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Sample records for hsp70 inhibits aminoglycoside-induced

  1. Cell-surface expression of Hsp70 on hematopoietic cancer cells after inhibition of HDAC activity

    DEFF Research Database (Denmark)

    Jensen, Helle; Andresen, Lars; Hansen, Karen Aagaard

    Heat shock proteins (HSPs) are highly conserved molecules, which support folding of proteins under physiological conditions and mediate protection against lethal damage after various stress stimuli. Five HSP families exist defined by their molecular size (i.e. HSP100, HSP90, HSP70, HSP60, and the......Heat shock proteins (HSPs) are highly conserved molecules, which support folding of proteins under physiological conditions and mediate protection against lethal damage after various stress stimuli. Five HSP families exist defined by their molecular size (i.e. HSP100, HSP90, HSP70, HSP60...... clinically applied reagents, such as alkyl-lysophospholipides, chemotherapeutic agents, and anti-inflammatory reagents, have been found to enhance Hsp70 surface expression on cancer cells. We have found that inhibition of histone deacetylase (HDAC) activity leads to surface expression of Hsp70 on various...... hematopoietic cancer cells, an occurance that was not observed on naïve or activated peripheral blood cells. HDAC-inhibitor mediated Hsp70 surface expression was confined to the apoptotic Annexin V positive cells and blocked by inhibition of apoptosis. Other chemotherapeutic inducers of apoptosis...

  2. Hsp70-GlcNAc-binding activity is released by stress, proteasome inhibition, and protein misfolding

    International Nuclear Information System (INIS)

    Guinez, Celine; Mir, Anne-Marie; Leroy, Yves; Cacan, Rene; Michalski, Jean-Claude; Lefebvre, Tony

    2007-01-01

    Numerous recent works strengthen the idea that the nuclear and cytosolic-specific O-GlcNAc glycosylation protects cells against injuries. We have first investigated O-GlcNAc level and Hsp70-GlcNAc-binding activity (HGBA) behaviour after exposure of HeLa and HepG 2 cells to a wide variety of stresses. O-GlcNAc and HGBA responses were different according to the stress and according to the cell. HGBA was released for almost all stresses, while O-GlcNAc level was modified either upwards or downwards, depending to the stress. Against all expectations, we demonstrated that energy charge did not significantly vary with stress whereas UDP-GlcNAc pools were more dramatically affected even if differences in UDP-GlcNAc contents were not correlated with O-GlcNAc variations suggesting that O-GlcNAc transferase is itself finely regulated during cell injury. Finally, HGBA could be triggered by proteasome inhibition and by L-azetidine-2-carboxylic acid (a proline analogue) incorporation demonstrating that protein misfolding is one of the key-activator of this Hsp70 property

  3. Extracts Obtained from Pterocarpus angolensis DC and Ziziphus mucronata Exhibit Antiplasmodial Activity and Inhibit Heat Shock Protein 70 (Hsp70 Function

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    Tawanda Zininga

    2017-07-01

    Full Text Available Malaria parasites are increasingly becoming resistant to currently used antimalarial therapies, therefore there is an urgent need to expand the arsenal of alternative antimalarial drugs. In addition, it is also important to identify novel antimalarial drug targets. In the current study, extracts of two plants, Pterocarpus angolensis and Ziziphus mucronata were obtained and their antimalarial functions were investigated. Furthermore, we explored the capability of the extracts to inhibit Plasmodium falciparum heat shock protein 70 (Hsp70 function. Heat shock protein 70 (Hsp70 are molecular chaperones whose function is to facilitate protein folding. Plasmodium falciparum the main agent of malaria, expresses two cytosol-localized Hsp70s: PfHsp70-1 and PfHsp70-z. The PfHsp70-z has been reported to be essential for parasite survival, while inhibition of PfHsp70-1 function leads to parasite death. Hence both PfHsp70-1 and PfHsp70-z are potential antimalarial drug targets. Extracts of P. angolensis and Z. mucronata inhibited the basal ATPase and chaperone functions of the two parasite Hsp70s. Furthermore, fractions of P. angolensis and Z. mucronata inhibited P. falciparum 3D7 parasite growth in vitro. The extracts obtained in the current study exhibited antiplasmodial activity as they killed P. falciparum parasites maintained in vitro. In addition, the findings further suggest that some of the compounds in P. angolensis and Z. mucronata may target parasite Hsp70 function.

  4. Heat shock protein (Hsp) 40 mutants inhibit Hsp70 in mammalian cells

    NARCIS (Netherlands)

    Michels, AA; Kanon, B; Bensaude, O; Kampinga, HH

    1999-01-01

    Heat shock protein (Hsp) 70 and Hsp40 expressed in mammalian cells had been previously shown to cooperate in accelerating the reactivation of heat-denatured firefly luciferase (Michels, A. A., Kanon, B., Konings, A. W. T., Ohtsuka, K,, Bensaude, O., and Kampinga, H. H. (1997) J. Biol. Chem. 272,

  5. An RNA aptamer specific to Hsp70-ATP conformation inhibits its ATPase activity independent of Hsp40.

    Science.gov (United States)

    Thirunavukarasu, Deepak; Shi, Hua

    2015-04-01

    The highly conserved and ubiquitous molecular chaperone heat shock protein 70 (Hsp70) plays a critical role in protein homeostasis (proteostasis). Controlled by its ATPase activity, Hsp70 cycles between two conformations, Hsp70-ATP and Hsp70-ADP, to bind and release its substrate. Chemical tools with distinct modes of action, especially those capable of modulating the ATPase activity of Hsp70, are being actively sought after in the mechanistic dissection of this system. Here, we report a conformation-specific RNA aptamer that binds only to Hsp70-ATP but not to Hsp70-ADP. We have refined this aptamer and demonstrated its inhibitory effect on Hsp70's ATPase activity. We have also shown that this inhibitory effect on Hsp70 is independent of its interaction with the Hsp40 co-chaperone. As Hsp70 is increasingly being recognized as a drug target in a number of age related diseases such as neurodegenerative, protein misfolding diseases and cancer, this aptamer is potentially useful in therapeutic applications. Moreover, this work also demonstrates the feasibility of using aptamers to target ATPase activity as a general therapeutic strategy.

  6. Cell-surface expression of Hsp70 on hematopoietic cancer cells after inhibition of HDAC activity

    DEFF Research Database (Denmark)

    Jensen, Helle

    frequently express Hsp70 on their cell surface, whereas the corresponding normal tissues do not. In addition, several clinically applied reagents, such as alkyl-lysophospholipides, chemotherapeutic agents, and anti-inflammatory reagents, have been found to enhance Hsp70 cell surface expression on cancer...

  7. Fisetin, a dietary flavonoid, induces apoptosis of cancer cells by inhibiting HSF1 activity through blocking its binding to the hsp70 promoter.

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    Kim, Joo Ae; Lee, Somyoung; Kim, Da-Eun; Kim, Moonil; Kwon, Byoung-Mog; Han, Dong Cho

    2015-06-01

    Heat shock factor 1 (HSF1) is a transcription factor for heat shock proteins (HSPs) expression that enhances the survival of cancer cells exposed to various stresses. HSF1 knockout suppresses carcinogen-induced cancer induction in mice. Therefore, HSF1 is a promising therapeutic and chemopreventive target. We performed cell-based screening with a natural compound collection and identified fisetin, a dietary flavonoid, as a HSF1 inhibitor. Fisetin abolished heat shock-induced luciferase activity with an IC50 of 14 μM in HCT-116 cancer cells. The treatment of HCT-116 with fisetin inhibited proliferation with a GI50 of 23 μM. When the cells were exposed to heat shock in the presence of fisetin, the induction of HSF1 target proteins, such as HSP70, HSP27 and BAG3 (Bcl-2-associated athanogene domain 3), were inhibited. HSP70/BAG3 complexes protect cancer cells from apoptosis by stabilizing anti-apoptotic Bcl-2 family proteins. The downregulation of HSP70/BAG3 by fisetin significantly reduced the amounts of Bcl-2, Bcl-xL and Mcl-1 proteins, subsequently inducing apoptotic cell death. Chromatin immunoprecipitation assays showed that fisetin inhibited HSF1 activity by blocking the binding of HSF1 to the hsp70 promoter. Intraperitoneal treatment of nude mice with fisetin at 30mg/kg resulted in a 35.7% (P < 0.001) inhibition of tumor growth. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  8. DnaK as Antibiotic Target: Hot Spot Residues Analysis for Differential Inhibition of the Bacterial Protein in Comparison with the Human HSP70.

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    Federica Chiappori

    Full Text Available DnaK, the bacterial homolog of human Hsp70, plays an important role in pathogens survival under stress conditions, like antibiotic therapies. This chaperone sequesters protein aggregates accumulated in bacteria during antibiotic treatment reducing the effect of the cure. Although different classes of DnaK inhibitors have been already designed, they present low specificity. DnaK is highly conserved in prokaryotes (identity 50-70%, which encourages the development of a unique inhibitor for many different bacterial strains. We used the DnaK of Acinetobacter baumannii as representative for our analysis, since it is one of the most important opportunistic human pathogens, exhibits a significant drug resistance and it has the ability to survive in hospital environments. The E.coli DnaK was also included in the analysis as reference structure due to its wide diffusion. Unfortunately, bacterial DnaK and human Hsp70 have an elevated sequence similarity. Therefore, we performed a differential analysis of DnaK and Hsp70 residues to identify hot spots in bacterial proteins that are not present in the human homolog, with the aim of characterizing the key pharmacological features necessary to design selective inhibitors for DnaK. Different conformations of DnaK and Hsp70 bound to known inhibitor-peptides for DnaK, and ineffective for Hsp70, have been analysed by molecular dynamics simulations to identify residues displaying stable and selective interactions with these peptides. Results achieved in this work show that there are some residues that can be used to build selective inhibitors for DnaK, which should be ineffective for the human Hsp70.

  9. Oxygen glucose deprivation post-conditioning protects cortical neurons against oxygen-glucose deprivation injury: role of HSP70 and inhibition of apoptosis.

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    Zhao, Jian-hua; Meng, Xian-li; Zhang, Jian; Li, Yong-li; Li, Yue-juan; Fan, Zhe-ming

    2014-02-01

    In the present study, we examined the effect of oxygen glucose deprivation (OGD) post-conditioning (PostC) on neural cell apoptosis in OGD-PostC model and the protective effect on primary cortical neurons against OGD injury in vitro. Four-h OGD was induced by OGD by using a specialized and humidified chamber. To initiate OGD, culture medium was replaced with de-oxygenated and glucose-free extracellular solution-Locke's medium. After OGD treatment for 4 h, cells were then allowed to recover for 6 h or 20 h. Then lactate dehydrogenase (LDH) release assay, Western blotting and flow cytometry were used to detect cell death, protein levels and apoptotic cells, respectively. For the PostC treatment, three cycles of 15-min OGD, followed by 15 min normal cultivation, were applied immediately after injurious 4-h OGD. Cells were then allowed to recover for 6 h or 20 h, and cell death was assessed by LDH release assay. Apoptotic cells were flow cytometrically evaluated after 4-h OGD, followed by re-oxygenation for 20 h (O4/R20). In addition, Western blotting was used to examine the expression of heat-shock protein 70 (HSP70), Bcl-2 and Bax. The ratio of Bcl-2 expression was (0.44±0.08)% and (0.76±0.10)%, and that of Bax expression was (0.51±0.05)% and (0.39±0.04)%, and that of HSP70 was (0.42±0.031)% and (0.72±0.045)% respectively in OGD group and PostC group. After O4/R6, the rate of neuron death in PostC group and OGD groups was (28.96±3.03)% and (37.02±4.47)%, respectively. Therefore, the PostC treatment could up-regulate the expression of HSP70 and Bcl-2, but down-regulate Bax expression. As compared with OGD group, OGD-induced neuron death and apoptosis were significantly decreased in PostC group (Pneuron death. This neuro-protective effect is likely achieved by anti-apoptotic mechanisms and is associated with over-expression of HSP70.

  10. A novel Hsp70 inhibitor prevents cell intoxication with the actin ADP-ribosylating Clostridium perfringens iota toxin

    Science.gov (United States)

    Ernst, Katharina; Liebscher, Markus; Mathea, Sebastian; Granzhan, Anton; Schmid, Johannes; Popoff, Michel R.; Ihmels, Heiko; Barth, Holger; Schiene-Fischer, Cordelia

    2016-01-01

    Hsp70 family proteins are folding helper proteins involved in a wide variety of cellular pathways. Members of this family interact with key factors in signal transduction, transcription, cell-cycle control, and stress response. Here, we developed the first Hsp70 low molecular weight inhibitor specifically targeting the peptide binding site of human Hsp70. After demonstrating that the inhibitor modulates the Hsp70 function in the cell, we used the inhibitor to show for the first time that the stress-inducible chaperone Hsp70 functions as molecular component for entry of a bacterial protein toxin into mammalian cells. Pharmacological inhibition of Hsp70 protected cells from intoxication with the binary actin ADP-ribosylating iota toxin from Clostridium perfringens, the prototype of a family of enterotoxins from pathogenic Clostridia and inhibited translocation of its enzyme component across cell membranes into the cytosol. This finding offers a starting point for novel therapeutic strategies against certain bacterial toxins. PMID:26839186

  11. Imbalance of Hsp70 family variants fosters tau accumulation.

    Science.gov (United States)

    Jinwal, Umesh K; Akoury, Elias; Abisambra, Jose F; O'Leary, John C; Thompson, Andrea D; Blair, Laura J; Jin, Ying; Bacon, Justin; Nordhues, Bryce A; Cockman, Matthew; Zhang, Juan; Li, Pengfei; Zhang, Bo; Borysov, Sergiy; Uversky, Vladimir N; Biernat, Jacek; Mandelkow, Eckhard; Gestwicki, Jason E; Zweckstetter, Markus; Dickey, Chad A

    2013-04-01

    Dysfunctional tau accumulation is a major contributing factor in tauopathies, and the heat-shock protein 70 (Hsp70) seems to play an important role in this accumulation. Several reports suggest that Hsp70 proteins can cause tau degradation to be accelerated or slowed, but how these opposing activities are controlled is unclear. Here we demonstrate that highly homologous variants in the Hsp70 family can have opposing effects on tau clearance kinetics. When overexpressed in a tetracycline (Tet)-based protein chase model, constitutive heat shock cognate 70 (Hsc70) and inducible Hsp72 slowed or accelerated tau clearance, respectively. Tau synergized with Hsc70, but not Hsp72, to promote microtubule assembly at nearly twice the rate of either Hsp70 homologue in reconstituted, ATP-regenerating Xenopus extracts supplemented with rhodamine-labeled tubulin and human recombinant Hsp72 and Hsc70. Nuclear magnetic resonance spectroscopy with human recombinant protein revealed that Hsp72 had greater affinity for tau than Hsc70 (I/I0 ratio difference of 0.3), but Hsc70 was 30 times more abundant than Hsp72 in human and mouse brain tissue. This indicates that the predominant Hsp70 variant in the brain is Hsc70, suggesting that the brain environment primarily supports slower tau clearance. Despite its capacity to clear tau, Hsp72 was not induced in the Alzheimer's disease brain, suggesting a mechanism for age-associated onset of the disease. Through the use of chimeras that blended the domains of Hsp72 and Hsc70, we determined that the reason for these differences between Hsc70 and Hsp72 with regard to tau clearance kinetics lies within their C-terminal domains, which are essential for their interactions with substrates and cochaperones. Hsp72 but not Hsc70 in the presence of tau was able to recruit the cochaperone ubiquitin ligase CHIP, which is known to facilitate the ubiquitination of tau, describing a possible mechanism of how the C-termini of these homologous Hsp70 variants

  12. Detection of irradiation-induced, membrane heat shock protein 70 (Hsp70) in mouse tumors using Hsp70 Fab fragment

    International Nuclear Information System (INIS)

    Stangl, Stefan; Themelis, George; Friedrich, Lars; Ntziachristos, Vasilis; Sarantopoulos, Athanasios; Molls, Michael; Skerra, Arne; Multhoff, Gabriele

    2011-01-01

    Background and purpose: The major stress-inducible heat shock protein 70 (Hsp70) is frequently overexpressed in highly aggressive tumors, and elevated intracellular Hsp70 levels mediate protection against apoptosis. Following therapeutic intervention, such as ionizing irradiation, translocation of cytosolic Hsp70 to the plasma membrane is selectively increased in tumor cells and therefore, membrane Hsp70 might serve as a therapy-inducible, tumor-specific target structure. Materials and methods: Based on the IgG1 mouse monoclonal antibody (mAb) cmHsp70.1, we produced the Hsp70-specific recombinant Fab fragment (Hsp70 Fab), as an imaging tool for the detection of membrane Hsp70 positive tumor cells in vitro and in vivo. Results: The binding characteristics of Hsp70 Fab towards mouse colon (CT26) and pancreatic (1048) carcinoma cells at 4 deg. C were comparable to that of cmHsp70.1 mAb, as determined by flow cytometry. Following a temperature shift to 37 deg. C, Hsp70 Fab rapidly translocates into subcellular vesicles of mouse tumor cells. Furthermore, in tumor-bearing mice Cy5.5-conjugated Hsp70 Fab, but not unrelated IN-1 control Fab fragment (IN-1 ctrl Fab), gradually accumulates in CT26 tumors between 12 and 55 h after i.v. injection. Conclusions: In summary, the Hsp70 Fab provides an innovative, low immunogenic tool for imaging of membrane Hsp70 positive tumors, in vivo.

  13. Hsp70 stabilizes lysosomes and reverts Niemann-Pick disease-associated lysosomal pathology

    DEFF Research Database (Denmark)

    Kirkegaard, Thomas; Roth, Anke G; Petersen, Nikolaj H T

    2010-01-01

    Heat shock protein 70 (Hsp70) is an evolutionarily highly conserved molecular chaperone that promotes the survival of stressed cells by inhibiting lysosomal membrane permeabilization, a hallmark of stress-induced cell death. Clues to its molecular mechanism of action may lay in the recently...... reported stress- and cancer-associated translocation of a small portion of Hsp70 to the lysosomal compartment. Here we show that Hsp70 stabilizes lysosomes by binding to an endolysosomal anionic phospholipid bis(monoacylglycero)phosphate (BMP), an essential co-factor for lysosomal sphingomyelin metabolism......-is also associated with a marked decrease in lysosomal stability, and this phenotype can be effectively corrected by treatment with recombinant Hsp70. Taken together, these data open exciting possibilities for the development of new treatments for lysosomal storage disorders and cancer with compounds...

  14. Reduced Hsp70 and Glutamine in Pediatric Severe Malaria Anemia

    DEFF Research Database (Denmark)

    Kempaiah, Prakasha; Dokladny, Karol; Karim, Zachary

    2016-01-01

    by decreased HSPA1A, a heat shock protein (Hsp) 70 coding gene. Hsp70 is a ubiquitous chaperone that regulates Nuclear Factor-kappa B (NF-κB) signaling and production of pro-inflammatory cytokines known to be important in malaria pathogenesis (e.g., IL-1β, IL-6 and TNF-α). Since the role of host Hsp70...... in malaria pathogenesis is unexplored, we investigated Hsp70 and molecular pathways in children with SMA. Validation experiments revealed that leukocytic HSP70 transcripts were reduced in SMA relative to non-severe malaria, and that intraleukocytic hemozoin (PfHz) was associated with lower HSP70. HSP70...... was correlated with reticulocyte production and Hb. Since glutamine (Gln) up-regulates Hsp70, modulates NF-κB activation, and attenuates over-expression of pro-inflammatory cytokines, circulating Gln was measured in children with malaria. Reduced Gln was associated with increased risk of developing SMA...

  15. The Human Escort Protein Hep Binds to the ATPase Domain of Mitochondrial Hsp70 and Regulates ATP Hydrolysis*

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    Zhai, Peng; Stanworth, Crystal; Liu, Shirley; Silberg, Jonathan J.

    2008-01-01

    Hsp70 escort proteins (Hep) have been implicated as essential for maintaining the function of yeast mitochondrial hsp70 molecular chaperones (mtHsp70), but the role that escort proteins play in regulating mammalian chaperone folding and function has not been established. We present evidence that human mtHsp70 exhibits limited solubility due to aggregation mediated by its ATPase domain and show that human Hep directly enhances chaperone solubility through interactions with this domain. In the absence of Hep, mtHsp70 was insoluble when expressed in Escherichia coli, as was its isolated ATPase domain and a chimera having this domain fused to the peptide-binding domain of HscA, a soluble monomeric chaperone. In contrast, these proteins all exhibited increased solubility when expressed in the presence of Hep. In vitro studies further revealed that purified Hep regulates the interaction of mtHsp70 with nucleotides. Full-length mtHsp70 exhibited slow intrinsic ATP hydrolysis activity (6.8 ± 0.2 × 10-4 s-1) at 25 °C, which was stimulated up to 49-fold by Hep. Hep also stimulated the activity of the isolated ATPase domain, albeit to a lower maximal extent (11.5-fold). In addition, gel-filtration studies showed that formation of chaperone-escort protein complexes inhibited mtHsp70 self-association, and they revealed that Hep binding to full-length mtHsp70 and its isolated ATPase domain is strongest in the absence of nucleotides. These findings provide evidence that metazoan escort proteins regulate the catalytic activity and solubility of their cognate chaperones, and they indicate that both forms of regulation arise from interactions with the mtHsp70 ATPase domain. PMID:18632665

  16. The human escort protein Hep binds to the ATPase domain of mitochondrial hsp70 and regulates ATP hydrolysis.

    Science.gov (United States)

    Zhai, Peng; Stanworth, Crystal; Liu, Shirley; Silberg, Jonathan J

    2008-09-19

    Hsp70 escort proteins (Hep) have been implicated as essential for maintaining the function of yeast mitochondrial hsp70 molecular chaperones (mtHsp70), but the role that escort proteins play in regulating mammalian chaperone folding and function has not been established. We present evidence that human mtHsp70 exhibits limited solubility due to aggregation mediated by its ATPase domain and show that human Hep directly enhances chaperone solubility through interactions with this domain. In the absence of Hep, mtHsp70 was insoluble when expressed in Escherichia coli, as was its isolated ATPase domain and a chimera having this domain fused to the peptide-binding domain of HscA, a soluble monomeric chaperone. In contrast, these proteins all exhibited increased solubility when expressed in the presence of Hep. In vitro studies further revealed that purified Hep regulates the interaction of mtHsp70 with nucleotides. Full-length mtHsp70 exhibited slow intrinsic ATP hydrolysis activity (6.8+/-0.2 x 10(-4) s(-1)) at 25 degrees C, which was stimulated up to 49-fold by Hep. Hep also stimulated the activity of the isolated ATPase domain, albeit to a lower maximal extent (11.5-fold). In addition, gel-filtration studies showed that formation of chaperone-escort protein complexes inhibited mtHsp70 self-association, and they revealed that Hep binding to full-length mtHsp70 and its isolated ATPase domain is strongest in the absence of nucleotides. These findings provide evidence that metazoan escort proteins regulate the catalytic activity and solubility of their cognate chaperones, and they indicate that both forms of regulation arise from interactions with the mtHsp70 ATPase domain.

  17. Hsp70/J-protein machinery from Glossina morsitans morsitans, vector of African trypanosomiasis.

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    Stephen J Bentley

    Full Text Available Tsetse flies (Glossina spp. are the sole vectors of the protozoan parasites of the genus Trypanosoma, the causative agents of African Trypanosomiasis. Species of Glossina differ in vector competence and Glossina morsitans morsitans is associated with transmission of Trypanosoma brucei rhodesiense, which causes an acute and often fatal form of African Trypanosomiasis. Heat shock proteins are evolutionarily conserved proteins that play critical roles in proteostasis. The activity of heat shock protein 70 (Hsp70 is regulated by interactions with its J-protein (Hsp40 co-chaperones. Inhibition of these interactions are emerging as potential therapeutic targets. The assembly and annotation of the G. m. morsitans genome provided a platform to identify and characterize the Hsp70s and J-proteins, and carry out an evolutionary comparison to its well-studied eukaryotic counterparts, Drosophila melanogaster and Homo sapiens, as well as Stomoxys calcitrans, a comparator species. In our study, we identified 9 putative Hsp70 proteins and 37 putative J-proteins in G. m. morsitans. Phylogenetic analyses revealed three evolutionarily distinct groups of Hsp70s, with a closer relationship to orthologues from its blood-feeding dipteran relative Stomoxys calcitrans. G. m. morsitans also lacked the high number of heat inducible Hsp70s found in D. melanogaster. The potential localisations, functions, domain organisations and Hsp70/J-protein partnerships were also identified. A greater understanding of the heat shock 70 (Hsp70 and J-protein (Hsp40 families in G. m. morsitans could enhance our understanding of the cell biology of the tsetse fly.

  18. The Complex Function of Hsp70 in Metastatic Cancer

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    Juhasz, Kata; Lipp, Anna-Maria; Nimmervoll, Benedikt; Sonnleitner, Alois; Hesse, Jan; Haselgruebler, Thomas; Balogi, Zsolt, E-mail: zsolt.balogi@cbl.at [Center for Advanced Bioanalysis GmbH, Gruberstr. 40-42, A-4020 Linz (Austria)

    2013-12-20

    Elevated expression of the inducible heat shock protein 70 (Hsp70) is known to correlate with poor prognosis in many cancers. Hsp70 confers survival advantage as well as resistance to chemotherapeutic agents, and promotes tumor cell invasion. At the same time, tumor-derived extracellular Hsp70 has been recognized as a “chaperokine”, activating antitumor immunity. In this review we discuss localization dependent functions of Hsp70 in the context of invasive cancer. Understanding the molecular principles of metastasis formation steps, as well as interactions of the tumor cells with the microenvironment and the immune system is essential for fighting metastatic cancer. Although Hsp70 has been implicated in different steps of the metastatic process, the exact mechanisms of its action remain to be explored. Known and potential functions of Hsp70 in controlling or modulating of invasion and metastasis are discussed.

  19. Accumulation of hepatic Hsp70 and plasma cortisol in Oreochromis ...

    African Journals Online (AJOL)

    The hepatic isoforms Hsp70, Hsp74 and Hsp76 were identified and quantified from copper exposures. Long-term DDT exposure did not result in significant induction of hepatic Hsp70. An increase in plasma cortisol concentration was associated with a decrease in heat shock protein accumulation after cadmium exposure, ...

  20. Imaging of Hsp70-positive tumors with cmHsp70.1 antibody-conjugated gold nanoparticles

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    Gehrmann MK

    2015-09-01

    Full Text Available Mathias K Gehrmann,1 Melanie A Kimm,2 Stefan Stangl,1 Thomas E Schmid,1 Peter B Noël,2 Ernst J Rummeny,2 Gabriele Multhoff11Department of Radiation Oncology, 2Department of Diagnostic and Interventional Radiology, Klinikum rechts der Isar, Technische Universität München, Munich, GermanyAbstract: Real-time imaging of small tumors is still one of the challenges in cancer diagnosis, prognosis, and monitoring of clinical outcome. Targeting novel biomarkers that are selectively expressed on a large variety of different tumors but not normal cells has the potential to improve the imaging capacity of existing methods such as computed tomography. Herein, we present a novel technique using cmHsp70.1 monoclonal antibody-conjugated spherical gold nanoparticles for quantification of the targeted uptake of gold nanoparticles into membrane Hsp70-positive tumor cells. Upon binding, cmHsp70.1-conjugated gold nanoparticles but not nanoparticles coupled to an isotype-matched IgG1 antibody or empty nanoparticles are rapidly taken up by highly malignant Hsp70 membrane-positive mouse tumor cells. After 24 hours, the cmHsp70.1-conjugated gold nanoparticles are found to be enriched in the perinuclear region. Specificity for membrane Hsp70 was shown by using an Hsp70 knockout tumor cell system. Toxic side effects of the cmHsp70.1-conjugated nanoparticles are not observed at a concentration of 1–10 µg/mL. Experiments are ongoing to evaluate whether cmHsp70.1 antibody-conjugated gold nanoparticles are suitable for the detection of membrane-Hsp70-positive tumors in vivo.Keywords: heat shock protein 70, tumor biomarker, theranostics, multimodal CT, multispectral CT, k-edge

  1. Heat shock proteins (Hsp 70) response is not systematic to cell stress

    International Nuclear Information System (INIS)

    Hassen, Wafa; Ayed-Boussema, Imen; Bouslimi, Amel; Bacha, Hassen

    2007-01-01

    Ochratoxin A (OTA) is a mycotoxin routinely detected in improperly stored animal and human food supplies as well as in human sera worldwide. OTA has multiple toxic effects; however, the most prominent is nephrotoxicity. Thus, OTA is involved in the pathogenesis of human nephropathy in Balkan areas. In this study, we address the question of the appropriate functioning of the basal cellular defense mechanisms, after exposure to OTA, which, up to now, has not been investigated satisfactorily. In this context, we have monitored the effect of OTA on (i) the inhibition of cell viability, (ii) the oxidative damage using the GSH depletion, (iii) the inhibition of protein synthesis through the incorporation of [ 3 H] Leucine and (iv) the induction of Hsp 70 gene expression as a parameter of cytotoxicity, oxidative damage and particularly as a protective and adaptative response. This study was conducted using the Human Hep G2 hepatocytes and monkey kidney Vero cells under exposure conditions ranging from non-cytotoxic to sub-lethal. Our results clearly showed that OTA inhibits cell proliferation, strongly reduces protein synthesis and induces the decrease of GSH in concentration-dependent manner in both Hep G2 and Vero cells. However, although cytotoxicity and oxidative damage (main inducers of Hsp expression) occur, no change was observed in Hsp 70 level under the multiple tested conditions. Inhibition of protein synthesis could not explain the absence of Hsp 70 response since concentrations, which did not influence protein synthesis, also failed to display the expected Hsp 70 response. Our data are consistent with recently published reports where considerable differences were noticed in the ability of relevant toxicants to induce Hsp. These results raised doubt about the universal character of Hsp induction which seems to be more complex than originally envisioned. It could be concluded that Hsp 70 induction is not systematic to cell stress

  2. Targeting HSP70 and GRP78 in canine osteosarcoma cells in combination with doxorubicin chemotherapy.

    Science.gov (United States)

    Asling, Jonathan; Morrison, Jodi; Mutsaers, Anthony J

    2016-11-01

    Heat shock proteins (HSPs) are molecular chaperones subdivided into several families based on their molecular weight. Due to their cytoprotective roles, these proteins may help protect cancer cells against chemotherapy-induced cell death. Investigation into the biologic activity of HSPs in a variety of cancers including primary bone tumors, such as osteosarcoma (OSA), is of great interest. Both human and canine OSA tumor samples have aberrant production of HSP70. This study assessed the response of canine OSA cells to inhibition of HSP70 and GRP78 by the ATP-mimetic VER-155008 and whether this treatment strategy could sensitize cells to doxorubicin chemotherapy. Single-agent VER-155008 treatment decreased cellular viability and clonogenic survival and increased apoptosis in canine OSA cell lines. However, combination schedules with doxorubicin after pretreatment with VER-155008 did not improve inhibition of cellular viability, apoptosis, or clonogenic survival. Treatment with VER-155008 prior to chemotherapy resulted in an upregulation of target proteins HSP70 and GRP78 in addition to the co-chaperone proteins Herp, C/EBP homologous transcription protein (CHOP), and BAG-1. The increased GRP78 was more cytoplasmic in location compared to untreated cells. Single-agent treatment also revealed a dose-dependent reduction in activated and total Akt. Based on these results, targeting GRP78 and HSP70 may have biologic activity in canine osteosarcoma. Further studies are required to determine if and how this strategy may impact the response of osteosarcoma cells to chemotherapy.

  3. IL-10 is significantly involved in HSP70-regulation of experimental subretinal fibrosis.

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    Yang Yang

    Full Text Available Subretinal fibrosis is directly related to severe visual loss, especially if occurs in the macula, and is frequently observed in advanced age-related macular degeneration and other refractory eye disorders such as diabetic retinopathy and uveitis. In this study, we analyzed the immunosuppressive mechanism of subretinal fibrosis using the novel animal model recently demonstrated. Both TLR2 and TLR4 deficient mice showed significant enlargement of subretinal fibrotic area as compared with wild-type mice. A single intraocular administration of heat shock protein 70 (HSP70, which is an endogenous ligand for TLR2 and TLR4, inhibited subretinal fibrosis in wild-type mice but not in TLR2 and TLR4-deficient mice. Additionally, HSP70 induced IL-10 production in eyes from wild-type mice but was impaired in both TLR2- and TLR4-deficient mice, indicating that HSP70-TLR2/TLR4 axis plays an immunomodulatory role in subretinal fibrosis. Thus, these results suggest that HSP70-TLR2/TLR4 axis is a new therapeutic target for subretinal fibrosis due to prognostic CNV.

  4. Plasmodium falciparum Hsp70-z, an Hsp110 homologue, exhibits independent chaperone activity and interacts with Hsp70-1 in a nucleotide-dependent fashion.

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    Zininga, Tawanda; Achilonu, Ikechukwu; Hoppe, Heinrich; Prinsloo, Earl; Dirr, Heini W; Shonhai, Addmore

    2016-05-01

    The role of molecular chaperones, among them heat shock proteins (Hsps), in the development of malaria parasites has been well documented. Hsp70s are molecular chaperones that facilitate protein folding. Hsp70 proteins are composed of an N-terminal nucleotide binding domain (NBD), which confers them with ATPase activity and a C-terminal substrate binding domain (SBD). In the ADP-bound state, Hsp70 possesses high affinity for substrate and releases the folded substrate when it is bound to ATP. The two domains are connected by a conserved linker segment. Hsp110 proteins possess an extended lid segment, a feature that distinguishes them from canonical Hsp70s. Plasmodium falciparum Hsp70-z (PfHsp70-z) is a member of the Hsp110 family of Hsp70-like proteins. PfHsp70-z is essential for survival of malaria parasites and is thought to play an important role as a molecular chaperone and nucleotide exchange factor of its cytosolic canonical Hsp70 counterpart, PfHsp70-1. Unlike PfHsp70-1 whose functions are fairly well established, the structure-function features of PfHsp70-z remain to be fully elucidated. In the current study, we established that PfHsp70-z possesses independent chaperone activity. In fact, PfHsp70-z appears to be marginally more effective in suppressing protein aggregation than its cytosol-localized partner, PfHsp70-1. Furthermore, based on coimmunoaffinity chromatography and surface plasmon resonance analyses, PfHsp70-z associated with PfHsp70-1 in a nucleotide-dependent fashion. Our findings suggest that besides serving as a molecular chaperone, PfHsp70-z could facilitate the nucleotide exchange function of PfHsp70-1. These dual functions explain why it is essential for parasite survival.

  5. Radioresistance of human glioma spheroids and expression of HSP70, p53 and EGFr

    International Nuclear Information System (INIS)

    Fedrigo, Carlos A; Rocha, Adriana B da; Grivicich, Ivana; Schunemann, Daniel P; Chemale, Ivan M; Santos, Daiane dos; Jacovas, Thais; Boschetti, Patryck S; Jotz, Geraldo P; Filho, Aroldo Braga

    2011-01-01

    Radiation therapy is routinely prescribed for high-grade malignant gliomas. However, the efficacy of this therapeutic modality is often limited by the occurrence of radioresistance, reflected as a diminished susceptibility of the irradiated cells to undergo cell death. Thus, cells have evolved an elegant system in response to ionizing radiation induced DNA damage, where p53, Hsp70 and/or EGFr may play an important role in the process. In the present study, we investigated whether the content of p53, Hsp70 and EGFr are associated to glioblastoma (GBM) cell radioresistance. Spheroids from U-87MG and MO59J cell lines as well as spheroids derived from primary culture of tumor tissue of one GBM patient (UGBM1) were irradiated (5, 10 and 20 Gy), their relative radioresistance were established and the p53, Hsp70 and EGFr contents were immunohistochemically determined. Moreover, we investigated whether EGFr-phospho-Akt and EGFr-MEK-ERK pathways can induce GBM radioresistance using inhibitors of activation of ERK (PD098059) and Akt (wortmannin). At 5 Gy irradiation UGBM1 and U-87MG spheroids showed growth inhibition whereas the MO59J spheroid was relatively radioresistant. Overall, no significant changes in p53 and Hsp70 expression were found following 5 Gy irradiation treatment in all spheroids studied. The only difference observed in Hsp70 content was the periphery distribution in MO59J spheroids. However, 5 Gy treatment induced a significant increase on the EGFr levels in MO59J spheroids. Furthermore, treatment with inhibitors of activation of ERK (PD098059) and Akt (wortmannin) leads to radiosensitization of MO59J spheroids. These results indicate that the PI3K-Akt and MEK-ERK pathways triggered by EGFr confer GBM radioresistance

  6. The Exported Chaperone PfHsp70x Is Dispensable for the Plasmodium falciparum Intraerythrocytic Life Cycle.

    Science.gov (United States)

    Cobb, David W; Florentin, Anat; Fierro, Manuel A; Krakowiak, Michelle; Moore, Julie M; Muralidharan, Vasant

    2017-01-01

    needed to combat the deadliest agent of malaria, P. falciparum . An outstanding question in the field is how P. falciparum undertakes the essential process of trafficking its proteins within the host cell. In most organisms, chaperones such as Hsp70 are employed in protein trafficking. Of the Plasmodium species causing human disease, the chaperone PfHsp70x is unique to P. falciparum , and it is the only parasite protein of its kind exported to the host (S. Külzer et al., Cell Microbiol 14:1784-1795, 2012). This has placed PfHsp70x as an ideal target to inhibit protein trafficking and kill the parasite. However, we show that PfHsp70x is not required for export of parasite effectors and it is not essential for parasite survival inside the RBC.

  7. KADAR MDA DAN HSP 70 PADA PLASENTA PENDERITA PREEKLAMPSIA

    Directory of Open Access Journals (Sweden)

    Arleni

    2008-12-01

    Full Text Available The MDA and HSP70 Concentration in Preeclamptic Patient Placenta’s. Objective: Preeclampsia is a disease in pregnancy and characterized by hypertension and proteinuria. Preeclampsia and eclampsia are the most causes of maternal and fetal mortality and morbidity in Indonesia. Placental and systemic oxidative stress caused endothelial cell dysfunction and injury. Placental oxidative stress also linked to fetal growth restriction. HSP70 is essential for cellular recovery, survival and maintenance of homeostasis. The purpose of this study was to compare the MDA, a marker for oxidative stress and HSP70 production in placental of severe preeclampsia, mild preeclampsia and normotensive pregnant women. Placenta were collected after delivery from normotensive pregnancies (N=10, severe preeclampsia (N=10 and mild preeclampsia (N=10. Placenta was cultured in RPMI and 20% FBS, and supernatant were collected in day 3. MDA was measured using spectrophotometer and absorbance read in 530nm. HSP70 was measured using enzyme-linked immunosorbent assay. The mean MDA concentration did not differ significantly between patients with severe preeclampsia (7.13+5.36 nmol/ml and mild preeclampsia (4.82+2.47 nmol/ml when compared with normotensive pregnancies (4.57+2.4 nmol/ml. The mean HSP70 concentration in mild preeclampsia is highest (10.15+12.39 nmo/ml when compared with severe preeclampsia (3.78 +3.07 nmol/ml and normotensive pregnant women (3.76+4.65nmol/ml, but the difference was not significant. Although the difference was not significant, is indicates homeostasis response in mild preclampsia women is relative good. This response was abated in severe preeclampstic women. Although MDA and HSP70 concentration did not differ significantly between groups, however the high HSP70 concentration is indicates homeostasis response relatively good in mild preeclamptic women.

  8. Crystal structures of the ATPase domains of four human Hsp70 isoforms: HSPA1L/Hsp70-hom, HSPA2/Hsp70-2, HSPA6/Hsp70B', and HSPA5/BiP/GRP78.

    Science.gov (United States)

    Wisniewska, Magdalena; Karlberg, Tobias; Lehtiö, Lari; Johansson, Ida; Kotenyova, Tetyana; Moche, Martin; Schüler, Herwig

    2010-01-11

    The 70-kDa heat shock proteins (Hsp70) are chaperones with central roles in processes that involve polypeptide remodeling events. Hsp70 proteins consist of two major functional domains: an N-terminal nucleotide binding domain (NBD) with ATPase activity, and a C-terminal substrate binding domain (SBD). We present the first crystal structures of four human Hsp70 isoforms, those of the NBDs of HSPA1L, HSPA2, HSPA5 and HSPA6. As previously with Hsp70 family members, all four proteins crystallized in a closed cleft conformation, although a slight cleft opening through rotation of subdomain IIB was observed for the HSPA5-ADP complex. The structures presented here support the view that the NBDs of human Hsp70 function by conserved mechanisms and contribute little to isoform specificity, which instead is brought about by the SBDs and by accessory proteins. This article can also be viewed as an enhanced version in which the text of the article is integrated with interactive 3D representations and animated transitions. Please note that a web plugin is required to access this enhanced functionality. Instructions for the installation and use of the web plugin are available in Text S1.

  9. Crystal structures of the ATPase domains of four human Hsp70 isoforms: HSPA1L/Hsp70-hom, HSPA2/Hsp70-2, HSPA6/Hsp70B', and HSPA5/BiP/GRP78.

    Directory of Open Access Journals (Sweden)

    Magdalena Wisniewska

    2010-01-01

    Full Text Available The 70-kDa heat shock proteins (Hsp70 are chaperones with central roles in processes that involve polypeptide remodeling events. Hsp70 proteins consist of two major functional domains: an N-terminal nucleotide binding domain (NBD with ATPase activity, and a C-terminal substrate binding domain (SBD. We present the first crystal structures of four human Hsp70 isoforms, those of the NBDs of HSPA1L, HSPA2, HSPA5 and HSPA6. As previously with Hsp70 family members, all four proteins crystallized in a closed cleft conformation, although a slight cleft opening through rotation of subdomain IIB was observed for the HSPA5-ADP complex. The structures presented here support the view that the NBDs of human Hsp70 function by conserved mechanisms and contribute little to isoform specificity, which instead is brought about by the SBDs and by accessory proteins.This article can also be viewed as an enhanced version in which the text of the article is integrated with interactive 3D representations and animated transitions. Please note that a web plugin is required to access this enhanced functionality. Instructions for the installation and use of the web plugin are available in Text S1.

  10. Albumin stimulates renal tubular inflammation through an HSP70-TLR4 axis in mice with early diabetic nephropathy

    Science.gov (United States)

    Jheng, Huei-Fen; Tsai, Pei-Jane; Chuang, Yi-Lun; Shen, Yi-Ting; Tai, Ting-An; Chen, Wen-Chung; Chou, Chuan-Kai; Ho, Li-Chun; Tang, Ming-Jer; Lai, Kuei-Tai A.; Sung, Junne-Ming; Tsai, Yau-Sheng

    2015-01-01

    ABSTRACT Increased urinary albumin excretion is not simply an aftermath of glomerular injury, but is also involved in the progression of diabetic nephropathy (DN). Whereas Toll-like receptors (TLRs) are incriminated in the renal inflammation of DN, whether and how albumin is involved in the TLR-related renal inflammatory response remains to be clarified. Here, we showed that both TLR2 and TLR4, one of their putative endogenous ligands [heat shock protein 70 (HSP70)] and nuclear factor-κB promoter activity were markedly elevated in the kidneys of diabetic mice. A deficiency of TLR4 but not of TLR2 alleviated albuminuria, tubulointerstitial fibrosis and inflammation induced by diabetes. The protection against renal injury in diabetic Tlr4−/− mice was associated with reduced tubular injuries and preserved cubilin levels, rather than amelioration of glomerular lesions. In vitro studies revealed that albumin, a stronger inducer than high glucose (HG), induced the release of HSP70 from proximal tubular cells. HSP70 blockade ameliorated albumin-induced inflammatory mediators. HSP70 triggered the production of inflammatory mediators in a TLR4-dependent manner. Moreover, HSP70 inhibition in vivo ameliorated diabetes-induced albuminuria, inflammatory response and tubular injury. Finally, we found that individuals with DN had higher levels of TLR4 and HSP70 in the dilated tubules than non-diabetic controls. Thus, activation of the HSP70-TLR4 axis, stimulated at least in part by albumin, in the tubular cell is a newly identified mechanism associated with induction of tubulointerstitial inflammation and aggravation of pre-existing microalbuminuria in the progression of DN. PMID:26398934

  11. Geranylgeranylacetone ameliorates lung ischemia/reperfusion injury by HSP70 and thioredoxin redox system: NF-kB pathway involved.

    Science.gov (United States)

    Cao, Weijun; Li, Manhui; Li, Jianxiong; Li, Chengwei; Xu, Xin; Gu, Weiqing

    2015-06-01

    Geranylgeranylacetone (GGA) has been clinically used as an anti-ulcer drug. In the present study, we explored the protective effects of GGA on lung ischemia/reperfusion injury (IRI) and the underlying mechanism. The results demonstrated that GGA ameliorated the lung biochemical and histological alterations induced by IRI, which was reversed by HSP70 inhibition. To further explore the mechanism of GGA action, we focused on NF-kB and thioredoxin (Trx) redox system. It was shown that GGA induced the HSP70 and Trx-1 expression, NF-kB nuclear translocation and activated thioredoxin reductase (TrxR). The Trx-1 expression and TrxR activity was suppressed by HSP70 and NF-kB inhibition, while the nuclear NF-kB p65 expression was suppressed by HSP70 inhibitor. These results indicated that GGA may protect rat lung against IRI by HSP70 and Trx redox system, in which NF-kB pathway may be involved. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. thermal stress and Hsp70 as selective agents

    Indian Academy of Sciences (India)

    Madhu Sudhan

    starred in an exhaustive list of studies linking its expression to environmental ... genetic stress linked to Hsp70: polyglutamine expansion .... Twenty-five D. melanogaster genes conserved in all twelve Drosophila species (fourth column) possessing conserved ...... like growth factor-1, and vertebral bone mass in men; J. Clin.

  13. Antileukemic activity of the HSP70 inhibitor pifithrin-μ in acute leukemia

    International Nuclear Information System (INIS)

    Kaiser, M; Kühnl, A; Reins, J; Fischer, S; Ortiz-Tanchez, J; Schlee, C; Mochmann, L H; Heesch, S; Benlasfer, O; Hofmann, W-K; Thiel, E; Baldus, C D

    2011-01-01

    Heat shock protein (HSP) 70 is aberrantly expressed in different malignancies and has emerged as a promising new target for anticancer therapy. Here, we analyzed the in vitro antileukemic effects of pifithrin-μ (PFT-μ), an inhibitor of inducible HSP70, in acute myeloid leukemia (AML) and acute lymphoblastic leukemia (ALL) cell lines, as well as in primary AML blasts. PFT-μ significantly inhibited cell viability at low micromolar concentrations in all cell lines tested, with IC50 values ranging from 2.5 to 12.7 μ, and was highly active in primary AML blasts with a median IC50 of 8.9 μ (range 5.7–37.2). Importantly, higher IC50 values were seen in normal hematopoietic cells. In AML and ALL, PFT-μ induced apoptosis and cell cycle arrest in a dose-dependent fashion. PFT-μ also led to an increase of the active form of caspase-3 and reduced the intracellular concentrations of AKT and ERK1/2 in NALM-6 cells. Moreover, PFT-μ enhanced cytotoxicity of cytarabine, 17-(allylamino)-17-desmethoxygeldanamycin, suberoylanilide hydroxamic acid, and sorafenib in NALM-6, TOM-1 and KG-1a cells. This is the first study demonstrating significant antileukemic effects of the HSP70 inhibitor PFT-μ, alone and in combination with different antineoplastic drugs in both AML and ALL. Our results suggest a potential therapeutic role for PFT-μ in acute leukemias

  14. Andrographolide induces degradation of mutant p53 via activation of Hsp70.

    Science.gov (United States)

    Sato, Hirofumi; Hiraki, Masatsugu; Namba, Takushi; Egawa, Noriyuki; Baba, Koichi; Tanaka, Tomokazu; Noshiro, Hirokazu

    2018-05-22

    The tumor suppressor gene p53 encodes a transcription factor that regulates various cellular functions, including DNA repair, apoptosis and cell cycle progression. Approximately half of all human cancers carry mutations in p53 that lead to loss of tumor suppressor function or gain of functions that promote the cancer phenotype. Thus, targeting mutant p53 as an anticancer therapy has attracted considerable attention. In the current study, a small-molecule screen identified andrographlide (ANDRO) as a mutant p53 suppressor. The effects of ANDRO, a small molecule isolated from the Chinese herb Andrographis paniculata, on tumor cells carrying wild-type or mutant p53 were examined. ANDRO suppressed expression of mutant p53, induced expression of the cyclin-dependent kinase inhibitor p21 and pro-apoptotic proteins genes, and inhibited the growth of cancer cells harboring mutant p53. ANDRO also induced expression of the heat-shock protein (Hsp70) and increased binding between Hsp70 and mutant p53 protein, thus promoting proteasomal degradation of p53. These results provide novel insights into the mechanisms regulating the function of mutant p53 and suggest that activation of Hsp70 may be a new strategy for the treatment of cancers harboring mutant p53.

  15. Cytosine deletion at AP2-box region of HSP70 promoter and its ...

    Indian Academy of Sciences (India)

    of thermotolerance in cells (Leung et al. 1996). ... region of HSP70 significantly affected cellular thermotol- erance ... The double PCR-RFLP using ScrFI confirmed the occur- ... suade of HSP70 on defense of proteins related to respiration.

  16. 70 kD stress protein (Hsp70) analysis in living shallow-water benthic foraminifera

    Digital Repository Service at National Institute of Oceanography (India)

    Heinz, P.; Marten, R.A; Linshy, V.N.; Haap, T.; Geslin, E.; Kohler, H-R.

    Hsp70 is a phylogenetically highly conserved protein family present in all eukaryotic organisms tested so far. Its synthesis is induced by proteotoxic stress. The detection of Hsp70 in foraminifera is presented here. We introduce a standard...

  17. The conformational dynamics of the mitochondrial Hsp70 chaperone.

    Science.gov (United States)

    Mapa, Koyeli; Sikor, Martin; Kudryavtsev, Volodymyr; Waegemann, Karin; Kalinin, Stanislav; Seidel, Claus A M; Neupert, Walter; Lamb, Don C; Mokranjac, Dejana

    2010-04-09

    Heat shock proteins 70 (Hsp70) represent a ubiquitous and conserved family of molecular chaperones involved in a plethora of cellular processes. The dynamics of their ATP hydrolysis-driven and cochaperone-regulated conformational cycle are poorly understood. We used fluorescence spectroscopy to analyze, in real time and at single-molecule resolution, the effects of nucleotides and cochaperones on the conformation of Ssc1, a mitochondrial member of the family. We report that the conformation of its ADP state is unexpectedly heterogeneous, in contrast to a uniform ATP state. Substrates are actively involved in determining the conformation of Ssc1. The J protein Mdj1 does not interact transiently with the chaperone, as generally believed, but rather is released slowly upon ATP hydrolysis. Analysis of the major bacterial Hsp70 revealed important differences between highly homologous members of the family, possibly explaining tuning of Hsp70 chaperones to meet specific functions in different organisms and cellular compartments. 2010 Elsevier Inc. All rights reserved.

  18. Tumor imaging and targeting potential of an Hsp70-derived 14-mer peptide.

    Directory of Open Access Journals (Sweden)

    Mathias Gehrmann

    Full Text Available We have previously used a unique mouse monoclonal antibody cmHsp70.1 to demonstrate the selective presence of a membrane-bound form of Hsp70 (memHsp70 on a variety of leukemia cells and on single cell suspensions derived from solid tumors of different entities, but not on non-transformed cells or cells from corresponding 'healthy' tissue. This antibody can be used to image tumors in vivo and target them for antibody-dependent cellular cytotoxicity. Tumor-specific expression of memHsp70 therefore has the potential to be exploited for theranostic purposes. Given the advantages of peptides as imaging and targeting agents, this study assessed whether a 14-mer tumor penetrating peptide (TPP; TKDNNLLGRFELSG, the sequence of which is derived from the oligomerization domain of Hsp70 which is expressed on the cell surface of tumor cells, can also be used for targeting membrane Hsp70 positive (memHsp70+ tumor cells, in vitro.The specificity of carboxy-fluorescein (CF- labeled TPP (TPP to Hsp70 was proven in an Hsp70 knockout mammary tumor cell system. TPP specifically binds to different memHsp70+ mouse and human tumor cell lines and is rapidly taken up via endosomes. Two to four-fold higher levels of CF-labeled TPP were detected in MCF7 (82% memHsp70+ and MDA-MB-231 (75% memHsp70+ cells compared to T47D cells (29% memHsp70+ that exhibit a lower Hsp70 membrane positivity. After 90 min incubation, TPP co-localized with mitochondrial membranes in memHsp70+ tumors. Although there was no evidence that any given vesicle population was specifically localized, fluorophore-labeled cmHsp70.1 antibody and TPP preferentially accumulated in the proximity of the adherent surface of cultured cells. These findings suggest a potential association between membrane Hsp70 expression and cytoskeletal elements that are involved in adherence, the establishment of intercellular synapses and/or membrane reorganization.This study demonstrates the specific binding and rapid

  19. Role of membrane Hsp70 in radiation sensitivity of tumor cells

    International Nuclear Information System (INIS)

    Murakami, Naoya; Kühnel, Annett; Schmid, Thomas E.; Ilicic, Katarina; Stangl, Stefan; Braun, Isabella S.; Gehrmann, Mathias; Molls, Michael; Itami, Jun; Multhoff, Gabriele

    2015-01-01

    The major stress-inducible heat shock protein 70 (Hsp70) is frequently overexpressed in the cytosol and integrated in the plasma membrane of tumor cells via lipid anchorage. Following stress such as non-lethal irradiation Hsp70 synthesis is up-regulated. Intracellular located Hsp70 is known to exert cytoprotective properties, however, less is known about membrane (m)Hsp70. Herein, we investigate the role of mHsp70 in the sensitivity towards irradiation in tumor sublines that differ in their cytosolic and/or mHsp70 levels. The isogenic human colon carcinoma sublines CX + with stable high and CX − with stable low expression of mHsp70 were generated by fluorescence activated cell sorting, the mouse mammary carcinoma sublines 4 T1 (4 T1 ctrl) and Hsp70 knock-down (4 T1 Hsp70 KD) were produced using the CRISPR/Cas9 system, and the Hsp70 down-regulation in human lung carcinoma sublines H1339 ctrl/H1339 HSF-1 KD and EPLC-272H ctrl/EPLC-272H HSF-1 KD was achieved by small interfering (si)RNA against Heat shock factor 1 (HSF-1). Cytosolic and mHsp70 was quantified by Western blot analysis/ELISA and flow cytometry; double strand breaks (DSBs) and apoptosis were measured by flow cytometry using antibodies against γH2AX and real-time PCR (RT-PCR) using primers and antibodies directed against apoptosis related genes; and radiation sensitivity was determined using clonogenic cell surviving assays. CX + /CX − tumor cells exhibited similar cytosolic but differed significantly in their mHsp70 levels, 4 T1 ctrl/4 T1 Hsp70 KD cells showed significant differences in their cytosolic and mHsp70 levels and H1339 ctrl/H1339 HSF-1 KD and EPLC-272H ctrl/EPLC-272H HSF-1 KD lung carcinoma cell sublines had similar mHsp70 but significantly different cytosolic Hsp70 levels. γH2AX was significantly up-regulated in irradiated CX − and 4 T1 Hsp70 KD with low basal mHsp70 levels, but not in their mHsp70 high expressing counterparts, irrespectively of their cytosolic Hsp70 content. After

  20. Investigating the Chaperone Properties of a Novel Heat Shock Protein, Hsp70.c, from Trypanosoma brucei

    Directory of Open Access Journals (Sweden)

    Adélle Burger

    2014-01-01

    Full Text Available The neglected tropical disease, African Trypanosomiasis, is fatal and has a crippling impact on economic development. Heat shock protein 70 (Hsp70 is an important molecular chaperone that is expressed in response to stress and Hsp40 acts as its co-chaperone. These proteins play a wide range of roles in the cell and they are required to assist the parasite as it moves from a cold blooded insect vector to a warm blooded mammalian host. A novel cytosolic Hsp70, from Trypanosoma brucei, TbHsp70.c, contains an acidic substrate binding domain and lacks the C-terminal EEVD motif. The ability of a cytosolic Hsp40 from Trypanosoma brucei J protein 2, Tbj2, to function as a co-chaperone of TbHsp70.c was investigated. The main objective was to functionally characterize TbHsp70.c to further expand our knowledge of parasite biology. TbHsp70.c and Tbj2 were heterologously expressed and purified and both proteins displayed the ability to suppress aggregation of thermolabile MDH and chemically denatured rhodanese. ATPase assays revealed a 2.8-fold stimulation of the ATPase activity of TbHsp70.c by Tbj2. TbHsp70.c and Tbj2 both demonstrated chaperone activity and Tbj2 functions as a co-chaperone of TbHsp70.c. In vivo heat stress experiments indicated upregulation of the expression levels of TbHsp70.c.

  1. PREFERENTIAL SECRETION OF INDUCIBLE HSP70 BY VITILIGO MELANOCYTES UNDER STRESS

    Science.gov (United States)

    Mosenson, Jeffrey A.; Flood, Kelsey; Klarquist, Jared; Eby, Jonathan M.; Koshoffer, Amy; Boissy, Raymond E.; Overbeck, Andreas; C.Tung, Rebecca; Poole, I. Caroline Le

    2014-01-01

    SUMMARY Inducible HSP70 (HSP70i) chaperones peptides from stressed cells, protecting them from apoptosis. Upon extracellular release, HSP70i serves an adjuvant function, enhancing immune responses to bound peptides. We questioned whether HSP70i differentially protects control and vitiligo melanocytes from stress and subsequent immune responses. We compared expression of HSP70i in skin samples, evaluated the viability of primary vitiligo and control melanocytes exposed to bleaching phenols, and measured secreted HSP70i. We determined whether HSP70i traffics to melanosomes to contact immunogenic proteins by cell fractionation, western blotting, electron microscopy and confocal microscopy. Viability of vitiligo and control melanocytes was equally affected under stress. However, vitiligo melanocytes secreted increased amounts of HSP70i in response to MBEH, corroborating with aberrant HSP70i expression in patient skin. Intracellular HSP70i colocalized with melanosomes, and more so in response to MBEH in vitiligo melanocytes. Thus whereas either agent is cytotoxic to melanocytes, MBEH preferentially induces immune responses to melanocytes. PMID:24354861

  2. Epigallocatechin-3-gallate suppresses the expression of HSP70 and HSP90 and exhibits anti-tumor activity in vitro and in vivo

    International Nuclear Information System (INIS)

    Tran, Phan LCHB; Kim, Soo-A; Choi, Hong Seok; Yoon, Jung-Hoon; Ahn, Sang-Gun

    2010-01-01

    Epigallocatechin-3-gallate (EGCG), one of the major catechins in green tea, is a potential chemopreventive agent for various cancers. The aim of this study was to examine the effect of EGCG on the expression of heat shock proteins (HSPs) and tumor suppression. Cell colony formation was evaluated by a soft agar assay. Transcriptional activity of HSP70 and HSP90 was determined by luciferase reporter assay. An EGCG-HSPs complex was prepared using EGCG attached to the cyanogen bromide (CNBr)-activated Sepharose 4B. In vivo effect of EGCG on tumor growth was examined in a xenograft model. Treatment with EGCG decreased cell proliferation and colony formation of MCF-7 human breast cancer cells. EGCG specifically inhibited the expression of HSP70 and HSP90 by inhibiting the promoter activity of HSP70 and HSP90. Pretreatment with EGCG increased the stress sensitivity of MCF-7 cells upon heat shock (44°C for 1 h) or oxidative stress (H 2 O 2 , 500 μM for 24 h). Moreover, treatment with EGCG (10 mg/kg) in a xenograft model resulted in delayed tumor incidence and reduced tumor size, as well as the inhibition of HSP70 and HSP90 expression. Overall, these findings demonstrate that HSP70 and HSP90 are potent molecular targets of EGCG and suggest EGCG as a drug candidate for the treatment of human cancer

  3. Pharmacophore modeling, virtual screening and molecular docking of ATPase inhibitors of HSP70.

    Science.gov (United States)

    Sangeetha, K; Sasikala, R P; Meena, K S

    2017-10-01

    Heat shock protein 70 is an effective anticancer target as it influences many signaling pathways. Hence the study investigated the important pharmacophore feature required for ATPase inhibitors of HSP70 by generating a ligand based pharmacophore model followed by virtual based screening and subsequent validation by molecular docking in Discovery studio V4.0. The most extrapolative pharmacophore model (hypotheses 8) consisted of four hydrogen bond acceptors. Further validation by external test set prediction identified 200 hits from Mini Maybridge, Drug Diverse, SCPDB compounds and Phytochemicals. Consequently, the screened compounds were refined by rule of five, ADMET and molecular docking to retain the best competitive hits. Finally Phytochemical compounds Muricatetrocin B, Diacetylphiladelphicalactone C, Eleutheroside B and 5-(3-{[1-(benzylsulfonyl)piperidin-4-yl]amino}phenyl)- 4-bromo-3-(carboxymethoxy)thiophene-2-carboxylic acid were obtained as leads to inhibit the ATPase activity of HSP70 in our findings and thus can be proposed for further in vitro and in vivo evaluation. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. The p53/HSP70 inhibitor, 2-phenylethynesulfonamide, causes oxidative stress, unfolded protein response and apoptosis in rainbow trout cells

    Energy Technology Data Exchange (ETDEWEB)

    Zeng, Fanxing; Tee, Catherine; Liu, Michelle [Department of Biology, University of Waterloo, Waterloo, Ontario N2L 3G1 (Canada); Sherry, James P. [Aquatic Contaminants Research Division, Environment Canada, Burlington, Ontario L7R 4A6 (Canada); Dixon, Brian; Duncker, Bernard P. [Department of Biology, University of Waterloo, Waterloo, Ontario N2L 3G1 (Canada); Bols, Niels C., E-mail: ncbols@uwaterloo.ca [Department of Biology, University of Waterloo, Waterloo, Ontario N2L 3G1 (Canada)

    2014-01-15

    Highlights: •2-Phenylethynesulfonamide (PES) is an inhibitor of p53 and HSP 70 in mammals. •In the fish epithelial cell line, RTgill-W1, PES enhanced ROS generation and was cytotoxic. •RTgill-W1 death was by apoptosis and blocked by the anti-oxidant N-acetylcysteine. •This is the first report linking PES-induced cell death to ROS. •With this background PES should be useful for studying fish cell survival pathways. -- Abstract: The effect of 2-phenylethynesulfonamide (PES), which is a p53 and HSP70 inhibitor in mammalian cells, was studied on the rainbow trout (Oncorhynchus mykiss) gill epithelial cell line, RTgill-W1, in order to evaluate PES as a tool for understanding the cellular survival pathways operating in fish. As judged by three viability assays, fish cells were killed by 24 h exposures to PES, but cell death was blocked by the anti-oxidant N-acetylcysteine (NAC). Cell death had several hallmarks of apoptosis: DNA laddering, nuclear fragmentation, Annexin V staining, mitochondrial membrane potential decline, and caspases activation. Reactive oxygen species (ROS) production peaked in several hours after the addition of PES and before cell death. HSP70 and BiP levels were higher in cultures treated with PES for 24 h, but this was blocked by NAC. As well, PES treatment caused HSP70, BiP and p53 to accumulate in the detergent-insoluble fraction, and this too was prevented by NAC. Of several possible scenarios to explain the results, the following one is the simplest. PES enhances the generation of ROS, possibly by inhibiting the anti-oxidant actions of p53 and HSP70. ER stress arises from the ROS and from PES inhibiting the chaperone activities of HSP70. The ER stress in turn initiates the unfolded protein response (UPR), but this fails to restore ER homeostasis so proteins aggregate and cells die. Despite these multiple actions, PES should be useful for studying fish cellular survival pathways.

  5. Identification and in silico analysis of the Citrus HSP70 molecular chaperone gene family

    Directory of Open Access Journals (Sweden)

    Luciano G. Fietto

    2007-01-01

    Full Text Available The completion of the genome sequencing of the Arabidopsis thaliana model system provided a powerful molecular tool for comparative analysis of gene families present in the genome of economically relevant plant species. In this investigation, we used the sequences of the Arabidopsis Hsp70 gene family to identify and annotate the Citrus Hsp70 genes represented in the CitEST database. Based on sequence comparison analysis, we identified 18 clusters that were further divided into 5 subgroups encoding four mitochondrial mtHsp70s, three plastid csHsp70s, one ER luminal Hsp70 BiP, two HSP110/SSE-related proteins and eight cytosolic Hsp/Hsc70s. We also analyzed the expression profile by digital Northern of each Hsp70 transcript in different organs and in response to stress conditions. The EST database revealed a distinct population distribution of Hsp70 ESTs among isoforms and across the organs surveyed. The Hsp70-5 isoform was highly expressed in seeds, whereas BiP, mitochondrial and plastid HSp70 mRNAs displayed a similar expression profile in the organs analyzed, and were predominantly represented in flowers. Distinct Hsp70 mRNAs were also differentially expressed during Xylella infection and Citrus tristeza viral infection as well as during water deficit. This in silico study sets the groundwork for future investigations to fully characterize functionally the Citrus Hsp70 family and underscores the relevance of Hsp70s in response to abiotic and biotic stresses in Citrus.

  6. The role of HSP70 in mediating age-dependent mortality in sepsis

    Science.gov (United States)

    McConnell, Kevin W.; Fox, Amy C.; Clark, Andrew T.; Chang, Nai-Yuan Nicholas; Dominguez, Jessica A.; Farris, Alton B.; Buchman, Timothy G.; Hunt, Clayton R.; Coopersmith, Craig M.

    2011-01-01

    Sepsis is primarily a disease of the aged, with increased incidence and mortality occurring in aged hosts. Heat shock protein (HSP) 70 plays an important role in both healthy aging and the stress response to injury. The purpose of this study was to determine the role of HSP70 in mediating mortality and the host inflammatory response in aged septic hosts. Sepsis was induced in both young (6–12week old) and aged (16–17 month old) HSP70−/− and wild type (WT) mice to determine if HSP70 modulated outcome in an age-dependent fashion. Young HSP70−/− and WT mice subjected to cecal ligation and puncture (CLP), Pseudomonas aeruginosa pneumonia or Streptococcus pneumoniae pneumonia had no differences in mortality, suggesting HSP70 does not mediate survival in young septic hosts. In contrast, mortality was higher in aged HSP70−/− mice than aged WT mice subjected to CLP (p=0.01), suggesting HSP70 mediates mortality in sepsis in an age-dependent fashion. Compared to WT mice, aged septic HSP70−/− mice had increased gut epithelial apoptosis and pulmonary inflammation. In addition, HSP70−/−mice had increased systemic levels of TNF-α, IL-6, IL-10 and IL-1β compared to WT mice. These data demonstrate that HSP70 is a key determinant of mortality in aged but not young hosts in sepsis. HSP70 may play a protective role in an age-dependent response to sepsis by preventing excessive gut apoptosis and both pulmonary and systemic inflammation. PMID:21296977

  7. Proteomics shows Hsp70 does not bind peptide sequences indiscriminately in vivo

    International Nuclear Information System (INIS)

    Grossmann, Michael E.; Madden, Benjamin J.; Gao, Fan; Pang, Yuan-Ping; Carpenter, John E.; McCormick, Daniel; Young, Charles Y.F.

    2004-01-01

    Heat shock protein 70 (Hsp70) binds peptide and has several functions that include protein folding, protein trafficking, and involvement with immune function. However, endogenous Hsp70-binding peptides had not previously been identified. Therefore, we eluted and identified several hundred endogenously bound peptides from Hsp70 using liquid chromatography ion trap mass spectrophotometry (LC-ITMS). Our work shows that the peptides are capable of binding Hsp70 as previously described. They are generally 8-26 amino acids in length and correspond to specific regions of many proteins. Through computationally assisted analysis of peptides eluted from Hsp70 we determined variable amino acid sequences, including a 5 amino acid core sequence that Hsp70 favorably binds. We also developed a computer algorithm that predicts Hsp70 binding within proteins. This work helps to define what peptides are bound by Hsp70 in vivo and suggests that Hsp70 facilitates peptide selection by aiding a funneling mechanism that is flexible but allows only a limited number of peptides to be processed

  8. HIF-1α-induced HSP70 regulates anabolic responses in articular chondrocytes under hypoxic conditions.

    Science.gov (United States)

    Tsuchida, Shinji; Arai, Yuji; Takahashi, Kenji A; Kishida, Tsunao; Terauchi, Ryu; Honjo, Kuniaki; Nakagawa, Shuji; Inoue, Hiroaki; Ikoma, Kazuya; Ueshima, Keiichiro; Matsuki, Tomohiro; Mazda, Osam; Kubo, Toshikazu

    2014-08-01

    We assessed whether heat shock protein 70 (HSP70) is involved in hypoxia inducible factor 1 alpha (HIF-1α)-dependent anabolic pathways in articular chondrocytes under hypoxic conditions. Primary rabbit chondrocytes were cultured under normoxia (20% oxygen condition) or hypoxia (1% oxygen condition). Alternatively, cells cultured under normoxia were treated with CoCl2 , which induces HIF-1α, to simulate hypoxia, or transfected with siRNAs targeting HIF-1α (si-HIF-1α) and HSP70 (si-HSP70) under hypoxia. HSP70 expression was enhanced by the increased expression of HIF-1α under hypoxia or simulated hypoxia, but not in the presence of si-HIF-1α. Hypoxia-induced overexpression of ECM genes was significantly suppressed by si-HIF-1α or si-HSP70. Cell viability positively correlated with hypoxia, but transfection with si-HIF-1α or si-HSP70 abrogated the chondroprotective effects of hypoxia. Although LDH release from sodium nitroprusside-treated cells and the proportion of TUNEL positive cells were decreased under hypoxia, transfection with si-HIF-1α or si-HSP70 almost completely blocked these effects. These findings indicated that HIF-1α-induced HSP70 overexpression increased the expression levels of ECM genes and cell viability, and protected chondrocytes from apoptosis. HIF-1α may regulate the anabolic effects of chondrocytes under hypoxic conditions by regulating HSP70 expression. © 2014 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  9. Hsp70 facilitates trans-membrane transport of bacterial ADP-ribosylating toxins into the cytosol of mammalian cells.

    Science.gov (United States)

    Ernst, Katharina; Schmid, Johannes; Beck, Matthias; Hägele, Marlen; Hohwieler, Meike; Hauff, Patricia; Ückert, Anna Katharina; Anastasia, Anna; Fauler, Michael; Jank, Thomas; Aktories, Klaus; Popoff, Michel R; Schiene-Fischer, Cordelia; Kleger, Alexander; Müller, Martin; Frick, Manfred; Barth, Holger

    2017-06-02

    Binary enterotoxins Clostridium (C.) botulinum C2 toxin, C. perfringens iota toxin and C. difficile toxin CDT are composed of a transport (B) and a separate non-linked enzyme (A) component. Their B-components mediate endocytic uptake into mammalian cells and subsequently transport of the A-components from acidic endosomes into the cytosol, where the latter ADP-ribosylate G-actin resulting in cell rounding and cell death causing clinical symptoms. Protein folding enzymes, including Hsp90 and peptidyl-prolyl cis/trans isomerases facilitate transport of the A-components across endosomal membranes. Here, we identified Hsp70 as a novel host cell factor specifically interacting with A-components of C2, iota and CDT toxins to facilitate their transport into the cell cytosol. Pharmacological Hsp70-inhibition specifically prevented pH-dependent trans-membrane transport of A-components into the cytosol thereby protecting living cells and stem cell-derived human miniguts from intoxication. Thus, Hsp70-inhibition might lead to development of novel therapeutic strategies to treat diseases associated with bacterial ADP-ribosylating toxins.

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

    Directory of Open Access Journals (Sweden)

    Michael Roth

    2009-01-01

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

  11. Engagement of Components of DNA-Break Repair Complex and NFκB in Hsp70A1A Transcription Upregulation by Heat Shock.

    Science.gov (United States)

    Hazra, Joyita; Mukherjee, Pooja; Ali, Asif; Poddar, Soumita; Pal, Mahadeb

    2017-01-01

    An involvement of components of DNA-break repair (DBR) complex including DNA-dependent protein kinase (DNA-PK) and poly-ADP-ribose polymerase 1 (PARP-1) in transcription regulation in response to distinct cellular signalling has been revealed by different laboratories. Here, we explored the involvement of DNA-PK and PARP-1 in the heat shock induced transcription of Hsp70A1A. We find that inhibition of both the catalytic subunit of DNA-PK (DNA-PKc), and Ku70, a regulatory subunit of DNA-PK holo-enzyme compromises transcription of Hsp70A1A under heat shock treatment. In immunoprecipitation based experiments we find that Ku70 or DNA-PK holoenzyme associates with NFκB. This NFκB associated complex also carries PARP-1. Downregulation of both NFκB and PARP-1 compromises Hsp70A1A transcription induced by heat shock treatment. Alteration of three bases by site directed mutagenesis within the consensus κB sequence motif identified on the promoter affected inducibility of Hsp70A1A transcription by heat shock treatment. These results suggest that NFκB engaged with the κB motif on the promoter cooperates in Hsp70A1A activation under heat shock in human cells as part of a DBR complex including DNA-PK and PARP-1.

  12. Protein synthesis in TE 671/RD (human rabdomiosarcoma) cells treated with thapsigargin and hyperthermia: impairment of HSP 70 induction.

    Science.gov (United States)

    Delpino, A; Piselli, P; Mangano, G

    1995-01-01

    In this study we considered the quantitative and qualitative changes of protein synthetic activity occurring in TE 671/RD cells treated with thapsigargin (TG), with hyperthermia (HT) or with a combination of both these agents. In cells treated with TG (100 nM, continuous exposure), the overall protein synthetic activity was initially inhibited but subsequently recovered to about 60% of the initial level. Chronic TG exposure was also able to induce the expression of GRP 78. The rate of synthesis of GRP 78, after a lag period of about 2 h, increased gradually to reach a maximum (9-fold induction) after 6 h of TG-treatment and was then maintained at that level up to 18 h. A weak induction of GRP 94 was observed following 6-8 h of continuous exposure to TG. In cells treated with HT (43 degrees C for 30 min), a typical heat shock response was observed: in particular, the relative rate of synthesis of HSP 70 (the major heat-inducible mammalian heat shock protein) was increased 10-fold over the constitutive level. The heat-promoted induction of HSP 70 was significantly reduced by concomitant or previous exposure to TG. When TG and HT were administred simultaneously, the increase in HSP 70 synthesis was only 4.7-fold over the control level, while in cells pre-treated for 1 h with TG before the hyperthermic challenge the rate of HSP 70 synthesis was only stimulated 2-fold. In both these conditions, by contrast, it was apparent that HT did not affect the TG-promoted induction of GRP 78. The correlations between the TG-induced mobilization of cytosolic Ca2+ and the effects on protein synthesis are discussed.

  13. BAG3 Expression in Glioblastoma Cells Promotes Accumulation of Ubiquitinated Clients in an Hsp70-dependent Manner*

    Science.gov (United States)

    Gentilella, Antonio; Khalili, Kamel

    2011-01-01

    Disposal of damaged proteins and protein aggregates is a prerequisite for the maintenance of cellular homeostasis and impairment of this disposal can lead to a broad range of pathological conditions, most notably in brain-associated disorders including Parkinson and Alzheimer diseases, and cancer. In this respect, the Protein Quality Control (PQC) pathway plays a central role in the clearance of damaged proteins. The Hsc/Hsp70-co-chaperone BAG3 has been described as a new and critical component of the PQC in several cellular contexts. For example, the expression of BAG3 in the rodent brain correlates with the engagement of protein degradation machineries in response to proteotoxic stress. Nevertheless, little is known about the molecular events assisted by BAG3. Here we show that ectopic expression of BAG3 in glioblastoma cells leads to the activation of an HSF1-driven stress response, as attested by transcriptional activation of BAG3 and Hsp70. BAG3 overexpression determines an accumulation of ubiquitinated proteins and this event requires the N-terminal region, WW domain of BAG3 and the association of BAG3 with Hsp70. The ubiquitination mainly occurs on BAG3-client proteins and the inhibition of proteasomal activity results in a further accumulation of ubiquitinated clients. At the cellular level, overexpression of BAG3 in glioblastoma cell lines, but not in non-glial cells, results in a remarkable decrease in colony formation capacity and this effect is reverted when the binding of BAG3 to Hsp70 is impaired. These observations provide the first evidence for an involvement of BAG3 in the ubiquitination and turnover of its partners. PMID:21233200

  14. Conserved structure and expression of hsp70 paralogs in teleost fishes

    DEFF Research Database (Denmark)

    Metzger, David C.H.; Hansen, Jakob Hemmer; Schulte, Patricia M.

    2016-01-01

    present in the F. heteroclitus genome. Comparison of expression patterns in F. heteroclitus and Gasterosteus aculeatus demonstrates that hsp70-2 has a higher fold increase than hsp70-1 following heat shock in gill but not in muscle tissue, revealing a conserved difference in expression patterns between...

  15. Association of HSP70 and its co-chaperones with Alzheimer's disease

    NARCIS (Netherlands)

    L. Broer (Linda); M.A. Ikram (Arfan); M. Schuur (Maaike); A.L. DeStefano (Anita); J.C. Bis (Joshua); F. Liu (Fan); F. Rivadeneira Ramirez (Fernando); A.G. Uitterlinden (André); A. Beiser (Alexa); W.T. Longstreth Jr; A. Hofman (Albert); Y.S. Aulchenko (Yurii); S. Seshadri (Sudha); A.L. Fitzpatrick (Annette); B.A. Oostra (Ben); M.M.B. Breteler (Monique); P. Tikka-Kleemola (Päivi)

    2011-01-01

    textabstractThe heat shock protein (HSP) 70 family has been implicated in the pathology of Alzheimer's disease (AD). In this study, we examined common genetic variations in the 80 genes encoding HSP70 and its co-chaperones. We conducted a study in a series of 462 patients and 5238 unaffected

  16. Functional analysis of the Hikeshi-like protein and its interaction with HSP70 in Arabidopsis

    Energy Technology Data Exchange (ETDEWEB)

    Koizumi, Shinya; Ohama, Naohiko; Mizoi, Junya [Laboratory of Plant Molecular Physiology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657 (Japan); Shinozaki, Kazuo [RIKEN Plant Science Center, 1-7-22 Suehiro-cho, Tsurumi, Yokohama, Kanagawa 230-0045 (Japan); Yamaguchi-Shinozaki, Kazuko, E-mail: akys@mail.ecc.u-tokyo.ac.jp [Laboratory of Plant Molecular Physiology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657 (Japan)

    2014-07-18

    Highlights: • HKL, a Hikeshi homologous gene is identified in Arabidopsis. • HKL interacts with two HSP70 isoforms and regulates the subcellular localization of HSC70-1. • The two HSP70 translocate into nucleus in response to heat stress. • Overexpression of HKL confers thermotolerance in transgenic plants. - Abstract: Heat shock proteins (HSPs) refold damaged proteins and are an essential component of the heat shock response. Previously, the 70 kDa heat shock protein (HSP70) has been reported to translocate into the nucleus in a heat-dependent manner in many organisms. In humans, the heat-induced translocation of HSP70 requires the nuclear carrier protein Hikeshi. In the Arabidopsis genome, only one gene encodes a protein with high homology to Hikeshi, and we named this homolog Hikeshi-like (HKL) protein. In this study, we show that two Arabidopsis HSP70 isoforms accumulate in the nucleus in response to heat shock and that HKL interacts with these HSP70s. Our histochemical analysis revealed that HKL is predominantly expressed in meristematic tissues, suggesting the potential importance of HKL during cell division in Arabidopsis. In addition, we show that HKL regulates HSP70 localization, and HKL overexpression conferred thermotolerance to transgenic Arabidopsis plants. Our results suggest that HKL plays a positive role in the thermotolerance of Arabidopsis plants and cooperatively interacts with HSP70.

