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Sample records for neuronal apoptosis metallothionein

  1. Neuronal apoptosis, metallothionein expression and proinflammatory responses during cerebral malaria in mice

    DEFF Research Database (Denmark)

    Wiese, Lothar; Kurtzhals, Jørgen A L; Penkowa, Milena

    2006-01-01

    -I + II) are increased during CNS pathology and disorders. As previously shown, MT-I + II are neuroprotective through anti-inflammatory, antioxidant and antiapoptotic functions. We have analyzed neuronal apoptosis and MT-I + II expression in brains of mice with experimental CM. METHODS: C57BL/6j mice...... of neurons in CM by TUNEL, pointing out a possible pathophysiological mechanism leading to persisting brain damage. The possible neuroprotective role of MT-I + II during CM deserves further attention....

  2. Histological changes, apoptosis and metallothionein levels in Triturus carnifex (Amphibia, Urodela) exposed to environmental cadmium concentrations

    Energy Technology Data Exchange (ETDEWEB)

    Capaldo, Anna, E-mail: anna.capaldo@unina.it [Department of Biology, University of Naples Federico II, Naples (Italy); Gay, Flaminia [Department of Chemistry and Biology, University of Salerno, Salerno (Italy); Scudiero, Rosaria; Trinchella, Francesca [Department of Biology, University of Naples Federico II, Naples (Italy); Caputo, Ivana; Lepretti, Marilena; Marabotti, Anna; Esposito, Carla [Department of Chemistry and Biology, University of Salerno, Salerno (Italy); Laforgia, Vincenza [Department of Biology, University of Naples Federico II, Naples (Italy)

    2016-04-15

    Highlights: • Specimens of the newt Triturus carnifex were exposed to environmental Cd doses. • Newts exposed to Cd during 9 months accumulated Cd in their tissues. • Cd induced histological alterations in the skin, liver and kidneys. • Cd induced apoptosis only in the kidneys. • Cd did not increase metallothionein levels in the skin and the liver, nor MTs mRNA. - Abstract: The aim of this study was to verify if the freshwater safety values established from the European Community (1998) and the Italian Ministry of Health (2001) for cadmium (44.5 nM/L in drinking water and 178 nM/L in sewage waters) were safe for amphibians, since at these same concentrations cadmium induced endocrine disruption in the newt Triturus carnifex. Adult male specimens of T. carnifex were exposed daily to cadmium (44.5 nM/L and 178 nM/L as CdCl{sub 2}, nominal concentrations), respectively, during 3- and 9-months; at the same time, control newts were exposed to tap water only. The accumulation of cadmium in the skin, liver and kidney, the levels of metallothioneins in the skin and the liver, the expression of metallothionein mRNA in the liver, as well as the presence of histological alterations and of apoptosis in the target organs were evaluated. The 9-months exposure induced cadmium accumulation in all the tissues examined; moreover, histological changes were observed in all the tissues examined, irrespective of the dose or the time of exposure. Apoptosis was only detected in the kidney, whereas metallothioneins and metallothionein mRNA did not increase. This study demonstrates that the existing chronic water quality criterion established for cadmium induces in the newt T. carnifex cadmium accumulation and histological alterations in the target organs examined. Together with our previous results, showing that, at these same concentrations, cadmium induced endocrine disruption, the present results suggest that the existing chronic water quality criterion for cadmium appears to

  3. Mechanisms of Neuronal Apoptosis In Vivo

    National Research Council Canada - National Science Library

    Martin, Lee J

    2004-01-01

    .... Neuronal cell death in the form of apoptosis or necrosis occurs after exposure to neurotoxins, chemical warfare agents, radiation, viruses, and after seizures, trauma, limb amputation, and hypoxic...

  4. The role of metallothionein II in neuronal differentiation and survival

    DEFF Research Database (Denmark)

    Køhler, Lene B; Berezin, Vladimir; Bock, Elisabeth

    2003-01-01

    -I+II can affect neurons directly. It is likely that MT isoforms could be beneficial also during neurodegenerative disorders. In this study, we have examined if MT-II affects survival and neurite extension of dopaminergic and hippocampal neurons. We show for the first time that MT-II treatment can....... Accordingly, treatment with MT-II may be of therapeutic value in neurodegenerative disorders....

  5. Neuronal migration, apoptosis and bipolar disorder.

    Science.gov (United States)

    Uribe, Ezequiel; Wix, Richard

    2012-01-01

    Bipolar disorder, like the majority of psychiatric disorders, is considered a neurodevelopment disease of neurodevelopment. There is an increased rate of neuronal birth and death during this development period. In the particular case of the processes that determine neuronal death, it is known that those neurons that establish connections have to be removed from the central nervous system. There is a deficit of GABAergic interneurons in the cerebral cortex in bipolar disorder, accompanied by overexpression of proapoptic genes. There is also an alteration in the expression of molecules that mediate in the migration of these neurons and their inclusion in functional synapsis during the foetal stage. The role of these molecules in the neuronal death pathways by apoptosis will be reviewed here in an attempt to establish biological hypotheses of the genesis of bipolar disorder. Copyright © 2011 SEP y SEPB. Published by Elsevier Espana. All rights reserved.

  6. Roles of zinc and metallothionein-3 in oxidative stress-induced lysosomal dysfunction, cell death, and autophagy in neurons and astrocytes.

    Science.gov (United States)

    Lee, Sook-Jeong; Koh, Jae-Young

    2010-10-26

    Zinc dyshomeostasis has been recognized as an important mechanism for cell death in acute brain injury. An increase in the level of free or histochemically reactive zinc in astrocytes and neurons is considered one of the major causes of death of these cells in ischemia and trauma. Although zinc dyshomeostasis can lead to cell death via diverse routes, the major pathway appears to involve oxidative stress.Recently, we found that a rise of zinc in autophagic vacuoles, including autolysosomes, is a prerequisite for lysosomal membrane permeabilization and cell death in cultured brain cells exposed to oxidative stress conditions. The source of zinc in this process is likely redox-sensitive zinc-binding proteins such as metallothioneins, which release zinc under oxidative conditions. Of the metallothioneins, metallothionein-3 is especially enriched in the central nervous system, but its physiologic role in this tissue is not well established. Like other metallothioneins, metallothionein-3 may function as metal detoxicant, but is also known to inhibit neurite outgrowth and, sometimes, promote neuronal death, likely by serving as a source of toxic zinc release. In addition, metallothionein-3 regulates lysosomal functions. In the absence of metallothionein-3, there are changes in lysosome-associated membrane protein-1 and -2, and reductions in certain lysosomal enzymes that result in decreased autophagic flux. This may have dual effects on cell survival. In acute oxidative injury, zinc dyshomeostasis and lysosomal membrane permeabilization are diminished in metallothionein-3 null cells, resulting in less cell death. But over the longer term, diminished lysosomal function may lead to the accumulation of abnormal proteins and cause cytotoxicity.The roles of zinc and metallothionein-3 in autophagy and/or lysosomal function have just begun to be investigated. In light of evidence that autophagy and lysosomes may play significant roles in the pathogenesis of various neurological

  7. Roles of zinc and metallothionein-3 in oxidative stress-induced lysosomal dysfunction, cell death, and autophagy in neurons and astrocytes

    Directory of Open Access Journals (Sweden)

    Lee Sook-Jeong

    2010-10-01

    Full Text Available Abstract Zinc dyshomeostasis has been recognized as an important mechanism for cell death in acute brain injury. An increase in the level of free or histochemically reactive zinc in astrocytes and neurons is considered one of the major causes of death of these cells in ischemia and trauma. Although zinc dyshomeostasis can lead to cell death via diverse routes, the major pathway appears to involve oxidative stress. Recently, we found that a rise of zinc in autophagic vacuoles, including autolysosomes, is a prerequisite for lysosomal membrane permeabilization and cell death in cultured brain cells exposed to oxidative stress conditions. The source of zinc in this process is likely redox-sensitive zinc-binding proteins such as metallothioneins, which release zinc under oxidative conditions. Of the metallothioneins, metallothionein-3 is especially enriched in the central nervous system, but its physiologic role in this tissue is not well established. Like other metallothioneins, metallothionein-3 may function as metal detoxicant, but is also known to inhibit neurite outgrowth and, sometimes, promote neuronal death, likely by serving as a source of toxic zinc release. In addition, metallothionein-3 regulates lysosomal functions. In the absence of metallothionein-3, there are changes in lysosome-associated membrane protein-1 and -2, and reductions in certain lysosomal enzymes that result in decreased autophagic flux. This may have dual effects on cell survival. In acute oxidative injury, zinc dyshomeostasis and lysosomal membrane permeabilization are diminished in metallothionein-3 null cells, resulting in less cell death. But over the longer term, diminished lysosomal function may lead to the accumulation of abnormal proteins and cause cytotoxicity. The roles of zinc and metallothionein-3 in autophagy and/or lysosomal function have just begun to be investigated. In light of evidence that autophagy and lysosomes may play significant roles in the

  8. Mutation at Glu23 eliminates the neuron growth inhibitory activity of human metallothionein-3

    International Nuclear Information System (INIS)

    Ding Zhichun; Teng Xinchen; Cai Bin; Wang Hui; Zheng Qi; Wang Yang; Zhou Guoming; Zhang Mingjie; Wu Houming; Sun Hongzhe; Huang Zhongxian

    2006-01-01

    Human metallothionein-3 (hMT3), first isolated and identified as a neuronal growth inhibitory factor (GIF), is a metalloprotein expressed predominantly in brain. However, untill now, the exact mechanism of the bioactivity of hMT3 is still unknown. In order to study the influence of acid-base catalysis on S-nitrosylation of hMT3, we constructed the E23K mutant of hMT3. During the course of bioassay, we found out unexpectedly that mutation at E23 of hMT3 eliminates the neuronal growth inhibitory activity completely. To the best of our knowledge, it is First report that other residues, besides the TCPCP motif, in the β-domain can alter the bioactivity of hMT3. In order to figure out the causes for the loss of bioactivity of the E23K mutant, the biochemical properties were characterized by UV-vis spectroscopy, CD spectroscopy, pH titration, DTNB reaction, EDTA reaction, and SNOC reaction. All data demonstrated that stability of the metal-thiolate cluster and overall structure of the E23K mutant were not altered too much. However, the reaction of the E23K mutant with SNOC exhibited biphasic kinetics and the mutant protein released zinc ions much faster than hMT3 in the initial step, while hMT3 exhibited single kinetic process. The 2D [ 1 H- 15 N] HSQC was also employed to characterize structural changes during the reaction of hMT3 with varying mounts of nitric oxide. It was shown that the resonance of Glu23 disappeared at a molar ratio of NO to protein of 4. Based on these results, we suggest that mutation at Glu23 may alter the NO metabolism and/or affect zinc homeostasis in brain, thus altering the neuronal growth inhibitory activity

  9. Lithium protects ethanol-induced neuronal apoptosis

    International Nuclear Information System (INIS)

    Zhong Jin; Yang Xianlin; Yao Weiguo; Lee Weihua

    2006-01-01

    Lithium is widely used for the treatment of bipolar disorder. Recent studies have demonstrated its neuroprotective effect. Ethanol is a potent neurotoxin that is particularly harmful to the developing nervous system. In this study, we evaluated lithium's neuroprotection against ethanol-induced apoptosis. Transient exposure of infant mice to ethanol caused apoptotic cell death in brain, which was prevented significantly by administering a low dose of lithium 15 min later. In cultured cerebellar granule neurons, ethanol-induced apoptosis and activation of caspase-3/9, both of which were prevented by lithium. However, lithium's protection is not mediated by its commonly known inhibition of glycogen synthase3β, because neither ethanol nor lithium has significant effects on the phosphorylation of Akt (ser473) or GSK3β (ser9). In addition, the selective GSK-3β inhibitor SB-415286 was unable to prevent ethanol-induced apoptosis. These data suggest lithium may be used as a potential preventive measure for ethanol-induced neurological deficits

  10. A metallothionein mimetic peptide protects neurons against kainic acid-induced excitotoxicity

    DEFF Research Database (Denmark)

    Sonn, Katrin; Pankratova, Stanislava; Korshunova, Irina

    2010-01-01

    Metallothioneins I and II (MTI/II) are metal-binding proteins overexpressed in response to brain injury. Recently, we have designed a peptide, termed EmtinB, which is modeled after the beta-domain of MT-II and mimics the biological effects of MTI/II in vitro. Here, we demonstrate the neuroprotect...

  11. Mature neurons dynamically restrict apoptosis via redundant premitochondrial brakes.

    Science.gov (United States)

    Annis, Ryan P; Swahari, Vijay; Nakamura, Ayumi; Xie, Alison X; Hammond, Scott M; Deshmukh, Mohanish

    2016-12-01

    Apoptotic cell death is critical for the early development of the nervous system, but once the nervous system is established, the apoptotic pathway becomes highly restricted in mature neurons. However, the mechanisms underlying this increased resistance to apoptosis in these mature neurons are not completely understood. We have previously found that members of the miR-29 family of microRNAs (miRNAs) are induced with neuronal maturation and that overexpression of miR-29 was sufficient to restrict apoptosis in neurons. To determine whether endogenous miR-29 alone was responsible for the inhibition of cytochrome c release in mature neurons, we examined the status of the apoptotic pathway in sympathetic neurons deficient for all three miR-29 family members. Unexpectedly, we found that the apoptotic pathway remained largely restricted in miR-29-deficient mature neurons. We therefore probed for additional mechanisms by which mature neurons resist apoptosis. We identify miR-24 as another miRNA that is upregulated in the maturing cerebellum and sympathetic neurons that can act redundantly with miR-29 by targeting a similar repertoire of prodeath BH3-only genes. Overall, our results reveal that mature neurons engage multiple redundant brakes to restrict the apoptotic pathway and ensure their long-term survival. © 2016 Federation of European Biochemical Societies.

  12. Sulforaphane Prevents Neuronal Apoptosis and Memory Impairment in Diabetic Rats

    Directory of Open Access Journals (Sweden)

    Gengyin Wang

    2016-08-01

    Full Text Available Background/Aims: To explore the effects of sulforaphane (SFN on neuronal apoptosis in hippocampus and memory impairment in diabetic rats. Methods: Thirty male rats were randomly divided into normal control, diabetic model and SFN treatment groups (N = 10 in each group. Streptozotocin (STZ was applied to establish diabetic model. Water Morris maze task was applied to test learning and memory. Tunel assaying was used to detect apoptosis in hippocampus. The expressions of Caspase-3 and myeloid cell leukemia 1(MCL-1 were detected by western blotting. Neurotrophic factor levels and AKT/GSK3β pathway were also detected. Results: Compared with normal control, learning and memory were apparently impaired, with up-regulation of Caspase-3 and down-regulation of MCL-1 in diabetic rats. Apoptotic neurons were also found in CA1 region after diabetic modeling. By contrast, SFN treatment prevented the memory impairment, decreased the apoptosis of hippocampal neurons. SFN also attenuated the abnormal expression of Caspase-3 and MCL-1 in diabetic model. Mechanically, SFN treatment reversed diabetic modeling-induced decrease of p-Akt, p-GSK3β, NGF and BDNF expressions. Conclusion: SFN could prevent the memory impairment and apoptosis of hippocampal neurons in diabetic rat. The possible mechanism was related to the regulation of neurotropic factors and Akt/GSK3β pathway.

  13. Neuronal apoptosis in the neonates born to preeclamptic mothers.

    Science.gov (United States)

    Cosar, Hese; Ozer, Erdener; Topel, Hande; Kahramaner, Zelal; Turkoglu, Ebru; Erdemir, Aydin; Sutcuoglu, Sumer; Bagriyanik, Alper; Ozer, Esra Arun

    2013-07-01

    Preeclampsia may result in uteroplacental insufficiency and chronic intrauterine fetal distress. The aim of this study is to address this issue investigating neuronal apoptosis in an experimental model of preeclampsia and to evaluate the neurological outcome of the perinatal asphyxia in the neonates born to preeclamptic mother. Two out of four pregnant Sprague-Dawley rats (preeclamptic group) were given water containing 1.8% NaCl on gestation day 15 and 22 in order to establish the model of preeclampsia whereas other two (non-preeclamptic group) received normal diet. A model of perinatal asphyxia was established on the postnatal 7th day to one preeclamptic and one non-preeclamptic dam. Overall 23 pups born to overall four dams were decapitated to assess neuronal apoptosis by the TUNEL assay. The number of apoptotic neuronal cells was significantly higher in the preeclampsia groups in comparison with the control group (p = 0.006 and p = 0.006, respectively). It was also significantly higher in the asphyctic/non-preeclamptic group than the count in the control group (p = 0.01). There was also significant difference between both asphyctic groups (p = 0.003). We conclude that preeclampsia causes small babies for the gestational age and cerebral hypoplasia. Both preeclampsia and perinatal asphyxia can cause increased neuronal apoptosis in the neonatal brains. However, the prognosis for neurological outcome is much worse when the perinatal asphyxia occurs in newborns born to preeclamptic mothers.

  14. Ketamine-induced apoptosis in cultured rat cortical neurons

    International Nuclear Information System (INIS)

    Takadera, Tsuneo; Ishida, Akira; Ohyashiki, Takao

    2006-01-01

    Recent data suggest that anesthetic drugs cause neurodegeneration during development. Ketamine is frequently used in infants and toddlers for elective surgeries. The purpose of this study is to determine whether glycogen synthase kinase-3 (GSK-3) is involved in ketamine-induced apoptosis. Ketamine increased apoptotic cell death with morphological changes which were characterized by cell shrinkage, nuclear condensation or fragmentation. In addition, insulin growth factor-1 completely blocked the ketamine-induced apoptotic cell death. Ketamine decreased Akt phosphorylation. GSK-3 is known as a downstream target of Akt. The selective inhibitors of GSK-3 prevented the ketamine-induced apoptosis. Moreover, caspase-3 activation was accompanied by the ketamine-induced cell death and inhibited by the GSK-3 inhibitors. These results suggest that activation of GSK-3 is involved in ketamine-induced apoptosis in rat cortical neurons

  15. Metallothionein and a peptide modeled after metallothionein, EmtinB, induce neuronal differentiation and survival through binding to receptors of the low-density lipoprotein receptor family

    DEFF Research Database (Denmark)

    Ambjørn, Malene; Asmussen, Johanne W; Lindstam, Mats

    2007-01-01

    outgrowth and survival. MT-mediated neurite outgrowth was furthermore inhibited by an anti-megalin serum. EmtinB-mediated inhibition of apoptosis occurred without a reduction of caspase-3 activity, but was associated with reduced expression of the pro-apoptotic B-cell leukemia/lymphoma-2 interacting member...

  16. Barley metallothioneins

    DEFF Research Database (Denmark)

    Hegelund, Josefine Nymark; Schiller, Michaela; Kichey, Thomas

    2012-01-01

    Metallothioneins (MTs) are low-molecular-weight, cysteine-rich proteins believed to play a role in cytosolic zinc (Zn) and copper (Cu) homeostasis. However, evidence for the functional properties of MTs has been hampered by methodological problems in the isolation and characterization of the prot......Metallothioneins (MTs) are low-molecular-weight, cysteine-rich proteins believed to play a role in cytosolic zinc (Zn) and copper (Cu) homeostasis. However, evidence for the functional properties of MTs has been hampered by methodological problems in the isolation and characterization...

  17. Redefining the role of metallothionein within the injured brain: extracellular metallothioneins play an important role in the astrocyte-neuron response to injury

    DEFF Research Database (Denmark)

    Chung, Roger S; Penkowa, Milena; Dittmann, Justin

    2008-01-01

    for the first time the transfer of MT from astrocytes to neurons over a specific time course in vitro. Finally, we show that MT is rapidly internalized via the cell bodies of retinal ganglion cells in vivo and is a powerful promoter of axonal regeneration through the inhibitory environment of the completely...

  18. Metallothionein (MT)-III

    DEFF Research Database (Denmark)

    Carrasco, J; Giralt, M; Molinero, A

    1999-01-01

    Metallothionein-III is a low molecular weight, heavy-metal binding protein expressed mainly in the central nervous system. First identified as a growth inhibitory factor (GIF) of rat cortical neurons in vitro, it has subsequently been shown to be a member of the metallothionein (MT) gene family...... injected rats. The specificity of the antibody was also demonstrated in immunocytochemical studies by the elimination of the immunostaining by preincubation of the antibody with brain (but not liver) extracts, and by the results obtained in MT-III null mice. The antibody was used to characterize...... the putative differences between the rat brain MT isoforms, namely MT-I+II and MT-III, in the freeze lesion model of brain damage, and for developing an ELISA for MT-III suitable for brain samples. In the normal rat brain, MT-III was mostly present primarily in astrocytes. However, lectin staining indicated...

  19. Chloroquine inhibits autophagy and deteriorates the mitochondrial dysfunction and apoptosis in hypoxic rat neurons.

    Science.gov (United States)

    Li, Peng; Hao, Lei; Guo, Yan-Yan; Yang, Guang-Lu; Mei, Hua; Li, Xiao-Hua; Zhai, Qiong-Xiang

    2018-06-01

    Mitochondrial dysfunction (MD) and apoptosis in the neurons are associated with neonatal hypoxic-ischemic (HI) encephalopathy (HIE). The present study was to explore the influence of autophagy on the induction of MD and apoptosis in the neurons in a neonatal HIE rats and in hypoxia-treated neurons in vitro. Ten-day-old HI rat pups were sacrificed for brain pathological examination and immunohistochemical analysis. The induction of autophagy, apoptosis and MD were also determined in the neurons under hypoxia, with or without autophagy inhibitor, chloroquine (CQ) treatment. HI treatment caused atrophy and apoptosis of neurons, with a significantly increased levels of apoptosis- and autophagy-associated proteins, such as cleaved caspase 3 and the B subunit of autophagy-related microtubule-associated protein 1 light chain 3 (LC3-B). in vitro experiments demonstrated that the hypoxia induced autophagy in neurons, as was inhibited by CQ. The hypoxia-induced cytochrome c release, cleaved caspase 3 and cleaved caspase 9 were aggravated by CQ. Moreover, there were higher levels of reactive oxygen species, more mitochondrial superoxide and less mitochondrial membrane potential in the CQ-treated neurons under hypoxia than in the neurons singularly under hypoxia. Apoptosis and autophagy were induced in HI neonatal rat neurons, autophagy inhibition deteriorates the hypoxia-induced neuron MD and apoptosis. It implies a neuroprotection of autophagy in the hypoxic-ischemic encephalopathy. Administration of autophagy inducer agents might be promising in HIE treatment. Copyright © 2018. Published by Elsevier Inc.

  20. Endoplasmic reticulum stress-mediated neuronal apoptosis by acrylamide exposure

    Energy Technology Data Exchange (ETDEWEB)

    Komoike, Yuta, E-mail: komoike@research.twmu.ac.jp; Matsuoka, Masato, E-mail: matsuoka@research.twmu.ac.jp

    2016-11-01

    Acrylamide (AA) is a well-known neurotoxic compound in humans and experimental animals. However, intracellular stress signaling pathways responsible for the neurotoxicity of AA are still not clear. In this study, we explored the involvement of the endoplasmic reticulum (ER) stress response in AA-induced neuronal damage in vitro and in vivo. Exposure of SH-SY5Y human neuroblastoma cells to AA increased the levels of phosphorylated form of eukaryotic translation initiation factor 2α (eIF2α) and its downstream effector, activating transcription factor 4 (ATF4), indicating the induction of the unfolded protein response (UPR) by AA exposure. Furthermore, AA exposure increased the mRNA level of c/EBP homologous protein (CHOP), the ER stress-dependent apoptotic factor, and caused the accumulation of reactive oxygen species (ROS) in SH-SY5Y cells. Treatments of SH-SY5Y cells with the chemical chaperone, 4-phenylbutyric acid and the ROS scavenger, N-acetyl-cysteine reduced the AA-induced expression of ATF4 protein and CHOP mRNA, and resulted in the suppression of apoptosis. In addition, AA-induced eIF2α phosphorylation was also suppressed by NAC treatment. In consistent with in vitro study, exposure of zebrafish larvae at 6-day post fertilization to AA induced the expression of chop mRNA and apoptotic cell death in the brain, and also caused the disruption of brain structure. These findings suggest that AA exposure induces apoptotic neuronal cell death through the ER stress and subsequent eIF2α–ATF4–CHOP signaling cascade. The accumulation of ROS by AA exposure appears to be responsible for this ER stress-mediated apoptotic pathway. - Highlights: • Exposure of SH-SY5Y cells to AA activates the eIF2α–ATF4 pathway of the UPR. • Exposure of SH-SY5Y cells to AA induces the CHOP expression and apoptosis. • Exposure of zebrafish to AA induces the chop expression and apoptosis in the brain. • AA possibly induces apoptotic neuronal cell death through the ER

  1. Peptides modeled after the alpha-domain of metallothionein induce neurite outgrowth and promote survival of cerebellar granule neurons

    DEFF Research Database (Denmark)

    Asmussen, Johanne Wirenfeldt; Ambjørn, Malene; Bock, Elisabeth

    2009-01-01

    amino acids, as potent stimulators of neuronal differentiation and survival of primary neurons. In addition, we show that a peptide derived from the N-terminus of the MT beta-domain, EmtinBn, promotes neuronal survival. The neuritogenic and survival promoting effects of EmtinAc, similar to MT and Emtin...

  2. Neuroprotective effects of ganoderma lucidum polysaccharides against oxidative stress-induced neuronal apoptosis

    Science.gov (United States)

    Sun, Xin-zhi; Liao, Ying; Li, Wei; Guo, Li-mei

    2017-01-01

    Ganoderma lucidum polysaccharides have protective effects against apoptosis in neurons exposed to ischemia/reperfusion injury, but the mechanisms are unclear. The goal of this study was to investigate the underlying mechanisms of the effects of ganoderma lucidum polysaccharides against oxidative stress-induced neuronal apoptosis. Hydrogen peroxide (H2O2) was used to induce apoptosis in cultured cerebellar granule cells. In these cells, ganoderma lucidum polysaccharides remarkably suppressed H2O2-induced apoptosis, decreased expression of caspase-3, Bax and Bim and increased that of Bcl-2. These findings suggested that ganoderma lucidum polysaccharides regulate expression of apoptosis-associated proteins, inhibit oxidative stress-induced neuronal apoptosis and, therefore, have significant neuroprotective effects. PMID:28761429

  3. Roles of acid sphingomyelinase activation in neuronal cells apoptosis induced by microwave irradiation

    International Nuclear Information System (INIS)

    Zhang Lei; Xu Shangcheng; Zhang Guangbin; Yu Zhengping

    2009-01-01

    The present study is to examine the effect of microwave on acid sphingomyelinase (ASM) activity and expression, and to explore the role of ASM activation in neuronal cells apoptosis induced by microwave irradiation. Primary cultured hippocampal neurons were irradiated by 30 W/cm 2 microwave for 10 min, and ASM activity assay was used to investigate ASM activity alteration. RT-PCR and western blot were used to detect ASM mRNA and protein expression respectively. Apoptosis was observed by Hoechst 33342 fluorescence staining. ASM specific inhibitor imipramine was applied to inhibit ASM activation. It has been found that apoptosis rate of primary cultured hippocampal neurons increased significantly after microwave irradiation. ASM was activated while ASM mRNA and protein expression were upregulated in neurons after microwave irradiation. Pretreatment with imipramine could reverse neuronal apoptosis induced by microwave irradiation. Results show that microwave irradiation causes increment of ASM activation and expression and ASM activation is involved in microwave induced neuronal apoptosis. (authors)

  4. Metallothionein-1+2 protect the CNS after a focal brain injury

    DEFF Research Database (Denmark)

    Giralt, Mercedes; Penkowa, Milena; Lago, Natalia

    2002-01-01

    We have evaluated the physiological relevance of metallothionein-1+2 (MT-1+2) in the CNS following damage caused by a focal cryolesion onto the cortex. In comparison to normal mice, transgenic mice overexpressing the MT-1 isoform (TgMTI* mice) showed a significant decrease of the number...... dramatically reduced the cryolesion-induced oxidative stress and neuronal apoptosis. Remarkably, these effects were also obtained by the intraperitoneal administration of MT-2 to both normal and MT-1+2 knock-out mice. These results fully support the notion that MT-1+2 are essential in the CNS for coping...

  5. Evaluation of the neuronal apoptotic pathways involved in cytoskeletal disruption-induced apoptosis.

    Science.gov (United States)

    Jordà, Elvira G; Verdaguer, Ester; Jimenez, Andrés; Arriba, S Garcia de; Allgaier, Clemens; Pallàs, Mercè; Camins, Antoni

    2005-08-01

    The cytoskeleton is critical to neuronal functioning and survival. Cytoskeletal alterations are involved in several neurodegenerative diseases such as Alzheimer's and Parkinson's diseases. We studied the possible pathways involved in colchicine-induced apoptosis in cerebellar granule neurons (CGNs). Although colchicine evoked an increase in caspase-3, caspase-6 and caspase-9 activation, selective caspase inhibitors did not attenuate apoptosis. Inhibitors of other cysteine proteases such as PD150606 (a calpain-specific inhibitor), Z-Phe-Ala fluoromethyl ketone (a cathepsins-inhibitors) and N(alpha)-p-tosyl-l-lysine chloromethyl ketone (serine-proteases inhibitor) also had no effect on cell death/apoptosis induced by colchicine. However, BAPTA-AM 10 microM (intracellular calcium chelator) prevented apoptosis mediated by cytoskeletal alteration. These data indicate that calcium modulates colchicine-induced apoptosis in CGNs. PARP-1 inhibitors did not prevent apoptosis mediated by colchicine. Finally, colchicine-induced apoptosis in CGNs was attenuated by kenpaullone, a cdk5 inhibitor. Kenpaullone and indirubin also prevented cdk5/p25 activation mediated by colchicine. These findings indicate that cytoskeletal alteration can compromise cdk5 activation, regulating p25 formation and suggest that cdk5 inhibitors attenuate apoptosis mediated by cytoskeletal alteration. The present data indicate the potential therapeutic value of drugs that prevent the formation of p25 for the treatment of neurodegenerative disorders.

  6. Apoptosis in subicular neurons: A comparison between suicide and Addison's disease

    Science.gov (United States)

    Printha, K.; Hulathduwa, S. R.; Samarasinghe, K.; Suh, Y. H.; De Silva, K. R. D.

    2009-01-01

    Background: Stress and depression shows possible links to neuronal death in hippocampus. Subiculum plays a prominent role in limbic stress integration and direct effect of corticosteroids on subicular neurons needs to be defined to assess its subsequent impact on hippocampal plasticity. Aim: This study was intended to assess apoptosis in subicular neurons of a young depressed suicide victim, where presumably stress induced excess of corticosteroids and a case of young Addison's disease with low level of corticosteroids. Materials and Method: Both bilateral adrenal glands (Addison's) and subiculum (both cases) were initially stained with hematoxylin and eosin; subicular neurons of both cases were examined for the degree of apoptosis using ‘ApopTag Kit’. Apoptotic cell counts were expressed as average number of labeled cells/mm2 and the results were analysed statistically using a non-parametric Mann–Whitney U test. Result: Apoptotic neurons were detected in the subicular region of both suicide and Addison victims, and it is statistically significant in both right and left between the cases (P Addison disease where the number of neuronal cell death between right and left was statistically insignificant (P > 0.05). Conclusion: The present study confirms the vulnerability of the subicular neurons to apoptosis, possibly due to corticosteroids in both ends of spectrum. PMID:20048453

  7. Fluoxetine protects against IL-1β-induced neuronal apoptosis via downregulation of p53.

    Science.gov (United States)

    Shan, Han; Bian, Yaqi; Shu, Zhaoma; Zhang, Linxia; Zhu, Jialei; Ding, Jianhua; Lu, Ming; Xiao, Ming; Hu, Gang

    2016-08-01

    Fluoxetine, a selective serotonin reuptake inhibitor, exerts neuroprotective effects in a variety of neurological diseases including stroke, but the underlying mechanism remains obscure. In the present study, we addressed the molecular events in fluoxetine against ischemia/reperfusion-induced acute neuronal injury and inflammation-induced neuronal apoptosis. We showed that treatment of fluoxetine (40 mg/kg, i.p.) with twice injections at 1 h and 12 h after transient middle cerebral artery occlusion (tMCAO) respectively alleviated neurological deficits and neuronal apoptosis in a mouse ischemic stroke model, accompanied by inhibiting interleukin-1β (IL-1β), Bax and p53 expression and upregulating anti-apoptotic protein Bcl-2 level. We next mimicked neuroinflammation in ischemic stroke with IL-1β in primary cultured cortical neurons and found that pretreatment with fluoxetine (1 μM) prevented IL-1β-induced neuronal apoptosis and upregulation of p53 expression. Furthermore, we demonstrated that p53 overexpression in N2a cell line abolished the anti-apoptotic effect of fluoxetine, indicating that p53 downregulation is required for the protective role of fluoxetine in IL-1β-induced neuronal apoptosis. Fluoxetine downregulating p53 expression could be mimicked by SB203580, a specific inhibitor of p38, but blocked by anisomycin, a p38 activator. Collectively, our findings have revealed that fluoxetine protects against IL-1β-induced neuronal apoptosis via p38-p53 dependent pathway, which give us an insight into the potential of fluoxetine in terms of opening up novel therapeutic avenues for neurological diseases including stroke. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Sugammadex, a Neuromuscular Blockade Reversal Agent, Causes Neuronal Apoptosis in Primary Cultures

    Science.gov (United States)

    Palanca, José M.; Aguirre-Rueda, Diana; Granell, Manuel V.; Aldasoro, Martin; Garcia, Alma; Iradi, Antonio; Obrador, Elena; Mauricio, Maria Dolores; Vila, Jose; Gil-Bisquert, Anna; Valles, Soraya L.

