal data are consistent with increased excitatory signaling in CA3 and/or with an elevation in silent synapses in CA3, a state which may contribute to development of long term potentiation with subsequent stimulation and ‘un-silencing’. These changes are plausibly associated with increased associational activity in CA3, degraded declarative memory function and with psychotic manifestations in schizophrenia. The influence of these hyperactive hippocampal projections onto targets in limbic neocortex could contribute to components of schizophrenia manifestations in other cerebral regions. PMID:25585032

  7. Severe Impingement of Lumbar Disc Replacements Increases the Functional Biological Activity of Polyethylene Wear Debris

    PubMed Central

    Baxter, Ryan M.; MacDonald, Daniel W.; Kurtz, Steven M.; Steinbeck, Marla J.

    2013-01-01

    Background: Wear, oxidation, and particularly rim impingement damage of ultra-high molecular weight polyethylene total disc replacement components have been observed following surgical revision. However, neither in vitro testing nor retrieval-based evidence has shown the effect(s) of impingement on the characteristics of polyethylene wear debris. Thus, we sought to determine (1) differences in polyethylene particle size, shape, number, or biological activity that correspond to mild or severe rim impingement and (2) in an analysis of all total disc replacements, regardless of impingement classification, whether there are correlations between the extent of regional damage and the characteristics of polyethylene wear debris. Methods: The extent of dome and rim damage was characterized for eleven retrieved polyethylene cores obtained at revision surgery after an average duration of implantation of 9.7 years (range, 4.6 to 16.1 years). Polyethylene wear debris was isolated from periprosthetic tissues with use of nitric acid and was imaged with use of environmental scanning electron microscopy. Subsequently, particle size, shape, number, biological activity, and chronic inflammation scores were determined. Results: Grouping of particles by size ranges that represented high biological relevance (<0.1 to 1-μm particles), intermediate biological relevance (1 to 10-μm particles), and low biological relevance (>10-μm particles) revealed an increased volume fraction of particles in the <0.1 to 1-μm and 1 to 10-μm size ranges in the mild-impingement cohort as compared with the severe-impingement cohort. The increased volume fractions resulted in a higher specific biological activity per unit particle volume in the mild-impingement cohort than in the severe-impingement cohort. However, functional biological activity, which is normalized by particle volume (mm3/g of tissue), was significantly higher in the severe-impingement cohort. This increase was due to a larger volume

  8. Activation of calcium-sensing receptor increases TRPC3 expression in rat cardiomyocytes

    SciTech Connect

    Feng, Shan-Li; Sun, Ming-Rui; Li, Ting-Ting; Yin, Xin; Xu, Chang-Qing; Sun, Yi-Hua

    2011-03-11

    Research highlights: {yields} Calcium-sensing receptor (CaR) activation stimulates TRP channels. {yields} CaR promoted transient receptor potential C3 (TRPC3) expression. {yields} Adult rat ventricular myocytes display capacitative calcium entry (CCE), which was operated by TRPCs. {yields} TRPC channels activation induced by CaR activator sustained the increased [Ca{sup 2+}]{sub i} to evoke cardiomyocytes apoptosis. -- Abstract: Transient receptor potential (TRP) channels are expressed in cardiomyocytes, which gate a type of influx of extracellular calcium, the capacitative calcium entry. TRP channels play a role in mediating Ca{sup 2+} overload in the heart. Calcium-sensing receptors (CaR) are also expressed in rat cardiac tissue and promote the apoptosis of cardiomyocytes by Ca{sup 2+} overload. However, data about the link between CaR and TRP channels in rat heart are few. In this study, reverse transcriptase polymerase chain reaction (RT-PCR) and Western blotting were used to examine the expression of the TRP canonical proteins TRPC1 and TRPC3 in adult and neonatal rat cardiomyocytes. Laser scan confocal microscopy was used to detect intracellular [Ca{sup 2+}]{sub i} levels in isolated adult rat ventricular myocytes. The results showed that, in adult rat cardiomyocytes, the depletion of Ca{sup 2+} stores in the endoplasmic/sarcoplasmic reticulum (ER/SR) by thapsigargin induced a transient increase in [Ca{sup 2+}]{sub i} in the absence of [Ca{sup 2+}]{sub o} and the subsequent restoration of [Ca{sup 2+}]{sub o} sustained the increased [Ca{sup 2+}]{sub i} for a few minutes, whereas, the persisting elevation of [Ca{sup 2+}]{sub i} was reduced in the presence of the TRPC inhibitor SKF96365. The stimulation of CaR by its activator gadolinium chloride (GdCl{sub 3}) or spermine also resulted in the same effect and the duration of [Ca{sup 2+}]{sub i} increase was also shortened in the absence of [Ca{sup 2+}]{sub o}. In adult and neonatal rat cardiomyocytes, GdCl{sub 3