  17. High mobility group protein DSP1 negatively regulates HSP70 transcription in Crassostrea hongkongensis

    Energy Technology Data Exchange (ETDEWEB)

    Miao, Zongyu; Xu, Delin; Cui, Miao; Zhang, Qizhong, E-mail: zhangqzdr@126.com

    2016-06-10

    HSP70 acts mostly as a molecular chaperone and plays important roles in facilitating the folding of nascent peptides as well as the refolding or degradation of the denatured proteins. Under stressed conditions, the expression level of HSP70 is upregulated significantly and rapidly, as is known to be achieved by various regulatory factors controlling the transcriptional level. In this study, a high mobility group protein DSP1 was identified by DNA-affinity purification from the nuclear extracts of Crassostrea hongkongensis using the ChHSP70 promoter as a bait. The specific interaction between the prokaryotically expressed ChDSP1 and the FITC-labeled ChHSP70 promoter was confirmed by EMSA analysis. ChDSP1 was shown to negatively regulate ChHSP70 promoter expression by Luciferase Reporter Assay in the heterologous HEK293T cells. Both ChHSP70 and ChDSP1 transcriptions were induced by either thermal or CdCl{sub 2} stress, while the accumulated expression peaks of ChDSP1 were always slightly delayed when compared with that of ChHSP70. This indicates that ChDSP1 is involved, very likely to exert its suppressive role, in the recovery of the ChHSP70 expression from the induced level to its original state. This study is the first to report negative regulator of HSP70 gene transcription, and provides novel insights into the mechanisms controlling heat shock protein expression. -- Highlights: •HMG protein ChDSP1 shows affinity to ChHSP70 promoter in Crassostrea hongkongensis. •ChDSP1 negatively regulates ChHSP70 transcription. •ChHSP70 and ChDSP1 transcriptions were coordinately induced by thermal/Cd stress. •ChDSP1 may contribute to the recovery of the induced ChHSP70 to its original state. •This is the first report regarding negative regulator of HSP70 transcription.

  18. Molecular analysis of Hsp70 mechanisms in plants and their function in response to stress.

    Science.gov (United States)

    Usman, Magaji G; Rafii, Mohd Y; Martini, Mohammad Y; Yusuff, Oladosu A; Ismail, Mohd R; Miah, Gous

    2017-04-01

    Studying the strategies of improving abiotic stress tolerance is quite imperative and research under this field will increase our understanding of response mechanisms to abiotic stress such as heat. The Hsp70 is an essential regulator of protein having the tendency to maintain internal cell stability like proper folding protein and breakdown of unfolded proteins. Hsp70 holds together protein substrates to help in movement, regulation, and prevent aggregation under physical and or chemical pressure. However, this review reports the molecular mechanism of heat shock protein 70 kDa (Hsp70) action and its structural and functional analysis, research progress on the interaction of Hsp70 with other proteins and their interaction mechanisms as well as the involvement of Hsp70 in abiotic stress responses as an adaptive defense mechanism.

  19. Expression analysis of HSP70 in the testis of Octopus tankahkeei under thermal stress.

    Science.gov (United States)

    Long, Ling-Li; Han, Ying-Li; Sheng, Zhang; Du, Chen; Wang, You-Fa; Zhu, Jun-Quan

    2015-09-01

    The gene encoding heat shock protein 70 (HSP70) was identified in Octopus tankahkeei by homologous cloning and rapid amplification of cDNA ends (RACE). The full-length cDNA (2471 bp) consists of a 5'-untranslated region (UTR) (89 bp), a 3'-UTR (426 bp), and an open reading frame (1956 bp) that encodes 651 amino acid residues with a predicted molecular mass of 71.8 kDa and an isoelectric point of 5.34. Based on the amino acid sequence analysis and multiple sequence alignment, this cDNA is a member of cytoplasmic hsp70 subfamily of the hsp70 family and was designated as ot-hsp70. Tissue expression analysis showed that HSP70 expression is highest in the testes when all examined organs were compared. Immunohistochemistry analysis, together with hematoxylin-eosin staining, revealed that the HSP70 protein was expressed in all spermatogenic cells, but not in fibroblasts. In addition, O. tankahkeei were heat challenged by exposure to 32 °C seawater for 2 h, then returned to 13 °C for various recovery time (0-24 h). Relative expression of ot-hsp70 mRNA in the testes was measured at different time points post-challenge by quantitative real-time PCR. A clear time-dependent mRNA expression of ot-hsp70 after thermal stress indicates that the HSP70 gene is inducible. Ultrastructural changes of the heat-stressed testis were observed by transmission electron microscopy. We suggest that HSP70 plays an important role in spermatogenesis and testis protection against thermal stress in O. tankahkeei. Copyright © 2015 Elsevier Inc. All rights reserved.

  20. Cathepsin B is involved in the heat shock induced cardiomyocytes apoptosis as well as the anti-apoptosis effect of HSP-70.

    Science.gov (United States)

    Hsu, Shu-Fen; Hsu, Chuan-Chih; Cheng, Bor-Chih; Lin, Cheng-Hsien

    2014-11-01

    Cathepsin B is one of the major lysosomal cysteine proteases that plays an important role in apoptosis. Herein, we investigated whether Cathepsin B is involved in cardiomyocyte apoptosis caused by hyperthermic injury (HI) and heat shock protein (HSP)-70 protects these cells from HI-induced apoptosis mediated by Cathepsin. HI was produced in H9C2 cells by putting them in a circulating 43 °C water bath for 120 min, whereas preinduction of HSP-70 was produced in H9C2 cells by mild heat preconditioning (or putting them in 42 °C water bath for 30 min) 8 h before the start of HI. It was found that HI caused both cardiomyocyte apoptosis and increased Cathepsin B activity in H9C2 cells. E-64-c, in addition to reducing Cathepsin B activity, significantly attenuated HI-induced cardiomyocyte apoptosis (evidenced by increased apoptotic cell numbers, increased tuncated Bid (t-Bid), increased cytochrome C, increased caspase-9/-3, and decreased Bcl-2/Bax) in H9C2 cells. In addition, preinduction of HSP-70 by mild heat preconditioning or inhibition of HSP-70 by Tripolide significantly attenuated or exacerbated respectively both the cardiomyocyte apoptosis and increased Cathepsin B activity in H9C2 cells. Furthermore, the beneficial effects of pre-induction of HSP-70 by mild heat production in reducing both cardiomyocyte apoptosis and increased Cathepsin B activity caused by HI can be significantly reduced by Triptolide preconditioning. These results indicate that Cathepsin B is involved in HI-induced cardiomyocyte apoptosis in H9C2 cells and HSP-70 protects these cells from HI-induced cardiomyocyte apoptosis through Cathepsin B pathways.

  1. Stress-induced localization of HSPA6 (HSP70B') and HSPA1A (HSP70-1) proteins to centrioles in human neuronal cells.

    Science.gov (United States)

    Khalouei, Sam; Chow, Ari M; Brown, Ian R

    2014-05-01

    The localization of yellow fluorescent protein (YFP)-tagged HSP70 proteins was employed to identify stress-sensitive sites in human neurons following temperature elevation. Stable lines of human SH-SY5Y neuronal cells were established that expressed YFP-tagged protein products of the human inducible HSP70 genes HSPA6 (HSP70B') and HSPA1A (HSP70-1). Following a brief period of thermal stress, YFP-tagged HSPA6 and HSPA1A rapidly appeared at centrioles in the cytoplasm of human neuronal cells, with HSPA6 demonstrating a more prolonged signal compared to HSPA1A. Each centriole is composed of a distal end and a proximal end, the latter linking the centriole doublet. The YFP-tagged HSP70 proteins targeted the proximal end of centrioles (identified by γ-tubulin marker) rather than the distal end (centrin marker). Centrioles play key roles in cellular polarity and migration during neuronal differentiation. The proximal end of the centriole, which is involved in centriole stabilization, may be stress-sensitive in post-mitotic, differentiating human neurons.

  2. Hsp70 in the atrial neuroendocrine units of the snail, Achatina fulica.

    Science.gov (United States)

    Martynova, M G; Bystrova, O A; Shabelnikov, S V; Margulis, B A; Prokofjeva, D S

    2007-04-01

    Heat shock proteins (Hsps) are evolutionary conserved peptides well known as molecular chaperones and stress proteins. Elevated levels of extracellular Hsps in blood plasma have been observed during the stress responses and some diseases. Information on the cellular sources of extracellular Hsps and mechanisms regulating their release is still scanty. Here we showed the presence and localization of Hsp70 in the neuroendocrine system in the atrium of the snail, Achatina fulica. The occurrence of the peptide in snail atrium lysate was detected by Western blot analysis. Immunoperoxidase and immunogold staining demonstrated that Hsp70-immunoreactivity is mainly confined to the peculiar atrial neuroendocrine units which are formed by nerve fibers tightly contacted with large granular cells. Immunolabelling intensity differed in morphologically distinct types of secretory granules in the granular cells. The pictures of exocytosis of Hsp70-immunolabeled granules from the granular cells were observed. In nerve bundles, axon profiles with Hsp70-immunoreactive and those with non-immunoreactive neurosecretory granules were found. In addition, Hsp70-like material was also revealed in the granules of glia-interstitial cells that accompanied nerve fibers. Our findings provide an immuno-morphological basis for a role of Hsp70 in the functioning of the neuroendocrine system in the snail heart, and show that the atrial granular cells are a probable source of extracellular Hsp70 in the snail hemolymph.

  3. Hsp70-Bag3 interactions regulate cancer-related signaling networks.

    Science.gov (United States)

    Colvin, Teresa A; Gabai, Vladimir L; Gong, Jianlin; Calderwood, Stuart K; Li, Hu; Gummuluru, Suryaram; Matchuk, Olga N; Smirnova, Svetlana G; Orlova, Nina V; Zamulaeva, Irina A; Garcia-Marcos, Mikel; Li, Xiaokai; Young, Z T; Rauch, Jennifer N; Gestwicki, Jason E; Takayama, Shinichi; Sherman, Michael Y

    2014-09-01

    Bag3, a nucleotide exchange factor of the heat shock protein Hsp70, has been implicated in cell signaling. Here, we report that Bag3 interacts with the SH3 domain of Src, thereby mediating the effects of Hsp70 on Src signaling. Using several complementary approaches, we established that the Hsp70-Bag3 module is a broad-acting regulator of cancer cell signaling by modulating the activity of the transcription factors NF-κB, FoxM1, Hif1α, the translation regulator HuR, and the cell-cycle regulators p21 and survivin. We also identified a small-molecule inhibitor, YM-1, that disrupts the Hsp70-Bag3 interaction. YM-1 mirrored the effects of Hsp70 depletion on these signaling pathways, and in vivo administration of this drug was sufficient to suppress tumor growth in mice. Overall, our results defined Bag3 as a critical factor in Hsp70-modulated signaling and offered a preclinical proof-of-concept that the Hsp70-Bag3 complex may offer an appealing anticancer target. ©2014 American Association for Cancer Research.

  4. Broadening the functionality of a J-protein/Hsp70 molecular chaperone system.

    Science.gov (United States)

    Schilke, Brenda A; Ciesielski, Szymon J; Ziegelhoffer, Thomas; Kamiya, Erina; Tonelli, Marco; Lee, Woonghee; Cornilescu, Gabriel; Hines, Justin K; Markley, John L; Craig, Elizabeth A

    2017-10-01

    By binding to a multitude of polypeptide substrates, Hsp70-based molecular chaperone systems perform a range of cellular functions. All J-protein co-chaperones play the essential role, via action of their J-domains, of stimulating the ATPase activity of Hsp70, thereby stabilizing its interaction with substrate. In addition, J-proteins drive the functional diversity of Hsp70 chaperone systems through action of regions outside their J-domains. Targeting to specific locations within a cellular compartment and binding of specific substrates for delivery to Hsp70 have been identified as modes of J-protein specialization. To better understand J-protein specialization, we concentrated on Saccharomyces cerevisiae SIS1, which encodes an essential J-protein of the cytosol/nucleus. We selected suppressors that allowed cells lacking SIS1 to form colonies. Substitutions changing single residues in Ydj1, a J-protein, which, like Sis1, partners with Hsp70 Ssa1, were isolated. These gain-of-function substitutions were located at the end of the J-domain, suggesting that suppression was connected to interaction with its partner Hsp70, rather than substrate binding or subcellular localization. Reasoning that, if YDJ1 suppressors affect Ssa1 function, substitutions in Hsp70 itself might also be able to overcome the cellular requirement for Sis1, we carried out a selection for SSA1 suppressor mutations. Suppressing substitutions were isolated that altered sites in Ssa1 affecting the cycle of substrate interaction. Together, our results point to a third, additional means by which J-proteins can drive Hsp70's ability to function in a wide range of cellular processes-modulating the Hsp70-substrate interaction cycle.

  5. Cytotoxicity and Hsp 70 induction in Hep G2 cells in response to zearalenone and cytoprotection by sub-lethal heat shock

    International Nuclear Information System (INIS)

    Hassen, Wafa; Golli, Emna El; Baudrimont, Isabelle; Mobio, A. Theophile; Ladjimi, M. Moncef; Creppy, E. Edmond; Bacha, Hassen

    2005-01-01

    Zearalenone (ZEN) is a mycotoxin with several adverse effects in laboratory and domestic animals. The mechanism of ZEN toxicity that involves mainly binding to oestrogen receptors and inhibition of macromolecules synthesis is not fully understood. Using human hepatocytes Hep G2 cells as a model, the aim of this work was (i) to investigate the ability of ZEN to induce heat shock proteins Hsp 70 and (ii) to find out the mechanisms of ZEN cytotoxicity by examining cell proliferation and protein synthesis. Our study demonstrated that ZEN induces Hsp 70 expression in a time and dose-dependant manner; this induction occurs at non-cytotoxic concentrations, it could be therefore considered as a biomarker of toxicity. A cytoprotective effect of Hsp 70 was elicited when Hep G2 cells were exposed to Sub-Lethal heat shock prior to ZEN treatment and evidenced by a reduced ZEN cytolethality. This cytoprotection suggests that Hsp 70 may constitute an important cellular defence mechanism. Finally, our data show that ZEN is cytotoxic in Hep G2 cells by inhibiting cell proliferation and total protein synthesis and pointed out oxidative damage as possible pathway involved in ZEN toxicity; however, other investigations are needed to further confirm Zen induced oxidative stress

  6. Plasmodial Hsp70s are functionally adapted to the malaria parasite life cycle

    Directory of Open Access Journals (Sweden)

    Jude M Przyborski

    2015-06-01

    Full Text Available The human malaria parasite, Plasmodium falciparum, encodes a minimal complement of six heat shock protein 70s (PfHSP70s, some of which are highly expressed and are thought to play an important role in the survival and pathology of the parasite. In addition to canonical features of molecular chaperones, these HSP70s possess properties that reflect functional adaptation to a parasitic life style, including resistance to thermal insult during fever periods and host-parasite interactions. The parasite even exports an HSP70 to the host cell where it is likely to be involved in host cell modification. This review focuses on the features of the PfHSP70s, particularly with respect to their adaptation to the malaria parasite life cycle.

  7. Progranulin Recruits HSP70 to ?-Glucocerebrosidase and Is Therapeutic Against Gaucher Disease

    OpenAIRE

    Jian, Jinlong; Tian, Qing-Yun; Hettinghouse, Aubryanna; Zhao, Shuai; Liu, Helen; Wei, Jianlu; Grunig, Gabriele; Zhang, Wujuan; Setchell, Kenneth D.R.; Sun, Ying; Overkleeft, Herman S.; Chan, Gerald L.; Liu, Chuan-ju

    2016-01-01

    Highlights ? PGRN is required for lysosomal appearance of GCase and PGRN deficiency causes GCase/LIMP2 aggregation upon stress ? PGRN directly binds to GCase through a two-site mechanism ? PGRN recruits HSP70 to GCase and prevents GCase aggregation in response to stress ? PGRN derivative Pcgin binds to GCase and HSP70 and is therapeutic against Gaucher disease In this study, we demonstrate that PGRN directly binds to GCase and is required for the lysosomal appearance of GCase. In addition, HS...

  8. The exported chaperone Hsp70-x supports virulence functions for Plasmodium falciparum blood stage parasites.

    Directory of Open Access Journals (Sweden)

    Sarah C Charnaud

    Full Text Available Malaria is caused by five different Plasmodium spp. in humans each of which modifies the host erythrocyte to survive and replicate. The two main causes of malaria, P. falciparum and P. vivax, differ in their ability to cause severe disease, mainly due to differences in the cytoadhesion of infected erythrocytes (IE in the microvasculature. Cytoadhesion of P. falciparum in the brain leads to a large number of deaths each year and is a consequence of exported parasite proteins, some of which modify the erythrocyte cytoskeleton while others such as PfEMP1 project onto the erythrocyte surface where they bind to endothelial cells. Here we investigate the effects of knocking out an exported Hsp70-type chaperone termed Hsp70-x that is present in P. falciparum but not P. vivax. Although the growth of Δhsp70-x parasites was unaffected, the export of PfEMP1 cytoadherence proteins was delayed and Δhsp70-x IE had reduced adhesion. The Δhsp70-x IE were also more rigid than wild-type controls indicating changes in the way the parasites modified their host erythrocyte. To investigate the cause of this, transcriptional and translational changes in exported and chaperone proteins were monitored and some changes were observed. We propose that PfHsp70-x is not essential for survival in vitro, but may be required for the efficient export and functioning of some P. falciparum exported proteins.

  9. The exported chaperone Hsp70-x supports virulence functions for Plasmodium falciparum blood stage parasites

    Science.gov (United States)

    Charnaud, Sarah C.; Dixon, Matthew W. A.; Nie, Catherine Q.; Chappell, Lia; Sanders, Paul R.; Nebl, Thomas; Hanssen, Eric; Berriman, Matthew; Chan, Jo-Anne; Blanch, Adam J.; Beeson, James G.; Rayner, Julian C.; Przyborski, Jude M.; Tilley, Leann; Crabb, Brendan S.

    2017-01-01

    Malaria is caused by five different Plasmodium spp. in humans each of which modifies the host erythrocyte to survive and replicate. The two main causes of malaria, P. falciparum and P. vivax, differ in their ability to cause severe disease, mainly due to differences in the cytoadhesion of infected erythrocytes (IE) in the microvasculature. Cytoadhesion of P. falciparum in the brain leads to a large number of deaths each year and is a consequence of exported parasite proteins, some of which modify the erythrocyte cytoskeleton while others such as PfEMP1 project onto the erythrocyte surface where they bind to endothelial cells. Here we investigate the effects of knocking out an exported Hsp70-type chaperone termed Hsp70-x that is present in P. falciparum but not P. vivax. Although the growth of Δhsp70-x parasites was unaffected, the export of PfEMP1 cytoadherence proteins was delayed and Δhsp70-x IE had reduced adhesion. The Δhsp70-x IE were also more rigid than wild-type controls indicating changes in the way the parasites modified their host erythrocyte. To investigate the cause of this, transcriptional and translational changes in exported and chaperone proteins were monitored and some changes were observed. We propose that PfHsp70-x is not essential for survival in vitro, but may be required for the efficient export and functioning of some P. falciparum exported proteins. PMID:28732045

  10. Adenoviral transfer of HSP-70 into pulmonary epithelium ameliorates experimental acute respiratory distress syndrome.

    Science.gov (United States)

    Weiss, Yoram G; Maloyan, Alina; Tazelaar, John; Raj, Nichelle; Deutschman, Clifford S

    2002-09-01

    The acute respiratory distress syndrome (ARDS) provokes three pathologic processes: unchecked inflammation, interstitial/alveolar protein accumulation, and destruction of pulmonary epithelial cells. The highly conserved heat shock protein HSP-70 can limit all three responses but is not appropriately expressed in the lungs after cecal ligation and double puncture (2CLP), a clinically relevant model of ARDS. We hypothesize that restoring expression of HSP-70 using adenovirus-mediated gene therapy will limit pulmonary pathology following 2CLP. We administered a vector containing the porcine HSP-70 cDNA driven by a CMV promoter (AdHSP) into the lungs of rats subjected to 2CLP or sham operation. Administration of AdHSP after either sham operation or 2CLP increased HSP-70 protein expression in lung tissue, as determined by immunohistochemistry and Western blot hybridization. Administration of AdHSP significantly attenuated interstitial and alveolar edema and protein exudation and dramatically decreased neutrophil accumulation, relative to a control adenovirus. CLP-associated mortality at 48 hours was reduced by half. Modulation of HSP-70 production reduces pathologic changes and may improve outcome in experimental ARDS.

  11. DNA double strand breaks and Hsp70 expression in proton irradiated living cells

    International Nuclear Information System (INIS)

    Fiedler, Anja; Reinert, Tilo; Tanner, Judith; Butz, Tilman

    2007-01-01

    DNA double strand breaks (DSBs) in living cells can be directly provoked by ionising radiation. DSBs can be visualized by immunostaining the phosphorylated histone γH2AX. Our concern was to test the feasibility of γH2AX staining for a direct visualization of single proton hits. If single protons produce detectable foci, DNA DSBs could be used as 'biological track detectors' for protons. Ionising radiation can also damage proteins indirectly by inducing free radicals. Heat shock proteins (Hsp) help to refold or even degrade the damaged proteins. The level of the most famous heat shock protein Hsp70 is increased by ionising radiation. We investigated the expression of γH2AX and Hsp70 after cross and line patterned irradiation with counted numbers of 2.25 MeV protons on primary human skin fibroblasts. The proton induced DSBs appear more delocalised than it was expected by the ion hit accuracy. Cooling the cells before the irradiation reduces the delocalisation of DNA DSBs, which is probably caused by the reduced diffusion of DNA damaging agents. Proton irradiation seems to provoke protein damages mainly in the cytoplasm indicated by cytoplasmic Hsp70 aggregates. On the contrary, in control heat shocked cells the Hsp70 was predominantly localized in the cell nucleus. However, the irradiated area could not be recognized, all cells on the Si 3 N 4 window showed a homogenous Hsp70 expression pattern

  12. DNA double strand breaks and Hsp70 expression in proton irradiated living cells

    Energy Technology Data Exchange (ETDEWEB)

    Fiedler, Anja [Institute for Experimental Physics II, University of Leipzig (Germany) and Faculty of Biology, Pharmacy and Psychology, University of Leipzig (Germany)]. E-mail: afiedler@uni-leipzig.de; Reinert, Tilo [Institute for Experimental Physics II, University of Leipzig (Germany); Tanner, Judith [Clinic and Polyclinic for Radiation Oncology, University of Halle-Wittenberg (Germany); Butz, Tilman [Institute for Experimental Physics II, University of Leipzig (Germany)

    2007-07-15

    DNA double strand breaks (DSBs) in living cells can be directly provoked by ionising radiation. DSBs can be visualized by immunostaining the phosphorylated histone {gamma}H2AX. Our concern was to test the feasibility of {gamma}H2AX staining for a direct visualization of single proton hits. If single protons produce detectable foci, DNA DSBs could be used as 'biological track detectors' for protons. Ionising radiation can also damage proteins indirectly by inducing free radicals. Heat shock proteins (Hsp) help to refold or even degrade the damaged proteins. The level of the most famous heat shock protein Hsp70 is increased by ionising radiation. We investigated the expression of {gamma}H2AX and Hsp70 after cross and line patterned irradiation with counted numbers of 2.25 MeV protons on primary human skin fibroblasts. The proton induced DSBs appear more delocalised than it was expected by the ion hit accuracy. Cooling the cells before the irradiation reduces the delocalisation of DNA DSBs, which is probably caused by the reduced diffusion of DNA damaging agents. Proton irradiation seems to provoke protein damages mainly in the cytoplasm indicated by cytoplasmic Hsp70 aggregates. On the contrary, in control heat shocked cells the Hsp70 was predominantly localized in the cell nucleus. However, the irradiated area could not be recognized, all cells on the Si{sub 3}N{sub 4} window showed a homogenous Hsp70 expression pattern.

  13. Induction of hsp70 by the herbicide oxyfluorfen (Goal) in the Egyptian Nile fish, Oreochromis niloticus.

    Science.gov (United States)

    Hassanein, H M; Banhawy, M A; Soliman, F M; Abdel-Rehim, S A; Müller, W E; Schröder, H C

    1999-07-01

    This paper deals with the expression of the biomarker hsp70 in the liver and kidney of the freshwater fish Oreochromis niloticus following exposure to the herbicide oxyfluorfen (Goal). Fishes were exposed to three concentrations, the 96-h LC50 (3 mg/L), the 96-h (1/2)LC50 (1.5 mg/L), and the 96-h (1/4)LC50 (0.75 mg/L) of oxyfluorfen for 6, 15, and 24 days, respectively, and samples were taken at three different time periods for each concentration. The livers responded to the herbicide by an induction of the expression of both the constitutive (hsp75; Mr 75 kDa) and the inducible (hsp73; Mr 73 kDa) hsp70 proteins. In kidney, the herbicide induced a time-dependent increase in the expression of the constitutive hsp70 (hsp75) as well, but the inducible hsp70 (hsp73) required much longer incubation periods to reach maximal levels (15 and 24 days). Our results suggest that expression of hsp70 in fish is a sensitive indicator of cellular responses to herbicide exposure in the aquatic environment.

  14. [The impact of melafen on the expression of chloroplastic chaperone protein HSP70B and photosynthetic pigments in cells of Chlamydomonas reinhardtii].

    Science.gov (United States)

    Ermokhina, O V; Belkina, G G; Oleskina, Iu P; Fattakhov, S G; Iurina, N P

    2009-01-01

    The effects of growth regulator of the new generation-melamine salt of bis(oxymethyl)phosphine acid (melafen)--on culture growth, pigment and protein content, and the induction of protective chloroplastic chaperone HSP70B in Chlamydomonas reinhardtii CW15 cells were studied. Melafen exhibited 10-30% growth inhibition at 10(-9)-10(-2)% concentration. At 10(-9)-10(-4)% of melafen electrophoretic concentration, the pattern of cellular proteins was similar to the control. The alterations in protein content of algae cells were detected only at 10(-2)% concentration. The content of chlorophyll and carotenoids in melafen-treated cells was 17-40% lower than in the control. Melafen at 10(-9)-109-2)% concentration inhibited HSP70B induction by 39-43% compared to untreated cells. The potential mechanism of melafen effect might involve its influence on nuclear gene expression.

  15. Structure of a new crystal form of human Hsp70 ATPase domain.

    Science.gov (United States)

    Osipiuk, J; Walsh, M A; Freeman, B C; Morimoto, R I; Joachimiak, A

    1999-05-01

    Hsp70 proteins are highly conserved proteins induced by heat shock and other stress conditions. An ATP-binding domain of human Hsp70 protein has been crystallized in two major morphological forms at pH 7.0 in the presence of PEG 8000 and CaCl2. Both crystal forms belong to the orthorhombic space group P212121, but show no resemblance in unit-cell parameters. Analysis of the crystal structures for both forms shows a 1-2 A shift of one of the subdomains of the protein. This conformational change could reflect a 'natural' flexibility of the protein which might be relevant to ATP binding and may facilitate the interaction of other proteins with Hsp70 protein.

  16. HSP70 expression in the copper butterfly Lycaena tityrus across altitudes and temperatures

    DEFF Research Database (Denmark)

    Karl, I.; Sørensen, Jesper Givskov; Loeschcke, Volker

    2009-01-01

    temperatures show differences in HSP70 expression. HSP70 expression increased substantially at the higher rearing temperature in low-altitude butterflies, which might represent an adaptation to occasionally occurring heat spells. On the other hand, high-altitude butterflies showed much less plasticity...... in response to rearing temperatures, and overall seem to rely more on genetically fixed thermal stress resistance. Whether the latter indicates a higher vulnerability of high-altitude populations to global warming needs further investigation. HSP70 expression increased with both colder and warmer induction......The ability to express heat-shock proteins (HSP) under thermal stress is an essential mechanism for ectotherms to cope with unfavourable conditions. In this study, we investigate if Copper butterflies originating from different altitudes and/or being exposed to different rearing and induction...

  17. Real-time observation of the conformational dynamics of mitochondrial Hsp70 by spFRET.

    Science.gov (United States)

    Sikor, Martin; Mapa, Koyeli; von Voithenberg, Lena Voith; Mokranjac, Dejana; Lamb, Don C

    2013-05-29

    The numerous functions of the important class of molecular chaperones, heat shock proteins 70 (Hsp70), rely on cycles of intricate conformational changes driven by ATP-hydrolysis and regulated by cochaperones and substrates. Here, we used Förster resonance energy transfer to study the conformational dynamics of individual molecules of Ssc1, a mitochondrial Hsp70, in real time. The intrinsic dynamics of the substrate-binding domain of Ssc1 was observed to be uncoupled from the dynamic interactions between substrate- and nucleotide-binding domains. Analysis of the fluctuations in the interdomain separation revealed frequent transitions to a nucleotide-free state. The nucleotide-exchange factor Mge1 did not induce ADP release, as expected, but rather facilitated binding of ATP. These results indicate that the conformational cycle of Ssc1 is more elaborate than previously thought and provide insight into how the Hsp70s can perform a wide variety of functions.

  18. Enhancement of Hsp70 synthesis protects common carp, Cyprinus carpio L., against lethal ammonia toxicity.

    Science.gov (United States)

    Sung, Y Y; Roberts, R J; Bossier, P

    2012-08-01

    Exposure to TEX-OE®, a patented extract of the prickly pear cactus (Opuntia ficus indica) containing chaperone-stimulating factor, was shown to protect common carp, Cyprinus carpio L., fingerlings against acute ammonia stress. Survival was enhanced twofold from 50% to 95% after exposure to 5.92 mg L(-1) NH(3) , a level determined in the ammonia challenge bioassay as the 1-h LD50 concentration for this species. Survival of TEX-OE®-pre-exposed fish was enhanced by 20% over non-exposed controls during lethal ammonia challenge (14.21 mg L(-1)  NH(3) ). Increase in the levels of gill and muscle Hsp70 was evident in TEX-OE®-pre-exposed fish but not in the unexposed controls, indicating that application of TEX-OE® accelerated carp endogenous Hsp70 synthesis during ammonia perturbation. Protection against ammonia was correlated with Hsp70 accretion. © 2012 Blackwell Publishing Ltd.

  19. Increased HSF activation in muscles with a high constitutive Hsp70 expression

    OpenAIRE

    Locke, Marius; Tanguay, Robert M.

    1996-01-01

    Stress-induced transcriptional regulation of the Hsps is mediated by trimerization and binding of a pre-existing heat shock transcription factor (HSF1) to a specific DNA sequence located in the 5′ region of hsp genes, known as the heat shock element. Hsp70 has been implicated in regulating the activation of the HSF and, according to cell culture models, high steady-state levels of Hsp70 are inversely correlated with HSF activation. To determine if this applies in an intact animal, muscles of ...

  20. Conserved effects of salinity acclimation on thermal tolerance and hsp70 expression in divergent populations of threespine stickleback (Gasterosteus aculeatus).

    Science.gov (United States)

    Metzger, David C H; Healy, Timothy M; Schulte, Patricia M

    2016-10-01

    In natural environments, organisms must cope with complex combinations of abiotic stressors. Here, we use threespine stickleback (Gasterosteus aculeatus) to examine how changes in salinity affect tolerance of high temperatures. Threespine stickleback inhabit a range of environments that vary in both salinity and thermal stability making this species an excellent system for investigating interacting stressors. We examined the effects of environmental salinity on maximum thermal tolerance (CTMax) and 70 kDa heat shock protein (hsp70) gene expression using divergent stickleback ecotypes from marine and freshwater habitats. In both ecotypes, the CTMax of fish acclimated to 20 ppt was significantly higher compared to fish acclimated to 2 ppt. The effect of salinity acclimation on the expression of hsp70-1 and hsp70-2 was similar in both the marine and freshwater stickleback ecotype. There were differences in the expression profiles of hsp70-1 and hsp70-2 during heat shock, with hsp70-2 being induced earlier and to a higher level compared to hsp70-1. These data suggest that the two hsp70 isoforms may have functionally different roles in the heat shock response. Lastly, acute salinity challenge coupled with heat shock revealed that the osmoregulatory demands experienced during the heat shock response have a larger effect on the hsp70 expression profile than does the acclimation salinity.

  1. Plasmodium falciparum Hep1 Is Required to Prevent the Self Aggregation of PfHsp70-3.

    Directory of Open Access Journals (Sweden)

    David O Nyakundi

    Full Text Available The majority of mitochondrial proteins are encoded in the nucleus and need to be imported from the cytosol into the mitochondria, and molecular chaperones play a key role in the efficient translocation and proper folding of these proteins in the matrix. One such molecular chaperone is the eukaryotic mitochondrial heat shock protein 70 (Hsp70; however, it is prone to self-aggregation and requires the presence of an essential zinc-finger protein, Hsp70-escort protein 1 (Hep1, to maintain its structure and function. PfHsp70-3, the only Hsp70 predicted to localize in the mitochondria of P. falciparum, may also rely on a Hep1 orthologue to prevent self-aggregation. In this study, we identified a putative Hep1 orthologue in P. falciparum and co-expression of PfHsp70-3 and PfHep1 enhanced the solubility of PfHsp70-3. PfHep1 suppressed the thermally induced aggregation of PfHsp70-3 but not the aggregation of malate dehydrogenase or citrate synthase, thus showing specificity for PfHsp70-3. Zinc ions were indeed essential for maintaining the function of PfHep1, as EDTA chelation abrogated its abilities to suppress the aggregation of PfHsp70-3. Soluble and functional PfHsp70-3, acquired by co-expression with PfHep-1, will facilitate the biochemical characterisation of this particular Hsp70 protein and its evaluation as a drug target for the treatment of malaria.

  2. Expression dynamics of HSP70 during chronic heat stress in Tharparkar cattle.

    Science.gov (United States)

    Bharati, Jaya; Dangi, S S; Chouhan, V S; Mishra, S R; Bharti, M K; Verma, V; Shankar, O; Yadav, V P; Das, K; Paul, A; Bag, S; Maurya, V P; Singh, G; Kumar, P; Sarkar, M

    2017-06-01

    Six male Tharparkar cattle aged 2-3 years were selected for the study. The animals were acclimatized in the psychrometric chamber at thermoneutral zone (TNZ) for 15 days and then exposed to 42 °C temperature up to 23 days followed by 12 days of recovery period. Physiological responses were estimated, and peripheral blood mononuclear cells (PBMCs) were isolated at TNZ on day 1, day 5, and day 12; after 6 h of heat stress exposure on day 16 to day 20, day 25, day 30, day 32, day 34, day 36, and day 38; and a recovery period on day 45 and day 50. The PBMCs were cultured to study the effect of thermal challenge on HSP70 messenger RNA (mRNA) expression pattern at different temperature-time combinations. The mRNA and protein expression of HSP70 in PBMCs along with serum extracellular HSP70 (eHSP70) was increased (P cattle and the biphasic expression pattern may be providing a second window of protection during chronic heat stress.

  3. Leishmania infantum HSP70-II null mutant as candidate vaccine against leishmaniasis: a preliminary evaluation

    Directory of Open Access Journals (Sweden)

    Fresno Manuel

    2011-07-01

    Full Text Available Abstract Background Visceral leishmaniasis is the most severe form of leishmaniasis and no effective vaccine exists. The use of live attenuated vaccines is emerging as a promising vaccination strategy. Results In this study, we tested the ability of a Leishmania infantum deletion mutant, lacking both HSP70-II alleles (ΔHSP70-II, to provide protection against Leishmania infection in the L. major-BALB/c infection model. Administration of the mutant line by either intraperitoneal, intravenous or subcutaneous route invariably leads to the production of high levels of NO and the development in mice of type 1 immune responses, as determined by analysis of anti-Leishmania IgG subclasses. In addition, we have shown that ΔHSP70-II would be a safe live vaccine as immunodeficient SCID mice, and hamsters (Mesocricetus auratus, infected with mutant parasites did not develop any sign of pathology. Conclusions The results suggest that the ΔHSP70-II mutant is a promising and safe vaccine, but further studies in more appropriate animal models (hamsters and dogs are needed to appraise whether this attenuate mutant would be useful as vaccine against visceral leishmaniasis.

  4. Expression profiling of Plasmodium berghei HSP70 genes for generation of bright red fluorescent parasites.

    Directory of Open Access Journals (Sweden)

    Marion Hliscs

    Full Text Available Live cell imaging of recombinant malarial parasites encoding fluorescent probes provides critical insights into parasite-host interactions and life cycle progression. In this study, we generated a red fluorescent line of the murine malarial parasite Plasmodium berghei. To allow constitutive and abundant expression of the mCherry protein we profiled expression of all members of the P. berghei heat shock protein 70 (HSP70 family. We identified PbHSP70/1, an invariant ortholog of Plasmodium falciparum HSP70-1, as the protein with the highest expression levels during Plasmodium blood, mosquito, and liver infection. Stable allelic insertion of a mCherry expression cassette into the PbHsp70/1 locus created constitutive red fluorescent P. berghei lines, termed Pbred. We show that these parasites can be used for live imaging of infected host cells and organs, including hepatocytes, erythrocytes, and whole Anopheles mosquitoes. Quantification of the fluorescence intensity of several Pbred parasite stages revealed significantly enhanced signal intensities in comparison to GFP expressed under the control of the constitutive EF1alpha promoter. We propose that systematic transcript profiling permits generation of reporter parasites, such as the Pbred lines described herein.

  5. Identification and Characterization of a Novel Human Methyltransferase Modulating Hsp70 Protein Function through Lysine Methylation*

    Science.gov (United States)

    Jakobsson, Magnus E.; Moen, Anders; Bousset, Luc; Egge-Jacobsen, Wolfgang; Kernstock, Stefan; Melki, Ronald; Falnes, Pål Ø.

    2013-01-01

    Hsp70 proteins constitute an evolutionarily conserved protein family of ATP-dependent molecular chaperones involved in a wide range of biological processes. Mammalian Hsp70 proteins are subject to various post-translational modifications, including methylation, but for most of these, a functional role has not been attributed. In this study, we identified the methyltransferase METTL21A as the enzyme responsible for trimethylation of a conserved lysine residue found in several human Hsp70 (HSPA) proteins. This enzyme, denoted by us as HSPA lysine (K) methyltransferase (HSPA-KMT), was found to catalyze trimethylation of various Hsp70 family members both in vitro and in vivo, and the reaction was stimulated by ATP. Furthermore, we show that HSPA-KMT exclusively methylates 70-kDa proteins in mammalian protein extracts, demonstrating that it is a highly specific enzyme. Finally, we show that trimethylation of HSPA8 (Hsc70) has functional consequences, as it alters the affinity of the chaperone for both the monomeric and fibrillar forms of the Parkinson disease-associated protein α-synuclein. PMID:23921388

  6. Association of eNOS and HSP70 gene polymorphisms with glaucoma in Pakistani cohorts.

    NARCIS (Netherlands)

    Ayub, H.; Khan, M.I.; Micheal, S.; Akhtar, F.; Ajmal, M.; Shafique, S.; Ali, S.H.; Hollander, A.I. den; Ahmed, A.; Qamar, R.

    2010-01-01

    PURPOSE: To investigate the involvement of stress-regulating genes, endothelial nitric oxide synthase (eNOS) and heat shock protein 70 (HSP70) with primary open angle glaucoma (POAG) and primary closed angle glaucoma (PCAG). METHODS: POAG and PCAG patients recruited from different areas of Pakistan

  7. Identification and characterization of cytosolic Hansenula polymorpha proteins belonging to the Hsp70 protein family

    NARCIS (Netherlands)

    Titorenko, Vladimir I.; Evers, Melchior E.; Diesel, Andre; Samyn, Bart; Beeumen, Josef van; Roggenkamp, Rainer; Kiel, Jan A.K.W.; Klei, Ida J. van der; Veenhuis, Marten

    We have isolated two members of the Hsp70 protein family from the yeast Hansenula polymorpha using affinity chromatography. Both proteins were located in the cytoplasm. One of these, designated Hsp72, was inducible in nature (e.g. by heat shock). The second protein (designated Hsc74) was

  8. Hsp70 and ceramide release by diode laser-treated mouse skin cells in vivo

    Science.gov (United States)

    Sokolovskii, G. S.; Onikienko, S. B.; Zemlyanoi, A. V.; Soboleva, K. K.; Pikhtin, N. A.; Tarasov, I. S.; Guzova, I. V.; Margulis, B. A.

    2014-12-01

    We report experimental study of generation of extracellular heat shock proteins (Hsp70) and ceramides under pulsed irradiation by quantum-well laser diodes. Our results are of great promise for applications in practical medicine such as protection against biopathogenes and abiotic stress factor challenges.

  9. [Antiarrhythmic effect of oligonucleotides accompanied by activation of HSP70 protein in the heart of rats].

    Science.gov (United States)

    Kruglov, S V; Terekhina, O L; Smirnova, E A; Kashaeva, O V; Belkina, L M

    2015-01-01

    The mechanisms of the protective effect of oligonucleotides (OGN) during pathological processes are poorlyunderstood. The goal of this work was to study the effect of OGN on arrhythmias induced by myocardial ischemia and reperfusion, and the HSP70 level in the heart. As a source of OGN was used the drug "Derinat" ("Technomedservis", Russia). In male Wistar rats were pre-treated the drug for 7 days (i/m, 7.5 mg/kg).The intensity of the arrhythmias was assessed by ECG during 10 min occlusion of the left coronary artery and subsequent 5 min of reperfusion. Protein HSP70 determined in the left ventricle of the heart by Western-blot analysis. During ischemia, this drug reduced duration of extrasystolia by 13 times and the incidence of ventricular tachycardia by 1.5 times. During reperfusion the drug reduced the incidence of ventricular fibrillation, a more than 2-fold, as compared with the control (respectively 23% vs 56%) and by 5 times its duration (8,4 ± 2,3 48,1 ± sec vs 18 7 sec). "Derinat" increased the HSP70 level in the heart by 65% compared with control. These data support the fact that the activation of HSP70 synthesis, induced by OGN is one of the mechanisms that increases the heart resistance to the ischemic and reperfusion damages.

  10. Cytosine deletion at AP2-box region of HSP70 promoter and its ...

    Indian Academy of Sciences (India)

    Cytosine deletion at AP2-box region of HSP70 promoter and its influence on semen quality traits in crossbred bulls ... Laboratory, ICAR-Central Institute for Research on Cattle, Meerut 250 001, India; School of Atmospheric Stress Management, ICAR-National Institute of Abiotic Stress Management, Baramati 413 115, India ...

  11. Species- and Strain-Specific Adaptation of the HSP70 Super Family in Pathogenic Trypanosomatids

    Czech Academy of Sciences Publication Activity Database

    Drini, S.; Criscuolo, A.; Lechat, P.; Imamura, H.; Skalický, Tomáš; Rachidi, N.; Lukeš, Julius; Dujardin, J.-C.; Späth, G.F.

    2016-01-01

    Roč. 8, č. 6 (2016), s. 1980-1995 ISSN 1759-6653 R&D Projects: GA ČR(CZ) GA14-23986S Institutional support: RVO:60077344 Keywords : Leishmania * heat shock protein * HSP70 * evolution * phylogeny * synteny * copy number variation * gene lossgene loss Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.979, year: 2016

  12. Molecular mechanism of allosteric communication in Hsp70 revealed by molecular dynamics simulations.

    Directory of Open Access Journals (Sweden)

    Federica Chiappori

    Full Text Available Investigating ligand-regulated allosteric coupling between protein domains is fundamental to understand cell-life regulation. The Hsp70 family of chaperones represents an example of proteins in which ATP binding and hydrolysis at the Nucleotide Binding Domain (NBD modulate substrate recognition at the Substrate Binding Domain (SBD. Herein, a comparative analysis of an allosteric (Hsp70-DnaK and a non-allosteric structural homolog (Hsp110-Sse1 of the Hsp70 family is carried out through molecular dynamics simulations, starting from different conformations and ligand-states. Analysis of ligand-dependent modulation of internal fluctuations and local deformation patterns highlights the structural and dynamical changes occurring at residue level upon ATP-ADP exchange, which are connected to the conformational transition between closed and open structures. By identifying the dynamically responsive protein regions and specific cross-domain hydrogen-bonding patterns that differentiate Hsp70 from Hsp110 as a function of the nucleotide, we propose a molecular mechanism for the allosteric signal propagation of the ATP-encoded conformational signal.

  13. Congenital sideroblastic anemia due to mutations in the mitochondrial HSP70 homologue HSPA9

    DEFF Research Database (Denmark)

    Schmitz-Abe, Klaus; Ciesielski, Szymon J.; Schmidt, Paul J.

    2015-01-01

    The congenital sideroblastic anemias (CSAs) are relatively uncommon diseases characterized by defects in mitochondrial heme synthesis, iron-sulfur (Fe-S) cluster biogenesis, or protein synthesis. Here we demonstrate that mutations in HSPA9, a mitochondrial HSP70 homolog located in the chromosome 5q...

  14. The effect of glutamine infusion on the inflammatory response and HSP70 during human experimental endotoxaemia

    DEFF Research Database (Denmark)

    Andreasen, Anne Sofie; Pedersen-Skovsgaard, Theis; Mortensen, Ole Hartvig

    2009-01-01

    was associated with alterations in white blood cell and differential counts, tumour necrosis factor-alpha, IL-6, temperature and heart rate, but glutamine affected neither the endotoxin-induced change in these variables nor the expression of HSP70 in BMNCs. CONCLUSIONS: Endotoxin reduced plasma glutamine...

  15. Genome-wide analysis of the Hsp70 family genes in pepper (Capsicum annuum L.) and functional identification of CaHsp70-2 involvement in heat stress.

    Science.gov (United States)

    Guo, Meng; Liu, Jin-Hong; Ma, Xiao; Zhai, Yu-Fei; Gong, Zhen-Hui; Lu, Ming-Hui

    2016-11-01

    Hsp70s function as molecular chaperones and are encoded by a multi-gene family whose members play a crucial role in plant response to stress conditions, and in plant growth and development. Pepper (Capsicum annuum L.) is an important vegetable crop whose genome has been sequenced. Nonetheless, no overall analysis of the Hsp70 gene family is reported in this crop plant to date. To assess the functionality of Capsicum annuum Hsp70 (CaHsp70) genes, pepper genome database was analyzed in this research. A total of 21 CaHsp70 genes were identified and their characteristics were also described. The promoter and transcript expression analysis revealed that CaHsp70s were involved in pepper growth and development, and heat stress response. Ectopic expression of a cytosolic gene, CaHsp70-2, regulated expression of stress-related genes and conferred increased thermotolerance in transgenic Arabidopsis. Taken together, our results provide the basis for further studied to dissect CaHsp70s' function in response to heat stress as well as other environmental stresses. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  16. Heritability of hsp70 expression in the beetle Tenebrio molitor: Ontogenetic and environmental effects.

    Science.gov (United States)

    Lardies, Marco A; Arias, María Belén; Poupin, María Josefina; Bacigalupe, Leonardo D

    2014-08-01

    Ectotherms constitute the vast majority of terrestrial biodiversity and are especially likely to be vulnerable to climate warming because their basic physiological functions such as locomotion, growth, and reproduction are strongly influenced by environmental temperature. An integrated view about the effects of global warming will be reached not just establishing how the increase in mean temperature impacts the natural populations but also establishing the effects of the increase in temperature variance. One of the molecular responses that are activated in a cell under a temperature stress is the heat shock protein response (HSP). Some studies that have detected consistent differences among thermal treatments and ontogenetic stages in HSP70 expression have assumed that these differences had a genetic basis and consequently expression would be heritable. We tested for changes in quantitative genetic parameters of HSP70 expression in a half-sib design where individuals of the beetle Tenebrio molitor were maintained in constant and varying thermal environments. We estimated heritability of HSP70 expression using a linear mixed modelling approach in different ontogenetic stages. Expression levels of HSP70 were consistently higher in the variable environment and heritability estimates were low to moderate. The results imply that within each ontogenetic stage additive genetic variance was higher in the variable environment and in adults compared with constant environment and larvae stage, respectively. We found that almost all the genetic correlations across ontogenetic stages and environment were positive. These suggest that directional selection for higher levels of expression in one environment will result in higher expression levels of HSP70 on the other environment for the same ontogenetic stage. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. Concerted and nonconcerted evolution of the Hsp70 gene superfamily in two sibling species of nematodes.

    Science.gov (United States)

    Nikolaidis, Nikolas; Nei, Masatoshi

    2004-03-01

    We have identified the Hsp70 gene superfamily of the nematode Caenorhabditis briggsae and investigated the evolution of these genes in comparison with Hsp70 genes from C. elegans, Drosophila, and yeast. The Hsp70 genes are classified into three monophyletic groups according to their subcellular localization, namely, cytoplasm (CYT), endoplasmic reticulum (ER), and mitochondria (MT). The Hsp110 genes can be classified into the polyphyletic CYT group and the monophyletic ER group. The different Hsp70 and Hsp110 groups appeared to evolve following the model of divergent evolution. This model can also explain the evolution of the ER and MT genes. On the other hand, the CYT genes are divided into heat-inducible and constitutively expressed genes. The constitutively expressed genes have evolved more or less following the birth-and-death process, and the rates of gene birth and gene death are different between the two nematode species. By contrast, some heat-inducible genes show an intraspecies phylogenetic clustering. This suggests that they are subject to sequence homogenization resulting from gene conversion-like events. In addition, the heat-inducible genes show high levels of sequence conservation in both intra-species and inter-species comparisons, and in most cases, amino acid sequence similarity is higher than nucleotide sequence similarity. This indicates that purifying selection also plays an important role in maintaining high sequence similarity among paralogous Hsp70 genes. Therefore, we suggest that the CYT heat-inducible genes have been subjected to a combination of purifying selection, birth-and-death process, and gene conversion-like events.

  18. Association of plasma IL-6 and Hsp70 with HRV at different levels of PAHs metabolites.

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    Jian Ye

    Full Text Available Exposure to polycyclic aromatic hydrocarbons (PAHs is associated with reduced heart rate variability (HRV, a strong predictor of cardiovascular diseases, but the mechanism is not well understood.We hypothesized that PAHs might induce systemic inflammation and stress response, contributing to altered cardiac autonomic function.HRV indices were measured using a 3-channel digital Holter monitor in 800 coke oven workers. Plasma levels of interleukin-6 (IL-6 and heat shock protein 70 (Hsp70 were determined using ELISA. Twelve urinary PAHs metabolites (OH-PAHs were measured by gas chromatography-mass spectrometry.We found that significant dose-dependent relationships between four urinary OH-PAHs and IL-6 (all Ptrend<0.05; and an increase in quartiles of IL-6 was significantly associated with a decrease in total power (TP and low frequency (LF (Ptrend = 0.014 and 0.006, respectively. In particular, elevated IL-6 was associated in a dose-dependent manner with decreased TP and LF in the high-PAHs metabolites groups (all Ptrend<0.05, but not in the low-PAHs metabolites groups. No significant association between Hsp70 and HRV in total population was found after multivariate adjustment. However, increased Hsp70 was significantly associated with elevated standard deviation of NN intervals (SDNN, TP and LF in the low-PAHs metabolites groups (all Ptrend<0.05. We also observed that both IL-6 and Hsp70 significantly interacted with multiple PAHs metabolites in relation to HRV.In coke oven workers, increased IL-6 was associated with a dose-response decreased HRV in the high-PAHs metabolites groups, whereas increase of Hsp70 can result in significant dose-related increase in HRV in the low-PAHs metabolites groups.

  19. Critical analysis of eukaryotic phylogeny: a case study based on the HSP70 family.

    Science.gov (United States)

    Germot, A; Philippe, H

    1999-01-01

    Trichomonads, together with diplomonads and microsporidia, emerge at the base of the eukaryotic tree, on the basis of the small subunit rRNA phylogeny. However, phylogenies based on protein sequences such as tubulin are markedly different with these protists emerging much later. We have investigated 70 kDa heat-shock protein (HSP70), which could be a reliable phylogenetic marker. In eukaryotes, HSP70s are found in cytosol, endoplasmic reticulum, and organelles (mitochondria and chloroplasts). In Trichomonas vaginalis we identified nine different HSP70-encoding genes and sequenced three nearly complete cDNAs corresponding to cytosolic, endoplasmic reticulum, and mitochondrial-type HSP70. Phylogenies of eukaryotes were reconstructed using the classical methods while varying the number of species and characters considered. Almost all the undoubtedly monophyletic groups, defined by ultrastructural characters, were recovered. However, due to the long branch attraction phenomenon, the evolutionary rates were the main factor determining the position of species, even with the use of a close outgroup, which is an important advantage of HSP70 with respect to many other markers. Numerous variable sites are peculiar to Trichomonas and probably generated the artefactual placement of this species at the base of the eukaryotes or as the sister group of fast-evolving species. The inter-phyla relationships were not well supported and were sensitive to the reconstruction method, the number of species; and the quantity of information used. This lack of resolution could be explained by the very rapid diversification of eukaryotes, likely after the mitochondrial endosymbiosis.

  20. A Novel Strategy for TNF-Alpha Production by 2-APB Induced Downregulated SOCE and Upregulated HSP70 in O. tsutsugamushi-Infected Human Macrophages.

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    Ching-Ying Wu

    Full Text Available Orientia (O. tsutsugamushi-induced scrub typhus is endemic across many regions of Asia and the Western Pacific, where an estimated 1 million cases occur each year; the majority of patients infected with O. tsutsugamushi end up with a cytokine storm from a severe inflammatory response. Previous reports have indicated that blocking tumor necrosis factor (TNF-α reduced cell injury from a cytokine storm. Since TNF-α production is known to be associated with intracellular Ca2+ elevation, we examined the effect of store-operated Ca2+ entry (SOCE inhibitors on TNF-α production in O. tsutsugamushi-infected macrophages. We found that 2-aminoethoxydiphenyl borate (2-APB, but not SKF96365, facilitates the suppression of Ca2+ mobilization via the interruption of Orai1 expression in O. tsutsugamushi-infected macrophages. Due to the decrease of Ca2+ elevation, the expression of TNF-α and its release from macrophages was repressed by 2-APB. In addition, a novel role of 2-APB was found in macrophages that causes the upregulation of heat shock protein 70 (HSP70 expression associated with ERK activation; upregulated TNF-α production in the case of knockdown HSP70 was inhibited with 2-APB treatment. Furthermore, elevated HSP70 formation unexpectedly did not help the cell survival of O. tsutsugamushi-infected macrophages. In conclusion, the parallelism between downregulated Ca2+ mobilization via SOCE and upregulated HSP70 after treatment with 2-APB against TNF-α production was found to efficiently attenuate an O. tsutsugamushi-induced severe inflammatory response.

  1. Adult Heat Tolerance Variation in Drosophila melanogaster is Not Related to Hsp70 Expression

    DEFF Research Database (Denmark)

    Jensen, Louise Toft; Cockerell, Fiona Elizabeth; Kristensen, Torsten Nygaard

    2010-01-01

    in Drosophila larvae Hsp70 expression may be a key determinant of heat tolerance, the evidence for this in adults is equivocal. We therefore examined heat-induced Hsp70 expression and several measurements of adult heat tolerance in three independent collections of D. melanogaster, measured in three laboratories...

  2. Organization and evolution of hsp70 clusters strikingly differ in two species of Stratiomyidae (Diptera inhabiting thermally contrasting environments

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    Bettencourt Brian R

    2011-03-01

    Full Text Available Abstract Background Previously, we described the heat shock response in dipteran species belonging to the family Stratiomyidae that develop in thermally and chemically contrasting habitats including highly aggressive ones. Although all species studied exhibit high constitutive levels of Hsp70 accompanied by exceptionally high thermotolerance, we also detected characteristic interspecies differences in heat shock protein (Hsp expression and survival after severe heat shock. Here, we analyzed genomic libraries from two Stratiomyidae species from thermally and chemically contrasting habitats and determined the structure and organization of their hsp70 clusters. Results Although the genomes of both species contain similar numbers of hsp70 genes, the spatial distribution of hsp70 copies differs characteristically. In a population of the eurytopic species Stratiomys singularior, which exists in thermally variable and chemically aggressive (hypersaline conditions, the hsp70 copies form a tight cluster with approximately equal intergenic distances. In contrast, in a population of the stenotopic Oxycera pardalina that dwells in a stable cold spring, we did not find hsp70 copies in tandem orientation. In this species, the distance between individual hsp70 copies in the genome is very large, if they are linked at all. In O. pardalina we detected the hsp68 gene located next to a hsp70 copy in tandem orientation. Although the hsp70 coding sequences of S. singularior are highly homogenized via conversion, the structure and general arrangement of the hsp70 clusters are highly polymorphic, including gross aberrations, various deletions in intergenic regions, and insertion of incomplete Mariner transposons in close vicinity to the 3'-UTRs. Conclusions The hsp70 gene families in S. singularior and O. pardalina evolved quite differently from one another. We demonstrated clear evidence of homogenizing gene conversion in the S. singularior hsp70 genes, which form

  3. Mitochondrial-type hsp70 genes of the amitochondriate protists, Giardia intestinalis, Entamoeba histolytica and two microsporidians☆

    Science.gov (United States)

    Arisue, Nobuko; Sánchez, Lidya B.; Weiss, Louis M.; Müller, Miklós; Hashimoto, Tetsuo

    2011-01-01

    Genes encoding putative mitochondrial-type heat shock protein 70 (mit-hsp70) were isolated and sequenced from amitochondriate protists, Giardia intestinalis, Entamoeba histolytica, and two microsporidians, Encephalitozoon hellem and Glugea plecoglossi. The deduced mit-hsp70 sequences were analyzed by sequence alignments and phylogenetic reconstructions. The mit-hsp70 sequence of these four amitochondriate protists were divergent from other mit-hsp70 sequences of mitochondriate eukaryotes. However, all of these sequences were clearly located within a eukaryotic mitochondrial clade in the tree including various type hsp70 sequences, supporting the emerging notion that none of these amitochondriate lineages are primitively amitochodrial, but lost their mitochondria secondarily in their evolutionary past. PMID:11880223

  4. The Malarial Exported PFA0660w Is an Hsp40 Co-Chaperone of PfHsp70-x.

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    Michael O Daniyan

    Full Text Available Plasmodium falciparum, the human pathogen responsible for the most dangerous malaria infection, survives and develops in mature erythrocytes through the export of proteins needed for remodelling of the host cell. Molecular chaperones of the heat shock protein (Hsp family are prominent members of the exportome, including a number of Hsp40s and a Hsp70. PFA0660w, a type II Hsp40, has been shown to be exported and possibly form a complex with PfHsp70-x in the infected erythrocyte cytosol. However, the chaperone properties of PFA0660w and its interaction with human and parasite Hsp70s are yet to be investigated. Recombinant PFA0660w was found to exist as a monomer in solution, and was able to significantly stimulate the ATPase activity of PfHsp70-x but not that of a second plasmodial Hsp70 (PfHsp70-1 or a human Hsp70 (HSPA1A, indicating a potential specific functional partnership with PfHsp70-x. Protein binding studies in the presence and absence of ATP suggested that the interaction of PFA0660w with PfHsp70-x most likely represented a co-chaperone/chaperone interaction. Also, PFA0660w alone produced a concentration-dependent suppression of rhodanese aggregation, demonstrating its chaperone properties. Overall, we have provided the first biochemical evidence for the possible role of PFA0660w as a chaperone and as co-chaperone of PfHsp70-x. We propose that these chaperones boost the chaperone power of the infected erythrocyte, enabling successful protein trafficking and folding, and thereby making a fundamental contribution to the pathology of malaria.

  5. Loss of the inducible Hsp70 delays the inflammatory response to skeletal muscle injury and severely impairs muscle regeneration.

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    Sarah M Senf

    Full Text Available Skeletal muscle regeneration following injury is a highly coordinated process that involves transient muscle inflammation, removal of necrotic cellular debris and subsequent replacement of damaged myofibers through secondary myogenesis. However, the molecular mechanisms which coordinate these events are only beginning to be defined. In the current study we demonstrate that Heat shock protein 70 (Hsp70 is increased following muscle injury, and is necessary for the normal sequence of events following severe injury induced by cardiotoxin, and physiological injury induced by modified muscle use. Indeed, Hsp70 ablated mice showed a significantly delayed inflammatory response to muscle injury induced by cardiotoxin, with nearly undetected levels of both neutrophil and macrophage markers 24 hours post-injury. At later time points, Hsp70 ablated mice showed sustained muscle inflammation and necrosis, calcium deposition and impaired fiber regeneration that persisted several weeks post-injury. Through rescue experiments reintroducing Hsp70 intracellular expression plasmids into muscles of Hsp70 ablated mice either prior to injury or post-injury, we confirm that Hsp70 optimally promotes muscle regeneration when expressed during both the inflammatory phase that predominates in the first four days following severe injury and the regenerative phase that predominates thereafter. Additional rescue experiments reintroducing Hsp70 protein into the extracellular microenvironment of injured muscles at the onset of injury provides further evidence that Hsp70 released from damaged muscle may drive the early inflammatory response to injury. Importantly, following induction of physiological injury through muscle reloading following a period of muscle disuse, reduced inflammation in 3-day reloaded muscles of Hsp70 ablated mice was associated with preservation of myofibers, and increased muscle force production at later time points compared to WT. Collectively our

  6. Cell type-specific variations in the induction of hsp70 in human leukocytes by feverlike whole body hyperthermia.

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    Oehler, R; Pusch, E; Zellner, M; Dungel, P; Hergovics, N; Homoncik, M; Eliasen, M M; Brabec, M; Roth, E

    2001-10-01

    Fever has been associated with shortened duration and improved survival in infectious disease. The mechanism of this beneficial response is still poorly understood. The heat-inducible 70-kDa heat shock protein (Hsp70) has been associated with protection of leukocytes against the cytotoxicity of inflammatory mediators and with improved survival of severe infections. This study characterizes the induction of Hsp70 by feverlike temperatures in human leukocytes in vitro and in vivo. Using flow cytometry, Hsp70 expression was determined in whole blood samples. This approach eliminated cell isolation procedures that would greatly affect the results. Heat treatment of whole blood in vitro for 2 hours at different temperatures revealed that Hsp70 expression depends on temperature and cell type; up to 41 degrees C, Hsp70 increased only slightly in lymphocytes and polymorphonuclear leukocytes. However, in monocytes a strong induction was already seen at 39 degrees C, and Hsp70 levels at 41 degrees C were 10-fold higher than in the 37 degrees C control. To be as close as possible to the physiological situation during fever, we immersed healthy volunteers in a hot water bath, inducing whole body hyperthermia (39 degrees C), and measured leukocyte Hsp70 expression. Hsp70 was induced in all leukocytes with comparable but less pronounced cell type-specific variations as observed in vitro. Thus, a systemic increase of body temperature as triggered by fever stimulates Hsp70 expression in peripheral leukocytes, especially in monocytes. This fever-induced Hsp70 expression may protect monocytes when confronted with cytotoxic inflammatory mediators, thereby improving the course of the disease.

  7. Human Hsp70 molecular chaperone binds two calcium ions within the ATPase domain.

    Science.gov (United States)

    Sriram, M; Osipiuk, J; Freeman, B; Morimoto, R; Joachimiak, A

    1997-03-15

    The 70 kDa heat shock proteins (Hsp70) are a family of molecular chaperones, which promote protein folding and participate in many cellular functions. The Hsp70 chaperones are composed of two major domains. The N-terminal ATPase domain binds to and hydrolyzes ATP, whereas the C-terminal domain is required for polypeptide binding. Cooperation of both domains is needed for protein folding. The crystal structure of bovine Hsc70 ATPase domain (bATPase) has been determined and, more recently, the crystal structure of the peptide-binding domain of a related chaperone, DnaK, in complex with peptide substrate has been obtained. The molecular chaperone activity and conformational switch are functionally linked with ATP hydrolysis. A high-resolution structure of the ATPase domain is required to provide an understanding of the mechanism of ATP hydrolysis and how it affects communication between C- and N-terminal domains. The crystal structure of the human Hsp70 ATPase domain (hATPase) has been determined and refined at 1. 84 A, using synchrotron radiation at 120K. Two calcium sites were identified: the first calcium binds within the catalytic pocket, bridging ADP and inorganic phosphate, and the second calcium is tightly coordinated on the protein surface by Glu231, Asp232 and the carbonyl of His227. Overall, the structure of hATPase is similar to bATPase. Differences between them are found in the loops, the sites of amino acid substitution and the calcium-binding sites. Human Hsp70 chaperone is phosphorylated in vitro in the presence of divalent ions, calcium being the most effective. The structural similarity of hATPase and bATPase and the sequence similarity within the Hsp70 chaperone family suggest a universal mechanism of ATP hydrolysis among all Hsp70 molecular chaperones. Two calcium ions have been found in the hATPase structure. One corresponds to the magnesium site in bATPase and appears to be important for ATP hydrolysis and in vitro phosphorylation. Local changes

  8. Regulation of Hsp27 and Hsp70 expression in human and mouse skin construct models by caveolae following exposure to the model sulfur mustard vesicant, 2-chloroethyl ethyl sulfide

    International Nuclear Information System (INIS)

    Black, Adrienne T.; Hayden, Patrick J.; Casillas, Robert P.; Heck, Diane E.; Gerecke, Donald R.; Sinko, Patrick J.; Laskin, Debra L.; Laskin, Jeffrey D.

    2011-01-01

    Dermal exposure to the vesicant sulfur mustard causes marked inflammation and tissue damage. Basal keratinocytes appear to be a major target of sulfur mustard. In the present studies, mechanisms mediating skin toxicity were examined using a mouse skin construct model and a full-thickness human skin equivalent (EpiDerm-FT TM ). In both systems, administration of the model sulfur mustard vesicant, 2-chloroethyl ethyl sulfide (CEES, 100-1000 μM) at the air surface induced mRNA and protein expression of heat shock proteins 27 and 70 (Hsp27 and Hsp70). CEES treatment also resulted in increased expression of caveolin-1, the major structural component of caveolae. Immunohistochemistry revealed that Hsp27, Hsp70 and caveolin-1 were localized in basal and suprabasal layers of the epidermis. Caveolin-1 was also detected in fibroblasts in the dermal component of the full thickness human skin equivalent. Western blot analysis of caveolar membrane fractions isolated by sucrose density centrifugation demonstrated that Hsp27 and Hsp70 were localized in caveolae. Treatment of mouse keratinocytes with filipin III or methyl-β-cyclodextrin, which disrupt caveolar structure, markedly suppressed CEES-induced Hsp27 and Hsp70 mRNA and protein expression. CEES treatment is known to activate JNK and p38 MAP kinases; in mouse keratinocytes, inhibition of these enzymes suppressed CEES-induced expression of Hsp27 and Hsp70. These data suggest that MAP kinases regulate Hsp 27 and Hsp70; moreover, caveolae-mediated regulation of heat shock protein expression may be important in the pathophysiology of vesicant-induced skin toxicity.

  9. Recombinant TgHSP70 Immunization Protects against Toxoplasma gondii Brain Cyst Formation by Enhancing Inducible Nitric Oxide Expression

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    Neide M. Silva

    2017-04-01

    Full Text Available Toxoplasma gondii is known to cause congenital infection in humans and animals and severe disease in immunocompromised individuals; consequently development of vaccines against the parasite is highly necessary. Under stress conditions, T. gondii expresses the highly immunogenic heat shock protein 70 (TgHSP70. Here, we assessed the protective efficacy of rTgHSP70 immunization combined with Alum in oral ME-49 T. gondii infection and the mechanisms involved on it. It was observed that immunized mice with rTgHSP70 or rTgHSP70 adsorbed in Alum presented a significantly reduced number of cysts in the brain that was associated with increased iNOS+ cell numbers in the organ, irrespective the use of the adjuvant. Indeed, ex vivo experiments showed that peritoneal macrophages pre-stimulated with rTgHSP70 presented increased NO production and enhanced parasite killing, and the protein was able to directly stimulate B cells toward antibody producing profile. In addition, rTgHSP70 immunization leads to high specific antibody titters systemically and a mixed IgG1/IgG2a response, with predominance of IgG1 production. Nonetheless, it was observed that the pretreatment of the parasite with rTgHSP70 immune sera was not able to control T. gondii internalization and replication by NIH fibroblast neither peritoneal murine macrophages, nor anti-rTgHSP70 antibodies were able to kill T. gondii by complement-mediated lysis, suggesting that these mechanisms are not crucial to resistance. Interestingly, when in combination with Alum, rTgHSP70 immunization was able to reduce inflammation in the brain of infected mice and in parallel anti-rTgHSP70 immune complexes in the serum. In conclusion, immunization with rTgHSP70 induces massive amounts of iNOS expression and reduced brain parasitism, suggesting that iNOS expression and consequently NO production in the brain is a protective mechanism induced by TgHSP70 immunization, therefore rTgHSP70 can be a good candidate for

  10. Encoded novel forms of HSP70 or a cytolytic protein increase DNA vaccine potency.

    Science.gov (United States)

    Garrod, Tamsin; Grubor-Bauk, Branka; Yu, Stanley; Gargett, Tessa; Gowans, Eric J

    2014-01-01

    In humans, DNA vaccines have failed to demonstrate the equivalent levels of immunogenicity that were shown in smaller animals. Previous studies have encoded adjuvants, predominantly cytokines, within these vaccines in an attempt to increase antigen-specific immune responses. However, these strategies have lacked breadth of innate immune activation and have led to disappointing results in clinical trials. Damage associated molecular patterns (DAMPs) have been identified as pattern recognition receptor (PRR) agonists. DAMPs can bind to a wide range of PRRs on dendritic cells (DCs) and thus our studies have aimed to utilize this characteristic to act as an adjuvant in a DNA vaccine approach. Specifically, HSP70 has been identified as a DAMP, but has been limited by its lack of accessibility to PRRs in and on DCs. Here, we discuss the promising results achieved with the inclusion of membrane-bound or secreted HSP70 into a DNA vaccine encoding HIV gag as the model immunogen.

  11. A toxic imbalance of Hsp70s in Saccharomyces cerevisiae is caused by competition for cofactors.

    Science.gov (United States)

    Keefer, Kathryn M; True, Heather L

    2017-09-01

    Molecular chaperones are responsible for managing protein folding from translation through degradation. These crucial machines ensure that protein homeostasis is optimally maintained for cell health. However, 'too much of a good thing' can be deadly, and the excess of chaperones can be toxic under certain cellular conditions. For example, overexpression of Ssa1, a yeast Hsp70, is toxic to cells in folding-challenged states such as [PSI+]. We discovered that overexpression of the nucleotide exchange factor Sse1 can partially alleviate this toxicity. We further argue that the basis of the toxicity is related to the availability of Hsp70 cofactors, such as Hsp40 J-proteins and nucleotide exchange factors. Ultimately, our work informs future studies about functional chaperone balance and cautions against therapeutic chaperone modifications without a thorough examination of cofactor relationships. © 2017 John Wiley & Sons Ltd.

  12. Hsp70 Expression Profile in Preeclampsia Model of Pregnant Rat (Rattus norvegicus) after Giving the EVOO

    Science.gov (United States)

    Irianti, E.; ilyas, S.; Rosidah; Hutahaean, S.

    2017-03-01

    Heat shock protein (Hsp) has long been known to protect cells from oxidative stress. In this case an increased expression is found on several cases of preeclampsia. One of the efforts to prevent preeclampsia is by giving antioxidants such as Extra Virgin Olive Oil (EVOO) or it’s better known as olive oil (Oleoa europaea), in the form of extra virgin known for its rich antioxidant content of tocopherols (vitamin E). The purpose of this study is to determine the expression levels of Hsp70 serum on pregnant white rat model of preeclampsia after being given EVOO. This type of research is true experiment; the subjects were female white rats and male virgin with Sprague Dawley, ± 8-11 weeks old, 180g BB s / d 200g, healthy and didn’t show any physical defects. Samples were 25 animals, divided into 5 groups, which consisted of different control and treatment given to T2 (rat model of preeclampsia), T3 (rat model of preeclampsia + EVOO 0.45g/bw/day), T4 (rat model of preeclampsia + EVOO 0.9g/bw/day) and T5 (rat model of preeclampsia + EVOO 1.8g/bw/day). The determination of each group was done by simple random sampling. Result on serum levels of Hsp70 that were tested by Elisa test in rats showed the average control was 14.64 mg / ml, group T2: 22:51 mg/ml, T3: 13.62 mg/ml, T4: 15.92 mg/ml, T5: 16:09 mg/ml. ANOVA test showed the P value was 0.001 <0.005, which meant there were significant differences on serum Hsp70 levels in the control and treatment pregnant rats group. It was known that there was a significant difference level of Hsp70 serum in group of control rats with T2 (P value <0.001) after LSD test was conducted, but not so with the group T3, T4, and T5, where the difference was not significant. There was a significant difference in the levels of Hsp70 serum on group T2 and T3 (P value 0.000), T4 (0004), T5 (0000). The gift of EVOO in the treatment group which was given EVOO with even low doses was able to control the induction of Hsp70 serum levels, which

  13. Model of Oxygen and Glucose Deprivation in PC12 Cells and Detection of HSP70 Protein

    Science.gov (United States)

    He, Jinting; Yang, Le; Shao, Yankun

    2018-01-01

    Objective: PC12 cell was used to set up a ischemia model by OGD and detected HSP70 protein. Methods: Use of PC12 cells induced by NGF stimulation into nerve cells, oxygen and glucose deprivation to build the nerve cells of oxygen and glucose deprivation model; using Western blot analysis of PC12 cells into neuron-like cells and oxygen-glucose deprivation model established. Results: The application of a final concentration of 50 ng / ml of NGF in DMEM complete mediumPC12 cells showed a typical neuronal morphology with the increase in cell culture time. NGF culture time showed a positive correlation, the establishment of oxygen and glucose deprivation (OGD) training environment, the OGD after nerve element appears different degrees of damage, OGD can effectively induce the expression of HSP70. Conclusion: PC12 cell transformed into cells by NGF; the cell model of OGD was established.

  14. Examination the expression pattern of HSP70 heat shock protein in chicken PGCs and developing genital ridge

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    Mahek Anand

    2016-05-01

    Full Text Available Chicken Primordial Germ cells (PGCs are emerging pioneers in the field of applied embryology and stem cell technology. Now-a-days transgenic chickens are promising models to study human disease pathophysiology and drug designing. However, most of the molecular mechanism, which govern the stemness and pluripotency of chicken PGCs, not known in details. Recent studies have indicated the role of HSP70 in early embryonic development in many vertebrate species. Exposure of chicken to heat stress result in activation of heat shock factors which activate the transcription of HSP70. Exposure chicken eggs to acute heat stress effects HSP70 expression in PGCs and gonads. HSP70 helps in maintaining the integrity of chicken PGCs. A new emerging role of HSP70 in apoptosis has emerged. In our lab, we aim to characterize the expression of cHsp70 in chicken PGCs and gonads during embryonic development by subjecting the parents to acute levels of heat stress. Chickens whose parents subjected to heat stress showed varied expression of cHsp70 and also improved thermo tolerance. In the future we plan to study other factors and miRNAs, which is characterized as an emerging player in regulating heat shock protein response in chicken and also plays an important role in apoptosis.

  15. secHsp70 as a tool to approach amyloid-β42 and other extracellular amyloids.

    Science.gov (United States)

    De Mena, Lorena; Chhangani, Deepak; Fernandez-Funez, Pedro; Rincon-Limas, Diego E

    2017-07-03

    Self-association of amyloidogenic proteins is the main pathological trigger in a wide variety of neurodegenerative disorders. These aggregates are deposited inside or outside the cell due to hereditary mutations, environmental exposures or even normal aging. Cumulative evidence indicates that the heat shock chaperone Hsp70 possesses robust neuroprotection against various intracellular amyloids in Drosophila and mouse models. However, its protective role against extracellular amyloids was largely unknown as its presence outside the cells is very limited. Our recent manuscript in PNAS revealed that an engineered form of secreted Hsp70 (secHsp70) is highly protective against toxicity induced by extracellular deposition of the amyloid-β42 (Aβ42) peptide. In this Extra View article, we extend our analysis to other members of the heat shock protein family. We created PhiC31-based transgenic lines for human Hsp27, Hsp40, Hsp60 and Hsp70 and compared their activities in parallel against extracellular Aβ42. Strikingly, only secreted Hsp70 exhibits robust protection against Aβ42-triggered toxicity in the extracellular milieu. These observations indicate that the ability of secHsp70 to suppress Aβ42 insults is quite unique and suggest that targeted secretion of Hsp70 may represent a new therapeutic approach against Aβ42 and other extracellular amyloids. The potential applications of this engineered chaperone are discussed.

  16. Progranulin Recruits HSP70 to β-Glucocerebrosidase and Is Therapeutic Against Gaucher Disease.

    Science.gov (United States)

    Jian, Jinlong; Tian, Qing-Yun; Hettinghouse, Aubryanna; Zhao, Shuai; Liu, Helen; Wei, Jianlu; Grunig, Gabriele; Zhang, Wujuan; Setchell, Kenneth D R; Sun, Ying; Overkleeft, Herman S; Chan, Gerald L; Liu, Chuan-Ju

    2016-11-01

    Gaucher disease (GD), the most common lysosomal storage disease, is caused by mutations in GBA1 encoding of β-glucocerebrosidase (GCase). Recently it was reported that progranulin (PGRN) insufficiency and deficiency associated with GD in human and mice, respectively. However the underlying mechanisms remain unknown. Here we report that PGRN binds directly to GCase and its deficiency results in aggregation of GCase and its receptor LIMP2. Mass spectrometry approaches identified HSP70 as a GCase/LIMP2 complex-associated protein upon stress, with PGRN as an indispensable adaptor. Additionally, 98 amino acids of C-terminal PGRN, referred to as Pcgin, are required and sufficient for the binding to GCase and HSP70. Pcgin effectively ameliorates the disease phenotype in GD patient fibroblasts and animal models. These findings not only demonstrate that PGRN is a co-chaperone of HSP70 and plays an important role in GCase lysosomal localization, but may also provide new therapeutic interventions for lysosomal storage diseases, in particular GD. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

  17. Progranulin Recruits HSP70 to β-Glucocerebrosidase and Is Therapeutic Against Gaucher Disease

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    Jinlong Jian

    2016-11-01

    Full Text Available Gaucher disease (GD, the most common lysosomal storage disease, is caused by mutations in GBA1 encoding of β-glucocerebrosidase (GCase. Recently it was reported that progranulin (PGRN insufficiency and deficiency associated with GD in human and mice, respectively. However the underlying mechanisms remain unknown. Here we report that PGRN binds directly to GCase and its deficiency results in aggregation of GCase and its receptor LIMP2. Mass spectrometry approaches identified HSP70 as a GCase/LIMP2 complex-associated protein upon stress, with PGRN as an indispensable adaptor. Additionally, 98 amino acids of C-terminal PGRN, referred to as Pcgin, are required and sufficient for the binding to GCase and HSP70. Pcgin effectively ameliorates the disease phenotype in GD patient fibroblasts and animal models. These findings not only demonstrate that PGRN is a co-chaperone of HSP70 and plays an important role in GCase lysosomal localization, but may also provide new therapeutic interventions for lysosomal storage diseases, in particular GD.