    2013-01-01

    Sugammadex, a γ-cyclodextrin that encapsulates selectively steroidal neuromuscular blocking agents, such as rocuronium or vecuronium, has changed the face of clinical neuromuscular pharmacology. Sugammadex allows a rapid reversal of muscle paralysis. Sugammadex appears to be safe and well tolerated. Its blood-brain barrier penetration is poor (Sugammadex in neurons in primary culture. Here we show that clinically relevant sugammadex concentrations cause apoptotic/necrosis neuron death in primary cultures. Studies on the underlying mechanism revealed that sugammadex-induced activation of mitochondria-dependent apoptosis associates with depletion of neuronal cholesterol levels. Furthermore SUG increase CytC, AIF, Smac/Diablo and CASP-3 protein expression in cells in culture. Potential association of SUG-induced alteration in cholesterol homeostasis with oxidative stress and apoptosis activation occurs. Furthermore, resistance/sensitivity to oxidative stress differs between neuronal cell types. PMID:23983586

  9. Antioxidant enzyme gene delivery to protect from HIV-1 gp120-induced neuronal apoptosis.

    Science.gov (United States)

    Agrawal, L; Louboutin, J-P; Reyes, B A S; Van Bockstaele, E J; Strayer, D S

    2006-12-01

    Human immunodeficiency virus-1 (HIV-1) infection in the central nervous system (CNS) may lead to neuronal loss and progressively deteriorating CNS function: HIV-1 gene products, especially gp120, induce free radical-mediated apoptosis. Reactive oxygen species (ROS), are among the potential mediators of these effects. Neurons readily form ROS after gp120 exposure, and so might be protected from ROS-mediated injury by antioxidant enzymes such as Cu/Zn-superoxide dismutase (SOD1) and/or glutathione peroxidase (GPx1). Both enzymes detoxify oxygen free radicals. As they are highly efficient gene delivery vehicles for neurons, recombinant SV40-derived vectors were used for these studies. Cultured mature neurons derived from NT2 cells and primary fetal neurons were transduced with rSV40 vectors carrying human SOD1 and/or GPx1 cDNAs, then exposed to gp120. Apoptosis was measured by terminal deoxynucleotidyl transferase-mediated nick end labeling (TUNEL) assay. Transduction efficiency of both neuron populations was >95%, as assayed by immunostaining. Transgene expression was also ascertained by Western blotting and direct assays of enzyme activity. Gp120 induced apoptosis in a high percentage of unprotected NT2-N. Transduction with SV(SOD1) and SV(GPx1) before gp120 challenge reduced neuronal apoptosis by >90%. Even greater protection was seen in cells treated with both vectors in sequence. Given singly or in combination, they protect neuronal cells from HIV-1-gp120 induced apoptosis. We tested whether rSV40 s can deliver antioxidant enzymes to the CNS in vivo: intracerebral injection of SV(SOD1) or SV(GPx1) into the caudate putamen of rat brain yielded excellent transgene expression in neurons. In vivo transduction using SV(SOD1) also protected neurons from subsequent gp120-induced apoptosis after injection of both into the caudate putamen of rat brain. Thus, SOD1 and GPx1 can be delivered by SV40 vectors in vitro or in vivo. This approach may merit consideration for

  10. Inhibitory Effect of Lycopene on Amyloid-β-Induced Apoptosis in Neuronal Cells.

    Science.gov (United States)

    Hwang, Sinwoo; Lim, Joo Weon; Kim, Hyeyoung

    2017-08-16

    Alzheimer's disease (AD) is a fatal neurodegenerative disease. Brain amyloid-β deposition is a crucial feature of AD, causing neuronal cell death by inducing oxidative damage. Reactive oxygen species (ROS) activate NF-κB, which induces expression of Nucling. Nucling is a pro-apoptotic factor recruiting the apoptosome complex. Lycopene is an antioxidant protecting from oxidative stress-induced cell damage. We investigated whether lycopene inhibits amyloid-β-stimulated apoptosis through reducing ROS and inhibiting mitochondrial dysfunction and NF-κB-mediated Nucling expression in neuronal SH-SY5Y cells. We prepared cells transfected with siRNA for Nucling or nontargeting control siRNA to determine the role of Nucling in amyloid-β-induced apoptosis. The amyloid-β increased intracellular and mitochondrial ROS levels, apoptotic indices (p53, Bax/Bcl-2 ratio, caspase-3 cleavage), NF-kB activation and Nucling expression, while cell viability, mitochondrial membrane potential, and oxygen consumption rate decreased in SH-SY5Y cells. Lycopene inhibited these amyloid-β-induced alterations. However, amyloid-β did not induce apoptosis, determined by cell viability and apoptotic indices (p53, Bax/Bcl-2 ratio, caspase-3 cleavage), in the cells transfected with siRNA for Nucling. Lycopene inhibited apoptosis by reducing ROS, and by inhibiting mitochondrial dysfunction and NF-κB-target gene Nucling expression in neuronal cells. Lycopene may be beneficial for preventing oxidative stress-mediated neuronal death in patients with neurodegeneration.

  11. Caspase-mediated apoptosis induction in zebrafish cerebellar Purkinje neurons.

    Science.gov (United States)

    Weber, Thomas; Namikawa, Kazuhiko; Winter, Barbara; Müller-Brown, Karina; Kühn, Ralf; Wurst, Wolfgang; Köster, Reinhard W

    2016-11-15

    The zebrafish is a well-established model organism in which to study in vivo mechanisms of cell communication, differentiation and function. Existing cell ablation methods are either invasive or they rely on the cellular expression of prokaryotic enzymes and the use of antibiotic drugs as cell death-inducing compounds. We have recently established a novel inducible genetic cell ablation system based on tamoxifen-inducible Caspase 8 activity, thereby exploiting mechanisms of cell death intrinsic to most cell types. Here, we prove its suitability in vivo by monitoring the ablation of cerebellar Purkinje cells (PCs) in transgenic zebrafish that co-express the inducible caspase and a fluorescent reporter. Incubation of larvae in tamoxifen for 8 h activated endogenous Caspase 3 and cell death, whereas incubation for 16 h led to the near-complete loss of PCs by apoptosis. We observed synchronous cell death autonomous to the PC population and phagocytosing microglia in the cerebellum, reminiscent of developmental apoptosis in the forebrain. Thus, induction of apoptosis through targeted activation of caspase by tamoxifen (ATTAC TM ) further expands the repertoire of genetic tools for conditional interrogation of cellular functions. © 2016. Published by The Company of Biologists Ltd.

  12. Metallothionein in Brain Disorders

    Directory of Open Access Journals (Sweden)

    Daniel Juárez-Rebollar

    2017-01-01

    Full Text Available Metallothioneins are a family of proteins which are able to bind metals intracellularly, so their main function is to regulate the cellular metabolism of essential metals. There are 4 major isoforms of MTs (I–IV, three of which have been localized in the central nervous system. MT-I and MT-II have been localized in the spinal cord and brain, mainly in astrocytes, whereas MT-III has been found mainly in neurons. MT-I and MT-II have been considered polyvalent proteins whose main function is to maintain cellular homeostasis of essential metals such as zinc and copper, but other functions have also been considered: detoxification of heavy metals, regulation of gene expression, processes of inflammation, and protection against free radicals generated by oxidative stress. On the other hand, the MT-III has been related in events of pathogenesis of neurodegenerative diseases such as Parkinson and Alzheimer. Likewise, the participation of MTs in other neurological disorders has also been reported. This review shows recent evidence about the role of MT in the central nervous system and its possible role in neurodegenerative diseases as well as in brain disorders.

  13. The pathways by which mild hypothermia inhibits neuronal apoptosis following ischemia/reperfusion injury

    Directory of Open Access Journals (Sweden)

    Chun Luo

    2015-01-01

    Full Text Available Several studies have demonstrated that mild hypothermia exhibits a neuroprotective role and it can inhibit endothelial cell apoptosis following ischemia/reperfusion injury by decreasing casp-ase-3 expression. It is hypothesized that mild hypothermia exhibits neuroprotective effects on neurons exposed to ischemia/reperfusion condition produced by oxygen-glucose deprivation. Mild hypothermia significantly reduced the number of apoptotic neurons, decreased the expression of pro-apoptotic protein Bax and increased mitochondrial membrane potential, with the peak of anti-apoptotic effect appearing between 6 and 12 hours after the injury. These findings indicate that mild hypothermia inhibits neuronal apoptosis following ischemia/reperfusion injury by protecting the mitochondria and that the effective time window is 6-12 hours after ischemia/reperfusion injury

  14. Calreticulin Binds to Fas Ligand and Inhibits Neuronal Cell Apoptosis Induced by Ischemia-Reperfusion Injury

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    Beilei Chen

    2015-01-01

    Full Text Available Background. Calreticulin (CRT can bind to Fas ligand (FasL and inhibit Fas/FasL-mediated apoptosis of Jurkat T cells. However, its effect on neuronal cell apoptosis has not been investigated. Purpose. We aimed to evaluate the neuroprotective effect of CRT following ischemia-reperfusion injury (IRI. Methods. Mice underwent middle cerebral artery occlusion (MCAO and SH-SY5Y cells subjected to oxygen glucose deprivation (OGD were used as models for IRI. The CRT protein level was detected by Western blotting, and mRNA expression of CRT, caspase-3, and caspase-8 was measured by real-time PCR. Immunofluorescence was used to assess the localization of CRT and FasL. The interaction of CRT with FasL was verified by coimmunoprecipitation. SH-SY5Y cell viability was determined by MTT assay, and cell apoptosis was assessed by flow cytometry. The measurement of caspase-8 and caspase-3 activity was carried out using caspase activity assay kits. Results. After IRI, CRT was upregulated on the neuron surface and bound to FasL, leading to increased viability of OGD-exposed SH-SY5Y cells and decreased activity of caspase-8 and caspase-3. Conclusions. This study for the first time revealed that increased CRT inhibited Fas/FasL-mediated neuronal cell apoptosis during the early stage of ischemic stroke, suggesting it to be a potential protector activated soon after IRI.

  15. MicroRNA-132 protects hippocampal neurons against oxygen-glucose deprivation-induced apoptosis.

    Science.gov (United States)

    Sun, Zu-Zhen; Lv, Zhan-Yun; Tian, Wen-Jing; Yang, Yan

    2017-09-01

    Hypoxic-ischemic brain injury (HIBI) results in death or long-term neurologic impairment in both adults and children. In this study, we investigated the effects of microRNA-132 (miR-132) dysregulation on oxygen-glucose deprivation (OGD)-induced apoptosis in fetal rat hippocampal neurons, in order to reveal the therapeutic potential of miR-132 on HIBI. MiR-132 dysregulation was induced prior to OGD exposure by transfection of primary fetal rat hippocampal neurons with miR-132 mimic or miR-132 inhibitor. The effects of miR-132 overexpression and suppression on OGD-stimulated hippocampal neurons were evaluated by detection of cell viability, apoptotic cells rate, and the expression of apoptosis-related proteins. Besides, TargetScan database and dual luciferase activity assay were used to seek a target gene of miR-132. As a result, miR-132 was highly expressed in hippocampal neurons following 2 h of OGD exposure. MiR-132 overexpression significantly increased OGD-diminished cell viability and reduced OGD-induced apoptosis at 12, 24, and 48 h post-OGD. MiR-132 overexpression significantly down-regulated the expressions of Bax, cytochrome c, and caspase-9, but up-regulated BCl-2. Caspase-3 activity was also significantly decreased by miR-132 overexpression. Furthermore, FOXO3 was a direct target of miR-132, and it was negatively regulated by miR-132. To conclude, our results provide evidence that miR-132 protects hippocampal neurons against OGD injury by inhibiting apoptosis.

  16. Dopamine Attenuates Ketamine-Induced Neuronal Apoptosis in the Developing Rat Retina Independent of Early Synchronized Spontaneous Network Activity.

    Science.gov (United States)

    Dong, Jing; Gao, Lingqi; Han, Junde; Zhang, Junjie; Zheng, Jijian

    2017-07-01

    Deprivation of spontaneous rhythmic electrical activity in early development by anesthesia administration, among other interventions, induces neuronal apoptosis. However, it is unclear whether enhancement of neuronal electrical activity attenuates neuronal apoptosis in either normal development or after anesthesia exposure. The present study investigated the effects of dopamine, an enhancer of spontaneous rhythmic electrical activity, on ketamine-induced neuronal apoptosis in the developing rat retina. TUNEL and immunohistochemical assays indicated that ketamine time- and dose-dependently aggravated physiological and ketamine-induced apoptosis and inhibited early-synchronized spontaneous network activity. Dopamine administration reversed ketamine-induced neuronal apoptosis, but did not reverse the inhibitory effects of ketamine on early synchronized spontaneous network activity despite enhancing it in controls. Blockade of D1, D2, and A2A receptors and inhibition of cAMP/PKA signaling partially antagonized the protective effect of dopamine against ketamine-induced apoptosis. Together, these data indicate that dopamine attenuates ketamine-induced neuronal apoptosis in the developing rat retina by activating the D1, D2, and A2A receptors, and upregulating cAMP/PKA signaling, rather than through modulation of early synchronized spontaneous network activity.

  17. Endoplasmic Reticulum Stress-Mediated Hippocampal Neuron Apoptosis Involved in Diabetic Cognitive Impairment

    Directory of Open Access Journals (Sweden)

    Xiaoming Zhang

    2013-01-01

    Full Text Available Poor management of DM causes cognitive impairment while the mechanism is still unconfirmed. The aim of the present study was to investigate the activation of C/EBP Homology Protein (CHOP, the prominent mediator of the endoplasmic reticulum (ER stress-induced apoptosis under hyperglycemia. We employed streptozotocin- (STZ- induced diabetic rats to explore the ability of learning and memory by the Morris water maze test. The ultrastructure of hippocampus in diabetic rats and cultured neurons in high glucose medium were observed by transmission electron microscopy and scanning electron microscopy. TUNEL staining was also performed to assess apoptotic cells while the expression of CHOP was assayed by immunohistochemistry and Western blot assay in these hippocampal neurons. Six weeks after diabetes induction, the escape latency increased and the average frequency in finding the platform decreased in diabetic rats (P<0.05. The morphology of neuron and synaptic structure was impaired; the number of TUNEL-positive cells and the expression of CHOP in hippocampus of diabetic rats and high glucose medium cultured neurons were markedly altered (P<0.05. The present results suggested that the CHOP-dependent endoplasmic reticulum (ER stress-mediated apoptosis may be involved in hyperglycemia-induced hippocampal synapses and neurons impairment and promote the diabetic cognitive impairment.

  18. O-GlcNAcylation regulates ischemia-induced neuronal apoptosis through AKT signaling.

    Science.gov (United States)

    Shi, Jianhua; Gu, Jin-hua; Dai, Chun-ling; Gu, Jianlan; Jin, Xiaoxia; Sun, Jianming; Iqbal, Khalid; Liu, Fei; Gong, Cheng-Xin

    2015-09-28

    Apoptosis plays an important role in neural development and neurological disorders. In this study, we found that O-GlcNAcylation, a unique protein posttranslational modification with O-linked β-N-acetylglucosamine (GlcNAc), promoted apoptosis through attenuating phosphorylation/activation of AKT and Bad. By using co-immunoprecipitation and mutagenesis techniques, we identified O-GlcNAc modification at both Thr308 and Ser473 of AKT. O-GlcNAcylation-induced apoptosis was attenuated by over-expression of AKT. We also found a dynamic elevation of protein O-GlcNAcylation during the first four hours of cerebral ischemia, followed by continuous decline after middle cerebral artery occlusion (MCAO) in the mouse brain. The elevation of O-GlcNAcylation coincided with activation of cell apoptosis. Finally, we found a negative correlation between AKT phosphorylation and O-GlcNAcylation in ischemic brain tissue. These results indicate that cerebral ischemia induces a rapid increase of O-GlcNAcylation that promotes apoptosis through down-regulation of AKT activity. These findings provide a novel mechanism through which O-GlcNAcylation regulates ischemia-induced neuronal apoptosis through AKT signaling.

  19. Fractalkine is a "find-me" signal released by neurons undergoing ethanol-induced apoptosis.

    Science.gov (United States)

    Sokolowski, Jennifer D; Chabanon-Hicks, Chloe N; Han, Claudia Z; Heffron, Daniel S; Mandell, James W

    2014-01-01

    Apoptotic neurons generated during normal brain development or secondary to pathologic insults are efficiently cleared from the central nervous system. Several soluble factors, including nucleotides, cytokines, and chemokines are released from injured neurons, signaling microglia to find and clear debris. One such chemokine that serves as a neuronal-microglial communication factor is fractalkine, with roles demonstrated in several models of adult neurological disorders. Lacking, however, are studies investigating roles for fractalkine in perinatal brain injury, an important clinical problem with no effective therapies. We used a well-characterized mouse model of ethanol-induced apoptosis to assess the role of fractalkine in neuronal-microglial signaling. Quantification of apoptotic debris in fractalkine-knockout (KO) and CX3CR1-KO mice following ethanol treatment revealed increased apoptotic bodies compared to wild type mice. Ethanol-induced injury led to release of soluble, extracellular fractalkine. The extracellular media harvested from apoptotic brains induces microglial migration in a fractalkine-dependent manner that is prevented by neutralization of fractalkine with a blocking antibody or by deficiency in the receptor, CX3CR1. This suggests fractalkine acts as a "find-me" signal, recruiting microglial processes toward apoptotic cells to promote their clearance. Next, we aimed to determine whether there are downstream alterations in cytokine gene expression due to fractalkine signaling. We examined mRNA expression in fractalkine-KO and CX3CR1-KO mice after alcohol-induced apoptosis and found differences in cytokine production in the brains of these KOs by 6 h after ethanol treatment. Collectively, this suggests that fractalkine acts as a "find me" signal released by apoptotic neurons, and subsequently plays a critical role in modulating both clearance and inflammatory cytokine gene expression after ethanol-induced apoptosis.

  20. Fractalkine is a "find-me" signal released by neurons undergoing ethanol-induced apoptosis

    Directory of Open Access Journals (Sweden)

    Jennifer D Sokolowski

    2014-11-01

    Full Text Available Apoptotic neurons generated during normal brain development or secondary to pathologic insults are efficiently cleared from the central nervous system. Several soluble factors, including nucleotides, cytokines, and chemokines are released from injured neurons, signaling microglia to find and clear debris. One such chemokine that serves as a neuronal-microglial communication factor is fractalkine, with roles demonstrated in several models of adult neurological disorders. Lacking, however, are studies investigating roles for fractalkine in perinatal brain injury, an important clinical problem with no effective therapies. We used a well-characterized mouse model of ethanol-induced apoptosis to assess the role of fractalkine in neuronal-microglial signaling. Quantification of apoptotic debris in fractalkine-knockout and CX3CR1-knockout mice following ethanol treatment revealed increased apoptotic bodies compared to wild type mice. Ethanol-induced injury led to release of soluble, extracellular fractalkine. The extracellular media harvested from apoptotic brains induces microglial migration in a fractalkine-dependent manner that is prevented by neutralization of fractalkine with a blocking antibody or by deficiency in the receptor, CX3CR1. This suggests fractalkine acts as a ‘find-me’ signal, recruiting microglial processes toward apoptotic cells to promote their clearance. Next, we aimed to determine whether there are downstream alterations in cytokine gene expression due to fractalkine signaling. We examined mRNA expression in fractalkine-knockout and CX3CR1-knockout mice after alcohol-induced apoptosis and found differences in cytokine production in the brains of these knockouts by 6 hours after ethanol treatment. Collectively, this suggests that fractalkine acts as a ‘find me’ signal released by apoptotic neurons, and subsequently plays a critical role in modulating both phagocytic clearance and inflammatory cytokine gene expression after

  1. Early Exercise Protects against Cerebral Ischemic Injury through Inhibiting Neuron Apoptosis in Cortex in Rats

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    Junfa Wu

    2013-03-01

    Full Text Available Early exercise is an effective strategy for stroke treatment, but the underlying mechanism remains poorly understood. Apoptosis plays a critical role after stroke. However, it is unclear whether early exercise inhibits apoptosis after stroke. The present study investigated the effect of early exercise on apoptosis induced by ischemia. Adult SD rats were subjected to transient focal cerebral ischemia by middle cerebral artery occlusion model (MCAO and were randomly divided into early exercise group, non-exercise group and sham group. Early exercise group received forced treadmill training initiated at 24 h after operation. Fourteen days later, the cell apoptosis were detected by TdT-mediated dUTP-biotin nick-end labeling (TUNEL and Fluoro-Jade-B staining (F-J-B. Caspase-3, cleaved caspase-3 and Bcl-2 were determined by western blotting. Cerebral infarct volume and motor function were evaluated by cresyl violet staining and foot fault test respectively. The results showed that early exercise decreased the number of apoptotic cells (118.74 ± 6.15 vs. 169.65 ± 8.47, p < 0.05, n = 5, inhibited the expression of caspase-3 and cleaved caspase-3 (p < 0.05, n = 5, and increased the expression of Bcl-2 (p < 0.05, n = 5. These data were consistent with reduced infarct volume and improved motor function. These results suggested that early exercise could provide neuroprotection through inhibiting neuron apoptosis.

  2. Zinc Deficiency Induces Apoptosis via Mitochondrial p53- and Caspase-Dependent Pathways in Human Neuronal Precursor Cells

    Science.gov (United States)

    Seth, Rohit; Corniola, Rikki S.; Gower-Winter, Shannon D.; Morgan, Thomas J., Jr.; Bishop, Brian; Levenson, Cathy W.

    2015-01-01

    Previous studies have shown that zinc deficiency leads to apoptosis of neuronal precursor cells in vivo and in vitro. In addition to the role of p53 as a nuclear transcription factor in zinc deficient cultured human neuronal precursors (NT-2), we have now identified the translocation of phosphorylated p53 to the mitochondria and p53-dependent…

  3. The Fas/Fas ligand death receptor pathway contributes to phenylalanine-induced apoptosis in cortical neurons.

    Directory of Open Access Journals (Sweden)

    Xiaodong Huang

    Full Text Available Phenylketonuria (PKU, an autosomal recessive disorder of amino acid metabolism caused by mutations in the phenylalanine hydroxylase (PAH gene, leads to childhood mental retardation by exposing neurons to cytotoxic levels of phenylalanine (Phe. A recent study showed that the mitochondria-mediated (intrinsic apoptotic pathway is involved in Phe-induced apoptosis in cultured cortical neurons, but it is not known if the death receptor (extrinsic apoptotic pathway and endoplasmic reticulum (ER stress-associated apoptosis also contribute to neurodegeneration in PKU. To answer this question, we used specific inhibitors to block each apoptotic pathway in cortical neurons under neurotoxic levels of Phe. The caspase-8 inhibitor Z-IETD-FMK strongly attenuated apoptosis in Phe-treated neurons (0.9 mM, 18 h, suggesting involvement of the Fas receptor (FasR-mediated cell death receptor pathway in Phe toxicity. In addition, Phe significantly increased cell surface Fas expression and formation of the Fas/FasL complex. Blocking Fas/FasL signaling using an anti-Fas antibody markedly inhibited apoptosis caused by Phe. In contrast, blocking the ER stress-induced cell death pathway with salubrinal had no effect on apoptosis in Phe-treated cortical neurons. These experiments demonstrate that the Fas death receptor pathway contributes to Phe-induced apoptosis and suggest that inhibition of the death receptor pathway may be a novel target for neuroprotection in PKU patients.

  4. Glycogen synthase kinase-3: a key kinase in retinal neuron apoptosis in early diabetic retinopathy

    Institute of Scientific and Technical Information of China (English)

    Li Zhaohui; Ma Ling; Chen Xiaodong; Li Yonghao; Li Shiyi; Zhang Jinglin; Lu Lin

    2014-01-01

    Background Diabetes-related pathogenic factors can cause retinal ganglion cell (RGC) apoptosis,but the specific mechanism is not very clear.The aim of this study is to investigate the correlation between glycogen synthase kinase-3 (GSK-3) activation and retinal neuron apoptosis.Methods In an in vitro experiment,the number of apoptotic RGC-5 cells differentiated by staurosporine was evaluated via flow cytometry and nuclei staining using Hoechst 33258.GSK-3 phosphorylation and caspase-3 activation in RGC-5 cells after serum deprivation were determined using Western blotting.Mitochondrial membrane potential was detected using the dye 5,5',6,6'-tetrachloro-1,1',3,3'-tetrethyl benzimidalyl carbocyanine iodide,and reactive oxygen species (ROS) levels were measured with dihydroethidium.In an in vivo experiment,the number of apoptotic retinal neurons was evaluated via terminal transferase dUTP nick-end labeling (TUNEL),and GSK-3 phosphorylation was determined using Western blotting,in the retinal nerve epithelial tissue of rats in which diabetes was induced by intravenous tail-vein injection of streptozotocin for 4 weeks.Results The levels of phosphorylated Ser21/9 in GSK-3α/β and p-T308/S473-AKT were lower and the cleaved caspase-3 levels were higher in the serum-deprived model (P <0.05).Lithium chloride treatment was associated with a slower rate of apoptosis,increased mitochondrial membrane potential,and decreased ROS levels in differentiated RGC-5 cells (P <0.05).The level of blood glucose and the number of TUNEL-positive cells in the whole-mounted retinas were higher (P <0.01),and the levels of phosphorylated Ser21/9 in GSK-3α/β and body weight were lower (P <0.05).However,the thickness of the retinal nerve epithelial layer was not significantly less in diabetic rats compared with control group.Lithium chloride intravitreal injection increased the levels of phosphorylated Ser21/9 in GSK-3α/β and decreased TUNEL-positive cells in the whole-mounted retinas

  5. Arsenic moiety in gallium arsenide is responsible for neuronal apoptosis and behavioral alterations in rats

    International Nuclear Information System (INIS)

    Flora, Swaran J.S.; Bhatt, Kapil; Mehta, Ashish

    2009-01-01

    Gallium arsenide (GaAs), an intermetallic semiconductor finds widespread applications in high frequency microwave and millimeter wave, and ultra fast supercomputers. Extensive use of GaAs has led to increased exposure to humans working in semiconductor industry. GaAs has the ability to dissociate into its constitutive moieties at physiological pH and might be responsible for the oxidative stress. The present study was aimed at evaluating, the principle moiety (Ga or As) in GaAs to cause neurological dysfunction based on its ability to cause apoptosis, in vivo and in vitro and if this neuronal dysfunction translated to neurobehavioral changes in chronically exposed rats. Result indicated that arsenic moiety in GaAs was mainly responsible for causing oxidative stress via increased reactive oxygen species (ROS) and nitric oxide (NO) generation, both in vitro and in vivo. Increased ROS further caused apoptosis via mitochondrial driven pathway. Effects of oxidative stress were also confirmed based on alterations in antioxidant enzymes, GPx, GST and SOD in rat brain. We noted that ROS induced oxidative stress caused changes in the brain neurotransmitter levels, Acetylcholinesterase and nitric oxide synthase, leading to loss of memory and learning in rats. The study demonstrates for the first time that the slow release of arsenic moiety from GaAs is mainly responsible for oxidative stress induced apoptosis in neuronal cells causing behavioral changes.

  6. CX3CL1-mediated macrophage activation contributed to paclitaxel-induced DRG neuronal apoptosis and painful peripheral neuropathy.

    Science.gov (United States)

    Huang, Zhen-Zhen; Li, Dai; Liu, Cui-Cui; Cui, Yu; Zhu, He-Quan; Zhang, Wen-Wen; Li, Yong-Yong; Xin, Wen-Jun

    2014-08-01

    Painful peripheral neuropathy is a dose-limiting side effect of paclitaxel therapy, which hampers the optimal clinical management of chemotherapy in cancer patients. Currently the underlying mechanisms remain largely unknown. Here we showed that the clinically relevant dose of paclitaxel (3×8mg/kg, cumulative dose 24mg/kg) induced significant upregulation of the chemokine CX3CL1 in the A-fiber primary sensory neurons in vivo and in vitro and infiltration of macrophages into the dorsal root ganglion (DRG) in rats. Paclitaxel treatment also increased cleaved caspase-3 expression, induced the loss of primary afferent terminal fibers and decreased sciatic-evoked A-fiber responses in the spinal dorsal horn, indicating DRG neuronal apoptosis induced by paclitaxel. In addition, the paclitaxel-induced DRG neuronal apoptosis occurred exclusively in the presence of macrophage in vitro study. Intrathecal or systemic injection of CX3CL1 neutralizing antibody blocked paclitaxel-induced macrophage recruitment and neuronal apoptosis in the DRG, and also attenuated paclitaxel-induced allodynia. Furthermore, depletion of macrophage by systemic administration of clodronate inhibited paclitaxel-induced allodynia. Blocking CX3CL1 decreased activation of p38 MAPK in the macrophage, and inhibition of p38 MAPK activity blocked the neuronal apoptosis and development of mechanical allodynia induced by paclitaxel. These findings provide novel evidence that CX3CL1-recruited macrophage contributed to paclitaxel-induced DRG neuronal apoptosis and painful peripheral neuropathy. Copyright © 2014 Elsevier Inc. All rights reserved.

  7. Turmeric extract inhibits apoptosis of hippocampal neurons of trimethyltin-exposed rats.

    Science.gov (United States)

    Yuliani, S; Widyarini, S; Mustofa; Partadiredja, G

    2017-01-01

    The aim of the present study was to reveal the possible antiapoptotic effect of turmeric (Curcuma longa Linn.) on the hippocampal neurons of rats exposed to trimethyltin (TMT). Oxidative damage in the hippocampus can induce the apoptosis of neurons associated with the pathogenesis of dementiaMETHODS. The ethanolic turmeric extract and a citicoline (as positive control) solution were administered to the TMT-exposed rats for 28 days. The body weights of rats were recorded once a week. The hippocampal weights and imumunohistochemical expression of caspase 3 proteins in the CA1 and CA2-CA3 regions of the hippocampi were examined at the end of the experiment. Immunohistochemical analysis showed that the injection of TMT increased the expression of caspase 3 in the CA1 and CA2-CA3 regions of hippocampus. TMT also decreased the body and hippocampal weights. Furthermore, the administration of 200 mg/kg bw dose of turmeric extract decreased the caspase 3 expression in the CA2-CA3 pyramidal neurons but not in the CA1 neurons. It also prevented the decrease of the body and hippocampal weights. We suggest that the 200 mg/kg bw dose of turmeric extract may exert antiapoptotic effect on the hippocampal neurons of the TMT-exposed rats (Tab. 1, Fig. 3, Ref. 49).

  8. Blockade of store-operated calcium entry alleviates high glucose-induced neurotoxicity via inhibiting apoptosis in rat neurons.

    Science.gov (United States)

    Xu, Zhenkuan; Xu, Wenzhe; Song, Yan; Zhang, Bin; Li, Feng; Liu, Yuguang

    2016-07-25

    Altered store-operated calcium entry (SOCE) has been suggested to be involved in many diabetic complications. However, the association of altered SOCE and diabetic neuronal damage remains unclear. This study aimed to investigate the effects of altered SOCE on primary cultured rat neuron injury induced by high glucose. Our data demonstrated that high glucose increased rat neuron injury and upregulated the expression of store-operated calcium channel (SOC). Inhibition of SOCE by a pharmacological inhibitor and siRNA knockdown of stromal interaction molecule 1 weakened the intracellular calcium overload, restored mitochondrial membrane potential, downregulated cytochrome C release and inhibited cell apoptosis. As well, treatment with the calcium chelator BAPTA-AM prevented cell apoptosis by ameliorating the high glucose-increased intracellular calcium level. These findings suggest that SOCE blockade may alleviate high glucose-induced neuronal damage by inhibiting apoptosis. SOCE might be a promising therapeutic target in diabetic neurotoxicity. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  9. Methamphetamine exposure triggers apoptosis and autophagy in neuronal cells by activating the C/EBPβ-related signaling pathway.

    Science.gov (United States)

    Xu, Xiang; Huang, Enping; Luo, Baoying; Cai, Dunpeng; Zhao, Xu; Luo, Qin; Jin, Yili; Chen, Ling; Wang, Qi; Liu, Chao; Lin, Zhoumeng; Xie, Wei-Bing; Wang, Huijun

    2018-06-25

    Methamphetamine (Meth) is a widely abused psychoactive drug that primarily damages the nervous system, notably causing dopaminergic neuronal apoptosis. CCAAT-enhancer binding protein (C/EBPβ) is a transcription factor and an important regulator of cell apoptosis and autophagy. Insulin-like growth factor binding protein (IGFBP5) is a proapoptotic factor that mediates Meth-induced neuronal apoptosis, and Trib3 (tribbles pseudokinase 3) is an endoplasmic reticulum (ER) stress-inducible gene involved in autophagic cell death through the mammalian target of rapamycin (mTOR) signaling pathway. To test the hypothesis that C/EBPβ is involved in Meth-induced IGFBP5-mediated neuronal apoptosis and Trib3-mediated neuronal autophagy, we measured the protein expression of C/EBPβ after Meth exposure and evaluated the effects of silencing C/EBPβ, IGFBP5, or Trib3 on Meth-induced apoptosis and autophagy in neuronal cells and in the rat striatum after intrastriatal Meth injection. We found that, at relatively high doses, Meth exposure increased C/EBPβ protein expression, which was accompanied by increased neuronal apoptosis and autophagy; triggered the IGFBP5-mediated, p53-up-regulated modulator of apoptosis (PUMA)-related mitochondrial apoptotic signaling pathway; and stimulated the Trib3-mediated ER stress signaling pathway through the Akt-mTOR signaling axis. We also found that autophagy is an early response to Meth-induced stress upstream of apoptosis and plays a detrimental role in Meth-induced neuronal cell death. These results suggest that Meth exposure induces C/EBPβ expression, which plays an essential role in the neuronal apoptosis and autophagy induced by relatively high doses of Meth; however, relatively low concentrations of Meth did not change the expression of C/EBPβ in vitro. Further studies are needed to elucidate the role of C/EBPβ in low-dose Meth-induced neurotoxicity.-Xu, X., Huang, E., Luo, B., Cai, D., Zhao, X., Luo, Q., Jin, Y., Chen, L., Wang, Q

  10. Metallothionein as a useful marker in Hodgkin lymphoma subclassification

    DEFF Research Database (Denmark)

    Penkowa, Milena; Sørensen, Brit Ladegaard; Nielsen, Signe Lidou

    2009-01-01

    Metallothionein (MT) expression is considered to be a prognostic factor that promotes tumor resistance to apoptosis. In non-Hodgkin lymphomas, MT is differentially expressed and constitutes a risk factor. We have characterised MT in lymph nodes of Hodgkin lymphoma (HL) [patients with nodular...

  11. Berberine prevents nigrostriatal dopaminergic neuronal loss and suppresses hippocampal apoptosis in mice with Parkinson's disease.

    Science.gov (United States)

    Kim, Mia; Cho, Ki-Ho; Shin, Mal-Soon; Lee, Jae-Min; Cho, Han-Sam; Kim, Chang-Ju; Shin, Dong-Hoon; Yang, Hyeon Jeong

    2014-04-01

    Parkinson's disease (PD) is a progressive neurodegenerative disorder characterized by the selective loss of nigral dopaminergic neurons and a reduction in striatal dopaminergic fibers, which result in tremors, rigidity, bradykinesia and gait disturbance. In addition to motor dysfunction, dementia is a widely recognized symptom of patients with PD. Berberine, an isoquinoline alkaloid isolated from Berberis vulgaris L., is known to exert anxiolytic, analgesic, anti-inflammatory, antipsychotic, antidepressant and anti-amnesic effects. In the present study, we investigated the effects of berberine on short-term memory in relation to dopamine depletion and hippocampal neurogenesis using a mouse model of PD, induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine/probenecid (MPTP/P) treatment. Mice in the berberine-treated groups were orally administered berberine once a day for a total of 5 weeks. Our results revealed that the injection of MPTP/P induced dopaminergic neuronal death in the substantia nigra and fiber loss in the striatum. This resulted in impaired motor balance and coordination, as assessed by the beam walking test. We further demonstrated that MPTP/P-induced apoptosis in the hippocampus deteriorated short-term memory, as shown by the step-down avoidance task. By contrast, neurogenesis in the hippocampal dentate gyrus, which is a compensatory adaptive response to excessive apoptosis, was increased upon PD induction. However, treatment with berberine enhanced motor balance and coordination by preventing dopaminergic neuronal damage. Treatment with berberine also improved short-term memory by inhibiting apoptosis in the hippocampus. Berberine demonstrated maximal potency at 50 mg/kg. Based on these data, treatment with berberine may serve as a potential therapeutic strategy for the alleviation of memory impairment and motor dysfunction in patients with PD.