  9. Increased Brain Activation for Dual Tasking with 70-Days Head-Down Bed Rest.

    PubMed

    Yuan, Peng; Koppelmans, Vincent; Reuter-Lorenz, Patricia A; De Dios, Yiri E; Gadd, Nichole E; Wood, Scott J; Riascos, Roy; Kofman, Igor S; Bloomberg, Jacob J; Mulavara, Ajitkumar P; Seidler, Rachael D

    2016-01-01

    Head-down tilt bed rest (HDBR) has been used as a spaceflight analog to simulate the effects of microgravity exposure on human physiology, sensorimotor function, and cognition on Earth. Previous studies have reported that concurrent performance of motor and cognitive tasks can be impaired during space missions. Understanding the consequences of HDBR for neural control of dual tasking may possibly provide insight into neural efficiency during spaceflight. In the current study, we evaluated how dual task performance and the underlying brain activation changed as a function of HDBR. Eighteen healthy men participated in this study. They remained continuously in the 6° head-down tilt position for 70 days. Functional MRI for bimanual finger tapping was acquired during both single task and dual task conditions, and repeated at 7 time points pre-, during- and post-HDBR. Another 12 healthy males participated as controls who did not undergo HDBR. A widely distributed network involving the frontal, parietal, cingulate, temporal, and occipital cortices exhibited increased activation for dual tasking and increased activation differences between dual and single task conditions during HDBR relative to pre- or post-HDBR. This HDBR-related brain activation increase for dual tasking implies that more neurocognitive control is needed for dual task execution during HDBR compared to pre- and post-HDBR. We observed a positive correlation between pre-to-post HDBR changes in dual-task cost of reaction time and pre-to-post HDBR change in dual-task cost of brain activation in several cerebral and cerebellar regions. These findings could be predictive of changes in dual task processing during spaceflight. PMID:27601982

  10. Phenylbutyrate increases pyruvate dehydrogenase complex activity in cells harboring a variety of defects

    PubMed Central

    Ferriero, Rosa; Boutron, Audrey; Brivet, Michele; Kerr, Douglas; Morava, Eva; Rodenburg, Richard J; Bonafé, Luisa; Baumgartner, Matthias R; Anikster, Yair; Braverman, Nancy E; Brunetti-Pierri, Nicola