  18. Development of a microarray-based assay for efficient testing of new HSP70/DnaK inhibitors.

    Science.gov (United States)

    Mohammadi-Ostad-Kalayeh, Sona; Hrupins, Vjaceslavs; Helmsen, Sabine; Ahlbrecht, Christin; Stahl, Frank; Scheper, Thomas; Preller, Matthias; Surup, Frank; Stadler, Marc; Kirschning, Andreas; Zeilinger, Carsten

    2017-12-15

    A facile method for testing ATP binding in a highly miniaturized microarray environment using human HSP70 and DnaK from Mycobacterium tuberculosis as biological targets is reported. Supported by molecular modelling studies we demonstrate that the position of the fluorescence label on ATP has a strong influence on the binding to human HSP70. Importantly, the label has to be positioned on the adenine ring and not to the terminal phosphate group. Unlabelled ATP displaced bound Cy5-ATP from HSP70 in the micromolar range. The affinity of a well-known HSP70 inhibitor VER155008 for the ATP binding site in HSP70 was determined, with a EC 50 in the micromolar range, whereas reblastin, a HSP90-inhibitor, did not compete for ATP in the presence of HSP70. The applicability of the method was demonstrated by screening a small compound library of natural products. This unraveled that terphenyls rickenyl A and D, recently isolated from cultures of the fungus Hypoxylon rickii, are inhibitors of HSP70. They compete with ATP for the chaperone in the range of 29 µM (Rickenyl D) and 49 µM (Rickenyl A). Furthermore, the microarray-based test system enabled protein-protein interaction analysis using full-length HSP70 and HSP90 proteins. The labelled full-length human HSP90 binds with a half-maximal affinity of 5.5 µg/ml (∼40 µM) to HSP70. The data also demonstrate that the microarray test has potency for many applications from inhibitor screening to target-oriented interaction studies. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Anaplasma phagocytophilum MSP4 and HSP70 Proteins Are Involved in Interactions with Host Cells during Pathogen Infection

    Directory of Open Access Journals (Sweden)

    Marinela Contreras

    2017-07-01

    Full Text Available Anaplasma phagocytophilum transmembrane and surface proteins play a role during infection and multiplication in host neutrophils and tick vector cells. Recently, A. phagocytophilum Major surface protein 4 (MSP4 and Heat shock protein 70 (HSP70 were shown to be localized on the bacterial membrane, with a possible role during pathogen infection in ticks. In this study, we hypothesized that A. phagocytophilum MSP4 and HSP70 have similar functions in tick-pathogen and host-pathogen interactions. To address this hypothesis, herein we characterized the role of these bacterial proteins in interaction and infection of vertebrate host cells. The results showed that A. phagocytophilum MSP4 and HSP70 are involved in host-pathogen interactions, with a role for HSP70 during pathogen infection. The analysis of the potential protective capacity of MSP4 and MSP4-HSP70 antigens in immunized sheep showed that MSP4-HSP70 was only partially protective against pathogen infection. This limited protection may be associated with several factors, including the recognition of non-protective epitopes by IgG in immunized lambs. Nevertheless, these antigens may be combined with other candidate protective antigens for the development of vaccines for the control of human and animal granulocytic anaplasmosis. Focusing on the characterization of host protective immune mechanisms and protein-protein interactions at the host-pathogen interface may lead to the discovery and design of new effective protective antigens.

  20. B-chromosome effects on Hsp70 gene expression does not occur at transcriptional level in the grasshopper Eyprepocnemis plorans.

    Science.gov (United States)

    Navarro-Domínguez, Beatriz; Cabrero, Josefa; Camacho, Juan Pedro M; López-León, María Dolores

    2016-10-01

    As intragenomic parasites, B chromosomes can elicit stress in the host genome, thus inducing a response for host adaptation to this kind of continuous parasitism. In the grasshopper Eyprepocnemis plorans, B-chromosome presence has been previously associated with a decrease in the amount of the heat-shock protein 70 (HSP70). To investigate whether this effect is already apparent at transcriptional level, we analyze the expression levels of the Hsp70 gene in gonads and somatic tissues of males and females with and without B chromosomes from two populations, where the predominant B chromosome variants (B2 and B24) exhibit different levels of parasitism, by means of quantitative real-time PCR (qPCR) on complementary DNA (cDNA). The results revealed the absence of significant differences for Hsp70 transcripts associated with B-chromosome presence in virtually all samples. This indicates that the decrease in HSP70 protein levels, formerly reported in this species, may not be a consequence of transcriptional down-regulation of Hsp70 genes, but the result of post-transcriptional regulation. These results will help to design future studies oriented to identifying factors modulating Hsp70 expression, and will also contribute to uncover the biological role of B chromosomes in eukaryotic genomes.

  1. Conformational Activation of Argonaute by Distinct yet Coordinated Actions of the Hsp70 and Hsp90 Chaperone Systems.

    Science.gov (United States)

    Tsuboyama, Kotaro; Tadakuma, Hisashi; Tomari, Yukihide

    2018-05-17

    Loading of small RNAs into Argonaute, the core protein in RNA silencing, requires the Hsp70/Hsp90 chaperone machinery. This machinery also activates many other clients, including steroid hormone receptors and kinases, but how their structures change during chaperone-dependent activation remains unclear. Here, we utilized single-molecule Förster resonance energy transfer (smFRET) to probe the conformational changes of Drosophila Ago2 mediated by the chaperone machinery. We found that empty Ago2 exists in various closed conformations. The Hsp70 system (Hsp40 and Hsp70) and the Hsp90 system (Hop, Hsp90, and p23) together render Ago2 into an open, active form. The Hsp70 system, but not the Hsp90 system alone, is sufficient for Ago2 to partially populate the open form. Instead, the Hsp90 system is required to extend the dwell time of Ago2 in the open state, which must be transiently primed by the Hsp70 system. Our data uncover distinct and coordinated actions of the chaperone machinery, where the Hsp70 system expands the structural ensembles of Ago2 and the Hsp90 system captures and stabilizes the active form. Copyright © 2018 Elsevier Inc. All rights reserved.

  2. Cadmium tolerance in seven Daphnia magna clones is associated with reduced hsp70 baseline levels and induction

    International Nuclear Information System (INIS)

    Haap, Timo; Koehler, Heinz-R.

    2009-01-01

    The stress protein hsp70 is part of the intracellular alarm and repair system which enables organisms to counteract negative effects of toxicants on protein integrity. Under long-term selection pressure exerted by environmental pollution, in particular heavy metals, this system may be expected to play a major role in the course of local, microevolutionary events leading to the acquisition of toxicant resistance. Seven clones of Daphnia magna from different geographical regions were characterized regarding their sensitivity to Cd, their hsp70 expression, and Cd accumulation. In an acute immobilisation assay, the tested clones showed remarkable differences in their sensitivity to Cd. The highest EC 50 values by far were obtained for the clone displaying lowest hsp70 expression. In general, hsp70 levels reflected the order of sensitivity to Cd among the seven clones reciprocally. Clonal variations in sensitivity and hsp70 expression could not be related to differential accumulation of Cd, though. In summary, the association of stress insensitivity with low hsp70 induction which has been exemplarily reported for populations of different invertebrates under strong selection pressure could be affirmed for a largely parthenogenetic species for the first time. Furthermore, our observation has serious consequences for the interpretation of toxicological assays using a single D. magna clone solely.

  3. Effects of Thermal Stress on the mRNA Expression of SOD, HSP90, and HSP70 in the Spotted Sea Bass ( Lateolabrax maculatus)

    Science.gov (United States)

    Shin, Moon-Kyeong; Park, Ho-Ra; Yeo, Won-Jun; Han, Kyung-Nam

    2018-03-01

    The aim of this study was to elucidate the molecular mechanisms underlying the thermal stress response in the spotted sea bass ( Lateolabrax maculatus). Spotted sea basses were exposed to 4 different water temperatures (20, 22, 24, and 28°C) in increasing increments of 2°C/h from 18°C (control) for different time periods (0, 6, 12, 24, 48, 72, and 96 h). Subsequently, 3 tissues (liver, muscle, and gill) were isolated, and the levels of SOD, HSP90, and HSP70 mRNA were assessed. SOD mRNA expression was maintained at baseline levels of control fish at all water temperatures in the liver, while muscle and gill tissue showed an increase followed by a decrease over each certain time with higher water temperature. HSP90 mRNA expression increased in the liver at ≤ 24°C over time, but maintained baseline expression at 28°C. In muscle, HSP90 mRNA expression gradually increased at all water temperatures, but increased and then decreased at ≥ 24°C in gill tissue. HSP70 mRNA expression exhibited an increase and then a decrease in liver tissue at 28°C, but mainly showed similar expression patterns to HSP90 in all tissues. These results suggest the activity of a defense mechanism using SOD, HSP90, and HSP70 in the spotted sea bass upon rapid increases in water temperature, where the expression of these genes indicated differences between tissues in the extent of the defense mechanisms. Also, these results indicate that high water temperature and long-term thermal stress exposure can inhibit physiological defense mechanisms.

  4. Hsp70 cochaperones HspBP1 and BAG-1M differentially regulate steroid hormone receptor function.

    Directory of Open Access Journals (Sweden)

    Regina T Knapp

    Full Text Available Hsp70 binding protein 1 (HspBP1 and Bcl2-associated athanogene 1 (BAG-1, the functional orthologous nucleotide exchange factors of the heat shock protein 70 kilodalton (Hsc70/Hsp70 chaperones, catalyze the release of ADP from Hsp70 while inducing different conformational changes of the ATPase domain of Hsp70. An appropriate exchange rate of ADP/ATP is crucial for chaperone-dependent protein folding processes. Among Hsp70 client proteins are steroid receptors such as the glucocorticoid receptor (GR, the mineralocorticoid receptor (MR, and the androgen receptor (AR. BAG-1 diversely affects steroid receptor activity, while to date the influence of HspBP1 on steroid receptor function is mostly unknown. Here, we compared the influence of HspBP1 and BAG-1M on Hsp70-mediated steroid receptor folding complexes and steroid receptor activity. Coimmunoprecipitation studies indicated preferential binding of Hsp40 and the steroid receptors to BAG-1M as compared to HspBP1. Furthermore, Hsp70 binding to the ligand-binding domain of GR was reduced in the presence of HspBP1 but not in the presence of BAG-1M as shown by pull-down assays. Reporter gene experiments revealed an inhibitory effect on GR, MR, and AR at a wide range of HspBP1 protein levels and at hormone concentrations at or approaching saturation. BAG-1M exhibited a transition from stimulatory effects at low BAG-1M levels to inhibitory effects at higher BAG-1M levels. Overall, BAG-1M and HspBP1 had differential impacts on the dynamic composition of steroid receptor folding complexes and on receptor function with important implications for steroid receptor physiology.

  5. Expression of HSP70 in cerebral ischemia and neuroprotetive action of hypothermia and ketoprofen Expressão de HSP70 na isquemia cerebral e a ação neuroprotetora da hipotermia e do cetoprofeno

    Directory of Open Access Journals (Sweden)

    Daniela Pretti da Cunha Tirapelli

    2010-08-01

    Full Text Available Heat shock proteins (HSPs are molecular chaperones that bind to other proteins to shepherd them across membranes and direct them to specific locations within a cell. Several injurious stimuli can induce Hsp70 expression, including ischemia. This study aimed to investigate the pattern of expression of protein (immunohistochemistry and gene (real-time PCR Hsp70 in experimental focal cerebral ischemia in rats by occlusion of the middle cerebral artery for 1 hour and the role of neuroprotection with hypothermia (H and ketoprofen (K. The infarct volume was measured using morphometric analysis defined by triphenyl tetrazolium chloride. It was observed increases in the protein (p=0.0001 and gene (p=0.0001 Hsp70 receptor in the ischemic areas that were reduced by H (protein and gene: pProteínas de choque térmico (HSPs são chaperones moleculares que se ligam a outras proteínas para atravessar as membranas e encaminhá-las para locais específicos dentro de uma célula. Vários estímulos nocivos podem induzir a expressão de Hsp70, incluindo isquemia. Este estudo teve como objetivo investigar o padrão de expressão protéica (imunohistoquímica e gênica (PCR em tempo real de Hsp70 na isquemia cerebral focal experimental em ratos pela oclusão da artéria cerebral média durante 1 hora e o papel da neuroproteção com hipotermia (H e cetoprofeno (C. O volume de infarto foi calculado através da análise morfométrica definido por cloreto de trifenil tetrazólio. Foi observado aumento na expressão proteína (p=0,0001 e gênica (p=0,0001 de Hsp70 nas áreas isquêmicas que foram reduzidas pela H (proteína e gene: p<0,05, C (proteína: p<0,001 e H+K (proteína: p<0,01 e gene: p<0,05. O aumento de Hsp70 na área isquêmica sugere que a neuroexcitotoxicidade mediada pela Hsp70 desempenha um papel importante na morte celular e que o efeito neuroprotetor tanto da H quanto do C está diretamente envolvido com a Hsp70.

  6. Cytosolic Hsp70/Hsc70 protein expression in lymphocytes exposed to low gamma-ray dose

    International Nuclear Information System (INIS)

    Manzanares A, E.; Vega C, H.R.; Letechipia de Leon, C.; Guzman E, L.J.; Garcia T, M.

    2004-01-01

    The purpose of this study was to evaluate the effect of low gamma ray intensity upon Hsp70 expression in human Iymphocytes. The heat shock proteins (Hsp) family, are a group of proteins present in all living organism, therefore there are highly conserved and are related to adaptation and evolution. At cellular level these proteins acts as chaperones correcting denatured proteins. When a stress agent, such heavy metals, UV, heat, etc. is affecting a cell a response to this aggression is triggered only through over expression of Hsp. Several studies has been carried out in which the cellular effect are observed, mostly of these studies uses large doses, but very few studies are related with low doses. Blood of healthy volunteers was obtained and the Iymphocytes were isolated by ficoll- histopaque gradient. Experimental lots were irradiated in a 137 Cs gamma-ray. Hsp70 expression was found since 0.5 c Gy, indicating a threshold to very low doses of gamma rays. (Author)

  7. Hsp70/Hsp90 organising protein (hop): beyond interactions with chaperones and prion proteins.

    Science.gov (United States)

    Baindur-Hudson, Swati; Edkins, Adrienne L; Blatch, Gregory L

    2015-01-01

    The Hsp70/Hsp90 organising protein (Hop), also known as stress-inducible protein 1 (STI1), has received considerable attention for diverse cellular functions in both healthy and diseased states. There is extensive evidence that intracellular Hop is a co-chaperone of the major chaperones Hsp70 and Hsp90, playing an important role in the productive folding of Hsp90 client proteins. Consequently, Hop is implicated in a number of key signalling pathways, including aberrant pathways leading to cancer. However, Hop is also secreted and it is now well established that Hop also serves as a receptor for the prion protein, PrP(C). The intracellular and extracellular forms of Hop most likely represent two different isoforms, although the molecular determinants of these divergent functions are yet to be identified. There is also a growing body of research that reports the involvement of Hop in cellular activities that appear independent of either chaperones or PrP(C). While Hop has been shown to have various cellular functions, its biological function remains elusive. However, recent knockout studies in mammals suggest that Hop has an important role in embryonic development. This review provides a critical overview of the latest molecular, cellular and biological research on Hop, critically evaluating its function in healthy systems and how this function is adapted in diseases states.

  8. Cytosolic Hsp70/Hsc70 protein expression in lymphocytes exposed to low gamma-ray dose

    Energy Technology Data Exchange (ETDEWEB)

    Manzanares A, E.; Vega C, H.R.; Letechipia de Leon, C. [Unidades Academicas de Estudios Nucleares, UAZ, A.P. 336, 98000 Zacatecas (Mexico)]. E-mail: emanz@cantera.reduaz.mx; Guzman E, L.J. [Unidad Academica de Biologia Experimental, Guadalupe, Zacatecas (Mexico); Garcia T, M. [LIBRA, Centro I and D, Campus Miguel Delibes, Valladolid 47011 (Spain)

    2004-07-01

    The purpose of this study was to evaluate the effect of low gamma ray intensity upon Hsp70 expression in human Iymphocytes. The heat shock proteins (Hsp) family, are a group of proteins present in all living organism, therefore there are highly conserved and are related to adaptation and evolution. At cellular level these proteins acts as chaperones correcting denatured proteins. When a stress agent, such heavy metals, UV, heat, etc. is affecting a cell a response to this aggression is triggered only through over expression of Hsp. Several studies has been carried out in which the cellular effect are observed, mostly of these studies uses large doses, but very few studies are related with low doses. Blood of healthy volunteers was obtained and the Iymphocytes were isolated by ficoll- histopaque gradient. Experimental lots were irradiated in a {sup 137} Cs gamma-ray. Hsp70 expression was found since 0.5 c Gy, indicating a threshold to very low doses of gamma rays. (Author)

  9. Jasmonate signalling in Arabidopsis involves SGT1b-HSP70-HSP90 chaperone complexes.

    Science.gov (United States)

    Zhang, Xue-Cheng; Millet, Yves A; Cheng, Zhenyu; Bush, Jenifer; Ausubel, Frederick M

    Plant hormones play pivotal roles in growth, development and stress responses. Although it is essential to our understanding of hormone signalling, how plants maintain a steady state level of hormone receptors is poorly understood. We show that mutation of the Arabidopsis thaliana co-chaperone SGT1b impairs responses to the plant hormones jasmonate, auxin and gibberellic acid, but not brassinolide and abscisic acid, and that SGT1b and its homologue SGT1a are involved in maintaining the steady state levels of the F-box proteins COI1 and TIR1, receptors for jasmonate and auxin, respectively. The association of SGT1b with COI1 is direct and is independent of the Arabidopsis SKP1 protein, ASK1. We further show that COI1 is a client protein of SGT1b-HSP70-HSP90 chaperone complexes and that the complexes function in hormone signalling by stabilizing the COI1 protein. This study extends the SGT1b-HSP90 client protein list and broadens the functional scope of SGT1b-HSP70-HSP90 chaperone complexes.

  10. Neurotherapeutic activity of the recombinant heat shock protein Hsp70 in a model of focal cerebral ischemia in rats

    Directory of Open Access Journals (Sweden)

    Shevtsov MA

    2014-05-01

    Full Text Available Maxim A Shevtsov,1,2 Boris P Nikolaev,3 Ludmila Y Yakovleva,3 Anatolii V Dobrodumov,4 Anastasiy S Dayneko,5 Alexey A Shmonin,5,6 Timur D Vlasov,5 Elena V Melnikova,5 Alexander D Vilisov,4,5 Irina V Guzhova,1 Alexander M Ischenko,3 Anastasiya L Mikhrina,7 Oleg V Galibin,5 Igor V Yakovenko,2 Boris A Margulis1 1Institute of Cytology of the Russian Academy of Sciences (RAS, St Petersburg, Russia; 2AL Polenov Russian Research Scientific Institute of Neurosurgery, St Petersburg, Russia; 3Research Institute of Highly Pure Biopreparations, St Petersburg, Russia; 4Institute of Macromolecular Compounds of the Russian Academy of Sciences (RAS, St Petersburg, Russia; 5First St Petersburg IP Pavlov State Medical University, St Petersburg, Russia; 6Federal Almazov Medical Research Centre, St Petersburg, Russia; 7IM Sechenov Institute of Evolutionary Physiology and Biochemistry of the Russian Academy of Sciences (RAS, St Petersburg, Russia Abstract: Recombinant 70 kDa heat shock protein (Hsp70 is an antiapoptotic protein that has a cell protective activity in stress stimuli and thus could be a useful therapeutic agent in the management of patients with acute ischemic stroke. The neuroprotective and neurotherapeutic activity of recombinant Hsp70 was explored in a model of experimental stroke in rats. Ischemia was produced by the occlusion of the middle cerebral artery for 45 minutes. To assess its neuroprotective capacity, Hsp70, at various concentrations, was intravenously injected 20 minutes prior to ischemia. Forty-eight hours after ischemia, rats were sacrificed and brain tissue sections were stained with 2% triphenyl tetrazolium chloride. Preliminary treatment with Hsp70 significantly reduced the ischemic zone (optimal response at 2.5 mg/kg. To assess Hsp70’s neurotherapeutic activity, we intravenously administered Hsp70 via the tail vein 2 hours after reperfusion (2 hours and 45 minutes after ischemia. Rats were then kept alive for 72 hours. The

  11. The Hsc/Hsp70 co-chaperone network controls antigen aggregation and presentation during maturation of professional antigen presenting cells.

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    Nadja Kettern

    Full Text Available The maturation of mouse macrophages and dendritic cells involves the transient deposition of ubiquitylated proteins in the form of dendritic cell aggresome-like induced structures (DALIS. Transient DALIS formation was used here as a paradigm to study how mammalian cells influence the formation and disassembly of protein aggregates through alterations of their proteostasis machinery. Co-chaperones that modulate the interplay of Hsc70 and Hsp70 with the ubiquitin-proteasome system (UPS and the autophagosome-lysosome pathway emerged as key regulators of this process. The chaperone-associated ubiquitin ligase CHIP and the ubiquitin-domain protein BAG-1 are essential for DALIS formation in mouse macrophages and bone-marrow derived dendritic cells (BMDCs. CHIP also cooperates with BAG-3 and the autophagic ubiquitin adaptor p62 in the clearance of DALIS through chaperone-assisted selective autophagy (CASA. On the other hand, the co-chaperone HspBP1 inhibits the activity of CHIP and thereby attenuates antigen sequestration. Through a modulation of DALIS formation CHIP, BAG-1 and HspBP1 alter MHC class I mediated antigen presentation in mouse BMDCs. Our data show that the Hsc/Hsp70 co-chaperone network controls transient protein aggregation during maturation of professional antigen presenting cells and in this way regulates the immune response. Similar mechanisms may modulate the formation of aggresomes and aggresome-like induced structures (ALIS in other mammalian cell types.

  12. Genetics of human longevity with emphasis on the relevance of HSP70 as candidate genes

    DEFF Research Database (Denmark)

    Singh, Ripudaman; Kølvrå, Steen; Rattan, Suresh I S

    2007-01-01

    Human longevity is determined to a certain extent by genetic factors. Several candidate genes have been studied for their association with human longevity, but the data collected so far are inconclusive. One of the reasons is the choice of the candidate genes in addition to the choice...... of an appropriate study design and methodology. Since aging is characterized by a progressive accumulation of molecular damage and an attenuation of the cellular defense mechanisms, the focus of studies on human longevity association with genes has now shifted to the pathways of cellular maintenance and repair...... mechanisms. One such pathway includes the battery of stress response genes, especially the heat shock protein HSP70 genes. Three such genes, HSPA1A, HSPA1B and HSPA1L, are present within the MHC-III region on the short arm of chromosome 6. We and others have found alleles, genotypes and haplotypes which have...

  13. Association of HSP70-2 Gene 1267A/G Polymorphism With Cataract Incidence Among Guilan Population

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    Zivar Salehi

    2017-01-01

    Full Text Available Background: Cataract is a visible opacity of the eye lens and it is the main reason of reversible blindness in the world. Oxidative stress is known as a major factor in cataract formation HSP70-2 protein is a molecular chaperone which is essential for cell survival in stress conditions. HSP70-2 gene is located in the human leukocyte antigen class ΙΙΙ region. This gene encodes an inducible protein. One of the common polymorphism of HSP70-2 is 1267A/G which is located in coding region. The aim of this study was to analysis of 1267A/G polymorphism of hsp70-2 gene in cataract patients. Material and Methods: This case-control study included 118 cataract patients and 122 healthy people as a control groups. Genomic DNA was extracted from peripheral blood leukocytes and genotyping determination was performed by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP method. Statistical analysis was performed by using the MedCalc software (Version 12.1. Results: The frequency of G allele was significantly higher in patients than the controls, (0.36 and 0.24, respectively. A higher frequency of the GG genotype of the HSP70-2 1267A/G polymorphism was found in the patients compared with controls (21.19% and 8.20%, respectively. The patients carrying the GG genotype were 3.2-fold at a higher risk of cataract compared with AA genotype (P=0.005. Conclusion: The finding of this study suggested that the HSP70-2 1267A/G may affect the susceptibility to cataract in the studied population. Anyway the randomized multicenter studies with greater sample size still need to confirmed our results.

  14. UV Radiation and Visible Light Induce hsp70 Gene Expression in the Antarctic Psychrophilic Ciliate Euplotes focardii.

    Science.gov (United States)

    Fulgentini, Lorenzo; Passini, Valerio; Colombetti, Giuliano; Miceli, Cristina; La Terza, Antonietta; Marangoni, Roberto

    2015-08-01

    The psychrophilic ciliate Euplotes focardii inhabits the shallow marine coastal sediments of Antarctica, where, over millions of years of evolution, it has reached a strict molecular adaptation to such a constant-temperature environment (about -2 °C). This long evolution at sub-zero temperatures has made E. focardii unable to respond to heat stress with the activation of its heat shock protein (hsp) 70 genes. These genes can, however, be expressed in response to other stresses, like the oxidative one, thus indicating that the molecular adaptation has exclusively altered the heat stress signaling pathways, while it has preserved hsp70 gene activation in response to other environmental stressors. Since radiative stress has proved to be affine to oxidative stress in several organisms, we investigated the capability of UV radiation to induce hsp70 transcription. E. focardii cell cultures were exposed to several different irradiation regimes, ranging from visible only to a mixture of visible, UV-A and UV-B. The irradiation values of each spectral band have been set to be comparable with those recorded in a typical Antarctic spring. Using Northern blot analysis, we measured the expression level of hsp70 immediately after irradiation (0-h-labeled samples), 1 h, and 2 h from the end of the irradiation. Surprisingly, our results showed that besides UV radiation, the visible light was also able to induce hsp70 expression in E. focardii. Moreover, spectrophotometric measurements have revealed no detectable endogenous pigments in E. focardii, making it difficult to propose a possible explanation for the visible light induction of its hsp70 genes. Further research is needed to conclusively clarify this point.

  15. Chaperone roles for TMAO and HSP70 during hyposmotic stress in the spiny dogfish shark (Squalus acanthias).

    Science.gov (United States)

    MacLellan, Robyn J; Tunnah, Louise; Barnett, David; Wright, Patricia A; MacCormack, Tyson; Currie, Suzanne

    2015-10-01

    Salinity decreases are experienced by many marine elasmobranchs. To understand how these fishes cope with hyposmotic stress on a cellular level, we used the spiny dogfish shark (Squalus acanthias) as a model to test whether a reciprocal relationship exists between the cell's two primary protein protection mechanisms, the chemical (e.g., trimethylamine oxide, TMAO) and molecular (e.g., heat shock protein 70, HSP70) chaperone systems. This relationship is interesting given that many elasmobranchs are expected to gain water and lose osmolytes, chemical chaperones, and ions as they osmoconform to new, lowered salinity. Dogfish were cannulated for repeated blood sampling and exposed to 70% seawater (SW) for 48 h. These hyposmotic conditions had no effect on red blood cell (RBC) and white muscle TMAO concentrations, and did not result in HSP70 induction or signs of protein damage (i.e., increased ubiquitin), suggesting that TMAO levels were sufficiently protective in these tissues. However, in the gill, we observed a significant decrease in TMAO concentration and a significant induction of HSP70 as well as signs of protein damage. In the face of this cellular stress response, gill Na(+)/K(+)-ATPase (NKA) activity significantly increased during hyposmotic conditions, as expected. We suggest that this functional preservation in the gill is partly the result of HSP70 induction with lowered salinity. We conclude a reciprocal relationship between TMAO and HSP70 in the gills of dogfish as a result of in vivo hyposmotic stress. When osmotically induced protein damage surpasses the protective capacity of remaining TMAO, HSP70 is induced to preserve tissue and organismal function.

  16. Ammonia stress under high environmental ammonia induces Hsp70 and Hsp90 in the mud eel, Monopterus cuchia.

    Science.gov (United States)

    Hangzo, Hnunlalliani; Banerjee, Bodhisattwa; Saha, Shrabani; Saha, Nirmalendu

    2017-02-01

    The obligatory air-breathing mud eel (Monopterus cuchia) is frequently being challenged with high environmental ammonia (HEA) exposure in its natural habitats. The present study investigated the possible induction of heat shock protein 70 and 90 (hsp70, hsc70, hsp90α and hsp90β) genes and more expression of Hsp70 and Hsp90 proteins under ammonia stress in different tissues of the mud eel after exposure to HEA (50 mM NH 4 Cl) for 14 days. HEA resulted in significant accumulation of toxic ammonia in different body tissues and plasma, which was accompanied with the stimulation of oxidative stress in the mud eel as evidenced by more accumulation of malondialdehyde (MDA) and hydrogen peroxide (H 2 O 2 ) during exposure to HEA. Further, hyper-ammonia stress led to significant increase in the levels of mRNA transcripts for inducible hsp70 and hsp90α genes and also their translated proteins in different tissues probably as a consequence of induction of hsp70 and hsp90α genes in the mud eel. However, hyper-ammonia stress was neither associated with any significant alterations in the levels of mRNA transcripts for constitutive hsc70 and hsp90β genes nor their translated proteins in any of the tissues studied. More abundance of Hsp70 and Hsp90α proteins might be one of the strategies adopted by the mud eel to defend itself from the ammonia-induced cellular damages under ammonia stress. Further, this is the first report of ammonia-induced induction of hsp70 and hsp90α genes under hyper-ammonia stress in any freshwater air-breathing teleost.

  17. Roles of intramolecular and intermolecular interactions in functional regulation of the Hsp70 J-protein co-chaperone Sis1.

    Science.gov (United States)

    Yu, Hyun Young; Ziegelhoffer, Thomas; Osipiuk, Jerzy; Ciesielski, Szymon J; Baranowski, Maciej; Zhou, Min; Joachimiak, Andrzej; Craig, Elizabeth A

    2015-04-10

    Unlike other Hsp70 molecular chaperones, those of the eukaryotic cytosol have four residues, EEVD, at their C-termini. EEVD(Hsp70) binds adaptor proteins of the Hsp90 chaperone system and mitochondrial membrane preprotein receptors, thereby facilitating processing of Hsp70-bound clients through protein folding and translocation pathways. Among J-protein co-chaperones functioning in these pathways, Sis1 is unique, as it also binds the EEVD(Hsp70) motif. However, little is known about the role of the Sis1:EEVD(Hsp70) interaction. We found that deletion of EEVD(Hsp70) abolished the ability of Sis1, but not the ubiquitous J-protein Ydj1, to partner with Hsp70 in in vitro protein refolding. Sis1 co-chaperone activity with Hsp70∆EEVD was restored upon substitution of a glutamic acid of the J-domain. Structural analysis revealed that this key glutamic acid, which is not present in Ydj1, forms a salt bridge with an arginine of the immediately adjacent glycine-rich region. Thus, restoration of Sis1 in vitro activity suggests that intramolecular interactions between the J-domain and glycine-rich region control co-chaperone activity, which is optimal only when Sis1 interacts with the EEVD(Hsp70) motif. However, we found that disruption of the Sis1:EEVD(Hsp70) interaction enhances the ability of Sis1 to substitute for Ydj1 in vivo. Our results are consistent with the idea that interaction of Sis1 with EEVD(Hsp70) minimizes transfer of Sis1-bound clients to Hsp70s that are primed for client transfer to folding and translocation pathways by their preassociation with EEVD binding adaptor proteins. These interactions may be one means by which cells triage Ydj1- and Sis1-bound clients to productive and quality control pathways, respectively. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. Molecular cloning of a Candida albicans gene (SSB1) coding for a protein related to the Hsp70 family.

    Science.gov (United States)

    Maneu, V; Cervera, A M; Martinez, J P; Gozalbo, D

    1997-06-15

    We have cloned and sequenced a Candida albicans gene (SSB1) encoding a potential member of the heat-shock protein seventy (hsp70) family. The protein encoded by this gene contains 613 amino acids and shows a high degree (85%) of sequence identity to the ssb subfamily (ssb1 and ssb2) of the Saccharomyces cerevisiae hsp70 family. The transcribed mRNA (2.1 kb) is present in similar amounts both in yeast and germ tube cells of C. albicans.

  19. Proteotoxicity is not the reason for the dependence of cancer cells on the major chaperone Hsp70.

    Science.gov (United States)

    Colvin, Teresa A; Gabai, Vladimir L; Sherman, Michael Y

    2014-01-01

    Several years ago a hypothesis was proposed that the survival of cancer cells depend on elevated expression of molecular chaperones because these cells are prone to proteotoxic stress. A critical prediction of this hypothesis is that depletion of chaperones in cancer cells should lead to proteotoxicity. Here, using the major chaperone Hsp70 as example, we demonstrate that its depletion does not trigger proteotoxic stress, thus refuting the model. Accordingly, other functions of chaperones, e.g., their role in cell signaling, might define the requirements for chaperones in cancer cells, which is critical for rational targeting Hsp70 in cancer treatment.

  20. Potential Response to Selection of HSP70 as a Component of Innate Immunity in the Abalone Haliotis rufescens

    Science.gov (United States)

    Brokordt, Katherina B.; González, Roxana C.; Farías, William J.; Winkler, Federico M.

    2015-01-01

    Assessing components of the immune system may reflect disease resistance. In some invertebrates, heat shock proteins (HSPs) are immune effectors and have been described as potent activators of the innate immune response. Several diseases have become a threat to abalone farming worldwide; therefore, increasing disease resistance is considered to be a long-term goal for breeding programs. A trait will respond to selection only if it is determined partially by additive genetic variation. The aim of this study was to estimate the heritability (h 2) and the additive genetic coefficient of variation (CV A) of HSP70 as a component of innate immunity of the abalone Haliotis rufescens, in order to assess its potential response to selection. These genetic components were estimated for the variations in the intracellular (in haemocytes) and extracellular (serum) protein levels of HSP70 in response to an immunostimulant agent in 60 full-sib families of H. rufescens. Levels of HSP70 were measured twice in the same individuals, first when they were young and again when they were pre-harvest adults, to estimate the repeatability (R), the h 2 and the potential response to selection of these traits at these life stages. High HSP70 levels were observed in abalones subjected to immunostimulation in both the intracellular and extracellular haemolymph fractions. This is the first time that changes in serum levels of HSP70 have been reported in response to an immune challenge in molluscs. HSP70 levels in both fractions and at both ages showed low h 2 and R, with values that were not significantly different from zero. However, HSP70 induced levels had a CV A of 13.3–16.2% in young adults and of 2.7–8.1% in pre-harvest adults. Thus, despite its low h 2, HSP70 synthesis in response to an immune challenge in red abalone has the potential to evolve through selection because of its large phenotypic variation and the presence of additive genetic variance, especially in young animals. PMID

  1. Potential Response to Selection of HSP70 as a Component of Innate Immunity in the Abalone Haliotis rufescens.

    Directory of Open Access Journals (Sweden)

    Katherina B Brokordt

    Full Text Available Assessing components of the immune system may reflect disease resistance. In some invertebrates, heat shock proteins (HSPs are immune effectors and have been described as potent activators of the innate immune response. Several diseases have become a threat to abalone farming worldwide; therefore, increasing disease resistance is considered to be a long-term goal for breeding programs. A trait will respond to selection only if it is determined partially by additive genetic variation. The aim of this study was to estimate the heritability (h2 and the additive genetic coefficient of variation (CVA of HSP70 as a component of innate immunity of the abalone Haliotis rufescens, in order to assess its potential response to selection. These genetic components were estimated for the variations in the intracellular (in haemocytes and extracellular (serum protein levels of HSP70 in response to an immunostimulant agent in 60 full-sib families of H. rufescens. Levels of HSP70 were measured twice in the same individuals, first when they were young and again when they were pre-harvest adults, to estimate the repeatability (R, the h2 and the potential response to selection of these traits at these life stages. High HSP70 levels were observed in abalones subjected to immunostimulation in both the intracellular and extracellular haemolymph fractions. This is the first time that changes in serum levels of HSP70 have been reported in response to an immune challenge in molluscs. HSP70 levels in both fractions and at both ages showed low h2 and R, with values that were not significantly different from zero. However, HSP70 induced levels had a CVA of 13.3-16.2% in young adults and of 2.7-8.1% in pre-harvest adults. Thus, despite its low h2, HSP70 synthesis in response to an immune challenge in red abalone has the potential to evolve through selection because of its large phenotypic variation and the presence of additive genetic variance, especially in young animals.

  2. Evolutionary Conservation and Emerging Functional Diversity of the Cytosolic Hsp70:J Protein Chaperone Network of Arabidopsis thaliana.

    Science.gov (United States)

    Verma, Amit K; Diwan, Danish; Raut, Sandeep; Dobriyal, Neha; Brown, Rebecca E; Gowda, Vinita; Hines, Justin K; Sahi, Chandan

    2017-06-07

    Heat shock proteins of 70 kDa (Hsp70s) partner with structurally diverse Hsp40s (J proteins), generating distinct chaperone networks in various cellular compartments that perform myriad housekeeping and stress-associated functions in all organisms. Plants, being sessile, need to constantly maintain their cellular proteostasis in response to external environmental cues. In these situations, the Hsp70:J protein machines may play an important role in fine-tuning cellular protein quality control. Although ubiquitous, the functional specificity and complexity of the plant Hsp70:J protein network has not been studied. Here, we analyzed the J protein network in the cytosol of Arabidopsis thaliana and, using yeast genetics, show that the functional specificities of most plant J proteins in fundamental chaperone functions are conserved across long evolutionary timescales. Detailed phylogenetic and functional analysis revealed that increased number, regulatory differences, and neofunctionalization in J proteins together contribute to the emerging functional diversity and complexity in the Hsp70:J protein network in higher plants. Based on the data presented, we propose that higher plants have orchestrated their "chaperome," especially their J protein complement, according to their specialized cellular and physiological stipulations. Copyright © 2017 Verma et al.

  3. Robust heat-inducible gene expression by two endogenous hsp70-derived promoters in transgenic Aedes aegypti

    Science.gov (United States)

    Carpenetti, Tiffany L. G.; Aryan, Azadeh; Myles, Kevin M.; Adelman, Zach N.

    2011-01-01

    Aedes aegypti is an important vector of the viruses that cause dengue fever, dengue hemorrhagic fever, and yellow fever. Reverse genetic approaches to the study of gene function in this mosquito have been limited by the lack of a robust inducible promoter to allow precise temporal control over a protein-encoding or hairpin RNA transgene. Likewise, investigations into the molecular and biochemical basis of vector competence would benefit from the ability to activate an anti-pathogen molecule at specific times during infection. We have characterized the ability of genomic sequences derived from two Ae. aegypti hsp70 genes to drive heat-inducible expression of a reporter in both transient and germline transformation contexts. AaHsp70-luciferase transcripts accumulated specifically after heat shock, and displayed a pattern of rapid induction and decay similar to endogenous AaHsp70 genes. Luciferase expression in transgenic Ae. aegypti increased by ∼25-50 fold in whole adults by four hours after heat-shock, with significant activity (∼20 fold) remaining at 24 hr. Heat-induced expression was even more dramatic in midgut tissues, with one strain showing a ∼2500-fold increase in luciferase activity. The AaHsp70 promoters described could be valuable for gene function studies as well as for the precise timing of the expression of anti-pathogen molecules. PMID:22142225

  4. Complex patterns of geographic variation in heat tolerance and Hsp70 expression levels in the common frog Rana temporaria

    DEFF Research Database (Denmark)

    Sørensen, Jesper Givskov; Pekkonen, Minna; Lindgren, Beatrice

    2009-01-01

    1. We tested for geographical variation in heat tolerance and Hsp70 expression levels of Rana temporaria tadpoles along a 1500 km long latitudinal gradient in Sweden.   2. Temperature tolerance of the hatchling tadpoles did not differ among populations, but they tolerated stressful hot temperatur...

  5. Modulation of ASK1 expression during overexpression of Trx and HSP70 in stressed fish liver mitochondria.

    Science.gov (United States)

    Padmini, Ekambaram; Vijaya Geetha, Bose

    2009-09-01

    Mitochondrial heat shock protein 70 (mtHSP70) is found to play a primary role in cellular defense against physiological stress like exposure to environmental contaminants and helpful in the maintenance of cellular homeostasis by promoting the cell survival. In the present investigation, the environmental-stress-induced increase in mtHSP70 levels along with the quantification of apoptosis signal regulating kinase 1 (ASK1) and thioredoxin (Trx) were measured in the liver mitochondria of grey mullets (Mugil cephalus) collected from the polluted Ennore estuary and the unpolluted Kovalam estuary for a period of 2 years. The results showed elevated lipid peroxide (LPO) and decreased total antioxidant capacity along with the decrease in mitochondrial viability percentage. Mitochondrial HSP70, ASK1, and Trx levels were increased under this stress condition. A 42% increase in LPO levels and 18% decrease in mitochondrial survivality were observed in the polluted-site fish liver mitochondria when compared to the results of unpolluted estuary. We also report that, under observed oxidative stress condition in Ennore fish samples, the ASK1 levels are only moderately elevated (13% increase). This may be due to mitochondrial-HSP70-induced adaptive tolerance signaling for the activation of Trx (22% increase) which suppresses the ASK1 expression thereby promoting the cell survival that leads to the maintenance of the cellular homeostasis.

  6. Phloroglucinol-Mediated Hsp70 Production in Crustaceans: Protection against Vibrio parahaemolyticus in Artemia franciscana and Macrobrachium rosenbergii

    Science.gov (United States)

    Kumar, Vikash; Baruah, Kartik; Nguyen, Dung Viet; Smagghe, Guy; Vossen, Els; Bossier, Peter

    2018-01-01

    The halophilic aquatic bacterium, Vibrio parahaemolyticus, is an important aquatic pathogen, also capable of causing acute hepatopancreatic necrosis disease (AHPND) in shrimp resulting in significant economic losses. Therefore, there is an urgent need to develop anti-infective strategies to control AHPND. The gnotobiotic Artemia model is used to establish whether a phenolic compound phloroglucinol is effective against the AHPND strain V. parahaemolyticus MO904. We found that pretreatment with phloroglucinol, at an optimum concentration (30 µM), protects axenic brine shrimp larvae against V. parahaemolyticus infection and induced heat shock protein 70 (Hsp70) production (twofolds or more) as compared with the control. We further demonstrated that the Vibrio-protective effect of phloroglucinol was caused by its prooxidant effect and is linked to the induction of Hsp70. In addition, RNA interference confirms that phloroglucinol-induced Hsp70 mediates the survival of brine shrimp larvae against V. parahaemolyticus infection. The study was validated in xenic Artemia model and in a Macrobrachium rosenbergii system. Pretreatment of xenic brine shrimp larvae (30 µM) and Macrobrachium larvae (5 µM) with phloroglucinol increases the survival of xenic brine shrimp and Macrobrachium larvae against subsequent V. parahaemolyticus challenge. Taken together, our study provides substantial evidence that the prooxidant activity of phloroglucinol induces Hsp70 production protecting brine shrimp, A. franciscana, and freshwater shrimp, M. rosenbergii, against the AHPND V. parahaemolyticus strain MO904. Probably, phloroglucinol treatment might become part of a holistic strategy to control AHPND in shrimp.

  7. ATPase Domain and Interdomain Linker Play a Key Role in Aggregation of Mitochondrial Hsp70 Chaperone Ssc1*

    Science.gov (United States)

    Blamowska, Marta; Sichting, Martin; Mapa, Koyeli; Mokranjac, Dejana; Neupert, Walter; Hell, Kai

    2010-01-01

    The co-chaperone Hep1 is required to prevent the aggregation of mitochondrial Hsp70 proteins. We have analyzed the interaction of Hep1 with mitochondrial Hsp70 (Ssc1) and the determinants in Ssc1 that make it prone to aggregation. The ATPase and peptide binding domain (PBD) of Hsp70 proteins are connected by a linker segment that mediates interdomain communication between the domains. We show here that the minimal Hep1 binding entity of Ssc1 consists of the ATPase domain and the interdomain linker. In the absence of Hep1, the ATPase domain with the interdomain linker had the tendency to aggregate, in contrast to the ATPase domain with the mutated linker segment or without linker, and in contrast to the PBD. The closest homolog of Ssc1, bacterial DnaK, and a Ssc1 chimera, in which a segment of the ATPase domain of Ssc1 was replaced by the corresponding segment from DnaK, did not aggregate in Δhep1 mitochondria. The propensity to aggregate appears to be a specific property of the mitochondrial Hsp70 proteins. The ATPase domain in combination with the interdomain linker is crucial for aggregation of Ssc1. In conclusion, our results suggest that interdomain communication makes Ssc1 prone to aggregation. Hep1 counteracts aggregation by binding to this aggregation-prone conformer. PMID:20007714

  8. ATPase domain and interdomain linker play a key role in aggregation of mitochondrial Hsp70 chaperone Ssc1.

    Science.gov (United States)

    Blamowska, Marta; Sichting, Martin; Mapa, Koyeli; Mokranjac, Dejana; Neupert, Walter; Hell, Kai

    2010-02-12

    The co-chaperone Hep1 is required to prevent the aggregation of mitochondrial Hsp70 proteins. We have analyzed the interaction of Hep1 with mitochondrial Hsp70 (Ssc1) and the determinants in Ssc1 that make it prone to aggregation. The ATPase and peptide binding domain (PBD) of Hsp70 proteins are connected by a linker segment that mediates interdomain communication between the domains. We show here that the minimal Hep1 binding entity of Ssc1 consists of the ATPase domain and the interdomain linker. In the absence of Hep1, the ATPase domain with the interdomain linker had the tendency to aggregate, in contrast to the ATPase domain with the mutated linker segment or without linker, and in contrast to the PBD. The closest homolog of Ssc1, bacterial DnaK, and a Ssc1 chimera, in which a segment of the ATPase domain of Ssc1 was replaced by the corresponding segment from DnaK, did not aggregate in Delta hep1 mitochondria. The propensity to aggregate appears to be a specific property of the mitochondrial Hsp70 proteins. The ATPase domain in combination with the interdomain linker is crucial for aggregation of Ssc1. In conclusion, our results suggest that interdomain communication makes Ssc1 prone to aggregation. Hep1 counteracts aggregation by binding to this aggregation-prone conformer.

  9. Involvement of p27CIP/KIP in HSP25 or HSP70 Mediated Adaptive Response by Low Dose Radiation

    International Nuclear Information System (INIS)

    Seo, Hang Rhan; Lee, Yoon Jin; Lee, Su Jae; Bae, Sang woo; Lee, Yun Sil

    2005-01-01

    Adaptive responses that reduce the harmful effects of subsequent exposure to high-dose radiation have demonstrated in chromosome aberration, cell survival, sister chromatid exchanges, micronucleus induction, mutation and neoplastic transformation. The mechanisms and conditions for the adaptive response to radiation have not been clarified, although the continuous production of free radicals from radiation and other sources has stimulated cells to evolve a repair system for chromosome breaks. An alteration of the DNA molecule triggers the repair system, and frequent activation may increase the general repair capacity, irrespective of the cause of the damage. Besides, cell cycle regulation systems, antioxidant defense systems, molecular chaperone or stress-response systems. Our previous data showed that when cells were preirradiated with 1cGy, they showed the adaptive response. A reduction of apoptosis by low-dose preirradiation is another potential mechanism for this effect. We previously demonstrated that mouse RIF cells, which did not induce HSP25 and HSP70 did not exhibit a adaptive response after 1cGy preirradiation. whereas the thermoresistant TR cells, which expressed inducible HSP25 and HSP70 showed a response. Moreover, when HSP70 and HSP25 were transfected to RIF cells, the cells acquired adaptive response. In this study, to elucidate the mechanisms in induction of adaptiveresponse, we compared cell cycle distribution by low dose radiation after HSP25 or HSP70 transfected cells and p27CIP/KIP is responsible for the different induction of adaptive response

  10. The small-molecule kinase inhibitor D11 counteracts 17-AAG-mediated up-regulation of HSP70 in brain cancer cells.

    Science.gov (United States)

    Schaefer, Susanne; Svenstrup, Tina H; Guerra, Barbara

    2017-01-01

    Many types of cancer express high levels of heat shock proteins (HSPs) that are molecular chaperones regulating protein folding and stability ensuring protection of cells from potentially lethal stress. HSPs in cancer cells promote survival, growth and spreading even in situations of growth factors deprivation by associating with oncogenic proteins responsible for cell transformation. Hence, it is not surprising that the identification of potent inhibitors of HSPs, notably HSP90, has been the primary research focus, in recent years. Exposure of cancer cells to HSP90 inhibitors, including 17-AAG, has been shown to cause resistance to chemotherapeutic treatment mostly attributable to induction of the heat shock response and increased cellular levels of pro-survival chaperones. In this study, we show that treatment of glioblastoma cells with 17-AAG leads to HSP90 inhibition indicated by loss of stability of the EGFR client protein, and significant increase in HSP70 expression. Conversely, co-treatment with the small-molecule kinase inhibitor D11 leads to suppression of the heat shock response and inhibition of HSF1 transcriptional activity. Beside HSP70, Western blot and differential mRNA expression analysis reveal that combination treatment causes strong down-regulation of the small chaperone protein HSP27. Finally, we demonstrate that incubation of cells with both agents leads to enhanced cytotoxicity and significantly high levels of LC3-II suggesting autophagy induction. Taken together, results reported here support the notion that including D11 in future treatment regimens based on HSP90 inhibition can potentially overcome acquired resistance induced by the heat shock response in brain cancer cells.

  11. Fluoro-edenite Fibers Induce Expression of Hsp70 and Inflammatory Response

    Directory of Open Access Journals (Sweden)

    Michael Balazy

    2007-09-01

    Full Text Available Many asbestos-like mineral fibers have been detected in the air of mountainous and volcanic areas of Italy and other parts of the world. These fibers have been suspected to be the cause of increased incidences of lung cancer and other lung diseases in these areas. However, the mechanisms of the cellular response and defense following exposure to these microscopic fibers have not been characterized. We continue to study these mechanisms to be able to propose preventive strategies in large populations. The objective of the present study was to determine comparatively biological responses of mesothelial Met-5A and monocyte-macrophage J774 cells following exposure to two types of fluoro-edenite fibers having low and high iron content (labeled 19 and 27, respectively obtained from Biancavilla (Sicily, Italy. The reference fiber was a non-iron fibrous tremolite from Val di Susa (Piemonte, Italy. The cells were treated with 5, 50, and 100 μg of fibrous matter per 1 ml for 72 hr. We identified several key mechanisms by which cells responded and counteracted the injury induced by these fibers. The fibers caused induction of the heat shock protein 70 (Hsp70, stimulated formation of reactive oxygen species (detected by using DCFH-DA as a fluorescent probe and NO• (measured as nitrite. Exposure of cells to the fibers induced lactate dehydrogenase activity and decreased viability. The fluoro-endenite type 27 was the most potent fiber tested, which indicated that iron and possibly manganese contribute significantly to this fiber toxicity. The J774 cells were more sensitive to fluoro-edenite than Met-5A cells suggesting that the primary site of the fiberinduced inflammatory response could be the macrophage rather than the pulmonary epithelium. Fluoro-edenite produces more biological alterations with respect to non-iron tremolite. Hsp70 and free radicals could be important factors in the context of mineral fiber-induced acute lung injury

  12. Insulated hsp70B' promoter: stringent heat-inducible activity in replication-deficient, but not replication-competent adenoviruses.

    Science.gov (United States)

    Rohmer, Stanimira; Mainka, Astrid; Knippertz, Ilka; Hesse, Andrea; Nettelbeck, Dirk M

    2008-04-01

    Key to the realization of gene therapy is the development of efficient and targeted gene transfer vectors. Therapeutic gene transfer by replication-deficient or more recently by conditionally replication-competent/oncolytic adenoviruses has shown much promise. For specific applications, however, it will be advantageous to provide vectors that allow for external control of gene expression. The efficient cellular heat shock system in combination with available technology for focused and controlled hyperthermia suggests heat-regulated transcription control as a promising tool for this purpose. We investigated the feasibility of a short fragment of the human hsp70B' promoter, with and without upstream insulator elements, for the regulation of transgene expression by replication-deficient or oncolytic adenoviruses. Two novel adenoviral vectors with an insulated hsp70B' promoter were developed and showed stringent heat-inducible gene expression with induction ratios up to 8000-fold. In contrast, regulation of gene expression from the hsp70B' promoter without insulation was suboptimal. In replication-competent/oncolytic adenoviruses regulation of the hsp70B' promoter was lost specifically during late replication in permissive cells and could not be restored by the insulators. We developed novel adenovirus gene transfer vectors that feature improved and stringent regulation of transgene expression from the hsp70B' promoter using promoter insulation. These vectors have potential for gene therapy applications that benefit from external modulation of therapeutic gene expression or for combination therapy with hyperthermia. Furthermore, our study reveals that vector replication can deregulate inserted cellular promoters, an observation which is of relevance for the development of replication-competent/oncolytic gene transfer vectors. (c) 2008 John Wiley & Sons, Ltd.

  13. Microbiota Composition, HSP70 and Caspase-3 Expression as Marker for Colorectal Cancer Patients in Aceh, Indonesia

    Directory of Open Access Journals (Sweden)

    Fauzi Yusuf

    2017-02-01

    Full Text Available Aim: to investigate the relationship between microbiota composition with HSP70 and Caspase-3 expressions in colon tissue as an initial study to develop the candidate for early detection of colorectal cancer for Indonesian patients. Methods: this is a cross-sectional study on 32 patients undergoing colonoscopy; 16 patients of colorectal cancer (CRC while the other 16 patients are not (colitis and internal hemorrhoid. The composition of microbiota in stool samples was examined using 16S rRNA Denaturing Gradient Gel Electrophoresis (DDGE while expression of HSP70 was examined by immunohistochemistry and Caspase-3 by using Haematoxylin-Eosin(HE staining to determine the morphological changes in colon tissue. Results: analysis of PCR-DDGE shows a different composition of microbiota between patients with CRC and non-CRC. All CRC patients showed disappearance of dominant band from Bifidobacterium groups. Histological observation based on Inter Class Correlation (ICC test from all slide showed a high scores (5.2-9.2 in CRC patients and low scores (1.7-2.4 in non-CRC patients. HSP70 expression was increased significantly in CRC patients with the highest percentage of 84%, while expression of caspase-3 decreased with the highest percentage of 21%. Statistical analysis showed that the incidence of colorectal cancer was associated with the expression of HSP 70 (p<0.001, and Caspase 3 (p<0.001. Conclusion: bifidobacterium is an important indicator for colorectal cancer patients that show disappearance of dominant band, while expression of HSP70 increased and the Caspase-3 expression decreased significantly.

  14. Human mitochondrial Hsp70 (mortalin): shedding light on ATPase activity, interaction with adenosine nucleotides, solution structure and domain organization.

    Science.gov (United States)

    Dores-Silva, Paulo R; Barbosa, Leandro R S; Ramos, Carlos H I; Borges, Júlio C

    2015-01-01

    The human mitochondrial Hsp70, also called mortalin, is of considerable importance for mitochondria biogenesis and the correct functioning of the cell machinery. In the mitochondrial matrix, mortalin acts in the importing and folding process of nucleus-encoded proteins. The in vivo deregulation of mortalin expression and/or function has been correlated with age-related diseases and certain cancers due to its interaction with the p53 protein. In spite of its critical biological roles, structural and functional studies on mortalin are limited by its insoluble recombinant production. This study provides the first report of the production of folded and soluble recombinant mortalin when co-expressed with the human Hsp70-escort protein 1, but it is still likely prone to self-association. The monomeric fraction of mortalin presented a slightly elongated shape and basal ATPase activity that is higher than that of its cytoplasmic counterpart Hsp70-1A, suggesting that it was obtained in the functional state. Through small angle X-ray scattering, we assessed the low-resolution structural model of monomeric mortalin that is characterized by an elongated shape. This model adequately accommodated high resolution structures of Hsp70 domains indicating its quality. We also observed that mortalin interacts with adenosine nucleotides with high affinity. Thermally induced unfolding experiments indicated that mortalin is formed by at least two domains and that the transition is sensitive to the presence of adenosine nucleotides and that this process is dependent on the presence of Mg2+ ions. Interestingly, the thermal-induced unfolding assays of mortalin suggested the presence of an aggregation/association event, which was not observed for human Hsp70-1A, and this finding may explain its natural tendency for in vivo aggregation. Our study may contribute to the structural understanding of mortalin as well as to contribute for its recombinant production for antitumor compound screenings.

  15. The function of the yeast molecular chaperone Sse1 is mechanistically distinct from the closely related hsp70 family.

    Science.gov (United States)

    Shaner, Lance; Trott, Amy; Goeckeler, Jennifer L; Brodsky, Jeffrey L; Morano, Kevin A

    2004-05-21

    The Sse1/Hsp110 molecular chaperones are a poorly understood subgroup of the Hsp70 chaperone family. Hsp70 can refold denatured polypeptides via a C-terminal peptide binding domain (PBD), which is regulated by nucleotide cycling in an N-terminal ATPase domain. However, unlike Hsp70, both Sse1 and mammalian Hsp110 bind unfolded peptide substrates but cannot refold them. To test the in vivo requirement for interdomain communication, SSE1 alleles carrying amino acid substitutions in the ATPase domain were assayed for their ability to complement sse1Delta yeast. Surprisingly, all mutants predicted to abolish ATP hydrolysis (D8N, K69Q, D174N, D203N) complemented the temperature sensitivity of sse1Delta and lethality of sse1Deltasse2Delta cells, whereas mutations in predicted ATP binding residues (G205D, G233D) were non-functional. Complementation ability correlated well with ATP binding assessed in vitro. The extreme C terminus of the Hsp70 family is required for substrate targeting and heterocomplex formation with other chaperones, but mutant Sse1 proteins with a truncation of up to 44 C-terminal residues that were not included in the PBD were active. Remarkably, the two domains of Sse1, when expressed in trans, functionally complement the sse1Delta growth phenotype and interact by coimmunoprecipitation analysis. In addition, a functional PBD was required to stabilize the Sse1 ATPase domain, and stabilization also occurred in trans. These data represent the first structure-function analysis of this abundant but ill defined chaperone, and establish several novel aspects of Sse1/Hsp110 function relative to Hsp70.

  16. Adaptive capability as indicated by behavioral and physiological responses, plasma HSP70 level, and PBMC HSP70 mRNA expression in Osmanabadi goats subjected to combined (heat and nutritional) stressors

    Science.gov (United States)

    Shilja, Shaji; Sejian, V.; Bagath, M.; Mech, A.; David, C. G.; Kurien, E. K.; Varma, Girish; Bhatta, Raghavendra

    2016-09-01

    A study was conducted to assess the impact of heat and nutritional stress simultaneously on the adaptive capability as indicated by behavioral and physiological responses, plasma heat shock protein 70 (HSP70) level, and peripheral blood mononuclear cells (PBMC) HSP70 gene expression in goats. Twenty-four adult Osmanabadi bucks (average body weight (BW) 16.0 kg) were used in the present study. The bucks were divided into four groups viz., C ( n = 6; control), HS ( n = 6; heat stress), NS ( n = 6; nutritional stress), and CS ( n = 6; combined stress). The study was conducted for a period of 45 days. C and HS bucks had ad libitum access to their feed while NS and CS bucks were under restricted feed (30 % intake of C bucks) to induce nutritional stress. The HS and CS bucks were exposed to solar radiation for 6 h a day between 10:00 a.m. and 4:00 p.m. to induce heat stress. The data was analyzed using repeated measures analysis of variance. The standing time differed significantly ( P < 0.01) between ad libitum fed groups (C and HS) and restricted feeding groups (NS and CS). The highest ( P < 0.01) lying time was recorded in the CS group while the lowest in the C and HS groups. The highest ( P < 0.01) drinking frequency was also recorded in the CS group. Water intake recorded was significantly ( P < 0.01) higher in both the HS and CS groups. The highest respiration rate (RR), pulse rate (PR), and rectal temperature (RT) during the afternoon were also recorded in the CS group. Further, skin temperature of the head, flank, and scrotum during the afternoon was also higher ( P < 0.01) in the CS group. In addition, both plasma HSP70 concentration and PBMC HSP70 messenger RNA (mRNA) transcript expression were also significantly ( P < 0.01) higher in the CS group. It can be concluded from this study that when two stressors occur simultaneously, they may have severe impact on adaptive capabilities of Osmanabadi bucks as compared to that would occur individually. Further, the

  17. Optimization of expression and purification of human mortalin (Hsp70): Folding/unfolding analysis

    Science.gov (United States)

    Khan, Mohd Shahnawaz; Ahmed, Anwar; Tabrez, Shams; Islam, Badar ul; Rabbani, Nayyar; Malik, Ajamaluddin; Ismael, Mohamad A.; Alsenaidy, Mohammad A.; Alsenaidy, Abdulrahman M.

    2017-12-01

    Human mortalin is a Hsp70 mitochondrial protein that plays an essential role in the biogenesis of mitochondria. The deregulation of mortalin expression and its functions could lead to several age-associated disorders and some types of cancers. In the present study, we optimized the expression and purification of recombinant human mortalin by the use of two-step chromatography. Low temperature (18 °C) and 0.5 mM (IPTG) was required for optimum mortalin expression. Chaperone activity of mortalin was assessed by the citrate synthase and insulin protection assay, which suggested their protective role in mitochondria. Folding and unfolding assessments of mortalin were carried out in the presence of guanidine hydrochloride (GdnHCl) by intrinsic fluorescence measurement, ANS (8-analino 1-nephthlene sulfonic acid) binding and CD (circular dichroism) analysis. Under denaturing conditions, mortalin showed decrease in tryptophan fluorescence intensity along with a red shift of 11 nm. Moreover, ANS binding studies illustrated decrease in hydrophobicity. CD measurement of mortalin showed a predominant helical structure. However, the secondary structure was lost at low concentration of GdnHCl (1 M). We present a simple and robust method to produce soluble mortalin and warranted that chaperones are also susceptible to unfolding and futile to maintain protein homeostasis.

  18. A Novel Protein Interaction between Nucleotide Binding Domain of Hsp70 and p53 Motif

    Directory of Open Access Journals (Sweden)

    Asita Elengoe

    2015-01-01

    Full Text Available Currently, protein interaction of Homo sapiens nucleotide binding domain (NBD of heat shock 70 kDa protein (PDB: 1HJO with p53 motif remains to be elucidated. The NBD-p53 motif complex enhances the p53 stabilization, thereby increasing the tumor suppression activity in cancer treatment. Therefore, we identified the interaction between NBD and p53 using STRING version 9.1 program. Then, we modeled the three-dimensional structure of p53 motif through homology modeling and determined the binding affinity and stability of NBD-p53 motif complex structure via molecular docking and dynamics (MD simulation. Human DNA binding domain of p53 motif (SCMGGMNR retrieved from UniProt (UniProtKB: P04637 was docked with the NBD protein, using the Autodock version 4.2 program. The binding energy and intermolecular energy for the NBD-p53 motif complex were −0.44 Kcal/mol and −9.90 Kcal/mol, respectively. Moreover, RMSD, RMSF, hydrogen bonds, salt bridge, and secondary structure analyses revealed that the NBD protein had a strong bond with p53 motif and the protein-ligand complex was stable. Thus, the current data would be highly encouraging for designing Hsp70 structure based drug in cancer therapy.

  19. Hsp10, Hsp70, and Hsp90 immunohistochemical levels change in ulcerative colitis after therapy

    Directory of Open Access Journals (Sweden)

    G. Tomasello

    2011-10-01

    Full Text Available Ulcerative colitis (UC is a form of inflammatory bowel disease (IBD characterized by damage of large bowel mucosa and frequent extra-intestinal autoimmune comorbidities. The role played in IBD pathogenesis by molecular chaperones known to interact with components of the immune system involved in inflammation is unclear. We previously demonstrated that mucosal Hsp60 decreases in UC patients treated with conventional therapies (mesalazine, probiotics, suggesting that this chaperonin could be a reliable biomarker useful for monitoring response to treatment, and that it might play a role in pathogenesis. In the present work we investigated three other heat shock protein/molecular chaperones: Hsp10, Hsp70, and Hsp90. We found that the levels of these proteins are increased in UC patients at the time of diagnosis and decrease after therapy, supporting the notion that these proteins deserve attention in the study of the mechanisms that promote the development and maintenance of IBD, and as biomarkers of this disease (e.g., to monitor response to treatment at the histological level.

  20. Comparative baseline levels of mercury, Hsp 70 and Hsp 60 in subsistence fish from the Yukon-Kuskokwim delta region of Alaska.

    Science.gov (United States)

    Duffy, L K; Scofield, E; Rodgers, T; Patton, M; Bowyer, R T

    1999-10-01

    In subsistence fish; northern pike (Esox lucius), burbot (Lota lota), whitefish (Coregonus nelsoni), grayling (Thymallus arcticus) and sheefish (Stenodus lencichthys), we determined the Hsp 60 and Hsp 70 levels in 31 samples from adult fish gills. A dot-blot analysis using antibodies to either Hsp 70 or Hsp 60 showed the average Hsp 70 concentration was 9.1 microg/mg protein, while the average Hsp 60 concentration was 147.4 microg/mg protein. Mercury levels in muscle tissue in these fish averaged 0.382 ppm. Using a subset of samples (n = 24), we determined that the major component in the muscle of Alaskan subsistence fish was methyl mercury. No correlation was observed between Hsp 60 or Hsp 70 expression in gill tissue and mercury concentrations in muscle tissue. Hsp 60 and Hsp 70 protein levels in the gills were correlated.

  1. Identification of the divergent calmodulin binding motif in yeast Ssb1/Hsp75 protein and in other HSP70 family members.

    Science.gov (United States)

    Heinen, R C; Diniz-Mendes, L; Silva, J T; Paschoalin, V M F

    2006-11-01

    Yeast soluble proteins were fractionated by calmodulin-agarose affinity chromatography and the Ca2+/calmodulin-binding proteins were analyzed by SDS-PAGE. One prominent protein of 66 kDa was excised from the gel, digested with trypsin and the masses of the resultant fragments were determined by MALDI/MS. Twenty-one of 38 monoisotopic peptide masses obtained after tryptic digestion were matched to the heat shock protein Ssb1/Hsp75, covering 37% of its sequence. Computational analysis of the primary structure of Ssb1/Hsp75 identified a unique potential amphipathic alpha-helix in its N-terminal ATPase domain with features of target regions for Ca2+/calmodulin binding. This region, which shares 89% similarity to the experimentally determined calmodulin-binding domain from mouse, Hsc70, is conserved in near half of the 113 members of the HSP70 family investigated, from yeast to plant and animals. Based on the sequence of this region, phylogenetic analysis grouped the HSP70s in three distinct branches. Two of them comprise the non-calmodulin binding Hsp70s BIP/GR78, a subfamily of eukaryotic HSP70 localized in the endoplasmic reticulum, and DnaK, a subfamily of prokaryotic HSP70. A third heterogeneous group is formed by eukaryotic cytosolic HSP70s containing the new calmodulin-binding motif and other cytosolic HSP70s whose sequences do not conform to those conserved motif, indicating that not all eukaryotic cytosolic Hsp70s are target for calmodulin regulation. Furthermore, the calmodulin-binding domain found in eukaryotic HSP70s is also the target for binding of Bag-1 - an enhancer of ADP/ATP exchange activity of Hsp70s. A model in which calmodulin displaces Bag-1 and modulates Ssb1/Hsp75 chaperone activity is discussed.

  2. Identification of the divergent calmodulin binding motif in yeast Ssb1/Hsp75 protein and in other HSP70 family members

    Directory of Open Access Journals (Sweden)

    R.C. Heinen

    2006-11-01

    Full Text Available Yeast soluble proteins were fractionated by calmodulin-agarose affinity chromatography and the Ca2+/calmodulin-binding proteins were analyzed by SDS-PAGE. One prominent protein of 66 kDa was excised from the gel, digested with trypsin and the masses of the resultant fragments were determined by MALDI/MS. Twenty-one of 38 monoisotopic peptide masses obtained after tryptic digestion were matched to the heat shock protein Ssb1/Hsp75, covering 37% of its sequence. Computational analysis of the primary structure of Ssb1/Hsp75 identified a unique potential amphipathic alpha-helix in its N-terminal ATPase domain with features of target regions for Ca2+/calmodulin binding. This region, which shares 89% similarity to the experimentally determined calmodulin-binding domain from mouse, Hsc70, is conserved in near half of the 113 members of the HSP70 family investigated, from yeast to plant and animals. Based on the sequence of this region, phylogenetic analysis grouped the HSP70s in three distinct branches. Two of them comprise the non-calmodulin binding Hsp70s BIP/GR78, a subfamily of eukaryotic HSP70 localized in the endoplasmic reticulum, and DnaK, a subfamily of prokaryotic HSP70. A third heterogeneous group is formed by eukaryotic cytosolic HSP70s containing the new calmodulin-binding motif and other cytosolic HSP70s whose sequences do not conform to those conserved motif, indicating that not all eukaryotic cytosolic Hsp70s are target for calmodulin regulation. Furthermore, the calmodulin-binding domain found in eukaryotic HSP70s is also the target for binding of Bag-1 - an enhancer of ADP/ATP exchange activity of Hsp70s. A model in which calmodulin displaces Bag-1 and modulates Ssb1/Hsp75 chaperone activity is discussed.

  3. 4-Phenylbutyrate stimulates Hsp70 expression through the Elp2 component of elongator and STAT-3 in cystic fibrosis epithelial cells.

    Science.gov (United States)

    Suaud, Laurence; Miller, Katelyn; Panichelli, Ashley E; Randell, Rachel L; Marando, Catherine M; Rubenstein, Ronald C

    2011-12-30

    Sodium 4-phenylbutyrate (4PBA) corrects trafficking of ΔF508-CFTR in Cystic Fibrosis (CF) epithelia, which is hypothesized to, at least in part, result from increased expression of Hsp70 (stress-induced 70 kDa heat shock protein). To identify other 4PBA-regulated proteins that may promote correction of ΔF508 trafficking, we performed differential display RT-PCR on mRNA from IB3-1 CF bronchiolar epithelial cells treated for 0-24 h with 1 mM 4PBA. In this screen, a STAT-3 (signal transducer and activator of transcription-3)-interacting protein, StIP-1 that regulates STAT-3 activation had transiently increased expression. StIP-1 is identical to Elongator protein 2 (Elp2), a component of the Elongator complex that regulates RNA polymerase II. Previous studies have suggested that Elongator regulates Hsp70 mRNA transcription, and that the Hsp70 promoter contains functional STAT-3-binding sites. We therefore tested the hypothesis that 4PBA increases Hsp70 expression by an Elongator- and STAT-3-dependent mechanism. 4PBA treatment of IB3-1 CF bronchiolar epithelial cells caused transiently increased expression of Hsp70 protein, as well as Elp2 protein and mRNA. Elp2 depletion by transfection of small interfering RNAs, reduced both Elp2 and Hsp70 protein expression. 4PBA also caused transient activation of STAT-3, and increased abundance of nuclear proteins that bind to the STAT-3-responsive element of the Hsp70 promoter. Luciferase reporter assays demonstrated that both Elp2 overexpression and 4PBA increase Hsp70 promoter activity, while Elp2 depletion blocked the ability of 4PBA to stimulate Hsp70 promoter activity. Together, these data suggest that Elp2 and STAT-3 mediate, at least in part, the stimulation of Hsp70 expression by 4PBA.

  4. Metallothionein and Hsp70 trade-off against one another in Daphnia magna cross-tolerance to cadmium and heat stress

    Energy Technology Data Exchange (ETDEWEB)

    Haap, Timo, E-mail: timo.haap@gmx.de; Schwarz, Simon; Köhler, Heinz-R.

    2016-01-15

    Highlights: • Cadmium acclimation of two Daphnia magna clones which differed in Cd sensitivity and Hsp70 levels. • Two distinct metal-handling strategies regarding Hsp70 and MT expression were observed. • High Hsp70 levels did not confer an increase in Cd and heat stress tolerance. • Our results indicate a trade-off between Hsp70 and MT. - Abstract: The association between the insensitivity of adapted ecotypes of invertebrates to environmental stress, such as heavy metal pollution, and overall low Hsp levels characterizing these organisms has been attracting attention in various studies. The present study seeks to induce and examine this phenomenon in Daphnia magna by multigenerational acclimation to cadmium in a controlled laboratory setting. In this experiment, interclonal variation was examined: two clones of D. magna that have previously been characterized to diverge regarding their cadmium resistance and levels of the stress protein Hsp70, were continuously exposed to a sublethal concentration of Cd over four generations to study the effects of acclimation on Hsp70, metallothionein (MT), reproduction and cross-tolerance to heat stress. The two clones differed in all the measured parameters in a characteristic way, clone T displaying Cd and heat resistance, lower Hsp70 levels and offspring numbers on the one hand and higher MT expression on the other hand, clone S the opposite for all these parameters. We observed only slight acclimation-induced changes in constitutive Hsp70 levels and reproductive output. The differences in MT expression between clones as well as between acclimated organisms and controls give evidence for MT accounting for the higher Cd tolerance of clone T. Overall high Hsp70 levels of clone S did not confer cross tolerance to heat stress, contrary to common expectations. Our results suggest a trade-off between the efforts to limit the proteotoxic symptoms of Cd toxicity by Hsp70 induction and those to sequester and detoxify Cd by

  5. Fasting enhances TRAIL-mediated liver natural killer cell activity via HSP70 upregulation.

    Directory of Open Access Journals (Sweden)

    Vu T A Dang

    Full Text Available Acute starvation, which is frequently observed in clinical practice, sometimes augments the cytolytic activity of natural killer cells against neoplastic cells. In this study, we investigated the molecular mechanisms underlying the enhancement of natural killer cell function by fasting in mice. The total number of liver resident natural killer cells in a unit weight of liver tissue obtained from C57BL/6J mice did not change after a 3-day fast, while the proportions of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL+ and CD69+ natural killer cells were significantly elevated (n = 7, p <0.01, as determined by flow cytometric analysis. Furthermore, we found that TRAIL- natural killer cells that were adoptively transferred into Rag-2-/- γ chain-/- mice could convert into TRAIL+ natural killer cells in fasted mice at a higher proportion than in fed mice. Liver natural killer cells also showed high TRAIL-mediated antitumor function in response to 3-day fasting. Since these fasted mice highly expressed heat shock protein 70 (n = 7, p <0.05 in liver tissues, as determined by western blot, the role of this protein in natural killer cell activation was investigated. Treatment of liver lymphocytes with 50 µg/mL of recombinant heat shock protein 70 led to the upregulation of both TRAIL and CD69 in liver natural killer cells (n = 6, p <0.05. In addition, HSP70 neutralization by intraperitoneally injecting an anti- heat shock protein 70 monoclonal antibody into mice prior to fasting led to the downregulation of TRAIL expression (n = 6, p <0.05. These findings indicate that acute fasting enhances TRAIL-mediated liver natural killer cell activity against neoplastic cells through upregulation of heat shock protein 70.

  6. Production and immune response of recombinant Hsp60 and Hsp70 from the salmon pathogen Piscirickettsia salmonis

    Directory of Open Access Journals (Sweden)

    VIVIAN WILHELM

    2005-01-01

    Full Text Available We have isolated and sequenced the genes encoding the heat shock proteins 60 (Hsp60 and 70 (Hsp70 of the salmon pathogen Piscirickettsia salmonis. The sequence analysis revealed the expected two open reading frames that encode proteins with calculated molecular weights of 60,060 and 70,400. The proteins exhibit a 70-80% homology with other known prokaryotic Hsp60 and Hsp70 sequences. The coding regions have been expressed in E. coli as thioredoxin fusion proteins. Both recombinant proteins were shown to elicit a humoral response when injected intraperitoneally in Atlantic salmon and also conferred protection to fish challenged with P. salmonis. The present data will facilitate further studies on the involvement of heat shock proteins in protective immunity of fish to infection by P. salmonis and their potential use in recombinants vaccines against this intracellular pathogen.

  7. A fraction from Petiveria alliacea induces apoptosis via a mitochondria-dependent pathway and regulates HSP70 expression

    Directory of Open Access Journals (Sweden)

    Susana Fiorentino

    2009-12-01

    Full Text Available To evaluate the biological activity of Petiveria alliacea extracts on tumoral cells in vitro. Materials and methods. P.alliaceafractions prepared by a bioguided purification protocol were characterized by their biological activities on two human tumoral cell lines.Morphological changes, cell viability, mitochondrial membrane depolarization, nuclear staining and activity on HSP70 were analyzed.Results. The present study demonstrates that P.alliacea fractions can induce apoptosis in a mitochondria-dependent pathway and downregulate HSP70 expression in vitro. The possible compounds present in P.alliacea responsible for the described biological activities wereidentified by dereplication methods. Conclusion. The present study provides new knowledge on the antitumoral properties of the plantspecies P. alliacea described in several ethnobotanical studies.

  8. Nanomechanics of the substrate binding domain of Hsp70 determine its allosteric ATP-induced conformational change.

    Science.gov (United States)

    Mandal, Soumit Sankar; Merz, Dale R; Buchsteiner, Maximilian; Dima, Ruxandra I; Rief, Matthias; Žoldák, Gabriel

    2017-06-06

    Owing to the cooperativity of protein structures, it is often almost impossible to identify independent subunits, flexible regions, or hinges simply by visual inspection of static snapshots. Here, we use single-molecule force experiments and simulations to apply tension across the substrate binding domain (SBD) of heat shock protein 70 (Hsp70) to pinpoint mechanical units and flexible hinges. The SBD consists of two nanomechanical units matching 3D structural parts, called the α- and β-subdomain. We identified a flexible region within the rigid β-subdomain that gives way under load, thus opening up the α/β interface. In exactly this region, structural changes occur in the ATP-induced opening of Hsp70 to allow substrate exchange. Our results show that the SBD's ability to undergo large conformational changes is already encoded by passive mechanics of the individual elements.

  9. Reduced heat shock response in human mononuclear cells during aging and its association with polymorphisms in HSP70 genes

    DEFF Research Database (Denmark)

    Singh, Ripudaman; Kølvraa, Steen; Bross, Peter

    2006-01-01

    Age-dependent changes in heat shock response (HSR) were studied in mononuclear cells (monocytes and lymphocytes) collected from young (mean age = 22.6 +/- 1.7 years) and middle-aged (mean age = 56.3 +/- 4.7 years) subjects after 1 hour of heat shock at 42 degrees C. Genotype-specific HSR...... was measured by genotyping the subjects for 3 single nucleotide polymorphisms, HSPA1A(A-110C), HSPA1B(A1267G), and HSPA1L(T2437C), 1 each in the 3 HSP70 genes. A significant age-related decrease in the induction of Hsp70 occurred after heat shock in both monocytes and lymphocytes. The noninducible...