  12. The effects of piracetam on heroin-induced CPP and neuronal apoptosis in rats.

    Science.gov (United States)

    Xu, Peng; Li, Min; Bai, Yanping; Lu, Wei; Ling, Xiaomei; Li, Weidong

    2015-05-01

    Piracetam is a positive allosteric modulator of the AMPA receptor that has been used in the treatment of cognitive disorders for decades. Recent surveys and drug analyses have demonstrated that a heroin mixture adulterated with piracetam has spread rapidly in heroin addicts in China, but its addictive properties and the damage it causes to the central neural system are currently unknown. The effect of piracetam on the reward properties of heroin was assessed by conditioned place preference (CPP). Electron microscopy and radioimmunoassay were used to compare the effects of heroin mixed with equivalent piracetam (HP) and heroin alone on neuronal apoptosis and the levels of beta-endorphin (β-EP) in different brain subregions within the corticolimbic system, respectively. Piracetam significantly enhanced heroin-induced CPP expression while piracetam itself didn't induce CPP. Morphological observations showed that HP-treated rats had less neuronal apoptosis than heroin-treated group. Interestingly, HP normalized the levels of β-EP in the medial prefrontal cortex (mPFC) and core of the nucleus accumbens (AcbC) subregions, in where heroin-treated rats showed decreased levels of β-EP. These results indicate that piracetam potentiate the heroin-induced CPP and protect neurons from heroin-induced apoptosis. The protective role of HP might be related to the restoration of β-EP levels by piracetam. Our findings may provide a potential interpretation for the growing trend of HP abuse in addicts in China. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  13. Phospho-Rb mediating cell cycle reentry induces early apoptosis following oxygen-glucose deprivation in rat cortical neurons.

    Science.gov (United States)

    Yu, Ying; Ren, Qing-Guo; Zhang, Zhao-Hui; Zhou, Ke; Yu, Zhi-Yuan; Luo, Xiang; Wang, Wei

    2012-03-01

    The aim of this study was to investigate the relationship between cell cycle reentry and apoptosis in cultured cortical neurons following oxygen-glucose deprivation (OGD). We found that the percentage of neurons with BrdU uptake, TUNEL staining, and colocalized BrdU uptake and TUNEL staining was increased relative to control 6, 12 and 24 h after 1 h of OGD. The number of neurons with colocalized BrdU and TUNEL staining was decreased relative to the number of TUNEL-positive neurons at 24 h. The expression of phosphorylated retinoblastoma protein (phospho-Rb) was significantly increased 6, 12 and 24 h after OGD, parallel with the changes in BrdU uptake. Phospho-Rb and TUNEL staining were colocalized in neurons 6 and 12 h after OGD. This colocalization was strikingly decreased 24 h after OGD. Treatment with the cyclin-dependent kinase inhibitor roscovitine (100 μM) decreased the expression of phospho-Rb and reduced neuronal apoptosis in vitro. These results demonstrated that attempted cell cycle reentry with phosphorylation of Rb induce early apoptosis in neurons after OGD and there must be other mechanisms involved in the later stages of neuronal apoptosis besides cell cycle reentry. Phosphoralated Rb may be an important factor which closely associates aberrant cell cycle reentry with the early stages of neuronal apoptosis following ischemia/hypoxia in vitro, and pharmacological interventions for neuroprotection may be useful directed at this keypoint.

  14. Oxidative Stress Associated with Neuronal Apoptosis in Experimental Models of Epilepsy

    Directory of Open Access Journals (Sweden)

    Marisela Méndez-Armenta

    2014-01-01

    Full Text Available Epilepsy is considered one of the most common neurological disorders worldwide. Oxidative stress produced by free radicals may play a role in the initiation and progression of epilepsy; the changes in the mitochondrial and the oxidative stress state can lead mechanism associated with neuronal death pathway. Bioenergetics state failure and impaired mitochondrial function include excessive free radical production with impaired synthesis of antioxidants. This review summarizes evidence that suggest what is the role of oxidative stress on induction of apoptosis in experimental models of epilepsy.

  15. Apoptosis of supraoptic AVP neurons is involved in the development of central diabetes insipidus after hypophysectomy in rats

    Directory of Open Access Journals (Sweden)

    Huang Lijin

    2008-06-01

    Full Text Available Abstract Background It has been reported that various types of axonal injury of hypothalamo-neurohypophyseal tract can result in degeneration of the magnocellular neurons (MCNs in hypothalamus and development of central diabetes insipidus (CDI. However, the mechanism of the degeneration and death of MCNs after hypophysectomy in vivo is still unclear. This present study was aimed to disclose it and to figure out the dynamic change of central diabetes insipidus after hypophysectomy. Results The analysis on the dynamic change of daily water consumption (DWC, daily urine volume(DUV, specific gravity of urine(USG and plasma vasopressin concentration showed that the change pattern of them was triphasic and neuron counting showed that the degeneration of vasopressin neurons began at 10 d, aggravated at 20 d and then stabilized at 30 d after hypophysectomy. There was marked upregulation of cleaved Caspase-3 expression of vasopressin neurons in hypophysectomy rats. A "ladder" pattern of migration of DNA internucleosomal fragments was detected and apoptotic ultrastructure was found in these neurons. There was time correlation among the occurrence of diabetes insipidus, the changes of plasma vasopressin concentration and the degeneration of vasopressin neurons after hypophysectomy. Conclusion This study firstly demonstrated that apoptosis was involved in degeneration of supraoptic vasopressin neurons after hypophysectomy in vivo and development of CDI. Our study on time course and correlations among water metabolism, degeneration and apoptosis of vasopressin neurons suggested that there should be an efficient therapeutic window in which irreversible CDI might be prevented by anti-apoptosis.

  16. 14,15-EET promotes mitochondrial biogenesis and protects cortical neurons against oxygen/glucose deprivation-induced apoptosis

    International Nuclear Information System (INIS)

    Wang, Lai; Chen, Man; Yuan, Lin; Xiang, Yuting; Zheng, Ruimao; Zhu, Shigong

    2014-01-01

    Highlights: • 14,15-EET inhibits OGD-induced apoptosis in cortical neurons. • Mitochondrial biogenesis of cortical neurons is promoted by 14,15-EET. • 14,15-EET preserves mitochondrial function of cortical neurons under OGD. • CREB mediates effect of 14,15-EET on mitochondrial biogenesis and function. - Abstract: 14,15-Epoxyeicosatrienoic acid (14,15-EET), a metabolite of arachidonic acid, is enriched in the brain cortex and exerts protective effect against neuronal apoptosis induced by ischemia/reperfusion. Although apoptosis has been well recognized to be closely associated with mitochondrial biogenesis and function, it is still unclear whether the neuroprotective effect of 14,15-EET is mediated by promotion of mitochondrial biogenesis and function in cortical neurons under the condition of oxygen–glucose deprivation (OGD). In this study, we found that 14,15-EET improved cell viability and inhibited apoptosis of cortical neurons. 14,15-EET significantly increased the mitochondrial mass and the ratio of mitochondrial DNA to nuclear DNA. Key makers of mitochondrial biogenesis, peroxisome proliferator activator receptor gamma-coactivator 1 alpha (PGC-1α), nuclear respiratory factor 1 (NRF-1) and mitochondrial transcription factor A (TFAM), were elevated at both mRNA and protein levels in the cortical neurons treated with 14,15-EET. Moreover, 14,15-EET markedly attenuated the decline of mitochondrial membrane potential, reduced ROS, while increased ATP synthesis. Knockdown of cAMP-response element binding protein (CREB) by siRNA blunted the up-regulation of PGC-1α and NRF-1 stimulated by 14,15-EET, and consequently abolished the neuroprotective effect of 14,15-EET. Our results indicate that 14,15-EET protects neurons from OGD-induced apoptosis by promoting mitochondrial biogenesis and function through CREB mediated activation of PGC-1α and NRF-1

  17. 14,15-EET promotes mitochondrial biogenesis and protects cortical neurons against oxygen/glucose deprivation-induced apoptosis

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Lai; Chen, Man; Yuan, Lin; Xiang, Yuting [Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing (China); Zheng, Ruimao, E-mail: rmzheng@pku.edu.cn [Department of Anatomy, Histology and Embryology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing (China); Zhu, Shigong, E-mail: sgzhu@bjmu.edu.cn [Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing (China)

    2014-07-18

    Highlights: • 14,15-EET inhibits OGD-induced apoptosis in cortical neurons. • Mitochondrial biogenesis of cortical neurons is promoted by 14,15-EET. • 14,15-EET preserves mitochondrial function of cortical neurons under OGD. • CREB mediates effect of 14,15-EET on mitochondrial biogenesis and function. - Abstract: 14,15-Epoxyeicosatrienoic acid (14,15-EET), a metabolite of arachidonic acid, is enriched in the brain cortex and exerts protective effect against neuronal apoptosis induced by ischemia/reperfusion. Although apoptosis has been well recognized to be closely associated with mitochondrial biogenesis and function, it is still unclear whether the neuroprotective effect of 14,15-EET is mediated by promotion of mitochondrial biogenesis and function in cortical neurons under the condition of oxygen–glucose deprivation (OGD). In this study, we found that 14,15-EET improved cell viability and inhibited apoptosis of cortical neurons. 14,15-EET significantly increased the mitochondrial mass and the ratio of mitochondrial DNA to nuclear DNA. Key makers of mitochondrial biogenesis, peroxisome proliferator activator receptor gamma-coactivator 1 alpha (PGC-1α), nuclear respiratory factor 1 (NRF-1) and mitochondrial transcription factor A (TFAM), were elevated at both mRNA and protein levels in the cortical neurons treated with 14,15-EET. Moreover, 14,15-EET markedly attenuated the decline of mitochondrial membrane potential, reduced ROS, while increased ATP synthesis. Knockdown of cAMP-response element binding protein (CREB) by siRNA blunted the up-regulation of PGC-1α and NRF-1 stimulated by 14,15-EET, and consequently abolished the neuroprotective effect of 14,15-EET. Our results indicate that 14,15-EET protects neurons from OGD-induced apoptosis by promoting mitochondrial biogenesis and function through CREB mediated activation of PGC-1α and NRF-1.

  18. Sugammadex-Enhanced Neuronal Apoptosis following Neonatal Sevoflurane Exposure in Mice

    Directory of Open Access Journals (Sweden)

    Maiko Satomoto

    2016-01-01

    Full Text Available In rodents, neonatal sevoflurane exposure induces neonatal apoptosis in the brain and results in learning deficits. Sugammadex is a new selective neuromuscular blockade (NMB binding agent that anesthesiologists can use to achieve immediate reversal of an NMB with few side effects. Given its molecular weight of 2178, sugammadex is thought to be unable to pass through the blood brain barrier (BBB. Volatile anesthetics can influence BBB opening and integrity. Therefore, we investigated whether the intraperitoneal administration of sugammadex could exacerbate neuronal damage following neonatal 2% sevoflurane exposure via changes in BBB integrity. Cleaved caspase-3 immunoblotting was used to detect apoptosis, and the ultrastructure of the BBB was examined by transmission electron microscopy. Exposure to 2% sevoflurane for 6 h resulted in BBB ultrastructural abnormalities in the hippocampus of neonatal mice. Sugammadex alone without sevoflurane did not induce apoptosis. The coadministration of sugammadex with sevoflurane to neonatal mice caused a significant increase (150% in neuroapoptosis in the brain compared with 2% sevoflurane. In neonatal anesthesia, sugammadex could influence neurotoxicity together with sevoflurane. Exposure to 2% sevoflurane for 6 h resulted in BBB ultrastructural abnormalities in the hippocampus of neonatal mice.

  19. Endogenous sulfur dioxide regulates hippocampal neuron apoptosis in developing epileptic rats and is associated with the PERK signaling pathway.

    Science.gov (United States)

    Niu, Manman; Han, Ying; Li, Qinrui; Zhang, Jing

    2018-02-05

    Epilepsy is among the most common neurological diseases in children. Recurrent seizures can result in hippocampal damage and seriously impair learning and memory functions in children. However, the mechanisms underlying epilepsy-related brain injury are unclear. Neuronal apoptosis is among the most common neuropathological manifestations of brain injury. Endogenous sulfur dioxide (SO 2 ) has been shown to be involved in seizures and related neuron apoptosis. However, the role of endogenous SO 2 in epilepsy remains unclear. This study assessed whether endogenous SO 2 is involved in epilepsy and its underlying mechanisms. Using a rat epilepsy model induced by an intraperitoneal injection of kainic acid (KA), we found that hippocampal neuron apoptosis was induced in epileptic rats, and the SO 2 content and aspartate aminotransferase (AAT) activity in the plasma were increased compared to those in the control group. However, the inhibition of SO 2 production by l-aspartate-β-hydroxamate (HDX) can subvert this response 72h after an epileptic seizure. No difference in apoptosis was observed 7 d after the epileptic seizure in the KA and KA+HDX groups. The protein expression levels of AAT2, glucose-regulated protein 78 (GRP78), pancreatic eIF2 kinase-like ER kinase (PERK) and phospho-PERK (p-PERK) were remarkably elevated in the hippocampi of the epileptic rats, while the HDX treatment was capable of reversing this process 7 d after the epileptic seizure. These results indicate that the inhibition of endogenous SO 2 production can alleviate neuronal apoptosis and is associated with the PERK signaling pathway during the initial stages after epileptic seizure, but inhibiting SO 2 production only delayed the occurrence of apoptosis and did not prevent neuronal apoptosis in the epileptic rats. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Lycopene inhibits regulator of calcineurin 1-mediated apoptosis by reducing oxidative stress and down-regulating Nucling in neuronal cells.

    Science.gov (United States)

    Lim, Seiyoung; Hwang, Sinwoo; Yu, Ji Hoon; Lim, Joo Weon; Kim, Hyeyoung

    2017-05-01

    Regulator of calcineurin 1 (RCAN1) is located on the Down syndrome critical region (DSCR) locus in human chromosome 21. Oxidative stress and overexpression of RCAN1 are implicated in neuronal impairment in Down's syndrome (DS) and Alzheimer's disease (AD). Serum level of lycopene, an antioxidant pigment, is low in DS and AD patients, which may be related to neuronal damage. The present study is to investigate whether lycopene inhibits apoptosis by reducing ROS levels, NF-κB activation, expression of the apoptosis regulator Nucling, cell viability, and indices of apoptosis (cytochrome c release, caspase-3 activation) in RCAN1-overexpressing neuronal cells. Cells transfected with either pcDNA or RCAN1 were treated with or without lycopene. Lycopene decreased intracellular and mitochondrial ROS levels, NF-κB activity, and Nucling expression while it reversed decrease in mitochondrial membrane potential, mitochondrial respiration, and glycolytic function in RCAN1-overexpressing cells. Lycopene inhibited cell death, DNA fragmentation, caspase-3 activation, and cytochrome c release in RCAN1-overexpressing cells. Lycopene inhibits RCAN1-mediated apoptosis by reducing ROS levels and by inhibiting NF-κB activation, Nucling induction, and the increase in apoptotic indices in neuronal cells. Consumption of lycopene-rich foods may prevent oxidative stress-associated neuronal damage in some pathologic conditions such as DS or AD. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Curcumin protects microglia and primary rat cortical neurons against HIV-1 gp120-mediated inflammation and apoptosis.

    Directory of Open Access Journals (Sweden)

    Luyan Guo

    Full Text Available Curcumin is a molecule found in turmeric root that has anti-inflammatory, antioxidant, and anti-tumor properties and has been widely used as both an herbal drug and a food additive to treat or prevent neurodegenerative diseases. To explore whether curcumin is able to ameliorate HIV-1-associated neurotoxicity, we treated a murine microglial cell line (N9 and primary rat cortical neurons with curcumin in the presence or absence of neurotoxic HIV-1 gp120 (V3 loop protein. We found that HIV-1 gp120 profoundly induced N9 cells to produce reactive oxygen species (ROS, tumor necrosis factor-α (TNF-α and monocyte chemoattractant protein-1 (MCP-1. HIV-1 gp120 also induced apoptosis of primary rat cortical neurons. Curcumin exerted a powerful inhibitory effect against HIV-1 gp120-induced neuronal damage, reducing the production of ROS, TNF-α and MCP-1 by N9 cells and inhibiting apoptosis of primary rat cortical neurons. Curcumin may exert its biological activities through inhibition of the delayed rectification and transient outward potassium (K(+ current, as curcumin effectively reduced HIV-1 gp120-mediated elevation of the delayed rectification and transient outward K(+ channel current in neurons. We conclude that HIV-1 gp120 increases ROS, TNF-α and MCP-1 production in microglia, and induces cortical neuron apoptosis by affecting the delayed rectification and transient outward K(+ channel current. Curcumin reduces production of ROS and inflammatory mediators in HIV-1-gp120-stimulated microglia, and protects cortical neurons against HIV-1-mediated apoptosis, most likely through inhibition of HIV-1 gp120-induced elevation of the delayed rectification and transient outward K(+ current.

  2. Conditional Deletion of PDK1 in the Forebrain Causes Neuron Loss and Increased Apoptosis during Cortical Development

    Directory of Open Access Journals (Sweden)

    Congyu Xu

    2017-10-01

    Full Text Available Decreased expression but increased activity of PDK1 has been observed in neurodegenerative disease. To study in vivo function of PDK1 in neuron survival during cortical development, we generate forebrain-specific PDK1 conditional knockout (cKO mice. We demonstrate that PDK1 cKO mice display striking neuron loss and increased apoptosis. We report that PDK1 cKO mice exhibit deficits on several behavioral tasks. Moreover, PDK1 cKO mice show decreased activities for Akt and mTOR. These results highlight an essential role of endogenous PDK1 in the maintenance of neuronal survival during cortical development.

  3. Gadd45b prevents autophagy and apoptosis against rat cerebral neuron oxygen-glucose deprivation/reperfusion injury.

    Science.gov (United States)

    He, Guoqian; Xu, Wenming; Tong, Linyan; Li, Shuaishuai; Su, Shiceng; Tan, Xiaodan; Li, Changqing

    2016-04-01

    Autophagic (type II) cell death has been suggested to play pathogenetic roles in cerebral ischemia. Growth arrest and DNA damage response 45b (Gadd45b) has been shown to protect against rat brain ischemia injury through inhibiting apoptosis. However, the relationship between Gadd45b and autophagy in cerebral ischemia/reperfusion (I/R) injury remains uncertain. The aim of this study is to investigate the effect of Gadd45b on autophagy. We adopt the oxygen-glucose deprivation and reperfusion (OGD/R) model of rat primary cortex neurons, and lentivirus interference used to silence Gadd45b expression. Cell viability and injury assay were performed using CCK-8 and LDH kit. Autophagy activation was monitored by expression of ATG5, LC3, Beclin-1, ATG7 and ATG3. Neuron apoptosis was monitored by expression of Bcl-2, Bax, cleaved caspase3, p53 and TUNEL assay. Neuron neurites were assayed by double immunofluorescent labeling with Tuj1 and LC3B. Here, we demonstrated that the expression of Gadd45b was strongly up-regulated at 24 h after 3 h OGD treatment. ShRNA-Gadd45b increased the expression of autophagy related proteins, aggravated OGD/R-induced neuron cell apoptosis and neurites injury. ShRNA-Gadd45b co-treatment with autophagy inhibitor 3-methyladenine (3-MA) or Wortmannin partly inhibited the ratio of LC3II/LC3I, and slightly ameliorated neuron cell apoptosis under OGD/R. Furthermore, shRNA-Gadd45b inhibited the p-p38 level involved in autophagy, but increased the p-JNK level involved in apoptosis. ShRNA-Gadd45b co-treatment with p38 inhibitor obviously induced autophagy. ShRNA-Gadd45b co-treatment with JNK inhibitor alleviated neuron cell apoptosis. In conclusion, our data suggested that Gadd45b inhibited autophagy and apoptosis under OGD/R. Gadd45b may be a common regulatory protein to control autophagy and apoptosis.

  4. Pivotal roles of p53 transcription-dependent and -independent pathways in manganese-induced mitochondrial dysfunction and neuronal apoptosis

    Energy Technology Data Exchange (ETDEWEB)

    Wan, Chunhua [Department of Nutrition and Food Hygiene, School of Public Health, Nantong University, Nantong 226019 Jiangsu (China); Jiangsu Province Key Laboratory for Inflammation and Molecular Drug Target, Nantong University, Nantong 226019 Jiangsu (China); Ma, Xa; Shi, Shangshi [Department of Occupational Medicine and Environmental Toxicology, School of Public Health, Nantong University, Nantong 226019 Jiangsu (China); Zhao, Jianya; Nie, Xiaoke [Department of Nutrition and Food Hygiene, School of Public Health, Nantong University, Nantong 226019 Jiangsu (China); Han, Jingling; Xiao, Jing; Wang, Xiaoke [Department of Occupational Medicine and Environmental Toxicology, School of Public Health, Nantong University, Nantong 226019 Jiangsu (China); Jiang, Shengyang [Department of Nutrition and Food Hygiene, School of Public Health, Nantong University, Nantong 226019 Jiangsu (China); Jiangsu Province Key Laboratory for Inflammation and Molecular Drug Target, Nantong University, Nantong 226019 Jiangsu (China); Jiang, Junkang, E-mail: Jiang_junkang@163.com [Department of Occupational Medicine and Environmental Toxicology, School of Public Health, Nantong University, Nantong 226019 Jiangsu (China); Jiangsu Province Key Laboratory for Inflammation and Molecular Drug Target, Nantong University, Nantong 226019 Jiangsu (China)

    2014-12-15

    Chronic exposure to excessive manganese (Mn) has been known to lead to neuronal loss and a clinical syndrome resembling idiopathic Parkinson's disease (IPD). p53 plays an integral role in the development of various human diseases, including neurodegenerative disorders. However, the role of p53 in Mn-induced neuronal apoptosis and neurological deficits remains obscure. In the present study, we showed that p53 was critically involved in Mn-induced neuronal apoptosis in rat striatum through both transcription-dependent and -independent mechanisms. Western blot and immunohistochemistrical analyses revealed that p53 was remarkably upregulated in the striatum of rats following Mn exposure. Coincidentally, increased level of cleaved PARP, a hallmark of apoptosis, was observed. Furthermore, using nerve growth factor (NGF)-differentiated PC12 cells as a neuronal cell model, we showed that Mn exposure decreased cell viability and induced apparent apoptosis. Importantly, p53 was progressively upregulated, and accumulated in both the nucleus and the cytoplasm. The cytoplasmic p53 had a remarkable distribution in mitochondria, suggesting an involvement of p53 mitochondrial translocation in Mn-induced neuronal apoptosis. In addition, Mn-induced impairment of mitochondrial membrane potential (ΔΨm) could be partially rescued by pretreatment with inhibitors of p53 transcriptional activity and p53 mitochondrial translocation, Pifithrin-α (PFT-α) and Pifithrin-μ (PFT-μ), respectively. Moreover, blockage of p53 activities with PFT-α and PFT-μ significantly attenuated Mn-induced reactive oxidative stress (ROS) generation and mitochondrial H{sub 2}O{sub 2} production. Finally, we observed that pretreatment with PFT-α and PFT-μ ameliorated Mn-induced apoptosis in PC12 cells. Collectively, these findings implicate that p53 transcription-dependent and -independent pathways may play crucial roles in the regulation of Mn-induced neuronal death. - Highlights: • p53 is

  5. Pivotal roles of p53 transcription-dependent and -independent pathways in manganese-induced mitochondrial dysfunction and neuronal apoptosis

    International Nuclear Information System (INIS)

    Wan, Chunhua; Ma, Xa; Shi, Shangshi; Zhao, Jianya; Nie, Xiaoke; Han, Jingling; Xiao, Jing; Wang, Xiaoke; Jiang, Shengyang; Jiang, Junkang

    2014-01-01

    Chronic exposure to excessive manganese (Mn) has been known to lead to neuronal loss and a clinical syndrome resembling idiopathic Parkinson's disease (IPD). p53 plays an integral role in the development of various human diseases, including neurodegenerative disorders. However, the role of p53 in Mn-induced neuronal apoptosis and neurological deficits remains obscure. In the present study, we showed that p53 was critically involved in Mn-induced neuronal apoptosis in rat striatum through both transcription-dependent and -independent mechanisms. Western blot and immunohistochemistrical analyses revealed that p53 was remarkably upregulated in the striatum of rats following Mn exposure. Coincidentally, increased level of cleaved PARP, a hallmark of apoptosis, was observed. Furthermore, using nerve growth factor (NGF)-differentiated PC12 cells as a neuronal cell model, we showed that Mn exposure decreased cell viability and induced apparent apoptosis. Importantly, p53 was progressively upregulated, and accumulated in both the nucleus and the cytoplasm. The cytoplasmic p53 had a remarkable distribution in mitochondria, suggesting an involvement of p53 mitochondrial translocation in Mn-induced neuronal apoptosis. In addition, Mn-induced impairment of mitochondrial membrane potential (ΔΨm) could be partially rescued by pretreatment with inhibitors of p53 transcriptional activity and p53 mitochondrial translocation, Pifithrin-α (PFT-α) and Pifithrin-μ (PFT-μ), respectively. Moreover, blockage of p53 activities with PFT-α and PFT-μ significantly attenuated Mn-induced reactive oxidative stress (ROS) generation and mitochondrial H 2 O 2 production. Finally, we observed that pretreatment with PFT-α and PFT-μ ameliorated Mn-induced apoptosis in PC12 cells. Collectively, these findings implicate that p53 transcription-dependent and -independent pathways may play crucial roles in the regulation of Mn-induced neuronal death. - Highlights: • p53 is robustly

  6. Neuroprotective effect of ebselen against intracerebroventricular streptozotocin-induced neuronal apoptosis and oxidative stress in rats.

    Science.gov (United States)

    Unsal, Cuneyt; Oran, Mustafa; Albayrak, Yakup; Aktas, Cevat; Erboga, Mustafa; Topcu, Birol; Uygur, Ramazan; Tulubas, Feti; Yanartas, Omer; Ates, Ozkan; Ozen, Oguz Aslan

    2016-04-01

    The goal of this study was to examine the neuroprotective effect of ebselen against intracerebroventricular streptozotocin (ICV-STZ)-induced oxidative stress and neuronal apoptosis in rat brain. A total of 30 adult male Sprague-Dawley rats were randomly divided into 3 groups of 10 animals each: control, ICV-STZ, and ICV-STZ treated with ebselen. The ICV-STZ group rats were injected bilaterally with ICV-STZ (3 mg/kg) on days 1 and 3, and ebselen (10 mg/kg/day) was administered for 14 days starting from 1st day of ICV-STZ injection to day 14. Rats were killed at the end of the study and brain tissues were removed for biochemical and histopathological investigation. Our results demonstrated, for the first time, the neuroprotective effect of ebselen on Alzheimer's disease (AD) model in rats. Our present study, in ICV-STZ group, showed significant increase in tissue malondialdehyde levels and significant decrease in enzymatic antioxidants superoxide dismutase and glutathione peroxidase in the frontal cortex tissue. The histopathological studies in the brain of rats also supported that ebselen markedly reduced the ICV-STZ-induced histopathological changes and well preserved the normal histological architecture of the frontal cortex tissue. The number of apoptotic neurons was increased in frontal cortex tissue after ICV-STZ administration. Treatment of ebselen markedly reduced the number of degenerating apoptotic neurons. The study demonstrates the effectiveness of ebselen, as a powerful antioxidant, in preventing the oxidative damage and morphological changes caused by ICV-STZ in rats. Thus, ebselen may have a therapeutic value for the treatment of AD. © The Author(s) 2013.

  7. Lychee Seed Saponins Improve Cognitive Function and Prevent Neuronal Injury via Inhibiting Neuronal Apoptosis in a Rat Model of Alzheimer’s Disease

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    Xiuling Wang

    2017-02-01

    Full Text Available Lychee seed is a traditional Chinese medicine and possesses many activities, including hypoglycemia, liver protection, antioxidation, antivirus, and antitumor. However, its effect on neuroprotection is still unclear. The present study investigated the effects of lychee seed saponins (LSS on neuroprotection and associated mechanisms. We established a rat model of Alzheimer’s disease (AD by injecting Aβ25–35 into the lateral ventricle of rats and evaluated the effect of LSS on spatial learning and memory ability via the Morris water maze. Neuronal apoptosis was analyzed by hematoxylin and eosin stain and terminal deoxynucleotidyl transferase (Tdt-mediated dUTP nick-end labeling analysis, and mRNA expression of caspase-3 and protein expressions of Bax and Bcl-2 by reverse transcription-polymerase chain reaction (RT-PCR and Western blotting, respectively. The results showed that LSS remarkably improved cognitive function and alleviated neuronal injury by inhibiting apoptosis in the hippocampus of AD rats. Furthermore, the mRNA expression of caspase-3 and the protein expression of Bax were downregulated, while the protein expression of Bcl-2 and the ratio of Bcl-2/Bax were increased by LSS. We demonstrate that LSS significantly improves cognitive function and prevent neuronal injury in the AD rats via regulation of the apoptosis pathway. Therefore, LSS may be developed as a nutritional supplement and sold as a drug for AD prevention and/or treatment.

  8. 14,15-EET promotes mitochondrial biogenesis and protects cortical neurons against oxygen/glucose deprivation-induced apoptosis.

    Science.gov (United States)

    Wang, Lai; Chen, Man; Yuan, Lin; Xiang, Yuting; Zheng, Ruimao; Zhu, Shigong

    2014-07-18

    14,15-Epoxyeicosatrienoic acid (14,15-EET), a metabolite of arachidonic acid, is enriched in the brain cortex and exerts protective effect against neuronal apoptosis induced by ischemia/reperfusion. Although apoptosis has been well recognized to be closely associated with mitochondrial biogenesis and function, it is still unclear whether the neuroprotective effect of 14,15-EET is mediated by promotion of mitochondrial biogenesis and function in cortical neurons under the condition of oxygen-glucose deprivation (OGD). In this study, we found that 14,15-EET improved cell viability and inhibited apoptosis of cortical neurons. 14,15-EET significantly increased the mitochondrial mass and the ratio of mitochondrial DNA to nuclear DNA. Key makers of mitochondrial biogenesis, peroxisome proliferator activator receptor gamma-coactivator 1 alpha (PGC-1α), nuclear respiratory factor 1 (NRF-1) and mitochondrial transcription factor A (TFAM), were elevated at both mRNA and protein levels in the cortical neurons treated with 14,15-EET. Moreover, 14,15-EET markedly attenuated the decline of mitochondrial membrane potential, reduced ROS, while increased ATP synthesis. Knockdown of cAMP-response element binding protein (CREB) by siRNA blunted the up-regulation of PGC-1α and NRF-1 stimulated by 14,15-EET, and consequently abolished the neuroprotective effect of 14,15-EET. Our results indicate that 14,15-EET protects neurons from OGD-induced apoptosis by promoting mitochondrial biogenesis and function through CREB mediated activation of PGC-1α and NRF-1. Copyright © 2014 Elsevier Inc. All rights reserved.

  9. The role of metallothionein in oncogenesis and cancer treatment

    OpenAIRE

    Anna Bizoń; Kinga Jędryczko; Halina Milnerowicz

    2017-01-01

    Metallothionein is cysteine-rich low molecular mass protein. The involvement of MT in many physiological and pathophysiological processes such as apoptosis, proliferation, angiogenesis, and the detoxification of heavy metals suggested participation of this protein in carcinogenesis and tumor therapy.Depending on the type of tissue and classification of carcinoma various it was observed relation between MT expression and tumor type, stage, grade, poor prognosis and body resistance to radiother...

  10. Inhibition of apoptosis blocks human motor neuron cell death in a stem cell model of spinal muscular atrophy.

    Directory of Open Access Journals (Sweden)

    Dhruv Sareen

    Full Text Available Spinal muscular atrophy (SMA is a genetic disorder caused by a deletion of the survival motor neuron 1 gene leading to motor neuron loss, muscle atrophy, paralysis, and death. We show here that induced pluripotent stem cell (iPSC lines generated from two Type I SMA subjects-one produced with lentiviral constructs and the second using a virus-free plasmid-based approach-recapitulate the disease phenotype and generate significantly fewer motor neurons at later developmental time periods in culture compared to two separate control subject iPSC lines. During motor neuron development, both SMA lines showed an increase in Fas ligand-mediated apoptosis and increased caspase-8 and-3 activation. Importantly, this could be mitigated by addition of either a Fas blocking antibody or a caspase-3 inhibitor. Together, these data further validate this human stem cell model of SMA, suggesting that specific inhibitors of apoptotic pathways may be beneficial for patients.

  11. Intraneuronal signaling pathways of metallothionein

    DEFF Research Database (Denmark)

    Asmussen, Johanne Wirenfeldt; Von Sperling, Marie Louise; Penkowa, Milena

    2009-01-01

    Metallothionein (MT) belongs to a family of metal-binding cysteine-rich proteins comprising several structurally related proteins implicated in tissue protection and regeneration after injuries and functioning as antiapoptotic antioxidants in neurological disorders. This has been demonstrated in ...

  12. Evaluation of neuronal apoptosis precursors in an experimental model of acute normovolemic hemodilution.

    Directory of Open Access Journals (Sweden)

    Fabrício O Frazilio

    Full Text Available The effects of acute anemia on neuronal cells and the safe limits of hematocrit are not well established. The objective of this study was to evaluate neuronal pro- and anti-apoptotic Bax and Bcl-x proteins, caspase-3 and -9 activity, and DNA fragmentation after acute normovolemic hemodilution (ANH.Twenty-four pigs were anesthetized and randomized into 4 groups: Sham, ANH to 15% hematocrit (ANH15%, ANH to 10% hematocrit (ANH10% and hypoxia (Hx. ANH was achieved by simultaneous blood withdrawal and hydroxyethyl starch infusion. Hx consisted of ventilation with a 6% inspired oxygen fraction for 60 minutes. Bax and Bcl-x proteins as well as DNA fragmentation were evaluated in cortical nuclear and mitochondrial fractions. Caspase-3 and -9 activity was evaluated in the cortical mitochondrial and hippocampal cytosolic fractions. The data were compared using analysis of variance followed by Tukey's test (P<0.05.No changes were observed in Bax protein expression after hemodilution in the ANH15% and ANH10% groups compared to the Sham group. Bax expression in the Hx group was increased in the nuclear and mitochondrial fractions compared to all other groups. No significant difference was observed in Bcl-x expression. Caspase-3 and -9 activity in the cytosolic and mitochondrial fractions was different in the Hx group compared to all other groups. No statistical significance in DNA fragmentation was found among the Sham, ANH15% or ANH10% groups.ANH to 10 and 15% hematocrit did not induce alterations in apoptosis precursors, suggesting that cerebral oxygenation was preserved during these anemic states.

  13. PirB Overexpression Exacerbates Neuronal Apoptosis by Inhibiting TrkB and mTOR Phosphorylation After Oxygen and Glucose Deprivation Injury.