    2014-01-01

    Objective Deficiency of pyruvate dehydrogenase complex (PDHC) is the most common genetic disorder leading to lactic acidosis. PDHC deficiency is genetically heterogenous and most patients have defects in the X-linked E1-α gene but defects in the other components of the complex encoded by PDHB, PDHX, DLAT, DLD genes or in the regulatory enzyme encoded by PDP1 have also been found. Phenylbutyrate enhances PDHC enzymatic activity in vitro and in vivo by increasing the proportion of unphosphorylated enzyme through inhibition of pyruvate dehydrogenase kinases and thus, has potential for therapy of patients with PDHC deficiency. In the present study, we investigated response to phenylbutyrate of multiple cell lines harboring all known gene defects resulting in PDHC deficiency. Methods Fibroblasts of patients with PDHC deficiency were studied for their enzyme activity at baseline and following phenylbutyrate incubation. Drug responses were correlated with genotypes and protein levels by Western blotting. Results Large deletions affecting PDHA1 that result in lack of detectable protein were unresponsive to phenylbutyrate, whereas increased PDHC activity was detected in most fibroblasts harboring PDHA1 missense mutations. Mutations affecting the R349-α residue were directed to proteasome degradation and were consistently unresponsive to short-time drug incubation but longer incubation resulted in increased levels of enzyme activity and protein that may be due to an additional effect of phenylbutyrate as a molecular chaperone. Interpretation PDHC enzyme activity was enhanced by phenylbutyrate in cells harboring missense mutations in PDHB, PDHX, DLAT, DLD, and PDP1 genes. In the prospect of a clinical trial, the results of this study may allow prediction of in vivo response in patients with PDHC deficiency harboring a wide spectrum of molecular defects. PMID:25356417

  11. Increased Telomerase Activity and Vitamin D Supplementation in Overweight African Americans

    PubMed Central

    Zhu, Haidong; Guo, Dehuang; Li, Ke; Pedersen-White, Jennifer; Stallmann-Jorgensen, Inger Susanne; Huang, Ying; Parikh, Samip; Liu, Kebin; Dong, Yanbin

    2013-01-01

    Objective We aimed to investigate whether vitamin D supplementation modulates peripheral blood mononuclear cell telomerase activity in overweight African Americans. Design A double blind, randomized, and placebo-controlled clinical trial (#NCT01141192) was recently conducted. Subjects and methods African American adults were randomly assigned to either the placebo, or the vitamin D group (60,000 IU/month [equivalent to ~2,000 IU/day] oral vitamin D3 supplementation). Fresh peripheral blood mononuclear cells (PBMC) were collected from 37 subjects (18 in the placebo group and 19 in the vitamin D group) both at baseline and 16 weeks. PBMC telomerase activity was measured by the telomeric repeat amplification protocol. Results Serum 25 hydroxyvitamin D levels increased from 40.7±15.7 nmol/L at baseline to 48.1±17.5 nmol/L at posttest (p=0.004) in the placebo group, and from 35.4±11.3 nmol/L at baseline to 103.7±31.5 nmol/L posttests (p<0.0001) in the vitamin D group. In the vitamin D group, PBMC telomerase activity increased by 19.2% from baseline (1.56±0.29 AU) to posttest (1.86±0.42 AU, p<0.0001). The significance persisted after controlling for age, sex and body mass index (p=0.039). PBMC telomerase activity in the placebo group did not change from baseline (1.43±0.26 AU) to posttest (1.46±0.27 AU, p=0.157). Conclusion Vitamin D supplementation significantly increased PBMC telomerase activity in overweight African Americans. Our data suggest that vitamin D may improve telomere maintenance and prevent cell senescence and counteract obesity-induced acceleration of cellular aging. PMID:21986705

  12. Increased Brain Activation for Dual Tasking with 70-Days Head-Down Bed Rest

    PubMed Central

    Yuan, Peng; Koppelmans, Vincent; Reuter-Lorenz, Patricia A.; De Dios, Yiri E.; Gadd, Nichole E.; Wood, Scott J.; Riascos, Roy; Kofman, Igor S.; Bloomberg, Jacob J.; Mulavara, Ajitkumar P.; Seidler, Rachael D.