  10. In situ mapping of the hsp70 locus in seven species of the willistoni group of Drosophila

    International Nuclear Information System (INIS)

    Bonorino, C.B.C.; Valente, V.L.S.; Pereira, M.; Alonso, C.E.V.; Abdelhay, E.

    1993-01-01

    The hsp70 locus was mapped by in situ hybridization of a biotinylated probe (p PW 229) to the polythene chromosomes of seven species of the willistoni group of Drosophila. In all of them, the probe hybridized mainly at a single site of the third chromosome, corresponding in each case to a heat-induced puff site. Southern blot analysis comparing the Eco RI digested DNA of the willistoni species with D. melanogaster revealed that a large segment of DNA homologous to the hsp 70 probe detected in D. melanogaster does not exist in the willistoni group. These results suggested that this locus is not duplicated in the willistoni group as it is in the melanogaster. (author)

  11. Phloroglucinol-Mediated Hsp70 Production in Crustaceans: Protection against Vibrio parahaemolyticus in Artemia franciscana and Macrobrachium rosenbergii

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    Vikash Kumar

    2018-05-01

    Full Text Available The halophilic aquatic bacterium, Vibrio parahaemolyticus, is an important aquatic pathogen, also capable of causing acute hepatopancreatic necrosis disease (AHPND in shrimp resulting in significant economic losses. Therefore, there is an urgent need to develop anti-infective strategies to control AHPND. The gnotobiotic Artemia model is used to establish whether a phenolic compound phloroglucinol is effective against the AHPND strain V. parahaemolyticus MO904. We found that pretreatment with phloroglucinol, at an optimum concentration (30 µM, protects axenic brine shrimp larvae against V. parahaemolyticus infection and induced heat shock protein 70 (Hsp70 production (twofolds or more as compared with the control. We further demonstrated that the Vibrio-protective effect of phloroglucinol was caused by its prooxidant effect and is linked to the induction of Hsp70. In addition, RNA interference confirms that phloroglucinol-induced Hsp70 mediates the survival of brine shrimp larvae against V. parahaemolyticus infection. The study was validated in xenic Artemia model and in a Macrobrachium rosenbergii system. Pretreatment of xenic brine shrimp larvae (30 µM and Macrobrachium larvae (5 µM with phloroglucinol increases the survival of xenic brine shrimp and Macrobrachium larvae against subsequent V. parahaemolyticus challenge. Taken together, our study provides substantial evidence that the prooxidant activity of phloroglucinol induces Hsp70 production protecting brine shrimp, A. franciscana, and freshwater shrimp, M. rosenbergii, against the AHPND V. parahaemolyticus strain MO904. Probably, phloroglucinol treatment might become part of a holistic strategy to control AHPND in shrimp.

  12. Examination the expression pattern of HSP70 heat shock protein in chicken PGCs and developing genital ridge

    OpenAIRE

    Mahek Anand; Roland Tóth; Alayu Kidane; Alexandra Nagy; Bence Lázár; Eszter Patakiné Várkonyi; Krisztina Liptói; Elen Gocza

    2016-01-01

    Chicken Primordial Germ cells (PGCs) are emerging pioneers in the field of applied embryology and stem cell technology. Now-a-days transgenic chickens are promising models to study human disease pathophysiology and drug designing. However, most of the molecular mechanism, which govern the stemness and pluripotency of chicken PGCs, not known in details. Recent studies have indicated the role of HSP70 in early embryonic development in many vertebrate species. Exposure of chicken to heat...

  13. A fraction from Petiveria alliacea induces apoptosis via a mitochondria-dependent pathway and regulates HSP70 expression

    OpenAIRE

    Susana Fiorentino; Diana Mercedes Castañeda; Claudia Patricia Urueña; Maria Claudia Cifuentes

    2009-01-01

    To evaluate the biological activity of Petiveria alliacea extracts on tumoral cells in vitro. Materials and methods. P.alliaceafractions prepared by a bioguided purification protocol were characterized by their biological activities on two human tumoral cell lines.Morphological changes, cell viability, mitochondrial membrane depolarization, nuclear staining and activity on HSP70 were analyzed.Results. The present study demonstrates that P.alliacea fractions can induce apoptosis in a mitochond...

  14. Phenotypic Plasticity of HSP70s Gene Expression during Diapause: Signs of Evolutionary Responses to Cold Stress among Soybean Pod Borer Populations (Leguminivora glycinivorella) in Northeast of China

    Science.gov (United States)

    Han, Lanlan; Fan, Dong; Zhao, Kuijun

    2014-01-01

    The soybean pod borer (Leguminivora glycinivorella Matsumura) successfully survives the winter because of its high expression of 70-kDa heat shock proteins (HSP70s) during its overwintering diapause. The amount of HSP70s is different under different environmental stresses. In this study, inducible heat shock protein 70 and its constitutive heat shock cognate 70 were cloned by RT-PCR and RACE. These genes were named Lg-hsp70 and Lg-hsc70, respectively. Gene transcription and protein expression after cold stress treatment (5°C to −5°C) were analyzed by western blotting and by qRT-PCR for four populations that were sampled in the northeast region of China, including Shenyang, Gongzhuling, Harbin and Heihe, when the soybean pod borer was in diapause. As the cold shock temperature decreased, the levels of Lg-HSP70s were significantly up-regulated. The amount of cold-induced Lg-HSP70s was highest in the southernmost population (Shenyang, 41°50′N) and lowest in the northernmost population (Heihe, 50°22′N). These results support the hypothesis that the soybean pod borer in the northeast region of China displays phenotypic plasticity, and the accumulation of Lg-HSP70s is a strategy for overcoming environmental stress. These results also suggest that the induction of HSP70 synthesis, which is a complex physiological adaptation, can evolve quickly and inherit stability. PMID:25330365

  15. Identification of cytosolic peroxisome proliferator binding protein as a member of the heat shock protein HSP70 family.

    Science.gov (United States)

    Alvares, K; Carrillo, A; Yuan, P M; Kawano, H; Morimoto, R I; Reddy, J K

    1990-01-01

    Clofibrate and many of its structural analogues induce proliferation of peroxisomes in the hepatic parenchymal cells of rodents and certain nonrodent species including primates. This induction is tissue specific, occurring mainly in the liver parenchymal cells and to a lesser extent in the kidney cortical epithelium. The induction of peroxisomes is associated with a predictable pleiotropic response, characterized by hepatomegaly, and increased activities and mRNA levels of certain peroxisomal enzymes. Using affinity chromatography, we had previously isolated a protein that binds to clofibric acid. We now show that this protein is homologous with the heat shock protein HSP70 family by analysis of amino acid sequences of isolated peptides from trypsin-treated clofibric acid binding protein and by cross-reactivity with a monoclonal antibody raised against the conserved region of the 70-kDa heat shock proteins. The clofibric acid-Sepharose column could bind HSP70 proteins isolated from various species, which could then be eluted with either clofibric acid or ATP. Conversely, when a rat liver cytosol containing multiple members of the HSP70 family was passed through an ATP-agarose column, and eluted with clofibric acid, only P72 (HSC70) was eluted. These results suggest that clofibric acid, a peroxisome proliferator, preferentially interacts with P72 at or near the ATP binding site. Images PMID:2371272

  16. Differentiation of Leishmania (Viannia) panamensis and Leishmania (V.) guyanensis using BccI for hsp70 PCR-RFLP.

    Science.gov (United States)

    Montalvo Alvarez, Ana Margarita; Nodarse, Jorge Fraga; Goodridge, Ivón Montano; Fidalgo, Lianet Monzote; Marin, Marcel; Van Der Auwera, Gert; Dujardin, Jean-Claude; Bernal, Iván Darío Velez; Muskus, Carlos

    2010-05-01

    Leishmania panamensis and Leishmania guyanensis are two species of the subgenus Viannia that are genetically very similar. Both parasites are usually associated with cutaneous leishmaniasis, but also have the potential to cause the mucocutaneous form of the disease. In addition, the study of foci and consequently the identification of vectors and probable reservoirs involved in transmission require a correct differentiation between both species, which is important at epidemiological level. We explored the possibility of identifying these species by using restriction fragment length polymorphisms (RFLP) in the gene coding for heat-shock protein 70 (hsp70). Previously, an hsp70 PCR-RFLP assay proved to be very effective in differentiating other Leishmania species when HaeIII is used as restriction enzyme. Based on hsp70 sequences analysis, BccI was found to generate species-specific fragments that can easily be recognized by agarose gel electrophoresis. Using the analysis of biopsies, scrapings, and parasite isolates previously grouped in a cluster comprising both L. panamensis and L. guyanensis, we showed that our approach allowed differentiation of both entities. This offers the possibility not only for identification of parasites in biological samples, but also to apply molecular epidemiology in certain countries of the New World, where several Leishmania species could coexist. Copyright 2009 Royal Society of Tropical Medicine and Hygiene. Published by Elsevier Ltd. All rights reserved.

  17. Schiff Base Metal Derivatives Enhance the Expression of HSP70 and Suppress BAX Proteins in Prevention of Acute Gastric Lesion

    Directory of Open Access Journals (Sweden)

    Shahram Golbabapour

    2013-01-01

    Full Text Available Schiff base complexes have appeared to be promising in the treatment of different diseases and disorders and have drawn a lot of attention to their biological activities. This study was conducted to evaluate the regulatory effect of Schiff base metal derivatives on the expression of heat shock proteins (HSP 70 and BAX in protection against acute haemorrhagic gastric ulcer in rats. Rats were assigned to 6 groups of 6 rats: the normal control (Tween 20 5% v/v, 5 mL/kg, the positive control (Tween 20 5% v/v, 5 mL/kg, and four Schiff base derivative groups named Schiff_1, Schiff_2, Schiff_3, and Schiff_4 (25 mg/kg. After 1 h, all of the groups received ethanol 95% (5 mL/kg but the normal control received Tween 20 (Tween 20 5% v/v, 5 mL/kg. The animals were euthanized after 60 min and the stomachs were dissected for histology (H&E, immunohistochemistry, and western blot analysis against HSP70 and BAX proteins. The results showed that the Schiff base metal derivatives enhanced the expression of HSP70 and suppressed the expression of BAX proteins during their gastroprotection against ethanol-induced gastric lesion in rats.

  18. Schiff base metal derivatives enhance the expression of HSP70 and suppress BAX proteins in prevention of acute gastric lesion.

    Science.gov (United States)

    Golbabapour, Shahram; Gwaram, Nura Suleiman; Al-Obaidi, Mazen M Jamil; Soleimani, A F; Ali, Hapipah Mohd; Abdul Majid, Nazia

    2013-01-01

    Schiff base complexes have appeared to be promising in the treatment of different diseases and disorders and have drawn a lot of attention to their biological activities. This study was conducted to evaluate the regulatory effect of Schiff base metal derivatives on the expression of heat shock proteins (HSP) 70 and BAX in protection against acute haemorrhagic gastric ulcer in rats. Rats were assigned to 6 groups of 6 rats: the normal control (Tween 20 5% v/v, 5 mL/kg), the positive control (Tween 20 5% v/v, 5 mL/kg), and four Schiff base derivative groups named Schiff_1, Schiff_2, Schiff_3, and Schiff_4 (25 mg/kg). After 1 h, all of the groups received ethanol 95% (5 mL/kg) but the normal control received Tween 20 (Tween 20 5% v/v, 5 mL/kg). The animals were euthanized after 60 min and the stomachs were dissected for histology (H&E), immunohistochemistry, and western blot analysis against HSP70 and BAX proteins. The results showed that the Schiff base metal derivatives enhanced the expression of HSP70 and suppressed the expression of BAX proteins during their gastroprotection against ethanol-induced gastric lesion in rats.

  19. First cellular approach of the effects of global warming on groundwater organisms: a study of the HSP70 gene expression.

    Science.gov (United States)

    Colson-Proch, Céline; Morales, Anne; Hervant, Frédéric; Konecny, Lara; Moulin, Colette; Douady, Christophe J

    2010-05-01

    Whereas the consequences of global warming at population or community levels are well documented, studies at the cellular level are still scarce. The study of the physiological or metabolic effects of such small increases in temperature (between +2 degrees C and +6 degrees C) is difficult because they are below the amplitude of the daily or seasonal thermal variations occurring in most environments. In contrast, subterranean biotopes are highly thermally buffered (+/-1 degrees C within a year), and underground water organisms could thus be particularly well suited to characterise cellular responses of global warming. To this purpose, we studied genes encoding chaperone proteins of the HSP70 family in amphipod crustaceans belonging to the ubiquitous subterranean genus Niphargus. An HSP70 sequence was identified in eight populations of two complexes of species of the Niphargus genus (Niphargus rhenorhodanensis and Niphargus virei complexes). Expression profiles were determined for one of these by reverse transcription and quantitative polymerase chain reaction, confirming the inducible nature of this gene. An increase in temperature of 2 degrees C seemed to be without effect on N. rhenorhodanensis physiology, whereas a heat shock of +6 degrees C represented an important thermal stress for these individuals. Thus, this study shows that although Niphargus individuals do not undergo any daily or seasonal thermal variations in underground water, they display an inducible HSP70 heat shock response. This controlled laboratory-based physiological experiment constitutes a first step towards field investigations of the cellular consequences of global warming on subterranean organisms.

  20. Effects of heated hydrotherapy on muscle HSP70 and glucose metabolism in old and young vervet monkeys.

    Science.gov (United States)

    Kavanagh, Kylie; Davis, Ashely T; Jenkins, Kurt A; Flynn, D Mickey

    2016-07-01

    Increasing heat shock protein 70 (HSP70) in aged and/or insulin-resistant animal models confers benefits to healthspan and lifespan. Heat application to increase core temperature induces HSPs in metabolically important tissues, and preliminary human and animal data suggest that heated hydrotherapy is an effective method to achieve increased HSPs. However, safety concerns exist, particularly in geriatric medicine where organ and cardiovascular disease commonly will preexist. We evaluated young vervet monkeys compared to old, insulin-resistant vervet monkeys (Chlorocebus aethiops sabaeus) in their core temperatures, glucose tolerance, muscle HSP70 level, and selected safety biomarkers after 10 sessions of hot water immersions administered twice weekly. Hot water immersion robustly induced the heat shock response in muscles. We observed that heat-treated old and young monkeys have significantly higher muscle HSP70 than control monkeys and treatment was without significant adverse effects on organ or cardiovascular health. Heat therapy improved pancreatic responses to glucose challenge and tended to normalize glucose excursions. A trend for worsened blood pressure and glucose values in the control monkeys and improved values in heat-treated monkeys were seen to support further investigation into the safety and efficacy of this intervention for metabolic syndrome or diabetes in young or old persons unable to exercise.

  1. Function of SSA subfamily of Hsp70 within and across species varies widely in complementing Saccharomyces cerevisiae cell growth and prion propagation.

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    Deepak Sharma

    2009-08-01

    Full Text Available The cytosol of most eukaryotic cells contains multiple highly conserved Hsp70 orthologs that differ mainly by their spatio-temporal expression patterns. Hsp70s play essential roles in protein folding, transport or degradation, and are major players of cellular quality control processes. However, while several reports suggest that specialized functions of Hsp70 orthologs were selected through evolution, few studies addressed systematically this issue.We compared the ability of Ssa1p-Ssa4p from Saccharomyces cerevisiae and Ssa5p-Ssa8p from the evolutionary distant yeast Yarrowia lipolytica to perform Hsp70-dependent tasks when expressed as the sole Hsp70 for S. cerevisiae in vivo. We show that Hsp70 isoforms (i supported yeast viability yet with markedly different growth rates, (ii influenced the propagation and stability of the [PSI(+] and [URE3] prions, but iii did not significantly affect the proteasomal degradation rate of CFTR. Additionally, we show that individual Hsp70 orthologs did not induce the formation of different prion strains, but rather influenced the aggregation properties of Sup35 in vivo. Finally, we show that [URE3] curing by the overexpression of Ydj1p is Hsp70-isoform dependent.Despite very high homology and overlapping functions, the different Hsp70 orthologs have evolved to possess distinct activities that are required to cope with different types of substrates or stress situations. Yeast prions provide a very sensitive model to uncover this functional specialization and to explore the intricate network of chaperone/co-chaperone/substrates interactions.

  2. Genome-wide identification of heat shock proteins (Hsps) and Hsp interactors in rice: Hsp70s as a case study.

    Science.gov (United States)

    Wang, Yongfei; Lin, Shoukai; Song, Qi; Li, Kuan; Tao, Huan; Huang, Jian; Chen, Xinhai; Que, Shufu; He, Huaqin

    2014-05-07

    Heat shock proteins (Hsps) perform a fundamental role in protecting plants against abiotic stresses. Although researchers have made great efforts on the functional analysis of individual family members, Hsps have not been fully characterized in rice (Oryza sativa L.) and little is known about their interactors. In this study, we combined orthology-based approach with expression association data to screen rice Hsps for the expression patterns of which strongly correlated with that of heat responsive probe-sets. Twenty-seven Hsp candidates were identified, including 12 small Hsps, six Hsp70s, three Hsp60s, three Hsp90s, and three clpB/Hsp100s. Then, using a combination of interolog and expression profile-based methods, we inferred 430 interactors of Hsp70s in rice, and validated the interactions by co-localization and function-based methods. Subsequent analysis showed 13 interacting domains and 28 target motifs were over-represented in Hsp70s interactors. Twenty-four GO terms of biological processes and five GO terms of molecular functions were enriched in the positive interactors, whose expression levels were positively associated with Hsp70s. Hsp70s interaction network implied that Hsp70s were involved in macromolecular translocation, carbohydrate metabolism, innate immunity, photosystem II repair and regulation of kinase activities. Twenty-seven Hsps in rice were identified and 430 interactors of Hsp70s were inferred and validated, then the interacting network of Hsp70s was induced and the function of Hsp70s was analyzed. Furthermore, two databases named Rice Heat Shock Proteins (RiceHsps) and Rice Gene Expression Profile (RGEP), and one online tool named Protein-Protein Interaction Predictor (PPIP), were constructed and could be accessed at http://bioinformatics.fafu.edu.cn/.

  3. Multifunctional selenium nanoparticles as carriers of HSP70 siRNA to induce apoptosis of HepG2 cells

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    Li Y

    2016-07-01

    Full Text Available Yinghua Li,1 Zhengfang Lin,1 Mingqi Zhao,1 Tiantian Xu,1 Changbing Wang,1 Huimin Xia,1,* Hanzhong Wang,2,* Bing Zhu1,* 1Guangzhou Women and Children’s Medical Center, Guangzhou, Guangdong, 2State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, People’s Republic of China *These authors contributed equally to this work Abstract: Small interfering RNA (siRNA as a new therapeutic modality holds promise for cancer treatment, but it is unable to cross cell membrane. To overcome this limitation, nanotechnology has been proposed for mediation of siRNA transfection. Selenium (Se is a vital dietary trace element for mammalian life and plays an essential role in the growth and functioning of humans. As a novel Se species, Se nanoparticles have attracted more and more attention for their higher anticancer efficacy. In the present study, siRNAs with polyethylenimine (PEI-modified Se nanoparticles (Se@PEI@siRNA have been demonstrated to enhance the apoptosis of HepG2 cells. Heat shock protein (HSP-70 is overexpressed in many types of human cancer and plays a significant role in several biological processes including the regulation of apoptosis. The objective of this study was to silence inducible HSP70 and promote the apoptosis of Se-induced HepG2 cells. Se@PEI@siRNA were successfully prepared and characterized by various microscopic methods. Se@PEI@siRNA showed satisfactory size distribution, high stability, and selectivity between cancer and normal cells. The cytotoxicity of Se@PEI@siRNA was lower for normal cells than tumor cells, indicating that these compounds may have fewer side effects. The gene-silencing efficiency of Se@PEI@siRNA was significantly much higher than Lipofectamine 2000@siRNA and resulted in a significantly reduced HSP70 mRNA and protein expression in cancer cells. When the expression of HSP70 was diminished, the function of cell protection was also removed and cancer cells became more

  4. Chaperone-Mediated Regulation of Choline Acetyltransferase Protein Stability and Activity by HSC/HSP70, HSP90, and p97/VCP

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    Trevor M. Morey

    2017-12-01

    Full Text Available Choline acetyltransferase (ChAT synthesizes the neurotransmitter acetylcholine in cholinergic neurons, and mutations of this enzyme are linked to the neuromuscular disorder congenital myasthenic syndrome (CMS. One CMS-related mutation, V18M, reduces ChAT enzyme activity and cellular protein levels, and is located within a highly-conserved N-terminal proline-rich motif at residues 14PKLPVPP20. We showed previously that disruption of this proline-rich motif by either proline-to-alanine mutation (P17A/P19A or mutation of residue Val18 (V18M enhances ubiquitination and degradation of these mutant ChAT proteins expressed in cholinergic SN56 cells by an unknown mechanism. In this study, using proximity-dependent biotin identification (BioID, co-immunoprecipitation and in situ proximity-ligation assay (PLA, we identified the heat shock proteins (HSPs HSC/HSP70 and HSP90 as novel ChAT protein-interactors. These molecular chaperones are well-known for promoting the folding and stabilization of cellular proteins. Thus, we found that inhibition of HSPs by treatment of cells with either the HSC/HSP70 inhibitors 2-phenylethynesulfonamide (PES or VER-155008, or the HSP90 inhibitor 17-AAG reduced cellular ChAT activity and solubility, and enhanced the ubiquitination and proteasome-dependent loss of ChAT protein. Importantly, the effects of HSP inhibition were greater for mutant ChAT proteins (P17A/P19A-ChAT and CMS-related V18M- and A513T-ChAT compared to wild-type ChAT. HSPs can promote ubiquitination and degradation of terminally misfolded proteins through cooperative interaction with the E3 ubiquitin ligase CHIP/Stub1, and while we show that ChAT interacts with CHIP in situ, siRNA-mediated knock-down of CHIP had no effect on either wild-type or mutant ChAT protein levels. However, inhibition of the endoplasmic reticulum (ER- and HSP-associated co-chaperone p97/VCP prevented degradation of ubiquitinated ChAT. Together, these results identify novel mechanisms

  5. Hsp 70 and 90 proteins as bio indicators of stress and protein damage in human lymphocytes exposed to neutrons; Proteinas Hsp 70 y 90 como bioindicadores de estres y dano proteico en linfocitos humanos expuestos a neutrones

    Energy Technology Data Exchange (ETDEWEB)

    Delgado, C. E.; Letechipia de L, C.; Vega C, H. R.; Sanchez R, S. H., E-mail: rmfranccesco00223@hotmail.com [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas, Zac. (Mexico)

    2016-09-15

    Neutrons, when interacting with the cells of the body produce free radicals, so that exposure to high doses of ionizing radiation can cause different damage to the body that can cause cell death, therefore, these effects will depend on the amount of dose, time and individual factors such as gender, age, health status and nutrition. Therefore, knowledge of cellular responses to radiation exposure is critical for developing predictive markers useful for assessing people's exposure to radiation. The purpose of this study was to estimate the cellular protein damage through the Hsp 70 and 90 proteins exposed to neutrons in human lymphocytes from clinically healthy subjects. The cell tissue was obtained by venipuncture, the lymphocytes were separated by Ficoll-Paque concentration gradient, the experimental batches were formed, thus having 5 duplicate samples, subjected to neutron irradiation in a {sup 242}Am-Be at doses of 0.25, 0.50, 0.75, 1 and 1.25 μGy at three distances 20, 21.5 and 23 cm. As a positive control, a sample exposed to heat (40 degrees Celsius) was used for 40 min. The proteins of the experimental batch were analyzed by Western-Blot and protein quantification was analyzed by densitometry, on the other hand the oxidative stress was quantified by Oxi-Blot. Was found that the neutrons at doses of 0.25 and 0.5 μGy over expressed the Hsp-70 proteins, but for Hsp-90 no over-dose expressed, there was no protein damage at the exposure doses that were established. It can be estimated that Hsp-70 proteins can serve as bio indicators of cell stress by exposure doses of 0.25 and 0.5 μGy of neutrons. (Author)

  6. Dynamics of the association of heat shock protein HSPA6 (Hsp70B') and HSPA1A (Hsp70-1) with stress-sensitive cytoplasmic and nuclear structures in differentiated human neuronal cells.

    Science.gov (United States)

    Shorbagi, Sadek; Brown, Ian R

    2016-11-01

    Heat shock proteins (Hsps) are cellular repair agents that counter the effects of protein misfolding that is a characteristic feature of neurodegenerative diseases. HSPA1A (Hsp70-1) is a widely studied member of the HSPA (Hsp70) family. The little-studied HSPA6 (Hsp70B') is present in the human genome and absent in mouse and rat; hence, it is missing in current animal models of neurodegenerative diseases. Differentiated human neuronal SH-SY5Y cells were employed to compare the dynamics of the association of YFP-tagged HSPA6 and HSPA1A with stress-sensitive cytoplasmic and nuclear structures. Following thermal stress, live-imaging confocal microscopy and Fluorescence Recovery After Photobleaching (FRAP) demonstrated that HSPA6 displayed a prolonged and more dynamic association, compared to HSPA1A, with centrioles that play critical roles in neuronal polarity and migration. HSPA6 and HSPA1A also targeted nuclear speckles, rich in RNA splicing factors, and the granular component of the nucleolus that is involved in rRNA processing and ribosomal subunit assembly. HSPA6 and HSPA1A displayed similar FRAP kinetics in their interaction with nuclear speckles and the nucleolus. Subsequently, during the recovery from neuronal stress, HSPA6, but not HSPA1A, localized with the periphery of nuclear speckles (perispeckles) that have been characterized as transcription sites. The stress-induced association of HSPA6 with perispeckles displayed the greatest dynamism compared to the interaction of HSPA6 or HSPA1A with other stress-sensitive cytoplasmic and nuclear structures. This suggests involvement of HSPA6 in transcriptional recovery of human neurons from cellular stress that is not apparent for HSPA1A.

  7. Exercise Training under Exposure to Low Levels of Fine Particulate Matter: Effects on Heart Oxidative Stress and Extra-to-Intracellular HSP70 Ratio

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    Aline Sfalcin Mai

    2017-01-01

    Full Text Available Fine particulate matter (PM2.5 promotes heart oxidative stress (OS and evokes anti-inflammatory responses observed by increased intracellular 70 kDa heat shock proteins (iHSP70. Furthermore, PM2.5 increases the levels of these proteins in extracellular fluids (eHSP70, which have proinflammatory roles. We investigated whether moderate and high intensity training under exposure to low levels of PM2.5 modifies heart OS and the eHSP70 to iHSP70 ratio (H-index, a biomarker of inflammatory status. Male mice (n=32, 30 days old, were divided into six groups for 12 weeks: control (CON, moderate (MIT and high intensity training (HIT, exposure to 5 μg of PM2.5 daily (PM2.5, and moderate and high intensity training exposed to PM2.5 (MIT + PM2.5 and HIT + PM2.5 groups. The CON and PM2.5 groups remained sedentary. The MIT + PM2.5 group showed higher heart lipid peroxidation levels than the MIT and PM2.5 groups. HIT and HIT + PM2.5 showed higher heart lipid peroxidation levels and lower eHSP70 and H-index levels compared to sedentary animals. No alterations were found in heart antioxidant enzyme activity or iHSP70 levels. Moderate exercise training under exposure to low levels of PM2.5 induces heart OS but does not modify eHSP70 to iHSP70 ratio (H-index. High intensity exercise training promotes anti-inflammatory profile despite exposure to low levels of PM2.5.

  8. Non-lethal heat shock increased Hsp70 and immune protein transcripts but not Vibrio tolerance in the white-leg shrimp.

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    Nguyen Hong Loc

    Full Text Available Non-lethal heat shock boosts bacterial and viral disease tolerance in shrimp, possibly due to increases in endogenous heat shock protein 70 (Hsp70 and/or immune proteins. To further understand the mechanisms protecting shrimp against infection, Hsp70 and the mRNAs encoding the immune-related proteins prophenoloxidase (proPO, peroxinectin, penaeidin, crustin and hemocyanin were studied in post-larvae of the white-leg shrimp Litopenaeus vannamei, following a non-lethal heat shock. As indicated by RT-qPCR, a 30 min abrupt heat shock increased Hsp70 mRNA in comparison to non-heated animals. Immunoprobing of western blots and quantification by ELISA revealed that Hsp70 production after heat shock was correlated with enhanced Hsp70 mRNA. proPO and hemocyanin mRNA levels were augmented, whereas peroxinectin and crustin mRNA levels were unchanged following non-lethal heat shock. Penaeidin mRNA was decreased by all heat shock treatments. Thirty min abrupt heat shock failed to improve survival of post-larvae in a standardized challenge test with Vibrio harveyi, indicating that under the conditions of this study, L. vannamei tolerance to Vibrio infection was influenced neither by Hsp70 accumulation nor the changes in the immune-related proteins, observations dissimilar to other shrimp species examined.

  9. Non-Lethal Heat Shock Increased Hsp70 and Immune Protein Transcripts but Not Vibrio Tolerance in the White-Leg Shrimp

    Science.gov (United States)

    Loc, Nguyen Hong; MacRae, Thomas H.; Musa, Najiah; Bin Abdullah, Muhd Danish Daniel; Abdul Wahid, Mohd. Effendy; Sung, Yeong Yik

    2013-01-01

    Non-lethal heat shock boosts bacterial and viral disease tolerance in shrimp, possibly due to increases in endogenous heat shock protein 70 (Hsp70) and/or immune proteins. To further understand the mechanisms protecting shrimp against infection, Hsp70 and the mRNAs encoding the immune-related proteins prophenoloxidase (proPO), peroxinectin, penaeidin, crustin and hemocyanin were studied in post-larvae of the white-leg shrimp Litopenaeus vannamei, following a non-lethal heat shock. As indicated by RT-qPCR, a 30 min abrupt heat shock increased Hsp70 mRNA in comparison to non-heated animals. Immunoprobing of western blots and quantification by ELISA revealed that Hsp70 production after heat shock was correlated with enhanced Hsp70 mRNA. proPO and hemocyanin mRNA levels were augmented, whereas peroxinectin and crustin mRNA levels were unchanged following non-lethal heat shock. Penaeidin mRNA was decreased by all heat shock treatments. Thirty min abrupt heat shock failed to improve survival of post-larvae in a standardized challenge test with Vibrio harveyi, indicating that under the conditions of this study, L. vannamei tolerance to Vibrio infection was influenced neither by Hsp70 accumulation nor the changes in the immune-related proteins, observations dissimilar to other shrimp species examined. PMID:24039886

  10. BAG3 Is a Modular, Scaffolding Protein that physically Links Heat Shock Protein 70 (Hsp70) to the Small Heat Shock Proteins.

    Science.gov (United States)

    Rauch, Jennifer N; Tse, Eric; Freilich, Rebecca; Mok, Sue-Ann; Makley, Leah N; Southworth, Daniel R; Gestwicki, Jason E

    2017-01-06

    Small heat shock proteins (sHsps) are a family of ATP-independent molecular chaperones that are important for binding and stabilizing unfolded proteins. In this task, the sHsps have been proposed to coordinate with ATP-dependent chaperones, including heat shock protein 70 (Hsp70). However, it is not yet clear how these two important components of the chaperone network are linked. We report that the Hsp70 co-chaperone, BAG3, is a modular, scaffolding factor to bring together sHsps and Hsp70s. Using domain deletions and point mutations, we found that BAG3 uses both of its IPV motifs to interact with sHsps, including Hsp27 (HspB1), αB-crystallin (HspB5), Hsp22 (HspB8), and Hsp20 (HspB6). BAG3 does not appear to be a passive scaffolding factor; rather, its binding promoted de-oligomerization of Hsp27, likely by competing for the self-interactions that normally stabilize large oligomers. BAG3 bound to Hsp70 at the same time as Hsp22, Hsp27, or αB-crystallin, suggesting that it might physically bring the chaperone families together into a complex. Indeed, addition of BAG3 coordinated the ability of Hsp22 and Hsp70 to refold denatured luciferase in vitro. Together, these results suggest that BAG3 physically and functionally links Hsp70 and sHsps. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. Sense and antisense transcripts of the developmentally regulated murine hsp70.2 gene are expressed in distinct and only partially overlapping areas in the adult brain

    Science.gov (United States)

    Murashov, A. K.; Wolgemuth, D. J.

    1996-01-01

    We have examined the spatial pattern of expression of a member of the hsp70 gene family, hsp70.2, in the mouse central nervous system. Surprisingly, RNA blot analysis and in situ hybridization revealed abundant expression of an 'antisense' hsp70.2 transcript in several areas of adult mouse brain. Two different transcripts recognized by sense and antisense riboprobes for the hsp70.2 gene were expressed in distinct and only partially overlapping neuronal populations. RNA blot analysis revealed low levels of the 2.7 kb transcript of hsp70.2 in several areas of the brain, with highest signal in the hippocampus. Abundant expression of a slightly larger (approximately 2.8 kb) 'antisense' transcript was detected in several brain regions, notably in the brainstem, cerebellum, mesencephalic tectum, thalamus, cortex, and hippocampus. In situ hybridization revealed that the sense and antisense transcripts were both predominantly neuronal and localized to the same cell types in the granular layer of the cerebellum, trapezoid nucleus of the superior olivary complex, locus coeruleus and hippocampus. The hsp70.2 antisense transcripts were particularly abundant in the frontal cortex, dentate gyrus, subthalamic nucleus, zona incerta, superior and inferior colliculi, central gray, brainstem, and cerebellar Purkinje cells. Our findings have revealed a distinct cellular and spatial localization of both sense and antisense transcripts, demonstrating a new level of complexity in the function of the heat shock genes.

  12. Curcuma purpurascens BI. rhizome accelerates rat excisional wound healing: involvement of Hsp70/Bax proteins, antioxidant defense, and angiogenesis activity

    Science.gov (United States)

    Rouhollahi, Elham; Moghadamtousi, Soheil Zorofchian; Hajiaghaalipour, Fatemeh; Zahedifard, Maryam; Tayeby, Faezeh; Awang, Khalijah; Abdulla, Mahmood Ameen; Mohamed, Zahurin

    2015-01-01

    Purpose Curcuma purpurascens BI. is a member of Zingiberaceae family. The purpose of this study is to investigate the wound healing properties of hexane extract of C. purpurascens rhizome (HECP) against excisional wound healing in rats. Materials and methods Twenty four rats were randomly divided into 4 groups: A) negative control (blank placebo, acacia gum), B) low dose of HECP, C) high dose of HECP, and D) positive control, with 6 rats in each group. Full-thickness incisions (approximately 2.00 cm) were made on the neck area of each rat. Groups 1–4 were treated two-times a day for 20 days with blank placebo, HECP (100 mg/kg), HECP (200 mg/kg), and intrasite gel as a positive control, respectively. After 20 days, hematoxylin and eosin and Masson’s trichrome stainings were employed to investigate the histopathological alterations. Protein expressions of Bax and Hsp70 were examined in the wound tissues using immunohistochemistry analysis. In addition, levels of enzymatic antioxidants and malondialdehyde representing lipid peroxidation were measured in wound tissue homogenates. Results Macroscopic evaluation of wounds showed conspicuous elevation in wound contraction after topical administration of HECP at both doses. Moreover, histopathological analysis revealed noteworthy reduction in the scar width correlated with the enhanced collagen content and fibroblast cells, accompanied by a reduction of inflammatory cells in the granulation tissues. At the molecular level, HECP facilitates wound-healing process by downregulating Bax and upregulating Hsp70 protein at the wound site. The formation of new blood vessel was observed in Masson’s trichrome staining of wounds treated with HECP (100 and 200 mg/kg). In addition, HECP administration caused a significant surge in enzymatic antioxidant activities and a decline in lipid peroxidation. Conclusion These findings suggested that HECP accelerated wound-healing process in rats via antioxidant activity, angiogenesis

  13. C-terminal sequences of hsp70 and hsp90 as non-specific anchors for tetratricopeptide repeat (TPR) proteins.

    Science.gov (United States)

    Ramsey, Andrew J; Russell, Lance C; Chinkers, Michael

    2009-10-12

    Steroid-hormone-receptor maturation is a multi-step process that involves several TPR (tetratricopeptide repeat) proteins that bind to the maturation complex via the C-termini of hsp70 (heat-shock protein 70) and hsp90 (heat-shock protein 90). We produced a random T7 peptide library to investigate the roles played by the C-termini of the two heat-shock proteins in the TPR-hsp interactions. Surprisingly, phages with the MEEVD sequence, found at the C-terminus of hsp90, were not recovered from our biopanning experiments. However, two groups of phages were isolated that bound relatively tightly to HsPP5 (Homo sapiens protein phosphatase 5) TPR. Multiple copies of phages with a C-terminal sequence of LFG were isolated. These phages bound specifically to the TPR domain of HsPP5, although mutation studies produced no evidence that they bound to the domain's hsp90-binding groove. However, the most abundant family obtained in the initial screen had an aspartate residue at the C-terminus. Two members of this family with a C-terminal sequence of VD appeared to bind with approximately the same affinity as the hsp90 C-12 control. A second generation pseudo-random phage library produced a large number of phages with an LD C-terminus. These sequences acted as hsp70 analogues and had relatively low affinities for hsp90-specific TPR domains. Unfortunately, we failed to identify residues near hsp90's C-terminus that impart binding specificity to individual hsp90-TPR interactions. The results suggest that the C-terminal sequences of hsp70 and hsp90 act primarily as non-specific anchors for TPR proteins.

  14. Hsp 70 and 90 proteins as bio indicators of stress and protein damage in human lymphocytes exposed to neutrons

    International Nuclear Information System (INIS)

    Delgado, C. E.; Letechipia de L, C.; Vega C, H. R.; Sanchez R, S. H.

    2016-09-01

    Neutrons, when interacting with the cells of the body produce free radicals, so that exposure to high doses of ionizing radiation can cause different damage to the body that can cause cell death, therefore, these effects will depend on the amount of dose, time and individual factors such as gender, age, health status and nutrition. Therefore, knowledge of cellular responses to radiation exposure is critical for developing predictive markers useful for assessing people's exposure to radiation. The purpose of this study was to estimate the cellular protein damage through the Hsp 70 and 90 proteins exposed to neutrons in human lymphocytes from clinically healthy subjects. The cell tissue was obtained by venipuncture, the lymphocytes were separated by Ficoll-Paque concentration gradient, the experimental batches were formed, thus having 5 duplicate samples, subjected to neutron irradiation in a "2"4"2Am-Be at doses of 0.25, 0.50, 0.75, 1 and 1.25 μGy at three distances 20, 21.5 and 23 cm. As a positive control, a sample exposed to heat (40 degrees Celsius) was used for 40 min. The proteins of the experimental batch were analyzed by Western-Blot and protein quantification was analyzed by densitometry, on the other hand the oxidative stress was quantified by Oxi-Blot. Was found that the neutrons at doses of 0.25 and 0.5 μGy over expressed the Hsp-70 proteins, but for Hsp-90 no over-dose expressed, there was no protein damage at the exposure doses that were established. It can be estimated that Hsp-70 proteins can serve as bio indicators of cell stress by exposure doses of 0.25 and 0.5 μGy of neutrons. (Author)

  15. Effects of aspartame on hsp70, bcl-2 and bax expression in immune organs of Wistar albino rats

    Science.gov (United States)

    Choudhary, Arbind Kumar; Devi, Rathinasamy Sheela

    2016-01-01

    Abstract Aspartame, a “first generation sweetener”, is widely used in a variety of foods, beverages, and medicine. The FDA has determined the acceptable daily intake (ADI) value of aspartame to be 50 mg/kg·day, while the JECFA (Joint FAO/WHO Expert Committee on Food Additives) has set this value at 40 mg/kg of body weight/day. Safety issues have been raised about aspartame due to its metabolites, specifically toxicity from methanol and/or its systemic metabolites formaldehyde and formic acid. The immune system is now recognized as a target organ for many xenobiotics, such as drugs and chemicals, which are able to trigger unwanted apoptosis or to alter the regulation of apoptosis. Our previous studies has shown that oral administration of aspartame [40 mg/(kg·day)] or its metabolites for 90 days increased oxidative stress in immune organs of Wistar albino rats. In this present study, we aimed to clarify whether aspartame consumption over a longer period (90-days) has any effect on the expression of hsp70, bcl-2 and bax at both mRNA transcript and protein expression levels in immune organs. We observed that oral administration of aspartame for 90 days did not cause any apparent DNA fragmentation in immune organs of aspartame treated animals; however, there was a significant increase in hsp70 expression, apart from significant alteration in bcl-2 and bax at both mRNA transcript and protein expression level in the immune organs of aspartame treated animals compared to controls. Hence, the results indicated that hsp70 levels increased in response to oxidative injury induced by aspartame metabolites; however, these metabolites did not induce apoptosis in the immune organs. Furthermore, detailed analyses are needed to elucidate the precise molecular mechanisms involved in these changes. PMID:27845306

  16. Evidence for loss of mitochondria in Microsporidia from a mitochondrial-type HSP70 in Nosema locustae.

    Science.gov (United States)

    Germot, A; Philippe, H; Le Guyader, H

    1997-08-01

    In molecular phylogenies based on ribosomal RNA, three amitochondriate protist lineages, Microsporidia, Metamonada (including diplomonads) and Parabasala (including trichomonads), are the earliest offshoots of the eukaryotic tree. As an explantation for the lack of mitochondria in these organisms, the hypothesis that they have diverged before the mitochondrial endosymbiosis is preferred to the less parsimonious hypothesis of several independent losses of the organelle. Nevertheless, if they had descended from mitochondrion-containing ancestors, it may be possible to find in their nuclear DNA genes that derive from the endosymbiont which gave rise to mitochondria. Based on similar evidence, secondary losses of mitochondria have recently been suggested for Entamoeba histolytica and for Trichomonas vaginalis. In this study, we have isolated a gene encoding a chaperone protein (HSP70, 70 kDa heat shock protein) from the microspordian Nosema locustae. In phylogenetic trees, this HSP70 was located within a group of sequences that in other lineages is targetted to the mitochondrial compartment, itself included in the proteobacterial clade. In addition, the N. locustae protein contained the GDAW(V) motif shared by mitochondrial and proteobacterial sequences, with only one conservative substitution. Moreover, microsporidia, a phylum which was assumed to emerge close to the base of the eukaryotic tree, appears as the sister-group of fungi in the HSP70 phylogeny, in agreement with some ultrastructural characters and phylogenies based on alpha- and beta-tubulins. Loss of mitochondria, now demonstrated for several amitochondriate groups, indicates that the common ancestor of all the extant eukaryotic species could have been a mitochondriate eukaryote.

  17. A fraction from Petiveria alliacea induces apoptosis via a mitochondria-dependent pathway and regulates HSP70 expression

    OpenAIRE

    Cifuentes, Maria Claudia; Grupo de Inmunobiología y Biología Celular, Facultad de Ciencias, Pontificia Universidad Javeriana, Bogotá; Castañeda, Diana Mercedes; Grupo de Inmunobiología y Biología Celular, Facultad de Ciencias, Pontificia Universidad Javeriana, Bogotá; Urueña, Claudia Patricia; Grupo de Inmunobiología y Biología Celular, Facultad de Ciencias, Pontificia Universidad Javeriana, Bogotá; Fiorentino, Susana; Grupo de Inmunobiología y Biología Celular, Facultad de Ciencias, Pontificia Universidad Javeriana, Bogotá

    2009-01-01

    Una fracción de Petiveria alliacea induce apoptosis dependiente de la mitocondria y regula la expresión de la proteína HSP70. Objetivo: Evaluar la actividad biológica in vitro de extractos de Petiveria alliacea utilizando líneas celulares tumorales. Materiales y Métodos: Las fracciones de P.alliacea fueron preparadas mediante un protocolo de purificación biodirigido. La actividad biológica fue caracterizada utilizando dos líneas celulares tumorales de origen humano, donde se analizaron los ca...

  18. Extrapolation of Inter Domain Communications and Substrate Binding Cavity of Camel HSP70 1A: A Molecular Modeling and Dynamics Simulation Study.

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    Saurabh Gupta

    Full Text Available Heat shock protein 70 (HSP70 is an important chaperone, involved in protein folding, refolding, translocation and complex remodeling reactions under normal as well as stress conditions. However, expression of HSPA1A gene in heat and cold stress conditions associates with other chaperons and perform its function. Experimental structure for Camel HSP70 protein (cHSP70 has not been reported so far. Hence, we constructed 3D models of cHSP70 through multi- template comparative modeling with HSP110 protein of S. cerevisiae (open state and with HSP70 protein of E. coli 70kDa DnaK (close state and relaxed them for 100 nanoseconds (ns using all-atom Molecular Dynamics (MD Simulation. Two stable conformations of cHSP70 with Substrate Binding Domain (SBD in open and close states were obtained. The collective mode analysis of different transitions of open state to close state and vice versa was examined via Principal Component Analysis (PCA and Minimum Distance Matrix (MDM. The results provide mechanistic representation of the communication between Nucleotide Binding Domain (NBD and SBD to identify the role of sub domains in conformational change mechanism, which leads the chaperone cycle of cHSP70. Further, residues present in the chaperon functioning site were also identified through protein-peptide docking. This study provides an overall insight into the inter domain communication mechanism and identification of the chaperon binding cavity, which explains the underlying mechanism involved during heat and cold stress conditions in camel.

  19. Fine particulate matter potentiates type 2 diabetes development in high-fat diet-treated mice: stress response and extracellular to intracellular HSP70 ratio analysis.

    Science.gov (United States)

    Goettems-Fiorin, Pauline Brendler; Grochanke, Bethânia Salamoni; Baldissera, Fernanda Giesel; Dos Santos, Analu Bender; Homem de Bittencourt, Paulo Ivo; Ludwig, Mirna Stela; Rhoden, Claudia Ramos; Heck, Thiago Gomes

    2016-12-01

    Exposure to fine particulate matter (PM 2.5 ) air pollution is a risk factor for type 2 diabetes (T2DM). We argue whether the potentiating effect of PM 2.5 over the development of T2DM in high-fat diet (HFD)-fed mice would be related to modification in cell stress response, particularly in antioxidant defenses and 70-kDa heat shock proteins (HSP70) status. Male mice were fed standard chow or HFD for 12 weeks and then randomly exposed to daily nasotropic instillation of PM 2.5 for additional 12 weeks under the same diet schedule, divided into four groups (n = 14-15 each): Control, PM 2.5 , HFD, and HFD + PM 2.5 were evaluated biometric and metabolic profiles of mice, and cellular stress response (antioxidant defense and HSP70 status) of metabolic tissues. Extracellular to intracellular HSP70 ratio ([eHSP72]/[iHSP70]), viz. H-index, was then calculated. HFD + PM 2.5 mice presented a positive correlation between adiposity, increased body weight and glucose intolerance, and increased glucose and triacylglycerol plasma levels. Pancreas exhibited lower iHSP70 expression, accompanied by 3.7-fold increase in the plasma to pancreas [eHSP72]/[iHSP70] ratio. Exposure to PM 2.5 markedly potentiated metabolic dysfunction in HFD-treated mice and promoted relevant alteration in cell stress response assessed by [eHSP72]/[iHSP70], a relevant biomarker of chronic low-grade inflammatory state and T2DM risk.

  20. RNA polymerase II interacts with the promoter region of the noninduced hsp70 gene in Drosophila melanogaster cells

    International Nuclear Information System (INIS)

    Gilmour, D.S.; Lis, J.T.

    1986-01-01

    By using a protein-DNA cross-linking method, we examined the in vivo distribution of RNA polymerase II on the hsp70 heat shock gene in Drosophila melanogaster Schneider line 2 cells. In heat shock-induced cells, a high level of RNA polymerase II was detected on the entire gene, while in noninduced cells, the RNA polymerase II was confined to the 5' end of the hsp70 gene, predominantly between nucleotides -12 and +65 relative to the start of transcription. This association of RNA polymerase II was apparent whether the cross-linking was performed by a 10-min UV irradiation of chilled cells with mercury vapor lamps or by a 40-microsecond irradiation of cells with a high-energy xenon flash lamp. We hypothesize that RNA polymerase II has access to, and a high affinity for, the promoter region of this gene before induction, and this poised RNA polymerase II may be critical in the mechanism of transcription activation

  1. Expression of Hsp27 and Hsp70 and vacuolization in the pituitary glands in cases of fatal hypothermia.

    Science.gov (United States)

    Doberentz, Elke; Markwerth, Philipp; Wagner, Rebecca; Madea, Burkhard

    2017-09-01

    Hypothermia causes systemic cellular stress. The pituitary gland is an endocrine gland and plays an important role in thermoregulation. When the core body temperature drops, the pituitary gland is activated by stimulation of hypothalamic hormones. In this study, we investigated morphological alterations of the pituitary gland in cases of fatal hypothermia. Several morphological alterations of the anterior lobe of the pituitary gland, such as hemorrhage, vacuolization, and hyperemia, have been previously described in fatal hypothermia. However, the diagnostic value of these findings is controversial. We compared 11 cases of fatal hypothermia with 10 cases lacking antemortem hypothermic influences. In the presence of thermal cellular stress, the expression of heat shock proteins increases to protect cellular structures. Therefore, we immunohistochemically analyzed Hsp27 and Hsp70. Hsp27 expression was detected in 27.3% of the cases of fatal hypothermia and in 10.0% of the control cases, whereas Hsp70 expression was not detected in any case. Additionally, Sudan staining was performed to quantify fatty degeneration. A positive reaction was found in 45.5% of the study group and in 10.0% of the control group. This indicates that fatty degeneration might be a valuable marker when other macroscopic signs of hypothermia are absent.

  2. Sequential folding of UmuC by the Hsp70 and Hsp60 chaperone complexes of Escherichia coli.

    Science.gov (United States)

    Petit, M A; Bedale, W; Osipiuk, J; Lu, C; Rajagopalan, M; McInerney, P; Goodman, M F; Echols, H

    1994-09-23

    Replication-blocking lesions generate a signal in Escherichia coli that leads to the induction of the multigene SOS response. Among the SOS-induced genes are umuD and umuC, whose products are necessary for the increased mutation rate in induced bacteria. The mutations are likely to result from replication across the DNA lesion, and such a bypass event has been reconstituted in vitro (Rajagopalan, M., L, C., Woodgate, R., O'Donnel, M., Goodman, M. F., Echols, H. (1992) Proc. Natl. Acad. Sci. U.S.A. 89, 10777-10781). In this work, we show that the chaperone proteins promote the proper folding of UmuC protein in vitro. We treated purified and inactive UmuC with Hsp70 and Hsp60. After Hsp70 treatment, the DNA binding activity of UmuC was recovered, but the ability to promote replication across DNA lesions was not. However, lesion bypass activity was recovered upon further treatment with Hsp60. The biological significance of such a folding pathway for UmuC protein is strengthened by in vivo evidence for a role of DnaK in UV-induced mutagenesis.

  3. An ELISA using recombinant TmHSP70 for the diagnosis of Taenia multiceps infections in goats.

    Science.gov (United States)

    Wang, Yu; Nie, Huaming; Gu, Xiaobin; Wang, Tao; Huang, Xing; Chen, Lin; Lai, Weimin; Peng, Xuerong; Yang, Guangyou

    2015-09-15

    Infections with the tapeworm Taenia multiceps are problematic for ruminant farming worldwide. Here we develop a novel and rapid method for serodiagnosis of T. multiceps infections via an indirect ELISA (iELISA) that uses a heat shock protein, namely, TmHSP70. We extracted the total RNA of T. multiceps from the protoscoleces of cysts dissected from the brains of infected goats. Subsequently, we successfully amplified, cloned and expressed the TmHSP70 gene in Escherichia coli BL21 (DE3). Western blot analysis showed that the recombinant protein (∼34 kDa molecular weight) was recognized by the coenurosis positive serum. Given these initial, robust immunogenic properties for recombinant TmHSP protein, we assessed the ELISA-based serodiagnostic potential of this gene. The indirect ELISA was then optimized to 2.70 μg/well dilution for antigen and 1:80 dilution for serum,while the cut-off value is 0.446. We report that our novel TmHSP ELISA detected T. multiceps sera with a sensitivity of 1:10240 and a specificity of 83.3% (5/6). In a preliminary application, this assay correctly confirmed T. multiceps infection in 30 infected goats, consistent with the clinical examination. This study has revealed that our novel iELISA, which uses the rTmHSP protein, provides a rapid test for diagnosing coenurosis. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. High Resolution Melting Analysis Targeting hsp70 as a Fast and Efficient Method for the Discrimination of Leishmania Species.

    Science.gov (United States)

    Zampieri, Ricardo Andrade; Laranjeira-Silva, Maria Fernanda; Muxel, Sandra Marcia; Stocco de Lima, Ana Carolina; Shaw, Jeffrey Jon; Floeter-Winter, Lucile Maria

    2016-02-01

    Protozoan parasites of the genus Leishmania cause a large spectrum of clinical manifestations known as Leishmaniases. These diseases are increasingly important public health problems in many countries both within and outside endemic regions. Thus, an accurate differential diagnosis is extremely relevant for understanding epidemiological profiles and for the administration of the best therapeutic protocol. Exploring the High Resolution Melting (HRM) dissociation profiles of two amplicons using real time polymerase chain reaction (real-time PCR) targeting heat-shock protein 70 coding gene (hsp70) revealed differences that allowed the discrimination of genomic DNA samples of eight Leishmania species found in the Americas, including Leishmania (Leishmania) infantum chagasi, L. (L.) amazonensis, L. (L.) mexicana, L. (Viannia) lainsoni, L. (V.) braziliensis, L. (V.) guyanensis, L. (V.) naiffi and L. (V.) shawi, and three species found in Eurasia and Africa, including L. (L.) tropica, L. (L.) donovani and L. (L.) major. In addition, we tested DNA samples obtained from standard promastigote culture, naturally infected phlebotomines, experimentally infected mice and clinical human samples to validate the proposed protocol. HRM analysis of hsp70 amplicons is a fast and robust strategy that allowed for the detection and discrimination of all Leishmania species responsible for the Leishmaniases in Brazil and Eurasia/Africa with high sensitivity and accuracy. This method could detect less than one parasite per reaction, even in the presence of host DNA.

  5. High Resolution Melting Analysis Targeting hsp70 as a Fast and Efficient Method for the Discrimination of Leishmania Species.

    Directory of Open Access Journals (Sweden)

    Ricardo Andrade Zampieri

    2016-02-01

    Full Text Available Protozoan parasites of the genus Leishmania cause a large spectrum of clinical manifestations known as Leishmaniases. These diseases are increasingly important public health problems in many countries both within and outside endemic regions. Thus, an accurate differential diagnosis is extremely relevant for understanding epidemiological profiles and for the administration of the best therapeutic protocol.Exploring the High Resolution Melting (HRM dissociation profiles of two amplicons using real time polymerase chain reaction (real-time PCR targeting heat-shock protein 70 coding gene (hsp70 revealed differences that allowed the discrimination of genomic DNA samples of eight Leishmania species found in the Americas, including Leishmania (Leishmania infantum chagasi, L. (L. amazonensis, L. (L. mexicana, L. (Viannia lainsoni, L. (V. braziliensis, L. (V. guyanensis, L. (V. naiffi and L. (V. shawi, and three species found in Eurasia and Africa, including L. (L. tropica, L. (L. donovani and L. (L. major. In addition, we tested DNA samples obtained from standard promastigote culture, naturally infected phlebotomines, experimentally infected mice and clinical human samples to validate the proposed protocol.HRM analysis of hsp70 amplicons is a fast and robust strategy that allowed for the detection and discrimination of all Leishmania species responsible for the Leishmaniases in Brazil and Eurasia/Africa with high sensitivity and accuracy. This method could detect less than one parasite per reaction, even in the presence of host DNA.

  6. Heat adaptation from regular hot water immersion decreases proinflammatory responses, HSP70 expression, and physical heat stress.

    Science.gov (United States)

    Yang, Fwu-Lin; Lee, Chia-Chi; Subeq, Yi-Maun; Lee, Chung-Jen; Ke, Chun-Yen; Lee, Ru-Ping

    2017-10-01

    Hot-water immersion (HWI) is a type of thermal therapy for treating various diseases. In our study, the physiological responses to occasional and regular HWI have been explored. The rats were divided into a control group, occasional group (1D), and regular group (7D). The 1D and 7D groups received 42°C during 15mins HWI for 1 and 7 days, respectively. The blood samples were collected for proinflammatory cytokines examinations, the heart, liver and kidney were excised for subsequent IHC analysis to measure the level of heat shock protein 70 (HSP70). The results revealed that the body temperature increased significantly during HWI on Day 3 and significantly declined on Days 6 and 7. For the 7D group, body weight, heart rate, hematocrit, platelet, osmolarity, and lactate level were lower than those in the 1D group. Furthermore, the levels of granulocyte counts, tumor necrosis factor-α, and interleukin-6 were lower in the 7D group than in the 1D group. The induction of HSP70 in the 1D group was higher than in the other groups. Physiological responses to occasional HWI are disadvantageous because of heat stress. However, adaptation to heat from regular HWI resulted in decreased proinflammatory responses and physical heat stress. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Molecular karyotype and chromosomal localization of genes encoding ß-tubulin, cysteine proteinase, hsp 70 and actin in Trypanosoma rangeli

    Directory of Open Access Journals (Sweden)

    CB Toaldo

    2001-01-01

    Full Text Available The molecular karyotype of nine Trypanosoma rangeli strains was analyzed by contour-clamped homogeneous electric field electrophoresis, followed by the chromosomal localization of ß-tubulin, cysteine proteinase, 70 kDa heat shock protein (hsp 70 and actin genes. The T. rangeli strains were isolated from either insects or mammals from El Salvador, Honduras, Venezuela, Colombia, Panama and southern Brazil. Also, T. cruzi CL-Brener clone was included for comparison. Despite the great similarity observed among strains from Brazil, the molecular karyotype of all T. rangeli strains analyzed revealed extensive chromosome polymorphism. In addition, it was possible to distinguish T. rangeli from T. cruzi by the chromosomal DNA electrophoresis pattern. The localization of ß-tubulin genes revealed differences among T. rangeli strains and confirmed the similarity between the isolates from Brazil. Hybridization assays using probes directed to the cysteine proteinase, hsp 70 and actin genes discriminated T. rangeli from T. cruzi, proving that these genes are useful molecular markers for the differential diagnosis between these two species. Numerical analysis based on the molecular karyotype data revealed a high degree of polymorphism among T. rangeli strains isolated from southern Brazil and strains isolated from Central and the northern South America. The T. cruzi reference strain was not clustered with any T. rangeli strain.

  8. A Recombinant Trivalent Fusion Protein F1-LcrV-HSP70(II) Augments Humoral and Cellular Immune Responses and Imparts Full Protection against Yersinia pestis.

    Science.gov (United States)

    Verma, Shailendra K; Batra, Lalit; Tuteja, Urmil

    2016-01-01

    Plague is one of the most dangerous infections in humans caused by Yersinia pestis, a Gram-negative bacterium. Despite of an overwhelming research success, no ideal vaccine against plague is available yet. It is well established that F1/LcrV based vaccine requires a strong cellular immune response for complete protection against plague. In our earlier study, we demonstrated that HSP70(II) of Mycobacterium tuberculosis modulates the humoral and cellular immunity of F1/LcrV vaccine candidates individually as well as in combinations in a mouse model. Here, we made two recombinant constructs caf1-lcrV and caf1-lcrV-hsp70(II). The caf1 and lcrV genes of Y. pestis and hsp70 domain II of M. tuberculosis were amplified by polymerase chain reaction. Both the recombinant constructs caf1-lcrV and caf1-lcrV-hsp70(II) were cloned in pET28a vector and expressed in Escherichia coli. The recombinant fusion proteins F1-LcrV and F1-LcrV-HSP70(II) were purified using Ni-NTA columns and formulated with alum to evaluate the humoral and cell mediated immune responses in mice. The protective efficacies of F1-LcrV and F1-LcrV-HSP70(II) were determined following challenge of immunized mice with 100 LD50 of Y. pestis through intraperitoneal route. Significant differences were noticed in the titers of IgG and it's isotypes, i.e., IgG1, IgG2b, and IgG3 in anti- F1-LcrV-HSP70(II) sera in comparison to anti-F1-LcrV sera. Similarly, significant differences were also noticed in the expression levels of IL-2, IFN-γ and TNF-α in splenocytes of F1-LcrV-HSP(II) immunized mice in comparison to F1-LcrV. Both F1-LcrV and F1-LcrV-HSP70(II) provided 100% protection. Our research findings suggest that F1-LcrV fused with HSP70 domain II of M. tuberculosis significantly enhanced the humoral and cellular immune responses in mouse model.

  9. Nickel, lead, and cadmium induce differential cellular responses in sea urchin embryos by activating the synthesis of different HSP70s

    International Nuclear Information System (INIS)

    Geraci, Fabiana; Pinsino, Annalisa; Turturici, Guiseppina; Savona, Rosalia; Giudice, Giovanni; Sconzo, Gabriella

    2004-01-01

    Treatment with heavy metals, such as nickel, lead or cadmium, elicits different cellular stress responses according to the metal used and the length of treatment. In Paracentrotus lividus embryos the inducible forms of HSP70 (HSP70/72) are different in molecular mass from the constitutively expressed HSP75, and they can be used as markers of cellular stress. Even a short treatment with each metal induces the synthesis of HSP70/72 which remain stable for at least 20 h and differ little in their isoelectric points. Continuous treatment from fertilization with nickel or lead produces late irregular pluteus embryos, with peak HSP70/72 synthesis at blastula followed by the arrest of synthesis by pluteus. On the contrary, the same treatment with cadmium induces continuous HSP70/72 synthesis and produces irregular gastrula embryos which then degenerate. Moreover, a long treatment induces over control embryos a slight increase in the amount of constitutive HSP75 during development while lead treatment depresses constitutive HSP75 at early stages and doubles its quantity at late stages

  10. ANTI-HSP60 and ANTI-HSP70 antibody levels and micro/ macrovascular complications in type 1 diabetes: the EURODIAB Study

    DEFF Research Database (Denmark)

    Gruden, G.; Bruno, G.; Chaturvedi, N.

    2009-01-01

    OBJECTIVES: The heat shock proteins 60 and 70 (HSP60, HSP70) play an important role in cytoprotection. Under stress conditions they are released into the circulation and elicit an immune response. Anti-HSP60 and anti-HSP70 antibody levels have been associated with cardiovascular disease. Type 1......-control study from the EURODIAB Study of 531 type 1 diabetic patients was performed. SUBJECTS: Cases (n = 363) were defined as those with one or more complications of diabetes; control subjects (n = 168) were all those with no evidence of any complication. We measured anti-HSP60 and anti-HSP70 antibody levels...... quartiles were associated with a 47% reduced odds ratio of micro/macrovascular complications, independently of conventional risk factors, markers of inflammation and endothelial dysfunction [odds ratio (OR) = 0.53, 95% confidence intervals (CI): 0.28-1.02]. CONCLUSIONS: In this large cohort of type 1...

  11. Endurance training alters YKL40, PERM1, and HSP70 skeletal muscle protein contents in men with type 2 diabetes mellitus.

    Science.gov (United States)

    Brinkmann, Christian; Kuckertz, Anika; Schiffer, Thorsten; Bloch, Wilhelm; Predel, Hans-Georg; Brixius, Klara

    2018-05-21

    The fight against type 2 diabetes mellitus (T2DM) is tremendously challenging. This pilot study investigates whether endurance training (3 times per week for 3 months, moderate intensity) can change the skeletal muscle protein contents of chitinase-3-like protein-1 (YKL40), peroxisome proliferator-activated receptor y coactivator-1 and estrogen-related receptor-induced regulator in muscle-1 (PERM1) and heat-shock protein-70 (HSP70), which have been discussed as novel therapeutically relevant targets. Muscle biopsies were obtained from overweight/obese men with T2DM (n = 7, years = 63 ± 9) at T1 (6 weeks pre-training), T2 (1 week pre-training) and T3 (3 to 4 days post-training). The protein levels of YKL40, PERM1, and HSP70 were determined by immunohistochemistry. YKL40, PERM1, and HSP70 were significantly upregulated following endurance training (T2-T3: +103%, +61%, +89%, p = 0.012, p = 0.010, p = 0.028). There was a fiber type-specific distribution of HSP70 with increased protein contents in type I fibers. A significant change in the fiber type distribution with an increase in type I fibers and a decrease in type II fibers was observed post-training. There were no significant differences for YKL40, PERM1, HSP70, or the fiber type distribution between T1 and T2. The training-induced upregulation of YKL40, PERM1, and HSP70 could help manage the diabetic disease and reduce its complications.

  12. Genetic Diversity and Phylogenetic Analysis of the Iranian Leishmania Parasites Based on HSP70 Gene PCR-RFLP and Sequence Analysis.

    Science.gov (United States)

    Nemati, Sara; Fazaeli, Asghar; Hajjaran, Homa; Khamesipour, Ali; Anbaran, Mohsen Falahati; Bozorgomid, Arezoo; Zarei, Fatah

    2017-08-01

    Despite the broad distribution of leishmaniasis among Iranians and animals across the country, little is known about the genetic characteristics of the causative agents. Applying both HSP70 PCR-RFLP and sequence analyses, this study aimed to evaluate the genetic diversity and phylogenetic relationships among Leishmania spp. isolated from Iranian endemic foci and available reference strains. A total of 36 Leishmania isolates from almost all districts across the country were genetically analyzed for the HSP70 gene using both PCR-RFLP and sequence analysis. The original HSP70 gene sequences were aligned along with homologous Leishmania sequences retrieved from NCBI, and subjected to the phylogenetic analysis. Basic parameters of genetic diversity were also estimated. The HSP70 PCR-RFLP presented 3 different electrophoretic patterns, with no further intraspecific variation, corresponding to 3 Leishmania species available in the country, L. tropica, L. major, and L. infantum. Phylogenetic analyses presented 5 major clades, corresponding to 5 species complexes. Iranian lineages, including L. major, L. tropica, and L. infantum, were distributed among 3 complexes L. major, L. tropica, and L. donovani. However, within the L. major and L. donovani species complexes, the HSP70 phylogeny was not able to distinguish clearly between the L. major and L. turanica isolates, and between the L. infantum, L. donovani, and L. chagasi isolates, respectively. Our results indicated that both HSP70 PCR-RFLP and sequence analyses are medically applicable tools for identification of Leishmania species in Iranian patients. However, the reduced genetic diversity of the target gene makes it inevitable that its phylogeny only resolves the major groups, namely, the species complexes.

  13. Food odor, visual danger stimulus, and retrieval of an aversive memory trigger heat shock protein HSP70 expression in the olfactory lobe of the crab Chasmagnathus granulatus.

    Science.gov (United States)

    Frenkel, L; Dimant, B; Suárez, L D; Portiansky, E L; Delorenzi, A

    2012-01-10

    Although some of the neuronal substrates that support memory process have been shown in optic ganglia, the brain areas activated by memory process are still unknown in crustaceans. Heat shock proteins (HSPs) are synthesized in the CNS not only in response to traumas but also after changes in metabolic activity triggered by the processing of different types of sensory information. Indeed, the expression of citosolic/nuclear forms of HSP70 (HSC/HSP70) has been repeatedly used as a marker for increases in neural metabolic activity in several processes, including psychophysiological stress, fear conditioning, and spatial learning in vertebrates. Previously, we have shown that, in the crab Chasmagnathus, two different environmental challenges, water deprivation and heat shock, trigger a rise in the number of glomeruli of the olfactory lobes (OLs) expressing HSC/HSP70. In this study, we initially performed a morphometric analysis and identified a total of 154 glomeruli in each OL of Chasmagnathus. Here, we found that crabs exposed to food odor stimuli also showed a significant rise in the number of olfactory glomeruli expressing HSC/HSP70. In the crab Chasmagnathus, a powerful memory paradigm based on a change in its defensive strategy against a visual danger stimulus (VDS) has been extensively studied. Remarkably, the iterative presentation of a VDS caused an increase as well. This increase was triggered in animals visually stimulated using protocols that either build up a long-term memory or generate only short-term habituation. Besides, memory reactivation was sufficient to trigger the increase in HSC/HSP70 expression in the OL. Present and previous results strongly suggest that, directly or indirectly, an increase in arousal is a sufficient condition to bring about an increase in HSC/HSP70 expression in the OL of Chasmagnathus. Copyright © 2011 IBRO. Published by Elsevier Ltd. All rights reserved.

  14. Calpain 3 and CaMKIIβ signaling are required to induce HSP70 necessary for adaptive muscle growth after atrophy

    Science.gov (United States)

    Kramerova, Irina; Torres, Jorge A; Eskin, Ascia; Nelson, Stanley F; Spencer, Melissa J

    2018-01-01

    Abstract Mutations in CAPN3 cause autosomal recessive limb girdle muscular dystrophy 2A. Calpain 3 (CAPN3) is a calcium dependent protease residing in the myofibrillar, cytosolic and triad fractions of skeletal muscle. At the triad, it colocalizes with calcium calmodulin kinase IIβ (CaMKIIβ). CAPN3 knock out mice (C3KO) show reduced triad integrity and blunted CaMKIIβ signaling, which correlates with impaired transcriptional activation of myofibrillar and oxidative metabolism genes in response to running exercise. These data suggest a role for CAPN3 and CaMKIIβ in gene regulation that takes place during adaptation to endurance exercise. To assess whether CAPN3- CaMKIIβ signaling influences skeletal muscle remodeling in other contexts, we subjected C3KO and wild type mice to hindlimb unloading and reloading and assessed CaMKIIβ signaling and gene expression by RNA-sequencing. After induced atrophy followed by 4 days of reloading, both CaMKIIβ activation and expression of inflammatory and cellular stress genes were increased. C3KO muscles failed to activate CaMKIIβ signaling, did not activate the same pattern of gene expression and demonstrated impaired growth at 4 days of reloading. Moreover, C3KO muscles failed to activate inducible HSP70, which was previously shown to be indispensible for the inflammatory response needed to promote muscle recovery. Likewise, C3KO showed diminished immune cell infiltration and decreased expression of pro-myogenic genes. These data support a role for CaMKIIβ signaling in induction of HSP70 and promotion of the inflammatory response during muscle growth and remodeling that occurs after atrophy, suggesting that CaMKIIβ regulates remodeling in multiple contexts: endurance exercise and growth after atrophy. PMID:29528394

  15. Inducible Hsp70 in the Regulation of Cancer Cell Survival: Analysis of Chaperone Induction, Expression and Activity

    Energy Technology Data Exchange (ETDEWEB)

    Zorzi, Elisa [OncoHematology Clinic of Pediatrics, University-Hospital of Padova, 35100 Padova (Italy); Bonvini, Paolo, E-mail: paolo.bonvini@unipd.it [OncoHematology Clinic of Pediatrics, University-Hospital of Padova, 35100 Padova (Italy); Fondazione Città della Speranza, 36030 Monte di Malo, Vicenza (Italy)

    2011-10-21

    Understanding the mechanisms that control stress is central to realize how cells respond to environmental and physiological insults. All the more important is to reveal how tumour cells withstand their harsher growth conditions and cope with drug-induced apoptosis, since resistance to chemotherapy is the foremost complication when curing cancer. Intensive research on tumour biology over the past number of years has provided significant insights into the molecular events that occur during oncogenesis, and resistance to anti-cancer drugs has been shown to often rely on stress response and expression of inducible heat shock proteins (HSPs). However, with respect to the mechanisms guarding cancer cells against proteotoxic stresses and the modulatory effects that allow their survival, much remains to be defined. Heat shock proteins are molecules responsible for folding newly synthesized polypeptides under physiological conditions and misfolded proteins under stress, but their role in maintaining the transformed phenotype often goes beyond their conventional chaperone activity. Expression of inducible HSPs is known to correlate with limited sensitivity to apoptosis induced by diverse cytotoxic agents and dismal prognosis of several tumour types, however whether cancer cells survive because of the constitutive expression of heat shock proteins or the ability to induce them when adapting to the hostile microenvironment remains to be elucidated. Clear is that tumours appear nowadays more “addicted” to heat shock proteins than previously envisaged, and targeting HSPs represents a powerful approach and a future challenge for sensitizing tumours to therapy. This review will focus on the anti-apoptotic role of heat shock 70kDa protein (Hsp70), and how regulatory factors that control inducible Hsp70 synthesis, expression and activity may be relevant for response to stress and survival of cancer cells.

  16. Inducible Hsp70 in the Regulation of Cancer Cell Survival: Analysis of Chaperone Induction, Expression and Activity

    Science.gov (United States)

    Zorzi, Elisa; Bonvini, Paolo

    2011-01-01

    Understanding the mechanisms that control stress is central to realize how cells respond to environmental and physiological insults. All the more important is to reveal how tumour cells withstand their harsher growth conditions and cope with drug-induced apoptosis, since resistance to chemotherapy is the foremost complication when curing cancer. Intensive research on tumour biology over the past number of years has provided significant insights into the molecular events that occur during oncogenesis, and resistance to anti-cancer drugs has been shown to often rely on stress response and expression of inducible heat shock proteins (HSPs). However, with respect to the mechanisms guarding cancer cells against proteotoxic stresses and the modulatory effects that allow their survival, much remains to be defined. Heat shock proteins are molecules responsible for folding newly synthesized polypeptides under physiological conditions and misfolded proteins under stress, but their role in maintaining the transformed phenotype often goes beyond their conventional chaperone activity. Expression of inducible HSPs is known to correlate with limited sensitivity to apoptosis induced by diverse cytotoxic agents and dismal prognosis of several tumour types, however whether cancer cells survive because of the constitutive expression of heat shock proteins or the ability to induce them when adapting to the hostile microenvironment remains to be elucidated. Clear is that tumours appear nowadays more “addicted” to heat shock proteins than previously envisaged, and targeting HSPs represents a powerful approach and a future challenge for sensitizing tumours to therapy. This review will focus on the anti-apoptotic role of heat shock 70kDa protein (Hsp70), and how regulatory factors that control inducible Hsp70 synthesis, expression and activity may be relevant for response to stress and survival of cancer cells. PMID:24213118

  17. Mercury induced oxidative stress, DNA damage, and activation of antioxidative system and Hsp70 induction in duckweed (Lemna minor).

    Science.gov (United States)

    Zhang, Tingting; Lu, Qianqian; Su, Chunlei; Yang, Yaru; Hu, Dan; Xu, Qinsong

    2017-09-01

    Mercury uptake and its effects on physiology, biochemistry and genomic stability were investigated in Lemna minor after 2 and 6d of exposure to 0-30μM Hg. The accumulation of Hg increased in a concentration- and duration-dependent manner, and was positively correlated with the leaf damage. Oxidative stress after Hg exposure was evidenced in L. minor by a significant decrease in photosynthetic pigments, an increase in malondialdehyde and lipoxygenase activities (total enzyme activity and isoenzymes activity). Fronds of L. minor exposed to Hg showed an induction of peroxidase, catalase, and ascorbate peroxidase activities (total enzyme activity and some isoenzymes activities). Exposure of L. minor to Hg reduced the activity (total enzyme activity and some isoenzymes activities) of glutathione reductase, and superoxide dismutase. Exposure to Hg produced a transient increase in the content of glutathione and ascorbic acid. The content of dehydroascorbate and oxidized glutathione in L. minor were high during the entire exposure period. Exposure of L. minor to Hg also caused the accumulation of proline and soluble sugars. The amplification of new bands and the absence of normal DNA amplicons in treated plants in the random amplified polymorphic DNA (RAPD) profile indicated that genomic template stability (GTS) was affected by Hg treatment. The accumulation of Hsp70 indicated the occurrence of a heat shock response at all Hg concentrations. These results suggest that L. minor plants were able to cope with Hg toxicity through the activation of various mechanisms involving enzymatic and non-enzymatic antioxidants, up-regulation of proline, and induction of Hsp70. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. Characterization of CaHsp70-1, a Pepper Heat-Shock Protein Gene in Response to Heat Stress and Some Regulation Exogenous Substances in Capsicum annuum L.

    Science.gov (United States)

    Guo, Meng; Zhai, Yu-Fei; Lu, Jin-Ping; Chai, Lin; Chai, Wei-Guo; Gong, Zhen-Hui; Lu, Ming-Hui

    2014-01-01

    Pepper (Capsicum annuum L.) is sensitive to heat stress (HS). Heat shock proteins 70 (Hsp70s) play a crucial role in protecting plant cells against HS and control varies characters in different plants. However, CaHsp70-1 gene was not well characterized in pepper. In this study, CaHsp70-1 was cloned from the pepper thermotolerant line R9, which encoded a protein of 652 amino acids, with a molecular weight of 71.54 kDa and an isoelectric point of 5.20. CaHsp70-1 belongs to the cytosolic Hsp70 subgroup, and best matched with tomato SlHsp70. CaHsp70-1 was highly induced in root, stem, leaf and flower in R9 with HS treatment (40 °C for 2 h). In both thermosensitive line B6 and thermotolerant line R9, CaHsp70-1 significantly increased after 0.5 h of HS (40 °C), and maintained in a higher level after 4 h HS. The expression of CaHsp70-1 induced by CaCl2, H2O2 and putrescine (Put) under HS were difference between B6 and R9 lines. The different expression patterns may be related to the differences in promoters of CaHsp70-1 from the two lines. These results suggest that CaHsp70-1 as a member of cytosolic Hsp70 subgroup, may be involved in HS defense response via a signal transduction pathway contained Ca2+, H2O2 and Put. PMID:25356507

  19. Use of a Chimeric Hsp70 to Enhance the Quality of Recombinant Plasmodium falciparum S-Adenosylmethionine Decarboxylase Protein Produced in Escherichia coli

    Science.gov (United States)

    Makhoba, Xolani Henry; Burger, Adélle; Coertzen, Dina; Zininga, Tawanda; Birkholtz, Lyn-Marie; Shonhai, Addmore

    2016-01-01

    S-adenosylmethionine decarboxylase (PfAdoMetDC) from Plasmodium falciparum is a prospective antimalarial drug target. The production of recombinant PfAdoMetDC for biochemical validation as a drug target is important. The production of PfAdoMetDC in Escherichia coli has been reported to result in unsatisfactory yields and poor quality product. The co-expression of recombinant proteins with molecular chaperones has been proposed as one way to improve the production of the former in E. coli. E. coli heat shock proteins DnaK, GroEL-GroES and DnaJ have previously been used to enhance production of some recombinant proteins. However, the outcomes were inconsistent. An Hsp70 chimeric protein, KPf, which is made up of the ATPase domain of E. coli DnaK and the substrate binding domain of P. falciparum Hsp70 (PfHsp70) has been previously shown to exhibit chaperone function when it was expressed in E. coli cells whose resident Hsp70 (DnaK) function was impaired. We proposed that because of its domain constitution, KPf would most likely be recognised by E. coli Hsp70 co-chaperones. Furthermore, because it possesses a substrate binding domain of plasmodial origin, KPf would be primed to recognise recombinant PfAdoMetDC expressed in E. coli. First, using site-directed mutagenesis, followed by complementation assays, we established that KPf with a mutation in the hydrophobic residue located in its substrate binding cavity was functionally compromised. We further co-expressed PfAdoMetDC with KPf, PfHsp70 and DnaK in E. coli cells either in the absence or presence of over-expressed GroEL-GroES chaperonin. The folded and functional status of the produced PfAdoMetDC was assessed using limited proteolysis and enzyme assays. PfAdoMetDC co-expressed with KPf and PfHsp70 exhibited improved activity compared to protein co-expressed with over-expressed DnaK. Our findings suggest that chimeric KPf may be an ideal Hsp70 co-expression partner for the production of recombinant plasmodial

  20. Plasmodium falciparum Hop (PfHop Interacts with the Hsp70 Chaperone in a Nucleotide-Dependent Fashion and Exhibits Ligand Selectivity.