    Science.gov (United States)

    Zhao, Zhao-Hua; Deng, Bin; Xu, Hao; Zhang, Jun-Feng; Mi, Ya-Jing; Meng, Xiang-Zhong; Gou, Xing-Chun; Xu, Li-Xian

    2017-05-01

    Previous studies have proven that paired immunoglobulin-like receptor B (PirB) plays a crucial suppressant role in neurite outgrowth and neuronal plasticity after central nervous system injury. However, the role of PirB in neuronal survival after cerebral ischemic injury and its mechanisms remains unclear. In the present study, the role of PirB is investigated in the survival and apoptosis of cerebral cortical neurons in cultured primary after oxygen and glucose deprivation (OGD)-induced injury. The results have shown that rebarbative PirB exacerbates early neuron apoptosis and survival. PirB gene silencing remarkably decreases early apoptosis and promotes neuronal survival after OGD. The expression of bcl-2 markedly increased and the expression of bax significantly decreased in PirB RNAi-treated neurons, as compared with the control- and control RNAi-treated ones. Further, phosphorylated TrkB and mTOR levels are significantly downregulated in the damaged neurons. However, the PirB silencing markedly upregulates phosphorylated TrkB and mTOR levels in the neurons after the OGD. Taken together, the overexpression of PirB inhibits the neuronal survival through increased neuron apoptosis. Importantly, the inhibition of the phosphorylation of TrkB and mTOR may be one of its mechanisms.

  14. Metallothionein treatment reduces proinflammatory cytokines IL-6 and TNF-alpha and apoptotic cell death during experimental autoimmune encephalomyelitis (EAE)

    DEFF Research Database (Denmark)

    Penkowa, M; Hidalgo, J

    2001-01-01

    cytokines and apoptosis during EAE could contribute to the reported diminution of clinical symptoms and mortality in EAE-immunized rats receiving Zn-MT-II treatment. Our results demonstrate that MT-II reduces the CNS expression of proinflammatory cytokines and the number of apoptotic neurons during EAE......, which is characterized by significant inflammation and neuroglial damage. We have recently shown that the exogenous administration of the antioxidant protein zinc-metallothionein-II (Zn-MT-II) significantly decreased the clinical symptoms, mortality, and leukocyte infiltration of the CNS during EAE....... However, it is not known how EAE progression is regulated nor how cytokine production and cell death can be reduced. We herewith demonstrate that treatment with Zn-MT-II significantly decreased the CNS expression of IL-6 and TNF-alpha during EAE. Zn-MT-II treatment could also significantly reduce...

  15. Edaravone attenuates neuronal apoptosis in hypoxic-ischemic brain damage rat model via suppression of TRAIL signaling pathway.

    Science.gov (United States)

    Li, Chunyi; Mo, Zhihuai; Lei, Junjie; Li, Huiqing; Fu, Ruying; Huang, Yanxia; Luo, Shijian; Zhang, Lei

    2018-06-01

    Edaravone is a new type of oxygen free radical scavenger and able to attenuate various brain damage including hypoxic-ischemic brain damage (HIBD). This study was aimed at investigating the neuroprotective mechanism of edaravone in rat hypoxic-ischemic brain damage model and its correlation with tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) signaling pathway. 75 seven-day-old Sprague-Dawley neonatal rats were equally divided into three groups: sham-operated group (sham), HIBD group and HIBD rats injected with edaravone (HIBD + EDA) group. Neurological severity and space cognitive ability of rats in each group were evaluated using Longa neurological severity score and Morris water maze testing. TUNEL assay and flow cytometry were used to determine brain cell apoptosis. Western blot was used to estimate the expression level of death receptor-5 (DR5), Fas-associated protein with death domain (FADD), caspase 8, B-cell lymphoma-2 (Bcl-2) and Bcl-2 associated X protein (Bax). In addition, immunofluorescence was performed to detect caspase 3. Edaravone reduced neurofunctional damage caused by HIBD and improved the cognitive capability of rats. The above experiment results suggested that edaravone could down-regulate the expression of active caspase 3 protein, thereby relieving neuronal apoptosis. Taken together, edaravone could attenuate neuronal apoptosis in rat hypoxic-ischemic brain damage model via suppression of TRAIL signaling pathway, which also suggested that edaravone might be an effective therapeutic strategy for HIBD clinical treatment. Copyright © 2018 Elsevier Ltd. All rights reserved.

  16. Dietary flavonoid fisetin regulates aluminium chloride-induced neuronal apoptosis in cortex and hippocampus of mice brain.

    Science.gov (United States)

    Prakash, Dharmalingam; Sudhandiran, Ganapasam

    2015-12-01

    Dietary flavonoids have been suggested to promote brain health by protecting brain parenchymal cells. Recently, understanding the possible mechanism underlying neuroprotective efficacy of flavonoids is of great interest. Given that fisetin exerts neuroprotection, we have examined the mechanisms underlying fisetin in regulating Aβ aggregation and neuronal apoptosis induced by aluminium chloride (AlCl3) administration in vivo. Male Swiss albino mice were induced orally with AlCl3 (200 mg/kg. b.wt./day/8 weeks). Fisetin (15 mg/Kg. b.wt. orally) was administered for 4 weeks before AlCl3-induction and administered simultaneously for 8 weeks during AlCl3-induction. We found aggregation of Amyloid beta (Aβ 40-42), elevated expressions of Apoptosis stimulating kinase (ASK-1), p-JNK (c-Jun N-terminal Kinase), p53, cytochrome c, caspases-9 and 3, with altered Bax/Bcl-2 ratio in favour of apoptosis in cortex and hippocampus of AlCl3-administered mice. Furthermore, TUNEL and fluoro-jade C staining demonstrate neurodegeneration in cortex and hippocampus. Notably, treatment with fisetin significantly (Pfisetin treatment. We have identified the involvement of fisetin in regulating ASK-1 and p-JNK as possible mediator of Aβ aggregation and subsequent neuronal apoptosis during AlCl3-induced neurodegeneration. These findings define the possibility that fisetin may slow or prevent neurodegneration and can be utilised as neuroprotective agent against Alzheimer's and Parkinson's disease. Copyright © 2015 Elsevier Inc. All rights reserved.

  17. Protective effect of nicotinamide adenine dinucleotide (NAD+) against spinal cord ischemia-reperfusion injury via reducing oxidative stress-induced neuronal apoptosis.

    Science.gov (United States)

    Xie, Lei; Wang, Zhenfei; Li, Changwei; Yang, Kai; Liang, Yu

    2017-02-01

    As previous studies demonstrate that oxidative stress and apoptosis play crucial roles in ischemic pathogenesis and nicotinamide adenine dinucleotide (NAD + ) treatment attenuates oxidative stress-induced cell death among primary neurons and astrocytes as well as significantly reduce cerebral ischemic injury in rats. We used a spinal cord ischemia injury (SCII) model in rats to verify our hypothesis that NAD + could ameliorate oxidative stress-induced neuronal apoptosis. Adult male rats were subjected to transient spinal cord ischemia for 60min, and different doses of NAD + were administered intraperitoneally immediately after the start of reperfusion. Neurological function was determined by Basso, Beattie, Bresnahan (BBB) scores. The oxidative stress level was assessed by superoxide dismutase (SOD) activity and malondialdehyde (MDA) content. The degree of apoptosis was analyzed by deoxyuridinetriphosphate nick-end labeling (TUNEL) staining and protein levels of cleaved caspase-3 and AIF (apoptosis inducing factor). The results showed that NAD + at 50 or 100mg/kg significantly decreased the oxidative stress level and neuronal apoptosis in the spinal cord of ischemia-reperfusion rats compared with saline, as accompanied with the decreased oxidative stress, NAD + administration significantly restrained the neuronal apoptosis after ischemia injury while improved the neurological and motor function. These findings suggested that NAD + might protect against spinal cord ischemia-reperfusion via reducing oxidative stress-induced neuronal apoptosis. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Role of metallothionein-III following central nervous system damage

    DEFF Research Database (Denmark)

    Carrasco, Javier; Penkowa, Milena; Giralt, Mercedes

    2003-01-01

    We evaluated the physiological relevance of metallothionein-III (MT-III) in the central nervous system following damage caused by a focal cryolesion onto the cortex by studying Mt3-null mice. In normal mice, dramatic astrogliosis and microgliosis and T-cell infiltration were observed in the area...... the inflammatory response elicited in the central nervous system by a cryoinjury, nor does it serve an important antioxidant role, but it may influence neuronal regeneration during the recovery process....

  19. Ceramides in Alzheimer’s Disease: Key Mediators of Neuronal Apoptosis Induced by Oxidative Stress and Aβ Accumulation

    Directory of Open Access Journals (Sweden)

    Maja Jazvinšćak Jembrek

    2015-01-01

    Full Text Available Alzheimer’s disease (AD, the most common chronic and progressive neurodegenerative disorder, is characterized by extracellular deposits of amyloid β-peptides (Aβ and intracellular deposits of hyperphosphorylated tau (phospho-tau protein. Ceramides, the major molecules of sphingolipid metabolism and lipid second messengers, have been associated with AD progression and pathology via Aβ generation. Enhanced levels of ceramides directly increase Aβ through stabilization of β-secretase, the key enzyme in the amyloidogenic processing of Aβ precursor protein (APP. As a positive feedback loop, the generated oligomeric and fibrillar Aβ induces a further increase in ceramide levels by activating sphingomyelinases that catalyze the catabolic breakdown of sphingomyelin to ceramide. Evidence also supports important role of ceramides in neuronal apoptosis. Ceramides may initiate a cascade of biochemical alterations, which ultimately leads to neuronal death by diverse mechanisms, including depolarization and permeabilization of mitochondria, increased production of reactive oxygen species (ROS, cytochrome c release, Bcl-2 depletion, and caspase-3 activation, mainly by modulating intracellular signalling, particularly along the pathways related to Akt/PKB kinase and mitogen-activated protein kinases (MAPKs. This review summarizes recent findings related to the role of ceramides in oxidative stress-driven neuronal apoptosis and interplay with Aβ in the cascade of events ending in neuronal degeneration.

  20. [Effects of perinatal exposure to bisphenol A inducing dopaminergic neuronal cell to apoptosis happening in midbrain of male rat offspring].

    Science.gov (United States)

    Lin, Yong; Zhang, Hao; Wang, Wen-dong; Wu, De-sheng; Jiang, Song-hui; Qu, Wei-dong

    2006-07-01

    To investigate the mechanism and effect of rat perinatal exposure to bisphenol A (BPA) resulting in midbrain dopaminergic neuronal cell apoptosis and tyrosine hydroxylase expression of male offspring. Rat dams were randomLy divided into 4 groups on gestational day(GD) 10 and given orally the bisphenol A doses as 0, 0.5, 5, 50 mg/kg x d from GD10 to weaning. The brains of male offspring were obtained for detecting, with immunohistochemistry protocol, the Caspase-3, Bcl-2 and tyrosine hydroxylase expression in the midbrain on postnatal day 21 or 30 respectively, and the midbrain apoptotic neuronal cell were detected by TUNEL on PND21. The expression of Caspase-3 in the midbrain of rat male offspring were increased but bcl-2 were decreased on PND21 and 30, respectively. On PND21, apoptotic neuronal cell were found in the midbrain of high and medium doses groups. TH protein expression was decreased. Perinatal exposure to bisphenol A can induce the apoptosis of midbrain dopaminergic neuron in the male rat offspring even after weaning, and concomitantly decrease the midbrain TH immunoreactivity, this may cause the abnormal function of dopaminergic pathway of rat male offspring.

  1. Hypoxia promotes apoptosis of neuronal cells through hypoxia-inducible factor-1α-microRNA-204-B-cell lymphoma-2 pathway.

    Science.gov (United States)

    Wang, Xiuwen; Li, Ji; Wu, Dongjin; Bu, Xiangpeng; Qiao, Yong

    2016-01-01

    Neuronal cells are highly sensitive to hypoxia and may be subjected to apoptosis when exposed to hypoxia. Several apoptosis-related genes and miRNAs involve in hypoxia-induced apoptosis. This study aimed to examine the role of HIF1α-miR-204-BCL-2 pathway in hypoxia-induced apoptosis in neuronal cells. Annexin V/propidium iodide assay was performed to analyze cell apoptosis in AGE1.HN and PC12 cells under hypoxic or normoxic conditions. The expression of BCL-2 and miR-204 were determined by Western blot and qRT-PCR. The effects of miR-204 overexpression or knockdown on the expression of BCL-2 were evaluated by luciferase assay and Western blot under hypoxic or normoxic conditions. HIF-1α inhibitor YC-1 and siHIF-1α were employed to determine the effect of HIF-1α on the up-regulation of miR-204 and down-regulation of BCL-2 induced by hypoxia. Apoptosis assay showed the presence of apoptosis induced by hypoxia in neuronal cells. Moreover, we found that hypoxia significantly down-regulated the expression of BCL-2, and increased the mRNA level of miR-204 in neuronal cells than that in control. Bioinformatic analysis and luciferase reporter assay demonstrated that miR-204 directly targeted and regulated the expression of BCL-2. Specifically, the expression of BCL-2 was inhibited by miR-204 mimic and enhanced by miR-204 inhibitor. Furthermore, we detected that hypoxia induced cell apoptosis via HIF-1α/miR-204/BCL-2 in neuronal cells. This study demonstrated that HIF-1α-miR-204-BCL-2 pathway contributed to apoptosis of neuronal cells induced by hypoxia, which could potentially be exploited to prevent spinal cord ischemia-reperfusion injury. © 2015 by the Society for Experimental Biology and Medicine.

  2. Bovine Herpes Virus 1 (BHV-1) and Herpes Simplex Virus Type 1 (HSV-1) Promote Survival of Latently Infected Sensory Neurons, in Part by Inhibiting Apoptosis

    Science.gov (United States)

    Jones, Clinton

    2013-01-01

    α-Herpesvirinae subfamily members, including herpes simplex virus type 1 (HSV-1) and bovine herpes virus 1 (BHV-1), initiate infection in mucosal surfaces. BHV-1 and HSV-1 enter sensory neurons by cell-cell spread where a burst of viral gene expression occurs. When compared to non-neuronal cells, viral gene expression is quickly extinguished in sensory neurons resulting in neuronal survival and latency. The HSV-1 latency associated transcript (LAT), which is abundantly expressed in latently infected neurons, inhibits apoptosis, viral transcription, and productive infection, and directly or indirectly enhances reactivation from latency in small animal models. Three anti-apoptosis genes can be substituted for LAT, which will restore wild type levels of reactivation from latency to a LAT null mutant virus. Two small non-coding RNAs encoded by LAT possess anti-apoptosis functions in transfected cells. The BHV-1 latency related RNA (LR-RNA), like LAT, is abundantly expressed during latency. The LR-RNA encodes a protein (ORF2) and two microRNAs that are expressed in certain latently infected neurons. Wild-type expression of LR gene products is required for stress-induced reactivation from latency in cattle. ORF2 has anti-apoptosis functions and interacts with certain cellular transcription factors that stimulate viral transcription and productive infection. ORF2 is predicted to promote survival of infected neurons by inhibiting apoptosis and sequestering cellular transcription factors which stimulate productive infection. In addition, the LR encoded microRNAs inhibit viral transcription and apoptosis. In summary, the ability of BHV-1 and HSV-1 to interfere with apoptosis and productive infection in sensory neurons is crucial for the life-long latency-reactivation cycle in their respective hosts. PMID:25278776

  3. Ghrelin Attenuates Retinal Neuronal Autophagy and Apoptosis in an Experimental Rat Glaucoma Model.

    Science.gov (United States)

    Zhu, Ke; Zhang, Meng-Lu; Liu, Shu-Ting; Li, Xue-Yan; Zhong, Shu-Min; Li, Fang; Xu, Ge-Zhi; Wang, Zhongfeng; Miao, Yanying

    2017-12-01

    Ghrelin, a natural ligand for the growth hormone secretagogue receptor type 1a (GHSR-1a), may protect retinal neurons against glaucomatous injury. We therefore characterized the underlying mechanism of the ghrelin/GHSR-1a-mediated neuroprotection with a rat chronic intraocular hypertension (COH) model. The rat COH model was produced by blocking episcleral veins. A combination of immunohistochemistry, Western blot, TUNEL assay, and retrograde labeling of retinal ganglion cells (RGCs) was used. Elevation of intraocular pressure induced a significant increase in ghrelin and GHSR-1a expression in retinal cells, including RGCs and Müller cells. Western blot confirmed that the protein levels of ghrelin exhibited a transient upregulation at week 2 after surgery (G2w), while the GHSR-1a protein levels were maintained at high levels from G2w to G4w. In COH retinas, the ratio of LC3-II/LC-I and beclin1, two autophagy-related proteins, were increased from G1w to G4w, and the cleavage product of caspase3, an apoptotic executioner, was detected from G2w to G4w. Intraperitoneal injection of ghrelin significantly increased the number of surviving RGCs; inhibited the changes of LC3-II/LC-I, beclin1, and the cleavage products of caspase3; and reduced the number of TUNEL-positive cells in COH retinas. Ghrelin treatment also reversed the decreased levels of p-Akt and p-mTOR, upregulated GHSR-1a protein levels, and attenuated glial fibrillary acidic protein levels in COH retinas. All these results suggest that ghrelin may provide neuroprotective effect in COH retinas through activating ghrelin/GHSR-1a system, which was mediated by inhibiting retinal autophagy, ganglion cell apoptosis, and Müller cell gliosis.

  4. Effect of ketamine on aquaporin-4 expression and neuronal apoptosis in brain tissues following brain injury in rats

    Institute of Scientific and Technical Information of China (English)

    Zangong Zhou; Xiangyu Ji; Li Song; Jianfang Song; Shiduan Wang; Yanwei Yin

    2006-01-01

    BACKGROUND: Aquaporin-4 (AQP-4) is closely related to the formation of brain edema. Neuronal apoptosis plays an important part in the conversion of swelled neuron following traumatic brain injury. At present, the studies on the protective effect of ketamine on brain have involved in its effect on aquaporin-4 expression and neuronal apoptosis in the brain tissues following brain injury in rats.OBJECTIVE: To observe the effect of ketamine on AQP-4 expression and neuronal apoptosis in the brain tissue following rat brain injury, and analyze the time-dependence of ketamine in the treatment of brain injury.DESIGN: Randomized grouping design, controlled animal trial.SETTING: Department of Anesthesiology, the Medical School Hospital of Qingdao University.MATERIALS: Totally 150 rats of clean grade, aged 3 months, were involved and randomized into control group and ketamine-treated group, with 75 rats in each. Each group was divided into 5 subgroups separately at 6,12, 24, 48 and 72 hours after injury, with 15 rats at each time point. Main instruments and reagents:homemade beat machine, ketamine hydrochloride (Hengrui Pharmaceutical Factory, Jiangsu), rabbit anti-rat AQP-4 polyclonal antibody, SABC immunohistochemical reagent kit and TUNEL reagent kit (Boster Co.,Ltd.,Wuhan).METHODS: This trial was carried out in the Institute of Cerebrovascular Disease, Medical College of Qingdao University during March 2005 to February 2006. A weight-dropping rat model of brain injury was created with Feeney method. The rats in the ketamine-treated group were intraperitoneally administered with 50 g/L ketamine (120 mg/kg) one hour after injury, but ketamine was replaced by normal saline in the control group. In each subgroup, the water content of cerebral hemisphere was measured in 5 rats chosen randomly. The left 10 rats in each subgroup were transcardiacally perfused with ketamine, then the brain tissue was made into paraffin sections and stained by haematoxylin and eosin. Neuronal

  5. Identification of ASK1, MKK4, JNK, c-Jun, and caspase-3 as a signaling cascade involved in cadmium-induced neuronal cell apoptosis

    International Nuclear Information System (INIS)

    Kim, Sun Don; Moon, Chang Kyu; Eun, Su-Yong; Ryu, Pan Dong; Jo, Sangmee Ahn

    2005-01-01

    Cd induces oxidative stress and apoptosis in various cells by activating mitogen-activated protein kinases (MAPKs), but the precise signaling components of the MAPK cascade and their role in neuronal apoptosis are still unclear. Here, we report that Cd treatment of SH-SY5Y cells caused apoptosis through sequential phosphorylation of the apoptosis signal regulating kinase 1, MAPK kinase 4, c-Jun N-terminal kinase (JNK), and c-Jun as determined by overexpression of dominant negative (DN) constructs of these genes or using a specific JNK inhibitor SP600125. Both Cd-induced JNK and c-Jun phosphorylation and apoptosis were inhibited dramatically by N-acetyl-L-cysteine, a free radical scavenger. In addition, caspase inhibitors, zDEVD and zVAD, reduced apoptosis but not JNK and c-Jun phosphorylation induced by Cd, while overexpression of DN JNK1 inhibited caspase-3 activity. Taken together, our data suggested that the JNK/c-Jun signaling cascade plays a crucial role in Cd-induced neuronal cell apoptosis and provides a molecular linkage between oxidative stress and neuronal apoptosis

  6. Protein misfolding cyclic amplification induces the conversion of recombinant prion protein to PrP oligomers causing neuronal apoptosis.

    Science.gov (United States)

    Yuan, Zhen; Yang, Lifeng; Chen, Baian; Zhu, Ting; Hassan, Mohammad Farooque; Yin, Xiaomin; Zhou, Xiangmei; Zhao, Deming

    2015-06-01

    The formation of neurotoxic prion protein (PrP) oligomers is thought to be a key step in the development of prion diseases. Recently, it was determined that the sonication and shaking of recombinant PrP can convert PrP monomers into β-state oligomers. Herein, we demonstrate that β-state oligomeric PrP can be generated through protein misfolding cyclic amplification from recombinant full-length hamster, human, rabbit, and mutated rabbit PrP, and that these oligomers can be used for subsequent research into the mechanisms of PrP-induced neurotoxicity. We have characterized protein misfolding cyclic amplification-induced monomer-to-oligomer conversion of PrP from three species using western blotting, circular dichroism, size-exclusion chromatography, and resistance to proteinase K (PK) digestion. We have further shown that all of the resulting β-oligomers are toxic to primary mouse cortical neurons independent of the presence of PrP(C) in the neurons, whereas the corresponding monomeric PrP were not toxic. In addition, we found that this toxicity is the result of oligomer-induced apoptosis via regulation of Bcl-2, Bax, and caspase-3 in both wild-type and PrP(-/-) cortical neurons. It is our hope that these results may contribute to our understanding of prion transformation within the brain. We found that β-state oligomeric PrPs can be generated through protein misfolding cyclic amplification (PMCA) from recombinant full-length hamster, human, rabbit, and mutated rabbit PrP. β-oligomers are toxic to primary mouse cortical neurons independent of the presence of PrP(C) in the neurons, while the corresponding monomeric PrPs were not toxic. This toxicity is the result of oligomers-induced apoptosis via regulation of Bcl-2, Bax, and caspase-3. These results may contribute to our understanding of prion transformation within the brain. © 2015 International Society for Neurochemistry.

  7. Ischemia leads to apoptosis--and necrosis-like neuron death in the ischemic rat hippocampus

    DEFF Research Database (Denmark)

    Müller, Georg Johannes; Stadelmann, Christine; Bastholm, Lone

    2004-01-01

    necrosis; its expression peaked on days 3 to 4. Silver staining for nucleoli, which are a substrate for caspase-3, revealed a profound loss of nucleoli in cells with apoptosis-like morphology, whereas cells with necrosis-like morphology showed intact nucleoli. Overall, cells with apoptosis-like morphology...

  8. Autophagy and apoptosis are differentially induced in neurons and astrocytes treated with an in vitro mimic of the ischemic penumbra.

    Directory of Open Access Journals (Sweden)

    Matthew E Pamenter

    Full Text Available The development of clinical stroke therapies remains elusive. The neuroprotective efficacies of thousands of molecules and compounds have not yet been determined; however, screening large volumes of potential targets in vivo is severely rate limiting. High throughput screens (HTS may be used to discover promising candidates, but this approach has been hindered by the lack of a simple in vitro model of the ischemic penumbra, a clinically relevant region of stroke-afflicted brain. Recently, our laboratory developed such a mimic (ischemic solution: IS suitable for HTS, but the etiology of stress pathways activated by this model are poorly understood. The aim of the present study was to determine if the cell death phenotype induced by IS accurately mimics the in vivo penumbra and thus whether our model system is suitable for use in HTS. We treated cultured neuron and astrocyte cell lines with IS for up to 48 hrs and examined cellular energy state ([ATP], cell and organelle morphology, and gene and molecular profiles related to stress pathways. We found that IS-treated cells exhibited a phenotype of mixed apoptosis/autophagy characteristic of the in vivo penumbra, including: (1 short-term elevation of [ATP] followed by progressive ATP depletion and Poly ADP Ribose Polymerase cleavage, (2 increased vacuole number in the cytoplasm, (3 mitochondrial rupture, decreased mitochondrial and cristae density, release of cytochrome C and apoptosis inducing factor, (4 chromatin condensation, nuclear lamin A and DNA cleavage, fragmentation of the nuclear envelope, and (5 altered expression of mRNA and proteins consistent with autophagy and apoptosis. We conclude that our in vitro model of the ischemic penumbra induces autophagy and apoptosis in cultured neuron and astrocyte cell lines and that this mimic solution is suitable for use in HTS to elucidate neuroprotective candidates against ischemic penumbral cell death.

  9. Human recombinant factor VIIa may improve heat intolerance in mice by attenuating hypothalamic neuronal apoptosis and damage.

    Science.gov (United States)

    Hsu, Chuan-Chih; Chen, Sheng-Hsien; Lin, Cheng-Hsien; Yung, Ming-Chi

    2014-10-01

    Intolerance to heat exposure is believed to be associated with hypothalamo-pituitary-adrenocortical (HPA) axis impairment [reflected by decreases in blood concentrations of both adrenocorticotrophic-hormone (ACTH) and corticosterone]. The purpose of this study was to determine the effect of human recombinant factor VIIa (rfVIIa) on heat intolerance, HPA axis impairment, and hypothalamic inflammation, ischemic and oxidative damage, and apoptosis in mice under heat stress. Immediately after heat stress (41.2 °C for 1 h), mice were treated with vehicle (1 mL/kg of body weight) or rfVIIa (65-270 µg/kg of body weight) and then returned to room temperature (26 °C). Mice still alive on day 4 of heat exposure were considered survivors. Cellular ischemia markers (e.g., glutamate, lactate-to-pyruvate ratio), oxidative damage markers (e.g., nitric oxide metabolite, hydroxyl radials), and pro-inflammatory cytokines (e.g., interleukin-6, interleukin-1β, tumor necrosis factor-α) in hypothalamus were determined. In addition, blood concentrations of both ACTH and corticosterone were measured. Hypothalamic cell damage was assessed by determing the neuronal damage scores, whereas the hypothalamic cell apoptosis was determined by assessing the numbers of cells stained with terminal deoxynucleotidyl transferase-mediated αUTP nick-end labeling, caspase-3-positive cells, and platelet endothelial cell adhesion molecula-1-positive cells in hypothalamus. Compared with vehicle-treated heated mice, rfVIIa-treated heated mice had significantly higher fractional survival (8/10 vs 1/10), lesser thermoregulatory deficit (34.1 vs 24.8 °C), lesser extents of ischemic, oxidative, and inflammatory markers in hypothalamus, lesser neuronal damage scores and apoptosis in hypothalamus, and lesser HPA axis impairment. Human recombinant factor VIIa appears to exert a protective effect against heatstroke by attenuating hypothalamic cell apoptosis (due to ischemic, inflammatory, and oxidative damage

  10. Motor neuron apoptosis and neuromuscular junction perturbation are prominent features in a Drosophila model of Fus-mediated ALS

    Science.gov (United States)

    2012-01-01

    Backgound Amyotrophic lateral sclerosis (ALS) is progressive neurodegenerative disease characterized by the loss of motor function. Several ALS genes have been identified as their mutations can lead to familial ALS, including the recently reported RNA-binding protein fused in sarcoma (Fus). However, it is not clear how mutations of Fus lead to motor neuron degeneration in ALS. In this study, we present a Drosophila model to examine the toxicity of Fus, its Drosophila orthologue Cabeza (Caz), and the ALS-related Fus mutants. Results Our results show that the expression of wild-type Fus/Caz or FusR521G induced progressive toxicity in multiple tissues of the transgenic flies in a dose- and age-dependent manner. The expression of Fus, Caz, or FusR521G in motor neurons significantly impaired the locomotive ability of fly larvae and adults. The presynaptic structures in neuromuscular junctions were disrupted and motor neurons in the ventral nerve cord (VNC) were disorganized and underwent apoptosis. Surprisingly, the interruption of Fus nuclear localization by either deleting its nuclear localization sequence (NLS) or adding a nuclear export signal (NES) blocked Fus toxicity. Moreover, we discovered that the loss of caz in Drosophila led to severe growth defects in the eyes and VNCs, caused locomotive disability and NMJ disruption, but did not induce apoptotic cell death. Conclusions These data demonstrate that the overexpression of Fus/Caz causes in vivo toxicity by disrupting neuromuscular junctions (NMJs) and inducing apoptosis in motor neurons. In addition, the nuclear localization of Fus is essential for Fus to induce toxicity. Our findings also suggest that Fus overexpression and gene deletion can cause similar degenerative phenotypes but the underlying mechanisms are likely different. PMID:22443542

  11. Motor neuron apoptosis and neuromuscular junction perturbation are prominent features in a Drosophila model of Fus-mediated ALS

    Directory of Open Access Journals (Sweden)

    Xia Ruohan

    2012-03-01

    Full Text Available Abstract Backgound Amyotrophic lateral sclerosis (ALS is progressive neurodegenerative disease characterized by the loss of motor function. Several ALS genes have been identified as their mutations can lead to familial ALS, including the recently reported RNA-binding protein fused in sarcoma (Fus. However, it is not clear how mutations of Fus lead to motor neuron degeneration in ALS. In this study, we present a Drosophila model to examine the toxicity of Fus, its Drosophila orthologue Cabeza (Caz, and the ALS-related Fus mutants. Results Our results show that the expression of wild-type Fus/Caz or FusR521G induced progressive toxicity in multiple tissues of the transgenic flies in a dose- and age-dependent manner. The expression of Fus, Caz, or FusR521G in motor neurons significantly impaired the locomotive ability of fly larvae and adults. The presynaptic structures in neuromuscular junctions were disrupted and motor neurons in the ventral nerve cord (VNC were disorganized and underwent apoptosis. Surprisingly, the interruption of Fus nuclear localization by either deleting its nuclear localization sequence (NLS or adding a nuclear export signal (NES blocked Fus toxicity. Moreover, we discovered that the loss of caz in Drosophila led to severe growth defects in the eyes and VNCs, caused locomotive disability and NMJ disruption, but did not induce apoptotic cell death. Conclusions These data demonstrate that the overexpression of Fus/Caz causes in vivo toxicity by disrupting neuromuscular junctions (NMJs and inducing apoptosis in motor neurons. In addition, the nuclear localization of Fus is essential for Fus to induce toxicity. Our findings also suggest that Fus overexpression and gene deletion can cause similar degenerative phenotypes but the underlying mechanisms are likely different.

  12. O-GlcNAcylation regulates ischemia-induced neuronal apoptosis through AKT signaling

    OpenAIRE

    Shi, Jianhua; Gu, Jin-hua; Dai, Chun-ling; Gu, Jianlan; Jin, Xiaoxia; Sun, Jianming; Iqbal, Khalid; Liu, Fei; Gong, Cheng-Xin

    2015-01-01

    Apoptosis plays an important role in neural development and neurological disorders. In this study, we found that O-GlcNAcylation, a unique protein posttranslational modification with O-linked β-N-acetylglucosamine (GlcNAc), promoted apoptosis through attenuating phosphorylation/activation of AKT and Bad. By using co-immunoprecipitation and mutagenesis techniques, we identified O-GlcNAc modification at both Thr308 and Ser473 of AKT. O-GlcNAcylation-induced apoptosis was attenuated by over-expr...

  13. Neuronal apoptosis and neurofilament protein expression in the lateral geniculate body of cats following acute optic nerve injuries

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    BACKGROUND: The visual pathway have 6 parts, involving optic nerve, optic chiasm, optic tract, lateral geniculate body, optic radiation and cortical striatum area. Corresponding changes may be found in these 6 parts following optic nerve injury. At present, studies mainly focus on optic nerve and retina, but studies on lateral geniculate body are few.OBJECTIVE: To prepare models of acute optic nerve injury for observing the changes of neurons in lateral geniculate body, expression of neurofilament protein at different time after injury and cell apoptosis under the optical microscope, and for investigating the changes of neurons in lateral geniculate body following acute optic nerve injury.DESIGN: Completely randomized grouping design, controlled animal experiment.SETTING: Department of Neurosurgery, General Hospital of Ji'nan Military Area Command of Chinese PLA.MATERIALS: Twenty-eight adult healthy cats of either gender and common grade, weighing from 2.0 to 3.5 kg, were provided by the Animal Experimental Center of Fudan University. The involved cats were divided into 2 groups according to table of random digit: normal control group (n =3) and model group (n =25). Injury 6 hours, 1, 3, 7 and 14 days five time points were set in model group for later observation, 5 cats at each time point. TUNEL kit (Bohringer-Mannheim company)and NF200& Mr 68 000 mouse monoclonal antibody (NeoMarkers Company) were used in this experiment.METHODS: This experiment was carried out in the Department of Neurosurgery, General Hospital of Ji'nan Military Area Command of Chinese PLA between June 2004 and June 2005. ① The cats of model group were developed into cat models of acute intracranial optic nerve injury as follows: The anesthetized cats were placed in lateral position. By imitating operation to human, pterion approach was used. An incision was made at the joint line between outer canthus and tragus, and deepened along cranial base until white optic nerve via optic nerve pore

  14. Metallothionein-I+II in neuroprotection

    DEFF Research Database (Denmark)

    Pedersen, Mie Ø; Jensen, Rikke; Pedersen, Dan S

    2009-01-01

    -I+II decrease inflammation and secondary tissue damage (oxidative stress, neurodegeneration, and apoptosis) and promote post-injury repair and regeneration (angiogenesis, neurogenesis, neuronal sprouting and tissue remodelling). Intracellularly the molecular MT-I+II actions involve metal ion control...... encephalomyelitis. (c) 2009 International Union of Biochemistry and Molecular Biology, Inc....

  15. Repair kinetics of DNA double-strand breaks and incidence of apoptosis in mouse neural stem/progenitor cells and their differentiated neurons exposed to ionizing radiation.