    2016-01-01

    Head-down tilt bed rest (HDBR) has been used as a spaceflight analog to simulate the effects of microgravity exposure on human physiology, sensorimotor function, and cognition on Earth. Previous studies have reported that concurrent performance of motor and cognitive tasks can be impaired during space missions. Understanding the consequences of HDBR for neural control of dual tasking may possibly provide insight into neural efficiency during spaceflight. In the current study, we evaluated how dual task performance and the underlying brain activation changed as a function of HDBR. Eighteen healthy men participated in this study. They remained continuously in the 6° head-down tilt position for 70 days. Functional MRI for bimanual finger tapping was acquired during both single task and dual task conditions, and repeated at 7 time points pre-, during- and post-HDBR. Another 12 healthy males participated as controls who did not undergo HDBR. A widely distributed network involving the frontal, parietal, cingulate, temporal, and occipital cortices exhibited increased activation for dual tasking and increased activation differences between dual and single task conditions during HDBR relative to pre- or post-HDBR. This HDBR-related brain activation increase for dual tasking implies that more neurocognitive control is needed for dual task execution during HDBR compared to pre- and post-HDBR. We observed a positive correlation between pre-to-post HDBR changes in dual-task cost of reaction time and pre-to-post HDBR change in dual-task cost of brain activation in several cerebral and cerebellar regions. These findings could be predictive of changes in dual task processing during spaceflight. PMID:27601982

  13. Increased Low- and High-Frequency Oscillatory Activity in the Prefrontal Cortex of Fibromyalgia Patients

    PubMed Central

    Lim, Manyoel; Kim, June Sic; Kim, Dajung J.; Chung, Chun Kee

    2016-01-01

    Recent human neuroimaging studies have suggested that fibromyalgia (FM), a chronic widespread pain disorder, exhibits altered thalamic structure and function. Since the thalamus has extensive reciprocal connection with the cortex, structural and functional thalamic alterations in FM might be linked to aberrant thalamocortical oscillation. This study investigated the presence of abnormal brain rhythmicity in low- and high-frequency bands during resting state in patients with FM and their relationship to clinical pain symptom. Spontaneous magnetoencephalography (MEG) activity was recorded in 18 females with FM and 18 age- and sex-matched healthy control (HC) subjects. The most remarkable finding was that FM patients had general increases in theta, beta and gamma power along with a slowing of the dominant alpha peak. Increased spectral powers in the theta-band were primarily localized to the left dorsolateral prefrontal (DLPFC) and orbitofrontal cortex (OFC). Beta and gamma over-activation were localized to insular, primary motor and primary and secondary somatosensory (S2) cortices, as well as the DLPFC and OFC. Furthermore, enhanced high-frequency oscillatory activities in the DLPFC and OFC were associated with higher affective pain scores in patients with FM. Our results demonstrate that FM patients feature enhanced low- and high-frequency oscillatory activity in the brain areas related to cognitive and emotional modulation of pain. Increased low- and high-frequency activity of the prefrontal cortex may contribute to persistent perception of pain in FM. Therapeutic intervention based on manipulating neural oscillation to restore normal thalamocortical rhythmicity may be beneficial to pain relief in FM. PMID:27014041

  14. Intervention to increase physical activity in irritable bowel syndrome shows long-term positive effects

    PubMed Central

    Johannesson, Elisabet; Ringström, Gisela; Abrahamsson, Hasse; Sadik, Riadh

    2015-01-01

    AIM: To assess the long-term effects of physical activity on irritable bowel syndrome (IBS) symptoms and on quality of life, fatigue, depression and anxiety. METHODS: Seventy-six patients from a previous randomized controlled interventional study on increased physical activity in IBS were asked to participate in this long-term follow-up study. The included patients attended one visit in which they filled out questionnaires and they underwent a submaximal cycle ergometer test. The primary end point was the change in the IBS Severity Scoring System (IBS-SSS) at baseline, i.e., before the intervention and at follow-up. The secondary endpoints were changes in quality of life, fatigue, depression and anxiety. RESULTS: A total of 39 [32 women, median age 45 (28-61) years] patients were included in this follow-up. Median follow-up time was 5.2 (range: 3.8-6.2) years. The IBS symptoms were improved compared with baseline [IBS-SSS: 276 (169-360) vs 218 (82-328), P = 0.001]. This was also true for the majority of the dimensions of psychological symptoms such as disease specific quality of life, fatigue, depression and anxiety. The reported time of physical activity during the week before the visit had