    Directory of Open Access Journals (Sweden)

    Tawanda Zininga

    Full Text Available Heat shock proteins (Hsps play an important role in the development and pathogenicity of malaria parasites. One of the most prominent functions of Hsps is to facilitate the folding of other proteins. Hsps are thought to play a crucial role when malaria parasites invade their host cells and during their subsequent development in hepatocytes and red blood cells. It is thought that Hsps maintain proteostasis under the unfavourable conditions that malaria parasites encounter in the host environment. Although heat shock protein 70 (Hsp70 is capable of independent folding of some proteins, its functional cooperation with heat shock protein 90 (Hsp90 facilitates folding of some proteins such as kinases and steroid hormone receptors into their fully functional forms. The cooperation of Hsp70 and Hsp90 occurs through an adaptor protein called Hsp70-Hsp90 organising protein (Hop. We previously characterised the Hop protein from Plasmodium falciparum (PfHop. We observed that the protein co-localised with the cytosol-localised chaperones, PfHsp70-1 and PfHsp90 at the blood stages of the malaria parasite. In the current study, we demonstrated that PfHop is a stress-inducible protein. We further explored the direct interaction between PfHop and PfHsp70-1 using far Western and surface plasmon resonance (SPR analyses. The interaction of the two proteins was further validated by co-immunoprecipitation studies. We observed that PfHop and PfHsp70-1 associate in the absence and presence of either ATP or ADP. However, ADP appears to promote the association of the two proteins better than ATP. In addition, we investigated the specific interaction between PfHop TPR subdomains and PfHsp70-1/ PfHsp90, using a split-GFP approach. This method allowed us to observe that TPR1 and TPR2B subdomains of PfHop bind preferentially to the C-terminus of PfHsp70-1 compared to PfHsp90. Conversely, the TPR2A motif preferentially interacted with the C-terminus of PfHsp90. Finally, we

  1. HDJC9, a novel human type C DnaJ/HSP40 member interacts with and cochaperones HSP70 through the J domain

    International Nuclear Information System (INIS)

    Han Chaofeng; Chen Taoyong; Li Nan; Yang Mingjin; Wan Tao; Cao Xuetao

    2007-01-01

    HSP40s are a subfamily of heat shock proteins (HSPs) and play important roles in regulation of cell proliferation, survival and apoptosis by serving as chaperones for HSP70s. Up to date hundreds of HSP40 proteins derived from various species ranging from Escherichia coli to homo sapiens have been identified. Here we report the cloning and characterization of a novel human type C DnaJ homologue, HDJC9, containing a typical N-terminal J domain. HDJC9 is upregulated at both mRNA and protein levels upon various stress and mitogenic stimulations. HDJC9 is mainly localized in cell nuclei under normal culture conditions while it is transported into cytoplasm and plasma membrane upon heat shock stress through a non-classical and lipid-dependent pathway. HDJC9 can interact with HSP70s and activate the ATPase activity of HSP70s, both of which are dependent on the J domain. Our data suggest that HDJC9 is a novel cochaperone for HSP70s

  2. Stress Proteins (hsp70, hsp60) Induced in Isopods and Nematodes by Field Exposure to Metals in a Gradient near Avonmouth, UK

    NARCIS (Netherlands)

    Arts, M.S.J.; Schill, R.O.; Knigge, T.; Eckwert, H.; Kammenga, J.E.; Köhler, H.R.

    2004-01-01

    Heat shock proteins (hsps) are potential biomarkers for monitoring environmental pollution. In this study, the use of hsps as biomarkers in field bioassays was evaluated in terrestrial invertebrates exposed to a metal gradient near Avonmouth, UK. We investigated the hsp70 response in resident and

  3. Effect of vibrational stress and spaceflight on regulation of heat shock proteins hsp70 and hsp27 in human lymphocytes (Jurkat)

    Science.gov (United States)

    Cubano, L. A.; Lewis, M. L.

    2001-01-01

    Heat shock protein levels are increased in cells as a result of exposure to stress. To determine whether heat shock protein regulation could be used to evaluate stress in cells during spaceflight, the response of Jurkat cells to spaceflight and simulated space shuttle launch vibration was investigated by evaluating hsp70 and hsp27 gene expression. Gene expression was assessed by reverse transcription-polymerase chain reaction using mRNA extracted from vibrated, nonvibrated, space-flown, and ground control cells. Results indicate that mechanical stresses of vibration and low gravity do not up-regulate the mRNA for hsp70, although the gene encoding hsp27 is up-regulated by spaceflight but not by vibration. In ground controls, the mRNA for hsp70 and hsp27 increased with time in culture. We conclude that hsp70 gene expression is a useful indicator of stress related to culture density but is not an indicator of the stresses of launch vibration or microgravity. Up-regulation of hsp27 gene expression in microgravity is a new finding.

  4. A DOUBLE KNOCKOUT; A NOVEL APPROACH TO UNDERSTANDING STRESS-INDUCIBLE 70 KDA HEAT SHOCK PROTEINS (HSP70S) ON DEVELOPMENT AND REPRODUCTION

    Science.gov (United States)

    Heat and chemical toxicants which disrupt spermatogenesis and cause male infertility are thought to induce the expression of Hsp70-1 and 70-3, the major inducible heat shock proteins of the 70kDa family. Previous studies from several laboratories including our own have characteri...

  5. HSP70 gene expression in Mytilus galloprovincialis hemocytes is triggered by moderate heat shock and Vibrio anguillarum, but not by V. splendidus or Micrococcus lysodeikticus.

    Science.gov (United States)

    Cellura, Cinzia; Toubiana, Mylène; Parrinello, Nicolo; Roch, Philippe

    2006-01-01

    Complete sequence of HSP70 cDNA from the mussel, Mytilus galloprovincialis was established before quantifying its expression following moderate heat shock or injection of heat-killed bacteria. HSP70 cDNA is comprised of 2378 bp including one ORF of 654 aa, with a predicted 70 bp 5'-UTR and a 343 bp 3'-UTR (GenBank, 18 Jan 05, AY861684). Alignment identity ranged from 89% for Crassostrea ariakensis to 72% for C. virginica. Curiously, HSP70 gene and cDNA sequences from M. galloprovincialis, deposited later (03 and 27 May), show only 73% identity with the present sequence. Meanwhile, characteristic motifs of the HSP70 family were located in conserved positions. Expression of HSP70 gene was quantified on circulating hemocyte mRNA using Q-PCR after RT using random hexaprimers. Housekeeping gene was 28S rRNA. Four stresses were applied: heat shock that consisted of immersing mussels for 90 min at 30 degrees C and returning them to 20 degrees C sea water, one injection of heat-killed Gram-negative bacteria, Vibrio splendidus LGP32, one injection of heat-killed Gram-negative bacteria Vibrio anguillarum, one injection of heat-killed Gram-positive bacteria Micrococcus lysodeikticus. We found no significant modification of 28S rRNA gene expression. Significant increase of 5.2 +/- 0.4 fold the ratio HSP70/28S rRNA was observed 6 h after heat shock and was maximum at 15 h (6.1 +/- 1.1), and still significant after 24 h (1.7 +/- 0.03). Similarly, injecting V. anguillarum resulted in a significant increase of 2.7 +/- 0.1 after 12 h. Expression was maximum after 48 h (5.2 +/- 0.05) and returned to baseline after 72 h. In contrast, injecting V. splendidus or M. lysodeikticus failed to significantly modulate HSP70 gene expression at least during the first 3 days post-injection. Consequently, mussel hemocytes appeared to discriminate between pathogenic and non-pathogenic Vibrios, as well as between Gram-negative and Gram-positive bacteria.

  6. The Type II Hsp40 Sis1 cooperates with Hsp70 and the E3 ligase Ubr1 to promote degradation of terminally misfolded cytosolic protein.

    Directory of Open Access Journals (Sweden)

    Daniel W Summers

    Full Text Available Mechanisms for cooperation between the cytosolic Hsp70 system and the ubiquitin proteasome system during protein triage are not clear. Herein, we identify new mechanisms for selection of misfolded cytosolic proteins for degradation via defining functional interactions between specific cytosolic Hsp70/Hsp40 pairs and quality control ubiquitin ligases. These studies revolved around the use of S. cerevisiae to elucidate the degradation pathway of a terminally misfolded reporter protein, short-lived GFP (slGFP. The Type I Hsp40 Ydj1 acts with Hsp70 to suppress slGFP aggregation. In contrast, the Type II Hsp40 Sis1 is required for proteasomal degradation of slGFP. Sis1 and Hsp70 operate sequentially with the quality control E3 ubiquitin ligase Ubr1 to target slGFP for degradation. Compromise of Sis1 or Ubr1 function leads slGFP to accumulate in a Triton X-100-soluble state with slGFP degradation intermediates being concentrated into perinuclear and peripheral puncta. Interestingly, when Sis1 activity is low the slGFP that is concentrated into puncta can be liberated from puncta and subsequently degraded. Conversely, in the absence of Ubr1, slGFP and the puncta that contain slGFP are relatively stable. Ubr1 mediates proteasomal degradation of slGFP that is released from cytosolic protein handling centers. Pathways for proteasomal degradation of misfolded cytosolic proteins involve functional interplay between Type II Hsp40/Hsp70 chaperone pairs, PQC E3 ligases, and storage depots for misfolded proteins.

  7. Influence of the cestode Ligula intestinalis and the acanthocephalan Polymorphus minutus on levels of heat shock proteins (HSP70) and metallothioneins in their fish and crustacean intermediate hosts

    International Nuclear Information System (INIS)

    Frank, Sabrina N.; Godehardt, Saskia; Nachev, Milen; Trubiroha, Achim; Kloas, Werner; Sures, Bernd

    2013-01-01

    It is a common method to analyse physiological mechanisms of organisms – commonly referred to as biomarkers – to indicate the presence of environmental pollutants. However, as biomarkers respond to a wide range of stressors we want to direct the attention on natural stressors, i.e. on parasites. After two years maintenance under controlled conditions, roach (Rutilus rutilus) revealed no influence on levels of metallothionein by the parasite Ligula intestinalis. The same was found for Gammarus fossarum infected with Polymorphus minutus. However, the heat shock protein (HSP70) response was affected in both host-parasite systems. While the infection of roach resulted in reduced levels of HSP70 compared to uninfected roach, the infection in G. fossarum led to higher levels of HSP70. We also analysed the effect of a 14 days Cd exposure (4 μg/L) on the uninfected and infected gammarids. The exposure resulted in induced levels for both, metallothionein and HSP70 whereas the combination of stressors, parasite and exposure, revealed a decrease for levels of HSP70 in comparison to the metal exposure only. Accordingly, parasites as natural parts of aquatic ecosystems have to be considered in ecotoxicological research. -- Highlights: •We show how parasites and pollutant affect biomarkers. •Metallothioneins were not influenced by parasites. •Heat shock proteins are modulated by parasites. •Biomarker levels of organisms are dependent on infection status. •Infection with parasites has to be considered in ecotoxicology. -- Parasites are capable of affecting host physiology and therefore modulate biomarker responses

  8. Sequence analysis of the 3’-untranslated region of HSP70 (type I genes in the genus Leishmania: its usefulness as a molecular marker for species identification

    Directory of Open Access Journals (Sweden)

    Requena Jose M

    2012-04-01

    Full Text Available Abstract Background The Leishmaniases are a group of clinically diverse diseases caused by parasites of the genus Leishmania. To distinguish between species is crucial for correct diagnosis and prognosis as well as for treatment decisions. Recently, sequencing of the HSP70 coding region has been applied in phylogenetic studies and for identifying of Leishmania species with excellent results. Methods In the present study, we analyzed the 3’-untranslated region (UTR of Leishmania HSP70-type I gene from 24 strains representing eleven Leishmania species in the belief that this non-coding region would have a better discriminatory capacity for species typing than coding regions. Results It was observed that there was a remarkable degree of sequence conservation in this region, even between species of the subgenus Leishmania and Viannia. In addition, the presence of many microsatellites was a common feature of the 3´-UTR of HSP70-I genes in the Leishmania genus. Finally, we constructed dendrograms based on global sequence alignments of the analyzed Leishmania species and strains, the results indicated that this particular region of HSP70 genes might be useful for species (or species complex typing, improving for particular species the discrimination capacity of phylogenetic trees based on HSP70 coding sequences. Given the large size variation of the analyzed region between the Leishmania and Viannia subgenera, direct visualization of the PCR amplification product would allow discrimination between subgenera, and a HaeIII-PCR-RFLP analysis might be used for differentiating some species within each subgenera. Conclusions Sequence and phylogenetic analyses indicated that this region, which is readily amplified using a single pair of primers from both Old and New World Leishmania species, might be useful as a molecular marker for species discrimination.

  9. In-vivo optical imaging of hsp70 expression to assess collateral tissue damage associated with infrared laser ablation of skin

    Science.gov (United States)

    Wilmink, Gerald J.; Opalenik, Susan R.; Beckham, Joshua T.; Mackanos, Mark A.; Nanney, Lillian B.; Contag, Christopher H.; Davidson, Jeffrey M.; Jansen, E. Duco

    2013-01-01

    Laser surgical ablation is achieved by selecting laser parameters that remove confined volumes of target tissue and cause minimal collateral damage. Previous studies have measured the effects of wavelength on ablation, but neglected to measure the cellular impact of ablation on cells outside the lethal zone. In this study, we use optical imaging in addition to conventional assessment techniques to evaluate lethal and sublethal collateral damage after ablative surgery with a free-electron laser (FEL). Heat shock protein (HSP) expression is used as a sensitive quantitative marker of sublethal damage in a transgenic mouse strain, with the hsp70 promoter driving luciferase and green fluorescent protein (GFP) expression (hsp70A1-L2G). To examine the wavelength dependence in the mid-IR, laser surgery is conducted on the hsp70A1-L2G mouse using wavelengths targeting water (OH stretch mode, 2.94 μm), protein (amide-II band, 6.45 μm), and both water and protein (amide-I band, 6.10 μm). For all wavelengths tested, the magnitude of hsp70 expression is dose-dependent and maximal 5 to 12 h after surgery. Tissues treated at 6.45 μm have approximately 4× higher hsp70 expression than 6.10 μm. Histology shows that under comparable fluences, tissue injury at the 2.94-μm wavelength was 2× and 3× deeper than 6.45 and 6.10 μm, respectively. The 6.10-μm wavelength generates the least amount of epidermal hyperplasia. Taken together, this data suggests that the 6.10-μm wavelength is a superior wavelength for laser ablation of skin. PMID:19021444

  10. Interference with the HSF1/HSP70/BAG3 Pathway Primes Glioma Cells to Matrix Detachment and BH3 Mimetic-Induced Apoptosis.

    Science.gov (United States)

    Antonietti, Patrick; Linder, Benedikt; Hehlgans, Stephanie; Mildenberger, Iris C; Burger, Michael C; Fulda, Simone; Steinbach, Joachim P; Gessler, Florian; Rödel, Franz; Mittelbronn, Michel; Kögel, Donat

    2017-01-01

    Malignant gliomas exhibit a high intrinsic resistance against stimuli triggering apoptotic cell death. HSF1 acts as transcription factor upstream of HSP70 and the HSP70 co-chaperone BAG3 that is overexpressed in glioblastoma. To specifically target this resistance mechanism, we applied the selective HSF1 inhibitor KRIBB11 and the HSP70/BAG3 interaction inhibitor YM-1 in combination with the pan-Bcl-2 inhibitor AT-101. Here, we demonstrate that lentiviral BAG3 silencing significantly enhances AT-101-induced cell death and reactivates effector caspase-mediated apoptosis in U251 glioma cells with high BAG3 expression, whereas these sensitizing effects were less pronounced in U343 cells expressing lower BAG3 levels. KRIBB11 decreased protein levels of HSP70, BAG3, and the antiapoptotic Bcl-2 protein Mcl-1, and both KRIBB11 and YM-1 elicited significantly increased mitochondrial dysfunction, effector caspase activity, and apoptotic cell death after combined treatment with AT-101 and ABT-737. Depletion of BAG3 also led to a pronounced loss of cell-matrix adhesion, FAK phosphorylation, and in vivo tumor growth in an orthotopic mouse glioma model. Furthermore, it reduced the plating efficiency of U251 cells in three-dimensional clonogenic assays and limited clonogenic survival after short-term treatment with AT-101. Collectively, our data suggest that the HSF1/HSP70/BAG3 pathway plays a pivotal role for overexpression of prosurvival Bcl-2 proteins and cell death resistance of glioma. They also support the hypothesis that interference with BAG3 function is an effective novel approach to prime glioma cells to anoikis. Mol Cancer Ther; 16(1); 156-68. ©2016 AACR. ©2016 American Association for Cancer Research.

  11. The expression and correlation of Hsp 70 and Hsp 27 in serous middle ear effusion fluids of pediatric patients-a preliminary study.

    Science.gov (United States)

    Min, Hyun Jin; Choe, Ji Won; Chang, Moon Young; Kim, Kyung Soo; Lee, Sei Young; Mun, Seog-Kyun

    2017-10-01

    Several cytokines and innate immune-associated molecules are present in middle ear effusions, but damage-associated molecular patterns (DAMPs) in middle ear effusion have not been studied. Therefore, we evaluated the role of heat shock proteins (Hsps) in the development of otitis media with effusion (OME). Serous middle ear effusions from 22 pediatric patients who were diagnosed with OME and underwent ventilation tube insertion from June 2015 to March 2017 were evaluated in our study. The levels of Hsp 90, 70, 27, IL-8, and TNF-α in effusion fluids were evaluated by enzyme-linked immunosorbent assays. The associations between the levels of these molecules and the degree of tympanic membrane inflammation were statistically evaluated. Finally, the relationships among these molecules were also evaluated. Hsp 70 and Hsp 27 were detected in all middle ear effusions, but Hsp 90 was detected in only five effusion fluid samples. IL-8 was also detected in all middle ear effusions, but TNF-α was detected in only four effusion fluid samples. When we compared the degree of tympanic membrane inflammation with the levels of Hsp 70, Hsp 27, and IL-8, which were detected in all effusion fluids, we could not find statistical significance. However, Hsp 70, Hsp 27, and IL-8 were significantly associated with each other (p effusions. Furthermore, the levels of Hsp 70 and Hsp 27 were positively correlated with each other, and were also positively associated with the neutrophil chemoattractant, IL-8. Our findings suggested that Hsp 70 and Hsp 27 might be involved in the pathophysiology of pediatric OME. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. RNAi knockdown of Hop (Hsp70/Hsp90 organising protein) decreases invasion via MMP-2 down regulation.

    LENUS (Irish Health Repository)

    Walsh, Naomi

    2011-07-28

    We previously identified Hop as over expressed in invasive pancreatic cancer cell lines and malignant tissues of pancreatic cancer patients, suggesting an important role for Hop in the biology of invasive pancreatic cancer. Hop is a co-chaperone protein that binds to both Hsp70\\/Hsp90. We hypothesised that by targeting Hop, signalling pathways modulating invasion and client protein stabilisation involving Hsp90-dependent complexes may be altered. In this study, we show that Hop knockdown by small interfering (si)RNA reduces the invasion of pancreatic cancer cells, resulting in decreased expression of the downstream target gene, matrix metalloproteinases-2 (MMP-2). Hop in conditioned media co-immunoprecipitates with MMP-2, implicating a possible extracellular function for Hop. Knockdown of Hop expression also reduced expression levels of Hsp90 client proteins, HER2, Bcr-Abl, c-MET and v-Src. Furthermore, Hop is strongly expressed in high grade PanINs compared to lower PanIN grades, displaying differential localisation in invasive ductal pancreatic cancer, indicating that the localisation of Hop is an important factor in pancreatic tumours. Our data suggests that the attenuation of Hop expression inactivates key signal transduction proteins which may decrease the invasiveness of pancreatic cancer cells possibly through the modulation of Hsp90 activity. Therefore, targeting Hop in pancreatic cancer may constitute a viable strategy for targeted cancer therapy.

  13. Development of a colloidal gold immunochromatographic strip based on HSP70 for the rapid detection of Echinococcus granulosus in sheep.

    Science.gov (United States)

    Zhuo, Xunhui; Yu, Yingchao; Chen, Xueqiu; Zhang, Zhuangzhi; Yang, Yi; Du, Aifang

    2017-06-15

    Echinococcus granulosus is the causative pathogen of cystic echinococcosis, a serious disease endangering human and animal health. In this study, an immunochromatographic strip was developed based on the recombinant protein Heat shock protein 70 (HSP70) for the serological detection of E. granulosus. The protocol completes within 20min requiring no specialized equipment or chemical reagents, while specificity tests confirmed no cross-reactivity with positive serum of Fasciola hepatica, Haemonchus contortus, Peste des petits ruminants virus (PPRV) and Foot-and-mouth disease virus (FMDV). The strips remained stable after storage at 4°C for up to 8 months. Both immunochromatographic strip and ELISA tests were applied to detect E. granulosus antibody in a total of 728 serum samples obtained from slaughter houses in Zhejiang Province. Our data revealed positive rates of 2.61 and 1.65% by immunochromatographic strip and ELISA methods, respectively. The immunochromatographic strip test developed in this study provides a simple, specific and rapid method of E. granulosus antibody detection and infected sheep monitoring. Copyright © 2017. Published by Elsevier B.V.

  14. Cry1Ab treatment has no effects on viability of cultured porcine intestinal cells, but triggers Hsp70 expression.

    Directory of Open Access Journals (Sweden)

    Angelika Bondzio

    Full Text Available In vitro testing can contribute to reduce the risk that the use of genetically modified (GM crops and their proteins show unintended toxic effects. Here we introduce a porcine intestinal cell culture (IPEC-J2 as appropriate in vitro model and tested the possible toxic potential of Cry1Ab protein, commonly expressed in GM-maize. For comprehensive risk assessment we used WST-1 conversion and ATP content as metabolic markers for proliferation, lactate dehydrogenase release as indicator for cells with compromised membrane and transepithelial electrical resistance as parameter indicating membrane barrier function. The results were compared to the effects of valinomycin, a potassium ionophore, known to induce cytotoxic effects in most mammalian cell types. Whereas no toxicity was observed after Cry1Ab treatment, valinomycin induced a decrease in IPEC-J2 viability. This was confirmed by dynamic monitoring of cellular responses. Additionally, two dimensional differential in-gel electrophoresis was performed. Only three proteins were differentially expressed. The functions of these proteins were associated with responses to stress. The up-regulation of heat shock protein Hsp70 was verified by Western blotting as well as by enzyme-linked immunosorbent assay and may be related to a protective function. These findings suggest that the combination of in vitro testing and proteomic analysis may serve as a promising tool for mechanism based safety assessment.

  15. Hsp27, Hsp70 and mismatch repair proteins hMLH1 and hMSH2 expression in peripheral blood lymphocytes from healthy subjects and cancer patients.

    Science.gov (United States)

    Nadin, Silvina Beatriz; Vargas-Roig, Laura M; Drago, Gisela; Ibarra, Jorge; Ciocca, Daniel R

    2007-07-08

    Mismatch repair (MMR) deficiency and higher expression levels of heat shock proteins (Hsps) have been implicated with drug resistance to topoisomerase II poisons (doxorubicin) and to platinum compounds (cisplatin). This study was designed to determine individual influences of doxorubicin and cisplatin treatment on the expression of Hsp27, Hsp70, hMLH1 and hMSH2 proteins and in the DNA damage status in peripheral blood lymphocytes (PBLs). In addition, we studied whether these proteins and the DNA damage correlated with the survival of cancer patients. PBLs from 10 healthy donors and 25 cancer patients (before and after three cycles of chemotherapy) were exposed to in vitro treatments: C (control), HS (heat shock at 42 degrees C), Do or Pt (doxorubicin or cisplatin alone), and HS+Do or HS+Pt (heat shock+doxorubicin or heat shock+cisplatin). PBLs were collected at time 0 (T0: immediately after drug treatment) and after 24h of repair (T24). Hsp27, Hsp70, hMLH1 and hMSH2 were studied by immunocytochemistry and the DNA damage by alkaline comet assay. Immunofluorescence studies and confocal microscopy revealed that hMLH1 and hMSH2 colocalized with Hsp27 and Hsp72 (inducible form of Hsp70). hMLH1 and hMSH2 were significantly induced by Pt and HS+Pt at T24 in cancer patients, but only modestly influenced by Do. Cancer patients presented higher basal expression of total and nuclear Hsp27 and Hsp70 than controls, and these proteins were also increased by HS, Do and HS+Do. The Hsp70 induction by Pt and HS+Pt was noted in cancer patients, especially nuclear Hsp70. In cancer patients, basal DNA damage was slightly higher than in healthy persons; and after Pt and HS+Pt treatments, DNA migration and number of apoptotic cells were higher than controls. Hsps accomplished a cytoprotective function in pre-chemotherapy PBLs (HS before Do or Pt), but not in post-chemotherapy samples. In Pt-treated patients the ratio N/C (nuclear/cytoplasmic) of Hsp27 was related to disease free survival

  16. Systematic Proteomic Identification of the Heat Shock Proteins (Hsp) that Interact with Estrogen Receptor Alpha (ERα) and Biochemical Characterization of the ERα-Hsp70 Interaction.

    Science.gov (United States)

    Dhamad, Ahmed E; Zhou, Zhenqi; Zhou, Jianhong; Du, Yuchun

    2016-01-01

    Heat shock proteins (Hsps) are known to associate with estrogen receptors (ER) and regulate ER-mediated cell proliferation. Historically, the studies in this area have focused on Hsp90. However, some critical aspects of the Hsp-ERα interactions remain unclear. For example, we do not know which Hsps are the major or minor ERα interactants and whether or not different Hsp isoforms associate equally with ERα. In the present study, through a quantitative proteomic method we found that 21 Hsps and 3 Hsp cochaperones were associated with ERα in human 293T cells that were cultured in a medium containing necessary elements for cell proliferation. Four Hsp70s (Hsp70-1, Hsc70, Grp75, and Grp78) were the most abundant Hsps identified to associate with ERα, followed by two Hsp90s (Hsp90α and Hsp90β) and three Hsp110s (Hsp105, HspA4, and HspA4L). Hsp90α was found to be 2-3 times more abundant than Hsp90β in the ERα-containing complexes. Among the reported Hsp cochaperones, we detected prostaglandin E synthase 3 (p23), peptidyl-prolyl cis-trans isomerase FKBP5 (FKBP51), and E3 ubiquitin-protein ligase CHIP (CHIP). Studies with the two most abundant ERα-associated Hsps, Hsp70-1 and Hsc70, using human breast cancer MCF7 cells demonstrate that the two Hsps interacted with ERα in both the cytoplasm and nucleus when the cells were cultured in a medium supplemented with fetal bovine serum and phenol red. Interestingly, the ERα-Hsp70-1/Hsc70 interactions were detected only in the cytoplasm but not in the nucleus under hormone starvation conditions, and stimulation of the starved cells with 17β-estradiol (E2) did not change this. In addition, E2-treatment weakened the ERα-Hsc70 interaction but had no effect on the ERα-Hsp70-1 interaction. Further studies showed that significant portions of Hsp70-1 and Hsc70 were associated with transcriptionally active chromatin and inactive chromatin, and the two Hsps interacted with ERα in both forms of the chromatins in MCF7 cells.

  17. Recovery of ovary size, follicle cell apoptosis, and HSP70 expression in fish exposed to bleached pulp mill effluent

    Energy Technology Data Exchange (ETDEWEB)

    Janz, D. M.; Weber, L. P. [Oklahoma State Univ., Stillwater, OK (United States); McMaster, M. E.; Munkittrrick, K. R. [Environment Canada, Burlington, ON (Canada); Van Der Kraak, G. [Guelph Univ., Dept. of Zoology, ON (Canada)

    2001-03-01

    Apoptosis of granulosa cells that provide hormonal support for the oocyte is the normal mechanism by which atresia ( reduced ovarian size, decreased fecundity, delayed sexual maturation, alterations in plasma sex steroid levels, etc) occurs in mammals, birds and possibly fish. The objective of this study is to determine ovarian cell apoptosis, gonadosomatic index (GSI) and heat shock protein (HSP70) expression during the growth stage of ovarian development in white sucker fish in order to compare samples of fish collected upstream and downstream of a bleached kraft pulp mill in Ontario. Fish for the study were collected in two different years, before and after the pulp mill undertook a number of improvements to eliminate the release of process chemicals. Results showed a 3.4-fold increase in ovarian cell apoptosis in growing white sucker collected four km downstream of the bleached kraft pulp mill in 1996 (before the improvements) compared to fish collected from upstream sources. The elevated ovarian cell apoptosis was associated with significant reduction in gonadosomatic index in fish collected downstream. There were no differences in ovarian cell apoptosis or gonadosomatic index between fish collected upstream and four km downstream of the mill in September 1998 (after the improvements.) Based on the results, it may be concluded that chronic stimulation of ovarian cell apoptosis by certain components of bleached kraft pulp mill effluents represents an important cellular mechanism for reducing the size of ovaries and other related reproductive responses in female fish exposed to these effluents. Although the specific effluent components are not known, the improvements undertaken between 1996 and 1998 resulted in significant enough recovery of these responses to justify the belief in a cause-effect relationship. 32 refs., 1 tab., 2 figs.

  18. The genes coding for the hsp70(dnaK) molecular chaperone machine occur in the moderate thermophilic archaeon Methanosarcina thermophila TM-1

    DEFF Research Database (Denmark)

    Hofman-Bang, H Jacob Peider; Lange, Marianne; Ahring, Birgitte Kiær

    1999-01-01

    The hsp70 (dnaK) locus of the moderate thermophilic archaeon Methanosarcina thermophila TM-1 was cloned, sequenced, and tested in vitro to measure gene induction by heat and ammonia, i.e., stressors pertinent to the biotechnological ecosystem of this methanogen that plays a key role in anaerobic...... thermoautotrophicum Delta H, from another genus, in which trkA is not part of the locus. The proteins encoded in the TM-1 genes are very similar to the S-6 homologs, but considerably less similar to the Delta H proteins. The TM-1 Hsp70(DnaK) protein has the 23-amino acid deletion-by comparison with homologs from Gram...

  19. Genetic variation and recombination of RdRp and HSP 70h genes of Citrus tristeza virus isolates from orange trees showing symptoms of citrus sudden death disease

    Directory of Open Access Journals (Sweden)

    Pappas Georgios J

    2008-01-01

    Full Text Available Abstract Background Citrus sudden death (CSD, a disease that rapidly kills orange trees, is an emerging threat to the Brazilian citrus industry. Although the causal agent of CSD has not been definitively determined, based on the disease's distribution and symptomatology it is suspected that the agent may be a new strain of Citrus tristeza virus (CTV. CTV genetic variation was therefore assessed in two Brazilian orange trees displaying CSD symptoms and a third with more conventional CTV symptoms. Results A total of 286 RNA-dependent-RNA polymerase (RdRp and 284 heat shock protein 70 homolog (HSP70h gene fragments were determined for CTV variants infecting the three trees. It was discovered that, despite differences in symptomatology, the trees were all apparently coinfected with similar populations of divergent CTV variants. While mixed CTV infections are common, the genetic distance between the most divergent population members observed (24.1% for RdRp and 11.0% for HSP70h was far greater than that in previously described mixed infections. Recombinants of five distinct RdRp lineages and three distinct HSP70h lineages were easily detectable but respectively accounted for only 5.9 and 11.9% of the RdRp and HSP70h gene fragments analysed and there was no evidence of an association between particular recombinant mosaics and CSD. Also, comparisons of CTV population structures indicated that the two most similar CTV populations were those of one of the trees with CSD and the tree without CSD. Conclusion We suggest that if CTV is the causal agent of CSD, it is most likely a subtle feature of population structures within mixed infections and not merely the presence (or absence of a single CTV variant within these populations that triggers the disease.

  20. Effects of heavy metals on ultrastructure and Hsp70 induction in Lemna minor L. exposed to water along the Sarno River, Italy.

    Science.gov (United States)

    Basile, A; Sorbo, S; Cardi, M; Lentini, M; Castiglia, D; Cianciullo, P; Conte, B; Loppi, S; Esposito, S

    2015-04-01

    The effects of freshwater pollution in the highly contaminated river Sarno (Campania, Southern Italy) have been evaluated using bags containing the aquatic plant Lemna minor (Lemnacee, Arales), in order to determine morpho-physiological modifications as a response to pollutants. The exposition of Lemna bags for 7 days on three different sites along the river path showed alterations in chloroplasts and vacuoles shape and organization. Moreover, some specimens were exposed in vitro at the same heavy metal (HM) concentrations measured in the polluted sites of the river, and compared with data from the bag experiment; to verify the dose and time dependent effects, samples were exposed to HM in vitro at concentrations ranging from 10(-6) to 10(-4)M up to 7 days. Transmission electron microscopy (TEM) observations on in vitro plants confirmed that ultrastructural alterations affected most of plastids and the shape of different subcellular structures, namely vacuoles; in in vitro stressed specimens, Heat Shock Proteins 70 (Hsp70) levels changed, in dependence of changing levels of HM measured in different sites along the river path. Thus L. minor exhibited a possible correlation between the levels of HM pollution and Hsp70 occurrence; interestingly, the data presented showed that copper specifically increased Hsp70 levels at concentrations detected in polluted river waters, whereas cadmium and lead did not; on the other side, the latter represent highly toxic elements when specimens were exposed to higher levels in vitro. The effects of specific elements in vitro are compared to those observed in bags exposed along the river path; thus results are examined in order to propose L. minor as an organism able to be utilized to monitor heavy metals pollution; the possibility of using Hsp70s as specific markers of HM pollution is discussed. Copyright © 2015 Elsevier Inc. All rights reserved.

  1. Expression of hsp70 and ferritin in embryos of the copepod Acartia tonsa (Dana) during transition between subitaneous and quiescent state

    DEFF Research Database (Denmark)

    Nilsson, Birgitte; Jepsen, Per Meyer; Rewitz, Kim Furbo

    2014-01-01

    Subitaneous eggs of the neritic calanoid copepod Acartia tonsa (Dana) are capable of entering a resting state called quiescence to overcome adverse environmental conditions. Although physiological changes associated with this transition have been described, the molecular mechanisms are thus far...... for ferritin during the recovery phase toward hatching. This suggests that ferritin is a protein needed when embryos of A. tonsa enter quiescence. Both hsp70 and ferritin are required during recovery from quiescent to subitaneous state when embryogenesis continues toward egg hatching....

  2. Ekspresi Human Leukocyte Antigen-G (HLA-G dan Heat-Shock Protein-70 (Hsp-70 pada Pertumbuhan Janin Terhambat

    Directory of Open Access Journals (Sweden)

    Sri Sulistyowati

    2014-03-01

    Full Text Available Intra uterine growth retardation (IUGR is one of the leading causes of higher morbidity and mortality in perinatal. Immune maladaptation affects trophoblast invasion and spiralis arteria remodeling that will cause placental tissue hypoxia. This research aimed to analyze human leukocyte antigen-G (HLA-G and heat-shock protein-70 (Hsp-70 expression on the IUGR trophoblast and normal pregnancy, by applying analytical observational method and cross sectional approach. This research was conducted at the Obstetric and Gynecology Department of Dr. Moewardi Hospital Surakarta from November to December 2011. The total samples were 30, divided into two groups. There were 15 samples trophoblast on IUGR and 15 samples trophoblast from normal pregnancy. All samples were tested for HLA-G and Hsp-70 using immunohistochemistry. The data were analyzed by using t-test. The mean of HLA-G expression on the IUGR groups was 32.42±8.90 and on the normal pregnancy groups was 43.92±14.91 (p=0.016. Heat-shock protein70 expression on the IUGR groups was 2.4355+0.26647 and on the normal pregnancy groups was 1.5920+0.17142 with p=0.008. In conclusion, in IUGR, the HLA-G expression is lower and the Hsp-70 expression is higher than in normal pregnancy.

  3. EFFECT OF STRESS ON THE PERCENT BODY WEIGHT CHANGE AND MRNA EXPRESSION OF IGF-1, SURVIVINE AND HSP-70 GENE IN THE HIERARCHIAL FOLLICLES OF JAPANESE QUAIL

    Directory of Open Access Journals (Sweden)

    N Shit

    2014-12-01

    Full Text Available The present study was carried out to explore the effect of stress on body weight and the mRNA expression of IGF-1, Survivine and HSP-70 gene in the hierarchial follicles of Japanese quail. A total 24 birds (10 weeks were taken and stress was induced by immobilization daily for 2hrs (between 9.00 - 11.00 AM throughout the study (10 days. Four birds were sacrificed on 1, 2, 4, 6, 8 and 10 days of the treatment. Hierarchial follicles (F1, F2 & F3 were aseptically collected to quantify the expression of IGF-1, Survivine and HSP-70 gene using real-time PCR technique. The percent body weight reduction increased and reached highest (21.30% on 10th day. The fold expression of IGF-1 gene was significantly ((P=0.05 down regulated in advance to the time of experiment. However, the fold expression of survivine gene was significantly (P=0.05 up regulated and the intensity was highest (17 fold in F-3 follicle on 4th day of experiment. No significant change in the mRNA expression of HSP-70 gene was evident in this study. From this study it may be concluded that stress brings physio-molecular change through HPA activation, which not only causes tissue regression also modifies the cellular mechanism.

  4. Crystallization and X-ray data analysis of the 10 kDa C-terminal lid subdomain from Caenorhabditis elegans Hsp70

    Energy Technology Data Exchange (ETDEWEB)

    Worrall, Liam; Walkinshaw, Malcolm D., E-mail: m.walkinshaw@ed.ac.uk [School of Biological Sciences, University of Edinburgh, The King’s Buildings, Mayfield Road, Edinburgh EH9 3JR,Scotland (United Kingdom)

    2006-09-01

    Crystals of the C-terminal 10 kDa lid subdomain from the C. elegans chaperone Hsp70 have been obtained that diffract X-rays to ∼3.5 Å and belong to space group I2{sub 1}2{sub 1}2{sub 1}. Analysis of X-ray data and initial heavy-atom phasing reveals 24 monomers in the asymmetric unit related by 432 non-crystallographic symmetry. Hsp70 is an important molecular chaperone involved in the regulation of protein folding. Crystals of the C-terminal 10 kDa helical lid domain (residues 542–640) from a Caenorhabditis elegans Hsp70 homologue have been produced that diffract X-rays to ∼3.4 Å. Crystals belong to space group I2{sub 1}2{sub 1}2{sub 1}, with unit-cell parameters a = b = 197, c = 200 Å. The Matthews coefficient, self-rotation function and Patterson map indicate 24 monomers in the asymmetric unit, showing non-crystallographic 432 symmetry. Molecular-replacement studies using the corresponding domain from rat, the only eukaryotic homologue with a known structure, failed and a mercury derivative was obtained. Preliminary MAD phasing using SHELXD and SHARP for location and refinement of the heavy-atom substructure and SOLOMON for density modification produced interpretable maps with a clear protein–solvent boundary. Further density-modification, model-building and refinement are currently under way.

  5. Effects of salinity fluctuation frequency on the osmolarity, Na+-K+-ATPase activity and HSP70 expression in juvenile chinese shrimp, Fenneropenaeus chinensis

    Science.gov (United States)

    Ding, Sen; Wang, Fang; Sun, Hao; Guo, Biao; Dong, Shuanglin

    2009-03-01

    Experiments were conducted to examine the effects of salinity fluctuation frequency on the osmolarity, Na+-K+-ATPase activity and HSP70 of Chinese shrimp Fenneropenaeus chinensis with initial wet body weight of 1.460 g ± 0.091 g. The salinity in the control group (D0) was 28 throughout the experiment, whereas treatments D2, D4, D6 and D8 were subjected to different salinity fluctuation frequencies of 2, 4, 6 and 8 d, respectively. The salinity in treatments D2, D4, D6 and D8 was kept at 28 for 2, 4, 6 and 8 d, respectively, decreased abruptly to salinity 24, lasted for another 2 d, and then was raised to its initial value 28. This was a complete salinity fluctuation cycle that afterwards repeated itself. After 32 days, the osmolarity in treatments D2, D4, D6 and D8 was significantly lower than that in treatment D0 ( P<0.05). There were significant differences in both muscle and eyestalks HSP70 expression among groups. The HSP70 expressions in muscle and eyestalks in group D4 were 61.4% and 57.0% higher, respectively, than that in the control group D0 ( P<0.05). There were, however, no significant differences in gill or hepatopancreas Na+-K+-ATPase activity between the treatments and the control.

  6. De novo characterisation of the greenlip abalone transcriptome (Haliotis laevigata) with a focus on the heat shock protein 70 (HSP70) family.

    Science.gov (United States)

    Shiel, Brett P; Hall, Nathan E; Cooke, Ira R; Robinson, Nicholas A; Strugnell, Jan M

    2015-02-01

    Abalone (Haliotis) are economically important molluscs for fisheries and aquaculture industries worldwide. Despite this, genomic resources for abalone and molluscs are still limited. Here we present a description and functional annotation of the greenlip abalone (Haliotis laevigata) transcriptome. We present a focused analysis on the heat shock protein 70 (HSP70) family of genes with putative functions affecting temperature stress and immunity. A total of ~38 million paired end Illumina reads were obtained, resulting in a Trinity assembly of 222,172 contigs with minimum length of 200 base pairs and maximum length of 33 kilobases. The 20,702 contigs were annotated with gene descriptions by BLAST. We created a program to maximise the number of functionally annotated genes, and over 10,000 contigs were assigned Gene ontologies (GO terms). By using CateGOrizer, immunity related GO terms for stressors such as heat, hypoxia, oxidative stress and wounding received the highest counts. Twenty-six contigs with homology to the HSP70 family of genes were identified. Ninety-one putative single-nucleotide polymorphisms were observed in the abalone HSP70 contigs. Eleven of these were considered non-synonymous. The annotated transcriptome described in this study will be a useful basis for future work investigating the genetic response of abalone to stress.

  7. Long-Term Overexpression of Hsp70 Does Not Protect against Cardiac Dysfunction and Adverse Remodeling in a MURC Transgenic Mouse Model with Chronic Heart Failure and Atrial Fibrillation.

    Science.gov (United States)

    Bernardo, Bianca C; Sapra, Geeta; Patterson, Natalie L; Cemerlang, Nelly; Kiriazis, Helen; Ueyama, Tomomi; Febbraio, Mark A; McMullen, Julie R

    2015-01-01

    Previous animal studies had shown that increasing heat shock protein 70 (Hsp70) using a transgenic, gene therapy or pharmacological approach provided cardiac protection in models of acute cardiac stress. Furthermore, clinical studies had reported associations between Hsp70 levels and protection against atrial fibrillation (AF). AF is the most common cardiac arrhythmia presenting in cardiology clinics and is associated with increased rates of heart failure and stroke. Improved therapies for AF and heart failure are urgently required. Despite promising observations in animal studies which targeted Hsp70, we recently reported that increasing Hsp70 was unable to attenuate cardiac dysfunction and pathology in a mouse model which develops heart failure and intermittent AF. Given our somewhat unexpected finding and the extensive literature suggesting Hsp70 provides cardiac protection, it was considered important to assess whether Hsp70 could provide protection in another mouse model of heart failure and AF. The aim of the current study was to determine whether increasing Hsp70 could attenuate adverse cardiac remodeling, cardiac dysfunction and episodes of arrhythmia in a mouse model of heart failure and AF due to overexpression of Muscle-Restricted Coiled-Coil (MURC). Cardiac function and pathology were assessed in mice at approximately 12 months of age. We report here, that chronic overexpression of Hsp70 was unable to provide protection against cardiac dysfunction, conduction abnormalities, fibrosis or characteristic molecular markers of the failing heart. In summary, elevated Hsp70 may provide protection in acute cardiac stress settings, but appears insufficient to protect the heart under chronic cardiac disease conditions.

  8. Long-Term Overexpression of Hsp70 Does Not Protect against Cardiac Dysfunction and Adverse Remodeling in a MURC Transgenic Mouse Model with Chronic Heart Failure and Atrial Fibrillation.

    Directory of Open Access Journals (Sweden)

    Bianca C Bernardo

    Full Text Available Previous animal studies had shown that increasing heat shock protein 70 (Hsp70 using a transgenic, gene therapy or pharmacological approach provided cardiac protection in models of acute cardiac stress. Furthermore, clinical studies had reported associations between Hsp70 levels and protection against atrial fibrillation (AF. AF is the most common cardiac arrhythmia presenting in cardiology clinics and is associated with increased rates of heart failure and stroke. Improved therapies for AF and heart failure are urgently required. Despite promising observations in animal studies which targeted Hsp70, we recently reported that increasing Hsp70 was unable to attenuate cardiac dysfunction and pathology in a mouse model which develops heart failure and intermittent AF. Given our somewhat unexpected finding and the extensive literature suggesting Hsp70 provides cardiac protection, it was considered important to assess whether Hsp70 could provide protection in another mouse model of heart failure and AF. The aim of the current study was to determine whether increasing Hsp70 could attenuate adverse cardiac remodeling, cardiac dysfunction and episodes of arrhythmia in a mouse model of heart failure and AF due to overexpression of Muscle-Restricted Coiled-Coil (MURC. Cardiac function and pathology were assessed in mice at approximately 12 months of age. We report here, that chronic overexpression of Hsp70 was unable to provide protection against cardiac dysfunction, conduction abnormalities, fibrosis or characteristic molecular markers of the failing heart. In summary, elevated Hsp70 may provide protection in acute cardiac stress settings, but appears insufficient to protect the heart under chronic cardiac disease conditions.

  9. Induction of heat shock proteins (hsp70) in the zebra mussel (Dreissena polymorpha) following exposure to platinum group metals (platinum, palladium and rhodium): Comparison with lead and cadmium exposures

    Energy Technology Data Exchange (ETDEWEB)

    Singer, Christoph [Zoologisches Institut I-Oekologie, Universitaet Karlsruhe, Geb. 07.01, Kornblumenstrasse 13, D-76131 Karlsruhe (Germany); Zimmermann, Sonja [Zoologisches Institut I-Oekologie, Universitaet Karlsruhe, Geb. 07.01, Kornblumenstrasse 13, D-76131 Karlsruhe (Germany); Sures, Bernd [Zoologisches Institut I-Oekologie, Universitaet Karlsruhe, Geb. 07.01, Kornblumenstrasse 13, D-76131 Karlsruhe (Germany)]. E-mail: dc11@rz.uni-karlsruhe.de

    2005-10-05

    An increasing number of papers concentrate on the availability and uptake of platinum group elements (PGE) by different organisms. These metals are discharged into the environment from different anthropogenic sources, such as automobile catalytic converters, hospitals and other medical institutions. As the effects of these precious metals on organisms remain unclear, the induction of heat shock proteins (hsp70) in zebra mussels (Dreissena polymorpha) following exposure to soluble salts of platinum, palladium and rhodium was compared with the hsp70 induction in mussels following exposure to cadmium and lead. Mussels were sampled weekly during a period of 10 weeks and analyzed for their metal concentration and their hsp70 level. Highest metal uptake was found for Cd, followed by Pt, Pb and Pd. Rh demonstrated the lowest uptake rate. A clear time-dependent increase of hsp70 levels occurred in all exposed mussels. Concentrations of hsp70 started to rise between days 18 and 25, except for the Pt-exposed group, where the initial increase was between days 25 and 32. All groups reached maximal hsp70 concentrations at day 39. Subsequently, hsp70 levels decreased to initial levels for the remaining exposure period. Threshold metal levels for the hsp70 induction varied among the metals and increased in the order: Rh < Pd {<=} Pb < Pt < Cd. Highest hsp70 values were found for mussels exposed to Pd, with a 25-fold higher level than in the controls, followed by Pt- and Rh-exposed mussels, which showed a 19-fold increase. The hsp70 levels of the mussels exposed to Cd and Pb were much lower, showing 6- and 12-fold higher values than the control, respectively. The clear induction of hsp70 due to exposure to Pt, Pd and Rh gives evidence for strong cellular effects of these metals, especially, when compared with lead and cadmium. Among the metals tested, Pd seems to have the highest potential as inducer for hsp70 production due to its low threshold level in combination with the

  10. Induction of heat shock proteins (hsp70) in the zebra mussel (Dreissena polymorpha) following exposure to platinum group metals (platinum, palladium and rhodium): Comparison with lead and cadmium exposures

    International Nuclear Information System (INIS)

    Singer, Christoph; Zimmermann, Sonja; Sures, Bernd

    2005-01-01

    An increasing number of papers concentrate on the availability and uptake of platinum group elements (PGE) by different organisms. These metals are discharged into the environment from different anthropogenic sources, such as automobile catalytic converters, hospitals and other medical institutions. As the effects of these precious metals on organisms remain unclear, the induction of heat shock proteins (hsp70) in zebra mussels (Dreissena polymorpha) following exposure to soluble salts of platinum, palladium and rhodium was compared with the hsp70 induction in mussels following exposure to cadmium and lead. Mussels were sampled weekly during a period of 10 weeks and analyzed for their metal concentration and their hsp70 level. Highest metal uptake was found for Cd, followed by Pt, Pb and Pd. Rh demonstrated the lowest uptake rate. A clear time-dependent increase of hsp70 levels occurred in all exposed mussels. Concentrations of hsp70 started to rise between days 18 and 25, except for the Pt-exposed group, where the initial increase was between days 25 and 32. All groups reached maximal hsp70 concentrations at day 39. Subsequently, hsp70 levels decreased to initial levels for the remaining exposure period. Threshold metal levels for the hsp70 induction varied among the metals and increased in the order: Rh < Pd ≤ Pb < Pt < Cd. Highest hsp70 values were found for mussels exposed to Pd, with a 25-fold higher level than in the controls, followed by Pt- and Rh-exposed mussels, which showed a 19-fold increase. The hsp70 levels of the mussels exposed to Cd and Pb were much lower, showing 6- and 12-fold higher values than the control, respectively. The clear induction of hsp70 due to exposure to Pt, Pd and Rh gives evidence for strong cellular effects of these metals, especially, when compared with lead and cadmium. Among the metals tested, Pd seems to have the highest potential as inducer for hsp70 production due to its low threshold level in combination with the

  11. NK cells of the oldest seniors represent constant and resistant to stimulation high expression of cellular protective proteins SIRT1 and HSP70.

    Science.gov (United States)

    Kaszubowska, Lucyna; Foerster, Jerzy; Kaczor, Jan Jacek; Schetz, Daria; Ślebioda, Tomasz Jerzy; Kmieć, Zbigniew

    2018-01-01

    Natural killer cells (NK cells) are cytotoxic lymphocytes of innate immunity that reveal some immunoregulatory properties, however, their role in the process of ageing is not completely understood. The study aimed to analyze the expression of proteins involved in cellular stress response: sirtuin 1 (SIRT1), heat shock protein 70 (HSP70) and manganese superoxide dismutase (SOD2) in human NK cells with reference to the process of ageing. Non-stimulated and stimulated with IL-2, LPS or PMA with ionomycin cells originated from peripheral blood samples of: seniors aged over 85 ('the oldest'; n  = 25; 88.5 ± 0.5 years, mean ± SEM), seniors aged under 85 ('the old'; n  = 30; 75.6 ± 0.9 years) and the young ( n  = 31; 20.9 ± 0.3 years). The relationships between the levels of expression of cellular protective proteins in the studied population were also analyzed. The concentrations of carbonyl groups and 8-isoprostanes, markers of oxidative stress, in both stimulated and non-stimulated cultured NK cells were measured to assess the level of the oxidative stress in the cells. The oldest seniors varied from the other age groups by significantly higher expression of SIRT1 and HSP70 both in non-stimulated and stimulated NK cells. These cells also appeared to be resistant to further stimulations with IL-2, LPS or PMA with ionomycin. Highly positive correlations between SIRT1 and intracellular HSP70 in both stimulated and non-stimulated NK cells were observed. SOD2 presented low expression in non-stimulated cells, whereas its sensitivity to stimulation increased with age of donors. High positive correlations between SOD2 and surface HSP70 were observed. We found that the markers of oxidative stress in NK cells did not change with ageing. The oldest seniors revealed well developed adaptive stress response in NK cells with increased, constant levels of SIRT1 and intracellular HSP70. They presented also very high positive correlations between

  12. Computational Analysis of Residue Interaction Networks and Coevolutionary Relationships in the Hsp70 Chaperones: A Community-Hopping Model of Allosteric Regulation and Communication.

    Directory of Open Access Journals (Sweden)

    Gabrielle Stetz

    2017-01-01

    Full Text Available Allosteric interactions in the Hsp70 proteins are linked with their regulatory mechanisms and cellular functions. Despite significant progress in structural and functional characterization of the Hsp70 proteins fundamental questions concerning modularity of the allosteric interaction networks and hierarchy of signaling pathways in the Hsp70 chaperones remained largely unexplored and poorly understood. In this work, we proposed an integrated computational strategy that combined atomistic and coarse-grained simulations with coevolutionary analysis and network modeling of the residue interactions. A novel aspect of this work is the incorporation of dynamic residue correlations and coevolutionary residue dependencies in the construction of allosteric interaction networks and signaling pathways. We found that functional sites involved in allosteric regulation of Hsp70 may be characterized by structural stability, proximity to global hinge centers and local structural environment that is enriched by highly coevolving flexible residues. These specific characteristics may be necessary for regulation of allosteric structural transitions and could distinguish regulatory sites from nonfunctional conserved residues. The observed confluence of dynamics correlations and coevolutionary residue couplings with global networking features may determine modular organization of allosteric interactions and dictate localization of key mediating sites. Community analysis of the residue interaction networks revealed that concerted rearrangements of local interacting modules at the inter-domain interface may be responsible for global structural changes and a population shift in the DnaK chaperone. The inter-domain communities in the Hsp70 structures harbor the majority of regulatory residues involved in allosteric signaling, suggesting that these sites could be integral to the network organization and coordination of structural changes. Using a network-based formalism of

  13. Resistência à Síndrome Ascítica, Competência Homeotérmica e Níveis de Hsp70 no Coração e Pulmão de Frangos de Corte Resistance to Ascites Syndrome, Homoeothermic Competence and Levels of Hsp70 in the Heart and Lung of Broilers

    Directory of Open Access Journals (Sweden)

    Renata Hernandes

    2002-06-01

    Full Text Available Como em outros seres vivos, também nas células das aves ocorre a síntese das proteínas de baixo peso molecular (Hsp, cujo aumento é induzido sob condições de estresse. As Hsps têm um papel importante na manutenção da integridade celular, questiona-se o seu envolvimento no mecanismo de proteção celular de órgãos alvos na ocorrência da síndrome ascítica (SA. Este trabalho objetivou avaliar a temperatura corporal e os níveis da Hsp70 no coração e pulmão de frangos de corte Hubbard (sensível à SA e caipira de pescoço-pelado (resistente, criados em termoneutralidade (25°C e frio (16°C entre 10 e 45 dias de idade. Foram utilizados 192 pintos machos, 96 de cada linhagem. Não houve mortalidade por SA nas aves caipiras. Nas aves Hubbard, a mortalidade devida à SA foi de 4% e 41% em ambiente termoneutro e frio, respectivamente. Em ambiente frio, a temperatura corporal das aves Hubbard foi menor que a das caipiras. A temperatura corporal e o nível de Hsp70 do coração das aves Hubbard diminuíram com o aumento da idade, mas não nas aves caipiras, os quais se mantiveram constantes, inclusive a Hsp70 do pulmão. Independente da idade ou da temperatura, o nível de Hsp70 no pulmão das aves caipiras era superior ao das aves Hubbard. Em relação às aves Hubbard, as caipiras são homeotérmicas mais competentes e apresentam uma maior indução de Hsp70 nos órgãos primariamente afetados na SA, mas este não parece ser o sistema de proteção contra SA, a qual as aves de pescoço pelado são resistentes.Similar to other living animals, the cells of the birds also synthesize small proteins (heat shock protein, Hsp, which increasing levels can be induce by stress. The Hsp have a relevant function in maintaining the integrity of the cell, and we question if they are involved in the mechanism of the cellular protection of target organs affected by ascites syndrome (AS. The objective of this study was to evaluate the body temperature

  14. Gene expression of Hsp70, Hsp90 and Hsp110 families in normal palate and cleft palate during mouse embryogenesis.

    Science.gov (United States)

    Zhu, Yongfei; Ren, Chuanlu; Wan, Xuying; Zhu, Yuping; Zhu, Jiangbo; Zhou, Hongyuan; Zhang, Tianbao

    2013-11-01

    Most previous studies focused on a small number of heat shock proteins (Hsps) and their relationships with embryogenesis, and the actual roles of these Hsps in normal and abnormal embryonic development remain unclear. It was found in the present systemic study that except for Grp170, whose expression was not detectable at GD18, all 19 Hsps of Hsp70, Hsp90 and Hsp110 families were expressed in the normal development of embryonic palate tissue in mice, but their expression patterns varied with different Hsps, presenting as a correlation with the developmental phases. In the treatment group by all-trans retinoic acid (atRA), the messenger RNA (mRNA) abundance of HspA1A, HspA1L, HspA8, HspA9, HspA12A, HspA12B, HspA13, HspA14, Hsp90AA1, Hsp90AB1, Grp94, Trap1, Hsp105, Hsp110 and Grp170 was higher in the palates at GD11 (the beginning of palate development), the mRNA abundance of HspA1A, HspA12A and HspA12B was higher at GD18 (before birth) and an mRNA expression peak of HspA1L, HspA8, HspA9, Hsp90AA1, Grp94, Hsp110 and Grp170 was observed at GD17. The mRNA abundance of most genes in atRA-induced cleft palates of the treatment group was different from that of the control group. Grp78, HspA14 and Hsp105 were closely associated with the normal palate development and cleft palate in mouse embryo, possibly as palate development-related genes. Except Grp170, the other genes may be closely associated with the development of mouse palates through participating in the stress response process and/or the antiapoptosis process.

  15. Phylogenetic analysis of HSP70 and cyt b gene sequences for Chinese Leishmania isolates and ultrastructural characteristics of Chinese Leishmania sp.

    Science.gov (United States)

    Yuan, Dongmei; Qin, Hanxiao; Zhang, Jianguo; Liao, Lin; Chen, Qiwei; Chen, Dali; Chen, Jianping

    2017-02-01

    Leishmaniasis is a worldwide epidemic disease caused by the genus Leishmania, which is still endemic in the west and northwest areas of China. Some viewpoints of the traditional taxonomy of Chinese Leishmania have been challenged by recent phylogenetic researches based on different molecular markers. However, the taxonomic positions and phylogenetic relationships of Chinese Leishmania isolates remain controversial, which need for more data and further analysis. In this study, the heat shock protein 70 (HSP70) gene and cytochrome b (cyt b) gene were used for phylogenetic analysis of Chinese Leishmania isolates from patients, dogs, gerbils, and sand flies in different geographic origins. Besides, for the interesting Leishmania sp. in China, the ultrastructure of three Chinese Leishmania sp. strains (MHOM/CN/90/SC10H2, SD, GL) were observed by transmission electron microscopy. Bayesian trees from HSP70 and cyt b congruently indicated that the 14 Chinese Leishmania isolates belong to three Leishmania species including L. donovani complex, L. gerbilli, and L. (Sauroleishmania) sp. Their identity further confirmed that the undescribed Leishmania species causing visceral Leishmaniasis (VL) in China is closely related to L. tarentolae. The phylogenetic results from HSP70 also suggested the classification of subspecies within L. donovani complex: KXG-918, KXG-927, KXG-Liu, KXG-Xu, 9044, SC6, and KXG-65 belong to L. donovani; Cy, WenChuan, and 801 were proposed to be L. infantum. Through transmission electron microscopy, unexpectedly, the Golgi apparatus were not observed in SC10H2, SD, and GL, which was similar to previous reports of reptilian Leishmania. The statistical analysis of microtubule counts separated SC10H2, SD, and GL as one group from any other reference strain (L. donovani MHOM/IN/80/DD8; L. tropica MHOM/SU/74/K27; L. gerbilli MRHO/CN/60/GERBILLI). The ultrastructural characteristics of Leishmania sp. partly lend support to the phylogenetic inference that

  16. Influence of Moringa oleifera extract, vitamin C, and sodium bicarbonate on heat stress-induced HSP70 expression and cellular immune response in rabbits.

    Science.gov (United States)

    Abdel-Latif, Mahmoud; Sakran, Thabet; Badawi, Yasser K; Abdel-Hady, Doaa S

    2018-05-04

    The current study aimed to test the effect of Moringa oleifera extract (MOE), vitamin (Vit) C, and sodium bicarbonate (NaHCO 3 ) on heat stress (HS)-induced alterations in rabbits. Five groups of rabbits were designed as control, HS, HS + MOE, HS + Vit C, and HS + NaHCO 3 . HS groups were exposed to high temperatures, while treatments were given in drinking water for 6 weeks. Levels of blood cortisol, leptin, IFN-γ, TNF-α, and IL-10 were assayed using ELISA, while adrenaline was assayed calorimetrically. Expression of HSP70, FOXP3, T cell receptor (TCR) γ, and δ mRNA was tested using real-time (RT)-PCR, while HSP70 protein expression was tested using western blotting in liver and kidney tissues. Infiltration of regulatory T cells (Treg; CD25 + ) and NK (CD56 + ) cells were tested using immunohistochemistry (IHC). The levels of liver enzymes (ALT & AST), urea, and creatinine were assayed calorimetrically, while body weight gain (BWG) and feed conversion ratio (FCR) were calculated. The results showed increased levels of cortisol, adrenaline, leptin, IFN-γ, TNF-α, ALT, AST, urea, and creatinine but decreased IL-10 in the HS group. Increased expression of HSP70 on both mRNA and protein levels was associated with increased NK and γδ T cells versus decreased Treg cell infiltration in liver and kidney tissues of the HS group. In the same group, BWG was decreased, while FCR was increased with respect to the control group. All treatments used in this study reversed the effects of HS significantly. In conclusion, MOE, Vit C, and NaHCO 3 can be added to rabbit diets for the amelioration of HS-induced symptoms.

  17. A novel TaqMan® assay for Nosema ceranae quantification in honey bee, based on the protein coding gene Hsp70.

    Science.gov (United States)

    Cilia, Giovanni; Cabbri, Riccardo; Maiorana, Giacomo; Cardaio, Ilaria; Dall'Olio, Raffaele; Nanetti, Antonio

    2018-04-01

    Nosema ceranae is now a widespread honey bee pathogen with high incidence in apiculture. Rapid and reliable detection and quantification methods are a matter of concern for research community, nowadays mainly relying on the use of biomolecular techniques such as PCR, RT-PCR or HRMA. The aim of this technical paper is to provide a new qPCR assay, based on the highly-conserved protein coding gene Hsp70, to detect and quantify the microsporidian Nosema ceranae affecting the western honey bee Apis mellifera. The validation steps to assess efficiency, sensitivity, specificity and robustness of the assay are described also. Copyright © 2018 Elsevier GmbH. All rights reserved.

  18. Decipher the mechanisms of protein conformational changes induced by nucleotide binding through free-energy landscape analysis: ATP binding to Hsp70.

    Directory of Open Access Journals (Sweden)

    Adrien Nicolaï

    Full Text Available ATP regulates the function of many proteins in the cell by transducing its binding and hydrolysis energies into protein conformational changes by mechanisms which are challenging to identify at the atomic scale. Based on molecular dynamics (MD simulations, a method is proposed to analyze the structural changes induced by ATP binding to a protein by computing the effective free-energy landscape (FEL of a subset of its coordinates along its amino-acid sequence. The method is applied to characterize the mechanism by which the binding of ATP to the nucleotide-binding domain (NBD of Hsp70 propagates a signal to its substrate-binding domain (SBD. Unbiased MD simulations were performed for Hsp70-DnaK chaperone in nucleotide-free, ADP-bound and ATP-bound states. The simulations revealed that the SBD does not interact with the NBD for DnaK in its nucleotide-free and ADP-bound states whereas the docking of the SBD was found in the ATP-bound state. The docked state induced by ATP binding found in MD is an intermediate state between the initial nucleotide-free and final ATP-bound states of Hsp70. The analysis of the FEL projected along the amino-acid sequence permitted to identify a subset of 27 protein internal coordinates corresponding to a network of 91 key residues involved in the conformational change induced by ATP binding. Among the 91 residues, 26 are identified for the first time, whereas the others were shown relevant for the allosteric communication of Hsp70 s in several experiments and bioinformatics analysis. The FEL analysis revealed also the origin of the ATP-induced structural modifications of the SBD recently measured by Electron Paramagnetic Resonance. The pathway between the nucleotide-free and the intermediate state of DnaK was extracted by applying principal component analysis to the subset of internal coordinates describing the transition. The methodology proposed is general and could be applied to analyze allosteric communication in

  19. A novel Hsp70 of the yeast ER lumen is required for the efficient translocation of a number of protein precursors.

    OpenAIRE

    Craven, R A; Egerton, M; Stirling, C J

    1996-01-01

    The yeast genome sequencing project predicts an open reading frame (YKL073) that would encode a novel member of the Hsp70 family of molecular chaperones. We report that this 881 codon reading frame represents a functional gene expressing a 113-119 kDa glycoprotein localized within the lumen of the endoplasmic reticulum (ER). We therefore propose to designate this gene LHS1 (Lumenal Hsp Seventy). Our studies indicate that LHS1 is regulated by the unfolded protein response pathway, as evidenced...

  20. Beta-mangostin from Cratoxylum arborescens activates the intrinsic apoptosis pathway through reactive oxygen species with downregulation of the HSP70 gene in the HL60 cells associated with a G0/G1 cell-cycle arrest.

    Science.gov (United States)

    Omer, Fatima Abdelmutaal Ahmed; Hashim, Najihah Binti Mohd; Ibrahim, Mohamed Yousif; Dehghan, Firouzeh; Yahayu, Maizatulakmal; Karimian, Hamed; Salim, Landa Zeenelabdin Ali; Mohan, Syam

    2017-11-01

    Xanthones are phytochemical compounds found in a number of fruits and vegetables. Characteristically, they are noted to be made of diverse properties based on their biological, biochemical, and pharmacological actions. Accordingly, the apoptosis mechanisms induced by beta-mangostin, a xanthone compound isolated from Cratoxylum arborescens in the human promyelocytic leukemia cell line (HL60) in vitro, were examined in this study. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay was done to estimate the cytotoxicity effect of β-mangostin on the HL60 cell line. Acridine orange/propidium iodide and Hoechst 33342 dyes and Annexin V tests were conducted to detect the apoptosis features. Caspase-3 and caspase-9 activities; reactive oxygen species; real-time polymerase chain reaction for Bcl-2, Bax, caspase-3, and caspase-9 Hsp70 genes; and western blot for p53, cytochrome c, and pro- and cleavage-caspase-3 and caspase-9 were assessed to examine the apoptosis mechanism. Cell-cycle analysis conducted revealed that β-mangostin inhibited the growth of HL60 at 58 µM in 24 h. The administration of β-mangostin with HL60 caused cell morphological changes related to apoptosis which increased the number of early and late apoptotic cells. The β-mangostin-catalyzed apoptosis action through caspase-3, caspase-7, and caspase-9 activation overproduced reactive oxygen species which downregulated the expression of antiapoptotic genes Bcl-2 and HSP70. Conversely, the expression of the apoptotic genes Bax, caspase-3, and caspase-9 were upregulated. Meanwhile, at the protein level, β-mangostin activated the formation of cleaved caspase-3 and caspase-9 and also upregulated the p53. β-mangostin arrested the cell cycle at the G 0 /G 1 phase. Overall, the results for β-mangostin showed an antiproliferative effect in HL60 via stopping the cell cycle at the G 0 /G 1 phase and prompted the intrinsic apoptosis pathway.

  1. Suppression of cadmium-induced JNK/p38 activation and HSP70 family gene expression by LL-Z1640-2 in NIH3T3 cells

    International Nuclear Information System (INIS)

    Sugisawa, Nobusuke; Matsuoka, Masato; Okuno, Takeo; Igisu, Hideki

    2004-01-01

    When NIH3T3 cells were exposed to CdCl 2 , the three major mitogen-activated protein kinases (MAPKs), extracellular signal-regulated protein kinase (ERK), c-Jun NH 2 -terminal kinase (JNK), and p38, were phosphorylated in a time (1-9 h)- and dose (1-20 μM)-dependent manner. Treatment with a macrocyclic nonaketide compound, LL-Z1640-2 (10-100 ng/ml), suppressed the phosphorylation of MAPKs without affecting the total protein level in cells exposed to 10 μM CdCl 2 for 6 h. CdCl 2 -induced phosphorylation of c-Jun on Ser63 and that on Ser73, and resultant accumulation of total c-Jun protein were also suppressed by LL-Z1640-2 treatment. The in vitro kinase assays also showed significant inhibitory effects of LL-Z1640-2 (at 10 or 25 ng/ml) on JNK and p38 but less markedly. In contrast to JNK and p38, ERK activity was inhibited moderately only at 50 or 100 ng/ml LL-Z1640-2. On the other hand, other JNK inhibitors, SP600125 and L-JNKI1, failed to suppress CdCl 2 -induced activation of the JNK pathway. Among the mouse stress response genes upregulated in response to CdCl 2 exposure, the expressions of hsp68 (encoding for heat shock 70 kDa protein 1; Hsp70-1) and grp78 (encoding for 78 kDa glucose-regulated protein; Grp78) genes were suppressed by treatment with 25 ng/ml LL-Z1640-2. Thus, LL-Z1640-2 could suppress CdCl 2 -induced activation of JNK/p38 pathways and expression of HSP70 family genes in NIH3T3 cells. LL-Z1640-2 seems to be useful to analyze functions of toxic metal-induced JNK/p38 activation

  2. Quantitative proteomics and network analysis of SSA1 and SSB1 deletion mutants reveals robustness of chaperone HSP70 network in Saccharomyces cerevisiae.

    Science.gov (United States)

    Jarnuczak, Andrew F; Eyers, Claire E; Schwartz, Jean-Marc; Grant, Christopher M; Hubbard, Simon J

    2015-09-01

    Molecular chaperones play an important role in protein homeostasis and the cellular response to stress. In particular, the HSP70 chaperones in yeast mediate a large volume of protein folding through transient associations with their substrates. This chaperone interaction network can be disturbed by various perturbations, such as environmental stress or a gene deletion. Here, we consider deletions of two major chaperone proteins, SSA1 and SSB1, from the chaperone network in Sacchromyces cerevisiae. We employ a SILAC-based approach to examine changes in global and local protein abundance and rationalise our results via network analysis and graph theoretical approaches. Although the deletions result in an overall increase in intracellular protein content, correlated with an increase in cell size, this is not matched by substantial changes in individual protein concentrations. Despite the phenotypic robustness to deletion of these major hub proteins, it cannot be simply explained by the presence of paralogues. Instead, network analysis and a theoretical consideration of folding workload suggest that the robustness to perturbation is a product of the overall network structure. This highlights how quantitative proteomics and systems modelling can be used to rationalise emergent network properties, and how the HSP70 system can accommodate the loss of major hubs. © 2015 The Authors. PROTEOMICS published by Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Detection and identification of Leishmania spp.: application of two hsp70-based PCR-RFLP protocols to clinical samples from the New World.

    Science.gov (United States)

    Montalvo, Ana M; Fraga, Jorge; Tirado, Dídier; Blandón, Gustavo; Alba, Annia; Van der Auwera, Gert; Vélez, Iván Darío; Muskus, Carlos

    2017-07-01

    Leishmaniasis is highly prevalent in New World countries, where several methods are available for detection and identification of Leishmania spp. Two hsp70-based PCR protocols (PCR-N and PCR-F) and their corresponding restriction fragment length polymorphisms (RFLP) were applied for detection and identification of Leishmania spp. in clinical samples recruited in Colombia, Guatemala, and Honduras. A total of 93 cases were studied. The samples were classified into positive or suspected of leishmaniasis according to parasitological criteria. Molecular amplification of two different hsp70 gene fragments and further RFLP analysis for identification of Leishmania species was done. The detection in parasitologically positive samples was higher using PCR-N than PCR-F. In the total of samples studied, the main species identified were Leishmania panamensis, Leishmania braziliensis, and Leishmania infantum (chagasi). Although RFLP-N was more efficient for the identification, RFLP-F is necessary for discrimination between L. panamensis and Leishmania guyanesis, of great importance in Colombia. Unexpectedly, one sample from this country revealed an RFLP pattern corresponding to Leishmania naiffi. Both molecular variants are applicable for the study of clinical samples originated in Colombia, Honduras, and Guatemala. Choosing the better tool for each setting depends on the species circulating. More studies are needed to confirm the presence of L. naiffi in Colombian territory.

  4. Histopathological alterations and induction of hsp70 in ramshorn snail (Marisa cornuarietis) and zebrafish (Danio rerio) embryos after exposure to PtCl(2).

    Science.gov (United States)

    Osterauer, Raphaela; Köhler, Heinz-R; Triebskorn, Rita

    2010-08-01

    The platinum group metals (PGMs) platinum (Pt), palladium (Pd), and rhodium (Rh) are used in automobile catalytic converters, from which they have been emitted into the environment to an increasing degree during the last 20 years. Despite the bioavailability of these metals to plants and animals, studies determining the effects of PGMs on organisms are extremely rare. In the present study, effects of various concentrations of PtCl(2) (0.1, 1, 10, 50 and 100 microg/L) were investigated with respect to the induction of hsp70 and histopathological alterations in the zebrafish, Danio rerio and the ramshorn snail, Marisa cornuarietis. Histopathological investigations revealed effects of Pt on both species, which varied between slight and strong cellular reactions, depending on the PtCl(2) concentration. The hsp70 level in M. cornuarietis did not show an increase following Pt exposure whereas it was significantly elevated at 100 micorg/L PtCl(2) in D. rerio. Copyright 2010 Elsevier B.V. All rights reserved.

  5. The Hsp70 homolog Ssb and the 14-3-3 protein Bmh1 jointly regulate transcription of glucose repressed genes in Saccharomyces cerevisiae.

    Science.gov (United States)

    Hübscher, Volker; Mudholkar, Kaivalya; Chiabudini, Marco; Fitzke, Edith; Wölfle, Tina; Pfeifer, Dietmar; Drepper, Friedel; Warscheid, Bettina; Rospert, Sabine

    2016-07-08

    Chaperones of the Hsp70 family interact with a multitude of newly synthesized polypeptides and prevent their aggregation. Saccharomyces cerevisiae cells lacking the Hsp70 homolog Ssb suffer from pleiotropic defects, among others a defect in glucose-repression. The highly conserved heterotrimeric kinase SNF1/AMPK (AMP-activated protein kinase) is required for the release from glucose-repression in yeast and is a key regulator of energy balance also in mammalian cells. When glucose is available the phosphatase Glc7 keeps SNF1 in its inactive, dephosphorylated state. Dephosphorylation depends on Reg1, which mediates targeting of Glc7 to its substrate SNF1. Here we show that the defect in glucose-repression in the absence of Ssb is due to the ability of the chaperone to bridge between the SNF1 and Glc7 complexes. Ssb performs this post-translational function in concert with the 14-3-3 protein Bmh, to which Ssb binds via its very C-terminus. Raising the intracellular concentration of Ssb or Bmh enabled Glc7 to dephosphorylate SNF1 even in the absence of Reg1. By that Ssb and Bmh efficiently suppressed transcriptional deregulation of Δreg1 cells. The findings reveal that Ssb and Bmh comprise a new chaperone module, which is involved in the fine tuning of a phosphorylation-dependent switch between respiration and fermentation. © The Author(s) 2016. Published by Oxford University Press on behalf of Nucleic Acids Research.

  6. Evaluation of the toxic potential of calcium carbide in the third instar larvae of transgenic Drosophila melanogaster (hsp70-lacZ)Bg(9).

    Science.gov (United States)

    Danish, Mohd; Fatima, Ambreen; Khanam, Saba; Jyoti, Smita; Rahul; Ali, Fahad; Naz, Falaq; Siddique, Yasir Hasan

    2015-11-01

    In the present study the toxic potential of calcium carbide (CaC2) was studied on the third instar larvae of transgenic Drosophila melanogaster (hsp70-lacZ)Bg(9). The third instar larvae were exposed to 2, 4, 8, 16 and 32×10(-3)g/ml of CaC2 in diet for 24h. The results reveal that the dose 2×10(-3)g/ml was not toxic but the remaining doses showed a dose dependent significant increase in the hsp70 expression, β-galactosidase activity, tissue damage, oxidative stress markers (lipid peroxidation and protein carbonyl content), glutathione-S-transferase activity, expression of Caspase 3 and 9, apoptotic index and DNA damage (midgut cells). A significant reduction as compared to control group in total protein, glutathione content and acetylcholinesterase activity was also observed. The Inductively Coupled Plasma Atomic Emission Spectroscopy analysis (ICPAES) reveals the presence of copper, iron, sodium, aluminium, manganese, calcium, nickel and mercury. The toxic effects of CaC2 in the present study may be attributed to the impurities present in it. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Non-invasive assessment of animal exercise stress: real-time PCR of GLUT4, COX2, SOD1 and HSP70 in avalanche military dog saliva.

    Science.gov (United States)

    Diverio, S; Guelfi, G; Barbato, O; Di Mari, W; Egidi, M G; Santoro, M M

    2015-01-01

    Exercise has been shown to increase mRNA expression of a growing number of genes. The aim of this study was to assess if mRNA expression of the metabolism- and oxidative stress-related genes GLUT4 (glucose transporter 4), COX2 (cyclooxygenase 2), SOD1 (superoxide dismutase 1) and HSP70 (heat shock protein 70) in saliva changes following acute exercise stress in dogs. For this purpose, 12 avalanche dogs of the Italian Military Force Guardia di Finanza were monitored during simulation of a search for a buried person in an artificial avalanche area. Rectal temperature (RT) and saliva samples were collected the day before the trial (T0), immediately after the descent from a helicopter at the onset of a simulated avalanche search and rescue operation (T1), after the discovery of the buried person (T2) and 2 h later (T3). Expressions of GLUT4, SOD1, COX2 and HSP70 were measured by real-time PCR. The simulated avalanche search and rescue operation was shown to exert a significant effect on RT, as well as on the expression of all metabolism- and oxidative stress-related genes investigated, which peaked at T2. The observed expression patterns indicate an acute exercise stress-induced upregulation, as confirmed by the reductions in expression at T3. Moreover, our findings indicate that saliva is useful for assessing metabolism- and oxidative stress-related genes without the need for restraint, which could affect working dog performance.