    Science.gov (United States)

    Kashiwagi, Hiroki; Shiraishi, Kazunori; Sakaguchi, Kenta; Nakahama, Tomoya; Kodama, Seiji

    2018-05-01

    Neuronal loss leads to neurodegenerative disorders, including Alzheimer's disease, Parkinson's disease and Huntington's disease. Because of their long lifespans, neurons are assumed to possess highly efficient DNA repair ability and to be able to protect themselves from deleterious DNA damage such as DNA double-strand breaks (DSBs) produced by intrinsic and extrinsic sources. However, it remains largely unknown whether the DSB repair ability of neurons is more efficient compared with that of other cells. Here, we investigated the repair kinetics of X-ray-induced DSBs in mouse neural cells by scoring the number of phosphorylated 53BP1 foci post irradiation. We found that p53-independent apoptosis was induced time dependently during differentiation from neural stem/progenitor cells (NSPCs) into neurons in culture for 48 h. DSB repair in neurons differentiated from NSPCs in culture was faster than that in mouse embryonic fibroblasts (MEFs), possibly due to the higher DNA-dependent protein kinase activity, but it was similar to that in NSPCs. Further, the incidence of p53-dependent apoptosis induced by X-irradiation in neurons was significantly higher than that in NSPCs. This difference in response of X-ray-induced apoptosis between neurons and NSPCs may reflect a difference in the fidelity of non-homologous end joining or a differential sensitivity to DNA damage other than DSBs.

  16. Safrole oxide induces neuronal apoptosis through inhibition of integrin beta4/SOD activity and elevation of ROS/NADPH oxidase activity.

    Science.gov (United States)

    Su, Le; Zhao, BaoXiang; Lv, Xin; Wang, Nan; Zhao, Jing; Zhang, ShangLi; Miao, JunYing

    2007-02-20

    Neuronal apoptosis is a very important event in the development of the central nervous system (CNS), but the underlying mechanisms remain to be elucidated. We have previously shown that safrole oxide, a small molecule, induces integrin beta4 expression and promotes apoptosis in vascular endothelial cells. In this study, the effects of safrole oxide on cell growth and apoptosis have been examined in primary cultures of mouse neurons. Safrole oxide was found to significantly inhibit neuronal cell growth and to induce apoptosis. The inhibitory and apoptotic activities of safrole oxide followed a dose- and time-dependent manner. Interestingly, the expression of integrin beta4 was significantly inhibited with safrole oxide treatment. Furthermore, safrole oxide dramatically increases the level of intracellular reactive oxygen species (ROS) and the activity of NADPH oxidase. Moreover, manganese-dependent superoxide dismutase (MnSOD) activity was decreased significantly with safrole oxide treatment. Our study thus demonstrates that safrole oxide induces neuronal apoptosis through integrin beta4, ROS, NADPH, and MnSOD.

  17. Indirubin-3-Oxime Prevents H2O2-Induced Neuronal Apoptosis via Concurrently Inhibiting GSK3β and the ERK Pathway.

    Science.gov (United States)

    Yu, Jie; Zheng, Jiacheng; Lin, Jiajia; Jin, Linlu; Yu, Rui; Mak, Shinghung; Hu, Shengquan; Sun, Hongya; Wu, Xiang; Zhang, Zaijun; Lee, Mingyuen; Tsim, Wahkeung; Su, Wei; Zhou, Wenhua; Cui, Wei; Han, Yifan; Wang, Qinwen

    2017-05-01

    Oxidative stress-induced neuronal apoptosis plays an important role in many neurodegenerative disorders. In this study, we have shown that indirubin-3-oxime, a derivative of indirubin originally designed for leukemia therapy, could prevent hydrogen peroxide (H 2 O 2 )-induced apoptosis in both SH-SY5Y cells and primary cerebellar granule neurons. H 2 O 2 exposure led to the increased activities of glycogen synthase kinase 3β (GSK3β) and extracellular signal-regulated kinase (ERK) in SH-SY5Y cells. Indirubin-3-oxime treatment significantly reversed the altered activity of both the PI3-K/Akt/GSK3β cascade and the ERK pathway induced by H 2 O 2 . In addition, both GSK3β and mitogen-activated protein kinase inhibitors significantly prevented H 2 O 2 -induced neuronal apoptosis. Moreover, specific inhibitors of the phosphoinositide 3-kinase (PI3-K) abolished the neuroprotective effects of indirubin-3-oxime against H 2 O 2 -induced neuronal apoptosis. These results strongly suggest that indirubin-3-oxime prevents H 2 O 2 -induced apoptosis via concurrent inhibiting GSK3β and the ERK pathway in SH-SY5Y cells, providing support for the use of indirubin-3-oxime to treat neurodegenerative disorders caused or exacerbated by oxidative stress.

  18. Exosomes from dental pulp stem cells rescue human dopaminergic neurons from 6-hydroxy-dopamine-induced apoptosis.

    Science.gov (United States)

    Jarmalavičiūtė, Akvilė; Tunaitis, Virginijus; Pivoraitė, Ugnė; Venalis, Algirdas; Pivoriūnas, Augustas

    2015-07-01

    Stem cells derived from the dental pulp of human exfoliated deciduous teeth (SHEDs) have unique neurogenic properties that could be potentially exploited for therapeutic use. The importance of paracrine SHED signaling for neuro-regeneration has been recognized, but the exact mechanisms behind these effects are presently unknown. In the present study, we investigated the neuro-protective potential of exosomes and micro-vesicles derived from SHEDs on human dopaminergic neurons during oxidative stress-induced by 6-hydroxy-dopamine (6-OHDA). ReNcell VM human neural stem cells were differentiated into dopaminergic neurons and treated with 100 μmol/L of 6-OHDA alone or in combination with exosomes or micro-vesicles purified by ultracentrifugation from SHEDs cultivated in serum-free medium under two conditions: in standard two-dimensional culture flasks or on laminin-coated micro-carriers in a bioreactor. Real-time monitoring of apoptosis was performed with the use of time-lapse confocal microscopy and the CellEvent Caspase-3/7 green detection reagent. Exosomes but not micro-vesicles derived from SHEDs grown on the laminin-coated three-dimensional alginate micro-carriers suppressed 6-OHDA-induced apoptosis in dopaminergic neurons by approximately 80% throughout the culture period. Strikingly, no such effects were observed for the exosomes derived from SHEDs grown under standard culture conditions. Our results suggest that exosomes derived from SHEDs are considered as new potential therapeutic tool in the treatment of Parkinson's disease. Copyright © 2015 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

  19. Ablation of cholesterol biosynthesis in neural stem cells increases their VEGF expression and angiogenesis but causes neuron apoptosis.

    Science.gov (United States)

    Saito, Kanako; Dubreuil, Veronique; Arai, Yoko; Wilsch-Bräuninger, Michaela; Schwudke, Dominik; Saher, Gesine; Miyata, Takaki; Breier, Georg; Thiele, Christoph; Shevchenko, Andrej; Nave, Klaus-Armin; Huttner, Wieland B

    2009-05-19

    Although sufficient cholesterol supply is known to be crucial for neurons in the developing mammalian brain, the cholesterol requirement of neural stem and progenitor cells in the embryonic central nervous system has not been addressed. Here we have conditionally ablated the activity of squalene synthase (SQS), a key enzyme for endogenous cholesterol production, in the neural stem and progenitor cells of the ventricular zone (VZ) of the embryonic mouse brain. Mutant embryos exhibited a reduced brain size due to the atrophy of the neuronal layers, and died at birth. Analyses of the E11.5-E15.5 dorsal telencephalon and diencephalon revealed that this atrophy was due to massive apoptosis of newborn neurons, implying that this progeny of the SQS-ablated neural stem and progenitor cells was dependent on endogenous cholesterol biosynthesis for survival. Interestingly, the neural stem and progenitor cells of the VZ, the primary target of SQS inactivation, did not undergo significant apoptosis. Instead, vascular endothelial growth factor (VEGF) expression in these cells was strongly upregulated via a hypoxia-inducible factor-1-independent pathway, and angiogenesis in the VZ was increased. Consistent with an increased supply of lipoproteins to these cells, the level of lipid droplets containing triacylglycerides with unsaturated fatty acyl chains was found to be elevated. Our study establishes a direct link between intracellular cholesterol levels, VEGF expression, and angiogenesis. Moreover, our data reveal a hitherto unknown compensatory process by which the neural stem and progenitor cells of the developing mammalian brain evade the detrimental consequences of impaired endogenous cholesterol biosynthesis.

  20. Aging Enables Ca2+ Overload and Apoptosis Induced by Amyloid-β Oligomers in Rat Hippocampal Neurons: Neuroprotection by Non-Steroidal Anti-Inflammatory Drugs and R-Flurbiprofen in Aging Neurons.

    Science.gov (United States)

    Calvo-Rodríguez, María; García-Durillo, Mónica; Villalobos, Carlos; Núñez, Lucía

    2016-07-22

    The most important risk factor for Alzheimer's disease (AD) is aging. Neurotoxicity in AD has been linked to dyshomeostasis of intracellular Ca2+ induced by small aggregates of the amyloid-β peptide 1-42 (Aβ42 oligomers). However, how aging influences susceptibility to neurotoxicity induced by Aβ42 oligomers is unknown. In this study, we used long-term cultures of rat hippocampal neurons, a model of neuronal in vitro aging, to investigate the contribution of aging to Ca2+ dishomeostasis and neuron cell death induced by Aβ42 oligomers. In addition, we tested whether non-steroidal anti-inflammatory drugs (NSAIDs) and R-flurbiprofen prevent apoptosis acting on subcellular Ca2+ in aged neurons. We found that Aβ42 oligomers have no effect on young hippocampal neurons cultured for 2 days in vitro (2 DIV). However, they promoted apoptosis modestly in mature neurons (8 DIV) and these effects increased dramatically after 13 DIV, when neurons display many hallmarks of in vivo aging. Consistently, cytosolic and mitochondrial Ca2+ responses induced by Aβ42 oligomers increased dramatically with culture age. At low concentrations, NSAIDs and the enantiomer R-flurbiprofen lacking anti-inflammatory activity prevent Ca2+ overload and neuron cell death induced by Aβ42 oligomers in aged neurons. However, at high concentrations R-flurbiprofen induces apoptosis. Thus, Aβ42 oligomers promote Ca2+ overload and neuron cell death only in aged rat hippocampal neurons. These effects are prevented by low concentrations of NSAIDs and R-flurbiprofen acting on mitochondrial Ca2+ overload.

  1. Involvement of the JNK/FOXO3a/Bim Pathway in Neuronal Apoptosis after Hypoxic-Ischemic Brain Damage in Neonatal Rats.

    Directory of Open Access Journals (Sweden)

    Deyuan Li

    Full Text Available c-Jun N-terminal kinase (JNK plays a key role in the regulation of neuronal apoptosis. Previous studies have revealed that forkhead transcription factor (FOXO3a is a critical effector of JNK-mediated tumor suppression. However, it is not clear whether the JNK/FOXO3a pathway is involved in neuronal apoptosis in the developing rat brain after hypoxia-ischemia (HI. In this study, we generated an HI model using postnatal day 7 rats. Fluorescence immunolabeling and Western blot assays were used to detect the distribution and expression of total and phosphorylated JNK and FOXO3a and the pro-apoptotic proteins Bim and CC3. We found that JNK phosphorylation was accompanied by FOXO3a dephosphorylation, which induced FOXO3a translocation into the nucleus, resulting in the upregulation of levels of Bim and CC3 proteins. Furthermore, we found that JNK inhibition by AS601245, a specific JNK inhibitor, significantly increased FOXO3a phosphorylation, which attenuated FOXO3a translocation into the nucleus after HI. Moreover, JNK inhibition downregulated levels of Bim and CC3 proteins, attenuated neuronal apoptosis and reduced brain infarct volume in the developing rat brain. Our findings suggest that the JNK/FOXO3a/Bim pathway is involved in neuronal apoptosis in the developing rat brain after HI. Agents targeting JNK may offer promise for rescuing neurons from HI-induced damage.

  2. Metallothionein expression in the central nervous system of multiple sclerosis patients

    DEFF Research Database (Denmark)

    Penkowa, M; Espejo, C; Ortega-Aznar, A

    2003-01-01

    Multiple sclerosis (MS) is a major chronic demyelinating and inflammatory disease of the central nervous system (CNS) in which oxidative stress likely plays a pathogenic role in the development of myelin and neuronal damage. Metallothioneins (MTs) are antioxidant proteins induced in the CNS...

  3. [Protective effect of pretreatment of Salvia miltiorrhiza Bunge. f. alba plasma against oxygen-glucose deprivation-induced injury of cultured rat hippocampal neurons by inhibiting apoptosis].

    Science.gov (United States)

    Li, Mei-Yi; Zhang, Yan-Bo; Zuo, Huan; Liu, Li-Li; Niu, Jing-Zhong

    2012-02-25

    The present study was to investigate the effect of Salvia miltiorrhiza Bunge. f. alba (SMA) pharmacological pretreatment on apoptosis of cultured hippocampal neurons from neonate rats under oxygen-glucose deprivation (OGD). Cultured hippocampal neurons were randomly divided into five groups (n = 6): normal plasma group, low dose SMA plasma (2.5%) group, middle dose SMA plasma (5%) group, high dose SMA plasma (10%) group and control group. The hippocampal neurons were cultured and treated with plasma from adult Wistar rats intragastrically administered with saline or aqueous extract of SMA. The apoptosis of neurons was induced by glucose-free Earle's solution containing 1 mmol/L Na2S2O4 and labeled by MTT and Annexin V/PI double staining. Moreover, protein expressions of Bcl-2 and Bax were detected by immunofluorescence. The results showed that few apoptotic cells were observed in control group, whereas the number of apoptotic cells was greatly increased in normal plasma group and low dose SMA plasma group. Both middle and high dose SMA plasma could protect cultured hippocampal neurons from apoptosis induced by OGD (P control, normal plasma and low dose SMA plasma groups, middle and high dose SMA plasma groups both showed significantly higher levels of Bcl-2 (P neurons by up-regulating the expression of Bcl-2 and down-regulating the expression of Bax.

  4. cAMP/PKA signaling pathway contributes to neuronal apoptosis via regulating IDE expression in a mixed model of type 2 diabetes and Alzheimer's disease.

    Science.gov (United States)

    Li, Huajie; Yang, Song; Wu, Jian; Ji, Lei; Zhu, Linfeng; Cao, Liping; Huang, Jinzhong; Jiang, Qingqing; Wei, Jiang; Liu, Meng; Mao, Keshi; Wei, Ning; Xie, Wei; Yang, Zhilong

    2018-02-01

    Type 2 diabetes (T2D) may play a relevant role in the development of Alzheimer's disease (AD), however, the underlying mechanism was not clear yet. We developed an animal model presenting both AD and T2D, morris water maze (MWM) test and recognition task were performed to trace the cognitive function. Fasting plasma glucose (FPG) and oral glucose tolerance test (OGTT) were determined to trace the metabolism evolution. TUNEL assay and apoptosis-related protein levels were analyzed for the detection of neuronal apoptosis. Cyclic adenosine monophosphate (cAMP) agonist bucladesine or protein kinase (PKA) inhibitor H-89 were used to determine the effects of cAMP/PKA signaling pathway on IDE expression and neuronal apoptosis. The results showed that T2D contributes to the AD progress by accelerating and worsening spatial memory and recognition dysfunctions. Metabolic parameters and glucose tolerance were significantly changed in the presence of the AD and T2D. The significantly induced neuronal apoptosis and increased pro-apoptotic proteins in mice with AD and T2D were also observed. We showed the decreased expression level of IDE and the activating of cAMP/PKA signaling pathway in AD and T2D mice. Further studies indicated that cAMP agonist decreased the expression level of IDE and induced the neuronal apoptosis in mice with AD and T2D; whereas PKA inhibitor H-89 treatment showed the completely opposite results. Our study indicated that, in the T2D and AD mice, cAMP/PKA signaling pathway and IDE may participate in the contribute role of T2D in accelerating the pathological process of AD via causing the accumulation of Aβ and neuronal apoptosis. © 2017 Wiley Periodicals, Inc.

  5. Metallothionein as an Anti-Inflammatory Mediator

    Directory of Open Access Journals (Sweden)

    Ken-ichiro Inoue

    2009-01-01

    Full Text Available The integration of knowledge concerning the regulation of MT, a highly conserved, low molecular weight, cystein-rich metalloprotein, on its proposed functions is necessary to clarify how MT affects cellular processes. MT expression is induced/enhanced in various tissues by a number of physiological mediators. The cellular accumulation of MT depends on the availability of cellular zinc derived from the diet. MT modulates the binding and exchange/transport of heavy metals such as zinc, cadmium, or copper under physiological conditions and cytoprotection from their toxicities, and the release of gaseous mediators such as hydroxyl radicals or nitric oxide. In addition, MT reportedly affects a number of cellular processes, such as gene expression, apoptosis, proliferation, and differentiation. Given the genetic approach, the apparently healthy status of MT-deficient mice argues against an essential biological role for MT; however, this molecule may be critical in cells/tissues/organs in times of stress, since MT expression is also evoked/enhanced by various stresses. In particular, because metallothionein (MT is induced by inflammatory stress, its roles in inflammation are implied. Also, MT expression in various organs/tissues can be enhanced by inflammatory stimuli, implicating in inflammatory diseases. In this paper, we review the role of MT of various inflammatory conditions.

  6. Arsenic trioxide mediates HAPI microglia inflammatory response and subsequent neuron apoptosis through p38/JNK MAPK/STAT3 pathway

    Energy Technology Data Exchange (ETDEWEB)

    Mao, Jiamin [Department of Environmental Health, School of Public Health, Nantong University, Nantong, Jiangsu 226001 (China); Yang, Jianbing [Department of Pediatrics, Affiliated Hospital of Nantong University, Nantong, Jiangsu 226001 (China); Zhang, Yan [Department of Nutrition and Food Hygiene, School of Public Health, Nantong University, Nantong, Jiangsu 226001 (China); Li, Ting [Department of Environmental Health, School of Public Health, Nantong University, Nantong, Jiangsu 226001 (China); Wang, Cheng [Department of Nutrition and Food Hygiene, School of Public Health, Nantong University, Nantong, Jiangsu 226001 (China); Xu, Lingfei; Hu, Qiaoyun; Wang, Xiaoke; Jiang, Shengyang [Department of Environmental Health, School of Public Health, Nantong University, Nantong, Jiangsu 226001 (China); Nie, Xiaoke [Department of Nutrition and Food Hygiene, School of Public Health, Nantong University, Nantong, Jiangsu 226001 (China); Chen, Gang, E-mail: chengang@ntu.edu.cn [Department of Environmental Health, School of Public Health, Nantong University, Nantong, Jiangsu 226001 (China)

    2016-07-15

    Arsenic is a widely distributed toxic metalloid all over the world. Inorganic arsenic species are supposed to affect astrocytic functions and to cause neuron apoptosis in CNS. Microglias are the key cell type involved in innate immune responses in CNS, and microglia activation has been linked to inflammation and neurotoxicity. In this study, using ELISA, we showed that Arsenic trioxide up-regulated the expression and secretion of IL-1β in a dose-dependent manner and a time-dependent manner in cultured HAPI microglia cells. The secretion of IL-1β caused the apoptosis of SH-SY5Y. These pro-inflammatory responses were inhibited by the STAT3 blocker, AG490 and P38/JNK MAPK blockers SB202190, SP600125. Further, Arsenic trioxide exposure could induce phosphorylation and activation of STAT3, and the translocation of STAT3 from the cytosol to the nucleus in this HAPI microglia cell line. Thus, the STAT3 signaling pathway can be activated after Arsenic trioxide treatment. However, P38/JNK MAPK blockers SB202190, SP600125 also obviously attenuated STAT3 activation and transnuclear transport induced by Arsenic trioxide. In concert with these results, we highlighted that the secretion of IL-1β and STAT3 activation induced by Arsenic trioxide can be mediated by elevation of P38/JNK MAPK in HAPI microglia cells and then induced the toxicity of neurons. - Highlights: • Arsenic trioxide exposure induced expression of IL-β in HAPI microglia. • Arsenic trioxide exposure induced activation of MAPK pathways in HAPI microglia. • Arsenic trioxide exposure induced activation of STAT3 pathways in HAPI microglia. • The expression of IL-β though P38/JNK MAPK/STAT3 pathways in HAPI microglia.

  7. Arsenic trioxide mediates HAPI microglia inflammatory response and subsequent neuron apoptosis through p38/JNK MAPK/STAT3 pathway

    International Nuclear Information System (INIS)

    Mao, Jiamin; Yang, Jianbing; Zhang, Yan; Li, Ting; Wang, Cheng; Xu, Lingfei; Hu, Qiaoyun; Wang, Xiaoke; Jiang, Shengyang; Nie, Xiaoke; Chen, Gang

    2016-01-01

    Arsenic is a widely distributed toxic metalloid all over the world. Inorganic arsenic species are supposed to affect astrocytic functions and to cause neuron apoptosis in CNS. Microglias are the key cell type involved in innate immune responses in CNS, and microglia activation has been linked to inflammation and neurotoxicity. In this study, using ELISA, we showed that Arsenic trioxide up-regulated the expression and secretion of IL-1β in a dose-dependent manner and a time-dependent manner in cultured HAPI microglia cells. The secretion of IL-1β caused the apoptosis of SH-SY5Y. These pro-inflammatory responses were inhibited by the STAT3 blocker, AG490 and P38/JNK MAPK blockers SB202190, SP600125. Further, Arsenic trioxide exposure could induce phosphorylation and activation of STAT3, and the translocation of STAT3 from the cytosol to the nucleus in this HAPI microglia cell line. Thus, the STAT3 signaling pathway can be activated after Arsenic trioxide treatment. However, P38/JNK MAPK blockers SB202190, SP600125 also obviously attenuated STAT3 activation and transnuclear transport induced by Arsenic trioxide. In concert with these results, we highlighted that the secretion of IL-1β and STAT3 activation induced by Arsenic trioxide can be mediated by elevation of P38/JNK MAPK in HAPI microglia cells and then induced the toxicity of neurons. - Highlights: • Arsenic trioxide exposure induced expression of IL-β in HAPI microglia. • Arsenic trioxide exposure induced activation of MAPK pathways in HAPI microglia. • Arsenic trioxide exposure induced activation of STAT3 pathways in HAPI microglia. • The expression of IL-β though P38/JNK MAPK/STAT3 pathways in HAPI microglia.

  8. Inhibitor of apoptosis-stimulating protein of p53 (iASPP is required for neuronal survival after axonal injury.

    Directory of Open Access Journals (Sweden)

    Ariel M Wilson

    Full Text Available The transcription factor p53 mediates the apoptosis of post-mitotic neurons exposed to a wide range of stress stimuli. The apoptotic activity of p53 is tightly regulated by the apoptosis-stimulating proteins of p53 (ASPP family members: ASPP1, ASPP2 and iASPP. We previously showed that the pro-apoptotic members ASPP1 and ASPP2 contribute to p53-dependent death of retinal ganglion cells (RGCs. However, the role of the p53 inhibitor iASPP in the central nervous system (CNS remains to be elucidated. To address this, we asked whether iASPP contributes to the survival of RGCs in an in vivo model of acute optic nerve damage. We demonstrate that iASPP is expressed by injured RGCs and that iASPP phosphorylation at serine residues, which increase iASPP affinity towards p53, is significantly reduced following axotomy. We show that short interference RNA (siRNA-induced iASPP knockdown exacerbates RGC death, whereas adeno-associated virus (AAV-mediated iASPP expression promotes RGC survival. Importantly, our data also demonstrate that increasing iASPP expression in RGCs downregulates p53 activity and blocks the expression of pro-apoptotic targets PUMA and Fas/CD95. This study demonstrates a novel role for iASPP in the survival of RGCs, and provides further evidence of the importance of the ASPP family in the regulation of neuronal loss after axonal injury.

  9. Nrdp1 Increases Ischemia Induced Primary Rat Cerebral Cortical Neurons and Pheochromocytoma Cells Apoptosis Via Downregulation of HIF-1α Protein

    Directory of Open Access Journals (Sweden)

    Yuan Zhang

    2017-09-01

    Full Text Available Neuregulin receptor degradation protein-1 (Nrdp1 is an E3 ubiquitin ligase that targets proteins for degradation and regulates cell growth, apoptosis and oxidative stress in various cell types. We have previously shown that Nrdp1 is implicated in ischemic cardiomyocyte death. In this study, we investigated the change of Nrdp1 expression in ischemic neurons and its role in ischemic neuronal injury. Primary rat cerebral cortical neurons and pheochromocytoma (PC12 cells were infected with adenoviral constructs expressing Nrdp1 gene or its siRNA before exposing to oxygen-glucose deprivation (OGD treatment. Our data showed that Nrdp1 was upregulated in ischemic brain tissue 3 h after middle cerebral artery occlusion (MCAO and in OGD-treated neurons. Of note, Nrdp1 overexpression by Ad-Nrdp1 enhanced OGD-induced neuron apoptosis, while knockdown of Nrdp1 with siRNA attenuated this effect, implicating a role of Nrdp1 in ischemic neuron injury. Moreover, Nrdp1 upregulation is accompanied by increased protein ubiquitylation and decreased protein levels of ubiquitin-specific protease 8 (USP8 in OGD-treated neurons, which led to a suppressed interaction between USP8 and HIF-1α and subsequently a reduction in HIF-1α protein accumulation in neurons under OGD conditions. In conclusion, our data support an important role of Nrdp1 upregulation in ischemic neuronal death, and suppressing the interaction between USP8 and HIF-1α and consequently the hypoxic adaptive response of neurons may account for this detrimental effect.

  10. Survival effect of PDGF-CC rescues neurons from apoptosis in both brain and retina by regulating GSK3β phosphorylation

    Science.gov (United States)

    Tang, Zhongshu; Arjunan, Pachiappan; Lee, Chunsik; Li, Yang; Kumar, Anil; Hou, Xu; Wang, Bin; Wardega, Piotr; Zhang, Fan; Dong, Lijin; Zhang, Yongqing; Zhang, Shi-Zhuang; Ding, Hao; Fariss, Robert N.; Becker, Kevin G.; Lennartsson, Johan; Nagai, Nobuo; Cao, Yihai

    2010-01-01

    Platelet-derived growth factor CC (PDGF-CC) is the third member of the PDGF family discovered after more than two decades of studies on the original members of the family, PDGF-AA and PDGF-BB. The biological function of PDGF-CC remains largely to be explored. We report a novel finding that PDGF-CC is a potent neuroprotective factor that acts by modulating glycogen synthase kinase 3β (GSK3β) activity. In several different animal models of neuronal injury, such as axotomy-induced neuronal death, neurotoxin-induced neuronal injury, 6-hydroxydopamine–induced Parkinson’s dopaminergic neuronal death, and ischemia-induced stroke, PDGF-CC protein or gene delivery protected different types of neurons from apoptosis in both the retina and brain. On the other hand, loss-of-function assays using PDGF-C null mice, neutralizing antibody, or short hairpin RNA showed that PDGF-CC deficiency/inhibition exacerbated neuronal death in different neuronal tissues in vivo. Mechanistically, we revealed that the neuroprotective effect of PDGF-CC was achieved by regulating GSK3β phosphorylation and expression. Our data demonstrate that PDGF-CC is critically required for neuronal survival and may potentially be used to treat neurodegenerative diseases. Inhibition of the PDGF-CC–PDGF receptor pathway for different clinical purposes should be conducted with caution to preserve normal neuronal functions. PMID:20231377

  11. Metallothionein-I plus II and receptor megalin are altered in relation to oxidative stress in cerebral lymphomas

    DEFF Research Database (Denmark)

    Pedersen, M.O.; Hansen, P.B.; Nielsen, Signe Ledou

    2010-01-01

    . This article characterizes the histopathology and expression profiles of metallothionein-I + II (MT-I + II) and their receptor megalin along with proliferation, oxidative stress, and apoptosis in PCNSL and in central nervous system (CNS) lymphomas due to relapse from DLBCL (collectively referred to as CNS...

  12. Folate deprivation induces cell cycle arrest at G0/G1 phase and apoptosis in hippocampal neuron cells through down-regulation of IGF-1 signaling pathway.

    Science.gov (United States)

    Yang, Yang; Li, Xi; Sun, Qinwei; He, Bin; Jia, Yimin; Cai, Demin; Zhao, Ruqian

    2016-10-01

    Folate deficiency contributes to impaired adult hippocampal neurogenesis, yet the mechanisms remain unclear. Here we use HT-22 hippocampal neuron cells as model to investigate the effect of folate deprivation (FD) on cell proliferation and apoptosis, and to elucidate the underlying mechanism. FD caused cell cycle arrest at G0/G1 phase and increased the rate of apoptosis, which was associated with disrupted expression of folate transport and methyl transfer genes. FOLR1 and SLC46A1 were (Pmethyl transfer pathway and hypermethylation of IGF-1 gene promoter. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Osthole promotes neuronal differentiation and inhibits apoptosis via Wnt/β-catenin signaling in an Alzheimer's disease model

    Energy Technology Data Exchange (ETDEWEB)

    Yao, Yingjia [School of Pharmacy, Liaoning University of Traditional Chinese Medicine, Dalian 116600 (China); Gao, Zhong [Department of Interventional Therapy, Dalian Municipal Central Hospital, Dalian 116033 (China); Liang, Wenbo [Medical College of Dalian University, Dalian 116600, Liaoning (China); Kong, Liang; Jiao, Yanan; Li, Shaoheng; Tao, Zhenyu; Yan, Yuhui [School of Pharmacy, Liaoning University of Traditional Chinese Medicine, Dalian 116600 (China); Yang, Jingxian, E-mail: jingxianyang@yahoo.com [School of Pharmacy, Liaoning University of Traditional Chinese Medicine, Dalian 116600 (China)

    2015-12-15

    Neurogenesis is the process by which neural stem cells (NSCs) proliferate and differentiate into neurons. This is diminished in several neurodegenerative disorders such as Alzheimer's disease (AD), which is characterized by the deposition of amyloid (A)β peptides and neuronal loss. Stimulating NSCs to replace lost neurons is therefore a promising approach for AD treatment. Our previous study demonstrated that osthole modulates NSC proliferation and differentiation, and may reduce Aβ protein expression in nerve cells. Here we investigated the mechanism underlying the effects of osthole on NSCs. We found that osthole enhances NSC proliferation and neuronal differentiation while suppressing apoptosis, effects that were exerted via activation of Wnt/β-catenin signaling. These results provide evidence that osthole can potentially be used as a therapeutic agent in the treatment of AD and other neurodegenerative disorders. - Highlights: • An Alzheimer's disease model was successfully established by transfecting APP gene into neural stem cells in vitro. • Roles of osthole in experimental AD cells were studied. • Osthole promotes proliferation and differentiation into neurons and inhibits accumulation of Aβ{sub 1–42} peptide and apoptosis. • Osthole exerts protection via Wnt/β-catenin signaling pathway.

  14. Fucoxanthin prevents H2O2-induced neuronal apoptosis via concurrently activating the PI3-K/Akt cascade and inhibiting the ERK pathway.

    Science.gov (United States)

    Yu, Jie; Lin, Jia-Jia; Yu, Rui; He, Shan; Wang, Qin-Wen; Cui, Wei; Zhang, Jin-Rong

    2017-01-01

    Background : As a natural carotenoid abundant in chloroplasts of edible brown algae, fucoxanthin possesses various health benefits, including anti-oxidative activity in particular. Objective : In the present study, we studied whether fucoxanthin protected against hydrogen peroxide (H 2 O 2 )-induced neuronal apoptosis. Design : The neuroprotective effects of fucoxanthin on H 2 O 2 -induced toxicity were studied in both SH-SY5Y cells and primary cerebellar granule neurons. Results : Fucoxanthin significantly protected against H 2 O 2 -induced neuronal apoptosis and intracellular reactive oxygen species. H 2 O 2 treatment led to the reduced activity of phosphoinositide 3-kinase (PI3-K)/Akt cascade and the increased activity of extracellular signal-regulated kinase (ERK) pathway in SH-SY5Y cells. Moreover, fucoxanthin significantly restored the altered activities of PI3-K/Akt and ERK pathways induced by H 2 O 2 . Both specific inhibitors of glycogen synthase kinase 3β (GSK3β) and mitogen-activated protein kinase kinase (MEK) significantly protected against H 2 O 2 -induced neuronal death. Furthermore, the neuroprotective effects of fucoxanthin against H 2 O 2 -induced neuronal death were abolished by specific PI3-K inhibitors. Conclusions : Our data strongly revealed that fucoxanthin protected against H 2 O 2 -induced neurotoxicity via concurrently activating the PI3-K/Akt cascade and inhibiting the ERK pathway, providing support for the use of fucoxanthin to treat neurodegenerative disorders induced by oxidative stress.

  15. Osthole promotes neuronal differentiation and inhibits apoptosis via Wnt/β-catenin signaling in an Alzheimer's disease model

    International Nuclear Information System (INIS)

    Yao, Yingjia; Gao, Zhong; Liang, Wenbo; Kong, Liang; Jiao, Yanan; Li, Shaoheng; Tao, Zhenyu; Yan, Yuhui; Yang, Jingxian

    2015-01-01

    Neurogenesis is the process by which neural stem cells (NSCs) proliferate and differentiate into neurons. This is diminished in several neurodegenerative disorders such as Alzheimer's disease (AD), which is characterized by the deposition of amyloid (A)β peptides and neuronal loss. Stimulating NSCs to replace lost neurons is therefore a promising approach for AD treatment. Our previous study demonstrated that osthole modulates NSC proliferation and differentiation, and may reduce Aβ protein expression in nerve cells. Here we investigated the mechanism underlying the effects of osthole on NSCs. We found that osthole enhances NSC proliferation and neuronal differentiation while suppressing apoptosis, effects that were exerted via activation of Wnt/β-catenin signaling. These results provide evidence that osthole can potentially be used as a therapeutic agent in the treatment of AD and other neurodegenerative disorders. - Highlights: • An Alzheimer's disease model was successfully established by transfecting APP gene into neural stem cells in vitro. • Roles of osthole in experimental AD cells were studied. • Osthole promotes proliferation and differentiation into neurons and inhibits accumulation of Aβ 1–42 peptide and apoptosis. • Osthole exerts protection via Wnt/β-catenin signaling pathway.

  16. [TRPM8 mediates PC-12 neuronal cell apoptosis induced by oxygen-glucose deprivation through cAMP-PKA/UCP4 signaling].

    Science.gov (United States)

    Li, Hong-Wei; Zhou, Bin; Zhang, Hai-Hong

    2016-08-20

    To explore the molecular mechanism responsible for apoptosis of PC-12 neuronal cells induced by oxygen-glucose deprivation (OGD). PC12 cells were exposed to OGD for 24 h to simulate ischemia-reperfusion injury. Flow cytometry was employed detect the cell apoptosis, and the expresions of TRPM8, UCP4, cAMP and PKA in the exposed cells were detected with RT-PCR and Western blotting. The changes in the expressions of Bax, Bcl-2, cAMP, PKA and UCP4 proteins were detected in the exposed cells in resposne to inhibition of TRPM8 and cAMP-PKA signal or over-expression of UCP4. OGD for 24 induced obvious apoptosis in PC-12 cells and caused TRPM8 over-expression and inhibition of UCP4 and cAMP-PKA signaling. Inhibiting TRPM8 expression reduced the cell apoptosis and up-regulated cAMP, p-PKA and UCP4 in the cells exposed to OGD. In cells exposed to OGD, inhibition of TRPM8 and cAMP-PKA signaling suppressed the expressio of UCP4 and increased the cell apoptosis. TRPM8 mediates OGD-induced PC12 cell apoptosis through cAMP-PKA/UCP4 signaling.

  17. Glutamate-induced apoptosis in neuronal cells is mediated via caspase-dependent and independent mechanisms involving calpain and caspase-3 proteases as well as apoptosis inducing factor (AIF and this process is inhibited by equine estrogens

    Directory of Open Access Journals (Sweden)

    Bhavnani Bhagu R

    2006-06-01

    Full Text Available Abstract Background Glutamate, a major excitatory amino acid neurotransmitter, causes apoptotic neuronal cell death at high concentrations. Our previous studies have shown that depending on the neuronal cell type, glutamate-induced apoptotic cell death was associated with regulation of genes such as Bcl-2, Bax, and/or caspase-3 and mitochondrial cytochrome c. To further delineate the intracellular mechanisms, we have investigated the role of calpain, an important calcium-dependent protease thought to be involved in apoptosis along with mitochondrial apoptosis inducing factor (AIF and caspase-3 in primary cortical cells and a mouse hippocampal cell line HT22. Results Glutamate-induced apoptotic cell death in neuronal cells was associated with characteristic DNA fragmentation, morphological changes, activation of calpain and caspase-3 as well as the upregulation and/or translocation of AIF from mitochondria into cytosol and nuclei. Our results reveal that primary cortical cells and HT22 cells display different patterns of regulation of these genes/proteins. In primary cortical cells, glutamate induces activation of calpain, caspase-3 and translocation of AIF from mitochondria to cytosol and nuclei. In contrast, in HT22 cells, only the activation of calpain and upregulation and translocation of AIF occurred. In both cell types, these processes were inhibited/reversed by 17β-estradiol and Δ8,17β-estradiol with the latter being more potent. Conclusion Depending upon the neuronal cell type, at least two mechanisms are involved in glutamate-induced apoptosis: a caspase-3-dependent pathway and a caspase-independent pathway involving calpain and AIF. Since HT22 cells lack caspase-3, glutamate-induced apoptosis is mediated via the caspase-independent pathway in this cell line. Kinetics of this apoptotic pathway further indicate that calpain rather than caspase-3, plays a critical role in the glutamate-induced apoptosis. Our studies further indicate

  18. Metallothionein gene expression in renal cell carcinoma

    Directory of Open Access Journals (Sweden)

    Deeksha Pal

    2014-01-01

    Full Text Available Introduction: Metallothioneins (MTs are a group of low-molecular weight, cysteine-rich proteins. In general, MT is known to modulate three fundamental processes: (1 the release of gaseous mediators such as hydroxyl radical or nitric oxide, (2 apoptosis and (3 the binding and exchange of heavy metals such as zinc, cadmium or copper. Previous studies have shown a positive correlation between the expression of MT with invasion, metastasis and poor prognosis in various cancers. Most of the previous studies primarily used immunohistochemistry to analyze localization of MT in renal cell carcinoma (RCC. No information is available on the gene expression of MT2A isoform in different types and grades of RCC. Materials and Methods: In the present study, total RNA was isolated from 38 histopathologically confirmed cases of RCC of different types and grades. Corresponding adjacent normal renal parenchyma was taken as control. Real-time polymerase chain reaction (RT PCR analysis was done for the MT2A gene expression using b-actin as an internal control. All statistical calculations were performed using SPSS software. Results: The MT2A gene expression was found to be significantly increased (P < 0.01 in clear cell RCC in comparison with the adjacent normal renal parenchyma. The expression of MT2A was two to three-fold higher in sarcomatoid RCC, whereas there was no change in papillary and collecting duct RCC. MT2A gene expression was significantly higher in lower grade (grades I and II, P < 0.05, while no change was observed in high-grade tumor (grade III and IV in comparison to adjacent normal renal tissue. Conclusion: The first report of the expression of MT2A in different types and grades of RCC and also these data further support the role of MT2A in tumorigenesis.

  19. Cytotoxicant-induced trophoblast dysfunction and abnormal pregnancy outcomes: role of zinc and metallothionein.

    Science.gov (United States)

    McAleer, Mary Frances; Tuan, Rocky S

    2004-12-01

    Normal trophoblast function, including implantation, hormone production, and formation of the selectively permeable maternofetal barrier, is essential for the establishment and maintenance of the fetoplacental unit and proper fetal development. Maternal cytotoxicant exposure causes the destruction of these cells, especially the terminally differentiated syncytiotrophoblasts, and results in a myriad of poor pregnancy outcomes. These outcomes range from intrauterine growth retardation and malformation to spontaneous abortion or stillbirth. There is recent evidence that the metal-binding protein, metallothionein, is involved in the protection of human trophoblastic cells from heavy metal-induced and severe oxidative stress-induced apoptosis. Metallothionein, with its unique biochemical structure, can both bind essential metal ions, such as the transcription modulator zinc, and yet allow their ready displacement by toxic nonessential metal ions or damaging free radicals. These properties suggest that metallothionein may be responsible not only for sequestering the cytotoxic agents, but also for altering signal transduction in the affected cells. Here, we review several identified causes of adverse pregnancy outcomes (specifically, prenatal exposure to cigarette smoke and alcohol, gestational infection, and exposure to environmental contaminants), discuss the role of zinc in modulating the cellular response to these toxic insults, and then propose how metallothionein may function to mediate this protective response. Published 2005 Wiley-Liss, Inc.

  20. APOEε4 increases trauma induced early apoptosis via reducing delayed rectifier K(+) currents in neuronal/glial co-cultures model.

    Science.gov (United States)

    Chen, Ligang; Sun, Xiaochuan; Jiang, Yong; Kuai, Li

    2015-06-10

    Traumatic brain injury (TBI) is a commonly encountered emergency and severe neurosurgical injury. Previous studies have shown that the presence of the apolipoprotein E (APOE) ε4 allele has adverse outcomes across the spectrum of TBI severity. Our objective was to evaluate the effects of APOE alleles on trauma induced early apoptosis via modification of delayed rectifier K(+) current (Ik(DR)) in neuronal/glial co-cultures model. An ex vivo neuronal/glial co-cultures model carrying individual APOE alleles (ε2, ε3, ε4) of mechanical injury was developed. Flow cytometry and patch clamp recording were performed to analyze the correlations among APOE genotypes, early apoptosis and Ik(DR). We found that APOEε4 increased early apoptosis at 24h (p<0.05) compared to the ones transfected with APOEε3 and APOEε2. Noticeably, APOEε4 significantly reduced the amplitude of the Ik(DR) at 24h compared to the APOEε3 and APOEε2 (p<0.05) which exacerbate Ca(2+) influx. This indicates a possible effect of APOEε4 on early apoptosis via inhibiting Ik(DR) following injury which may adversely affect the outcome of TBI. Copyright © 2015 Elsevier Inc. All rights reserved.

  1. Metallothionein Isoform Expression in Benign and Malignant Thyroid Lesions.

    Science.gov (United States)

    Wojtczak, Beata; Pula, Bartosz; Gomulkiewicz, Agnieszka; Olbromski, Mateusz; Podhorska-Okolow, Marzena; Domoslawski, Paweł; Bolanowski, Marek; Daroszewski, Jacek; Dziegiel, Piotr

    2017-09-01

    Metallothioneins (MTs) are involved in numerous cell processes such as binding and transport of zinc and copper ions, differentiation, proliferation and apoptosis, therefore contributing to carcinogenesis. Scarce data exist on their expression in benign and malignant lesions of the thyroid. mRNA expression of functional isoforms of MT genes (MT1A, MT1B, MT1E, MT1F, MT1G, MT1H, MT1X, MT2A, MT4) was studied in 17 nodular goiters (NG), 12 follicular adenomas (FA) and 26 papillary thyroid carcinomas (PTC). One-way ANOVA revealed significant differences in mRNA expression levels of MT1A (pbenign and malignant lesions. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

  2. Elevated hydrostatic pressures induce apoptosis and oxidative stress through mitochondrial membrane depolarization in PC12 neuronal cells: A cell culture model of glaucoma.

    Science.gov (United States)

    Tök, Levent; Nazıroğlu, Mustafa; Uğuz, Abdülhadi Cihangir; Tök, Ozlem

    2014-10-01

    Despite the importance of oxidative stress and apoptosis through mitochondrial depolarization in neurodegenerative diseases, their roles in etiology of glaucoma are poorly understood. We aimed to investigate whether oxidative stress and apoptosis formation are altered in rat pheochromocytoma-derived cell line-12 (PC12) neuronal cell cultures exposed to elevated different hydrostatic pressures as a cell culture model of glaucoma. Cultured PC12 cells were subjected to 0, 15 and 70 mmHg hydrostatic pressure for 1 and 24 h. Then, the following values were analyzed: (a) cell viability; (b) lipid peroxidation and intracellular reactive oxygen species production; (c) mitochondrial membrane depolarization; (d) cell apoptosis; (e) caspase-3 and caspase-9 activities; (f) reduced glutathione (GSH) and glutathione peroxidase (GSH-Px). The hydrostatic pressures (15 and 70 mmHg) increased oxidative cell damage through a decrease of GSH and GSH-Px values, and increasing mitochondrial membrane potential. Additionally, 70 mmHg hydrostatic pressure for 24 h indicated highest apoptotic effects, as demonstrated by plate reader analyses of apoptosis, caspase-3 and -9 values. The present data indicated oxidative stress, apoptosis and mitochondrial changes in PC12 cell line during different hydrostatic pressure as a cell culture model of glaucoma. This findings support the view that mitochondrial oxidative injury contributes early to glaucomatous optic neuropathy.

  3. Neuroprotective Effects of Metallothionein Against Rotenone-Induced Myenteric Neurodegeneration in Parkinsonian Mice

    OpenAIRE

    Murakami, Shinki; Miyazaki, Ikuko; Sogawa, Norio; Miyoshi, Ko; Asanuma, Masato

    2014-01-01

    Parkinson's disease (PD) is a neurodegenerative disease with motor symptoms as well as non-motor symptoms that precede the onset of motor symptoms. Mitochondrial complex I inhibitor, rotenone, has been widely used to reproduce PD pathology in the central nervous system (CNS) and enteric nervous system (ENS). We reported previously that metallothioneins (MTs) released from astrocytes can protect dopaminergic neurons against oxidative stress. The present study examined the changes in MT express...

  4. In vitro evidence of glucose-induced toxicity in GnRH secreting neurons: high glucose concentrations influence GnRH secretion, impair cell viability, and induce apoptosis in the GT1-1 neuronal cell line.

    Science.gov (United States)

    Pal, Lubna; Chu, Hsiao-Pai; Shu, Jun; Topalli, Ilir; Santoro, Nanette; Karkanias, George

    2007-10-01

    To evaluate for direct toxic effects of high glucose concentrations on cellular physiology in GnRH secreting immortalized GT1-1 neurons. Prospective experimental design. In vitro experimental model using a cell culture system. GT1-1 cells were cultured in replicates in media with two different glucose concentrations (450 mg/dL and 100 mg/dL, respectively) for varying time intervals (24, 48, and 72 hours). Effects of glucose concentrations on GnRH secretion by the GT1-1 neurons were evaluated using a static culture model. Cell viability, cellular apoptosis, and cell cycle events in GT1-1 neurons maintained in two different glucose concentrations were assessed by flow cytometry (fluorescence-activated cell sorter) using Annexin V-PI staining. Adverse influences of high glucose concentrations on GnRH secretion and cell viability were noted in cultures maintained in high glucose concentration (450 mg/dL) culture medium for varying time intervals. A significantly higher percentage of cells maintained in high glucose concentration medium demonstrated evidence of apoptosis by a fluorescence-activated cell sorter. We provide in vitro evidence of glucose-induced cellular toxicity in GnRH secreting GT1-1 neurons. Significant alterations in GnRH secretion, reduced cell viability, and a higher percentage of apoptotic cells were observed in GT1-1 cells maintained in high (450 mg/dL) compared with low (100 mg/dL) glucose concentration culture medium.

  5. Dexmedetomidine reduces the neuronal apoptosis related to cardiopulmonary bypass by inhibiting activation of the JAK2–STAT3 pathway

    Directory of Open Access Journals (Sweden)

    Chen Y

    2017-09-01

    Full Text Available Yanhua Chen,1,* Xu Zhang,2,* Bingdong Zhang,1 Guodong He,2 Lifang Zhou,2 Yubo Xie2 1Department of Anesthesiology, Cardiovascular Institute, 2Department of Anesthesiology, the First Affiliated Hospital of Guangxi Medical University, Nanning, China *These authors contributed equally to this work Abstract: Cardiopulmonary bypass (CPB constitutes one of the primary methodologies pertaining to cardiac surgery. However, this form of surgery can cause damage to the body. Many studies have reported that dexmedetomidine confers cerebral protection. In this study, we aimed to investigate the effect and mechanism of dexmedetomidine on neuronal apoptosis caused by CPB. Here, rats were treated with different doses of dexmedetomidine by intravenous infusion 2 hours after CPB. We observed that dexmedetomidine treatment to rats reduces the S100ß, NSE levels in plasma, and neuronal apoptosis following CPB in a dose-dependent manner. Furthermore, we observed that the beneficial effect of dexmedetomidine treatment following CPB was associated with a reduction in IL6, an inflammatory cytokine in plasma and cortex. Our results suggest that dexmedetomidine provides neuroprotective effects by inhibiting inflammation and reducing neuronal apoptosis. There was a correlation between the protective effect on the brain and the dose of dexmedetomidine. In addition, dexmedetomidine administration inhibits phosphorylation of JAK2 and STAT3 proteins in the hippocampus of rats 2 hours after CPB. Therefore, we speculate that the JAK2–STAT3 pathway plays an important role in the neuroprotective effects of dexmedetomidine following brain injury induced by CPB. Keywords: apoptosis, cardiopulmonary bypass, dexmedetomidine, neuroprotective effect, JAK2, STAT3

  6. Purified Cannabidiol, the main non-psychotropic component of Cannabis sativa, alone, counteracts neuronal apoptosis in experimental multiple sclerosis.

    Science.gov (United States)

    Giacoppo, S; Soundara Rajan, T; Galuppo, M; Pollastro, F; Grassi, G; Bramanti, P; Mazzon, E

    2015-12-01

    Multiple Sclerosis (MS) is a global concern disease leading to a progressive, chronic and demyelinating condition, affecting the central nervous system (CNS). The pathology has an inflammatory/autoimmune origin; nevertheless, neuronal cell death mechanisms are not to be underestimated. The present study was designed to test the effects of intraperitoneal administration of cannabidiol (CBD), the main non-psychotropic cannabinoid of Cannabis sativa (CS), in an experimental model of MS. The aim is to evaluate the capability of CBD administration to thwart the cascade of mediators involved in MS-induced apoptosis. Experimental Autoimmune Encephalomyelitis (EAE) was induced by immunization with myelin oligodendroglial glycoprotein (MOG)35-55 peptide in mice. After immunization, mice were observed daily for signs of EAE and weight loss. Disease signs were evaluated using a standardized scoring system. Immunohistochemical and Western blot assessments of key apoptotic markers reveal that CBD treatment is able to avoid Fas pathway activation, phospho-ERK p42/44 and cleaved caspase-3 triggering as well as alterations in mitochondrial permeability due to Bax/Bcl-2 unbalance. Moreover, CBD interferes with p53-p21 axis activation. As results, the absence of tissue apobody formation in spinal cord tissues of EAE-mice treated with CBD was established. Most of therapeutic properties of CS are currently ascribed to the psychotropic effects of phenylterpenoid delta-9 tetrahydrocannabinol. We have demonstrated that, alone, purified CBD possesses an anti-apoptotic power against the neurodegenerative processes underlying MS development. This represents an interesting new profile of CBD that could lead to its introduction in the clinical management of MS.

  7. Tetramethylpyrazine suppresses transient oxygen-glucose deprivation-induced connexin32 expression and cell apoptosis via the ERK1/2 and p38 MAPK pathway in cultured hippocampal neurons.

    Science.gov (United States)

    Gong, Gu; Yuan, Libang; Cai, Lin; Ran, Maorong; Zhang, Yulan; Gong, Huaqu; Dai, Xuemei; Wu, Wei; Dong, Hailong

    2014-01-01

    Tetramethylpyrazine (TMP) has been widely used in China as a drug for the treatment of various diseases. Recent studies have suggested that TMP has a protective effect on ischemic neuronal damage. However, the exact mechanism is still unclear. This study aims to investigate the mechanism of TMP mediated ischemic hippocampal neurons injury induced by oxygen-glucose deprivation (OGD). The effect of TMP on hippocampal neurons viability was detected by MTT assay, LDH release assay and apoptosis rate was measured by flow cytometry. TMP significantly suppressed neuron apoptosis in a concentration-dependent manner. TMP could significantly reduce the elevated levels of connexin32 (Cx32) induced by OGD. Knockdown of Cx32 by siRNA attenuated OGD injury. Moreover, our study showed that viability was increased in siRNA-Cx32-treated-neurons, and neuron apoptosis was suppressed by activating Bcl-2 expression and inhibiting Bax expression. Over expression of Cx32 could decrease neurons viability and increase LDH release. Furthermore, OGD increased phosphorylation of ERK1/2 and p38, whose inhibitors relieved the neuron injury and Cx32 up-regulation. Taken together, TMP can reverse the OGD-induced Cx32 expression and cell apoptosis via the ERK1/2 and p38 MAPK pathways.

  8. Tetramethylpyrazine suppresses transient oxygen-glucose deprivation-induced connexin32 expression and cell apoptosis via the ERK1/2 and p38 MAPK pathway in cultured hippocampal neurons.

    Directory of Open Access Journals (Sweden)

    Gu Gong

    Full Text Available Tetramethylpyrazine (TMP has been widely used in China as a drug for the treatment of various diseases. Recent studies have suggested that TMP has a protective effect on ischemic neuronal damage. However, the exact mechanism is still unclear. This study aims to investigate the mechanism of TMP mediated ischemic hippocampal neurons injury induced by oxygen-glucose deprivation (OGD. The effect of TMP on hippocampal neurons viability was detected by MTT assay, LDH release assay and apoptosis rate was measured by flow cytometry. TMP significantly suppressed neuron apoptosis in a concentration-dependent manner. TMP could significantly reduce the elevated levels of connexin32 (Cx32 induced by OGD. Knockdown of Cx32 by siRNA attenuated OGD injury. Moreover, our study showed that viability was increased in siRNA-Cx32-treated-neurons, and neuron apoptosis was suppressed by activating Bcl-2 expression and inhibiting Bax expression. Over expression of Cx32 could decrease neurons viability and increase LDH release. Furthermore, OGD increased phosphorylation of ERK1/2 and p38, whose inhibitors relieved the neuron injury and Cx32 up-regulation. Taken together, TMP can reverse the OGD-induced Cx32 expression and cell apoptosis via the ERK1/2 and p38 MAPK pathways.

  9. The neuroprotective action of pyrroloquinoline quinone against glutamate-induced apoptosis in hippocampal neurons is mediated through the activation of PI3K/Akt pathway

    International Nuclear Information System (INIS)

    Zhang Qi; Shen Mi; Ding Mei; Shen Dingding; Ding Fei

    2011-01-01

    Pyrroloquinoline quinone (PQQ), a cofactor in several enzyme-catalyzed redox reactions, possesses a potential capability of scavenging reactive oxygen species (ROS) and inhibiting cell apoptosis. In this study, we investigated the effects of PQQ on glutamate-induced cell death in primary cultured hippocampal neurons and the possible underlying mechanisms. We found that glutamate-induced apoptosis in cultured hippocampal neurons was significantly attenuated by the ensuing PQQ treatment, which also inhibited the glutamate-induced increase in Ca2+ influx, caspase-3 activity, and ROS production, and reversed the glutamate-induced decrease in Bcl-2/Bax ratio. The examination of signaling pathways revealed that PQQ treatment activated the phosphorylation of Akt and suppressed the glutamate-induced phosphorylation of c-Jun N-terminal protein kinase (JNK). And inhibition of phosphatidylinositol-3-kinase (PI3K)/Akt cascade by LY294002 and wortmannin significantly blocked the protective effects of PQQ, and alleviated the increase in Bcl-2/Bax ratio. Taken together, our results indicated that PQQ could protect primary cultured hippocampal neurons against glutamate-induced cell damage by scavenging ROS, reducing Ca2+ influx, and caspase-3 activity, and suggested that PQQ-activated PI3K/Akt signaling might be responsible for its neuroprotective action through modulation of glutamate-induced imbalance between Bcl-2 and Bax. - Research Highlights: →PQQ attenuated glutamate-induced cell apoptosis of cultured hippocampal neurons. →PQQ inhibited glutamate-induced Ca 2+ influx and caspase-3 activity. →PQQ reduced glutamate-induced increase in ROS production. →PQQ affected phosphorylation of Akt and JNK signalings after glutamate injury. →PI3K/Akt was required for neuroprotection of PQQ by modulating Bcl-2/Bax ratio.

  10. BNN27, a 17-Spiroepoxy Steroid Derivative, Interacts With and Activates p75 Neurotrophin Receptor, Rescuing Cerebellar Granule Neurons from Apoptosis.

    Science.gov (United States)

    Pediaditakis, Iosif; Kourgiantaki, Alexandra; Prousis, Kyriakos C; Potamitis, Constantinos; Xanthopoulos, Kleanthis P; Zervou, Maria; Calogeropoulou, Theodora; Charalampopoulos, Ioannis; Gravanis, Achille

    2016-01-01

    Neurotrophin receptors mediate a plethora of signals affecting neuronal survival. The p75 pan-neurotrophin receptor controls neuronal cell fate after its selective activation by immature and mature isoforms of all neurotrophins. It also exerts pleiotropic effects interacting with a variety of ligands in different neuronal or non-neuronal cells. In the present study, we explored the biophysical and functional interactions of a blood-brain-barrier (BBB) permeable, C17-spiroepoxy steroid derivative, BNN27, with p75 NTR receptor. BNN27 was recently shown to bind to NGF high-affinity receptor, TrkA. We now tested the p75 NTR -mediated effects of BNN27 in mouse Cerebellar Granule Neurons (CGNs), expressing p75 NTR , but not TrkA receptors. Our findings show that BNN27 physically interacts with p75 NTR receptors in specific amino-residues of its extracellular domain, inducing the recruitment of p75 NTR receptor to its effector protein RIP2 and the simultaneous release of RhoGDI in primary neuronal cells. Activation of the p75 NTR receptor by BNN27 reverses serum deprivation-induced apoptosis of CGNs resulting in the decrease of the phosphorylation of pro-apoptotic JNK kinase and of the cleavage of Caspase-3, effects completely abolished in CGNs, isolated from p75 NTR null mice. In conclusion, BNN27 represents a lead molecule for the development of novel p75 NTR ligands, controlling specific p75 NTR -mediated signaling of neuronal cell fate, with potential applications in therapeutics of neurodegenerative diseases and brain trauma.

  11. Glutamate-induced apoptosis in primary cortical neurons is inhibited by equine estrogens via down-regulation of caspase-3 and prevention of mitochondrial cytochrome c release

    Directory of Open Access Journals (Sweden)

    Zhang YueMei

    2005-02-01

    Full Text Available Abstract Background Apoptosis plays a key role in cell death observed in neurodegenerative diseases marked by a progressive loss of neurons as seen in Alzheimer's disease. Although the exact cause of apoptosis is not known, a number of factors such as free radicals, insufficient levels of nerve growth factors and excessive levels of glutamate have been implicated. We and others, have previously reported that in a stable HT22 neuronal cell line, glutamate induces apoptosis as indicated by DNA fragmentation and up- and down-regulation of Bax (pro-apoptotic, and Bcl-2 (anti-apoptotic genes respectively. Furthermore, these changes were reversed/inhibited by estrogens. Several lines of evidence also indicate that a family of cysteine proteases (caspases appear to play a critical role in neuronal apoptosis. The purpose of the present study is to determine in primary cultures of cortical cells, if glutamate-induced neuronal apoptosis and its inhibition by estrogens involve changes in caspase-3 protease and whether this process is mediated by Fas receptor and/or mitochondrial signal transduction pathways involving release of cytochrome c. Results In primary cultures of rat cortical cells, glutamate induced apoptosis that was associated with enhanced DNA fragmentation, morphological changes, and up-regulation of pro-caspase-3. Exposure of cortical cells to glutamate resulted in a time-dependent cell death and an increase in caspase-3 protein levels. Although the increase in caspase-3 levels was evident after 3 h, cell death was only significantly increased after 6 h. Treatment of cells for 6 h with 1 to 20 mM glutamate resulted in a 35 to 45% cell death that was associated with a 45 to 65% increase in the expression of caspase-3 protein. Pretreatment with caspase-3-protease inhibitor z-DEVD or pan-caspase inhibitor z-VAD significantly decreased glutamate-induced cell death of cortical cells. Exposure of cells to glutamate for 6 h in the presence or

  12. Metallothionein expression and roles in the CNS

    DEFF Research Database (Denmark)

    Penkowa, Milena

    2002-01-01

      Metallothioneins (MTs) are low-molecular-weight (6-7 kDa) nonenzymatic proteins (60-68 amino acid residues, 25-30% being cysteine) expressed ubiquitous in the animal kingdom. In the central nervous system (CNS), three MT isoforms are known, namely MT-I to MT-III. MT-I and MT-II (MT...

  13. Recent Developments in Quantification Methods for Metallothionein

    Czech Academy of Sciences Publication Activity Database

    Dabrio, M.; Rodriquez, A. R.; Bordin, G.; Bebiano, M. J.; De Ley, M.; Šestáková, Ivana; Vašák, M.; Nordberg, M.

    2002-01-01

    Roč. 88, č. 2 (2002), s. 123-134 ISSN 0162-0134 R&D Projects: GA MŠk OC D21.002; GA MŠk OC D8.10 Institutional research plan: CEZ:AV0Z4040901 Keywords : electrochemistry * metallothionein * mass spectrometry Subject RIV: CG - Electrochemistry Impact factor: 2.204, year: 2002

  14. Structure and Function of Vertebrate Metallothioneins

    DEFF Research Database (Denmark)

    Penkowa, Milena; Vasak, Milan; Hidalgo, Juan

    2009-01-01

    In 1957, Margoshes and Vallee reported on the isolation of a protein from horse kidney, which showed a high affinity for cadmium, and soon thereafter the protein was named metallothionein (MT) by the leading scientists Ka¨ gi and Vallee. Fifty years of intense research has dissected out many of t...

  15. The role of metallothionein in oncogenesis and cancer treatment.

    Science.gov (United States)

    Bizoń, Anna; Jędryczko, Kinga; Milnerowicz, Halina

    2017-02-14

    Metallothionein is cysteine-rich low molecular mass protein. The involvement of MT in many physiological and pathophysiological processes such as apoptosis, proliferation, angiogenesis, and the detoxification of heavy metals suggested participation of this protein in carcinogenesis and tumor therapy. Depending on the type of tissue and classification of carcinoma various it was observed relation between MT expression and tumor type, stage, grade, poor prognosis and body resistance to radiotherapy and chemotherapy. MT in tumor cell plays important role in defense mechanism against the effect of radiation by inhibiting the processes that lead to the apoptosis. A number of studies have shown an increased expression of MT in various human tumors of larynx, pancreas, kidney, uterus and breast, whereas lower MT expression was detected in liver tumors. Variable MT expression was detected in case of thyroid, prostate, lung, stomach and central nervous system tumors. Also MT plays crucial role in the cytostatics treatment. MT can bind cis-platinum compounds and removes them from the cells, which may lead to multidrug resistance. However, the same functions of MT protect against the negative effects of chemotherapeutic treatment. It is especially important in case of heart cells. Analysis of MT expression in tumor cells may be useful in choosing method of treatment. It is difficult to determine whether increased expression of MT is only a inducing factor of the development of the carcinogenesis, its malignances and multidrug resistance, or it is a factor inhibiting the induction and development of cancer.

  16. The role of metallothionein in oncogenesis and cancer treatment

    Directory of Open Access Journals (Sweden)

    Anna Bizoń

    2017-02-01

    Full Text Available Metallothionein is cysteine-rich low molecular mass protein. The involvement of MT in many physiological and pathophysiological processes such as apoptosis, proliferation, angiogenesis, and the detoxification of heavy metals suggested participation of this protein in carcinogenesis and tumor therapy.Depending on the type of tissue and classification of carcinoma various it was observed relation between MT expression and tumor type, stage, grade, poor prognosis and body resistance to radiotherapy and chemotherapy. MT in tumor cell plays important role in defense mechanism against the effect of radiation by inhibiting the processes that lead to the apoptosis. A number of studies have shown an increased expression of MT in various human tumors of larynx, pancreas, kidney, uterus and breast, whereas lower MT expression was detected in liver tumors. Variable MT expression was detected in case of thyroid, prostate, lung, stomach and central nervous system tumors.Also MT plays crucial role in the cytostatics treatment. MT can bind cis-platinum compounds and removes them from the cells, which may lead to multidrug resistance. However, the same functions of MT protect against the negative effects of chemotherapeutic treatment. It is especially important in case of heart cells.Analysis of MT expression in tumor cells may be useful in choosing method of treatment. It is difficult to determine whether increased expression of MT is only a inducing factor of the development of the carcinogenesis, its malignances and multidrug resistance, or it is a factor inhibiting the induction and development of cancer.

  17. Neuronal apoptosis and synaptic density in the dentate gyrus of ischemic rats' response to chronic mild stress and the effects of Notch signaling.

    Directory of Open Access Journals (Sweden)

    Shaohua Wang

    Full Text Available Our previous research highlighted an inconsistency with Notch1 signaling-related compensatory neurogenesis after chronic mild stress (CMS in rodents suffering from cerebral ischemia, which continue to display post-stroke depressive symptoms. Here, we hypothesize that CMS aggrandized ischemia-related apoptosis injury and worsened synaptic integrity via gamma secretase-meditated Notch1 signaling. Adult rats were exposed to a CMS paradigm after left middle cerebral artery occlusion (MCAO. Open-field and sucrose consumption testing were employed to assess depression-like behavior. Gene expression of pro-apoptotic Bax, anti-apoptotic Bcl-2, and synaptic density-related synaptophysin were measured by western blotting and real-time PCR on Day 28 after MCAO surgery. CMS induced depressive behaviors in ischemic rats, which was accompanied by an elevation in Bax/bcl-2 ratio, TUNEL staining in neurons and reduced synaptophysin expression in the dentate gyrus. These collective effects were reversed by the gamma-secretase inhibitor DAPT (N-[N-(3,5-difluorophenacetyl-L-alanyl]-S-phenyl-glycine t-butyl ester. We found that post-stroke stressors made neurons in the dentate gyrus vulnerable to apoptosis, which supports a putative role for Notch signaling in neural integrity, potentially in newborn cells' synaptic deficit with regard to preexisting cells. These findings suggest that post-stroke depression therapeutically benefits from blocking gamma secretase mediated Notch signaling, and whether this signaling pathway could be a therapeutic target needs to be further investigated.

  18. Electroacupuncture ameliorates cognitive impairment through inhibition of NF-κB-mediated neuronal cell apoptosis in cerebral ischemia-reperfusion injured rats.

    Science.gov (United States)

    Feng, Xiaodong; Yang, Shanli; Liu, Jiao; Huang, Jia; Peng, Jun; Lin, Jiumao; Tao, Jing; Chen, Lidian

    2013-05-01

    Cognitive impairment is a serious mental deficit following stroke that severely affects the quality of life of stroke survivors. Nuclear factor‑κB (NF-κB)-mediated neuronal cell apoptosis is involved in the development of post-stroke cognitive impairment; therefore, it has become a promising target for the treatment of impaired cognition. Acupuncture at the Baihui (DU20) and Shenting (DU24) acupoints is commonly used in China to clinically treat post‑stroke cognitive impairment; however, the precise mechanism of its action is largely unknown. In the present study, we evaluated the therapeutic efficacy of electroacupuncture against post-stroke cognitive impairment and investigated the underlying molecular mechanisms using a rat model of focal cerebral ischemia-reperfusion (I/R) injury. Electroacupuncture at Baihui and Shenting was identified to significantly ameliorate neurological deficits and reduce cerebral infarct volume. Additionally, electroacupuncture improved learning and memory ability in cerebral I/R injured rats, demonstrating its therapeutic efficacy against post-stroke cognitive impairment. Furthermore, electroacupuncture significantly suppressed the I/R-induced activation of NF-κB signaling in ischemic cerebral tissues. The inhibitory effect of electroacupuncture on NF-κB activation led to the inhibition of cerebral cell apoptosis. Finally, electroacupuncture markedly downregulated the expression of pro-apoptotic Bax and Fas, two critical downstream target genes of the NF-κB pathway. Collectively, our findings suggest that inhibition of NF-κB‑mediated neuronal cell apoptosis may be one mechanism via which electroacupuncture at Baihui and Shenting exerts a therapeutic effect on post-stroke cognitive impairment.

  19. Hypothyroidism in the adult rat causes incremental changes in brain-derived neurotrophic factor, neuronal and astrocyte apoptosis, gliosis, and deterioration of postsynaptic density.

    Science.gov (United States)

    Cortés, Claudia; Eugenin, Eliseo; Aliaga, Esteban; Carreño, Leandro J; Bueno, Susan M; Gonzalez, Pablo A; Gayol, Silvina; Naranjo, David; Noches, Verónica; Marassi, Michelle P; Rosenthal, Doris; Jadue, Cindy; Ibarra, Paula; Keitel, Cecilia; Wohllk, Nelson; Court, Felipe; Kalergis, Alexis M; Riedel, Claudia A

    2012-09-01

    Adult hypothyroidism is a highly prevalent condition that impairs processes, such as learning and memory. Even though tetra-iodothyronine (T(4)) treatment can overcome the hypothyroidism in the majority of cases, it cannot fully recover the patient's learning capacity and memory. In this work, we analyzed the cellular and molecular changes in the adult brain occurring with the development of experimental hypothyroidism. Adult male Sprague-Dawley rats were treated with 6-propyl-2-thiouracil (PTU) for 20 days to induce hypothyroidism. Neuronal and astrocyte apoptosis were analyzed in the hippocampus of control and hypothyroid adult rats by confocal microscopy. The content of brain-derived neurotrophic factor (BDNF) was analyzed using enzyme-linked immunosorbent assay (ELISA) and in situ hybridization. The glutamatergic synapse and the postsynaptic density (PSD) were analyzed by electron microscopy. The content of PSD proteins like tyrosine receptor kinase B (TrkB), p75, and N-methyl-D-aspartate receptor (NMDAr) were analyzed by immunoblot. We observed that the hippocampus of hypothyroid adult rats displayed increased apoptosis levels in neurons and astrocyte and reactive gliosis compared with controls. Moreover, we found that the amount of BDNF mRNA was higher in the hippocampus of hypothyroid rats and the content of TrkB, the receptor for BDNF, was reduced at the PSD of the CA3 region of hypothyroid rats, compared with controls. We also observed that the glutamatergic synapses from the stratum radiatum of CA3 from hypothyroid rats, contained thinner PSDs than control rats. This observation was in agreement with a reduced content of NMDAr subunits at the PSD in hypothyroid animals. Our data suggest that adult hypothyroidism affects the hippocampus by a mechanism that alters the composition of PSD, reduces neuronal and astrocyte survival, and alters the content of the signaling neurotrophic factors, such as BDNF.