  8. In contrast to conventional inactivated influenza vaccines, 4xM2e.HSP70c fusion protein fully protected mice against lethal dose of H1, H3 and H9 influenza A isolates circulating in Iran

    Energy Technology Data Exchange (ETDEWEB)

    Ebrahimi, Seyyed Mahmoud, E-mail: smebrahimi@shirazu.ac.ir [Applied Biotechnology Research Center, Baqiyatallah University of Medical Sciences, P.O. Box 14155-3651,Tehran (Iran, Islamic Republic of); Research Center of Virus and Vaccine, Baqiyatallah University of Medical Science, P.O.Box 14155-3651, Tehran (Iran, Islamic Republic of); Dabaghian, Mehran [Department of Pathobiology, University of Tehran, Faculty of Veterinary Medicine, P.O. Box 14155-6453, Tehran (Iran, Islamic Republic of); Tebianian, Majid [Department of Biotechnology, Razi Vaccine and Serum Research Institute (RVSRI), P.O. Box 31975/148, Karaj, Tehran (Iran, Islamic Republic of); Zabeh Jazi, Mohammad Hossein [Department of Pathobiology, University of Tehran, Faculty of Veterinary Medicine, P.O. Box 14155-6453, Tehran (Iran, Islamic Republic of)

    2012-08-15

    Ideal vaccines against influenza viruses should elicit not only a humoral response, but also a cellular response. Mycobacterium tuberculosis HSP70 (mHSP70) have been found to promote immunogenic APCs function, elicit a strong cytotoxic T lymphocyte (CTL) response, and prevent the induction of tolerance. Moreover, it showed linkage of antigens to the C-terminus of mHSP70 (mHSP70c) can represent them as vaccines resulted in more potent, protective antigen specific responses in the absence of adjuvants or complex formulations. Hence, recombinant fusion protein comprising C-terminus of mHSP70 genetically fused to four tandem repeats of the ectodomain of the conserved influenza matrix protein M2 (M2e) was expressed in Escherichia coli, purified under denaturing condition, refolding, and then confirmed by SDS-PAGE, respectively. The recombinant fusion protein, 4xM2e.HSP70c, retained its immunogenicity and displayed the protective epitope of M2e by ELISA and FITC assays. A prime-boost administration of 4xM2e.HSP70c formulated in F105 buffer by intramuscular route in mice (Balb/C) provided full protection against lethal dose of mouse-adapted H1N1, H3N2, or H9N2 influenza A isolates from Iran compared to 0-33.34% survival rate of challenged unimmunized and immunized mice with the currently in use conventional vaccines designated as control groups. However, protection induced by immunization with 4xM2e.HSP70c failed to prevent weight loss in challenged mice; they experienced significantly lower weight loss, clinical symptoms and higher lung viral clearance in comparison with protective effects of conventional influenza vaccines in challenged mice. These data demonstrate that C-terminal domain of mHSP70 can be a superior candidate to deliver the adjuvant function in M2e-based influenza A vaccine in order to provide significant protection against multiple influenza A virus strains.

  9. In contrast to conventional inactivated influenza vaccines, 4xM2e.HSP70c fusion protein fully protected mice against lethal dose of H1, H3 and H9 influenza A isolates circulating in Iran

    International Nuclear Information System (INIS)

    Ebrahimi, Seyyed Mahmoud; Dabaghian, Mehran; Tebianian, Majid; Zabeh Jazi, Mohammad Hossein

    2012-01-01

    Ideal vaccines against influenza viruses should elicit not only a humoral response, but also a cellular response. Mycobacterium tuberculosis HSP70 (mHSP70) have been found to promote immunogenic APCs function, elicit a strong cytotoxic T lymphocyte (CTL) response, and prevent the induction of tolerance. Moreover, it showed linkage of antigens to the C-terminus of mHSP70 (mHSP70c) can represent them as vaccines resulted in more potent, protective antigen specific responses in the absence of adjuvants or complex formulations. Hence, recombinant fusion protein comprising C-terminus of mHSP70 genetically fused to four tandem repeats of the ectodomain of the conserved influenza matrix protein M2 (M2e) was expressed in Escherichia coli, purified under denaturing condition, refolding, and then confirmed by SDS–PAGE, respectively. The recombinant fusion protein, 4xM2e.HSP70c, retained its immunogenicity and displayed the protective epitope of M2e by ELISA and FITC assays. A prime-boost administration of 4xM2e.HSP70c formulated in F105 buffer by intramuscular route in mice (Balb/C) provided full protection against lethal dose of mouse-adapted H1N1, H3N2, or H9N2 influenza A isolates from Iran compared to 0–33.34% survival rate of challenged unimmunized and immunized mice with the currently in use conventional vaccines designated as control groups. However, protection induced by immunization with 4xM2e.HSP70c failed to prevent weight loss in challenged mice; they experienced significantly lower weight loss, clinical symptoms and higher lung viral clearance in comparison with protective effects of conventional influenza vaccines in challenged mice. These data demonstrate that C-terminal domain of mHSP70 can be a superior candidate to deliver the adjuvant function in M2e-based influenza A vaccine in order to provide significant protection against multiple influenza A virus strains.

  10. Effects of chronic thermal stress on growth performance, carcass traits, antioxidant indices and the expression of HSP70, growth hormone and superoxide dismutase genes in two broiler strains.

    Science.gov (United States)

    Roushdy, Elshimaa M; Zaglool, Asmaa W; El-Tarabany, Mahmoud S

    2018-05-01

    The objective was to investigate the effects of genetic type and the duration of chronic thermal stress (36 °C) on the growing efficiency, carcass traits, antioxidant status, and the expression of liver heat shock protein 70 (HSP70), growth hormone (GH) and superoxide dismutase (SOD) genes. Two hundred and seventy one-day-old chicks (135 male chicks of each breed; Ross 308 and Cobb 500) were used in this work. On the 21st day of age, birds were allocated randomly into 3 equal groups till the 42 days of age (CON:raised in a thermoneutral condition; HS 1 and HS 2 groups were subjected to 4 and 6 h of daily thermal stress, respectively). Regardless of genetic type, thermal stress decreased the dressing percentage in broilers when compared with the thermoneutral conditions (p = 0.039). In both broiler strains, thermal stress for 6 h (HS 2 ) increased the heterophil to lymphocyte ratio (p = 0.036) and the serum albumin, cholesterol and triglyceride levels (p = 0.023, 0.012 and 0.005, respectively) compared with the thermoneutral group. Under the thermonuteral and heat stress conditions, the Ross broiler chickens showed a significant lower serum triiodothyronine level compared with the Cobb boilers (p = 0.042). It is interesting to note that the expression of HSP70 in the liver of heat-stressed Ross broilers, either 4 or 6 h, was significantly (p = 0.002) higher than that reported in the heat-stressed Cobb broilers. In both broiler strains, the thermal stress for 6 h up-regulate the expression of SOD gene (p = 0.001), but down-regulate the expression of GH gene (p = 0.021) when compared with the CON group. In conclusion, chronic thermal stress down-regulate the mRNA expression of liver GH, concomitantly with an increase in the expression of HSP70 and SOD genes in both broiler strains. This could be useful in the identification of molecular genetic markers to assist in selecting broilers that are more tolerant to heat stress

  11. Combined effects of thermal stress and Cd on lysosomal biomarkers and transcription of genes encoding lysosomal enzymes and HSP70 in mussels, Mytilus galloprovincialis

    Energy Technology Data Exchange (ETDEWEB)

    Izagirre, Urtzi; Errasti, Aitzpea; Bilbao, Eider; Múgica, María; Marigómez, Ionan, E-mail: ionan.marigomez@ehu.es

    2014-04-01

    Highlights: • Thermal stress and Cd caused lysosomal enlargement and membrane destabilisation. • hex, gusb and ctsl but not hsp70 were up-regulated at elevated temperature but down-regulated by Cd. • Thermal stress influenced lysosomal responses to Cd exposure. • The presence of Cd jeopardised responsiveness against thermal stress. - Abstract: In estuaries and coastal areas, intertidal organisms may be subject to thermal stress resulting from global warming, together with pollution. In the present study, the combined effects of thermal stress and exposure to Cd were investigated in the endo-lysosomal system of digestive cells in mussels, Mytilus galloprovincialis. Mussels were maintained for 24 h at 18 °C and 26 °C seawater temperature in absence and presence of 50 μg Cd/L seawater. Cadmium accumulation in digestive gland tissue, lysosomal structural changes and membrane stability were determined. Semi-quantitative PCR was applied to reveal the changes elicited by the different experimental conditions in hexosaminidase (hex), β-glucuronidase (gusb), cathepsin L (ctsl) and heat shock protein 70 (hsp70) gene transcription levels. Thermal stress provoked lysosomal enlargement whilst Cd-exposure led to fusion of lysosomes. Both thermal stress and Cd-exposure caused lysosomal membrane destabilisation. hex, gusb and ctsl genes but not hsp70 gene were transcriptionally up-regulated as a result of thermal stress. In contrast, all the studied genes were transcriptionally down-regulated in response to Cd-exposure. Cd bioaccumulation was comparable at 18 °C and 26 °C seawater temperatures but interactions between thermal stress and Cd-exposure were remarkable both in lysosomal biomarkers and in gene transcription. hex, gusb and ctsl genes, reacted to elevated temperature in absence of Cd but not in Cd-exposed mussels. Therefore, thermal stress resulting from global warming might influence the use and interpretation of lysosomal biomarkers in marine pollution

  12. Evaluation of the toxic potential of aspartame in third instar larvae of transgenic Drosophila melanogaster (hsp70-lacZ) Bg9

    Energy Technology Data Exchange (ETDEWEB)

    Siddique, Y.H.; Anjum, S.; Rahul x, Smita Jyoti

    2017-07-01

    Aspartame is commonly used as a sweetener in prepared foods, beverages and in recipes. In the present study the possible toxic effects of aspartame were studied in third instar larvae of transgenic Drosophila melanogaster (hsp70-lacZ) Bg9. The third instar larvae were allowed to feed on the diet having different doses of aspartame. The results obtained in the present study suggest that the exposure of third instar larvae to the diet having 20, 40, 80, 160 and 320 mM of aspartame did not show any significant the toxic effects after 24 hours of the exposure compared to control (p<0.05). The results for pupae formation and emergence of flies also did not show any significant difference compared to control (p<0.05).

  13. Evaluation of the toxic potential of aspartame in third instar larvae of transgenic Drosophila melanogaster (hsp70-lacZ Bg9

    Directory of Open Access Journals (Sweden)

    YASIR HASAN SIDDIQUE

    2017-07-01

    Full Text Available Aspartame is commonly used as a sweetener in prepared foods, beverages and in recipes. In the present study the possible toxic effects of aspartame were studied in third instar larvae of transgenic Drosophila melanogaster (hsp70-lacZ Bg9. The third instar larvae were allowed to feed on the diet having different doses of aspartame. The results obtained in the present study suggest that the exposure of third instar larvae to the diet having 20, 40, 80, 160 and 320 mM of aspartame did not show any significant the toxic effects after 24 hours of the exposure compared to control (p<0.05. The results for pupae formation and emergence of flies also did not show any significant difference compared to control (p<0.05.

  14. Evaluation of the toxic potential of aspartame in third instar larvae of transgenic Drosophila melanogaster (hsp70-lacZ) Bg9

    International Nuclear Information System (INIS)

    Siddique, Y.H.; Anjum, S.; Rahul x, Smita Jyoti

    2017-01-01

    Aspartame is commonly used as a sweetener in prepared foods, beverages and in recipes. In the present study the possible toxic effects of aspartame were studied in third instar larvae of transgenic Drosophila melanogaster (hsp70-lacZ) Bg9. The third instar larvae were allowed to feed on the diet having different doses of aspartame. The results obtained in the present study suggest that the exposure of third instar larvae to the diet having 20, 40, 80, 160 and 320 mM of aspartame did not show any significant the toxic effects after 24 hours of the exposure compared to control (p<0.05). The results for pupae formation and emergence of flies also did not show any significant difference compared to control (p<0.05).

  15. Toxic Potential of Synthesized Graphene Zinc Oxide Nanocomposite in the Third Instar Larvae of Transgenic Drosophila melanogaster (hsp70-lacZBg9

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    Yasir Hasan Siddique

    2014-01-01

    Full Text Available In the present study the graphene zinc oxide nanocomposite (GZNC was synthesized, characterized, and evaluated for its toxic potential on third instar larvae of transgenic Drosophila melanogaster (hsp70-lacZBg9. The synthesized GZNC was characterized by X-ray diffraction (XRD, Fourier transform infrared spectroscopy (FTIR, thermogravimetric analysis (TGA, scanning electron microscopy (SEM, and transmission electron microscopy (TEM. The GZNC in 0.1% dimethyl sulphoxide (DMSO was sonicated for 10 minutes and the final concentrations 0.033, 0.099, 0.199, and 3.996 μg/μL of diet were established. The third instar larvae were allowed to feed on it separately for 24 and 48 hr. The hsp70 expression was measured by o-nitrophenyl-β-D-galactopyranoside assay, tissue damage was measured by trypan blue exclusion test, and β-galactosidase activity was monitored by in situ histochemical β-galactosidase staining. Oxidative stress was monitored by performing lipid peroxidation assay and total protein estimation. Ethidium bromide/acridine orange staining was performed on midgut cells for apoptotic index and the comet assay was performed for the DNA damage. The results of the present study showed that the exposure of 0.199 and 3.996 μg/μL of GZNC was toxic for both 24 hr and 48 hr of exposure. The doses of 0.033 μg/μL and 0.099 of GZNC showed no toxic effects on its exposure to the third instar larvae for 24 hr as well as 48 hr of duration.

  16. Hsp27, Hsp70, and metallothionein in MDCK and LLC-PK1 renal epithelial cells: effects of prolonged exposure to cadmium

    International Nuclear Information System (INIS)

    Bonham, Rita T.; Fine, Michael R.; Pollock, Fiona M.; Shelden, Eric A.

    2003-01-01

    Cadmium is a widely distributed industrial and environmental toxin. The principal target organ of chronic sublethal cadmium exposure is the kidney. In renal epithelial cells, acute high-dose cadmium exposure induces differential expression of proteins, including heat shock proteins. However, few studies have examined heat shock protein expression in cells after prolonged exposure to cadmium at sublethal concentrations. Here, we assayed total cell protein, neutral red uptake, cell death, and levels of metallothionein and heat shock proteins Hsp27 and inducible Hsp70 in cultures of MDCK and LLC-PK1 renal epithelial cells treated with cadmium for 3 days. Treatment with cadmium at concentrations equal to or greater than 10 μM (LLC-PK1) or 25 μM (MDCK) reduced measures of cell vitality and induced cell death. However, a concentration-dependent increase in Hsp27 was detected in both cell types treated with as little as 5 μM cadmium. Accumulation of Hsp70 was correlated only with cadmium treatment at concentrations also causing cell death. Metallothionein was maximally detected in cells treated with cadmium at concentrations that did not reduce cell vitality, and further increases were not detected at greater concentrations. These results reveal that heat shock proteins accumulate in renal epithelial cells during prolonged cadmium exposure, that cadmium induces differential expression of heat shock protein in epithelial cells, and that protein expression patterns in epithelial cells are specific to the cadmium concentration and degree of cellular injury. A potential role for Hsp27 in the cellular response to sublethal cadmium-induced injury is also implicated by our results

  17. Alteration of cytochrome P450 1 regulation and HSP 70 level in brain of juvenile common carp (Cyprinus carpio) after chronic exposure to tributyltin.

    Science.gov (United States)

    Li, Zhi-Hua; Zhong, Li-Qiao; Wu, Yan-Hua; Mu, Wei-Na

    2016-02-01

    Tributyltin (TBT), a toxic contaminant in aquatic environments, has bio-accumulated in aquatic food webs throughout the world and can be found at toxic levels in some biota. However, the molecular mechanisms and effects of TBT are not fully understood. The aim of the present study was to investigate the effect of long-term exposure of TBT on cytochrome P450 (CYP450) 1 regulation and heat-shock proteins (HSPs) profiling in brain of freshwater teleost. The effects of long-term exposure to TBT on mRNA expression of cytochrome P450 (CYP450) 1 family genes and ethoxyresorufin O-deethylase (EROD) activity in the brain of common carp were evaluated, as well as HSP 70 level. Fish were exposed to sublethal concentrations of TBT (75 ng/L, 0.75 μg/L and 7.5 μg/L) for 15, 30, and 60 days. Based on the results, long-term exposure (more than 15 days) to TBT could lead to obvious physiological-biochemical responses (based on EROD activity, HSP 70 level and CYP450 1 family genes expression). The mRNA expression of CYP450 1 family genes (CYP1A, CYP1B, CYP1C1 and CYP1C2) suggested that CYP1A was to accommodate most EROD activity in fish, but other CYP450 forms also involved in this proceeding. Thus, the measured physiological responses in fish brain could provide useful information to better understand the mechanisms of TBT-induced bio-toxicity and could be used as potential biomarkers for monitoring the TBT pollution in the field.

  18. Energy sources and levels influenced on performance parameters, thyroid hormones, and HSP70 gene expression of broiler chickens under heat stress.

    Science.gov (United States)

    Raghebian, Majid; Sadeghi, Ali Asghar; Aminafshar, Mehdi

    2016-12-01

    The present study was conducted to evaluate the effects of energy sources and levels on body and organs weights, thyroid hormones, and heat shock protein (HSP70) gene expression in broilers under heat stress. In a completely randomized design, 600 1-day-old Cobb chickens were assigned to five dietary treatments and four replicates. The chickens were fed diet based on corn as main energy source and energy level based on Cobb standard considered as control (C), corn-based diet with 3 % lesser energy than the control (T1), corn-based diet with 6 % lesser energy than the control (T2), corn and soybean oil-based diet according to Cobb standard (T3), and corn and soybean oil-based diet with 3 % upper energy than the control (T4). Temperature was increased to 34 °C for 8 h daily from days 12 to 41 of age to induce heat stress. The chickens in T1 and T2 had lower thyroid hormones and corticosterone levels than those in C, T3, and T4. The highest liver weight was for C and the lowest one was for T4. The highest gene expression was found in chickens fed T4 diet, and the lowest gene expression was for those in T2 group. The highest feed intake and worse feed conversion ratio was related to chickens in T2. The chickens in T3 and T4 had higher feed intake and weight gain than those in C. The results showed that the higher energy level supplied from soybean oil could enhance gene expression of HSP70 and decline the level of corticosterone and thyroid hormones and consequently improved performance.

  19. Methyl CpG level at distal part of heat-shock protein promoter HSP70 exhibits epigenetic memory for heat stress by modulating recruitment of POU2F1-associated nucleosome-remodeling deacetylase (NuRD) complex.

    Science.gov (United States)

    Kisliouk, Tatiana; Cramer, Tomer; Meiri, Noam

    2017-05-01

    Depending on its stringency, exposure to heat in early life leads to either resilience or vulnerability to heat stress later in life. We hypothesized that epigenetic alterations in genes belonging to the cell proteostasis pathways are attributed to long-term responses to heat stress. Epigenetic regulation of the mRNA expression of the molecular chaperone heat-shock protein (HSP) 70 (HSPA2) was evaluated in the chick hypothalamus during the critical period of thermal-control establishment on day 3 post-hatch and during heat challenge on day 10. Both the level and duration of HSP70 expression during heat challenge a week after heat conditioning were more pronounced in chicks conditioned under harsh versus mild temperature. Analyzing different segments of the promoter in vitro indicated that methylation of a distal part altered its transcriptional activity. In parallel, DNA-methylation level of this segment in vivo was higher in harsh- compared to mild-heat-conditioned chicks. Hypermethylation of the HSP70 promoter in high-temperature-conditioned chicks was accompanied by a reduction in both POU Class 2 Homeobox 1 (POU2F1) binding and recruitment of the nucleosome remodeling deacetylase (NuRD) chromatin-remodeling complex. As a result, histone H3 acetylation levels at the HSP70 promoter were higher in harsh-temperature-conditioned chicks than in their mild-heat-conditioned counterparts. These results suggest that methylation level of a distal part of the HSP70 promoter and POU2F1 recruitment may reflect heat-stress-related epigenetic memory and may be useful in differentiating between individuals that are resilient or vulnerable to stress. © 2017 International Society for Neurochemistry.

  20. Involvement of NF-ΚB and HSP70 signaling pathways in the apoptosis of MDA-MB-231 cells induced by a prenylated xanthone compound, α-mangostin, from Cratoxylum arborescens

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    Ibrahim MY

    2014-11-01

    the role of the central apoptosis-related proteins, a protein array followed by immunoblot analysis was conducted. Moreover, the involvement of nuclear factor-kappa B (NF-ΚB was also analyzed. Results: Apoptosis was confirmed by the apoptotic cells stained with annexin V and increase in chromatin condensation in nucleus. Treatment of cells with AM promoted cell death-transducing signals that reduced MMP by downregulation of Bcl-2 and upregulation of Bax, triggering cytochrome c release from the mitochondria to the cytosol. The released cytochrome c triggered the activation of caspase-9 followed by the executioner caspase-3/7 and then cleaved the PARP protein. Increase of caspase-8 showed the involvement of extrinsic pathway. AM treatment significantly arrested the cells at the S phase (P<0.05 concomitant with an increase in reactive oxygen species. The protein array and Western blotting demonstrated the expression of HSP70. Moreover, AM significantly blocked the induced translocation of NF-ΚB from cytoplasm to nucleus. Conclusion: Together, the results demonstrate that the AM isolated from C. arborescens inhibited the proliferation of MDA-MB-231 cells, leading to cell cycle arrest and programmed cell death, which was suggested to occur through both the extrinsic and intrinsic apoptosis pathways with involvement of the NF-ΚB and HSP70 signaling pathways. Keywords: mitochondria, protein array, caspase-3/7

  1. Expression of hsp70, hsp90 and hsf1 in the reef coral Acropora digitifera under prospective acidified conditions over the next several decades

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    Masako Nakamura

    2012-02-01

    Ocean acidification is an ongoing threat for marine organisms due to the increasing atmospheric CO2 concentration. Seawater acidification has a serious impact on physiologic processes in marine organisms at all life stages. On the other hand, potential tolerance to external pH changes has been reported in coral larvae. Information about the possible mechanisms underlying such tolerance responses, however, is scarce. In the present study, we examined the effects of acidified seawater on the larvae of Acropora digitifera at the molecular level. We targeted two heat shock proteins, Hsp70 and Hsp90, and a heat shock transcription factor, Hsf1, because of their importance in stress responses and in early life developmental stages. Coral larvae were maintained under the ambient and elevated CO2 conditions that are expected to occur within next 100 years, and then we evaluated the expression of hsps and hsf1 by quantitative real-time polymerase chain reaction (PCR. Expression levels of these molecules significantly differed among target genes, but they did not change significantly between CO2 conditions. These findings indicate that the expression of hsps is not changed due to external pH changes, and suggest that tolerance to acidified seawater in coral larvae may not be related to hsp expression.

  2. Cloning of three heat shock protein genes (HSP70, HSP90α and HSP90β) and their expressions in response to thermal stress in loach (Misgurnus anguillicaudatus) fed with different levels of vitamin C.

    Science.gov (United States)

    Yan, Jie; Liang, Xiao; Zhang, Yin; Li, Yang; Cao, Xiaojuan; Gao, Jian

    2017-07-01

    Heat shock protein 70 (HSP70) and 90 (HSP90) are the most broadly studied proteins in HSP families. They play key roles in cells as molecular chaperones, in response to stress conditions such as thermal stress. In this study, full-length cDNA sequences of HSP70, HSP90α and HSP90β from loach Misgurnus anguillicaudatus were cloned. The full-length cDNA of HSP70 in loach was 2332bp encoding 644 amino acids, while HSP90α and HSP90β were 2586bp and 2678bp in length, encoding 729 and 727 amino acids, respectively. The deduced amino acid sequences of HSP70 in loach shared the highest identity with those of Megalobrama amblycephala and Cyprinus carpio. The deduced amino acid sequences of HSP90α and HSP90β in loach both shared the highest identity with those of M. amblycephala. Their mRNA tissue expression results showed that the maximum expressions of HSP70, HSP90α and HSP90β were respectively present in the intestine, brain and kidney of loach. Quantitative real-time PCR was employed to analyze the temporal expressions of HSP70, HSP90α and HSP90β in livers of loaches fed with different levels of vitamin C under thermal stress. Expression levels of the three HSP genes in loach fed the diet without vitamin C supplemented at 0 h of thermal stress were significantly lower than those at 2 h, 6 h, 12 h and 24 h of thermal stress. It indicated that expressions of the three HSP genes were sensitive to thermal stress in loach. The three HSP genes in loaches fed with 1000 mg/kg vitamin C expressed significantly lower than other vitamin C groups at many time points of thermal stress, suggesting 1000 mg/kg dietary vitamin C might decrease the body damages caused by the thermal stress. This study will be of value for further studies into thermal stress tolerance in loach. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Clinical evaluation and mitochondrial DNA sequence analysis in two Chinese families with aminoglycoside-induced and non-syndromic hearing loss

    International Nuclear Information System (INIS)

    Zhao Lidong; Wang Qiuju; Qian Yaping; Li Ronghua; Cao Juayng; Hart, Laura Christine; Zhai Suoqiang; Han Dongyi; Young Wieyen; Guan Minxin

    2005-01-01

    We report here the clinical, genetic, and molecular characterization of two Chinese pedigrees with aminoglycoside-induced and non-syndromic hearing impairment. Clinical evaluation revealed the variable phenotype of hearing impairment including audiometric configuration in these subjects. Penetrances of hearing loss in BJ105 and BJ106 pedigrees are 67% and 33%, respectively. In particular, three of 10 affected matrilineal relatives of BJ105 pedigree had aminoglycoside-induced hearing loss, while seven affected matrilineal relatives in BJ105 pedigree and six affected matrilineal relatives in BJ106 pedigree did not have a history of exposure to aminoglycosides. Sequence analysis of the complete mitochondrial genomes in these pedigrees showed the identical homoplasmic A1555G mutation and distinct sets of mtDNA variants belonging to haplogroups F3 and M7b. These variants showed no evolutionary conservation, implying that mitochondrial haplotype may not play a significant role in the phenotypic expression of the A1555G mutation in these Chinese pedigrees. However, aminoglycosides and nuclear backgrounds appear to be major modifier factors for the phenotypic manifestation of the A1555G mutation in these Chinese families

  4. Glutathionylation of the Bacterial Hsp70 Chaperone DnaK Provides a Link between Oxidative Stress and the Heat Shock Response.

    Science.gov (United States)

    Zhang, Hong; Yang, Jie; Wu, Si; Gong, Weibin; Chen, Chang; Perrett, Sarah

    2016-03-25

    DnaK is the major bacterial Hsp70, participating in DNA replication, protein folding, and the stress response. DnaK cooperates with the Hsp40 co-chaperone DnaJ and the nucleotide exchange factor GrpE. Under non-stress conditions, DnaK binds to the heat shock transcription factor σ(32)and facilitates its degradation. Oxidative stress results in temporary inactivation of DnaK due to depletion of cellular ATP and thiol modifications such as glutathionylation until normal cellular ATP levels and a reducing environment are restored. However, the biological significance of DnaK glutathionylation remains unknown, and the mechanisms by which glutathionylation may regulate the activity of DnaK are also unclear. We investigated the conditions under which Escherichia coli DnaK undergoesS-glutathionylation. We observed glutathionylation of DnaK in lysates of E. coli cells that had been subjected to oxidative stress. We also obtained homogeneously glutathionylated DnaK using purified DnaK in the apo state. We found that glutathionylation of DnaK reversibly changes the secondary structure and tertiary conformation, leading to reduced nucleotide and peptide binding ability. The chaperone activity of DnaK was reversibly down-regulated by glutathionylation, accompanying the structural changes. We found that interaction of DnaK with DnaJ, GrpE, or σ(32)becomes weaker when DnaK is glutathionylated, and the interaction is restored upon deglutathionylation. This study confirms that glutathionylation down-regulates the functions of DnaK under oxidizing conditions, and this down-regulation may facilitate release of σ(32)from its interaction with DnaK, thus triggering the heat shock response. Such a mechanism provides a link between oxidative stress and the heat shock response in bacteria. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  5. Differential Targeting of Hsp70 Heat Shock Proteins HSPA6 and HSPA1A with Components of a Protein Disaggregation/Refolding Machine in Differentiated Human Neuronal Cells following Thermal Stress

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    Ian R. Brown

    2017-04-01

    Full Text Available Heat shock proteins (Hsps co-operate in multi-protein machines that counter protein misfolding and aggregation and involve DNAJ (Hsp40, HSPA (Hsp70, and HSPH (Hsp105α. The HSPA family is a multigene family composed of inducible and constitutively expressed members. Inducible HSPA6 (Hsp70B' is found in the human genome but not in the genomes of mouse and rat. To advance knowledge of this little studied HSPA member, the targeting of HSPA6 to stress-sensitive neuronal sites with components of a disaggregation/refolding machine was investigated following thermal stress. HSPA6 targeted the periphery of nuclear speckles (perispeckles that have been characterized as sites of transcription. However, HSPA6 did not co-localize at perispeckles with DNAJB1 (Hsp40-1 or HSPH1 (Hsp105α. At 3 h after heat shock, HSPA6 co-localized with these members of the disaggregation/refolding machine at the granular component (GC of the nucleolus. Inducible HSPA1A (Hsp70-1 and constitutively expressed HSPA8 (Hsc70 co-localized at nuclear speckles with components of the machine immediately after heat shock, and at the GC layer of the nucleolus at 1 h with DNAJA1 and BAG-1. These results suggest that HSPA6 exhibits targeting features that are not apparent for HSPA1A and HSPA8.

  6. Cytotoxicity and Expression of c-fos, HSP70, and GADD45/153 Proteins in Human Liver Carcinoma (HepG2 Cells Exposed to Dinitrotoluenes

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    Paul B. Tchounwou

    2005-08-01

    ŽÂ¼g/mL or within the dose range of 0-200 μg/mL for 2,6-DNT. The 45-kDa growth arrest and damage protein was significantly expressed at the dose range of 200 – 250μg/mL for 2,6-DNT and at the dose range of 200 - 400μg/mL for 2,4-DNT. Expression of 153-kDa growth arrest and DNA damage protein was significant at the 100, 200, and 250μg/mL doses for 2,6-DNT and at the 200 μg/mL dose for 2,4-DNT. Overall, these results indicate the potential of DNTs to induce cytotoxic, proteotoxic (HSP70, and genotoxic (GADD45/153 effects, as well as oxidative stress and pro-inflammatory reactions (c-fos.

  7. Heat-shock protein (Hsp70) and cytochrome P-450 (CYP1A) in the white mullet Mugil curema (Pisces:Mugilidae) as biomarkers to assess environmental quality in coastal lagoons.

    Science.gov (United States)

    Rios-Sicairos, Julian; Betancourt-Lozano, Miguel; Leal-Tarin, Beatriz; Hernandez-Cornejo, Rubi; Aguilar-Zarate, Gabriela; Garcia-De-La-Parra, Luz Maria; Gutierrez, Jesus N; Marquez-Rocha, Facundo; Garcia-Gasca, Alejandra

    2010-01-01

    Biomarkers have been useful tools to monitor some effects of pollution in coastal environments. Hepatic expression of heat-shock protein 70 (Hsp70) and cytochrome P450 1A (CYP1A) were analyzed in white mullet (Mugil curema) by RT-PCR from July, 2005 until July, 2006 in three coastal lagoons located in the southern Gulf of California, Mexico. These three coastal systems receive contaminants derived from local anthropogenic activities. Heat-shock proteins function to maintain protein integrity in the presence of stressors (such as heat or chemicals) and can be used as biomarkers of homeostatic alterations in polluted environments, whereas cytochrome P450 family members participate in steroid hormone synthesis and metabolism, and in xenobiotic transformation as a detoxification mechanism. The expression levels of both genes showed consistency in time and space, and presented a high overall correlation (r = 0.731, P < 0.001). Regardless of a high individual variability, both genes presented higher expression levels in the Urias Estuary (P < 0.001 and P < 0.05 for CYP1A and Hsp70, respectively), which was considered the most polluted among the three systems, especially during the rainy season (summer to fall). Gene expression levels were significantly associated with non-halogenated hydrocarbon concentrations in sediments during the sampling period (r = 0.686, P = 0.019 for CYP1A and r = 0.91, P < 0.001 for Hsp70), suggesting that both genes respond to chemicals in the environment. The results indicate that Mugil curema is a good candidate species to implement biomonitoring programs in tropical coastal environments.

  8. Late rise in hemolymph osmolality in Macrobrachium acanthurus (diadromous freshwater shrimp) exposed to brackish water: Early reduction in branchial Na+/K+ pump activity but stable muscle HSP70 expression.

    Science.gov (United States)

    Freire, Carolina A; Maraschi, Anieli C; Lara, Alessandra F; Amado, Enelise M; Prodocimo, Viviane

    2018-02-01

    Some Macrobrachium shrimps (Caridea, Palaemonidae) are diadromous; freshwater adults are truly euryhaline, while larvae need saline water for development. Branchial Na + /K + -ATPase (NKA) and carbonic anhydrase (CA) are involved in NaCl absorption in freshwater. This study aimed at verifying the time course of the osmoregulatory response of adult Macrobrachium acanthurus to high salinity brackish water (20‰), from the first 30min to 5days. The goal was to detect possible transition from hyper- to hyporegulation, the putative involvement of branchial NKA and CA, or the induction of muscular HSP70 expression. Hemolymph osmotic and ionic concentrations remained relatively stable and close to control levels until ~9h of exposure, but later increased consistently (~50%). A fast reduction in NKA activity (3-6h) was observed; these shrimps seem to shut off salt absorption already in the first hours. Later on, especially after 24h, hemolymph concentrations rise but HSP70 expression is not induced, possibly because constitutive levels are already sufficient to prevent protein damage. Time-dependent response mechanisms effective in high salinity brackish water, resulting in salt loading avoidance and suggestive of hyporegulation should be further investigated in decapods that evolutionary invaded freshwater. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. In Silico Molecular Modeling and Docking Studies on Novel Mutants (E229V, H225P and D230C) of the Nucleotide-Binding Domain of Homo sapiens Hsp70.

    Science.gov (United States)

    Elengoe, Asita; Hamdan, Salehhuddin

    2017-12-01

    In this study, we explored the possibility of determining the synergistic interactions between nucleotide-binding domain (NBD) of Homo sapiens heat-shock 70 kDa protein (Hsp70) and E1A 32 kDa of adenovirus serotype 5 motif (PNLVP) in the efficiency of killing of tumor cells in cancer treatment. At present, the protein interaction between NBD and PNLVP motif is still unknown, but believed to enhance the rate of virus replication in tumor cells. Three mutant models (E229V, H225P and D230C) were built and simulated, and their interactions with PNLVP motif were studied. The PNLVP motif showed the binding energy and intermolecular energy values with the novel E229V mutant at -7.32 and -11.2 kcal/mol. The E229V mutant had the highest number of hydrogen bonds (7). Based on the root mean square deviation, root mean square fluctuation, hydrogen bonds, salt bridge, secondary structure, surface-accessible solvent area, potential energy and distance matrices analyses, it was proved that the E229V had the strongest and most stable interaction with the PNLVP motif among all the four protein-ligand complex structures. The knowledge of this protein-ligand complex model would help in designing Hsp70 structure-based drug for cancer therapy.

  10. Clinical and molecular analysis of a four-generation Chinese family with aminoglycoside-induced and nonsyndromic hearing loss associated with the mitochondrial 12S rRNA C1494T mutation

    International Nuclear Information System (INIS)

    Wang Qiuju; Li Qingzhong; Han Dongyi; Zhao Yali; Zhao Lidong; Qian Yaping; Yuan Hu; Li Ronghua; Zhai Suoqiang; Young Wieyen; Guan Minxin

    2006-01-01

    We report here the clinical, genetic, and molecular characterization of a four-generation Chinese family with aminoglycoside-induced and nonsyndromic hearing loss. Five of nine matrilineal relatives had aminoglycoside-induced hearing loss. These matrilineal relatives exhibited variable severity and audiometric configuration of hearing impairment, despite sharing some common features: being bilateral and having sensorineural hearing impairment. Sequence analysis of mitochondrial DNA (mtDNA) in the pedigree identified 16 variants and the homoplasmic 12S rRNA C1494T mutation, which was associated with hearing loss in the other large Chinese family. In fact, the occurrence of the C1494T mutation in these genetically unrelated pedigrees affected by hearing impairment strongly indicated that this mutation is involved in the pathogenesis of aminoglycoside-induced and nonsyndromic hearing loss. However, incomplete penetrance of hearing loss indicated that the C1494T mutation itself is not sufficient to produce a clinical phenotype but requires the involvement of modifier factors for the phenotypic expression. Those mtDNA variants, showing no evolutional conservation, may not have a potential modifying role in the pathogenesis of the C1494T mutation. However, nuclear background seems to contribute to the phenotypic variability of matrilineal relatives in this family. Furthermore, aminoglycosides modulate the expressivity and penetrance of deafness associated with the C1494T mutation in this family

  11. Inhibiting Heat-Shock Protein 90 Reverses Sensory Hypoalgesia in Diabetic Mice

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    Michael J Urban

    2010-07-01

    Full Text Available Increasing the expression of Hsp70 (heat-shock protein 70 can inhibit sensory neuron degeneration after axotomy. Since the onset of DPN (diabetic peripheral neuropathy is associated with the gradual decline of sensory neuron function, we evaluated whether increasing Hsp70 was sufficient to improve several indices of neuronal function. Hsp90 is the master regulator of the heat-shock response and its inhibition can up-regulate Hsp70. KU-32 (N-{7-[(2R, 3R, 4S, 5R-3, 4-dihydroxy-5-methoxy-6, 6-dimethyl-tetrahydro-2H-pyran-2-yloxy]-8-methyl-2-oxo-2H-chromen-3-yl}acetamide was developed as a novel, novobiocin-based, C-terminal inhibitor of Hsp90 whose ability to increase Hsp70 expression is linked to the presence of an acetamide substitution of the prenylated benzamide moiety of novobiocin. KU-32 protected against glucose-induced death of embryonic DRG (dorsal root ganglia neurons cultured for 3 days in vitro. Similarly, KU-32 significantly decreased neuregulin 1-induced degeneration of myelinated Schwann cell DRG neuron co-cultures prepared from WT (wild-type mice. This protection was lost if the co-cultures were prepared from Hsp70.1 and Hsp70.3 KO (knockout mice. KU-32 is readily bioavailable and was administered once a week for 6 weeks at a dose of 20 mg/kg to WT and Hsp70 KO mice that had been rendered diabetic with streptozotocin for 12 weeks. After 12 weeks of diabetes, both WT and Hsp70 KO mice developed deficits in NCV (nerve conduction velocity and a sensory hypoalgesia. Although KU-32 did not improve glucose levels, HbA1c (glycated haemoglobin or insulin levels, it reversed the NCV and sensory deficits in WT but not Hsp70 KO mice. These studies provide the first evidence that targeting molecular chaperones reverses the sensory hypoalgesia associated with DPN.

  12. Caracterización in silico de las proteínas del choque térmico Hsp70 y Hsp90 deBemisia tabaci (Hemiptera: Aleyrodidae y su posible actividad adaptativa

    Directory of Open Access Journals (Sweden)

    Eneida Torres Cabra

    2014-06-01

    Full Text Available La mosca blanca, Bemisia tabaci (Hemiptera: Aleyrodidae es una de las plagas más destructivas e invasivas en el mundo, ataca una gran cantidad de cultivos. Se adapta fácilmente a plantas hospederas y a nuevas regiones geográficas, lo que sugiere el desarrollo de mecanismos de control a daños producidos por factores estresantes. Las proteínas Hsp se expresanen los organismos como mecanismo de defensa, actúan como chaperonas en el correcto ensamblaje de las proteínas. En este estudio se realizó una caracterizaciónin silico de las proteínas Hsp70 y Hsp90 de B. tabaci, secuencias obtenidas de NCBI. La determinaciónde los perfiles de hidrofobicidad, polaridad, accesibilidady flexibilidad se obtuvieron con “ProScale” de ExPASy, el perfil de antigenicidad con JaMBW. La secuencia aminoacídica se analizó con GOR IV y SOPMA y la composición de aminoácidos con ProtParam. Para analizar el peso molecular, índice deinestabilidad, índice alifático y gradiente hidropático,con GRAVY. La estructura terciaria se obtuvo con HHpred, y ESyPred3D. Para validar las estructuras 3D se utilizó Procheck, What_check y errat. Hsp70 y Hsp90 de B. tabaci presentan valores bajos de hidrofobicidady altos de polaridad, flexibilidad y accesibilidad, características que le permiten a las proteínas extender su capacidad como chaperonas. La Hsp70tiene una estructura secundaria compuesta por 41-45% alfa hélices, 30-43% coil y menos del 6% en hoja plegada y la Hsp90 por 52 y 53% hélices, 26-34% coily 6% hoja plegada. Las Hsp juegan un rol importante en los insectos debido a su tamaño y corto ciclo de vida, pues la temperatura influye en su distribución y abundancia.

  13. Metabolic fates and effects of nitrite in brown trout under normoxic and hypoxic conditions: blood and tissue nitrite metabolism and interactions with branchial NOS, Na+/K+-ATPase and hsp70 expression

    DEFF Research Database (Denmark)

    Jensen, Frank Bo; Gerber, Lucie; Hansen, Marie Niemann

    2015-01-01

    were higher in hypoxia than normoxia, suggesting increased NOS activity. Nitrite exposure strongly elevated nitrite concentrations in plasma, erythrocytes, heart tissue and white muscle, which was associated with an extensive metabolism of nitrite to nitrate and to iron-nitrosylated and S......Nitrite secures essential nitric oxide (NO) bioavailability in hypoxia at low endogenous concentrations, whereas it becomes toxic at high concentrations. We exposed brown trout to normoxic and hypoxic water in the absence and presence of added ambient nitrite to decipher the cellular metabolism...... and effects of nitrite at basal and elevated concentrations under different oxygen regimes. We also tested hypotheses concerning the influence of nitrite on branchial nitric oxide synthase (NOS), Na+/K+-ATPase (nka) and heat shock protein (hsp70) mRNA expression. Basal plasma and erythrocyte nitrite levels...

  14. 热应激大鼠心脏损伤与血淋巴细胞热休克蛋白70的关系%Relationship between heat stress-induced cardiomyocyte injury and HSP70 in lymphocytes in rats

    Institute of Scientific and Technical Information of China (English)

    井然; 钱捷; 弓景波; 梅竹松; 王新兴; 钱令嘉

    2012-01-01

    目的 观察不同高温环境中热应激大鼠心肌损伤状况,探索血液淋巴细胞中HSP70水平与心肌损伤的相关性规律及其意义.方法 50只雄性Wistar大鼠随机分为常温(22~25℃)组,36、37、38、39 cC热应激组.以人工高温舱对大鼠进行热暴露.采用电子肛温计检测大鼠肛温,采用八导生理记录仪观测大鼠心电图的变化,采用酶学试剂盒检测大鼠血清乳酸脱氢酶(LDH)和肌酸激酶同工酶(CK-MB)活力,采用Western Blot方法对大鼠外周血淋巴细胞热休克蛋白70(HSP70)含量进行半定量分析.结果 与常温组比较,36~39℃组体温均升高(均P<0.05);37~39℃组Q-T间期延长和R波振幅下降(均P<0.05);38~39℃组血清中LDH和CK-MB活力升高(均P<0.05).淋巴细胞中HSP70表达水平随环境温度的变化呈现不同的变化规律,热环境温度≤37℃时,HSP70表达随气温升高而显著增加(均P<0.05),热环境温度≥38℃后,HSP70表达随气温升高而下降,但仍显著高于常温组(均P<0.05).结论 热应激可导致大鼠心肌损伤和外周血淋巴细胞HSP70表达水平发生规律性变化,提示HSP70可能是热应激致心肌损伤的一种生物标志分子,在高温所致心肌损伤发生中具有重要作用.%Objective To investigate the myocardium damage of rats induced by hot environment and its correlation with HSP70 level in blood lymphocytes. Methods Fifty Wistar rats were randomly devided into one normal temperature group and four heat stress groups (36, 37, 38, 39 ℃). The artificial chamber with high temperature was used to establish the hot environment for rats. Rectal temperature of rats was detected by electronic thermograph. The electrocardiogram was examined by eight -channel physiological recorder. The activity of LDH and CK -MB were determined with biochemical methods. The expression level of HSP70 in blood lymphocytes was analyzed by Western Blot Results Compared with normal temperature

  15. Coexistence of mitochondrial 12S rRNA C1494T and CO1/tRNASer(UCN) G7444A mutations in two Han Chinese pedigrees with aminoglycoside-induced and non-syndromic hearing loss

    International Nuclear Information System (INIS)

    Yuan Huijun; Chen Jing; Liu Xin; Cheng Jing; Wang Xinjian; Yang Li; Yang Shuzhi; Cao Juyang; Kang Dongyang; Dai Pu; Zha, Suoqiang; Han Dongyi; Young Wieyen; Guan Minxin

    2007-01-01

    Mutations in mitochondrial DNA are one of the important causes of hearing loss. We report here the clinical, genetic, and molecular characterization of two Han Chinese pedigrees with maternally transmitted aminoglycoside-induced and nonsyndromic bilateral hearing loss. Clinical evaluation revealed the wide range of severity, age-at-onset, and audiometric configuration of hearing impairment in matrilineal relatives in these families. The penetrances of hearing loss in these pedigrees were 20% and 18%, when aminoglycoside-induced deafness was included. When the effect of aminoglycosides was excluded, the penetrances of hearing loss in these seven pedigrees were 10% and 15%. Sequence analysis of the complete mitochondrial genomes in these pedigrees showed the presence of the deafness-associated 12S rRNA C1494T and CO1/tRNA Ser(UCN) G7444A mutations. Their distinct sets of mtDNA polymorphism belonged to Eastern Asian haplogroup C4a1, while other previously identified six Chinese mitochondrial genomes harboring the C1494T mutation belong to haplogroups D5a2, D, R, and F1, respectively. This suggested that the C1494T or G7444A mutation occurred sporadically and multiplied through evolution of the mitochondrial DNA (mtDNA). The absence of functionally significant mutations in tRNA and rRNAs or secondary LHON mutations in their mtDNA suggest that these mtDNA haplogroup-specific variants may not play an important role in the phenotypic expression of the 12S rRNA C1494T and CO1/tRNA Ser(UCN) G7444A mutations in those Chinese families. However, aminoglycosides and other nuclear modifier genes play a modifying role in the phenotypic manifestation of the C1494T mutation in these Chinese families

  16. Influence of In Vitro IL-2 or IL-15 Alone or in Combination with Hsp 70 Derived 14-Mer Peptide (TKD on the Expression of NK Cell Activatory and Inhibitory Receptors on Peripheral Blood T Cells, B Cells and NKT Cells.

    Directory of Open Access Journals (Sweden)

    Ilona Hromadnikova

    Full Text Available Previous studies from Multhoff and colleagues reported that plasma membrane Hsp70 acts as a tumour-specific recognition structure for activated NK cells, and that the incubation of NK cells with Hsp70 and/or a 14-mer peptide derived from the N-terminal sequence of Hsp70 (TKDNNLLGRFELSG, TKD, aa 450-463 plus a low dose of IL-2 triggers NK cell proliferation and migration, and their capacity to kill cancer cells expressing membrane Hsp70. Herein, we have used flow cytometry to determine the influence of in vitro stimulation of peripheral blood mononuclear cells from healthy individuals with IL-2 or IL-15, either alone or in combination with TKD peptide on the cell surface expression of CD94, NK cell activatory receptors (CD16, NK2D, NKG2C, NKp30, NKp44, NKp46, NKp80, KIR2DL4, DNAM-1 and LAMP1 and NK cell inhibitory receptors (NKG2A, KIR2DL2/L3, LIR1/ILT-2 and NKR-P1A by CD3+CD56+ (NKT, CD3+CD4+, CD3+CD8+ and CD19+ populations. NKG2D, DNAM-1, LAMP1 and NKR-P1A expression was upregulated after the stimulation with IL-2 or IL-15 alone or in combination with TKD in NKT, CD8+ T cells and B cells. CD94 was upregulated in NKT and CD8+ T cells. Concurrently, an increase in a number of CD8+ T cells expressing LIR1/ILT-2 and CD4+ T cells positive for NKR-P1A was observed. The proportion of CD8+ T cells that expressed NKG2D was higher after IL-2/TKD treatment, when compared with IL-2 treatment alone. In comparison with IL-15 alone, IL-15/TKD treatment increased the proportion of NKT cells that were positive for CD94, LAMP1 and NKRP-1A. The more potent effect of IL-15/TKD on cell surface expression of NKG2D, LIR1/ILT-2 and NKRP-1A was observed in B cells compared with IL-15 alone. However, this increase was not of statistical significance. IL-2/TKD induced significant upregulation of LAMP1 in CD8+ T cells compared with IL-2 alone. Besides NK cells, other immunocompetent cells present within the fraction of peripheral blood mononuclear cells were influenced by

  17. Influence of In Vitro IL-2 or IL-15 Alone or in Combination with Hsp 70 Derived 14-Mer Peptide (TKD) on the Expression of NK Cell Activatory and Inhibitory Receptors on Peripheral Blood T Cells, B Cells and NKT Cells

    Science.gov (United States)

    Hromadnikova, Ilona; Li, Shuang; Kotlabova, Katerina; Dickinson, Anne M.

    2016-01-01

    Previous studies from Multhoff and colleagues reported that plasma membrane Hsp70 acts as a tumour-specific recognition structure for activated NK cells, and that the incubation of NK cells with Hsp70 and/or a 14-mer peptide derived from the N-terminal sequence of Hsp70 (TKDNNLLGRFELSG, TKD, aa 450–463) plus a low dose of IL-2 triggers NK cell proliferation and migration, and their capacity to kill cancer cells expressing membrane Hsp70. Herein, we have used flow cytometry to determine the influence of in vitro stimulation of peripheral blood mononuclear cells from healthy individuals with IL-2 or IL-15, either alone or in combination with TKD peptide on the cell surface expression of CD94, NK cell activatory receptors (CD16, NK2D, NKG2C, NKp30, NKp44, NKp46, NKp80, KIR2DL4, DNAM-1 and LAMP1) and NK cell inhibitory receptors (NKG2A, KIR2DL2/L3, LIR1/ILT-2 and NKR-P1A) by CD3+CD56+ (NKT), CD3+CD4+, CD3+CD8+ and CD19+ populations. NKG2D, DNAM-1, LAMP1 and NKR-P1A expression was upregulated after the stimulation with IL-2 or IL-15 alone or in combination with TKD in NKT, CD8+ T cells and B cells. CD94 was upregulated in NKT and CD8+ T cells. Concurrently, an increase in a number of CD8+ T cells expressing LIR1/ILT-2 and CD4+ T cells positive for NKR-P1A was observed. The proportion of CD8+ T cells that expressed NKG2D was higher after IL-2/TKD treatment, when compared with IL-2 treatment alone. In comparison with IL-15 alone, IL-15/TKD treatment increased the proportion of NKT cells that were positive for CD94, LAMP1 and NKRP-1A. The more potent effect of IL-15/TKD on cell surface expression of NKG2D, LIR1/ILT-2 and NKRP-1A was observed in B cells compared with IL-15 alone. However, this increase was not of statistical significance. IL-2/TKD induced significant upregulation of LAMP1 in CD8+ T cells compared with IL-2 alone. Besides NK cells, other immunocompetent cells present within the fraction of peripheral blood mononuclear cells were influenced by the treatment

  18. Introgression of heat shock protein (Hsp70 and sHsp) genes into the Malaysian elite chilli variety Kulai (Capsicum annuum L.) through the application of marker-assisted backcrossing (MAB).

    Science.gov (United States)

    Usman, Magaji G; Rafii, Mohd Y; Martini, Mohammad Y; Yusuff, Oladosu A; Ismail, Mohd R; Miah, Gous

    2018-03-01

    Backcrossing together with simple sequence repeat marker strategy was adopted to improve popular Malaysian chilli Kulai (Capsicum annuum L.) for heat tolerance. The use of molecular markers in backcross breeding and selection contributes significantly to overcoming the main drawbacks such as increase linkage drag and time consumption, in the ancient manual breeding approach (conventional), and speeds up the genome recovery of the recurrent parent. The strategy was adopted to introgress heat shock protein gene(s) from AVPP0702 (C. annuum L.), which are heat-tolerant, into the genetic profile of Kulai, a popular high-yielding chilli but which is heat sensitive. The parents were grown on seed trays, and parental screening was carried out with 252 simple sequence repeat markers. The selected parents were crossed and backcrossed to generate F 1 hybrids and backcross generations. Sixty-eight markers appeared to be polymorphic and were used to assess the backcross generation; BC 1 F 1 , BC 2 F 1 and BC 3 F 1 . The average recipient allele of the selected four BC 1 F 1 plants was 80.75% which were used to produce the BC 2 F 1 generation. BC 1 -P 7 was the best BC 1 F 1 plant because it had the highest recovery at 83.40% and was positive to Hsp-linked markers (Hsp70-u2 and AGi42). After three successive generations of backcrossing, the average genome recovery of the recurrent parent in the selected plants in BC 3 F 1 was 95.37%. Hsp gene expression analysis was carried out on BC 1 F 1 , BC 2 F 1 and BC 3 F 1 selected lines. The Hsp genes were found to be up-regulated when exposed to heat treatment. The pattern of Hsp expression in the backcross generations was similar to that of the donor parent. This confirms the successful introgression of a stress-responsive gene (Hsp) into a Kulai chilli pepper variety. Furthermore, the yield performance viz. plant height, number of fruits, fruit length and weight and total yield of the improved plant were similar with the recurrent

  19. Aminoglycoside-induced and non-syndromic hearing loss is associated with the G7444A mutation in the mitochondrial COI/tRNASer(UCN) genes in two Chinese families

    International Nuclear Information System (INIS)

    Zhu Yi; Qian Yaping; Tang Xiaowen; Wang Jindan; Yang Li; Liao Zhisu; Li Ronghua; Ji Jinzhang; Li Zhiyuan; Chen Jianfu; Choo, Daniel I.; Lu Jianxin; Guan Minxin

    2006-01-01

    We report here the clinical, genetic, and molecular characterization of two Chinese families with aminoglycoside induced and non-syndromic hearing impairment. Clinical and genetic evaluations revealed the variable severity and age-of-onset in hearing impairment in these families. Strikingly, there were extremely low penetrances of hearing impairment in these Chinese families. Sequence analysis of the complete mitochondrial genomes in these pedigrees showed the distinct sets of mtDNA polymorphism, in addition to the identical G7444A mutation associated with hearing loss. Indeed, the G7444A mutation in the CO1 gene and the precursor of tRNA Ser(UCN) gene is present in homoplasmy only in the maternal lineage of those pedigrees but not other members of these families and 164 Chinese controls. Their mitochondrial genomes belong to the Eastern Asian haplogroups C5a and D4a, respectively. In fact, the occurrence of the G7444A mutation in these several genetically unrelated subjects affected by hearing impairment strongly indicates that this mutation is involved in the pathogenesis of hearing impairment. However, there was the absence of other functionally significant mtDNA mutations in two Chinese pedigrees carrying the G7444A mutation. Therefore, nuclear modifier gene(s) or aminoglycoside(s) may play a role in the phenotypic expression of the deafness-associated G7444A mutation in these Chinese pedigrees

  20. Aminoglycoside induced ototoxicity associated with mitochondrial ...

    African Journals Online (AJOL)

    Joseph Foster II

    2016-06-16

    Jun 16, 2016 ... while current methods to mitigate the risk of ototoxic injury are in various stages of ... of preemptive audiometry provides the most readily available method to ..... current characterization of the MET channel has already led.

  1. Carvacrol Induces Heat Shock Protein 60 and Inhibits Synthesis of Flagellin in Escherichia coli O157:H7▿

    Science.gov (United States)

    Burt, Sara A.; van der Zee, Ruurd; Koets, Ad P.; de Graaff, Anko M.; van Knapen, Frans; Gaastra, Wim; Haagsman, Henk P.; Veldhuizen, Edwin J. A.

    2007-01-01

    The essential oils of oregano and thyme are active against a number of food-borne pathogens, such as Escherichia coli O157:H7. Carvacrol is one of the major antibacterial components of these oils, and p-cymene is thought to be its precursor in the plant. The effects of carvacrol and p-cymene on protein synthesis in E. coli O157:H7 ATCC 43895 cells were investigated. Bacteria were grown overnight in Mueller-Hinton broth with a sublethal concentration of carvacrol or p-cymene, and their protein compositions were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and confirmed by Western blotting. The presence of 1 mM carvacrol during overnight incubation caused E. coli O157:H7 to produce significant amounts of heat shock protein 60 (HSP60) (GroEL) (P < 0.05) and inhibited the synthesis of flagellin highly significantly (P < 0.001), causing cells to be aflagellate and therefore nonmotile. The amounts of HSP70 (DnaK) were not significantly affected. p-Cymene at 1 mM or 10 mM did not induce HSP60 or HSP70 in significant amounts and did not have a significant effect on flagellar synthesis. Neither carvacrol (0.3, 0.5, 0.8, or 1 mM) nor p-cymene (0.3, 0.5, or 0.8 mM) treatment of cells in the mid-exponential growth phase induced significant amounts of HSP60 or HSP70 within 3 h, although numerical increases of HSP60 were observed. Motility decreased with increasing concentrations of both compounds, but existing flagella were not shed. This study is the first to demonstrate that essential oil components induce HSP60 in bacteria and that overnight incubation with carvacrol prevents the development of flagella in E. coli O157:H7. PMID:17526792

  2. Coniferyl aldehyde attenuates radiation enteropathy by inhibiting cell death and promoting endothelial cell function.

    Science.gov (United States)

    Jeong, Ye-Ji; Jung, Myung Gu; Son, Yeonghoon; Jang, Jun-Ho; Lee, Yoon-Jin; Kim, Sung-Ho; Ko, Young-Gyo; Lee, Yun-Sil; Lee, Hae-June

    2015-01-01

    Radiation enteropathy is a common complication in cancer patients. The aim of this study was to investigate whether radiation-induced intestinal injury could be alleviated by coniferyl aldehyde (CA), an HSF1-inducing agent that increases cellular HSP70 expression. We systemically administered CA to mice with radiation enteropathy following abdominal irradiation (IR) to demonstrate the protective effects of CA against radiation-induced gastrointestinal injury. CA clearly alleviated acute radiation-induced intestinal damage, as reflected by the histopathological data and it also attenuated sub-acute enteritis. CA prevented intestinal crypt cell death and protected the microvasculature in the lamina propria during the acute and sub-acute phases of damage. CA induced HSF1 and HSP70 expression in both intestinal epithelial cells and endothelial cells in vitro. Additionally, CA protected against not only the apoptotic cell death of both endothelial and epithelial cells but also the loss of endothelial cell function following IR, indicating that CA has beneficial effects on the intestine. Our results provide novel insight into the effects of CA and suggest its role as a therapeutic candidate for radiation-induced enteropathy due to its ability to promote rapid re-proliferation of the intestinal epithelium by the synergic effects of the inhibition of cell death and the promotion of endothelial cell function.

  3. Responses of growth inhibition and antioxidant gene expression in earthworms (Eisenia fetida) exposed to tetrabromobisphenol A, hexabromocyclododecane and decabromodiphenyl ether.

    Science.gov (United States)

    Shi, Ya-juan; Xu, Xiang-bo; Zheng, Xiao-qi; Lu, Yong-long

    2015-01-01

    Tetrabromobisphenol A (TBBPA), hexabromocyclododecane (HBCD) and decabromodiphenyl ether (BDE 209), suspected ubiquitous contaminants, account for the largest volume of brominated flame retardants (BFRs) since penta-BDE and octa-BDE have been phased out globally. In this paper, the growth inhibition and gene transcript levels of antioxidant enzymes (superoxide dismutase (SOD), catalase (CAT)) and the stress-response gene involved in the prevention of oxidative stress (Hsp70) of earthworms (Eisenia fetida) exposed to TBBPA, HBCD and BDE 209 were measured to identify the toxicity effects of selected BFRs on earthworms. The growth of earthworms treated by TBBPA at 200 and 400 mg/kg dw were inhibited at rate of 13.7% and 22.0% respectively, while there was no significant growth inhibition by HBCD and BDE 209. A significant (Pearthworms exposed to TBBPA at 50 mg/kg dw (1.77-fold) and to HBCD at 400 mg/kg dw (2.06-fold). The transcript level of Hsp70 gene was significantly up-regulated (Pearthworms exposed to TBBPA at concentration of 50-200 mg/kg (2.16-2.19-fold) and HBCD at 400 mg/kg (2.61-fold). No significant variation of CAT gene expression in all the BFRs treatments was observed, neither does all the target gene expression level exposed to BDE 209. Assessed by growth inhibition and the changes at mRNA levels of encoding genes in earthworms, TBBPA showed the greatest toxicity, followed by HBCD and BDE 209, consistent with trends in molecular properties. The results help to understand the molecular mechanism of antioxidant defense. Copyright © 2015 Elsevier Inc. All rights reserved.

  4. The histone deacetylase inhibitor, Vorinostat, represses hypoxia inducible factor 1 alpha expression through translational inhibition.

    Directory of Open Access Journals (Sweden)

    Darren M Hutt

    Full Text Available Hypoxia inducible factor 1α (HIF-1α is a master regulator of tumor angiogenesis being one of the major targets for cancer therapy. Previous studies have shown that Histone Deacetylase Inhibitors (HDACi block tumor angiogenesis through the inhibition of HIF-1α expression. As such, Vorinostat (Suberoylanilide Hydroxamic Acid/SAHA and Romidepsin, two HDACis, were recently approved by the Food and Drug Administration (FDA for the treatment of cutaneous T cell lymphoma. Although HDACis have been shown to affect HIF-1α expression by modulating its interactions with the Hsp70/Hsp90 chaperone axis or its acetylation status, the molecular mechanisms by which HDACis inhibit HIF-1α expression need to be further characterized. Here, we report that the FDA-approved HDACi Vorinostat/SAHA inhibits HIF-1α expression in liver cancer-derived cell lines, by a new mechanism independent of p53, prolyl-hydroxylases, autophagy and proteasome degradation. We found that SAHA or silencing of HDAC9 mechanism of action is due to inhibition of HIF-1α translation, which in turn, is mediated by the eukaryotic translation initiation factor--eIF3G. We also highlighted that HIF-1α translation is dramatically inhibited when SAHA is combined with eIF3H silencing. Taken together, we show that HDAC activity regulates HIF-1α translation, with HDACis such as SAHA representing a potential novel approach for the treatment of hepatocellular carcinoma.

  5. LHCSR Expression under HSP70/RBCS2 Promoter as a Strategy to Increase Productivity in Microalgae

    OpenAIRE

    Perozeni, Federico; Stella, Giulio Rocco; Ballottari, Matteo

    2018-01-01

    Microalgae are unicellular photosynthetic organisms considered as potential alternative sources for biomass, biofuels or high value products. However, limited biomass productivity is commonly experienced in their cultivating system despite their high potential. One of the reasons for this limitation is the high thermal dissipation of the light absorbed by the outer layers of the cultures exposed to high light caused by the activation of a photoprotective mechanism called non-photochemical que...

  6. LHCSR Expression under HSP70/RBCS2 Promoter as a Strategy to Increase Productivity in Microalgae

    Directory of Open Access Journals (Sweden)

    Federico Perozeni

    2018-01-01

    Full Text Available Microalgae are unicellular photosynthetic organisms considered as potential alternative sources for biomass, biofuels or high value products. However, limited biomass productivity is commonly experienced in their cultivating system despite their high potential. One of the reasons for this limitation is the high thermal dissipation of the light absorbed by the outer layers of the cultures exposed to high light caused by the activation of a photoprotective mechanism called non-photochemical quenching (NPQ. In the model organism for green algae Chlamydomonas reinhardtii, NPQ is triggered by pigment binding proteins called light-harvesting-complexes-stress-related (LHCSRs, which are over-accumulated in high light. It was recently reported that biomass productivity can be increased both in microalgae and higher plants by properly tuning NPQ induction. In this work increased light use efficiency is reported by introducing in C. reinhardtii a LHCSR3 gene under the control of Heat Shock Protein 70/RUBISCO small chain 2 promoter in a npq4 lhcsr1 background, a mutant strain knockout for all LHCSR genes. This complementation strategy leads to a low expression of LHCSR3, causing a strong reduction of NPQ induction but is still capable of protecting from photodamage at high irradiance, resulting in an improved photosynthetic efficiency and higher biomass accumulation.

  7. [Potential protective role of nitric oxide and Hsp70 linked to functional foods in the atherosclerosis].

    Science.gov (United States)

    Camargo, Alejandra B; Manucha, Walter

    Atherosclerosis, one of the main pathologic entities considered epidemic and a worldwide public health problem, is currently under constant review as regards its basic determining mechanisms and therapeutic possibilities. In this regard, all patients afflicted with the disease exhibit mitochondrial dysfunction, oxidative stress and inflammation. Interestingly, nitric oxide - a known vasoactive messenger gas - has been closely related to the inflammatory, oxidative and mitochondrial dysfunctional process that characterizes atherosclerosis. In addition, it has recently been demonstrated that alterations in the bioavailability of nitric oxide would induce the expression of heat shock proteins. This agrees with the use of functional foods as a strategy to prevent both vascular aging and the development of atherosclerosis. Finally, a greater knowledge regarding the mechanisms implied in the development of atherosclerosis will enable proposing new and possible hygiene, health and therapeutic interventions. Copyright © 2016 Sociedad Española de Arteriosclerosis. Publicado por Elsevier España, S.L.U. All rights reserved.

  8. LHCSR Expression under HSP70/RBCS2 Promoter as a Strategy to Increase Productivity in Microalgae.

    Science.gov (United States)

    Perozeni, Federico; Stella, Giulio Rocco; Ballottari, Matteo

    2018-01-05

    Microalgae are unicellular photosynthetic organisms considered as potential alternative sources for biomass, biofuels or high value products. However, limited biomass productivity is commonly experienced in their cultivating system despite their high potential. One of the reasons for this limitation is the high thermal dissipation of the light absorbed by the outer layers of the cultures exposed to high light caused by the activation of a photoprotective mechanism called non-photochemical quenching (NPQ). In the model organism for green algae Chlamydomonas reinhardtii , NPQ is triggered by pigment binding proteins called light-harvesting-complexes-stress-related (LHCSRs), which are over-accumulated in high light. It was recently reported that biomass productivity can be increased both in microalgae and higher plants by properly tuning NPQ induction. In this work increased light use efficiency is reported by introducing in C. reinhardtii a LHCSR3 gene under the control of Heat Shock Protein 70 / RUBISCO small chain 2 promoter in a npq4 lhcsr1 background, a mutant strain knockout for all LHCSR genes. This complementation strategy leads to a low expression of LHCSR3 , causing a strong reduction of NPQ induction but is still capable of protecting from photodamage at high irradiance, resulting in an improved photosynthetic efficiency and higher biomass accumulation.

  9. Heat shock protein 70 inhibits shrinkage-induced programmed cell death via mechanisms independent of effects on cell volume-regulatory membrane transport proteins

    DEFF Research Database (Denmark)

    Nylandsted, J; Jäättelä, M; Hoffmann, E K

    2004-01-01

    Cell shrinkage is a ubiquitous feature of programmed cell death (PCD), but whether it is an obligatory signalling event in PCD is unclear. Heat shock protein 70 (Hsp70) potently counteracts PCD in many cells, by mechanisms that are incompletely understood. In the present investigation, we found...... that severe hypertonic stress greatly diminished the viability of murine fibrosarcoma cells (WEHI-902) and immortalized murine embryonic fibroblasts (iMEFs). This effect was attenuated markedly by Hsp70 over-expression. To determine whether the protective effect of Hsp70 was mediated via an effect on volume...... regulatory ion transport, we compared regulatory volume decrease (RVD) and increase (RVI) in control WEHI-902 cells and after increasing Hsp70 levels by heat shock or over-expression (WEHI-912). Hsp70 levels affected neither RVD, RVI nor the relative contributions of the Na(+)/H(+)-exchanger (NHE1) and Na...

  10. Ibuprofen enhances the anticancer activity of cisplatin in lung cancer cells by inhibiting the heat shock protein 70

    Science.gov (United States)

    Endo, H; Yano, M; Okumura, Y; Kido, H

    2014-01-01

    Hsp70 is often overexpressed in cancer cells, and the selective cellular survival advantage that it confers may contribute to the process of tumour formation. Thus, the pharmacological manipulation of Hsp70 levels in cancer cells may be an effective means of preventing the progression of tumours. We found that the downregulation of Hsp70 by ibuprofen in vitro enhances the antitumoural activity of cisplatin in lung cancer. Ibuprofen prominently suppressed the expression of Hsp70 in A549 cells derived from lung adenocarcinoma and sensitized them to cisplatin in association with an increase in the mitochondrial apoptotic cascade, whereas ibuprofen alone did not induce cell death. The cisplatin-dependent events occurring up- and downstream of mitochondrial disruption were accelerated by treatment with ibuprofen. The increase in cisplatin-induced apoptosis caused by the depletion of Hsp70 by RNA interference is evidence that the increased apoptosis by ibuprofen is mediated by its effect on Hsp70. Our observations indicate that the suppression of Hsp70 by ibuprofen mediates the sensitivity to cisplatin by enhancing apoptosis at several stages of the mitochondrial cascade. Ibuprofen, therefore, is a potential therapeutic agent that might allow lowering the doses of cisplatin and limiting the many challenge associated with its toxicity and development of drug resistance. PMID:24481441

  11. Suppression of heat shock protein 70 by siRNA enhances the antitumor effects of cisplatin in cultured human osteosarcoma cells.

    Science.gov (United States)

    Mori, Yuki; Terauchi, Ryu; Shirai, Toshiharu; Tsuchida, Shinji; Mizoshiri, Naoki; Arai, Yuji; Kishida, Tsunao; Fujiwara, Hiroyoshi; Mazda, Osam; Kubo, Toshikazu

    2017-09-01

    Although advances in chemotherapy have improved the prognosis for osteosarcoma, some patients do not respond sufficiently to treatment. Heat shock protein 70 (Hsp70) is expressed at high levels in cancer cells and attenuates the therapeutic efficacy of anticancer agents, resulting in a poorer prognosis. This study investigated whether small interfering RNA (siRNA)-mediated inhibition of Hsp70 expression in an osteosarcoma cell line would enhance sensitivity to cisplatin. The expression of Hsp70 with cisplatin treatment was observed by using Western blotting and real-time reverse transcription polymerase chain reaction (RT-PCR). Changes in the IC 50 of cisplatin when Hsp70 was inhibited by siRNA were evaluated. Cisplatin's effectiveness in inducing apoptosis was assessed by assay of terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL), caspase-3 activity, and mitochondrial membrane potential. Up-regulation of Hsp70 expression was dependent on the concentration of cisplatin. Inhibition of Hsp70 expression significantly reduced the IC 50 of cisplatin. When cisplatin was added to osteosarcoma cells with Hsp70 expression inhibited, a significant increase in apoptosis was demonstrated in TUNEL, caspase-3, and mitochondrial membrane potential assays. Inhibition of Hsp70 expression induced apoptosis in cultured osteosarcoma cells, indicating that Hsp70 inhibition enhanced sensitivity to cisplatin. Inhibition of Hsp70 expression may provide a new adjuvant therapy for osteosarcoma.

  12. Pu-erh Tea Inhibits Tumor Cell Growth by Down-Regulating Mutant p53

    Science.gov (United States)

    Zhao, Lanjun; Jia, Shuting; Tang, Wenru; Sheng, Jun; Luo, Ying

    2011-01-01

    Pu-erh tea is a kind of fermented tea with the incorporation of microorganisms’ metabolites. Unlike green tea, the chemical characteristics and bioactivities of Pu-erh tea are still not well understood. Using water extracts of Pu-erh tea, we analyzed the tumor cell growth inhibition activities on several genetically engineered mouse tumor cell lines. We found that at the concentration that did not affect wild type mouse embryo fibroblasts (MEFs) growth, Pu-erh tea extracts could inhibit tumor cell growth by down-regulated S phase and cause G1 or G2 arrest. Further study showed that Pu-erh tea extracts down-regulated the expression of mutant p53 in tumor cells at the protein level as well as mRNA level. The same concentration of Pu-erh tea solution did not cause p53 stabilization or activation of its downstream pathways in wild type cells. We also found that Pu-erh tea treatment could slightly down-regulate both HSP70 and HSP90 protein levels in tumor cells. These data revealed the action of Pu-erh tea on tumor cells and provided the possible mechanism for Pu-erh tea action, which explained its selectivity in inhibiting tumor cells without affecting wild type cells. Our data sheds light on the application of Pu-erh tea as an anti-tumor agent with low side effects. PMID:22174618

  13. Reduced Contractility and Motility of Prostatic Cancer-Associated Fibroblasts after Inhibition of Heat Shock Protein 90

    Directory of Open Access Journals (Sweden)

    Alex Henke

    2016-08-01

    Full Text Available Background: Prostate cancer-associated fibroblasts (CAF can stimulate malignant progression and invasion of prostatic tumour cells via several mechanisms including those active in extracellular matrix; Methods: We isolated CAF from prostate cancer patients of Gleason Score 6–10 and confirmed their cancer-promoting activity using an in vivo tumour reconstitution assay comprised of CAF and BPH1 cells. We tested the effects of heat shock protein 90 (HSP90 inhibitors upon reconstituted tumour growth in vivo. Additionally, CAF contractility was measured in a 3D collagen contraction assay and migration was measured by scratch assay; Results: HSP90 inhibitors dipalmitoyl-radicicol and 17-dimethylaminoethylamino-17-demethoxygeldanamycin (17-DMAG reduced tumour size and proliferation in CAF/BPH1 reconstituted tumours in vivo. We observed that the most contractile CAF were derived from patients with lower Gleason Score and of younger age compared with the least contractile CAF. HSP90 inhibitors radicicol and 17-DMAG inhibited contractility and reduced the migration of CAF in scratch assays. Intracellular levels of HSP70 and HSP90 were upregulated upon treatment with HSP90 inhibitors. Inhibition of HSP90 also led to a specific increase in transforming growth factor beta 2 (TGFβ2 levels in CAF; Conclusions: We suggest that HSP90 inhibitors act not only upon tumour cells, but also on CAF in the tumour microenvironment.

  14. Mitochondria-targeting nanomedicine: An effective and potent strategy against aminoglycosides-induced ototoxicity.

    Science.gov (United States)

    Zhou, Shuang; Sun, Yanhui; Kuang, Xiao; Hou, Shanshan; Yang, YinXian; Wang, Zhenjie; Liu, Hongzhuo

    2018-04-21

    We report a proof-of-concept for the development of mitochondria-targeting nanoparticles (NPs) loaded with geranylgeranylacetone (GGA) to protect against a wide range of gentamicin-induced ototoxicity symptoms in a zebrafish model. The polymeric NPs were functionalized with a mitochondrial-homing peptide (d‑Arg‑Dmt‑Orn‑Phe‑NH 2 ) and exhibited greater mitochondrial uptake and lower gentamicin uptake in hair cells via mechanotransduction (MET) channels and tuned machinery in the hair bundle than the ordinary NPs did. Blockade of MET channels rapidly reversed this effect, indicating the reversible responses of hair cells to the targeting NPs were mediated by MET channels. Pretreatment of hair cells with mitochondria-targeting GGA-loaded NPs exhibited a superior acute or chronic protective efficacy against subsequent exposure to gentamicin compared with unmodified formulations. Mitochondrial delivery regulating the death pathway of hair cells appeared to cause the therapeutic failure of untargeted NPs. Thus, peptide-directed mitochondria-targeting NPs may represent a novel therapeutic strategy for mitochondrial dysfunction-linked diseases. Copyright © 2018 Elsevier B.V. All rights reserved.

  15. Alanine Enhances Aminoglycosides-Induced ROS Production as Revealed by Proteomic Analysis

    Directory of Open Access Journals (Sweden)

    Jin-zhou Ye

    2018-01-01

    Full Text Available Metabolite-enabled killing of antibiotic-resistant pathogens by antibiotics is an attractive strategy to manage antibiotic resistance. Our previous study demonstrated that alanine or/and glucose increased the killing efficacy of kanamycin on antibiotic-resistant bacteria, whose action is through up-regulating TCA cycle, increasing proton motive force and enhancing antibiotic uptake. Despite the fact that alanine altered several metabolic pathways, other mechanisms could be potentially involved in alanine-mediated kanamycin killing of bacteria which remains to be explored. In the present study, we adopted proteomic approach to analyze the proteome changes induced by exogenous alanine. Our results revealed that the expression of three outer membrane proteins was altered and the deletion of nagE and fadL decreased the intracellular kanamycin concentration, implying their possible roles in mediating kanamycin transport. More importantly, the integrated analysis of proteomic and metabolomic data pointed out that alanine metabolism could connect to riboflavin metabolism that provides the source for reactive oxygen species (ROS production. Functional studies confirmed that alanine treatment together with kanamycin could promote ROS production that in turn potentiates the killing of antibiotic-resistant bacteria. Further investigation showed that alanine repressed the transcription of antioxidant-encoding genes, and alanine metabolism to riboflavin metabolism connected with riboflavin metabolism through TCA cycle, glucogenesis pathway and pentose phosphate pathway. Our results suggest a novel mechanism by which alanine facilitates kanamycin killing of antibiotic-resistant bacteria via promoting ROS production.

  16. Chaperonins fight aminoglycoside-induced protein misfolding and promote short-term tolerance in Escherichia coli

    DEFF Research Database (Denmark)

    Goltermann, Lise; Good, Liam; Bentin, Thomas

    2013-01-01

    For almost half of a century, we have known that aminoglycoside antibiotics corrupt ribosomes, causing translational misreading, yet it remains unclear whether or not misreading triggers protein misfolding, and possible effects of chaperone action on drug susceptibilities are poorly understood...

  17. Two unusual cases of severe recalcitrant hypocalcemia due to aminoglycoside-induced hypomagnesemia

    Directory of Open Access Journals (Sweden)

    Tarun Varma

    2013-01-01

    Full Text Available Aminoglycoside (AMG-induced renal toxicity is well-known and may manifest with non-oliguric renal failure or renal tubular dysfunction like Fanconi-like syndrome, Barter syndrome-like syndrome or distal renal tubular acidosis (RTA. These phenomena have been described with Gentamycin and Amikacin though rarely with Kanamycin. We present two cases of pulmonary tuberculosis that were treated with Kanamycin and during the course of treatment, developed severe recalcitrant hypocalcemia along with hypomagnesemia.

  18. Pure tone audiograms and possible aminoglycoside-induced hearing loss in belugas (Delphinapterus leucas)

    Science.gov (United States)

    Finneran, James J.; Carder, Donald A.; Dear, Randall; Belting, Traci; McBain, Jim; Dalton, Les; Ridgway, Sam H.

    2005-06-01

    A behavioral response paradigm was used to measure pure-tone hearing sensitivities in two belugas (Delphinapterus leucas). Tests were conducted over a 20-month period at the Point Defiance Zoo and Aquarium, in Tacoma, WA. Subjects were two males, aged 8-10 and 9-11 during the course of the study. Subjects were born in an oceanarium and had been housed together for all of their lives. Hearing thresholds were measured using a modified up/down staircase procedure and acoustic response paradigm where subjects were trained to produce audible responses to test tones and to remain quiet otherwise. Test frequencies ranged from approximately 2 to 130 kHz. Best sensitivities ranged from approximately 40 to 50 dB re 1 μPa at 50-80 kHz and 30-35 kHz for the two subjects. Although both subjects possessed traditional ``U-shaped'' mammalian audiograms, one subject exhibited significant high-frequency hearing loss above 37 kHz compared to previously published data for belugas. Hearing loss in this subject was estimated to approach 90 dB for frequencies above 50 kHz. Similar ages, ancestry, and environmental conditions between subjects, but a history of ototoxic drug administration in only one subject, suggest that the observed hearing loss was a result of the aminoglycoside antibiotic amikacin. .