  20. Glia Maturation Factor Dependent Inhibition of Mitochondrial PGC-1α Triggers Oxidative Stress-Mediated Apoptosis in N27 Rat Dopaminergic Neuronal Cells.

    Science.gov (United States)

    Selvakumar, Govindhasamy Pushpavathi; Iyer, Shankar S; Kempuraj, Duraisamy; Raju, Murugesan; Thangavel, Ramasamy; Saeed, Daniyal; Ahmed, Mohammad Ejaz; Zahoor, Harris; Raikwar, Sudhanshu P; Zaheer, Smita; Zaheer, Asgar

    2018-01-30

    Parkinson's disease (PD) is a progressive neurodegenerative disease affecting over five million individuals worldwide. The exact molecular events underlying PD pathogenesis are still not clearly known. Glia maturation factor (GMF), a neuroinflammatory protein in the brain plays an important role in the pathogenesis of PD. Mitochondrial dysfunctions and oxidative stress trigger apoptosis leading to dopaminergic neuronal degeneration in PD. Peroxisome proliferator-activated receptor-gamma coactivator-1 alpha (PGC-1α or PPARGC-α) acts as a transcriptional co-regulator of mitochondrial biogenesis and energy metabolism by controlling oxidative phosphorylation, antioxidant activity, and autophagy. In this study, we found that incubation of immortalized rat dopaminergic (N27) neurons with GMF influences the expression of peroxisome PGC-1α and increases oxidative stress, mitochondrial dysfunction, and apoptotic cell death. We show that incubation with GMF reduces the expression of PGC-1α with concomitant decreases in the mitochondrial complexes. Besides, there is increased oxidative stress and depolarization of mitochondrial membrane potential (MMP) in these cells. Further, GMF reduces tyrosine hydroxylase (TH) expression and shifts Bax/Bcl-2 expression resulting in release of cytochrome-c and increased activations of effector caspase expressions. Transmission electron microscopy analyses revealed alteration in the mitochondrial architecture. Our results show that GMF acts as an important upstream regulator of PGC-1α in promoting dopaminergic neuronal death through its effect on oxidative stress-mediated apoptosis. Our current data suggest that GMF is a critical risk factor for PD and suggest that it could be explored as a potential therapeutic target to inhibit PD progression.

  1. Potassium 2-(1-hydroxypentyl-benzoate attenuates neuronal apoptosis in neuron–astrocyte co-culture system through neurotrophy and neuroinflammation pathway

    Directory of Open Access Journals (Sweden)

    Dongmei Liu

    2017-09-01

    Full Text Available Potassium 2-(1-hydroxypentyl-benzoate (d,l-PHPB, a new drug candidate for ischemic stroke at the phase II clinic trial, has been shown to protect neurons by inhibiting oxidative injury and reducing neuron apoptosis in previous studies. But the mechanisms of d,l-PHPB remain to be studied. In this study, a neuron–astrocytes co-culture system was used to elucidate the roles of astrocytes in neuroprotection of d,l-PHPB under oxygen-glucose deprivation/reoxygenation (OGD/R condition. Our data showed that d,l-PHPB reduced neuronal apoptosis in mono-culture system and this effect was enhanced in neuron–astrocyte co-culture system under the OGD/R condition. Meanwhile, d,l-PHPB obviously increased the levels of brain-derived neurotrophic factor (BDNF and nerve growth factor (NGF, which were mainly secreted from astrocytes, in the co-culture system after OGD/R. The PI3K/AKT and ERK signaling pathways as well as the p-TRKA/B receptors were involved in the process. In addition, the levels of TNF-α and IL-1β secreted from astrocytes after OGD/R were markedly reduced after d,l-PHPB treatment, which was mainly due to the suppression of phosphorylated p38. In conclusion, the present study demonstrates that the neuroprotective effects of d,l-PHPB were improved by astrocytes, mainly mediated by increasing the release of BDNF/NGF and attenuating inflammatory cytokines.

  2. Metallothionein provides zinc-mediated protective effects against methamphetamine toxicity in SK-N-SH cells.

    Science.gov (United States)

    Ajjimaporn, Amornpan; Swinscoe, John; Shavali, Shaik; Govitrapong, Piyarat; Ebadi, Manuchair

    2005-11-30

    Methamphetamine (METH) is a drug of abuse and neurotoxin that induces Parkinson's-like pathology after chronic usage by targeting dopaminergic neurons. Elucidation of the intracellular mechanisms that underlie METH-induced dopaminergic neuron toxicity may help in understanding the mechanism by which neurons die in Parkinson's disease. In the present study, we examined the role of reactive oxygen species (ROS) in the METH-induced death of human dopaminergic SK-N-SH cells and further assessed the neuroprotective effects of zinc and metallothionein (MT) against METH-induced toxicity in culture. METH significantly increased the production of reactive oxygen species, decreased intracellular ATP levels and reduced the cell viability. Pre-treatment with zinc markedly prevented the loss of cell viability caused by METH treatment. Zinc pre-treatment mainly increased the expression of metallothionein and prevented the generation of reactive oxygen species and ATP depletion caused by METH. Chelation of zinc by CaEDTA caused a significant decrease in MT expression and loss of protective effects of MT against METH toxicity. These results suggest that zinc-induced MT expression protects dopaminergic neurons via preventing the accumulation of toxic reactive oxygen species and halting the decrease in ATP levels. Furthermore, MT may prevent the loss of mitochondrial functions caused by neurotoxins. In conclusion, our study suggests that MT, a potent scavenger of free radicals is neuroprotective against dopaminergic toxicity in conditions such as drug of abuse and in Parkinson's disease.

  3. Tetrahymena metallothioneins fall into two discrete subfamilies.

    Directory of Open Access Journals (Sweden)

    Silvia Díaz

    2007-03-01

    Full Text Available Metallothioneins are ubiquitous small, cysteine-rich, multifunctional proteins which can bind heavy metals.We report the results of phylogenetic and gene expression analyses that include two new Tetrahymena thermophila metallothionein genes (MTT3 and MTT5. Sequence alignments of all known Tetrahymena metallothioneins have allowed us to rationalize the structure of these proteins. We now formally subdivide the known metallothioneins from the ciliate genus Tetrahymena into two well defined subfamilies, 7a and 7b, based on phylogenetic analysis, on the pattern of clustering of Cys residues, and on the pattern of inducibility by the heavy metals Cd and Cu. Sequence alignment also reveals a remarkably regular, conserved and hierarchical modular structure of all five subfamily 7a MTs, which include MTT3 and MTT5. The former has three modules, while the latter has only two. Induction levels of the three T. thermophila genes were determined using quantitative real time RT-PCR. Various stressors (including heavy metals brought about dramatically different fold-inductions for each gene; MTT5 showed the highest fold-induction. Conserved DNA motifs with potential regulatory significance were identified, in an unbiased way, upstream of the start codons of subfamily 7a MTs. EST evidence for alternative splicing in the 3' UTR of the MTT5 mRNA with potential regulatory activity is reported.The small number and remarkably regular structure of Tetrahymena MTs, coupled with the experimental tractability of this model organism for studies of in vivo function, make it an attractive system for the experimental dissection of the roles, structure/function relationships, regulation of gene expression, and adaptive evolution of these proteins, as well as for the development of biotechnological applications for the environmental monitoring of toxic substances.

  4. Insect peptide CopA3-induced protein degradation of p27Kip1 stimulates proliferation and protects neuronal cells from apoptosis

    International Nuclear Information System (INIS)

    Nam, Seung Taek; Kim, Dae Hong; Lee, Min Bum; Nam, Hyo Jung; Kang, Jin Ku; Park, Mi Jung; Lee, Ik Hwan; Seok, Heon; Lee, Dong Gun; Hwang, Jae Sam; Kim, Ho

    2013-01-01

    Highlights: •CopA3 peptide isolated from the Korean dung beetle has antimicrobial activity. •Our study reported that CopA3 has anticancer and immunosuppressive effects. •We here demonstrated that CopA3 has neurotropic and neuroprotective effects. •CopA3 degrades p27Kip1 protein and this mediates effects of CopA3 on neuronal cells. -- Abstract: We recently demonstrated that the antibacterial peptide, CopA3 (a D-type disulfide dimer peptide, LLCIALRKK), inhibits LPS-induced macrophage activation and also has anticancer activity in leukemia cells. Here, we examined whether CopA3 could affect neuronal cell proliferation. We found that CopA3 time-dependently increased cell proliferation by up to 31 ± 2% in human neuroblastoma SH-SY5Y cells, and up to 29 ± 2% in neural stem cells isolated from neonatal mouse brains. In both cell types, CopA3 also significantly inhibited the apoptosis and viability losses caused by 6-hydroxy dopamine (a Parkinson disease-mimicking agent) and okadaic acid (an Alzheimer’s disease-mimicking agent). Immunoblotting revealed that the p27Kip1 protein (a negative regulator of cell cycle progression) was markedly degraded in CopA3-treated SH-SY5Y cells. Conversely, an adenovirus expressing p27Kip1 significantly inhibited the antiapoptotic effects of CopA3 against 6-hydroxy dopamine- and okadaic acid-induced apoptosis, and decreased the neurotropic effects of CopA3. These results collectively suggest that CopA3-mediated protein degradation of p27Kip1 may be the main mechanism through which CopA3 exerts neuroprotective and neurotropic effects

  5. Insect peptide CopA3-induced protein degradation of p27Kip1 stimulates proliferation and protects neuronal cells from apoptosis

    Energy Technology Data Exchange (ETDEWEB)

    Nam, Seung Taek; Kim, Dae Hong; Lee, Min Bum; Nam, Hyo Jung; Kang, Jin Ku; Park, Mi Jung; Lee, Ik Hwan [Department of Life Science, College of Natural Science, Daejin University, Pocheon, Gyeonggido 487-711 (Korea, Republic of); Seok, Heon [Department of Biomedical Science, Jungwon University, Goesan, Chungcheongbukdo 367-700 (Korea, Republic of); Lee, Dong Gun [School of Life Sciences and Biotechnology, College of Natural Sciences, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Hwang, Jae Sam [Department of Agricultural Biology, National Academy of Agricultural Science, RDA, Suwon 441-707 (Korea, Republic of); Kim, Ho, E-mail: hokim@daejin.ac.kr [Department of Life Science, College of Natural Science, Daejin University, Pocheon, Gyeonggido 487-711 (Korea, Republic of)

    2013-07-19

    Highlights: •CopA3 peptide isolated from the Korean dung beetle has antimicrobial activity. •Our study reported that CopA3 has anticancer and immunosuppressive effects. •We here demonstrated that CopA3 has neurotropic and neuroprotective effects. •CopA3 degrades p27Kip1 protein and this mediates effects of CopA3 on neuronal cells. -- Abstract: We recently demonstrated that the antibacterial peptide, CopA3 (a D-type disulfide dimer peptide, LLCIALRKK), inhibits LPS-induced macrophage activation and also has anticancer activity in leukemia cells. Here, we examined whether CopA3 could affect neuronal cell proliferation. We found that CopA3 time-dependently increased cell proliferation by up to 31 ± 2% in human neuroblastoma SH-SY5Y cells, and up to 29 ± 2% in neural stem cells isolated from neonatal mouse brains. In both cell types, CopA3 also significantly inhibited the apoptosis and viability losses caused by 6-hydroxy dopamine (a Parkinson disease-mimicking agent) and okadaic acid (an Alzheimer’s disease-mimicking agent). Immunoblotting revealed that the p27Kip1 protein (a negative regulator of cell cycle progression) was markedly degraded in CopA3-treated SH-SY5Y cells. Conversely, an adenovirus expressing p27Kip1 significantly inhibited the antiapoptotic effects of CopA3 against 6-hydroxy dopamine- and okadaic acid-induced apoptosis, and decreased the neurotropic effects of CopA3. These results collectively suggest that CopA3-mediated protein degradation of p27Kip1 may be the main mechanism through which CopA3 exerts neuroprotective and neurotropic effects.

  6. Injection of Aβ1-40 into hippocampus induced cognitive lesion associated with neuronal apoptosis and multiple gene expressions in the tree shrew.

    Science.gov (United States)

    Lin, Na; Xiong, Liu-Lin; Zhang, Rong-Ping; Zheng, Hong; Wang, Lei; Qian, Zhong-Yi; Zhang, Piao; Chen, Zhi-Wei; Gao, Fa-Bao; Wang, Ting-Hua

    2016-05-01

    Alzheimer's disease (AD) can incur significant health care costs to the patient, their families, and society; furthermore, effective treatments are limited, as the mechanisms of AD are not fully understood. This study utilized twelve adult male tree shrews (TS), which were randomly divided into PBS and amyloidbetapeptide1-40 (Aβ1-40) groups. AD model was established via an intracerebroventricular (icv) injection of Aβ1-40 after being incubated for 4 days at 37 °C. Behavioral, pathophysiological and molecular changes were evaluated by hippocampal-dependent tasks, magnetic resonance imaging (MRI), silver staining, hematoxylin-eosin (HE) staining, TUNEL assay and gene sequencing, respectively. At 4 weeks post-injection, as compared with the PBS group, in Aβ1-40 injected animals: cognitive impairments happened, and the hippocampus had atrophied indicated by MRI findings; meanwhile, HE staining showed the cells of the CA3 and DG were significantly thinner and smaller. The average number of cells in the DG, but not the CA3, was also significantly reduced; furthermore, silver staining revealed neurotic plaques and neurofibrillary tangles (NFTs) in the hippocampi; TUNEL assay showed many cells exhibited apoptosis, which was associated with downregulated BCL-2/BCL-XL-associated death promoter (Bad), inhibitor of apoptosis protein (IAP), Cytochrome c (CytC) and upregulated tumor necrosis factor receptor 1 (TNF-R1); lastly, gene sequencing reported a total of 924 mobilized genes, among which 13 of the downregulated and 19 of the upregulated genes were common to the AD pathway. The present study not only established AD models in TS, but also reported on the underlying mechanism involved in neuronal apoptosis associated with multiple gene expression.

  7. Postconditioning with sevoflurane ameliorates spatial learning and memory deficit via attenuating endoplasmic reticulum stress induced neuron apoptosis in a rat model of hemorrhage shock and resuscitation.

    Science.gov (United States)

    Hu, Xianwen; Wang, Jingxian; Zhang, Li; Zhang, Qiquan; Duan, Xiaowen; Zhang, Ye

    2018-06-02

    Hemorrhage shock could initiate endoplasmic reticulum stress (ERS) and then induce neuronal apoptosis. The aim of this study was to investigate whether sevoflurane postconditioning could attenuate brain injury via suppressing apoptosis induced by ERS. Seventy male rats were randomized into five groups: sham, shock, low concentration (sevo1, 1.2%), middle concentration (sevo2, 2.4%) and high concentration (sevo3, 3.6%) of sevoflurane postconditioning. Hemorrhage shock was induced by removing 40% of the total blood volume during an interval of 30 min. 1h after the completion of bleeding, the animals were reinfused with shed blood during the ensuing 30 min. The spatial learning and memory ability of rats were measured by Morris water maze (MWM) test three days after the operation. Terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) positive cells in the hippocampus CA1 region were assessed after the MWM test. The expression of C/EBP-homologousprotein (CHOP) and glucose-regulated protein 78 (GRP78) in the hippocampus were measured at 24h after reperfusion. We found that sevoflurane postconditioning with the concentrations of 2.4% and 3.6% significantly ameliorated the spatial learning and memory ability, decreased the TUNEL-positive cells, and reduced the GRP78 and CHOP expression compared with the shock group. These results suggested that sevoflurane postconditioning with the concentrations of 2.4% and 3.6% could ameliorate spatial learning and memory deficit after hemorrhage shock and resuscitation injury via suppressing apoptosis induced by ERS. Copyright © 2018. Published by Elsevier B.V.

  8. A Review of Metallothionein Isoforms and their Role in Pathophysiology

    Directory of Open Access Journals (Sweden)

    Senthil kumar M

    2011-05-01

    Full Text Available Abstract The Metallothionein (MT is a protein which has several interesting biological effects and has been demonstrated increase focus on the role of MT in various biological systems in the past three decades. The studies on the role of MT were limited with few areas like apoptosis and antioxidants in selected organs even fifty years after its discovery. Now acknowledge the exploration of various isoforms of MT such as MT-I, MT-II, MT-III and MT-IV and other isoforms in various biological systems. Strong evidence exists that MT modulates complex diseases and the immune system in the body but the primary function of MT still remains unknown. This review's main objective is to explore the capability to specifically manipulate MT levels in cells and in animals to provide answers regarding how MT could impact those complex disease scenarios. The experimental result mentioned in this review related among MT, zinc, cadmium, diabetic, heart disease, bone retardation, neuro toxicity, kidney dysfunction, cancer, and brain suggest novel method for exploration and contribute significantly to the growing scientist to research further in this field.

  9. Erythrocyte metallothionein as an index of zinc status in humans

    International Nuclear Information System (INIS)

    Grider, A.; Bailey, L.B.; Cousins, R.J.

    1990-01-01

    Metallothionein concentrations in erythrocyte lysates derived from human subjects were measured by an ELISA procedure. IgG obtained from serum of sheep injected with human metallothionein 1 was used in this competitive assay. Subjects were fed a semipurified zinc-deficient diet for an 8-day depletion period after 3 days of acclimation. Fasting plasma zinc concentrations were reduced ∼7%. Metallothionein in the erythrocyte lysates was significantly decreased to 59% of the initial level by the end of the depletion period. Supplementation of these depleted subjects with zinc did not increase erythrocyte metallothionein levels within 24 hr. Daily supplementation of control subjects with zinc increased erythrocyte metallothionein to a 7-fold maximum within 7 days. These levels were reduced by 61% within 14 days after zinc supplementation was terminated. Incubation of rat [ 35 S]metallothionein with human erythrocyte lysate showed a time-dependent increase in 35 S soluble in 20% trichloroacetic acid, indicating degradation of the labeled protein, presumably via protease activity in the lysate. It is proposed that zinc supplementation induces erythrocyte metallothionein during erythropoiesis and that low zinc intake decreases synthesis and/or accelerates degradation of the protein in reticulocytes/erythrocytes. Metallothionein levels in erythrocytes may provide a useful index upon which to assess zinc status in humans

  10. Some commonly used brominated flame retardants cause Ca2+-ATPase inhibition, beta-amyloid peptide release and apoptosis in SH-SY5Y neuronal cells.

    Directory of Open Access Journals (Sweden)

    Fawaz Al-Mousa

    Full Text Available Brominated flame retardants (BFRs are chemicals commonly used to reduce the flammability of consumer products and are considered pollutants since they have become widely dispersed throughout the environment and have also been shown to bio-accumulate within animals and man. This study investigated the cytotoxicity of some of the most commonly used groups of BFRs on SH-SY5Y human neuroblastoma cells. The results showed that of the BFRs tested, hexabromocyclododecane (HBCD, tetrabromobisphenol-A (TBBPA and decabromodiphenyl ether (DBPE, all are cytotoxic at low micromolar concentrations (LC(50 being 2.7 ± 0.7 µM, 15 ± 4 µM and 28 ± 7 µM, respectively. They induced cell death, at least in part, by apoptosis through activation of caspases. They also increased intracellular [Ca(2+] levels and reactive-oxygen-species within these neuronal cells. Furthermore, these BFRs also caused rapid depolarization of the mitochondria and cytochrome c release in these neuronal cells. Elevated intracellular [Ca(2+] levels appear to occur through a mechanism involving microsomal Ca(2+-ATPase inhibition and this maybe responsible for Ca(2+-induced mitochondrial dysfunction. In addition, µM levels of these BFRs caused β-amyloid peptide (Aβ-42 processing and release from these cells with a few hours of exposure. These results therefore shows that these pollutants are both neurotoxic and amyloidogenic in-vitro.

  11. [Expression of proteasome subunits PSMB5 and PSMB9 mRNA in hippocampal neurons in experimental diabetes mellitus: link with apoptosis and necrosis].

    Science.gov (United States)

    Lebid', Iu V; Dosenko, V Ie; Skybo, H H

    2010-01-01

    There is a huge body of evidence showing that long-termed diabetes mellitus is followed with hippocampal dysfunction. The goal of this work was to investigate the expression of proteasome subunits PSMB5 and PSMB9 mRNA in CA1, CA2 and CA3 areas of hippocampus in parallel with processes of cell death (apoptosis and necrosis) in development dynamics of streptozotocine-induced diabetes. We have studied hippocampal neurons using chromatine dye Hoechst-33342 and immunohistochemical detection of apoptotic cell death marker caspase-3. At day 3 and 7 after injection of streptozotocine we have performed visualization of caspase-3-immunopositive neurons showing signs of neurodegeneration in hippocampal sections using confocal microscope Olympus FV1000. The rate of proteasome subunits PSMB5 and PSMB9 mRNA expression was determined with RT-PCR. The results indicated elevation of PSMB9 mRNA content (from 4807 +/- 0.392 arbU up to 20,023 +/- 4949 arbU on day 3 and up to 20,253 +/- 5141 arbU on day 7). A maximal number of cells with signs of chromatin condensation was observed at day 3 and day 7 in CA2 and CA3 area (11.51% and 12.49% respectively). That indicates an intensification of proapoptotic processes. Summarizing the results presented above we can conclude that during the first week of diabetes mellitus development, hippocampal cells undergo the process of impairment and degeneration.

  12. Blockade of NMDA receptor subtype NR2B prevents seizures but not apoptosis of dentate gyrus neurons in bacterial meningitis in infant rats

    Science.gov (United States)

    Kolarova, Anna; Ringer, Ralph; Täuber, Martin G; Leib, Stephen L

    2003-01-01

    Background Excitotoxic neuronal injury by action of the glutamate receptors of the N-methyl-d-aspartate (NMDA) subtype have been implicated in the pathogenesis of brain damage as a consequence of bacterial meningitis. The most potent and selective blocker of NMDA receptors containing the NR2B subunit is (R,S)-alpha-(4-hydroxyphenyl)-beta-methyl-4-(phenylmethyl)-1-piperid inepropanol (RO 25-6981). Here we evaluated the effect of RO 25-6981 on hippocampal neuronal apoptosis in an infant rat model of meningitis due to Streptococcus pneumoniae. Animals were randomized for treatment with RO 25-6981 at a dosage of either 0.375 mg (15 mg/kg; n = 28) or 3.75 mg (150 mg/kg; n = 15) every 3 h or an equal volume of sterile saline (250 μl; n = 40) starting at 12 h after infection. Eighteen hours after infection, animals were assessed clinically and seizures were observed for a period of 2 h. At 24 h after infection animals were sacrificed and brains were examined for apoptotic injury to the dentate granule cell layer of the hippocampus. Results Treatment with RO 25-6981 had no effect on clinical scores, but the incidence of seizures was reduced (P < 0.05 for all RO 25-6981 treated animals combined). The extent of apoptosis was not affected by low or high doses of RO 25-6981. Number of apoptotic cells (median [range]) was 12.76 [3.16–25.3] in animals treated with low dose RO 25-6981 (control animals 13.8 [2.60–31.8]; (P = NS) and 9.8 [1.7–27.3] (controls: 10.5 [2.4–21.75]) in animals treated with high dose RO 25-6981 (P = NS). Conclusions Treatment with a highly selective blocker of NMDA receptors containing the NR2B subunit failed to protect hippocampal neurons from injury in this model of pneumococcal meningitis, while it had some beneficial effect on the incidence of seizures. PMID:13129439

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

    Science.gov (United States)

    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.

  14. Blockade of NMDA receptor subtype NR2B prevents seizures but not apoptosis of dentate gyrus neurons in bacterial meningitis in infant rats

    Directory of Open Access Journals (Sweden)

    Täuber Martin G

    2003-09-01

    Full Text Available Abstract Background Excitotoxic neuronal injury by action of the glutamate receptors of the N-methyl-d-aspartate (NMDA subtype have been implicated in the pathogenesis of brain damage as a consequence of bacterial meningitis. The most potent and selective blocker of NMDA receptors containing the NR2B subunit is (R,S-alpha-(4-hydroxyphenyl-beta-methyl-4-(phenylmethyl-1-piperid inepropanol (RO 25-6981. Here we evaluated the effect of RO 25-6981 on hippocampal neuronal apoptosis in an infant rat model of meningitis due to Streptococcus pneumoniae. Animals were randomized for treatment with RO 25-6981 at a dosage of either 0.375 mg (15 mg/kg; n = 28 or 3.75 mg (150 mg/kg; n = 15 every 3 h or an equal volume of sterile saline (250 μl; n = 40 starting at 12 h after infection. Eighteen hours after infection, animals were assessed clinically and seizures were observed for a period of 2 h. At 24 h after infection animals were sacrificed and brains were examined for apoptotic injury to the dentate granule cell layer of the hippocampus. Results Treatment with RO 25-6981 had no effect on clinical scores, but the incidence of seizures was reduced (P Conclusions Treatment with a highly selective blocker of NMDA receptors containing the NR2B subunit failed to protect hippocampal neurons from injury in this model of pneumococcal meningitis, while it had some beneficial effect on the incidence of seizures.

  15. Dopamine-induced apoptosis in human neuronal cells: inhibition by nucleic acides antisense to the dopamine transporter

    International Nuclear Information System (INIS)

    Porat, S.; Gabbay, M.; Tauber, M.; Ratovitski, T.; Blinder, E.; Simantov, R.

    1996-01-01

    Human neuroblastoma NMB cells take up [ 3 H]dopamine in a selective manner indicating that dopamine transporters are responsible for this uptake. These cells were therefore used as a model to study dopamine neurotoxicity, and to elucidate the role of dopamine transporters in controlling cell death. Treatment with 0.05-0.4 mM dopamine changed cells' morphology within 4 h, accompanied by retraction of processes, shrinkage, apoptosis-like atrophy, accumulation of apoptotic particles, DNA fragmentation and cell death. Cycloheximide inhibited dopamine's effect, suggesting that induction of apoptosis by dopamine was dependent upon protein synthesis. Dopamine cytotoxicity, monitored morphologically by flow cytometric analysis, and by lactate dehydrogenase released, was blocked by cocaine but not by the noradrenaline and serotonin uptake blockers desimipramine and imipramine, respectively. Attempting to inhibit dopamine transport and toxicity in a drug-free and highly selective way, three 18-mer dopamine transporter antisense phosphorothioate oligonucleotides (numbers 1, 2 and 3) and a new plasmid vector expressing the entire rat dopamine transporter complementary DNA in the antisense orientation were prepared and tested. Antisense phosphorothioate oligonucleotide 3 inhibited [ 3 H]dopamine uptake in a time- and dose-dependent manner. Likewise, transient transfection of NMB cells with the plasmid expressing dopamine transporter complementary DNA in the antisense orientation partially blocked [ 3 H]dopamine uptake. Antisense phosphorothioate oligonucleotide 3 also decreased, dose-dependently, the toxic effect of dopamine and 6-hydroxydopamine. Western blot analysis with newly prepared anti-human dopamine transporter antibodies showed that antisense phosphorothioate oligonucleotide 3 decreased the transporter protein level. These studies contribute to better understand the mechanism of dopamine-induced apoptosis and neurotoxicity. (Copyright (c) 1996 Elsevier Science B

  16. The signalling axis mediating neuronal apoptosis in response to [Pt(O,O'-acac)(γ-acac)(DMS)].

    Science.gov (United States)

    Muscella, Antonella; Calabriso, Nadia; Vetrugno, Carla; Fanizzi, Francesco Paolo; De Pascali, Sandra Angelica; Marsigliante, Santo

    2011-06-01

    It was previously shown that [Pt(O,O'-acac)(γ-acac)(DMS)] induces apoptosis in various cancer cells and exerts antimetastatic responses in vitro. In rats, [Pt(O,O'-acac)(γ-acac)(DMS)] reaches the central nervous system in quantities higher than cisplatin causing less excitotoxicity. The aim of the present paper was to investigate whether [Pt(O,O'-acac)(γ-acac)(DMS)] is able to exert cytotoxic effects on SH-SY5Y human neuroblastoma cell line, and to study the intracellular transduction mechanisms underlying these effects. Here we have demonstrated that [Pt(O,O'-acac)(γ-acac)(DMS)] was more effective than cisplatin in provoking apoptosis characterized by: (a) mitochondria depolarization, (b) decrease of Bcl-2 expression and increase of BAX expressions with cytosol-to-mitochondria translocation, (c) activation of caspase-7 and -9 and (d) generation of reactive oxygen species (ROS). [Pt(O,O'-acac)(γ-acac)(DMS)] provoked the activation of the following signalling kinases that were interacting with each other: PKC-δ and -ɛ, ERK1/2, p38MAPK, JNK1/2, NF-κB, c-src and FAK. We found that ROS generated by NADPH oxidase was responsible for the [Pt(O,O'-acac)(γ-acac)(DMS)]-mediated PKC-δ and -ɛ activation and consequential phosphorylation of all MAPKs. [Pt(O,O'-acac)(γ-acac)(DMS)]-induced mitochondrial apoptosis was blocked when p38MAPK and JNK1/2 were inhibited, whilst the effects on Bax/Bcl-2 mRNA and protein levels were blocked inhibiting NF-κB. NF-κB nuclear translocation was blocked inhibiting MEK1/2 activity. In addition to the induction of apoptosis [Pt(O,O'-acac)(γ-acac)(DMS)] downregulated pro-survival pathway. Survival inhibition started from mitochondrial ROS generation which induced c-src, FAK and Akt activation. In conclusion, our results suggest that [Pt(O,O'-acac)(γ-acac)(DMS)] may be considered a promising compound for the treatment of neuroblastoma. Further studies are warranted to explore in detail the therapeutic potential of this compound

  17. Metallothionein deficiency aggravates depleted uranium-induced nephrotoxicity

    International Nuclear Information System (INIS)

    Hao, Yuhui; Huang, Jiawei; Gu, Ying; Liu, Cong; Li, Hong; Liu, Jing; Ren, Jiong; Yang, Zhangyou; Peng, Shuangqing; Wang, Weidong; Li, Rong

    2015-01-01

    Depleted uranium (DU) has been widely used in both civilian and military activities, and the kidney is the main target organ of DU during acute high-dose exposures. In this study, the nephrotoxicity caused by DU in metallothionein-1/2-null mice (MT −/−) and corresponding wild-type (MT +/+) mice was investigated to determine any associations with MT. Each MT −/− or MT +/+ mouse was pretreated with a single dose of DU (10 mg/kg, intraperitoneal injection) or an equivalent volume of saline. After 4 days of DU administration, kidney changes were assessed. After DU exposure, serum creatinine and serum urea nitrogen in MT −/− mice significantly increased than in MT +/+ mice, with more severe kidney pathological damage. Moreover, catalase and superoxide dismutase (SOD) decreased, and generation of reactive oxygen species and malondialdehyde increased in MT −/− mice. The apoptosis rate in MT −/− mice significantly increased, with a significant increase in both Bax and caspase 3 and a decrease in Bcl-2. Furthermore, sodium-glucose cotransporter (SGLT) and sodium-phosphate cotransporter (NaPi-II) were significantly reduced after DU exposure, and the change of SGLT was more evident in MT −/− mice. Finally, exogenous MT was used to evaluate the correlation between kidney changes induced by DU and MT doses in MT −/− mice. The results showed that, the pathological damage and cell apoptosis decreased, and SOD and SGLT levels increased with increasing dose of MT. In conclusion, MT deficiency aggravated DU-induced nephrotoxicity, and the molecular mechanisms appeared to be related to the increased oxidative stress and apoptosis, and decreased SGLT expression. - Highlights: • MT −/− and MT +/+ mice were used to evaluate nephrotoxicity of DU. • Renal damage was more evident in the MT −/− mice after exposure to DU. • Exogenous MT also protects against DU-induced nephrotoxicity. • MT deficiency induced more ROS and apoptosis after exposure to

  18. Metallothionein deficiency aggravates depleted uranium-induced nephrotoxicity

    Energy Technology Data Exchange (ETDEWEB)

    Hao, Yuhui; Huang, Jiawei; Gu, Ying; Liu, Cong; Li, Hong; Liu, Jing; Ren, Jiong; Yang, Zhangyou [State Key Laboratory of Trauma, Burns and Combined Injury, Institute of Combined Injury, Chongqing Engineering Research Center for Nanomedicine, College of Preventive Medicine, Third Military Medical University, No. 30 Gaotanyan Street, Shapingba District, Chongqing 400038 (China); Peng, Shuangqing [Evaluation and Research Center for Toxicology, Institute of Disease Control and Prevention, Academy of Military Medical Science, 20 Dongdajie Street, Fengtai District, Beijing 100071 (China); Wang, Weidong, E-mail: wwdwyl@sina.com [Department of Radiation Oncology, Shanghai Jiao Tong University Affiliated Sixth People' s Hospital, Shanghai 200233 (China); Li, Rong, E-mail: yuhui_hao@126.com [State Key Laboratory of Trauma, Burns and Combined Injury, Institute of Combined Injury, Chongqing Engineering Research Center for Nanomedicine, College of Preventive Medicine, Third Military Medical University, No. 30 Gaotanyan Street, Shapingba District, Chongqing 400038 (China)

    2015-09-15

    Depleted uranium (DU) has been widely used in both civilian and military activities, and the kidney is the main target organ of DU during acute high-dose exposures. In this study, the nephrotoxicity caused by DU in metallothionein-1/2-null mice (MT −/−) and corresponding wild-type (MT +/+) mice was investigated to determine any associations with MT. Each MT −/− or MT +/+ mouse was pretreated with a single dose of DU (10 mg/kg, intraperitoneal injection) or an equivalent volume of saline. After 4 days of DU administration, kidney changes were assessed. After DU exposure, serum creatinine and serum urea nitrogen in MT −/− mice significantly increased than in MT +/+ mice, with more severe kidney pathological damage. Moreover, catalase and superoxide dismutase (SOD) decreased, and generation of reactive oxygen species and malondialdehyde increased in MT −/− mice. The apoptosis rate in MT −/− mice significantly increased, with a significant increase in both Bax and caspase 3 and a decrease in Bcl-2. Furthermore, sodium-glucose cotransporter (SGLT) and sodium-phosphate cotransporter (NaPi-II) were significantly reduced after DU exposure, and the change of SGLT was more evident in MT −/− mice. Finally, exogenous MT was used to evaluate the correlation between kidney changes induced by DU and MT doses in MT −/− mice. The results showed that, the pathological damage and cell apoptosis decreased, and SOD and SGLT levels increased with increasing dose of MT. In conclusion, MT deficiency aggravated DU-induced nephrotoxicity, and the molecular mechanisms appeared to be related to the increased oxidative stress and apoptosis, and decreased SGLT expression. - Highlights: • MT −/− and MT +/+ mice were used to evaluate nephrotoxicity of DU. • Renal damage was more evident in the MT −/− mice after exposure to DU. • Exogenous MT also protects against DU-induced nephrotoxicity. • MT deficiency induced more ROS and apoptosis after exposure to

  19. Fipronil is a powerful uncoupler of oxidative phosphorylation that triggers apoptosis in human neuronal cell line SHSY5Y.