  19. Novel Entropically Driven Conformation-specific Interactions with Tomm34 Protein Modulate Hsp70 Protein Folding and ATPase Activities

    Czech Academy of Sciences Publication Activity Database

    Durech, M.; Trčka, F.; Man, Petr; Blackburn, E.A.; Hernychová, L.; Dvořáková, P.; Coufalová, D.; Kavan, Daniel; Vojtěšek, B.; Muller, P.

    2016-01-01

    Roč. 15, č. 5 (2016), s. 1710-1727 ISSN 1535-9476 R&D Projects: GA MŠk(CZ) LO1509 EU Projects: Wellcome Trust(CZ) 01527/Z/13/Z Institutional support: RVO:61388971 Keywords : HEAT-SHOCK-PROTEIN * MOLECULAR CHAPERONE DNAK * SUBSTRATE-BINDING DOMAIN * INVASIVE BREAST - CANCER Subject RIV: CE - Biochemistry Impact factor: 6.540, year: 2016

  20. Interactions of p60, a mediator of progesterone receptor assembly, with heat shock proteins hsp90 and hsp70

    DEFF Research Database (Denmark)

    Chen, S; Prapapanich, V; Rimerman, R A

    1996-01-01

    Previous studies on the assembly of progesterone receptor (PR) complexes in vitro have suggested that PR assembly is a dynamic, ordered process involving at least eight nonreceptor proteins. One of these proteins, p60, appears transiently during assembly and is not a component of functionally...

  1. Vitamin A Oral Supplementation Induces Oxidative Stress and Suppresses IL-10 and HSP70 in Skeletal Muscle of Trained Rats

    Directory of Open Access Journals (Sweden)

    Lyvia Lintzmaier Petiz

    2017-04-01

    Full Text Available Exercise training intensity is the major variant that influences the relationship between exercise, redox balance, and immune response. Supplement intake is a common practice for oxidative stress prevention; the effects of vitamin A (VA on exercise training are not yet described, even though this molecule exhibits antioxidant properties. We investigated the role of VA supplementation on redox and immune responses of adult Wistar rats subjected to swimming training. Animals were divided into four groups: sedentary, sedentary + VA, exercise training, and exercise training + VA. Over eight weeks, animals were submitted to intense swimming 5 times/week and a VA daily intake of 450 retinol equivalents/day. VA impaired the total serum antioxidant capacity acquired by exercise, with no change in interleukin-1β and tumor necrosis factor-α levels. In skeletal muscle, VA caused lipid peroxidation and protein damage without differences in antioxidant enzyme activities; however, Western blot analysis showed that expression of superoxide dismutase-1 was downregulated, and upregulation of superoxide dismutase-2 induced by exercise was blunted by VA. Furthermore, VA supplementation decreased anti-inflammatory interleukin-10 and heat shock protein 70 expression, important factors for positive exercise adaptations and tissue damage prevention. Our data showed that VA supplementation did not confer any antioxidative and/or protective effects, attenuating exercise-acquired benefits in the skeletal muscle.

  2. The human HSP70/HSP40 chaperone family : a study on its capacity to combat proteotoxic stress

    NARCIS (Netherlands)

    Hageman, Jurre

    2008-01-01

    All cells are constantly threatened by both physical and chemical stress factors that can damage e.g. the DNA and proteins. Whereas the molecular mechanisms responsible for DNA repair have been studied in great detail, the mechanism underlying the repair and disposal of damaged proteins are far less

  3. Identification of cytosolic peroxisome proliferator binding protein as a member of the heat shock protein HSP70 family.

    OpenAIRE

    Alvares, K; Carrillo, A; Yuan, P M; Kawano, H; Morimoto, R I; Reddy, J K

    1990-01-01

    Clofibrate and many of its structural analogues induce proliferation of peroxisomes in the hepatic parenchymal cells of rodents and certain nonrodent species including primates. This induction is tissue specific, occurring mainly in the liver parenchymal cells and to a lesser extent in the kidney cortical epithelium. The induction of peroxisomes is associated with a predictable pleiotropic response, characterized by hepatomegaly, and increased activities and mRNA levels of certain peroxisomal...

  4. Hsp70 expression and metabolite composition in response to short-term thermal changes in Folsomia candida (Collembola)

    DEFF Research Database (Denmark)

    Waagner, Dorthe; Heckmann, Lars-Henrik; Malmendal, Anders

    2010-01-01

    In the present study the joint transcriptomic and metabolomic responses in Folsomia candida (Collembola) to temperature changes on a short-term scale were studied. Change in heat tolerance was examined as survival after a 35 degrees C heat shock (2h) in the course of either a fluctuating temperat......In the present study the joint transcriptomic and metabolomic responses in Folsomia candida (Collembola) to temperature changes on a short-term scale were studied. Change in heat tolerance was examined as survival after a 35 degrees C heat shock (2h) in the course of either a fluctuating...... analysed in F. candida using nuclear magnetic resonance spectroscopy ((1)H NMR). A significant metabolomic divergence between pre-treated and control collembolans was evident; partly due to a significantly reduced relative concentration of five free amino acids (arginine, leucine, lysine, phenylalanine...

  5. Anaplasma phagocytophilum MSP4 and HSP70 Proteins Are Involved in Interactions with Host Cells during Pathogen Infection

    Czech Academy of Sciences Publication Activity Database

    Contreras, M.; Alberdi, P.; Mateos-Hernández, L.; Fernández de Mera, I.G.; García-Pérez, A. L.; Vancová, Marie; Villar, M.; Ayllón, N.; Cabezas Cruz, Alejandro; Valdés, James J.; Stuen, S.; Gortazar, C.; de la Fuente, J.

    2017-01-01

    Roč. 7, JUL 5 (2017), č. článku 307. ISSN 2235-2988 EU Projects: European Commission(XE) 278976 - ANTIGONE Institutional support: RVO:60077344 Keywords : anaplasmosis * immunology * hl60 * tick * vaccine * sheep * Anaplasma phagocytophilum Subject RIV: EC - Immunology OBOR OECD: Immunology Impact factor: 4.300, year: 2016

  6. Mitochondrial Heat Shock Protein Machinery Hsp70/Hsp40 Is Indispensable for Proper Mitochondrial DNA Maintenance and Replication

    Czech Academy of Sciences Publication Activity Database

    Týč, Jiří; Klingbeil, M.M.; Lukeš, Julius

    2015-01-01

    Roč. 6, č. 1 (2015), e02425-14 ISSN 2150-7511 R&D Projects: GA MŠk LH12104; GA MŠk(CZ) EE2.3.30.0032; GA ČR GAP305/12/2261 EU Projects: European Commission(XE) 316304 Institutional support: RVO:60077344 Keywords : procyclic Trypanosoma brucei * transfer RNA import * kinetoplast DNA Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 6.975, year: 2015

  7. Recombinant heat shock protein 70 in combination with radiotherapy as a source of tumor antigens to improve dendritic cell immunotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yu-Shan [Department of Radiation Therapy and Oncology, Shin Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan (China); Department of Animal Science, National Ilan University, Ilan, Taiwan (China); Liu, Shih-Jen [Vaccine Research and Development Center, National Health Research Institutes, Miaoli, Taiwan (China); Huang, Su-Chen; Chang, Chao-Chun; Huang, Yi-Chun; Fong, Weng-Lam; Chi, Mau-Shin [Department of Radiation Therapy and Oncology, Shin Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan (China); Chi, Kwan-Hwa, E-mail: m006565@ms.skh.org.tw [Department of Radiation Therapy and Oncology, Shin Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan (China); School of Medicine and Institute of Radiation Science and Image Research, National Yang-Ming Medical University, Taipei, Taiwan (China)

    2012-10-29

    Local radiotherapy (RT) plus intratumoral dendritic cell (DC) injection can mediate immunological response. We hypothesized that co-injection of exogenous recombinant heat shock protein 70 (rHsp70) in combination with RT-DC could be as effective as co-injection of HSP-peptide for evoking specific immune response. rHsp70-prostate-specific antigen (rHSP70C′-PSA) and α-fetoprotein (rHSP70C′-AFP) were used to compare specific response. Growth inhibition of the tumor and the systemic anti-tumor immune response were measured on CT26/PSA and CT26/AFP mice model. Intratumoral co-injection of rHsp70 and DC into the irradiated tumor site induced a more potent anti-tumor immune response than injection of DC alone. rHsp70 was as effective as rHsp70C′-PSA or rHsp70C′-AFP in inducing a tumor-specific cytotoxic T lymphocyte response or tumor growth delay. These results demonstrate that co-administration with rHsp70 and RT could be a simple and effective source of tumor antigens to achieve RT-DC immunotherapy protocol and easy to apply in clinical use.

  8. Recombinant heat shock protein 70 in combination with radiotherapy as a source of tumor antigens to improve dendritic cell immunotherapy

    International Nuclear Information System (INIS)

    Wang, Yu-Shan; Liu, Shih-Jen; Huang, Su-Chen; Chang, Chao-Chun; Huang, Yi-Chun; Fong, Weng-Lam; Chi, Mau-Shin; Chi, Kwan-Hwa

    2012-01-01

    Local radiotherapy (RT) plus intratumoral dendritic cell (DC) injection can mediate immunological response. We hypothesized that co-injection of exogenous recombinant heat shock protein 70 (rHsp70) in combination with RT-DC could be as effective as co-injection of HSP-peptide for evoking specific immune response. rHsp70-prostate-specific antigen (rHSP70C′-PSA) and α-fetoprotein (rHSP70C′-AFP) were used to compare specific response. Growth inhibition of the tumor and the systemic anti-tumor immune response were measured on CT26/PSA and CT26/AFP mice model. Intratumoral co-injection of rHsp70 and DC into the irradiated tumor site induced a more potent anti-tumor immune response than injection of DC alone. rHsp70 was as effective as rHsp70C′-PSA or rHsp70C′-AFP in inducing a tumor-specific cytotoxic T lymphocyte response or tumor growth delay. These results demonstrate that co-administration with rHsp70 and RT could be a simple and effective source of tumor antigens to achieve RT-DC immunotherapy protocol and easy to apply in clinical use.

  9. Kaempferol Inhibits Endoplasmic Reticulum Stress-Associated Mucus Hypersecretion in Airway Epithelial Cells And Ovalbumin-Sensitized Mice.

    Science.gov (United States)

    Park, Sin-Hye; Gong, Ju-Hyun; Choi, Yean-Jung; Kang, Min-Kyung; Kim, Yun-Ho; Kang, Young-Hee

    2015-01-01

    Mucus hypersecretion is an important pathological feature of chronic airway diseases, such as asthma and pulmonary diseases. MUC5AC is a major component of the mucus matrix forming family of mucins in the airways. The initiation of endoplasmic reticulum (ER)-mediated stress responses contributes to the pathogenesis of airway diseases. The present study investigated that ER stress was responsible for airway mucus production and this effect was blocked by the flavonoid kaempferol. Oral administration of ≥10 mg/kg kaempferol suppressed mucus secretion and goblet cell hyperplasia observed in the bronchial airway and lung of BALB/c mice sensitized with ovalbumin (OVA). TGF-β and tunicamycin promoted MUC5AC induction after 72 h in human bronchial airway epithelial BEAS-2B cells, which was dampened by 20 μM kaempferol. Kaempferol inhibited tunicamycin-induced ER stress of airway epithelial cells through disturbing the activation of the ER transmembrane sensor ATF6 and IRE1α. Additionally, this compound demoted the induction of ER chaperones such as GRP78 and HSP70 and the splicing of XBP-1 mRNA by tunicamycin. The in vivo study further revealed that kaempferol attenuated the induction of XBP-1 and IRE1α in epithelial tissues of OVA-challenged mice. TGF-β and tunicamycin induced TRAF2 with JNK activation and such induction was deterred by kaempferol. The inhibition of JNK activation encumbered the XBP-1 mRNA splicing and MUC5AC induction by tunicamycin and TGF-β. These results demonstrate that kaempferol alleviated asthmatic mucus hypersecretion through blocking bronchial epithelial ER stress via the inhibition of IRE1α-TRAF2-JNK activation. Therefore, kaempferol may be a potential therapeutic agent targeting mucus hypersecretion-associated pulmonary diseases.

  10. FLZ Attenuates α-Synuclein-Induced Neurotoxicity by Activating Heat Shock Protein 70.

    Science.gov (United States)

    Bao, Xiu-Qi; Wang, Xiao-Liang; Zhang, Dan

    2017-01-01

    Parkinson's disease (PD) is the second most prevalent neurodegenerative disease. The pathology of PD is caused by progressive degeneration of dopaminergic neurons and is characterized by the presence of intracellular inclusions known as Lewy bodies, composed mainly of α-synuclein. Heat shock proteins (HSPs) are crucial in protein quality control in cells. HSP70 in particular prevents the aggregation of protein aggregation, such as α-synuclein, providing a degree of protection against PD. The compound FLZ has been shown to protect several PD models in previous studies and was reported as an HSP inducer to protect against MPP + -induced neurotoxicity, but the mechanism remains unclear. In this study, we investigated the effects of FLZ-mediated HSP70 induction in α-synuclein transgenic mice and cells. FLZ treatment alleviated motor dysfunction and improved dopaminergic neuronal function in α-synuclein transgenic mice. HSP70 protein expression and transcriptional activity were increased by FLZ treatment, eliciting a reduction of α-synuclein aggregation and associated toxicity. The inhibition of HSP70 by quercetin or HSP70 siRNA markedly attenuated the neuroprotective effects of FLZ, confirming that FLZ exerted a neuroprotective effect through HSP70. We revealed that FLZ directly bound to and increased the expression of Hip, a cochaperone of HSP70, which in turn enhanced HSP70 activity. In conclusion, we defined a critical role for HSP70 and its cochaperones activated by FLZ in preventing neurodegeneration and proposed that targeting the HSP70 system may represent a potential therapy for α-synuclein-related diseases, such as PD.

  11. Growth Inhibition of Re-Challenge B16 Melanoma Transplant by Conjugates of Melanogenesis Substrate and Magnetite Nanoparticles as the Basis for Developing Melanoma-Targeted Chemo-Thermo-Immunotherapy

    Directory of Open Access Journals (Sweden)

    Tomoaki Takada

    2009-01-01

    Full Text Available Melanogenesis substrate, N-propionyl-cysteaminylphenol (NPrCAP, is selectively incorporated into melanoma cells and inhibits their growth by producing cytotoxic free radicals. Magnetite nanoparticles also disintegrate cancer cells and generate heat shock protein (HSP upon exposure to an alternating magnetic field (AMF. This study tested if a chemo-thermo-immunotherapy (CTI therapy strategy can be developed for better management of melanoma by conjugating NPrCAP on the surface of magnetite nanoparticles (NPrCAP/M. We examined the feasibility of this approach in B16 mouse melanoma and evaluated the impact of exposure temperature, frequency, and interval on the inhibition of re-challenged melanoma growth. The therapeutic protocol against the primary transplanted tumor with or without AMF exposure once a day every other day for a total of three treatments not only inhibited the growth of the primary transplant but also prevented the growth of the secondary, re-challenge transplant. The heat-generated therapeutic effect was more significant at a temperature of 43∘C than either 41∘C or 46∘C. NPrCAP/M with AMF exposure, instead of control magnetite alone or without AMF exposure, resulted in the most significant growth inhibition of the re-challenge tumor and increased the life span of the mice. HSP70 production was greatest at 43∘C compared to that with 41∘C or 46∘C. CD+T cells were infiltrated at the site of the re-challenge melanoma transplant.

  12. Corrosion inhibition

    Energy Technology Data Exchange (ETDEWEB)

    Fisher, A O

    1965-12-29

    An acid corrosion-inhibiting composition consists essentially of a sugar, and an alkali metal salt selected from the group consisting of iodides and bromides. The weight ratio of the sugar to the alkali metal salt is between 2:1 and about 20,000:1. Also, a corrosion- inhibited phosphoric acid composition comprising at least about 20 wt% of phosphoric acid and between about 0.1 wt% and about 10 wt% of molasses, and between about 0.0005 wt% and about 1 wt% of potassium iodide. The weight ratio of molasses to iodide is greater than about 2:1. (11 claims)

  13. A case of aminoglycosides induced retinal toxicity treated with megadoses of steroids and an intravitreal dexamethasone implant (Ozurdex(®)).

    Science.gov (United States)

    Hernández Pardines, F; Tapia-Quijada, H; Hueso-Abancens, J R

    2016-06-01

    The case is described of a patient who had a sudden loss of vision in her right eye after glaucoma surgery. A diagnosis of retinal toxicity due to tobramycin (an aminoglycoside) was reached, which was characterised by retinal whitening with a red cherry stain, macular oedema, and vasculitis that progressed to papillary and macular atrophy with arteriolar sclerosis. Given the severity of symptoms an early attempt was made with megadoses of steroids and an intravitreal dexamethasone implant (Ozurdex®, Allergan S.A.), without response. Aminoglycoside toxicity is a rare, idiosyncratic, very serious complication for which there is no effective treatment. Copyright © 2016 Sociedad Española de Oftalmología. Published by Elsevier España, S.L.U. All rights reserved.

  14. Hsp40 interacts directly with the native state of the yeast prion protein Ure2 and inhibits formation of amyloid-like fibrils.

    Science.gov (United States)

    Lian, Hui-Yong; Zhang, Hong; Zhang, Zai-Rong; Loovers, Harriët M; Jones, Gary W; Rowling, Pamela J E; Itzhaki, Laura S; Zhou, Jun-Mei; Perrett, Sarah

    2007-04-20

    Ure2 is the protein determinant of the [URE3] prion phenotype in Saccharomyces cerevisiae and consists of a flexible N-terminal prion-determining domain and a globular C-terminal glutathione transferase-like domain. Overexpression of the type I Hsp40 member Ydj1 in yeast cells has been found to result in the loss of [URE3]. However, the mechanism of prion curing by Ydj1 remains unclear. Here we tested the effect of overexpression of Hsp40 members Ydj1, Sis1, and Apj1 and also Hsp70 co-chaperones Cpr7, Cns1, Sti1, and Fes1 in vivo and found that only Ydj1 showed a strong curing effect on [URE3]. We also investigated the interaction of Ydj1 with Ure2 in vitro. We found that Ydj1 was able to suppress formation of amyloid-like fibrils of Ure2 by delaying the process of fibril formation, as monitored by thioflavin T binding and atomic force microscopy imaging. Controls using bovine serum albumin, Sis1, or the human Hsp40 homologues Hdj1 or Hdj2 showed no significant inhibitory effect. Ydj1 was only effective when added during the lag phase of fibril formation, suggesting that it interacts with Ure2 at an early stage in fibril formation and delays the nucleation process. Using surface plasmon resonance and size exclusion chromatography, we demonstrated a direct interaction between Ydj1 and both wild type and N-terminally truncated Ure2. In contrast, Hdj2, which did not suppress fibril formation, did not show this interaction. The results suggest that Ydj1 inhibits Ure2 fibril formation by binding to the native state of Ure2, thus delaying the onset of oligomerization.

  15. The stress protein heat shock cognate 70 (Hsc70) inhibits the Transient Receptor Potential Vanilloid type 1 (TRPV1) channel.

    Science.gov (United States)

    Iftinca, Mircea; Flynn, Robyn; Basso, Lilian; Melo, Helvira; Aboushousha, Reem; Taylor, Lauren; Altier, Christophe

    2016-01-01

    Specialized cellular defense mechanisms prevent damage from chemical, biological, and physical hazards. The heat shock proteins have been recognized as key chaperones that maintain cell survival against a variety of exogenous and endogenous stress signals including noxious temperature. However, the role of heat shock proteins in nociception remains poorly understood. We carried out an expression analysis of the constitutively expressed 70 kDa heat-shock cognate protein, a member of the stress-induced HSP70 family in lumbar dorsal root ganglia from a mouse model of Complete Freund's Adjuvant-induced chronic inflammatory pain. We used immunolabeling of dorsal root ganglion neurons, behavioral analysis and patch clamp electrophysiology in both dorsal root ganglion neurons and HEK cells transfected with Hsc70 and Transient Receptor Potential Channels to examine their functional interaction in heat shock stress condition. We report an increase in protein levels of Hsc70 in mouse dorsal root ganglia, 3 days post Complete Freund's Adjuvant injection in the hind paw. Immunostaining of Hsc70 was observed in most of the dorsal root ganglion neurons, including the small size nociceptors immunoreactive to the TRPV1 channel. Standard whole-cell patch-clamp technique was used to record Transient Receptor Potential Vanilloid type 1 current after exposure to heat shock. We found that capsaicin-evoked currents are inhibited by heat shock in dorsal root ganglion neurons and transfected HEK cells expressing Hsc70 and TRPV1. Blocking Hsc70 with matrine or spergualin compounds prevented heat shock-induced inhibition of the channel. We also found that, in contrast to TRPV1, both the cold sensor channels TRPA1 and TRPM8 were unresponsive to heat shock stress. Finally, we show that inhibition of TRPV1 depends on the ATPase activity of Hsc70 and involves the rho-associated protein kinase. Our work identified Hsc70 and its ATPase activity as a central cofactor of TRPV1 channel function

  16. l-Carnitine Modulates Epileptic Seizures in Pentylenetetrazole-Kindled Rats via Suppression of Apoptosis and Autophagy and Upregulation of Hsp70

    Directory of Open Access Journals (Sweden)

    Abdelaziz M. Hussein

    2018-03-01

    Full Text Available l-Carnitine is a unique nutritional supplement for athletes that has been recently studied as a potential treatment for certain neuropsychiatric disorders. However, its efficacy in seizure control has not been investigated. Sprague Dawley rats were randomly assigned to receive either saline (Sal (negative control or pentylenetetrazole (PTZ 40 mg/kg i.p. × 3 times/week × 3 weeks. The PTZ group was further subdivided into two groups, the first received oral l-carnitine (l-Car (100 mg/kg/day × 4 weeks (PTZ + l-Car, while the second group received saline (PTZ + Sal. Daily identification and quantification of seizure scores, time to the first seizure and the duration of seizures were performed in each animal. Molecular oxidative markers were examined in the animal brains. l-Car treatment was associated with marked reduction in seizure score (p = 0.0002 that was indicated as early as Day 2 of treatment and continued throughout treatment duration. Furthermore, l-Car significantly prolonged the time to the first seizure (p < 0.0001 and shortened seizure duration (p = 0.028. In addition, l-Car administration for four weeks attenuated PTZ-induced increase in the level of oxidative stress marker malondialdehyde (MDA (p < 0.0001 and reduced the activity of catalase enzyme (p = 0.0006 and increased antioxidant GSH activity (p < 0.0001. Moreover, l-Car significantly reduced PTZ-induced elevation in protein expression of caspase-3 (p < 0.0001 and β-catenin (p < 0.0001. Overall, our results suggest a potential therapeutic role of l-Car in seizure control and call for testing these preclinical results in a proof of concept pilot clinical study.

  17. Effects of 200 Gy 60Co-γ Radiation on the Regulation of Antioxidant Enzymes, Hsp70 Genes, and Serum Molecules of Plutella xylostella (Linnaeus).

    Science.gov (United States)

    Li, Xiaoxue; Luo, Lingyan; Karthi, Sengodan; Zhang, Ke; Luo, Jianjun; Hu, Qiongbo; Weng, Qunfang

    2018-04-26

    The diamondback moth, Plutella xylostella (Linnaeus), is one of the notorious pests causing substantial loses to many cruciferous vegetables across the nations. The effects of 60 Co-γ radiation on physiology of P. xylostella were investigated and the results displayed that 200 Gy irradiation significantly alters the antioxidant enzyme regulation in six-day-old male pupae of P. xylostella . First, in our research, we detected Oxidase system and stress response mechanism of irradiated pupae, the results displayed that 200 Gy irradiation significantly alters the antioxidant enzyme regulation in six-day-old male pupae of P. xylostella . The levels of superoxide dismutase (SOD) and catalase (CAT) were increased significantly in contrast the level of peroxidase (POD) and glutathione S-transferase (GST) were decreased in 12⁻24 h post-treatment. The heat shock proteins (Hsps) gene expression level was significant increasing, maximum > 2-folds upregulation of genes were observed in peak. However, they also had a trend of gradual recovery with development. Second, we detected the testis lactate dehydrogenase (LDH) and acid phosphatase (ACP) activity found that in male adults testis they increased significantly than control during its development. Thus the present research investigation highlights that the 60 Co-γ radiation treatments alters the physiological development of diamondback moth. The results showed that 200 Gy dosage resulted in stress damage to the body and reproductive system of the diamondback moth.

  18. Effects of 200 Gy 60Co-γ Radiation on the Regulation of Antioxidant Enzymes, Hsp70 Genes, and Serum Molecules of Plutella xylostella (Linnaeus

    Directory of Open Access Journals (Sweden)

    Xiaoxue Li

    2018-04-01

    Full Text Available The diamondback moth, Plutella xylostella (Linnaeus, is one of the notorious pests causing substantial loses to many cruciferous vegetables across the nations. The effects of 60Co-γ radiation on physiology of P. xylostella were investigated and the results displayed that 200 Gy irradiation significantly alters the antioxidant enzyme regulation in six-day-old male pupae of P. xylostella. First, in our research, we detected Oxidase system and stress response mechanism of irradiated pupae, the results displayed that 200 Gy irradiation significantly alters the antioxidant enzyme regulation in six-day-old male pupae of P. xylostella. The levels of superoxide dismutase (SOD and catalase (CAT were increased significantly in contrast the level of peroxidase (POD and glutathione S-transferase (GST were decreased in 12–24 h post-treatment. The heat shock proteins (Hsps gene expression level was significant increasing, maximum > 2-folds upregulation of genes were observed in peak. However, they also had a trend of gradual recovery with development. Second, we detected the testis lactate dehydrogenase (LDH and acid phosphatase (ACP activity found that in male adults testis they increased significantly than control during its development. Thus the present research investigation highlights that the 60Co-γ radiation treatments alters the physiological development of diamondback moth. The results showed that 200 Gy dosage resulted in stress damage to the body and reproductive system of the diamondback moth.

  19. Chaperoning Proteins for Destruction: Diverse Roles of Hsp70 Chaperones and their Co-Chaperones in Targeting Misfolded Proteins to the Proteasome

    Directory of Open Access Journals (Sweden)

    Ayala Shiber

    2014-07-01

    Full Text Available Molecular chaperones were originally discovered as heat shock-induced proteins that facilitate proper folding of proteins with non-native conformations. While the function of chaperones in protein folding has been well documented over the last four decades, more recent studies have shown that chaperones are also necessary for the clearance of terminally misfolded proteins by the Ub-proteasome system. In this capacity, chaperones protect misfolded degradation substrates from spontaneous aggregation, facilitate their recognition by the Ub ligation machinery and finally shuttle the ubiquitylated substrates to the proteasome. The physiological importance of these functions is manifested by inefficient proteasomal degradation and the accumulation of protein aggregates during ageing or in certain neurodegenerative diseases, when chaperone levels decline. In this review, we focus on the diverse roles of stress-induced chaperones in targeting misfolded proteins to the proteasome and the consequences of their compromised activity. We further discuss the implications of these findings to the identification of new therapeutic targets for the treatment of amyloid diseases.

  20. Reproducible fashion of the HSP70B' promoter-induced cytotoxic response on a live cell-based biosensor by cell cycle synchronization.

    Science.gov (United States)

    Migita, Satoshi; Wada, Ken-Ichi; Taniguchi, Akiyoshi

    2010-10-15

    Live cell-based sensors potentially provide functional information about the cytotoxic effect of reagents on various signaling cascades. Cells transfected with a reporter vector derived from a cytotoxic response promoter can be used as intelligent cytotoxicity sensors (i.e., sensor cells). We have combined sensor cells and a microfluidic cell culture system that can achieve several laminar flows, resulting in a reliable high-throughput cytotoxicity detection system. These sensor cells can also be applied to single cell arrays. However, it is difficult to detect a cellular response in a single cell array, due to the heterogeneous response of sensor cells. The objective of this study was cell homogenization with cell cycle synchronization to enhance the response of cell-based biosensors. Our previously established stable sensor cells were brought into cell cycle synchronization under serum-starved conditions and we then investigated the cadmium chloride-induced cytotoxic response at the single cell level. The GFP positive rate of synchronized cells was approximately twice as high as that of the control cells, suggesting that cell homogenization is an important step when using cell-based biosensors with microdevices, such as a single cell array. Copyright 2010 Wiley Periodicals, Inc.

  1. The role of inducible Hsp70, and other heat shock proteins, in adaptive complex of cold tolerance of the fruit fly (Drosophila melanogaster)

    Czech Academy of Sciences Publication Activity Database

    Štětina, Tomáš; Košťál, Vladimír; Korbelová, Jaroslava

    2015-01-01

    Roč. 10, č. 6 (2015), e0128976 E-ISSN 1932-6203 R&D Projects: GA ČR GA13-01057S; GA MŠk LH12103 Grant - others:GA JU(CZ) 038/2014/P Institutional support: RVO:60077344 Keywords : up-regulation * flesh flay * gene-expression Subject RIV: ED - Physiology Impact factor: 3.057, year: 2015 http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0128976

  2. l-Carnitine Modulates Epileptic Seizures in Pentylenetetrazole-Kindled Rats via Suppression of Apoptosis and Autophagy and Upregulation of Hsp70.

    Science.gov (United States)

    Hussein, Abdelaziz M; Adel, Mohamed; El-Mesery, Mohamed; Abbas, Khaled M; Ali, Amr N; Abulseoud, Osama A

    2018-03-14

    l-Carnitine is a unique nutritional supplement for athletes that has been recently studied as a potential treatment for certain neuropsychiatric disorders. However, its efficacy in seizure control has not been investigated. Sprague Dawley rats were randomly assigned to receive either saline (Sal) (negative control) or pentylenetetrazole (PTZ) 40 mg/kg i.p. × 3 times/week × 3 weeks. The PTZ group was further subdivided into two groups, the first received oral l-carnitine (l-Car) (100 mg/kg/day × 4 weeks) (PTZ + l-Car), while the second group received saline (PTZ + Sal). Daily identification and quantification of seizure scores, time to the first seizure and the duration of seizures were performed in each animal. Molecular oxidative markers were examined in the animal brains. l-Car treatment was associated with marked reduction in seizure score ( p = 0.0002) that was indicated as early as Day 2 of treatment and continued throughout treatment duration. Furthermore, l-Car significantly prolonged the time to the first seizure ( p l-Car administration for four weeks attenuated PTZ-induced increase in the level of oxidative stress marker malondialdehyde (MDA) ( p l-Car significantly reduced PTZ-induced elevation in protein expression of caspase-3 ( p l-Car in seizure control and call for testing these preclinical results in a proof of concept pilot clinical study.

  3. Plasmodium falciparum encodes a single cytosolic type I Hsp40 that functionally interacts with Hsp70 and is upregulated by heat shock

    CSIR Research Space (South Africa)

    Botha, M

    2011-07-01

    Full Text Available M, and growth was 385 continued at 30?C for 4 h. Cells were pelleted by 386 centrifugation, quick-frozen, and stored at ?80?C. To 387 isolate the expressed PfHsp40, the cell pellets were thawed 388 and resuspended in 10 ml of lysis buffer (10 mM Tris, 389 p... (Shonhai et al. 2008), ATP has been 522included to demonstrate the nucleotide dependence of the 523MDH aggregation suppression; this control was not repeated 524here. Protein concentrations were calculated assuming the 525monomeric forms of the relevant...

  4. Down-regulation of cellular FLICE-inhibitory protein (Long Form contributes to apoptosis induced by Hsp90 inhibition in human lung cancer cells

    Directory of Open Access Journals (Sweden)

    Wang Qilin

    2012-12-01

    Full Text Available Abstract Background Cellular FLICE-Inhibitory Protein (long form, c-FLIPL is a critical negative regulator of death receptor-mediated apoptosis. Overexpression of c-FLIPL has been reported in many cancer cell lines and is associated with chemoresistance. In contrast, down-regulation of c-FLIP may drive cancer cells into cellular apoptosis. This study aims to demonstrate that inhibition of the heat shock protein 90 (Hsp90 either by inhibitors geldanamycin/17-N-Allylamino-17-demethoxygeldanamycin (GA/17-AAG or siRNA technique in human lung cancer cells induces c-FLIPL degradation and cellular apoptosis through C-terminus of Hsp70-interacting protein (CHIP-mediated mechanisms. Methods Calu-1 and H157 cell lines (including H157-c-FLIPL overexpressing c-FLIPL and control cell H157-lacZ were treated with 17-AAG and the cell lysates were prepared to detect the given proteins by Western Blot and the cell survival was assayed by SRB assay. CHIP and Hsp90 α/β proteins were knocked down by siRNA technique. CHIP and c-FLIPL plasmids were transfected into cells and immunoprecipitation experiments were performed to testify the interactions between c-FLIPL, CHIP and Hsp90. Results c-FLIPL down-regulation induced by 17-AAG can be reversed with the proteasome inhibitor MG132, which suggested that c-FLIPL degradation is mediated by a ubiquitin-proteasome system. Inhibition of Hsp90α/β reduced c-FLIPL level, whereas knocking down CHIP expression with siRNA technique inhibited c-FLIPL degradation. Furthermore, c-FLIPL and CHIP were co-precipitated in the IP complexes. In addition, overexpression of c-FLIPL can rescue cancer cells from apoptosis. When 17-AAG was combined with an anti-cancer agent celecoxib(CCB, c-FLIPL level declined further and there was a higher degree of caspase activation. Conclusion We have elucidated c-FLIPL degradation contributes to apoptosis induced by Hsp90 inhibition, suggesting c-FLIP and Hsp90 may be the promising combined targets

  5. Baicalein inhibition of oxidative-stress-induced apoptosis via modulation of ERKs activation and induction of HO-1 gene expression in rat glioma cells C6

    International Nuclear Information System (INIS)

    Chen, Y.-C.; Chow, J.-M.; Lin, C.-W.; Wu, C.-Y.; Shen, S.-C.

    2006-01-01

    In the present study, we examined the protective mechanism of baicalein (BE) and its glycoside, baicalin (BI), on hydrogen-peroxide (H 2 O 2 )-induced cell death in rat glioma C6 cells. Results of the MTT assay, LDH release assay, and morphological observation showed that H 2 O 2 addition reduced the viability of C6 cells, and this was prevented by the addition of BE but not BI. Incubation of C6 cells with BE significantly decreased the intracellular peroxide level induced by H 2 O 2 according to flow cytometric analysis using DCHF-DA as a fluorescent substrate. Suppression of H 2 O 2 -induced apoptotic events including DNA ladders, hypodiploid cells, and activation of caspases 3, 8, and, 9 by BE but not BI was identified in C6 cells. The cytotoxicity and phosphorylation of ERK proteins induced by H 2 O 2 were blocked by the ERK inhibitor PD98059. Catalase addition prevented H 2 O 2 -induced ROS production, ERKs protein phosphorylation, and cell death, and BE dose-dependently inhibited H 2 O 2 -induced ERK protein phosphorylation in C6 cells. These data suggest that ROS-scavenging activity is involved in BE prevention of H 2 O 2 -induced cell death via blocking ERKs activation. Additionally, BE but not BI induced heat shock protein 32 (HSP32; HO-1) protein expression in both time- and dose-dependent manners, but not heme oxygenase 2 (HO-2), heat shock protein 70 (HSP70), or heat shock protein 90 (HSP90) protein expression. In the absence of H 2 O 2 , BE induces ERKs protein phosphorylation, and HO-1 protein expression induced by BE was blocked by the addition of cycloheximide, actinomycin D, and the ERK inhibitor PD98059. The addition of the HO inhibitor ZnPP inhibited the protective effect of BE against H 2 O 2 -induced cytotoxicity in C6 cells according to the MTT assay and apoptotic morphology under microscopic observation, accompanied by blocking the ROS-scavenging activity of BE in C6 cells. However, BE treatment was unable to protect C6 cells from C2-ceramide

  6. Bcl-2 associated athanogene 5 (Bag5) is overexpressed in prostate cancer and inhibits ER-stress induced apoptosis

    International Nuclear Information System (INIS)

    Bruchmann, Anja; Roller, Corinna; Walther, Tamara Vanessa; Schäfer, Georg; Lehmusvaara, Sara; Visakorpi, Tapio; Klocker, Helmut; Cato, Andrew C B; Maddalo, Danilo

    2013-01-01

    The Bag (Bcl-2 associated athanogene) family of proteins consists of 6 members sharing a common, single-copied Bag domain through which they interact with the molecular chaperone Hsp70. Bag5 represents an exception in the Bag family since it consists of 5 Bag domains covering the whole protein. Bag proteins like Bag1 and Bag3 have been implicated in tumor growth and survival but it is not known whether Bag5 also exhibits this function. Bag5 mRNA and protein expression levels were investigated in prostate cancer patient samples using real-time PCR and immunoblot analyses. In addition immunohistological studies were carried out to determine the expression of Bag5 in tissue arrays. Analysis of Bag5 gene expression was carried out using one-way ANOVA and Bonferroni’s Multiple Comparison test. The mean values of the Bag5 stained cells in the tissue array was analyzed by Mann-Whitney test. Functional studies of the role of Bag5 in prostate cancer cell lines was performed using overexpression and RNA interference analyses. Our results show that Bag5 is overexpressed in malignant prostate tissue compared to benign samples. In addition we could show that Bag5 levels are increased following endoplasmic reticulum (ER)-stress induction, and Bag5 relocates from the cytoplasm to the ER during this process. We also demonstrate that Bag5 interacts with the ER-resident chaperone GRP78/BiP and enhances its ATPase activity. Bag5 overexpression in 22Rv.1 prostate cancer cells inhibited ER-stress induced apoptosis in the unfolded protein response by suppressing PERK-eIF2-ATF4 activity while enhancing the IRE1-Xbp1 axis of this pathway. Cells expressing high levels of Bag5 showed reduced sensitivity to apoptosis induced by different agents while Bag5 downregulation resulted in increased stress-induced cell death. We have therefore shown that Bag5 is overexpressed in prostate cancer and plays a role in ER-stress induced apoptosis. Furthermore we have identified GRP78/BiP as a novel

  7. INHIBITION IN SPEAKING PERFORMANCE

    OpenAIRE

    Humaera, Isna

    2015-01-01

    The most common problem encountered by the learner in the languageacquisition process is learner inhibition. Inhibition refers to a temperamentaltendency to display wariness, fearfulness, or restrain in response tounfamiliar people, objects, and situations. There are some factors that causeinhibition, such as lack of motivation, shyness, self-confidence, self-esteem,and language ego. There are also levels of inhibition, it refers to kinds ofinhibition and caused of inhibition itself. Teacher ...

  8. Pifithrin-μ, an inhibitor of heat-shock protein 70, can increase the antitumor effects of hyperthermia against human prostate cancer cells.

    Directory of Open Access Journals (Sweden)

    Kazumasa Sekihara

    Full Text Available Hyperthermia (HT improves the efficacy of anti-cancer radiotherapy and chemotherapy. However, HT also inevitably evokes stress responses and increases the expression of heat-shock proteins (HSPs in cancer cells. Among the HSPs, HSP70 is known as a pro-survival protein. In this study, we investigated the sensitizing effect of pifithrin (PFT-μ, a small molecule inhibitor of HSP70, when three human prostate cancer cell lines (LNCaP, PC-3, and DU-145 were treated with HT (43°C for 2 h. All cell lines constitutively expressed HSP70, and HT further increased its expression in LNCaP and DU-145. Knockdown of HSP70 with RNA interference decreased the viability and colony-forming ability of cancer cells. PFT-μ decreased the viabilities of all cell lines at one-tenth the dose of Quercetin, a well-known HSP inhibitor. The combination therapy with suboptimal doses of PFT-μ and HT decreased the viability of cancer cells most effectively when PFT-μ was added immediately before HT, and this combination effect was abolished by pre-knockdown of HSP70, suggesting that the effect was mediated via HSP70 inhibition. The combination therapy induced cell death, partially caspase-dependent, and decreased proliferating cancer cells, with decreased expression of c-Myc and cyclin D1 and increased expression of p21(WAF1/Cip, indicating arrest of cell growth. Additionally, the combination therapy significantly decreased the colony-forming ability of cancer cells compared to therapy with either alone. Furthermore, in a xenograft mouse model, the combination therapy significantly inhibited PC-3 tumor growth. These findings suggest that PFT-μ can effectively enhance HT-induced antitumor effects via HSP70 inhibition by inducing cell death and arrest of cell growth, and that PFT-μ is a promising agent for use in combination with HT to treat prostate cancer.

  9. Elongation Factor Tu and Heat Shock Protein 70 Are Membrane-Associated Proteins from Mycoplasma ovipneumoniae Capable of Inducing Strong Immune Response in Mice.

    Directory of Open Access Journals (Sweden)

    Fei Jiang

    Full Text Available Chronic non-progressive pneumonia, a disease that has become a worldwide epidemic has caused considerable loss to sheep industry. Mycoplasma ovipneumoniae (M. ovipneumoniae is the causative agent of interstitial pneumonia in sheep, goat and bighorn. We here have identified by immunogold and immunoblotting that elongation factor Tu (EF-Tu and heat shock protein 70 (HSP 70 are membrane-associated proteins on M. ovipneumonaiea. We have evaluated the humoral and cellular immune responses in vivo by immunizing BALB/c mice with both purified recombinant proteins rEF-Tu and rHSP70. The sera of both rEF-Tu and rHSP70 treated BALB/c mice demonstrated increased levels of IgG, IFN-γ, TNF-α, IL-12(p70, IL-4, IL-5 and IL-6. In addition, ELISPOT assay showed significant increase in IFN-γ+ secreting lymphocytes in the rHSP70 group when compared to other groups. Collectively our study reveals that rHSP70 induces a significantly better cellular immune response in mice, and may act as a Th1 cytokine-like adjuvant in immune response induction. Finally, growth inhibition test (GIT of M. ovipneumoniae strain Y98 showed that sera from rHSP70 or rEF-Tu-immunized mice inhibited in vitro growth of M. ovipneumoniae. Our data strongly suggest that EF-Tu and HSP70 of M. ovipneumoniae are membrane-associated proteins capable of inducing antibody production, and cytokine secretion. Therefore, these two proteins may be potential candidates for vaccine development against M. ovipneumoniae infection in sheep.

  10. Proteomic analysis reveals heat shock protein 70 has a key role in polycythemia Vera.

    Science.gov (United States)

    Gallardo, Miguel; Barrio, Santiago; Fernandez, Marisol; Paradela, Alberto; Arenas, Alicia; Toldos, Oscar; Ayala, Rosa; Albizua, Enriqueta; Jimenez, Ana; Redondo, Santiago; Garcia-Martin, Rosa Maria; Gilsanz, Florinda; Albar, Juan Pablo; Martinez-Lopez, Joaquin

    2013-11-19

    JAK-STAT signaling through the JAK2V617F mutation is central to the pathogenesis of myeloproliferative neoplasms (MPN). However, other events could precede the JAK2 mutation. The aim of this study is to analyze the phenotypic divergence between polycytemia vera (PV) and essential thrombocytemia (ET) to find novel therapeutics targets by a proteomic and functional approach to identify alternative routes to JAK2 activation. Through 2D-DIGE and mass spectrometry of granulocyte protein from 20 MPN samples, showed differential expression of HSP70 in PV and ET besides other 60 proteins. Immunohistochemistry of 46 MPN bone marrow samples confirmed HSP70 expression. The median of positive granulocytes was 80% in PV (SD 35%) vs. 23% in ET (SD 34.25%). In an ex vivo model KNK437 was used as an inhibition model assay of HSP70, showed dose-dependent inhibition of cell growth and burst formation unit erythroid (BFU-E) in PV and ET, increased apoptosis in the erythroid lineage, and decreased pJAK2 signaling, as well as a specific siRNA for HSP70. These data suggest a key role for HSP70 in proliferation and survival of the erythroid lineage in PV, and may represent a potential therapeutic target in MPN, especially in PV.

  11. Inhibition of lactation.

    Science.gov (United States)

    Llewellyn-Jones, D

    1975-01-01

    The mechanism and hormonal regulation of lactation is explained and illustrated with a schematic representation. Circulating estrogen above a critical amount seems to be the inhibitory factor controlling lactation during pregnancy. Once delivery occurs, the level of estrogen falls, that of prolactin rises, and lactation begins. Nonsuckling can be used to inhibit lactation. Estrogens can also be used to inhibit lactation more quickly and with less pain. The reported association between estrogens and puerperal thromboembolism cannot be considered conclusive due to defects in the reporting studies. There is no reason not to use estrogens in lactation inhibition except for women over 35 who experienced a surgical delivery. Alternative therapy is available for these women. The recently-developed drug, brom-ergocryptine, may replace other methods of lactation inhibition.

  12. Identification of genes involved in low aminoglycoside-induced SOS response in Vibrio cholerae: a role for transcription stalling and Mfd helicase.

    Science.gov (United States)

    Baharoglu, Zeynep; Babosan, Anamaria; Mazel, Didier

    2014-02-01

    Sub-inhibitory concentrations (sub-MIC) of antibiotics play a very important role in selection and development of resistances. Unlike Escherichia coli, Vibrio cholerae induces its SOS response in presence of sub-MIC aminoglycosides. A role for oxidized guanine residues was observed, but the mechanisms of this induction remained unclear. To select for V. cholerae mutants that do not induce low aminoglycoside-mediated SOS induction, we developed a genetic screen that renders induction of SOS lethal. We identified genes involved in this pathway using two strategies, inactivation by transposition and gene overexpression. Interestingly, we obtained mutants inactivated for the expression of proteins known to destabilize the RNA polymerase complex. Reconstruction of the corresponding mutants confirmed their specific involvement in induction of SOS by low aminoglycoside concentrations. We propose that DNA lesions formed on aminoglycoside treatment are repaired through the formation of single-stranded DNA intermediates, inducing SOS. Inactivation of functions that dislodge RNA polymerase leads to prolonged stalling on these lesions, which hampers SOS induction and repair and reduces viability under antibiotic stress. The importance of these mechanisms is illustrated by a reduction of aminoglycoside sub-MIC. Our results point to a central role for transcription blocking at DNA lesions in SOS induction, so far underestimated.

  13. Membrane-bound heat shock proteins facilitate the uptake of dying cells and cross-presentation of cellular antigen.

    Science.gov (United States)

    Zhu, Haiyan; Fang, Xiaoyun; Zhang, Dongmei; Wu, Weicheng; Shao, Miaomiao; Wang, Lan; Gu, Jianxin

    2016-01-01

    Heat shock proteins (HSPs) were originally identified as stress-responsive proteins and serve as molecular chaperones in different intracellular compartments. Translocation of HSPs to the cell surface and release of HSPs into the extracellular space have been observed during the apoptotic process and in response to a variety of cellular stress. Here, we report that UV irradiation and cisplatin treatment rapidly induce the expression of membrane-bound Hsp60, Hsp70, and Hsp90 upstream the phosphatidylserine exposure. Membrane-bound Hsp60, Hsp70 and Hsp90 could promote the release of IL-6 and IL-1β as well as DC maturation by the evaluation of CD80 and CD86 expression. On the other hand, Hsp60, Hsp70 and Hsp90 on cells could facilitate the uptake of dying cells by bone marrow-derived dendritic cells. Lectin-like oxidized LDL receptor-1 (LOX-1), as a common receptor for Hsp60, Hsp70, and Hsp90, is response for their recognition and mediates the uptake of dying cells. Furthermore, membrane-bound Hsp60, Hsp70 and Hsp90 could promote the cross-presentation of OVA antigen from E.G7 cells and inhibition of the uptake of dying cells by LOX-1 decreases the cross-presentation of cellular antigen. Therefore, the rapid exposure of HSPs on dying cells at the early stage allows for the recognition by and confers an activation signal to the immune system.

  14. Bag3 promotes resistance to apoptosis through Bcl-2 family members in non-small cell lung cancer.

    Science.gov (United States)

    Zhang, Yong; Wang, Jian-Hua; Lu, Qiang; Wang, Yun-Jie

    2012-01-01

    In non-small cell lung cancer (NSCLC) certain molecular characteristics, which are related to molecular alterations have been investigated. These are responsible for both the initiation and maintenance of the malignancy in lung cancer. The aim of this study was to evaluate the influence of Bag3 (Bcl-2 associated athanogene 3) in the regulation of apoptosis on NSCLC. Bag3 and Hsp70 expression were examined by immunohistochemistry to confirm their potential roles in the prevalence of NSCLC. We also established human normal bronchial epithelial cells and HOP-62 cell line as the model to analyze cell apoptosis and the expression of Hsp70, Bcl-XL and Bcl-2, which were affected by Bag3. In this study, we found that Bag3 and Hsp70 are highly expressed in few tissues and cell lines of NSCLC. Bag3 inhibits apoptosis in human normal bronchial epithelial cell lines and sustain the survival of NSCLC cells. Bag3, Hsp70, Bcl-XL and Bcl-2 are up-regulated in NSCLC cell lines. At the same time, the silencing of Bag3 results in diminishing protein levels of Bcl-XL and Bcl-2. The results of immunoprecipitation identified that Bag3 could interact with Hsp70, Bcl-XL and Bcl-2 NSCLC cells directly or indirectly. We conclude that NSCLC cells were protected from apoptosis through increasing Bag3 expression and consequently promoted the expression of Bcl-XL and Bcl-2.

  15. Inhibition of p38 MAPK during cellular activation modulate gene expression of head kidney leukocytes isolated from Atlantic salmon (Salmo salar) fed soy bean oil or fish oil based diets.

    Science.gov (United States)

    Holen, E; Winterthun, S; Du, Z-Y; Krøvel, A V

    2011-01-01

    Head kidney leukocytes isolated from Atlantic salmon fed either a diet based on fish oil (FO) or soy bean oil (VO) were used in order to evaluate if different lipid sources could contribute to cellular activation of the salmon innate immune system. A specific inhibitor of p38 MAPK, SB202190, was used to investigate the effect of lipopolysaccharide (LPS) signalling in the head kidney leukocytes. The results show that LPS up regulate IL-1β, TNF-α, Cox2 expression in leukocytes isolated from fish fed either diet. The p38 MAPK inhibitor, SB202190, reduced the LPS induced expression of these genes in both dietary groups. In LPS stimulated leukocytes isolated from VO fed fish, SB202190 showed a clear dose dependent inhibitory effect on IL-1β, TNF-α and Cox2 expression. This effect was also observed for Cox2 in leukocytes isolated from FO fed fish. Furthermore, there was a stronger mean induction of Cox2 in LPS stimulated leucocytes isolated from the VO-group compared to LPS stimulated leukocytes isolated from the FO-group. In both dietary groups, LPS stimulation of salmon head kidney leukocytes increased the induction of CD83, a dendrite cell marker, while the inhibitor reduced CD83 expression in the VO fed fish only. The inhibitor also clearly reduced hsp27 expression in VO fed fish. Indicating a p38 MAPK feedback loop, LPS significantly inhibited the expression of p38MAPK itself in both diets, while SB202190 increased p38MAPK expression especially in the VO diet group. hsp70 expression was not affected by any treatment or feed composition. There were also differences in p38MAPK protein phosphorylation comparing treatment groups but no obvious difference comparing the two dietary groups. The results indicate that dietary fatty acids have the ability to modify signalling through p38 MAPK which may have consequences for the fish's ability to handle infections and stress. Signalling through p38MAPK is ligand dependent and affects gene and protein expression differently

  16. Enzyme inhibition by iminosugars

    DEFF Research Database (Denmark)

    López, Óscar; Qing, Feng-Ling; Pedersen, Christian Marcus

    2013-01-01

    Imino- and azasugar glycosidase inhibitors display pH dependant inhibition reflecting that both the inhibitor and the enzyme active site have groups that change protonation state with pH. With the enzyme having two acidic groups and the inhibitor one basic group, enzyme-inhibitor complexes...

  17. Quorum sensing inhibition

    DEFF Research Database (Denmark)

    Persson, T.; Givskov, Michael Christian; Nielsen, J.

    2005-01-01

    /receptor transcriptional regulator in some clinically relevant Gram-negative bacteria. The present review contains all reported compound types that are currently known to inhibit the QS transcriptional regulator in Gram-negative bacteria. These compounds are sub-divided into two main groups, one comprising structural...

  18. Cooperation for Better Inhibiting.

    Science.gov (United States)

    Novoa, Eva Maria; Ribas de Pouplana, Lluís

    2015-06-18

    Cladosporin is an antimalarial drug that acts as an ATP-mimetic to selectively inhibit Plasmodium lysyl-tRNA synthetase. Using multiple crystal structures, Fang et al. (2015) reveal in this issue of Chemistry & Biology the fascinating mechanism responsible for cladosporin selectivity. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Inhibition of glutathione biosynthesis alters compartmental redox status and the thiol proteome in organogenesis-stage rat conceptuses.

    Science.gov (United States)

    Harris, Craig; Shuster, Daniel Z; Roman Gomez, Rosaicela; Sant, Karilyn E; Reed, Matthew S; Pohl, Jan; Hansen, Jason M

    2013-10-01

    oxidation was seen in the BSO-treated AF compartment after 6 h. Biotinylated iodoacetamide (BIAM) labeling of proteins revealed the significant thiol oxidation of many EMB proteins following BSO treatment. Quantitative changes in the thiol proteome, associated with developmentally relevant pathways, were detected using isotope coded affinity tag (ICAT) labeling and mass spectroscopy. Adaptive pathways were selectively enriched with increased concentrations of proteins involved in mRNA processing (splicesome) and mRNA stabilization (glycolysis, GAPDH), as well as protein synthesis (aminoacyl-tRNA) and protein folding (antigen processing, Hsp70, protein disulfide isomerase). These results show the ability of chemical and environmental modulators to selectively alter compartmental intracellular and extracellular GSH and Cys concentrations and change their corresponding E(h) within the intact viable conceptus. The altered E(h) were also of sufficient magnitude to alter the redox proteome and change relative protein concentrations, suggesting that the mechanistic links through which environmental factors inform and regulate developmental signaling pathways may be discovered using systems developmental biology techniques. Copyright © 2013 Elsevier Inc. All rights reserved.

  20. Plastics for corrosion inhibition

    CERN Document Server

    Goldade, Victor A; Makarevich, Anna V; Kestelman, Vladimir N

    2005-01-01

    The development of polymer composites containing inhibitors of metal corrosion is an important endeavour in modern materials science and technology. Corrosion inhibitors can be located in a polymer matrix in the solid, liquid or gaseous phase. This book details the thermodynamic principles for selecting these components, their compatibility and their effectiveness. The various mechanisms of metal protection – barrier, inhibiting and electromechanical – are considered, as are the conflicting requirements placed on the structure of the combined material. Two main classes of inhibited materials (structural and films/coatings) are described in detail. Examples are given of structural plastics used in friction units subjected to mechano-chemical wear and of polymer films/coatings for protecting metal objects against corrosion.

  1. Inhibiting the inevitable

    DEFF Research Database (Denmark)

    Shashoua, Yvonne

    2006-01-01

    conservation is to ‘buy time’ for the object. Inhibitive conservation of plastics involves the removal or reduction of factors causing or accelerating degradation including light, oxygen, acids, relative humidity and acidic breakdown products. Specific approaches to conservation have been developed......Once plastics objects are registered in museum collections, the institution becomes responsible for their long term preservation, until the end of their useful lifetime. Plastics appear to deteriorate faster than other materials in museum collections and have a useful lifetime between 5 and 25...... years. Preventive or inhibitive conservation involves controlling the environments in which objects are placed during storage and display, with the aim of slowing the major deterioration reactions. Once in progress, degradation of plastics cannot be stopped or reversed, so the aim of preventive...

  2. Circulating Heat Shock Proteins in Women With a History of Recurrent Vulvovaginitis

    Directory of Open Access Journals (Sweden)

    P. C. Giraldo

    1999-01-01

    70-kDa heat shock proteins (hsp60 and hsp70, respectively in the circulation of women with or without a history of recurrent BV or candidal vaginitis and with or without a current lower genital tract infection. Heat shock protein expression is associated with a down-regulation of proinflammatory immune responses that would inhibit microbial infection.

  3. Cancer Drug-Resistance and a Look at Specific Proteins: Rho GDP-Dissociation Inhibitor 2, Y-Box Binding Protein 1, and HSP70/90 Organizing Protein in Proteomics Clinical Application

    Czech Academy of Sciences Publication Activity Database

    Skalníková, Helena; Martinková, Jiřina; Hrabáková, Rita; Halada, Petr; Dziechciarková, M.; Hajdúch, M.; Gadher, S. J.; Hammar, A.; Enetoft, D.; Ekefjard, A.; Forsstrom-Olsson, O.; Kovářová, Hana

    2011-01-01

    Roč. 10, č. 2 (2011), s. 404-415 ISSN 1535-3893 R&D Projects: GA MŠk LC07017; GA ČR GA301/08/1649 Grant - others:Operational Program Research and Development for Innovations(CZ) CZ.1.05/2.1.00/01.0030 Institutional research plan: CEZ:AV0Z50450515; CEZ:AV0Z50200510 Keywords : cancer * anti-cancer drugs * drug resistance Subject RIV: CE - Biochemistry Impact factor: 5.113, year: 2011

  4. A systematic molecular analysis of the T cell-stimulating antigens from Mycobacterium leprae with T cell clones of leprosy patients. Identification of a novel M. leprae HSP 70 fragment by M. leprae-specific T cells

    NARCIS (Netherlands)

    Janson, A. A.; Klatser, P. R.; van der Zee, R.; Cornelisse, Y. E.; de Vries, R. R.; Thole, J. E.; Ottenhoff, T. H.

    1991-01-01

    Both protective immunity and immunopathology induced by mycobacteria are dependent on Ag-specific, CD4+ MHC class II-restricted T lymphocytes. The identification of Ag recognized by T cells is fundamental to the understanding of protective and pathologic immunity as well as to the design of

  5. Anxiety and retrieval inhibition: support for an enhanced inhibition account.

    Science.gov (United States)

    Nuñez, Mia; Gregory, Josh; Zinbarg, Richard E

    2017-02-01

    Retrieval inhibition of negative associations is important for exposure therapy for anxiety, but the relationship between memory inhibition and anxiety is not well understood-anxiety could either be associated with enhanced or deficient inhibition. The present study tested these two competing hypotheses by measuring retrieval inhibition of negative stimuli by related neutral stimuli. Non-clinically anxious undergraduates completed measures of trait and state anxiety and completed a retrieval induced forgetting task. Adaptive forgetting varied with state anxiety. Low levels of state anxiety were associated with no evidence for retrieval inhibition for either threatening or non-threatening categories. Participants in the middle tertile of state anxiety scores exhibited retrieval inhibition for non-threatening categories but not for threatening categories. Participants in the highest tertile of state anxiety, however, exhibited retrieval inhibition for both threatening and non-threatening categories with the magnitude of retrieval inhibition being greater for threatening than non-threatening categories. The data are in line with the avoidance aspect of the vigilance-avoidance theory of anxiety and inhibition. Implications for cognitive behavioural therapy practices are discussed.

  6. Inhibition of polyphenoloxidase by sulfite

    International Nuclear Information System (INIS)

    Sayavedra-Soto, L.A.; Montgomery, M.W.

    1986-01-01

    When polyphenoloxidase (PPO) was exposed to sulfite prior to substrate addition, inhibition was irreversible. Trials to regenerate PPO activity, using extensive dialysis, column chromatography, and addition of copper salts were not successful. Increased concentrations of sulfite and pH levels less than 5 enhanced the inhibition of PPO by sulfite. At pH 4, concentrations greater than 0.04 mg/mL completely inhibited 1000 units of PPO activity almost instantaneously. This suggested that the HSO 3 - molecule was the main component in the sulfite system inhibiting PPO. Column chromatography, extensive dialysis, and gel electrophoresis did not demonstrate 35 SO 2 bound to purified pear PPO protein. Formation of extra protein bands of sulfite inhibited purified pear PPO fractions on gel electrophoresis was demonstrated. This and other evidence suggested that the major mode of direct irreversible inhibition of PPO was modification of the protein structure, with retention of its molecular unity

  7. Small heat shock proteins potentiate amyloid dissolution by protein disaggregases from yeast and humans.

    Directory of Open Access Journals (Sweden)

    Martin L Duennwald

    Full Text Available How small heat shock proteins (sHsps might empower proteostasis networks to control beneficial prions or disassemble pathological amyloid is unknown. Here, we establish that yeast sHsps, Hsp26 and Hsp42, inhibit prionogenesis by the [PSI+] prion protein, Sup35, via distinct and synergistic mechanisms. Hsp42 prevents conformational rearrangements within molten oligomers that enable de novo prionogenesis and collaborates with Hsp70 to attenuate self-templating. By contrast, Hsp26 inhibits self-templating upon binding assembled prions. sHsp binding destabilizes Sup35 prions and promotes their disaggregation by Hsp104, Hsp70, and Hsp40. In yeast, Hsp26 or Hsp42 overexpression prevents [PSI+] induction, cures [PSI+], and potentiates [PSI+]-curing by Hsp104 overexpression. In vitro, sHsps enhance Hsp104-catalyzed disaggregation of pathological amyloid forms of α-synuclein and polyglutamine. Unexpectedly, in the absence of Hsp104, sHsps promote an unprecedented, gradual depolymerization of Sup35 prions by Hsp110, Hsp70, and Hsp40. This unanticipated amyloid-depolymerase activity is conserved from yeast to humans, which lack Hsp104 orthologues. A human sHsp, HspB5, stimulates depolymerization of α-synuclein amyloid by human Hsp110, Hsp70, and Hsp40. Thus, we elucidate a heretofore-unrecognized human amyloid-depolymerase system that could have applications in various neurodegenerative disorders.

  8. Modeling intentional inhibition of actions

    NARCIS (Netherlands)

    Thilakarathne, D.J.; Treur, J.

    2015-01-01

    Inspired by cognitive and neurological literature on action ownership and action awareness, in this paper a computational cognitive model for intentional inhibition (i.e.; the capacity to voluntarily suspend or inhibit an action) is introduced. The interplay between (positive) potential selection of

  9. Can Arousal Modulate Response Inhibition?

    Science.gov (United States)

    Weinbach, Noam; Kalanthroff, Eyal; Avnit, Amir; Henik, Avishai

    2015-01-01

    The goal of the present study was to examine if and how arousal can modulate response inhibition. Two competing hypotheses can be drawn from previous literature. One holds that alerting cues that elevate arousal should result in an impulsive response and therefore impair response inhibition. The other suggests that alerting enhances processing of…

  10. Selective inhibition of distracting input.

    Science.gov (United States)

    Noonan, MaryAnn P; Crittenden, Ben M; Jensen, Ole; Stokes, Mark G

    2017-10-16

    We review a series of studies exploring distractor suppression. It is often assumed that preparatory distractor suppression is controlled via top-down mechanisms of attention akin to those that prepare brain areas for target enhancement. Here, we consider two alternative mechanisms: secondary inhibition and expectation suppression within a predictive coding framework. We draw on behavioural studies, evidence from neuroimaging and some animal studies. We conclude that there is very limited evidence for selective top-down control of preparatory inhibition. By contrast, we argue that distractor suppression often relies secondary inhibition of non-target items (relatively non-selective inhibition) and on statistical regularities of the environment, learned through direct experience. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.

  11. [Concepts of inhibition in psychiatry].

    Science.gov (United States)

    Auroux, Y; Bourrat, M M; Brun, J P

    1978-01-01

    Following a historical approach, the authors first describe the original development of the concept of inhibition in neurophysiology and then analyze the subsequent adaptations made in psychiatry around such concept including those of: -- Pavlov, Hull, Watson and the behaviorists, -- Freud and the Freudian School, -- clinicians and psychopharmacologists. The concept of inhibition has thus various meanings in psychiatry. Although some unity is achieved on the semiological level, this aspect cannot explain the extent of the process.

  12. Inhibition of MMPs by alcohols

    Science.gov (United States)

    Tezvergil-Mutluay, Arzu; Agee, Kelli A.; Hoshika, Tomohiro; Uchiyama, Toshikazu; Tjäderhane, Leo; Breschi, Lorenzo; Mazzoni, Annalisa; Thompson, Jeremy M.; McCracken, Courtney E.; Looney, Stephen W.; Tay, Franklin R.; Pashley, David H.

    2011-01-01

    Objectives While screening the activity of potential inhibitors of matrix metalloproteinases (MMPs), due to the limited water solubility of some of the compounds, they had to be solubilized in ethanol. When ethanol solvent controls were run, they were found to partially inhibit MMPs. Thus, the purpose of this study was to compare the MMP-inhibitory activity of a series of alcohols. Methods The possible inhibitory activity of a series of alcohols was measured against soluble rhMMP-9 and insoluble matrix-bound endogenous MMPs of dentin in completely demineralized dentin. Increasing concentrations (0.17, 0.86, 1.71 and 4.28 moles/L) of a homologous series of alcohols (i.e. methanol, ethanol, propanols, butanols, pentanols, hexanols, the ethanol ester of methacrylic acid, heptanols and octanol) were compared to ethanediol, and propanediol by regression analysis to calculate the molar concentration required to inhibit MMPs by 50% (i.e. the IC50). Results Using two different MMP models, alcohols were shown to inhibit rhMMP-9 and the endogenous proteases of dentin matrix in a dose-dependent manner. The degree of MMP inhibition by alcohols increased with chain length up to 4 methylene groups. Based on the molar concentration required to inhibit rhMMP-9 fifty percent, 2-hydroxyethylmethacrylate (HEMA), 3-hexanol, 3-heptanol and 1-octanol gave the strongest inhibition. Significance The results indicate that alcohols with 4 methylene groups inhibit MMPs more effectively than methanol or ethanol. MMP inhibition was inversely related to the Hoy's solubility parameter for hydrogen bonding forces of the alcohols (i.e. to their hydrophilicity). PMID:21676453

  13. Geldanamycin induces heat shock protein 70 and protects against MPTP-induced dopaminergic neurotoxicity in mice.

    Science.gov (United States)

    Shen, Hai-Ying; He, Jin-Cai; Wang, Yumei; Huang, Qing-Yuan; Chen, Jiang-Fan

    2005-12-02

    As key molecular chaperone proteins, heat shock proteins (HSPs) represent an important cellular protective mechanism against neuronal cell death in various models of neurological disorders. In this study, we investigated the effect as well as the molecular mechanism of geldanamycin (GA), an inhibitor of Hsp90, on 1-methyl-4-pheny-1,2,3,6-tetrahydropyridine (MPTP)-induced dopaminergic neurotoxicity, a mouse model of Parkinson disease. Neurochemical analysis showed that pretreatment with GA (via intracerebral ventricular injection 24 h prior to MPTP treatment) increased residual dopamine content and tyrosine hydroxylase immunoreactivity in the striatum 24 h after MPTP treatment. To dissect out the molecular mechanism underlying this neuroprotection, we showed that the GA-mediated protection against MPTP was associated with a reduction of cytosolic Hsp90 and an increase in Hsp70, with no significant changes in Hsp40 and Hsp25 levels. Furthermore, in parallel with the induction of Hsp70, striatal nuclear HSF1 levels and HSF1 binding to heat shock element sites in the Hsp70 promoter were significantly enhanced by the GA pretreatment. Together these results suggested that the molecular cascade leading to the induction of Hsp70 is critical to the neuroprotection afforded by GA against MPTP-induced neurotoxicity in the brain and that pharmacological inhibition of Hsp90 may represent a potential therapeutic strategy for Parkinson disease.

  14. Role of Heat Shock Protein 70 in Induction of Stress Fiber Formation in Rat Arterial Endothelial Cells in Response to Stretch Stress

    International Nuclear Information System (INIS)

    Luo, Shan-Shun; Sugimoto, Keiji; Fujii, Sachiko; Takemasa, Tohru; Fu, Song-Bin; Yamashita, Kazuo

    2007-01-01

    We investigated the mechanism by which endothelial cells (ECs) resist various forms of physical stress using an experimental system consisting of rat arterial EC sheets. Formation of actin stress fibers (SFs) and expression of endothelial heat-shock stress proteins (HSPs) in response to mechanical stretch stress were assessed by immunofluorescence microscopy. Stretch stimulation increased expression of HSPs 25 and 70, but not that of HSP 90. Treatment with SB203580, a p38 MAP kinase inhibitor that acts upstream of the HSP 25 activation cascade, or with geldanamycin, an inhibitor of HSP 90, had no effect on the SF formation response to mechanical stretch stress. In contrast, treatment with quercetin, an HSP 70 inhibitor, inhibited both upregulation of endothelial HSP 70 and formation of SFs in response to tensile stress. In addition, treatment of stretched ECs with cytochalasin D, which disrupts SF formation, did not adversely affect stretch-induced upregulation of endothelial HSP 70. Our data suggest that endothelial HSP 70 plays an important role in inducing SF formation in response to tensile stress

  15. Methanol Extract of Myelophycus caespitosus Inhibits the ...

    African Journals Online (AJOL)

    Methanol Extract of Myelophycus caespitosus Inhibits the Inflammatory Response in Lipopolysaccharidestimulated BV2 Microglial Cells by Downregulating NF-kB via Inhibition of the Akt Signaling Pathway.

  16. Homo economicus belief inhibits trust.

    Directory of Open Access Journals (Sweden)

    Ziqiang Xin

    Full Text Available As a foundational concept in economics, the homo economicus assumption regards humans as rational and self-interested actors. In contrast, trust requires individuals to believe partners' benevolence and unselfishness. Thus, the homo economicus belief may inhibit trust. The present three experiments demonstrated that the direct exposure to homo economicus belief can weaken trust. And economic situations like profit calculation can also activate individuals' homo economicus belief and inhibit their trust. It seems that people's increasing homo economicus belief may serve as one cause of the worldwide decline of trust.

  17. Homo Economicus Belief Inhibits Trust

    Science.gov (United States)

    Xin, Ziqiang; Liu, Guofang

    2013-01-01

    As a foundational concept in economics, the homo economicus assumption regards humans as rational and self-interested actors. In contrast, trust requires individuals to believe partners’ benevolence and unselfishness. Thus, the homo economicus belief may inhibit trust. The present three experiments demonstrated that the direct exposure to homo economicus belief can weaken trust. And economic situations like profit calculation can also activate individuals’ homo economicus belief and inhibit their trust. It seems that people’s increasing homo economicus belief may serve as one cause of the worldwide decline of trust. PMID:24146907

  18. Inhibition of Retinoblastoma Protein Inactivation

    Science.gov (United States)

    2017-11-01

    CONTRACT NUMBER Inhibition of Retinoblastoma Protein Inactivation 5b. GRANT NUMBER W81XWH-14-1-0329 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Seth M...confirmed 108 compounds as giving a dose-response curve with at least 30% inhibition at 10 µM. The flowchart of hit progression is shown on the...Cancer Research Program under Award No. W81XWH-14-1-0329 to S.M.R. Opinions, interpretations, conclusions, and recommendations are those of the author

  19. Is forgetting caused by inhibition?

    NARCIS (Netherlands)

    Raaijmakers, J.G.W.; Jakab, E.

    2013-01-01

    A well-known finding in memory research is the forgetting effect that occurs because of practicing some Item A on the recall of a related Item B. The traditional explanation for such interference effects is based on the notion of competition. According to the inhibition theory of forgetting,

  20. Testing of Biologically Inhibiting Surface

    DEFF Research Database (Denmark)

    Bill Madsen, Thomas; Larsen, Erup

    2003-01-01

    The main purpose of this course is to examine a newly developed biologically inhibiting material with regards to galvanic corrosion and electrochemical properties. More in detail, the concern was how the material would react when exposed to cleaning agents, here under CIP cleaning (Cleaning...

  1. Inhibiting cancer cell hallmark features through nuclear export inhibition.

    Science.gov (United States)

    Sun, Qingxiang; Chen, Xueqin; Zhou, Qiao; Burstein, Ezra; Yang, Shengyong; Jia, Da

    2016-01-01

    Treating cancer through inhibition of nuclear export is one of the best examples of basic research translation into clinical application. Nuclear export factor chromosomal region maintenance 1 (CRM1; Xpo1 and exportin-1) controls cellular localization and function of numerous proteins that are critical for the development of many cancer hallmarks. The diverse actions of CRM1 are likely to explain the broad ranging anti-cancer potency of CRM1 inhibitors observed in pre-clinical studies and/or clinical trials (phase I-III) on both advanced-stage solid and hematological tumors. In this review, we compare and contrast the mechanisms of action of different CRM1 inhibitors, and discuss the potential benefit of unexplored non-covalent CRM1 inhibitors. This emerging field has uncovered that nuclear export inhibition is well poised as an attractive target towards low-toxicity broad-spectrum potent anti-cancer therapy.

  2. On inhibition of dental erosion.

    Science.gov (United States)

    Rölla, Gunnar; Jonski, Grazyna; Saxegaard, Erik

    2013-11-01

    To examine the erosion-inhibiting effect of different concentrations of hydrofluoric acid. Thirty-six human molars were individually treated with 10 ml of 0.1 M citric acid for 30 min (Etch 1), acid was collected and stored until analysis. The teeth were randomly divided into six groups and then individually treated with 10 ml of one of six dilutions (from 0.1-1%) of hydrofluoric acid. The teeth were then again treated with citric acid (Etch 2). The individual acid samples from Etch 1 and 2 were analyzed for calcium by flame atomic absorption spectroscopy and difference in calcium loss was calculated. The highest erosion inhibiting effect was obtained in groups with the highest concentrations of hydrofluoric acid, where the pH was lowest, below pKa of 3.17, thus the hydrofluoric acids being mainly in an undissociated state. Diluted hydrofluoric acid is present in aqueous solution of SnF2 and TiF4 (which are known to inhibit dental erosion): SnF2 + 3H2O = Sn(OH)2 + 2HF + H2O and TiF4 + 5H2O = Ti(OH)4 + 4HF + H2O. It is also known that pure, diluted hydrofluoric acid can inhibit dental erosion. Teeth treated with hydrofluoric acid are covered by a layer of CaF2-like mineral. This mineral is acid resistant at pH acid resistant mineral, initiated by tooth enamel treatment with hydrofluoric acid. Hydrofluoric acid is different in having fluoride as a conjugated base, which provides this acid with unique properties.

  3. Entanglement and inhibited quantum evolution

    International Nuclear Information System (INIS)

    Toschek, P E; Balzer, Chr; Hannemann, Th; Wunderlich, Ch; Neuhauser, W

    2003-01-01

    The evolution of a quantum system is impeded by the system's state being observed. A test on an ensemble neither proves the causal nexus nor discloses the nature of the inhibition. Two recent experiments that make use of sequential optical or microwave-optical double resonance on an individual trapped ion disprove a dynamical effect of back action by meter or environment. They rather indicate the ionic states involved in the evolution being entangled with the potentially recorded bivalued scattered-light signal

  4. Hsp90 inhibitor 17-allylamino-17-demethoxygeldanamycin inhibits the proliferation of ARPE-19 cells

    Directory of Open Access Journals (Sweden)

    Wang Lin

    2010-04-01

    Full Text Available Abstract Background The antiproliferative effect of the Hsp90 inhibitor 17-AAG (17-allylamino-17-demethoxygeldanamycin on human retinal pigment epithelial cells is investigated. Methods MTT and flow cytometry were used to study the antiproliferative effects of the 17-AAG treatment of ARPE-19 cells. 2D gel electrophoresis (2-DE and mass spectrometry were applied to detect the altered expression of proteins, which was verified by real-time PCR. Gene Ontology analysis and Ingenuity Pathway Analysis (IPA were utilized to analyze the signaling pathways, cellular location, function, and network connections of the identified proteins. And SOD assay was employed to confirm the analysis. Results 17-AAG suppressed the proliferation of ARPE-19 cells by inducing cell cycle arrest and apoptosis. Proteomic analysis revealed that the expression of 94 proteins was altered by a factor of more than 1.5 following exposure to 17-AAG. Of these 94, 87 proteins were identified. Real-time PCR results indicated that Hsp90 and Hsp70, which were not identified by proteomic analysis, were both upregulated upon 17-AAG treatment. IPA revealed that most of the proteins have functions that are related to oxidative stress, as verified by SOD assay, while canonical pathway analysis revealed glycolysis/gluconeogenesis. Conclusions 17-AAG suppressed the proliferation of ARPE-19 cells by inducing cell cycle arrest and apoptosis, and possibly by oxidative stress.

  5. BAG3-dependent noncanonical autophagy induced by proteasome inhibition in HepG2 cells.

    Science.gov (United States)

    Liu, Bao-Qin; Du, Zhen-Xian; Zong, Zhi-Hong; Li, Chao; Li, Ning; Zhang, Qiang; Kong, De-Hui; Wang, Hua-Qin

    2013-06-01

    Emerging lines of evidence have shown that blockade of ubiquitin-proteasome system (UPS) activates autophagy. The molecular players that regulate the relationship between them remain to be elucidated. Bcl-2 associated athanogene 3 (BAG3) is a member of the BAG co-chaperone family that regulates the ATPase activity of heat shock protein 70 (HSP70) chaperone family. Studies on BAG3 have demonstrated that it plays multiple roles in physiological and pathological processes, including antiapoptotic activity, signal transduction, regulatory role in virus infection, cell adhesion and migration. Recent studies have attracted much attention on its role in initiation of autophagy. The current study, for the first time, demonstrates that proteasome inhibitors elicit noncanonical autophagy, which was not suppressed by inhibitors of class III phosphatidylinositol 3-kinase (PtdIns3K) or shRNA against Beclin 1 (BECN1). In addition, we demonstrate that BAG3 is ascribed to activation of autophagy elicited by proteasome inhibitors and MAPK8/9/10 (also known as JNK1/2/3 respectively) activation is also implicated via upregulation of BAG3. Moreover, we found that noncanonical autophagy mediated by BAG3 suppresses responsiveness of HepG2 cells to proteasome inhibitors.

  6. Inhibition Performance in Children with Math Disabilities

    OpenAIRE

    Winegar, Kathryn Lileth

    2013-01-01

    This study examined the inhibition deficit hypothesis in children with math disabilities (MD). Children with and without MD were compared on two inhibition tasks that included the random generation of numbers and letters. The results addressed three hypotheses. Weak support was found for the first hypothesis which stated difficulties related to inhibition are significantly related to math performance. I found partial support for this hypothesis in that inhibition was related to math problem s...

  7. Entanglement and inhibited quantum evolution

    Energy Technology Data Exchange (ETDEWEB)

    Toschek, P E; Balzer, Chr; Hannemann, Th; Wunderlich, Ch; Neuhauser, W [Universitaet Hamburg, Institut fuer Laser-Physik, Jungiusstrasse 9, D-20355 Hamburg (Germany)

    2003-03-14

    The evolution of a quantum system is impeded by the system's state being observed. A test on an ensemble neither proves the causal nexus nor discloses the nature of the inhibition. Two recent experiments that make use of sequential optical or microwave-optical double resonance on an individual trapped ion disprove a dynamical effect of back action by meter or environment. They rather indicate the ionic states involved in the evolution being entangled with the potentially recorded bivalued scattered-light signal.

  8. Behavioral inhibition and obsessive-compulsive disorder.

    Science.gov (United States)

    Coles, Meredith E; Schofield, Casey A; Pietrefesa, Ashley S

    2006-01-01

    Behavioral inhibition is frequently cited as a vulnerability factor for development of anxiety. However, few studies have examined the unique relationship between behavioral inhibition and obsessive-compulsive disorder (OCD). Therefore, the current study addressed the relationship between behavioral inhibition and OCD in a number of ways. In a large unselected student sample, frequency of current OC symptoms was significantly correlated with retrospective self-reports of total levels of childhood behavioral inhibition. In addition, frequency of current OC symptoms was also significantly correlated with both social and nonsocial components of behavioral inhibition. Further, there was evidence for a unique relationship between behavioral inhibition and OC symptoms beyond the relationship of behavioral inhibition and social anxiety. In addition, results showed that reports of childhood levels of behavioral inhibition significantly predicted levels of OCD symptoms in adulthood. Finally, preliminary evidence suggested that behavioral inhibition may be more strongly associated with some types of OC symptoms than others, and that overprotective parenting may moderate the impact of behavioral inhibition on OC symptoms. The current findings suggest the utility of additional research examining the role of behavioral inhibition in the etiology of OCD.

  9. Self-regulation, ego depletion, and inhibition.

    Science.gov (United States)

    Baumeister, Roy F

    2014-12-01

    Inhibition is a major form of self-regulation. As such, it depends on self-awareness and comparing oneself to standards and is also susceptible to fluctuations in willpower resources. Ego depletion is the state of reduced willpower caused by prior exertion of self-control. Ego depletion undermines inhibition both because restraints are weaker and because urges are felt more intensely than usual. Conscious inhibition of desires is a pervasive feature of everyday life and may be a requirement of life in civilized, cultural society, and in that sense it goes to the evolved core of human nature. Intentional inhibition not only restrains antisocial impulses but can also facilitate optimal performance, such as during test taking. Self-regulation and ego depletion- may also affect less intentional forms of inhibition, even chronic tendencies to inhibit. Broadly stated, inhibition is necessary for human social life and nearly all societies encourage and enforce it. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. Graphene: corrosion-inhibiting coating.

    Science.gov (United States)

    Prasai, Dhiraj; Tuberquia, Juan Carlos; Harl, Robert R; Jennings, G Kane; Rogers, Bridget R; Bolotin, Kirill I

    2012-02-28

    We report the use of atomically thin layers of graphene as a protective coating that inhibits corrosion of underlying metals. Here, we employ electrochemical methods to study the corrosion inhibition of copper and nickel by either growing graphene on these metals, or by mechanically transferring multilayer graphene onto them. Cyclic voltammetry measurements reveal that the graphene coating effectively suppresses metal oxidation and oxygen reduction. Electrochemical impedance spectroscopy measurements suggest that while graphene itself is not damaged, the metal under it is corroded at cracks in the graphene film. Finally, we use Tafel analysis to quantify the corrosion rates of samples with and without graphene coatings. These results indicate that copper films coated with graphene grown via chemical vapor deposition are corroded 7 times slower in an aerated Na(2)SO(4) solution as compared to the corrosion rate of bare copper. Tafel analysis reveals that nickel with a multilayer graphene film grown on it corrodes 20 times slower while nickel surfaces coated with four layers of mechanically transferred graphene corrode 4 times slower than bare nickel. These findings establish graphene as the thinnest known corrosion-protecting coating.

  11. Action inhibition in Tourette syndrome.

    Science.gov (United States)

    Ganos, Christos; Kühn, Simone; Kahl, Ursula; Schunke, Odette; Feldheim, Jan; Gerloff, Christian; Roessner, Veit; Bäumer, Tobias; Thomalla, Götz; Haggard, Patrick; Münchau, Alexander

    2014-10-01

    Tourette syndrome is a neuropsychiatric disorder characterized by tics. Tic generation is often linked to dysfunction of inhibitory brain networks. Some previous behavioral studies found deficiencies in inhibitory motor control in Tourette syndrome, but others suggested normal or even better-than-normal performance. Furthermore, neural correlates of action inhibition in these patients are poorly understood. We performed event-related functional magnetic resonance imaging during a stop-signal reaction-time task in 14 uncomplicated adult Tourette patients and 15 healthy controls. In patients, we correlated activations in stop-signal reaction-time task with their individual motor tic frequency. Task performance was similar in both groups. Activation of dorsal premotor cortex was stronger in the StopSuccess than in the Go condition in healthy controls. This pattern was reversed in Tourette patients. A significant positive correlation was present between motor tic frequency and activations in the supplementary motor area during StopSuccess versus Go in patients. Inhibitory brain networks differ between healthy controls and Tourette patients. In the latter the supplementary motor area is probably a key relay of inhibitory processes mediating both suppression of tics and inhibition of voluntary action. © 2014 International Parkinson and Movement Disorder Society.

  12. STIR: Assessing and Training Response Inhibition Abilities

    Science.gov (United States)

    2014-07-30

    Learning to stop responding to alcohol cues reduces alcohol intake via reduced affective associations rather than increased response inhibition. Addiction ...requires an abstract application of the core learning principle1,2, and viable examples are often hard to find and/or assess. If exposure to non...inhibition training that expands upon previous successful “near transfer” response inhibition training efforts—such as treating alcohol addictions by

  13. Inhibition of cortiocosteroidogenesis by delta-9-tetrahydrocannabinol.

    Science.gov (United States)

    Warner, W; Harris, L S; Carchman, R A

    1977-12-01

    ACTH, cholera toxin, cyclic AMP but not pregnenolone-induced steroidogenesis in Y-1 functional mouse adrenal tumor cells was significantly inhibited by delta-9-tetrahydrocannabinol, cannabidiol, and cannabinol. The inhibition of steroidogenesis could not be correlated with a general depression in cell function or viability. The data suggest that cannabinoids inhibit corticosteroidogenesis at a site between the synthesis of cAMP and of pregnenolone.

  14. Inhibition of apparent photosynthesis by nitrogen oxides

    Energy Technology Data Exchange (ETDEWEB)

    Hill, A C; Bennett, J H

    1970-01-01

    The nitrogen oxides (NO/sub 2/ and NO) inhibited apparent photosynthesis of oats and alfalfa at concentrations below those required to cause visible injury. There appeared to be a threshold concentration of about 0.6 ppm for each pollutant. An additive effect in depressing apparent photosynthesis occurred when the plants were exposed to a mixture of NO and NO/sub 2/. Although NO produced a more rapid effect on the plants, lower concentrations of NO/sub 2/ were required to cause a given inhibition after 2 hour of exposure. Inhibition by nitric oxide was more closely related to its partial pressure than was inhibition by NO/sub 2/.

  15. Inhibition of photosynthesis by carbon monoxide and suspension of the carbon monoxide inhibition by light

    Energy Technology Data Exchange (ETDEWEB)

    Gewitz, H S; Voelker, W

    1963-08-01

    The experimental subject was the autotroph Chlorella pyrenoidosa. It was found that growth conditions determine whether the alga is inhibited by carbon monoxide or not. Respiration and photosynthesis are inhibited by carbon monoxide if the cells have grown rapidly under high light intensities. The inhibition of respiration and photosynthesis found in such cells is completely reversible. The inhibition depends not only on carbon monoxide pressure, but also on the oxygen pressure prevailing at the same time. 5 references, 1 figure, 3 tables.

  16. 7-Piperazinethylchrysin inhibits melanoma cell proliferation by ...

    African Journals Online (AJOL)

    In B16F10 and A375 cells, treatment with PEC caused the inhibition ... Conclusion: PEC inhibited melanoma cell proliferation, apparently by blocking the cell cycle at G0/G1 .... all statistical analyses. .... Financial support from the Department of.

  17. A Qualitative Approach to Enzyme Inhibition

    Science.gov (United States)

    Waldrop, Grover L.

    2009-01-01

    Most general biochemistry textbooks present enzyme inhibition by showing how the basic Michaelis-Menten parameters K[subscript m] and V[subscript max] are affected mathematically by a particular type of inhibitor. This approach, while mathematically rigorous, does not lend itself to understanding how inhibition patterns are used to determine the…

  18. Inhibition: Mental Control Process or Mental Resource?

    Science.gov (United States)

    Im-Bolter, Nancie; Johnson, Janice; Ling, Daphne; Pascual-Leone, Juan

    2015-01-01

    The current study tested 2 models of inhibition in 45 children with language impairment and 45 children with normally developing language; children were aged 7 to 12 years. Of interest was whether a model of inhibition as a mental-control process (i.e., executive function) or as a mental resource would more accurately reflect the relations among…

  19. The pharmacology of visuospatial attention and inhibition

    NARCIS (Netherlands)

    Logemann, H.N.A.

    2013-01-01

    Attention and inhibition are of vital importance in everyday functioning. Problems of attention and inhibition are central to disorders such as Attention Deficit/Hyperactivity Disorder (ADHD). Both bias and disengagement key components of visuospatial attention. Bias refers to neuronal signals that

  20. Inhibition of ethylene production by cobaltous ion

    International Nuclear Information System (INIS)

    Lau, O.L; Yang, S.F.

    1976-01-01

    The effect of Co 2+ on ethylene production by mung bean (Phaseolus aureus Roxb.) and by apple tissues was studied. Co 2+ , depending on concentrations applied, effectively inhibited ethylene production by both tissues. It also strongly inhibited the ethylene production induced by IAA, kinetin, IAA plus kinetin, Ca 2+ , kinetin plus Ca 2+ , or Cu 2+ treatments in mung bean hypocotyl segments. While Co 2+ greatly inhibited ethylene production, it had little effect on the respiration of apple tissue, indicating that Co 2+ does not exert its inhibitory effect as a general metabolic inhibitor. Ni 2+ , which belongs to the same group as Co 2+ in the periodic table, also markedly curtailed both the basal and the induced ethylene production by apple and mung bean hypocotyl tissues. In a system in which kinetin and Ca 2+ were applied together, kinetin greatly enhanced Ca 2+ uptake, thus enhancing ethylene production. Co 2+ , however, slightly inhibited the uptake of Ca 2+ but appreciably inhibited ethylene production, either in the presence or in the absence of kinetin. Tracer experiments using apple tissue indicated that Co 2+ strongly inhibited the in vivo conversion of L-[U-- 14 C]methionine to 14 C-ethylene. These data suggested that Co 2+ inhibited ethylene production by inhibiting the conversion of methionine to ethylene, a common step which is required for ethylene formation by higher plants. Co 2+ is known to promote elongation, leaf expansion, and hook opening in excised plant parts in response to applied auxins or cytokinins.Since ethylene is known to inhibit those growth phenomena, it is suggested that Co 2+ exerts its promotive effect, at least in part, by inhibiting ethylene formation

  1. Therapeutic mechanism of treating SMMC-7721 liver cancer cells with magnetic fluid hyperthermia using Fe{sub 2}O{sub 3} nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Yan, S.Y.; Chen, M.M.; Fan, J.G.; Wang, Y.Q.; Hu, Y.; Xu, L.M., E-mail: leiming.xu@aliyun.com.cn, E-mail: huying@sohu.com [Department of Gastroenterology, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai (China); Du, Y.Q. [Department of Pathology, Cancer Hospital, Fudan University, Shanghai (China)

    2014-11-15

    This study aimed to investigate the therapeutic mechanism of treating SMMC-7721 liver cancer cells with magnetic fluid hyperthermia (MFH) using Fe{sub 2}O{sub 3} nanoparticles. Hepatocarcinoma SMMC-7721 cells cultured in vitro were treated with ferrofluid containing Fe{sub 2}O{sub 3} nanoparticles and irradiated with an alternating radio frequency magnetic field. The influence of the treatment on the cells was examined by inverted microscopy, MTT and flow cytometry. To study the therapeutic mechanism of the Fe{sub 2}O{sub 3} MFH, Hsp70, Bax, Bcl-2 and p53 were detected by immunocytochemistry and reverse transcription polymerase chain reaction (RT-PCR). It was shown that Fe{sub 2}O{sub 3} MFH could cause cellular necrosis, induce cellular apoptosis, and significantly inhibit cellular growth, all of which appeared to be dependent on the concentration of the Fe{sub 2}O{sub 3} nanoparticles. Immunocytochemistry results showed that MFH could induce high expression of Hsp70 and Bax, decrease the expression of mutant p53, and had little effect on Bcl-2. RT-PCR indicated that Hsp70 expression was high in the early stage of MFH (,24 h) and became low or absent after 24 h of MFH treatment. It can be concluded that Fe{sub 2}O{sub 3} MFH significantly inhibited the proliferation of in vitro cultured liver cancer cells (SMMC-7721), induced cell apoptosis and arrested the cell cycle at the G2/M phase. Fe{sub 2}O{sub 3} MFH can induce high Hsp70 expression at an early stage, enhance the expression of Bax, and decrease the expression of mutant p53, which promotes the apoptosis of tumor cells. (author)

  2. Lysophospholipase inhibition by organophosphorus toxicants

    International Nuclear Information System (INIS)

    Quistad, Gary B.; Casida, John E.

    2004-01-01

    Lysophospholipases (LysoPLAs) are a large family of enzymes for removing lysophospholipids from cell membranes. Potent inhibitors are needed to define the importance of LysoPLAs as targets for toxicants and potential therapeutics. This study considers organophosphorus (OP) inhibitors with emphasis on mouse brain total LysoPLA activity relative to the mipafox-sensitive neuropathy target esterase (NTE)-LysoPLA recently established as 17% of the total activity and important in the action of OP delayed toxicants. The most potent inhibitors of total LysoPLA in mouse brain are isopropyl dodecylphosphonofluoridate (also for LysoPLA of Vibrio bacteria), ethyl octylphosphonofluoridate (EOPF), and two alkyl-benzodioxaphosphorin 2-oxides (BDPOs)[(S)-octyl and dodecyl] (IC50 2-8 nM). OP inhibitors acting in vitro and in vivo differentiate a more sensitive portion but not a distinct NTE-LysoPLA compared with total LysoPLA activity. For 10 active inhibitors, NTE-LysoPLA is 17-fold more sensitive than total LysoPLA, but structure-activity comparisons give a good correlation (r 2 = 0.94) of IC50 values, suggesting active site structural similarity or identity. In mice 4 h after intraperitoneal treatment with discriminating doses, EOPF, tribufos (a plant defoliant), and dodecanesulfonyl fluoride inhibit 41-57% of the total brain LysoPLA and 85-99% of the NTE-LysoPLA activity. Total LysoPLA as well as NTE-LysoPLA is decreased in activity in Nte +/- -haploinsufficient mice compared to their Nte +/+ littermates. The lysolecithin level of spinal cord but not brain is elevated significantly following EOPF treatment (3 mg/kg), thereby focusing attention on localized rather than general alterations in lysophospholipid metabolism in OP-induced hyperactivity and toxicity

  3. Regulation of spatial selectivity by crossover inhibition.

    Science.gov (United States)

    Cafaro, Jon; Rieke, Fred

    2013-04-10

    Signals throughout the nervous system diverge into parallel excitatory and inhibitory pathways that later converge on downstream neurons to control their spike output. Converging excitatory and inhibitory synaptic inputs can exhibit a variety of temporal relationships. A common motif is feedforward inhibition, in which an increase (decrease) in excitatory input precedes a corresponding increase (decrease) in inhibitory input. The delay of inhibitory input relative to excitatory input originates from an extra synapse in the circuit shaping inhibitory input. Another common motif is push-pull or "crossover" inhibition, in which increases (decreases) in excitatory input occur together with decreases (increases) in inhibitory input. Primate On midget ganglion cells receive primarily feedforward inhibition and On parasol cells receive primarily crossover inhibition; this difference provides an opportunity to study how each motif shapes the light responses of cell types that play a key role in visual perception. For full-field stimuli, feedforward inhibition abbreviated and attenuated responses of On midget cells, while crossover inhibition, though plentiful, had surprisingly little impact on the responses of On parasol cells. Spatially structured stimuli, however, could cause excitatory and inhibitory inputs to On parasol cells to increase together, adopting a temporal relation very much like that for feedforward inhibition. In this case, inhibitory inputs substantially abbreviated a cell's spike output. Thus inhibitory input shapes the temporal stimulus selectivity of both midget and parasol ganglion cells, but its impact on responses of parasol cells depends strongly on the spatial structure of the light inputs.

  4. Fear inhibition in high trait anxiety.

    Directory of Open Access Journals (Sweden)

    Merel Kindt

    Full Text Available Trait anxiety is recognized as an individual risk factor for the development of anxiety disorders but the neurobiological mechanisms remain unknown. Here we test whether trait anxiety is associated with impaired fear inhibition utilizing the AX+/BX- conditional discrimination procedure that allows for the independent evaluation of startle fear potentiation and inhibition of fear. Sixty undergraduate students participated in the study--High Trait Anxious: n = 28 and Low Trait Anxious: n = 32. We replicated earlier findings that a transfer of conditioned inhibition for startle responses requires contingency awareness. However, contrary to the fear inhibition hypothesis, our data suggest that high trait anxious individuals show a normal fear inhibition of conditioned startle responding. Only at the cognitive level the high trait anxious individuals showed evidence for impaired inhibitory learning of the threat cue. Together with other findings where impaired fear inhibition was only observed in those PTSD patients who were either high on hyperarousal symptoms or with current anxiety symptoms, we question whether impaired fear inhibition is a biomarker for the development of anxiety disorders.

  5. Combined BRAF and HSP90 inhibition in patients with unresectable BRAF V600E mutant melanoma.

    Science.gov (United States)

    Eroglu, Zeynep; Chen, Yian Ann; Gibney, Geoffrey T; Weber, Jeffrey S; Kudchadkar, Ragini R; Khushalani, Nikhil I; Markowitz, Joseph; Brohl, Andrew S; Tetteh, Leticia F; Ramadan, Howida; Arnone, Gina; Li, Jiannong; Zhao, Xiuhua; Sharma, Ritin; Darville, Lancia N F; Fang, Bin; Smalley, Inna; Messina, Jane L; Koomen, John M; Sondak, Vernon K; Smalley, Keiran S M

    2018-04-19

    BRAF inhibitors are clinically active in patients with advanced BRAF V600 -mutant melanoma, although acquired resistance remains common. Preclinical studies demonstrated that resistance could be overcome using concurrent treatment with the HSP90 inhibitor XL888. Vemurafenib (960 mg PO BID) combined with escalating doses of XL888 (30, 45, 90 or 135 mg PO twice weekly) was investigated in 21 patients with advanced BRAF V600 -mutant melanoma. Primary endpoints were safety and determination of a maximum tolerated dose. Correlative proteomic studies were performed to confirm HSP inhibitor activity. Objective responses were observed in 15/20 evaluable patients (75%; 95% CI: 51-91%), with 3 complete and 12 partial responses. Median progression-free and overall survival were 9.2 months (95% CI: 3.8-not reached) and 34.6 months (6.2-not reached), respectively. The most common grade 3/4 toxicities were skin toxicities such as rash (n=4, 19%) and cutaneous squamous cell carcinomas (n=3, 14%), along with diarrhea (n=3, 14%). Pharmacodynamic analysis of patients' PBMCs showed increased day 8 HSP70 expression compared to baseline in the three cohorts with XL888 doses ≥45 mg. Diverse effects of vemurafenib-XL888 upon intratumoral HSP-client protein expression were noted, with the expression of multiple proteins (including ERBB3 and BAD) modulated on therapy. XL888 in combination with vemurafenib has clinical activity in patients with advanced BRAF V600 -mutant melanoma, with a tolerable side-effect profile. HSP90 inhibitors warrant further evaluation in combination with current standard-of-care BRAF plus MEK inhibitors in BRAF V600 -mutant melanoma. Copyright ©2018, American Association for Cancer Research.

  6. Caloric restriction induces heat shock response and inhibits B16F10 cell tumorigenesis both in vitro and in vivo

    Science.gov (United States)

    Novelle, Marta G.; Davis, Ashley; Price, Nathan L.; Ali, Ahmed; Fürer-Galvan, Stefanie; Zhang, Yongqing; Becker, Kevin; Bernier, Michel; de Cabo, Rafael

    2015-01-01

    Caloric restriction (CR) without malnutrition is one of the most consistent strategies for increasing mean and maximal lifespan and delaying the onset of age-associated diseases. Stress resistance is a common trait of many long-lived mutants and life-extending interventions, including CR. Indeed, better protection against heat shock and other genotoxic insults have helped explain the pro-survival properties of CR. In this study, both in vitro and in vivo responses to heat shock were investigated using two different models of CR. Murine B16F10 melanoma cells treated with serum from CR-fed rats showed lower proliferation, increased tolerance to heat shock and enhanced HSP-70 expression, compared to serum from ad libitum-fed animals. Similar effects were observed in B16F10 cells implanted subcutaneously in male C57BL/6 mice subjected to CR. Microarray analysis identified a number of genes and pathways whose expression profile were similar in both models. These results suggest that the use of an in vitro model could be a good alternative to study the mechanisms by which CR exerts its anti-tumorigenic effects. PMID:25948793

  7. Should we stop thinking about inhibition? Searching for individual and age differences in inhibition ability.

    Science.gov (United States)

    Rey-Mermet, Alodie; Gade, Miriam; Oberauer, Klaus

    2018-04-01

    Inhibition is often conceptualized as a unitary construct reflecting the ability to ignore and suppress irrelevant information. At the same time, it has been subdivided into inhibition of prepotent responses (i.e., the ability to stop dominant responses) and resistance to distracter interference (i.e., the ability to ignore distracting information). The present study investigated the unity and diversity of inhibition as a psychometric construct, and tested the hypothesis of an inhibition deficit in older age. We measured inhibition in young and old adults with 11 established laboratory tasks: antisaccade, stop-signal, color Stroop, number Stroop, arrow flanker, letter flanker, Simon, global-local, positive and negative compatibility tasks, and n-2 repetition costs in task switching. In both age groups, the inhibition measures from individual tasks had good reliabilities, but correlated only weakly among each other. Structural equation modeling identified a 2-factor model with factors for inhibition of prepotent responses and resistance to distracter interference. Older adults scored worse in the inhibition of prepotent response, but better in the resistance to distracter interference. However, the model had low explanatory power. Together, these findings call into question inhibition as a psychometric construct and the hypothesis of an inhibition deficit in older age. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

  8. Inhibition of urinary calculi -- a spectroscopic study

    Science.gov (United States)

    Manciu, Felicia; Govani, Jayesh; Durrer, William; Reza, Layra; Pinales, Luis

    2008-10-01

    Although a considerable number of investigations have already been undertaken and many causes such as life habits, metabolic disorders, and genetic factors have been noted as sources that accelerate calculi depositions and aggregations, there are still plenty of unanswered questions regarding efficient inhibition and treatment mechanisms. Thus, in an attempt to acquire more insights, we propose here a detailed scientific study of kidney stone formation and growth inhibition based on a traditional medicine approach with Rotula Aquatica Lour (RAL) herbal extracts. A simplified single diffusion gel growth technique was used for synthesizing the samples for the present study. The unexpected Zn presence in the sample with RAL inhibitor, as revealed by XPS measurements, explains the inhibition process and the dramatic reflectance of the incident light observed in the infrared transmission studies. Raman data demonstrate potential binding of the inhibitor with the oxygen of the kidney stone. Photoluminescence results corroborate to provide additional evidence of Zn-related inhibition.

  9. Exogenously triggered response inhibition in developmental stuttering.

    Science.gov (United States)

    Eggers, Kurt; De Nil, Luc F; Van den Bergh, Bea R H

    2018-06-01

    The purpose of the present study was to examine relations between children's exogenously triggered response inhibition and stuttering. Participants were 18 children who stutter (CWS; mean age = 9;01 years) and 18 children who not stutter (CWNS; mean age = 9;01 years). Participants were matched on age (±3 months) and gender. Response inhibition was assessed by a stop signal task (Verbruggen, Logan, & Stevens, 2008). Results suggest that CWS, compared to CWNS, perform comparable to CWNS in a task where response control is externally triggered. Our findings seem to indicate that previous questionnaire-based findings (Eggers, De Nil, & Van den Bergh, 2010) of a decreased efficiency of response inhibition cannot be generalized to all types of response inhibition. Copyright © 2018 Elsevier Inc. All rights reserved.

  10. Hypnotic suggestibility, cognitive inhibition, and dissociation.

    Science.gov (United States)

    Dienes, Zoltán; Brown, Elizabeth; Hutton, Sam; Kirsch, Irving; Mazzoni, Giuliana; Wright, Daniel B

    2009-12-01

    We examined two potential correlates of hypnotic suggestibility: dissociation and cognitive inhibition. Dissociation is the foundation of two of the major theories of hypnosis and other theories commonly postulate that hypnotic responding is a result of attentional abilities (including inhibition). Participants were administered the Waterloo-Stanford Group Scale of Hypnotic Susceptibility, Form C. Under the guise of an unrelated study, 180 of these participants also completed: a version of the Dissociative Experiences Scale that is normally distributed in non-clinical populations; a latent inhibition task, a spatial negative priming task, and a memory task designed to measure negative priming. The data ruled out even moderate correlations between hypnotic suggestibility and all the measures of dissociation and cognitive inhibition overall, though they also indicated gender differences. The results are a challenge for existing theories of hypnosis.

  11. Corrosion inhibition by lithium zinc phosphate pigment

    International Nuclear Information System (INIS)

    Alibakhshi, E.; Ghasemi, E.; Mahdavian, M.

    2013-01-01

    Highlights: •Synthesis of lithium zinc phosphate (LZP) by chemical co-precipitation method. •Corrosion inhibition activity of pigments compare with zinc phosphate (ZP). •LZP showed superior corrosion inhibition effect in EIS measurements. •Evaluation of adhesion strength and dispersion stability. -- Abstract: Lithium zinc phosphate (LZP) has been synthesized through a co-precipitation process and characterized by XRD and IR spectroscopy. The inhibitive performances of this pigment for corrosion of mild steel have been discussed in comparison with the zinc phosphate (ZP) in the pigment extract solution by means of EIS and in the epoxy coating by means of salt spray. The EIS and salt spray results revealed the superior corrosion inhibitive effect of LZP compared to ZP. Moreover, adhesion strength and dispersion stability of the pigmented epoxy coating showed the advantage of LZP compared to ZP

  12. Human milk glycoconjugates that inhibit pathogens.

    Science.gov (United States)

    Newburg, D S

    1999-02-01

    Breast-fed infants have lower incidence of diarrhea, respiratory disease, and otitis media. The protection by human milk has long been attributed to the presence of secretory IgA. However, human milk contains large numbers and amounts of complex carbohydrates, including glycoproteins, glycolipids, glycosaminoglycans, mucins, and especially oligosaccharides. The oligosaccharides comprise the third most abundant solid constituent of human milk, and contain a myriad of structures. Complex carbohydrate moieties of glycoconjugates and oligosaccharides are synthesized by the many glycosyltransferases in the mammary gland; those with homology to cell surface glycoconjugate pathogen receptors may inhibit pathogen binding, thereby protecting the nursing infant. Several examples are reviewed: A fucosyloligosaccharide inhibits the diarrheagenic effect of stable toxin of Escherichia coli. A different fucosyloligosaccharide inhibits infection by Campylobacter jejuni. Binding of Streptococcus pneumoniae and of enteropathogenic E. coli to their respective receptors is inhibited by human milk oligosaccharides. The 46-kD glycoprotein, lactadherin, inhibits rotavirus binding and infectivity. Low levels of lactadherin in human milk are associated with a higher incidence of symptomatic rotavirus in breast-fed infants. A mannosylated glycopeptide inhibits binding by enterohemorrhagic E. coli. A glycosaminoglycan inhibits binding of gp120 to CD4, the first step in HIV infection. Human milk mucin inhibits binding by S-fimbriated E. coli. The ganglioside, GM1, reduces diarrhea production by cholera toxin and labile toxin of E. coli. The neutral glycosphingolipid, Gb3, binds to Shigatoxin. Thus, many complex carbohydrates of human milk may be novel antipathogenic agents, and the milk glycoconjugates and oligosaccharides may be a major source of protection for breastfeeding infants.

  13. Inhibition in the Human Auditory Cortex.

    Directory of Open Access Journals (Sweden)

    Koji Inui

    Full Text Available Despite their indispensable roles in sensory processing, little is known about inhibitory interneurons in humans. Inhibitory postsynaptic potentials cannot be recorded non-invasively, at least in a pure form, in humans. We herein sought to clarify whether prepulse inhibition (PPI in the auditory cortex reflected inhibition via interneurons using magnetoencephalography. An abrupt increase in sound pressure by 10 dB in a continuous sound was used to evoke the test response, and PPI was observed by inserting a weak (5 dB increase for 1 ms prepulse. The time course of the inhibition evaluated by prepulses presented at 10-800 ms before the test stimulus showed at least two temporally distinct inhibitions peaking at approximately 20-60 and 600 ms that presumably reflected IPSPs by fast spiking, parvalbumin-positive cells and somatostatin-positive, Martinotti cells, respectively. In another experiment, we confirmed that the degree of the inhibition depended on the strength of the prepulse, but not on the amplitude of the prepulse-evoked cortical response, indicating that the prepulse-evoked excitatory response and prepulse-evoked inhibition reflected activation in two different pathways. Although many diseases such as schizophrenia may involve deficits in the inhibitory system, we do not have appropriate methods to evaluate them; therefore, the easy and non-invasive method described herein may be clinically useful.

  14. Evidence-based efficacy of adaptogens in fatigue, and molecular mechanisms related to their stress-protective activity.

    Science.gov (United States)

    Panossian, Alexander; Wikman, Georg

    2009-09-01

    The aim of this review article is to assess the level of scientific evidence presented by clinical trials of adaptogens in fatigue, and to provide a rationale at the molecular level for verified effects. Strong scientific evidence is available for Rhodiola rosea SHR-5 extract, which improved attention, cognitive function and mental performance in fatigue and in chronic fatigue syndrome. Good scientific evidence has been documented in trails in which Schisandra chinensis and Eleutherococcus senticosus increased endurance and mental performance in patients with mild fatigue and weakness. Based on their efficacy in clinical studies, adaptogens can be defined as a pharmacological group of herbal preparations that increase tolerance to mental exhaustion and enhance attention and mental endurance in situations of decreased performance. The beneficial stress-protective effect of adaptogens is related to regulation of homeostasis via several mechanisms of action associated with the hypothalamic-pituitary-adrenal axis and the control of key mediators of stress response such as molecular chaperons (e.g. Hsp70), stress-activated c-Jun N-terminal protein kinase (JNK1), Forkhead Box O transcription factor DAF-16, cortisol and nitric oxide (NO). The key point of action of phytoadaptogens appears to be their up-regulating and stress-mimetic effects on the "stress-sensor" protein Hsp70, which plays an important role in cell survival and apoptosis. Hsp70 inhibits the expression of NO synthase II gene and interacts with glucocorticoid receptors directly and via the JNK pathway, thus affecting the levels of circulating cortisol and NO. Prevention of stress-induced increase in NO, and the associated decrease in ATP production, results in increased performance and endurance. Adaptogen-induced up-regulation of Hsp70 triggers stress-induced JNK-1 and DAF-16-mediated pathways regulating the resistance to stress and resulting in enhanced mental and physical performance and, possibly

  15. The Role of the Heat Shock Protein B8 (HSPB8 in Motoneuron Diseases

    Directory of Open Access Journals (Sweden)

    Paola Rusmini

    2017-06-01

    Full Text Available Amyotrophic lateral sclerosis (ALS and spinal and bulbar muscular atrophy (SBMA are two motoneuron diseases (MNDs characterized by aberrant protein behavior in affected cells. In familial ALS (fALS and in SBMA specific gene mutations lead to the production of neurotoxic proteins or peptides prone to misfold, which then accumulate in form of aggregates. Notably, some of these proteins accumulate into aggregates also in sporadic ALS (sALS even if not mutated. To prevent proteotoxic stresses detrimental to cells, misfolded and/or aggregated proteins must be rapidly removed by the protein quality control (PQC system. The small heat shock protein B8 (HSPB8 is a chaperone induced by harmful events, like proteasome inhibition. HSPB8 is expressed both in motoneuron and muscle cells, which are both targets of misfolded protein toxicity in MNDs. In ALS mice models, in presence of the mutant proteins, HSPB8 is upregulated both in spinal cord and muscle. HSPB8 interacts with the HSP70 co-chaperone BAG3 and enhances the degradation of misfolded proteins linked to sALS, or causative of fALS and of SBMA. HSPB8 acts by facilitating autophagy, thereby preventing misfolded protein accumulation in affected cells. BAG3 and BAG1 compete for HSP70-bound clients and target them for disposal to the autophagy or proteasome, respectively. Enhancing the selective targeting of misfolded proteins by HSPB8-BAG3-HSP70 to autophagy may also decrease their delivery to the proteasome by the BAG1-HSP70 complex, thereby limiting possible proteasome overwhelming. Thus, approaches aimed at potentiating HSPB8-BAG3 may contribute to the maintenance of proteostasis and may delay MNDs progression.

  16. Nitric oxide mediates the stress response induced by diatom aldehydes in the sea urchin Paracentrotus lividus.

    Directory of Open Access Journals (Sweden)

    Giovanna Romano

    Full Text Available Diatoms are ubiquitous and abundant primary producers that have been traditionally considered as a beneficial food source for grazers and for the transfer of carbon through marine food webs. However, many diatom species produce polyunsaturated aldehydes that disrupt development in the offspring of grazers that feed on these unicellular algae. Here we provide evidence that production of the physiological messenger nitric oxide increases after treatment with the polyunsaturated aldehyde decadienal in embryos of the sea urchin Paracentrotus lividus. At high decadienal concentrations, nitric oxide mediates initial apoptotic events leading to loss of mitochondrial functionality through the generation of peroxynitrite. At low decadienal concentrations, nitric oxide contributes to the activation of hsp70 gene expression thereby protecting embryos against the toxic effects of this aldehyde. When nitric oxide levels were lowered by inhibiting nitric oxide synthase activity, the expression of hsp70 in swimming blastula decreased and the proportion of abnormal plutei increased. However, in later pluteus stages nitric oxide was no longer able to exert this protective function: hsp70 and nitric oxide synthase expression decreased with a consequent increase in the expression of caspase-8. Our findings that nitric oxide production increases rapidly in response to a toxic exogenous stimulus opens new perspectives on the possible role of this gas as an important messenger to environmental stress in sea urchins and for understanding the cellular mechanisms underlying toxicity during diatom blooms.

  17. Regulation of human heme oxygenase-1 gene expression under thermal stress.

    Science.gov (United States)

    Okinaga, S; Takahashi, K; Takeda, K; Yoshizawa, M; Fujita, H; Sasaki, H; Shibahara, S

    1996-06-15

    Heme oxygenase-1 is an essential enzyme in heme catabolism, and its human gene promoter contains a putative heat shock element (HHO-HSE). This study was designed to analyze the regulation of human heme oxygenase-1 gene expression under thermal stress. The amounts of heme oxygenase-1 protein were not increased by heat shock (incubation at 42 degrees C) in human alveolar macrophages and in a human erythroblastic cell line, YN-1-0-A, whereas heat shock protein 70 (HSP70) was noticeably induced. However, heat shock factor does bind in vitro to HHO-HSE and the synthetic HHO-HSE by itself is sufficient to confer the increase in the transient expression of a reporter gene upon heat shock. The deletion of the sequence, located downstream from HHO-HSE, resulted in the activation of a reporter gene by heat shock. These results suggest that HHO-HSE is potentially functional but is repressed in vivo. Interestingly, heat shock abolished the remarkable increase in the levels of heme oxygenase-1 mRNA in YN-1-0-A cells treated with hemin or cadmium, in which HSP70 mRNA was noticeably induced. Furthermore, transient expression assays showed that heat shock inhibits the cadmium-mediated activation of the heme oxygenase-1 promoter, whereas the HSP70 gene promoter was activated upon heat shock. Such regulation of heme oxygenase-1 under thermal stress may be of physiologic significance in erythroid cells.

  18. Involvement of apoptosis in host-parasite interactions in the zebra mussel.

    Directory of Open Access Journals (Sweden)

    Laëtitia Minguez

    Full Text Available The question of whether cell death by apoptosis plays a biological function during infection is key to understanding host-parasite interactions. We investigated the involvement of apoptosis in several host-parasite systems, using zebra mussels Dreissena polymorpha as test organisms and their micro- and macroparasites. As a stress response associated with parasitism, heat shock proteins (Hsp can be induced. In this protein family, Hsp70 are known to be apoptosis inhibitors. Mussels were diagnosed for their respective infections by standard histological methods; apoptosis was detected using the TUNEL methods on paraffin sections and Hsp70 by immunohistochemistry on cryosections. Circulating hemocytes were the main cells observed in apoptosis whereas infected tissues displayed no or few apoptotic cells. Parasitism by intracellular bacteria Rickettsiales-like and the trematode Bucephalus polymorphus were associated with the inhibition of apoptosis whereas ciliates Ophryoglena spp. or the trematode Phyllodistomum folium did not involve significant differences in apoptosis. Even if some parasites were able to modulate apoptosis in zebra mussels, we did not see evidence of any involvement of Hsp70 on this mechanism.

  19. Involvement of Apoptosis in Host-Parasite Interactions in the Zebra Mussel

    Science.gov (United States)

    Minguez, Laëtitia; Brulé, Nelly; Sohm, Bénédicte; Devin, Simon; Giambérini, Laure

    2013-01-01

    The question of whether cell death by apoptosis plays a biological function during infection is key to understanding host-parasite interactions. We investigated the involvement of apoptosis in several host-parasite systems, using zebra mussels Dreissena polymorpha as test organisms and their micro- and macroparasites. As a stress response associated with parasitism, heat shock proteins (Hsp) can be induced. In this protein family, Hsp70 are known to be apoptosis inhibitors. Mussels were diagnosed for their respective infections by standard histological methods; apoptosis was detected using the TUNEL methods on paraffin sections and Hsp70 by immunohistochemistry on cryosections. Circulating hemocytes were the main cells observed in apoptosis whereas infected tissues displayed no or few apoptotic cells. Parasitism by intracellular bacteria Rickettsiales-like and the trematode Bucephalus polymorphus were associated with the inhibition of apoptosis whereas ciliates Ophryoglena spp. or the trematode Phyllodistomum folium did not involve significant differences in apoptosis. Even if some parasites were able to modulate apoptosis in zebra mussels, we did not see evidence of any involvement of Hsp70 on this mechanism. PMID:23785455

  20. Characterization of acetylcholinesterase-inhibition by itopride.

    Science.gov (United States)

    Iwanaga, Y; Kimura, T; Miyashita, N; Morikawa, K; Nagata, O; Itoh, Z; Kondo, Y

    1994-11-01

    Itopride is a gastroprokinetic benzamide derivative. This agent inhibited both electric eel acetylcholinesterase (AChE) and horse serum butyrylcholinesterase (BuChE). The IC50 of itopride with AChE (2.04 +/- 0.27 microM) was, however, 100-fold less than that with BuChE, whereas in the case of neostigmine with AChE (11.3 +/- 3.4 nM), it was 10-fold less. The recovery of AChE activity inhibited by 10(-7) M neostigmine was partial, but that inhibited by up to 3 x 10(-5) M itopride was complete when the reaction mixture was subjected to ultrafiltration. Double reciprocal plots of the experimental data showed that both Km and Vmax were affected by itopride, suggesting that the inhibition is a "mixed" type, although primarily being an uncompetitive one. The inhibitory effect of itopride on cholinesterase (ChE) activity in guinea pig gastrointestine was much weaker than that on pure AChE. However, in the presence of a low dose of diisopropyl fluorophosphate, just enough to inhibit BuChE but not AChE, the IC50s of itopride against ChE activities were found to be about 0.5 microM. In conclusion, itopride exerts reversible and a "mixed" type of inhibition preferably against AChE. The IC50 of itopride for electric eel and guinea pig gastrointestinal AChE inhibition was 200 times and 50 times as large as that of neostigmine, respectively.

  1. Molecular characterization of three heat shock protein 70 genes and their expression profiles under thermal stress in the citrus red mite.

    Science.gov (United States)

    Yang, Li-Hong; Jiang, Hong-Bo; Liu, Yong-Hua; Dou, Wei; Wang, Jin-Jun

    2012-04-01

    Three heat shock protein 70 family transcripts, named PcHsp70-1, PcHsp70-2 and PcHsp70-3, were isolated from the citrus red mite, Panonychus citri. PcHsp70-1, PcHsp70-2, and PcHsp70-3 contained an open reading frame of 1977, 1968, and 2028 nucleotides that encoded 658, 655 and 675 amino acid residues, respectively. Comparison of deduced amino acid sequences of PcHsp70-1 and PcHsp70-2 showed 86.34% identity, while the amino acid sequence of PcHsp70-3 was only 57.39 and 58.75% identical to that of PcHsp70-1 and PcHsp70-2, respectively. Sequences and phylogenetic analyses suggested that PcHsp70-1 and PcHsp70-2 were cytosolic Hsps, whereas PcHsp70-3 was located in ER (endoplasmic reticulum). To accurately validate mRNA expression profiles of the three Hsp70s under thermal stress conditions, seven housekeeping genes were evaluated. Alpha-tubulin and RpII were selected as optimal endogenous references for cold shock and heat shock conditions, respectively. Real-time quantitative RT-PCR revealed that only the mRNA expression of PcHsp70-2 was up-regulated under heat shocks, and all of the three Hsp70s were constitutively expressed under cold shocks. The results suggest that the three Hsp70s were more critical to coping with heat than cold shocks.

  2. Aspartate inhibits Staphylococcus aureus biofilm formation.

    Science.gov (United States)

    Yang, Hang; Wang, Mengyue; Yu, Junping; Wei, Hongping

    2015-04-01

    Biofilm formation renders Staphylococcus aureus highly resistant to conventional antibiotics and host defenses. Four D-amino acids (D-Leu, D-Met, D-Trp and D-Tyr) have been reported to be able to inhibit biofilm formation and disassemble established S. aureus biofilms. We report here for the first time that both D- and L-isoforms of aspartate (Asp) inhibited S. aureus biofilm formation on tissue culture plates. Similar biofilm inhibition effects were also observed against other staphylococcal strains, including S. saprophyticus, S. equorum, S. chromogenes and S. haemolyticus. It was found that Asp at high concentrations (>10 mM) inhibited the growth of planktonic N315 cells, but at subinhibitory concentrations decreased the cellular metabolic activity without influencing cell growth. The decreased cellular metabolic activity might be the reason for the production of less protein and DNA in the matrix of the biofilms formed in the presence of Asp. However, varied inhibition efficacies of Asp were observed for biofilms formed by clinical staphylococcal isolates. There might be mechanisms other than decreasing the metabolic activity, e.g. the biofilm phenotypes, affecting biofilm formation in the presence of Asp. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  3. Simvastatin inhibits Candida albicans biofilm in vitro.

    Science.gov (United States)

    Liu, Geoffrey; Vellucci, Vincent F; Kyc, Stephanie; Hostetter, Margaret K

    2009-12-01

    By inhibiting the conversion of 3-hydroxy-3-methylglutaryl CoA (HMG-CoA) to mevalonate, statins impair cholesterol metabolism in humans. We reasoned that statins might similarly interfere with the biosynthesis of ergosterol, the major sterol of the yeast cell membrane. As assessed by spectrophotometric and microscopic analysis, significant inhibition of biofilm production was noted after 16-h incubation with 1, 2.5, and 5 muM simvastatin, concentrations that did not affect growth, adhesion, or hyphal formation by C. albicans in vitro. Higher concentrations (10, 20, and 25 muM simvastatin) inhibited biofilm by >90% but also impaired growth. Addition of exogenous ergosterol (90 muM) overcame the effects of 1 and 2.5 muM simvastatin, suggesting that at least one mechanism of inhibition is interference with ergosterol biosynthesis. Clinical isolates from blood, skin, and mucosal surfaces produced biofilms; biofilms from bloodstream isolates were similarly inhibited by simvastatin. In the absence of fungicidal activity, simvastatin's interruption of a critical step in an essential metabolic pathway, highly conserved from yeast to man, has unexpected effects on biofilm production by a eukaryotic pathogen.

  4. Terbinafine inhibits gap junctional intercellular communication

    International Nuclear Information System (INIS)

    Lee, Ju Yeun; Yoon, Sei Mee; Choi, Eun Ju; Lee, Jinu

    2016-01-01

    Terbinafine is an antifungal agent that selectively inhibits fungal sterol synthesis by blocking squalene epoxidase. We evaluated the effect of terbinafine on gap junctional intercellular communication (GJIC). Fluorescence recovery after photobleaching (FRAP) and I-YFP GJIC assays revealed that terbinafine inhibits GJIC in a reversible and dose-dependent manner in FRT-Cx43 and LN215 cells. Treatment with terbinafine did not affect Cx43 phosphorylation status or intracellular Ca 2+ concentration, well-known action mechanisms of various GJIC blockers. While a structurally related chemical, naftifine, attenuated GJIC, epigallocatechin gallate, another potent squalene epoxidase inhibitor with a different structure, did not. These results suggest that terbinafine inhibits GJIC with a so far unknown mechanism of action. - Highlights: • In vitro pharmacological studies were performed on FRT-Cx43 and LN215 cells. • Terbinafine inhibits gap junctional intercellular communication in both cell lines. • The inhibitory effect of terbinafine is reversible and dose-dependent. • Treatment of terbinafine does not alter Cx43 phosphorylation or cytosolic Ca 2+ concentration. • Inhibition of squalene epoxidase is not involved in this new effect of terbinafine.

  5. Terbinafine inhibits gap junctional intercellular communication

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Ju Yeun, E-mail: whitewndus@naver.com [College of Pharmacy, Yonsei Institute of Pharmaceutical Sciences, Yonsei University, 85 Songdogwahak-ro, Yeonsu-gu, Incheon 21983 (Korea, Republic of); Yoon, Sei Mee, E-mail: sei_mee@naver.com [College of Pharmacy, Yonsei Institute of Pharmaceutical Sciences, Yonsei University, 85 Songdogwahak-ro, Yeonsu-gu, Incheon 21983 (Korea, Republic of); Department of Integrated OMICS for Biomedical Sciences, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 120-749 (Korea, Republic of); Choi, Eun Ju, E-mail: yureas@naver.com [College of Pharmacy, Yonsei Institute of Pharmaceutical Sciences, Yonsei University, 85 Songdogwahak-ro, Yeonsu-gu, Incheon 21983 (Korea, Republic of); Lee, Jinu, E-mail: jinulee@yonsei.ac.kr [College of Pharmacy, Yonsei Institute of Pharmaceutical Sciences, Yonsei University, 85 Songdogwahak-ro, Yeonsu-gu, Incheon 21983 (Korea, Republic of)

    2016-09-15

    Terbinafine is an antifungal agent that selectively inhibits fungal sterol synthesis by blocking squalene epoxidase. We evaluated the effect of terbinafine on gap junctional intercellular communication (GJIC). Fluorescence recovery after photobleaching (FRAP) and I-YFP GJIC assays revealed that terbinafine inhibits GJIC in a reversible and dose-dependent manner in FRT-Cx43 and LN215 cells. Treatment with terbinafine did not affect Cx43 phosphorylation status or intracellular Ca{sup 2+} concentration, well-known action mechanisms of various GJIC blockers. While a structurally related chemical, naftifine, attenuated GJIC, epigallocatechin gallate, another potent squalene epoxidase inhibitor with a different structure, did not. These results suggest that terbinafine inhibits GJIC with a so far unknown mechanism of action. - Highlights: • In vitro pharmacological studies were performed on FRT-Cx43 and LN215 cells. • Terbinafine inhibits gap junctional intercellular communication in both cell lines. • The inhibitory effect of terbinafine is reversible and dose-dependent. • Treatment of terbinafine does not alter Cx43 phosphorylation or cytosolic Ca{sup 2+} concentration. • Inhibition of squalene epoxidase is not involved in this new effect of terbinafine.

  6. Inhibition of ethylene production by putrescine alleviates aluminium-induced root inhibition in wheat plants.

    Science.gov (United States)

    Yu, Yan; Jin, Chongwei; Sun, Chengliang; Wang, Jinghong; Ye, Yiquan; Zhou, Weiwei; Lu, Lingli; Lin, Xianyong

    2016-01-08

    Inhibition of root elongation is one of the most distinct symptoms of aluminium (Al) toxicity. Although putrescine (Put) has been identified as an important signaling molecule involved in Al tolerance, it is yet unknown how Put mitigates Al-induced root inhibition. Here, the possible mechanism was investigated by using two wheat genotypes differing in Al resistance: Al-tolerant Xi Aimai-1 and Al-sensitive Yangmai-5. Aluminium caused more root inhibition in Yangmai-5 and increased ethylene production at the root apices compared to Xi Aimai-1, whereas the effects were significantly reversed by ethylene biosynthesis inhibitors. The simultaneous exposure of wheat seedlings to Al and ethylene donor, ethephon, or ethylene biosynthesis precursor, 1-aminocyclopropane-1-carboxylic acid (ACC), increased ethylene production and aggravated root inhibition, which was more pronounced in Xi Aimai-1. In contrast, Put treatment decreased ethylene production and alleviated Al-induced root inhibition in both genotypes, and the effects were more conspicuous in Yangmai-5. Furthermore, our results indicated that Al-induced ethylene production was mediated by ACC synthase (ACS) and ACC oxidase, and that Put decreased ethylene production by inhibiting ACS. Altogether, these findings indicate that ethylene is involved in Al-induced root inhibition and this process could be alleviated by Put through inhibiting ACS activity.

  7. Silver-Palladium Surfaces Inhibit Biofilm Formation

    DEFF Research Database (Denmark)

    Chiang, Wen-Chi; Schroll, Casper; Hilbert, Lisbeth Rischel

    2009-01-01

    Undesired biofilm formation is a major concern in many areas. In the present study, we investigated biofilm-inhibiting properties of a silver-palladium surface that kills bacteria by generating microelectric fields and electrochemical redox processes. For evaluation of the biofilm inhibition...... efficacy and study of the biofilm inhibition mechanism, the silver-sensitive Escherichia coli J53 and the silver-resistant E. coli J53[pMG101] strains were used as model organisms, and batch and flow chamber setups were used as model systems. In the case of the silver-sensitive strain, the silver......-palladium surfaces killed the bacteria and prevented biofilm formation under conditions of low or high bacterial load. In the case of the silver-resistant strain, the silver-palladium surfaces killed surface-associated bacteria and prevented biofilm formation under conditions of low bacterial load, whereas under...

  8. Inhibition of melanogenesis by Xanthium strumarium L.

    Science.gov (United States)

    Li, Hailan; Min, Young Sil; Park, Kyoung-Chan; Kim, Dong-Seok

    2012-01-01

    Xanthium strumarium L. (Asteraceae) is traditionally used in Korea to treat skin diseases. In this study, we investigated the effects of a X. strumarium stem extract on melanin synthesis. It inhibited melanin synthesis in a concentration-dependent manner, but it did not directly inhibit tyrosinase, the rate-limiting melanogenic enzyme, and instead downregulated microphthalmia-associated transcription factor (MITF) and tyrosinase expression. MITF, the master regulator of pigmentation, is a target of the Wnt signaling pathway, which includes glycogen synthase kinase 3β (GSK3β) and β-catenin. Hence, the influence of X. strumarium stem extract on GSK3β and β-catenin was further investigated. X. strumarium induced GSK3β phosphorylation (inactivation), but the level of β-catenin did not change. Moreover, a specific GSK3β inhibitor restored X. strumarium-induced melanin reduction. Hence, we suggest that X. strumarium inhibits melanin synthesis through downregulation of tyrosinase via GSK3β phosphorylation.

  9. Mapuche Herbal Medicine Inhibits Blood Platelet Aggregation

    Directory of Open Access Journals (Sweden)

    Susan Skanderup Falkenberg

    2012-01-01

    Full Text Available 12 plant species traditionally used by the Mapuche people in Chile to treat wounds and inflammations have been evaluated for their direct blood platelet inhibition. Seven of the 12 tested plant species showed platelet inhibitory effect in sheep blood, and four of these were also able to inhibit the ADP- (5.0 μM and collagen- (2.0 μg/mL induced aggregations in human blood. These four species in respective extracts (in brackets were Blechnum chilense (MeOH, Luma apiculata (H2O, Amomyrtus luma (DCM : MeOH 1 : 1 and Cestrum parqui (DCM : MeOH 1 : 1. The platelet aggregating inhibitory effects of A. luma (DCM : MeOH 1 : 1, and L. apiculata (H2O were substantial and confirmed by inhibition of platelet surface activation markers.

  10. Distractor inhibition: Evidence from lateralized readiness potentials.

    Science.gov (United States)

    Pramme, Lisa; Dierolf, Angelika M; Naumann, Ewald; Frings, Christian

    2015-08-01

    The present study investigated distractor inhibition on the level of stimulus representation. In a sequential distractor-to-distractor priming task participants had to respond to target letters flanked by distractor digits. Reaction time and stimulus-locked lateralized readiness potentials (S-LRPs) of probe responses were measured. Distractor-target onset asynchrony was varied. For RTs responses to probe targets were faster in the case of prime-distractor repetition compared to distractor changes indicating distractor inhibition. Benefits in RTs and the latency of S-LRP onsets for distractor repetition were also modulated by distractor-target onset asynchrony. For S-LRPs distractor inhibition was only present with a simultaneous onset of distractors and target. The results confirm previous results indicating inhibitory mechanisms of object-based selective attention on the level of distractor representations. Copyright © 2015 Elsevier Inc. All rights reserved.

  11. Terbinafine inhibits gap junctional intercellular communication.

    Science.gov (United States)

    Lee, Ju Yeun; Yoon, Sei Mee; Choi, Eun Ju; Lee, Jinu

    2016-09-15

    Terbinafine is an antifungal agent that selectively inhibits fungal sterol synthesis by blocking squalene epoxidase. We evaluated the effect of terbinafine on gap junctional intercellular communication (GJIC). Fluorescence recovery after photobleaching (FRAP) and I-YFP GJIC assays revealed that terbinafine inhibits GJIC in a reversible and dose-dependent manner in FRT-Cx43 and LN215 cells. Treatment with terbinafine did not affect Cx43 phosphorylation status or intracellular Ca(2+) concentration, well-known action mechanisms of various GJIC blockers. While a structurally related chemical, naftifine, attenuated GJIC, epigallocatechin gallate, another potent squalene epoxidase inhibitor with a different structure, did not. These results suggest that terbinafine inhibits GJIC with a so far unknown mechanism of action. Copyright © 2016 Elsevier Inc. All rights reserved.

  12. Inhibition of aluminum corrosion using Opuntia extract

    International Nuclear Information System (INIS)

    El-Etre, A.Y.

    2003-01-01

    The inhibitive action of the mucilage extracted from the modified stems of prickly pears, toward acid corrosion of aluminum, is tested using weight loss, thermometry, hydrogen evolution and polarization techniques. It was found that the extract acts as a good corrosion inhibitor for aluminum corrosion in 2.0 M HCl solution. The inhibition action of the extract was discussed in view of Langmuir adsorption isotherm. It was found that the adsorption of the extract on aluminum surface is a spontaneous process. The inhibition efficiency (IE) increases as the extract concentration is increased. The effect of temperature on the IE was studied. It was found that the presence of extract increases the activation energy of the corrosion reaction. Moreover, the thermodynamic parameters of the adsorption process were calculated. It was found also that the Opuntia extract provides a good protection to aluminum against pitting corrosion in chloride ion containing solutions

  13. Mapuche herbal medicine inhibits blood platelet aggregation.

    Science.gov (United States)

    Falkenberg, Susan Skanderup; Tarnow, Inge; Guzman, Alfonso; Mølgaard, Per; Simonsen, Henrik Toft

    2012-01-01

    12 plant species traditionally used by the Mapuche people in Chile to treat wounds and inflammations have been evaluated for their direct blood platelet inhibition. Seven of the 12 tested plant species showed platelet inhibitory effect in sheep blood, and four of these were also able to inhibit the ADP- (5.0 μM) and collagen- (2.0 μg/mL) induced aggregations in human blood. These four species in respective extracts (in brackets) were Blechnum chilense (MeOH), Luma apiculata (H(2)O), Amomyrtus luma (DCM : MeOH 1 : 1) and Cestrum parqui (DCM : MeOH 1 : 1). The platelet aggregating inhibitory effects of A. luma (DCM : MeOH 1 : 1), and L. apiculata (H(2)O) were substantial and confirmed by inhibition of platelet surface activation markers.

  14. Members of the heat-shock protein 70 family promote cancer cell growth by distinct mechanisms

    DEFF Research Database (Denmark)

    Rohde, Mikkel; Daugaard, Mads; Jensen, Mette Hartvig

    2005-01-01

    Whereas the stress-inducible heat-shock protein 70 (Hsp70) has gained plenty of attention as a putative target for tumor therapy, little is known about the role of other Hsp70 proteins in cancer. Here we present the first thorough analysis of the expression and function of the cytosolic Hsp70...... proteins in human cancer cells and identify Hsp70-2, a protein essential for spermatogenesis, as an important regulator of cancer cell growth. Targeted knock-down of the individual family members by RNA interference revealed that both Hsp70 and Hsp70-2 were required for cancer cell growth, whereas...

  15. Inhibition of intestinal disaccharidase activity by pentoses

    DEFF Research Database (Denmark)

    Halschou-Jensen, Kia

    on carbohydrate- ingesting enzymes activity in vitro and possible effects on human postprandial blood response. In paper 1 the effects of sugar beet polyphenols from molasses and the potential inhibition of sucrase activity in vitro, was investigated. Two different polyphenol-rich fractions from chromatographic...... separation of molasses from sugar beets and pure ferulic acid were tested. We found no effects of the two fractions of molasses. The pure ferulic acid indicated an inhibition of sucrase in vitr. Both in vitro and in vivo studies have investigated the effects of L-arabinose and D-xylose on carbohydrate...

  16. Sprout inhibition in roots, tubers and bulbs

    International Nuclear Information System (INIS)

    Luna C, P.C.

    1992-05-01

    The treatment with ionizing radiations to low dose impedes that appear sprouts in the tubers (potatoes); bulbs (onion and garlic) and in roots like the ginger and the yucca. The purpose is to inhibit the germination during the process of manipulation and storage, and this way to avoid the lost ones post crop of these products. The radiation dose required to inhibit the germination goes to depend of: the development conditions, the differences of variety, of the storage state of the bulbs and the conditions of cured and storage. (Author)

  17. Mapuche Herbal Medicine Inhibits Blood Platelet Aggregation

    OpenAIRE

    Falkenberg, Susan Skanderup; Tarnow, Inge; Guzman, Alfonso; Mølgaard, Per; Simonsen, Henrik Toft

    2012-01-01

    12 plant species traditionally used by the Mapuche people in Chile to treat wounds and inflammations have been evaluated for their direct blood platelet inhibition. Seven of the 12 tested plant species showed platelet inhibitory effect in sheep blood, and four of these were also able to inhibit the ADP- (5.0??M) and collagen- (2.0??g/mL) induced aggregations in human blood. These four species in respective extracts (in brackets) were Blechnum chilense (MeOH), Luma apiculata (H2O), Amomyrtus l...

  18. Peptide inhibition of human cytomegalovirus infection

    Directory of Open Access Journals (Sweden)

    Morris Cindy A

    2011-02-01

    Full Text Available Abstract Background Human cytomegalovirus (HCMV is the most prevalent congenital viral infection in the United States and Europe causing significant morbidity and mortality to both mother and child. HCMV is also an opportunistic pathogen in immunocompromised individuals, including human immunodeficiency virus (HIV- infected patients with AIDS, and solid organ and allogeneic stem cell transplantation recipients. Current treatments for HCMV-associated diseases are insufficient due to the emergence of drug-induced resistance and cytotoxicity, necessitating novel approaches to limit HCMV infection. The aim of this study was to develop therapeutic peptides targeting glycoprotein B (gB, a major glycoprotein of HCMV that is highly conserved across the Herpesviridae family, that specifically inhibit fusion of the viral envelope with the host cell membrane preventing HCMV entry and infection. Results Using the Wimley-White Interfacial Hydrophobicity Scale (WWIHS, several regions within gB were identified that display a high potential to interact with lipid bilayers of cell membranes and hydrophobic surfaces within proteins. The ability of synthetic peptides analogous to WWIHS-positive sequences of HCMV gB to inhibit viral infectivity was evaluated. Human foreskin fibroblasts (HFF were infected with the Towne-GFP strain of HCMV (0.5 MOI, preincubated with peptides at a range of concentrations (78 nm to 100 μM, and GFP-positive cells were visualized 48 hours post-infection by fluorescence microscopy and analyzed quantitatively by flow cytometry. Peptides that inhibited HCMV infection demonstrated different inhibitory concentration curves indicating that each peptide possesses distinct biophysical properties. Peptide 174-200 showed 80% inhibition of viral infection at a concentration of 100 μM, and 51% and 62% inhibition at concentrations of 5 μM and 2.5 μM, respectively. Peptide 233-263 inhibited infection by 97% and 92% at concentrations of 100

  19. Inhibition of barley grain germination by light

    NARCIS (Netherlands)

    Roth-Bejerano, N.; Meulen, R.M. van der; Wang, M.

    1996-01-01

    Intact grains of barley (Hordeum distichum cv. Triumph) germinated rapidly in the dark or when exposed to brief daily light breaks in the temperature range 15-25°C, although germination proceeded less rapidly at low temperatures. Prolonged illumination (16 h/day) or continuous light inhibited

  20. Probenazole treatment inhibits anthocyanins biosynthesis via ...

    African Journals Online (AJOL)

    It has been found that anthocyanins were accumulated in Arabidopsis under drought or salt stress. In this study, such accumulation was found to be inhibited by external applied probenazole (3-allyloxy-1, 2-benzisothiazole-1,1-dioxide, PBZ), which is the active ingredient in oryzemate used for the protection of rice from ...

  1. Salinomycin, a polyether ionophoric antibiotic, inhibits adipogenesis

    International Nuclear Information System (INIS)

    Szkudlarek-Mikho, Maria; Saunders, Rudel A.; Yap, Sook Fan; Ngeow, Yun Fong; Chin, Khew-Voon

    2012-01-01

    Highlights: ► Salinomycin inhibits preadipocyte differentiation into adipocytes. ► Salinomycin inhibits transcriptional regulation of adipogenesis. ► Pharmacological effects of salinomycin suggest toxicity in cancer therapy. -- Abstract: The polyether ionophoric antibiotics including monensin, salinomycin, and narasin, are widely used in veterinary medicine and as food additives and growth promoters in animal husbandry including poultry farming. Their effects on human health, however, are not fully understood. Recent studies showed that salinomycin is a cancer stem cell inhibitor. Since poultry consumption has risen sharply in the last three decades, we asked whether the consumption of meat tainted with growth promoting antibiotics might have effects on adipose cells. We showed in this report that the ionophoric antibiotics inhibit the differentiation of preadipocytes into adipocytes. The block of differentiation is not due to the induction of apoptosis nor the inhibition of cell proliferation. In addition, salinomycin also suppresses the transcriptional activity of the CCAAT/enhancer binding proteins and the peroxisome proliferator-activated receptor γ. These results suggest that the ionophoric antibiotics can be exploited as novel anti-obesity therapeutics and as pharmacological probes for the study of adipose biology. Further, the pharmacological effects of salinomycin could be a harbinger of its toxicity on the adipose tissue and other susceptible target cells in cancer therapy.

  2. Illustrating Enzyme Inhibition Using Gibbs Energy Profiles

    Science.gov (United States)

    Bearne, Stephen L.

    2012-01-01

    Gibbs energy profiles have great utility as teaching and learning tools because they present students with a visual representation of the energy changes that occur during enzyme catalysis. Unfortunately, most textbooks divorce discussions of traditional kinetic topics, such as enzyme inhibition, from discussions of these same topics in terms of…

  3. Microbial Metabolism and Inhibition Studies of Phenobarbital

    African Journals Online (AJOL)

    Erah

    techniques, high performance liquid chromatography (HPLC), mass spectrometry (MS) ... Keywords: Microbial metabolism, Phenobarbital, Inhibition studies, Rhizopus stolonifer, CYP 2C9, .... 24 h of incubation 0.5 ml of drug solution was ... mode, positive: spray voltage, 3.5 KV: ... Rhizopus stolonifer showed an extra peak at.

  4. Luteoloside Inhibits Proliferation of Human Chronic Myeloid ...

    African Journals Online (AJOL)

    Purpose: To investigate the effects of luteoloside on the proliferation of human chronic ..... Zhang N, Wang D, Zhu Y, Wang J, Lin H. Inhibition ... Han X. Protection of Luteolin-7-O-Glucoside Against ... Hwang YJ, Lee EJ, Kim HR, Hwang KA.

  5. Nickel Inhibits Mitochondrial Fatty Acid Oxidation

    Science.gov (United States)

    Uppala, Radha; McKinney, Richard W.; Brant, Kelly A.; Fabisiak, James P.; Goetzman, Eric S.

    2015-01-01

    Nickel exposure is associated with changes in cellular energy metabolism which may contribute to its carcinogenic properties. Here, we demonstrate that nickel strongly represses mitochondrial fatty acid oxidation—the pathway by which fatty acids are catabolized for energy—in both primary human lung fibroblasts and mouse embryonic fibroblasts. At the concentrations used, nickel suppresses fatty acid oxidation without globally suppressing mitochondrial function as evidenced by increased glucose oxidation to CO2. Pre-treatment with L-carnitine, previously shown to prevent nickel-induced mitochondrial dysfunction in neuroblastoma cells, did not prevent the inhibition of fatty acid oxidation. The effect of nickel on fatty acid oxidation occurred only with prolonged exposure (>5 hr), suggesting that direct inhibition of the active sites of metabolic enzymes is not the mechanism of action. Nickel is a known hypoxia-mimetic that activates hypoxia inducible factor-1α (HIF1α). Nickel-induced inhibition of fatty acid oxidation was blunted in HIF1α knockout fibroblasts, implicating HIF1α as one contributor to the mechanism. Additionally, nickel down-regulated the protein levels of the key fatty acid oxidation enzyme very long-chain acyl-CoA dehydrogenase (VLCAD) in a dose-dependent fashion. In conclusion, inhibition of fatty acid oxidation by nickel, concurrent with increased glucose metabolism, represents a form of metabolic reprogramming that may contribute to nickel-induced carcinogenesis. PMID:26051273

  6. Inhibiting Intuitive Thinking in Mathematics Education

    Science.gov (United States)

    Thomas, Michael O. J.

    2015-01-01

    The papers in this issue describe recent collaborative research into the role of inhibition of intuitive thinking in mathematics education. This commentary reflects on this research from a mathematics education perspective and draws attention to some of the challenges that arise in collaboration between research fields with different cultures,…

  7. Salinomycin, a polyether ionophoric antibiotic, inhibits adipogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Szkudlarek-Mikho, Maria; Saunders, Rudel A. [Department of Medicine, Biochemistry and Cancer Biology, Center for Diabetes and Endocrine Research, College of Medicine, University of Toledo, Toledo, OH 43614 (United States); Yap, Sook Fan [Faculty of Medicine and Health Sciences, Department of Pre-Clinical Sciences, University of Tunku Abdul Rahman (Malaysia); Ngeow, Yun Fong [Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603 (Malaysia); Chin, Khew-Voon, E-mail: khew-voon.chin@utoledo.edu [Department of Medicine, Biochemistry and Cancer Biology, Center for Diabetes and Endocrine Research, College of Medicine, University of Toledo, Toledo, OH 43614 (United States)

    2012-11-30

    Highlights: Black-Right-Pointing-Pointer Salinomycin inhibits preadipocyte differentiation into adipocytes. Black-Right-Pointing-Pointer Salinomycin inhibits transcriptional regulation of adipogenesis. Black-Right-Pointing-Pointer Pharmacological effects of salinomycin suggest toxicity in cancer therapy. -- Abstract: The polyether ionophoric antibiotics including monensin, salinomycin, and narasin, are widely used in veterinary medicine and as food additives and growth promoters in animal husbandry including poultry farming. Their effects on human health, however, are not fully understood. Recent studies showed that salinomycin is a cancer stem cell inhibitor. Since poultry consumption has risen sharply in the last three decades, we asked whether the consumption of meat tainted with growth promoting antibiotics might have effects on adipose cells. We showed in this report that the ionophoric antibiotics inhibit the differentiation of preadipocytes into adipocytes. The block of differentiation is not due to the induction of apoptosis nor the inhibition of cell proliferation. In addition, salinomycin also suppresses the transcriptional activity of the CCAAT/enhancer binding proteins and the peroxisome proliferator-activated receptor {gamma}. These results suggest that the ionophoric antibiotics can be exploited as novel anti-obesity therapeutics and as pharmacological probes for the study of adipose biology. Further, the pharmacological effects of salinomycin could be a harbinger of its toxicity on the adipose tissue and other susceptible target cells in cancer therapy.

  8. Undecylenic Acid Inhibits Morphogenesis of Candida albicans

    OpenAIRE

    McLain, Nealoo; Ascanio, Rhoda; Baker, Carol; Strohaver, Robert A.; Dolan, Joseph W.

    2000-01-01

    Resilient liners are frequently used to treat denture stomatitis, a condition often associated with Candida albicans infections. Of 10 liners tested, 2 were found to inhibit the switch from the yeast form to hyphae and a third was found to stimulate this switch. The inhibitor was determined to be undecylenic acid.

  9. Undecylenic acid inhibits morphogenesis of Candida albicans.

    Science.gov (United States)

    McLain, N; Ascanio, R; Baker, C; Strohaver, R A; Dolan, J W

    2000-10-01

    Resilient liners are frequently used to treat denture stomatitis, a condition often associated with Candida albicans infections. Of 10 liners tested, 2 were found to inhibit the switch from the yeast form to hyphae and a third was found to stimulate this switch. The inhibitor was determined to be undecylenic acid.

  10. Cellulase Inhibition by High Concentrations of Monosaccharides

    DEFF Research Database (Denmark)

    Hsieh, Chia-Wen; Cannella, David; Jørgensen, Henning

    2014-01-01

    Biological degradation of biomass on an industrial scale culminates in high concentrations of end products. It is known that the accumulation of glucose and cellobiose, end products of hydrolysis, inhibit cellulases and decrease glucose yields. Aside from these end products, however, other monosa...

  11. Inhibiting Translation One Protein at a Time.

    Science.gov (United States)

    Disney, Matthew D

    2017-06-01

    Historically, translational inhibitors have been confined to anti-bacterials that globally affect translation. Lintner et al. demonstrate that small molecules can specifically inhibit translation of a single disease-associated protein by stalling the ribosome's nascent chain [1], opening up a new therapeutic strategy for 'undruggable' proteins. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Polysulfonate suramin inhibits Zika virus infection.

    Science.gov (United States)

    Tan, Chee Wah; Sam, I-Ching; Chong, Wei Lim; Lee, Vannajan Sanghiran; Chan, Yoke Fun

    2017-07-01

    Zika virus (ZIKV) is an arthropod-borne flavivirus that causes newborn microcephaly and Guillian-Barré syndrome in adults. No therapeutics are available to treat ZIKV infection or other flaviviruses. In this study, we explored the inhibitory effect of glycosaminoglycans and analogues against ZIKV infection. Highly sulfated heparin, dextran sulfate and suramin significantly inhibited ZIKV infection in Vero cells. De-sulfated heparin analogues lose inhibitory effect, implying that sulfonate groups are critical for viral inhibition. Suramin, an FDA-approved anti-parasitic drug, inhibits ZIKV infection with 3-5 log 10  PFU viral reduction with IC 50 value of ∼2.5-5 μg/ml (1.93 μM-3.85 μM). A time-of-drug-addition study revealed that suramin remains potent even when administrated at 1-24 hpi. Suramin inhibits ZIKV infection by preventing viral adsorption, entry and replication. Molecular dynamics simulation revealed stronger interaction of suramin with ZIKV NS3 helicase than with the envelope protein. Suramin warrants further investigation as a potential antiviral candidate for ZIKV infection. Heparan sulfate (HS) is a cellular attachment receptor for multiple flaviviruses. However, no direct ZIKV-heparin interaction was observed in heparin-binding analysis, and downregulate or removal of cellular HS with sodium chlorate or heparinase I/III did not inhibit ZIKV infection. This indicates that cell surface HS is not utilized by ZIKV as an attachment receptor. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Neural Synchrony during Response Production and Inhibition

    Science.gov (United States)

    Müller, Viktor; Anokhin, Andrey P.

    2012-01-01

    Inhibition of irrelevant information (conflict monitoring) and/or of prepotent actions is an essential component of adaptive self-organized behavior. Neural dynamics underlying these functions has been studied in humans using event-related brain potentials (ERPs) elicited in Go/NoGo tasks that require a speeded motor response to the Go stimuli and withholding a prepotent response when a NoGo stimulus is presented. However, averaged ERP waveforms provide only limited information about the neuronal mechanisms underlying stimulus processing, motor preparation, and response production or inhibition. In this study, we examine the cortical representation of conflict monitoring and response inhibition using time-frequency analysis of electroencephalographic (EEG) recordings during continuous performance Go/NoGo task in 50 young adult females. We hypothesized that response inhibition would be associated with a transient boost in both temporal and spatial synchronization of prefrontal cortical activity, consistent with the role of the anterior cingulate and lateral prefrontal cortices in cognitive control. Overall, phase synchronization across trials measured by Phase Locking Index and phase synchronization between electrode sites measured by Phase Coherence were the highest in the Go and NoGo conditions, intermediate in the Warning condition, and the lowest under Neutral condition. The NoGo condition was characterized by significantly higher fronto-central synchronization in the 300–600 ms window, whereas in the Go condition, delta- and theta-band synchronization was higher in centro-parietal regions in the first 300 ms after the stimulus onset. The present findings suggest that response production and inhibition is supported by dynamic functional networks characterized by distinct patterns of temporal and spatial synchronization of brain oscillations. PMID:22745691

  14. WEE1 inhibition sensitizes osteosarcoma to radiotherapy

    International Nuclear Information System (INIS)

    PosthumaDeBoer, Jantine; Würdinger, Thomas; Graat, Harm CA; Beusechem, Victor W van; Helder, Marco N; Royen, Barend J van; Kaspers, Gertjan JL

    2011-01-01

    The use of radiotherapy in osteosarcoma (OS) is controversial due to its radioresistance. OS patients currently treated with radiotherapy generally are inoperable, have painful skeletal metastases, refuse surgery or have undergone an intralesional resection of the primary tumor. After irradiation-induced DNA damage, OS cells sustain a prolonged G 2 cell cycle checkpoint arrest allowing DNA repair and evasion of cell death. Inhibition of WEE1 kinase leads to abrogation of the G 2 arrest and could sensitize OS cells to irradiation induced cell death. WEE1 expression in OS was investigated by gene-expression data analysis and immunohistochemistry of tumor samples. WEE1 expression in OS cell lines and human osteoblasts was investigated by Western blot. The effect of WEE1 inhibition on the radiosensitivity of OS cells was assessed by cell viability and caspase activation analyses after combination treatment. The presence of DNA damage was visualized using immunofluorescence microscopy. Cell cycle effects were investigated by flow cytometry and WEE1 kinase regulation was analyzed by Western blot. WEE1 expression is found in the majority of tested OS tissue samples. Small molecule drug PD0166285 inhibits WEE1 kinase activity. In the presence of WEE1-inhibitor, irradiated cells fail to repair their damaged DNA, and show higher levels of caspase activation. The inhibition of WEE1 effectively abrogates the irradiation-induced G 2 arrest in OS cells, forcing the cells into premature, catastrophic mitosis, thus enhancing cell death after irradiation treatment. We show that PD0166285, a small molecule WEE1 kinase inhibitor, can abrogate the G 2 checkpoint in OS cells, pushing them into mitotic catastrophe and thus sensitizing OS cells to irradiation-induced cell death. This suggests that WEE1 inhibition may be a promising strategy to enhance the radiotherapy effect in patients with OS

  15. Neural synchrony during response production and inhibition.

    Directory of Open Access Journals (Sweden)

    Viktor Müller

    Full Text Available Inhibition of irrelevant information (conflict monitoring and/or of prepotent actions is an essential component of adaptive self-organized behavior. Neural dynamics underlying these functions has been studied in humans using event-related brain potentials (ERPs elicited in Go/NoGo tasks that require a speeded motor response to the Go stimuli and withholding a prepotent response when a NoGo stimulus is presented. However, averaged ERP waveforms provide only limited information about the neuronal mechanisms underlying stimulus processing, motor preparation, and response production or inhibition. In this study, we examine the cortical representation of conflict monitoring and response inhibition using time-frequency analysis of electroencephalographic (EEG recordings during continuous performance Go/NoGo task in 50 young adult females. We hypothesized that response inhibition would be associated with a transient boost in both temporal and spatial synchronization of prefrontal cortical activity, consistent with the role of the anterior cingulate and lateral prefrontal cortices in cognitive control. Overall, phase synchronization across trials measured by Phase Locking Index and phase synchronization between electrode sites measured by Phase Coherence were the highest in the Go and NoGo conditions, intermediate in the Warning condition, and the lowest under Neutral condition. The NoGo condition was characterized by significantly higher fronto-central synchronization in the 300-600 ms window, whereas in the Go condition, delta- and theta-band synchronization was higher in centro-parietal regions in the first 300 ms after the stimulus onset. The present findings suggest that response production and inhibition is supported by dynamic functional networks characterized by distinct patterns of temporal and spatial synchronization of brain oscillations.

  16. Contrasting neural effects of aging on proactive and reactive response inhibition

    NARCIS (Netherlands)

    Bloemendaal, Mirjam; Zandbelt, Bram; Wegman, Joost; Rest, van de O.; Cools, Roshan; Aarts, Esther

    2016-01-01

    Two distinct forms of response inhibition may underlie observed deficits in response inhibition in aging. We assessed whether age-related neurocognitive impairments in response inhibition reflect deficient reactive inhibition (outright stopping) or also deficient proactive inhibition

  17. Mecanismos de proteção induzidos pela imunização com TgHSP70 e de controle da inflamação pelo tratamento com STAg na infecção por Toxoplasma gondii

    OpenAIRE

    Barenco, Paulo Victor Czarnewski

    2015-01-01

    Toxoplasma gondii é um parasita intracelular obrigatório que apresenta diversos antígenos capazes de modular a resposta imune. Neste trabalho, visamos estudar dois antígenos imunomoduladores através do pré-tratamento para fase aguda e de imunização para fase crônica da infecção. O primeiro objetivo foi estudar o papel do antígeno solúvel de taquizoítas (STAg) nas células epiteliais para controle da inflamação intestinal durante a infecção aguda por T. gondii. Foi demonstrado que o tratamento ...

  18. Mullerian Inhibiting Substances (MIS) Augments IFN-gamma Mediated Inhibition of Breast Cancer Cell Growth

    National Research Council Canada - National Science Library

    Gupta, Vandana

    2006-01-01

    MIS is a member of the TGF family. The purpose of this study is to test the hypothesis that MIS and IFN-gamma