    Science.gov (United States)

    Vidau, Cyril; González-Polo, Rosa A; Niso-Santano, Mireia; Gómez-Sánchez, Rubén; Bravo-San Pedro, José M; Pizarro-Estrella, Elisa; Blasco, Rafael; Brunet, Jean-Luc; Belzunces, Luc P; Fuentes, José M

    2011-12-01

    Fipronil is a phenylpyrazole insecticide known to elicit neurotoxicity via an interaction with ionotropic receptors, namely GABA and glutamate receptors. Recently, we showed that fipronil and other phenylpyrazole compounds trigger cell death in Caco-2 cells. In this study, we investigated the mode of action and the type of cell death induced by fipronil in SH-SY5Y human neuroblastoma cells. Flow cytometric and western blot analyses demonstrated that fipronil induces cellular events belonging to the apoptosis process, such as mitochondrial potential collapse, cytochrome c release, caspase-3 activation, nuclear condensation and phosphatidylserine externalization. In addition, fipronil induces a rapid ATP depletion with concomitant activation of anaerobic glycolysis. This cellular response is characteristic of mitochondrial injury associated with a defect of the respiration process. Therefore, we also investigated the effect of fipronil on the oxygen consumption in isolated mitochondria. Interestingly, we show for the first time that fipronil is a strong uncoupler of oxidative phosphorylation at relative low concentrations. Thus in this study, we report a new mode of action by which the insecticide fipronil could triggers apoptosis. Copyright © 2011 Elsevier Inc. All rights reserved.

  20. Metallothioneins are multipurpose neuroprotectants during brain pathology

    DEFF Research Database (Denmark)

    Penkowa, Milena

    2006-01-01

    Metallothioneins (MTs) constitute a family of cysteine-rich metalloproteins involved in cytoprotection during pathology. In mammals there are four isoforms (MT-I - IV), of which MT-I and -II (MT-I + II) are the best characterized MT proteins in the brain. Accumulating studies have demonstrated MT......-I overexpression demonstrated the importance of MT-I + II for coping with brain pathology. In addition, exogenous MT-I or MT-II injected intraperitoneally is able to promote similar effects as those of endogenous MT-I + II, which indicates that MT-I + II have both extra- and intracellular actions. In injured brain...

  1. Puerarin reduces apoptosis in rat hippocampal neurons culturea in high glucose medium by modulating the p38 mitogen activated protein kinase and c-Jun N-terminal kinase signaling pathways.

    Science.gov (United States)

    Xu, Xiaohan; Wang, Jingbo; Zhang, Hong; Tian, Guoqing; Liu, Yuqin

    2016-02-01

    To investigate the neuroprotective etfect of puerarin on rat hippocampal neurons cultured in high glucose medium, and to examine the role of the p38 mitogen activated protein kinase (p38 MAPK) and c-Jun N-terminal kinase (JNK) signaling pathways in this effect. Primary cultures of hippocampal neurons were prepared from newborn Sprague Dawley rats. Neuron-specific enolase immunocytochemistry was used to identify neurons. The neurons were cultured with normal medium (control group) or with high-glucose medium (high-glucose group), and puerarin (puerarin group), a p38 MAPK inhibitor (SB239063; p38 MAPK inhibitor group) or a JNK inhibitor (SP600125; JNK inhibitor group) were added. After 72 h of treatment, terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling assay was performed to detect apoptosis, and western blotting was used to assess protein levels of p-p38, p38, p-JNK and JNK. In the high-glucose group, the neuronal apoptosis rate and the p-p38/p38 and p-JNK/JNK ratios were higher than in the control group. The p38 MAPK and JNK inhibitors prevented this increase in the apoptosis rate. The apoptosis rates in the puerarin group, the p38 MAPK inhibitor group and the JNK inhibitor group were significantly decreased compared with the high-glucose group. Moreover, protein levels of p-p38 and p-JNK were significantly reduced, and the p-p38/p38 and p-JNK/JNK ratios were decreased in the puerarin group compared with the high-glucose group. In addition, compared with the high-glucose group, p-p38 levels and the p-p38/p38 ratio were reduced in the p38 MAPK inhibitor group, and p-JNK levels and the p-JNK/JNK ratio were decreased in the JNK inhibitor group. Puerarin attenuates neuronal apoptosis induced by high glucose by reducing the phosphorylation of p38 and JNK.

  2. Is Chronic Curcumin Supplementation Neuroprotective Against Ischemia for Antioxidant Activity, Neurological Deficit, or Neuronal Apoptosis in an Experimental Stroke Model?

    Science.gov (United States)

    Altinay, Serdar; Cabalar, Murat; Isler, Cihan; Yildirim, Funda; Celik, Duygu S; Zengi, Oguzhan; Tas, Abdurrahim; Gulcubuk, Ahmet

    2017-01-01

    To investigate the neuroprotective effect of chronic curcumin supplementation on the rat forebrain prior to ischemia and reperfusion. Forebrain ischemia was induced by bilateral common carotid artery occlusion for 1/2 hour, followed by reperfusion for 72 hours. Older rats were divided into five groups: Group I received 300 mg/kg oral curcumin for 21 days before ischemia and 300 mg/kg intraperitoneal curcumin after ischemia; Group II received 300 mg/kg intraperitoneal curcumin after ischemia; Group III received 300 mg/kg oral curcumin for 21 days before ischemia; Group IV had only ischemia; Group V was the sham-operated group. The forebrain was rapidly dissected for biochemical parameter assessment and histopathological examination. In forebrain tissue, enzyme activities of superoxide dismutase, glutathione peroxidase, and catalase were significantly higher in Group I than Groups II or III (p curcumin-treated groups compared with the ischemic group. We also found a marked reduction in apoptotic index after 72 hours in the groups receiving curcumin. Significantly more TUNEL-positive cells were observed in the ischemic group compared to those treated with curcumin. We demonstrated the neuroprotective effect of chronic curcumin supplement on biochemical parameters, neurological scores and apoptosis following ischemia and reperfusion injury in rats.

  3. Impaired cross-talk between the thioredoxin and glutathione systems is related to ASK-1 mediated apoptosis in neuronal cells exposed to mercury.

    Science.gov (United States)

    Branco, Vasco; Coppo, Lucia; Solá, Susana; Lu, Jun; Rodrigues, Cecília M P; Holmgren, Arne; Carvalho, Cristina

    2017-10-01

    Mercury (Hg) compounds target both cysteine (Cys) and selenocysteine (Sec) residues in peptides and proteins. Thus, the components of the two major cellular antioxidant systems - glutathione (GSH) and thioredoxin (Trx) systems - are likely targets for mercurials. Hg exposure results in GSH depletion and Trx and thioredoxin reductase (TrxR) are prime targets for mercury. These systems have a wide-range of common functions and interaction between their components has been reported. However, toxic effects over both systems are normally treated as isolated events. To study how the interaction between the glutathione and thioredoxin systems is affected by Hg, human neuroblastoma (SH-SY5Y) cells were exposed to 1 and 5μM of inorganic mercury (Hg 2+ ), methylmercury (MeHg) or ethylmercury (EtHg) and examined for TrxR, GSH and Grx levels and activities, as well as for Trx redox state. Phosphorylation of apoptosis signalling kinase 1 (ASK1), caspase-3 activity and the number of apoptotic cells were evaluated to investigate the induction of Trx-mediated apoptotic cell death. Additionally, primary cerebellar neurons from mice depleted of mitochondrial Grx2 (mGrx2D) were used to examine the link between Grx activity and Trx function. Results showed that Trx was affected at higher exposure levels than TrxR, especially for EtHg. GSH levels were only significantly affected by exposure to a high concentration of EtHg. Depletion of GSH with buthionine sulfoximine (BSO) severely increased Trx oxidation by Hg. Notably, EtHg-induced oxidation of Trx was significantly enhanced in primary neurons of mGrx2D mice. Our results suggest that GSH/Grx acts as backups for TrxR in neuronal cells to maintain Trx turnover during Hg exposure, thus linking different mechanisms of molecular and cellular toxicity. Finally, Trx oxidation by Hg compounds was associated to apoptotic hallmarks, including increased ASK-1 phosphorylation, caspase-3 activation and increased number of apoptotic cells

  4. Phenylbutyric acid rescues endoplasmic reticulum stress-induced suppression of APP proteolysis and prevents apoptosis in neuronal cells.

    Directory of Open Access Journals (Sweden)

    Jesse C Wiley

    Full Text Available BACKGROUND: The familial and sporadic forms of Alzheimer's disease (AD have an identical pathology with a severe disparity in the time of onset [1]. The pathological similarity suggests that epigenetic processes may phenocopy the Familial Alzheimer's disease (FAD mutations within sporadic AD. Numerous groups have demonstrated that FAD mutations in presenilin result in 'loss of function' of gamma-secretase mediated APP cleavage [2], [3], [4], [5]. Accordingly, ER stress is prominent within the pathologically impacted brain regions in AD patients [6] and is reported to inhibit APP trafficking through the secretory pathway [7], [8]. As the maturation of APP and the cleaving secretases requires trafficking through the secretory pathway [9], [10], [11], we hypothesized that ER stress may block trafficking requisite for normal levels of APP cleavage and that the small molecular chaperone 4-phenylbutyrate (PBA may rescue the proteolytic deficit. METHODOLOGY/PRINCIPAL FINDINGS: The APP-Gal4VP16/Gal4-reporter screen was stably incorporated into neuroblastoma cells in order to assay gamma-secretase mediated APP proteolysis under normal and pharmacologically induced ER stress conditions. Three unrelated pharmacological agents (tunicamycin, thapsigargin and brefeldin A all repressed APP proteolysis in parallel with activation of unfolded protein response (UPR signaling-a biochemical marker of ER stress. Co-treatment of the gamma-secretase reporter cells with PBA blocked the repressive effects of tunicamycin and thapsigargin upon APP proteolysis, UPR activation, and apoptosis. In unstressed cells, PBA stimulated gamma-secretase mediated cleavage of APP by 8-10 fold, in the absence of any significant effects upon amyloid production, by promoting APP trafficking through the secretory pathway and the stimulation of the non-pathogenic alpha/gamma-cleavage. CONCLUSIONS/SIGNIFICANCE: ER stress represses gamma-secretase mediated APP proteolysis, which replicates

  5. Metallothionein-I overexpression alters brain inflammation and stimulates brain repair in transgenic mice with astrocyte-targeted interleukin-6 expression

    DEFF Research Database (Denmark)

    Penkowa, Milena; Camats, Jordi; Giralt, Mercedes

    2003-01-01

    injury, such as a cryolesion, demonstrate a neuroprotective role of IL-6. Thus, the GFAP-IL-6 mice showed faster tissue repair and decreased oxidative stress and apoptosis compared with control litter-mate mice. The neuroprotective factors metallothionein-I+II (MT-I+II) were upregulated by the cryolesion...... the inflammatory response, decreased oxidative stress and apoptosis significantly, and increased brain tissue repair in comparison with either GFAP-IL-6 or control litter-mate mice. Overall, the results demonstrate that brain MT-I+II proteins are fundamental neuroprotective factors....

  6. Deletion of Metallothionein Exacerbates Intermittent Hypoxia-Induced Oxidative and Inflammatory Injury in Aorta

    Directory of Open Access Journals (Sweden)

    Shanshan Zhou

    2014-01-01

    Full Text Available The present study was to explore the effect of metallothionein (MT on intermittent hypoxia (IH induced aortic pathogenic changes. Markers of oxidative damages, inflammation, and vascular remodeling were observed by immunohistochemical staining after 3 days and 1, 3, and 8 weeks after IH exposures. Endogenous MT was induced after 3 days of IH but was significantly decreased after 8 weeks of IH. Compared with the wild-type mice, MT knock-out mice exhibited earlier and more severe pathogenic changes of oxidative damages, inflammatory responses, and cellular apoptosis, as indicated by the significant accumulation of collagen, increased levels of connective tissue growth factor, transforming growth factor β1, tumor necrosis factor-alpha, vascular cell adhesion molecule 1,3-nitrotyrosine, and 4-hydroxy-2-nonenal in the aorta. These findings suggested that chronic IH may lead to aortic damages characterized by oxidative stress and inflammation, and MT may play a pivotal role in the above pathogenesis process.

  7. Comparative population analysis of metallothionein promoter alleles suggests stress-induced microevolution in the field.

    NARCIS (Netherlands)

    Janssens, T.K.S.; Del Rio Lopez, R.; Mariën, A.G.H.; Timmermans, M.J.T.N.; Montagne-Wajer, K; van Straalen, N.M.; Roelofs, D.

    2008-01-01

    We investigate a model system for microevolution of transcriptional regulation: metallothionein expression in springtails. A previous survey of the metallothionein promoter in Orchesella cincta (Collembola) revealed nine alleles with differential basal activities and responses to cadmium and

  8. Comparative population analysis of metallothionein promoter alleles suggests stress-induced microevolution in the field

    NARCIS (Netherlands)

    Janssens, Thierry K S; Lopéz, Ricardo del Rio; Mariën, Janine; Timmermans, Martijn J T N; Montagne-Wajer, K; van Straalen, Nico M; Roelofs, Dick

    2008-01-01

    We investigate a model system for microevolution of transcriptional regulation: metallothionein expression in springtails. A previous survey of the metallothionein promoter in Orchesella cincta (Collembola) revealed nine alleles with differential basal activities and responses to cadmium and

  9. Anti-metallothionein IgG and levels of metallothionein in autistic children with GI disease

    Directory of Open Access Journals (Sweden)

    A J Russo

    2009-01-01

    Full Text Available A J RussoMount Saint Mary’s University, Emmitsburg, MD, USAAim: To assess both serum concentration of metallotionein (MT and anti-metallothionein (anti-MT immunoglobulin G (IgG in autistic children with gastrointestinal (GI symptoms and controls, and to test the hypothesis that there is an association between the presence of MT, anti-MT IgG, and inflammatory GI disease seen in many children with autistic spectrum disorder (ASD.Subjects and methods: ELISAs were used to measure serum MT and anti-MT IgG in 41 autistic children with chronic digestive disease (many with ileo-colonic lymphoid nodular hyperplasia [LNH] and inflammation of the colorectum, small bowel, and/or stomach, and 33 controls (17 age-matched autistic children with no GI disease and 16 age-matched children without autism or GI disease.Results: Ten of 41 autistic children with chronic digestive disease had high serum concentration of MT compared to only one of the 33 controls (p < 0.01. Thirteen of the 41 autistic children with chronic digestive disease had anti-MT IgG compared to only four of 33 controls (p < 0.01. Nine of 10 (90% of autistic children with GI disease with high MT levels had a regressive onset (compared to the expected 25 of 41, or 61%, in this group (p < 0.05, whereas only nine of 13 of the autistic children with GI disease and anti-MT IgG had a regressive onset (70% which was not significantly higher than the expected. We didn’t find any correlation between severity of GI disease and MT concentration or anti-MT IgG.Discussion: These results suggest a relationship between MT, anti-MT IgG and GI disease seen in many ASD individuals.Keywords: autism, metallothionein, anti-metallothionein, GI disease

  10. The effect of chronic stimulation of serotonin receptor type 7 on recognition, passive avoidance memory, hippocampal long-term potentiation, and neuronal apoptosis in the amyloid β protein treated rat.

    Science.gov (United States)

    Shahidi, Siamak; Asl, Sara Soleimani; Komaki, Alireza; Hashemi-Firouzi, Nasrin

    2018-05-01

    Alzheimer's disease (AD) is a neurodegenerative disorder characterized by memory impairment, neuronal death, and synaptic loss in the hippocampus. Long-term potentiation (LTP), a type of synaptic plasticity, occurs during learning and memory. Serotonin receptor type 7 (5-HTR7) activation is suggested as a possible therapeutic target for AD. The aim of the present study was to examine the effects of chronic treatment with the 5-HTR7 agonist, AS19, on cognitive function, memory, hippocampal plasticity, amyloid beta (Aβ) plaque accumulation, and apoptosis in an adult rat model of AD. AD was induced in rats using Aβ (single 1 μg/μL intracerebroventricular (icv) injection during surgery). The following experimental groups were included: control, sham-operated, Aβ + saline (1 μL icv for 30 days), and Aβ + AS19 (1 μg/μL icv for 30 days) groups. The animals were tested for cognition and memory performance using the novel object recognition and passive avoidance tests, respectively. Next, anesthetized rats were placed in a stereotaxic apparatus for electrode implantation, and field potentials were recorded in the hippocampal dentate gyrus. Lastly, brains were removed and Aβ plaques and neuronal apoptosis were evaluated using Congo red staining and TUNEL assay, respectively. Administration of AS19 in the Aβ rats increased the discrimination index of the novel object recognition test. Furthermore, AS19 treatment decreased time spent in the dark compartment during the passive avoidance test. AS19 also enhanced both the population spike (PS) amplitude and the field excitatory postsynaptic potential (fEPSP) slope evoked potentials of the LTP components. Aβ plaques and neuronal apoptosis were decreased in the AS19-treated Aβ rats. These results indicate that chronic treatment with a 5-HTR7 agonist can prevent Aβ-related impairments in cognition and memory performance by alleviating Aβ plaque accumulation and neuronal apoptosis, hence improving neuronal

  11. METALLOTHIONEIN: CLASSIFICATION, BIOCHEMICAL FEATURES AND CLINICAL APPLICATIONS

    Directory of Open Access Journals (Sweden)

    Tooba Naz Shamsi

    2014-03-01

    Full Text Available Metallothionein (MT is a ubiquitous low molecular weight protein with high cysteine content and has strong affinity for heavy metals. MT provides protection against heavy metal toxicity, oxidative stress, and participates in the regulation of physiological metals like zinc (Zn2+ and copper (Cu. Abnormal MT expression and function presumably leads to various diseases like diabetes, cancer and neuro-degenerative diseases. MT gene expression is induced by a high variety of stimuli like metal exposure, oxidative stress, glucocorticoids, hydric stress etc. The level of the response to these inducers depends on the MT gene. These activities are regulated through intracellular metal ion modulation and free radical scavenging. MT participates in the uptake, transport, and regulation of zinc in biological system. It regulates zinc homeostasis by binding and releasing zinc ions which are a key element for the activation and binding of certain transcription factors through its participation in the zinc finger region of the protein. It also seems to be important for the regulation of tumor suppressor protein, p 53. Because MT plays an important role in transcription factor regulation, problems with MT function or expression may lead to malignant transformation of cells and ultimately cancer. There are variou

  12. Metallothioneins: Emerging Modulators in Immunity and Infection

    Directory of Open Access Journals (Sweden)

    Kavitha Subramanian Vignesh

    2017-10-01

    Full Text Available Metallothioneins (MTs are a family of metal-binding proteins virtually expressed in all organisms including prokaryotes, lower eukaryotes, invertebrates and mammals. These proteins regulate homeostasis of zinc (Zn and copper (Cu, mitigate heavy metal poisoning, and alleviate superoxide stress. In recent years, MTs have emerged as an important, yet largely underappreciated, component of the immune system. Innate and adaptive immune cells regulate MTs in response to stress stimuli, cytokine signals and microbial challenge. Modulation of MTs in these cells in turn regulates metal ion release, transport and distribution, cellular redox status, enzyme function and cell signaling. While it is well established that the host strictly regulates availability of metal ions during microbial pathogenesis, we are only recently beginning to unravel the interplay between metal-regulatory pathways and immunological defenses. In this perspective, investigation of mechanisms that leverage the potential of MTs to orchestrate inflammatory responses and antimicrobial defenses has gained momentum. The purpose of this review, therefore, is to illumine the role of MTs in immune regulation. We discuss the mechanisms of MT induction and signaling in immune cells and explore the therapeutic potential of the MT-Zn axis in bolstering immune defenses against pathogens.

  13. Effects of microRNA-129 and its target gene c-Fos on proliferation and apoptosis of hippocampal neurons in rats with epilepsy via the MAPK signaling pathway.

    Science.gov (United States)

    Wu, Dong-Mei; Zhang, Yu-Tong; Lu, Jun; Zheng, Yuan-Lin

    2018-09-01

    This study aims to investigate the effect of microRNA-129 (miR-129) on proliferation and apoptosis of hippocampal neurons in epilepsy rats by targeting c-Fos via the MAPK signaling pathway. Thirty rats were equally classified into a model group (successfully established as chronic epilepsy models) and a normal group. Expression of miR-129, c-Fos, bax, and MAPK was detected by RT-qPCR and Western blotting. Hippocampal neurons were assigned into normal, blank, negative control (NC), miR-129 mimic, miR-129 inhibitor, siRNA-c-Fos, miR-129 inhibitor+siRNA-c-Fos groups. The targeting relationship between miR-129 and c-Fos was predicted and verified by bioinformatics websites and dual-luciferase reporter gene assay. Cell proliferation after transfection was measured by MTT assay, and cell cycle and apoptosis by flow cytometry. c-Fos is a potential target gene of miR-129. Compared with the normal group, the other six groups showed a decreased miR-129 expression; increased expression of expression of c-Fos, Bax, and MAPK; decreased proliferation; accelerated apoptosis; more cells arrested in the G1 phase; and fewer cells arrested in the S phase. Compared with the blank and NC groups, the miR-129 mimic group and the siRNA-c-Fos group showed decreased expression of c-Fos, Bax, and MAPK, increased cells proliferation, and decreased cell apoptosis, fewer cells arrested in the G1 phase and more cells arrested in the S phase. However, the miR-129 inhibitor groups showed reverse consequences. This study suggests that miR-129 could inhibit the occurrence and development of epilepsy by repressing c-Fos expression through inhibiting the MAPK signaling pathway. © 2017 Wiley Periodicals, Inc.

  14. Metallothioneins in human tumors and potential roles in carcinogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Cherian, M. George; Jayasurya, A.; Bay, Boon-Huat

    2003-12-10

    Metallothioneins (MT) are a group of low-molecular weight, cysteine rich intracellular proteins, which are encoded by a family of genes containing at least 10 functional isoforms in human. The expression and induction of these proteins have been associated with protection against DNA damage, oxidative stress and apoptosis. Moreover, MT may potentially activate certain transcriptional factors by donating zinc. Although MT is a cytosolic protein in resting cells, it can be translocated transiently to the cell nucleus during cell proliferation and differentiation. A number of studies have shown an increased expression of MT in various human tumors of the breast, colon, kidney, liver, lung, nasopharynx, ovary, prostate, salivary gland, testes, thyroid and urinary bladder. However, MT is down-regulated in certain tumors such as hepatocellular carcinoma and liver adenocarcinoma. Hence, the expression of MT is not universal to all human tumors, but may depend on the differentiation status and proliferative index of tumors, along with other tissue factors and gene mutations. In certain tumors such as germ cell carcinoma, the expression of MT is closely related to the tumor grade and proliferative activity. Increased expression of MT has also been observed in less differentiated tumors. Thus, expression of MT may be a potential prognostic marker for certain tumors. There are few reports on the expression of the different isoforms of MT which have been analyzed by specific gene probes. They reveal that certain isoforms are expressed in specific cell types. The factors which can influence MT induction in human tumors are not yet understood. Down-regulation of MT synthesis in hepatic tumors may be related to hypermethylation of the MT-promoter or mutation of other genes such as the p53 tumor suppressor gene. In vitro studies using human cancer cells suggest a possible role for p53 and the estrogen-receptor on the expression and induction of MT in epithelial neoplastic cells

  15. Metallothioneins in human tumors and potential roles in carcinogenesis

    International Nuclear Information System (INIS)

    Cherian, M. George; Jayasurya, A.; Bay, Boon-Huat

    2003-01-01

    Metallothioneins (MT) are a group of low-molecular weight, cysteine rich intracellular proteins, which are encoded by a family of genes containing at least 10 functional isoforms in human. The expression and induction of these proteins have been associated with protection against DNA damage, oxidative stress and apoptosis. Moreover, MT may potentially activate certain transcriptional factors by donating zinc. Although MT is a cytosolic protein in resting cells, it can be translocated transiently to the cell nucleus during cell proliferation and differentiation. A number of studies have shown an increased expression of MT in various human tumors of the breast, colon, kidney, liver, lung, nasopharynx, ovary, prostate, salivary gland, testes, thyroid and urinary bladder. However, MT is down-regulated in certain tumors such as hepatocellular carcinoma and liver adenocarcinoma. Hence, the expression of MT is not universal to all human tumors, but may depend on the differentiation status and proliferative index of tumors, along with other tissue factors and gene mutations. In certain tumors such as germ cell carcinoma, the expression of MT is closely related to the tumor grade and proliferative activity. Increased expression of MT has also been observed in less differentiated tumors. Thus, expression of MT may be a potential prognostic marker for certain tumors. There are few reports on the expression of the different isoforms of MT which have been analyzed by specific gene probes. They reveal that certain isoforms are expressed in specific cell types. The factors which can influence MT induction in human tumors are not yet understood. Down-regulation of MT synthesis in hepatic tumors may be related to hypermethylation of the MT-promoter or mutation of other genes such as the p53 tumor suppressor gene. In vitro studies using human cancer cells suggest a possible role for p53 and the estrogen-receptor on the expression and induction of MT in epithelial neoplastic cells

  16. Metallothionein induction: a measure of radioprotective action

    Energy Technology Data Exchange (ETDEWEB)

    Matsubara, J.

    1988-08-01

    Mice treated to induce metallothionein (MT) synthesis in the liver prior to irradiation were resistant to radiation; this also was true of mice that had a portion of skin surgically removed or an immunomodulator administered. Mice given Mn, Cd or Zn subcutaneously prior to irradiation showed increased tolerance to an LD50 level (6-8 Gy) of x rays compared with controls that received no pretreatments (p less than 0.01). All the mice were evaluated during a 30-d postirradiation period. Weight loss in control mice peaked two weeks after irradiation, whereas body weight in mice pretreated with Mn continued to increase after irradiation with x rays. The normal level of MT in mouse liver (25 micrograms g-1 tissue) increased to 70 micrograms g-1 liver tissue in mice irradiated with 6.3-Gy x rays. However, following subcutaneous injection of Cd, Mn or Zn, or intraperitoneal injection of OK-432 (Picibanil, a killed streptococcal preparation, MT levels in liver increased by a factor of 2-8 compared to irradiated that were not treated with the reagents listed above. The mortality rate of mice with a surgically excised 2 X 2-cm2 portion of dorsal skin or of those administered OK-432 was lower than that of controls, and MT levels in liver (150-400 micrograms g-1 tissue) were higher than those of irradiated mice that were not surgically treated. These results suggest that the body's protective action against radiation correlates with the biosynthesis of MT, or that MT acts as a scavenger of radiation-induced peroxides.

  17. Metallothionein induction: a measure of radioprotective action

    International Nuclear Information System (INIS)

    Matsubara, J.

    1988-01-01

    Mice treated to induce metallothionein (MT) synthesis in the liver prior to irradiation were resistant to radiation; this also was true of mice that had a portion of skin surgically removed or an immunomodulator administered. Mice given Mn, Cd or Zn subcutaneously prior to irradiation showed increased tolerance to an LD50 level (6-8 Gy) of x rays compared with controls that received no pretreatments (p less than 0.01). All the mice were evaluated during a 30-d postirradiation period. Weight loss in control mice peaked two weeks after irradiation, whereas body weight in mice pretreated with Mn continued to increase after irradiation with x rays. The normal level of MT in mouse liver (25 micrograms g-1 tissue) increased to 70 micrograms g-1 liver tissue in mice irradiated with 6.3-Gy x rays. However, following subcutaneous injection of Cd, Mn or Zn, or intraperitoneal injection of OK-432 (Picibanil, a killed streptococcal preparation, MT levels in liver increased by a factor of 2-8 compared to irradiated that were not treated with the reagents listed above. The mortality rate of mice with a surgically excised 2 X 2-cm2 portion of dorsal skin or of those administered OK-432 was lower than that of controls, and MT levels in liver (150-400 micrograms g-1 tissue) were higher than those of irradiated mice that were not surgically treated. These results suggest that the body's protective action against radiation correlates with the biosynthesis of MT, or that MT acts as a scavenger of radiation-induced peroxides

  18. Regulation of tissue levels of metallothionein with emphasis on metallothionein degradation

    International Nuclear Information System (INIS)

    Chen, M.L.

    1988-01-01

    The synthesis and degradation of metallothionein (MT) was studied in streptozotocin-induced diabetic rats and monolayer cultures of adult rat hepatocytes. Critical analysis of in vivo studies with diabetic rats and other literature revealed that cytoplasmic turnover of MT may not reflect actual degradation of this protein. Therefore, the characteristics of MT degradation in primary cultures of hepatocytes were investigated in subsequent studies. Hepatocytes were incubated in medium containing 35 S-cysteine and 100 μM Zn overnight to induce MT synthesis. The level of 35 S-MT was quantified in heat stable extracts of cell homogenates by Fast Protein Liquid Chromatography (FPLC). When Zn was removed from medium, the rate of 35 S-MT turnover was found times faster than general 3 H-protein. This decrease in cellular MT level reflected degradation since less than 1% of cellular MT was secreted. The rate of MT degradation was inversely proportional to cellular Zn status

  19. Metallothioneins I and II: neuroprotective significance during CNS pathology

    DEFF Research Database (Denmark)

    Penkowa, Milena; Stankovic, Roger; Chung, Roger

    2006-01-01

    Metallothioneins (MTs) constitutes a superfamily of highly conserved, low molecular weight polypeptides, which are characterized by high contents of cysteine (sulphur) and metals. As intracellular metal-binding proteins they play a significant role in the regulation of essential metals. The major...

  20. Purple sweet potato color alleviates D-galactose-induced brain aging in old mice by promoting survival of neurons via PI3K pathway and inhibiting cytochrome C-mediated apoptosis.

    Science.gov (United States)

    Lu, Jun; Wu, Dong-mei; Zheng, Yuan-lin; Hu, Bin; Zhang, Zi-feng

    2010-05-01

    Purple sweet potato color (PSPC), a class of naturally occurring anthocyanins, protects brain function against oxidative stress induced by D-galactose (D-gal) (Sigma-Aldrich, St. Louis, MO, USA). Our data showed that PSPC enhanced open-field activity, decreased step-through latency, and improved spatial learning and memory ability in D-gal-treated old mice by decreasing advanced glycation end-products' (AGEs) formation and the AGE receptor (RAGE) expression, and by elevating Cu,Zn-superoxide dismutase (Cu,Zn-SOD) (Sigma-Aldrich) and catalase (CAT) expression and activity. Cleavage of caspase-3 and increased terminal deoxynucleotidyl transferase (TdT)-mediated deoxyuridine triphosphate (dUTP) nick-end-labeling (TUNEL)-positive cells in D-gal-treated old mice were inhibited by PSPC, which might be attributed to its antioxidant property. PSPC also suppressed the activation of c-Jun NH(2)-terminal kinase (JNK) and the release of cytochrome c from mitochondria that counteracted the onset of neuronal apoptosis in D-gal-treated old mice. Furthermore, it was demonstrated that phosphoinositide 3-kinase (PI3K) activation was required for PSPC to promote the neuronal survival accompanied with phosphorylation and activation of Akt and p44/42 mitogen-activated protein kinase (MAPK) by using PI3K inhibitor LY294002 (Cell Signaling Technology, Inc., Beverly, MA, USA), implicating a neuronal survival mechanism. The present results suggest that neuronal survival promoted by PSPC may be a potentially effective method to enhance resistance of neurons to age-related disease.

  1. CNS wound healing is severely depressed in metallothionein I- and II-deficient mice

    DEFF Research Database (Denmark)

    Penkowa, M; Carrasco, J; Giralt, M

    1999-01-01

    . In contrast to normal mice, at 20 dpl no wound healing had occurred. The rate of apoptosis, as determined by using terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling, was drastically increased in neurons of ipsilateral cortex of the MT-I+II null mice. Our results demonstrate that MT...

  2. Lycium barbarum polysaccharide protects against oxygen glucose deprivation/reoxygenation-induced apoptosis and autophagic cell death via the PI3K/Akt/mTOR signaling pathway in primary cultured hippocampal neurons.

    Science.gov (United States)

    Yu, Yang; Wu, Xiuquan; Pu, Jingnan; Luo, Peng; Ma, Wenke; Wang, Jiu; Wei, Jialiang; Wang, Yuanxin; Fei, Zhou

    2018-01-01

    Lycium barbarum polysaccharide (LBP) is the main active ingredient of Lycium barbarum, which exhibits several beneficial effects, including neuroprotection, anti-aging and anti-oxidation. However, the mechanism by which LBP protects against cerebral ischemia/reperfusion-induced injury remains obscure. In this study, we found that LBP pretreatment greatly attenuated oxygen glucose deprivation/reperfusion (OGD/R) injury in primary cultured hippocampal neurons. LBP also suppressed OGD/R-induced lactate dehydrogenase (LDH) leakage, and ameliorated oxidative stress. In addition, LBP significantly reduced OGD/R-induced apoptosis and autophagic cell death. LBP caused the down-regulation of cleaved Caspase-3/Caspase-3, LC3II/LC3I and Beclin 1, as well as up-regulation of Bcl-2/Bax and p62. Furthermore, mechanistic studies indicated that LBP pretreatment increased p-Akt and p-mTOR levels after OGD/R. In summary, our results indicated that LBP protects against OGD/R-induced neuronal injury in primary hippocampal neurons by activating the PI3K/Akt/mTOR signaling pathway. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. The mechanism of long non-coding RNA MEG3 for neurons apoptosis caused by hypoxia: mediated by miR-181b-12/15-LOX signaling pathway

    Directory of Open Access Journals (Sweden)

    Xiaomin Liu

    2016-09-01

    Full Text Available Objective: lncRNAs are recently thought to play a significant role in cellular homeostasis during pathological process of diseases by competing inhibiting miRNA function. The aim of present study was to assess the function of long non-coding RNA (lncRNA MEG3 and its functional interaction with microRNA-181b in cerebral ischemic infarct of mice and hypoxia-induced neurons apoptosis. Methods: To address this question, we performed the experiments with in vivo middle cerebral artery occlusion (MCAO mice model and in vitro oxygen-glucose deprivation (OGD-cultured neuronal HT22 cell line. Relative expression of MEG3, miR-181b and 12/15-LOX (lipoxygenase mRNA was determined using quantitative RT-PCR. Western blot was used to evaluate 12/15-LOX protein expression. TUNEL assay was performed to assess cell apoptosis.Results: In both MCAO mice and OGD-cultured HT22 cell, ischemia or hypoxia treatment results in a time-dependent increase in MEG3 and 12/15-LOX expression and decrease in miR-181b expression. Knockdown of MEG3 contributes to attenuation of hypoxia-induced apoptosis of HT22 cell. Also, expression level of MEG3 negatively correlated with miR-181b expression and positively correlated with 12/15-LOX expression. In contrary to MEG3, miR-181b overexpression attenuated hypoxia-induced HT22 cell apoptosis, as well as suppressed hypoxia-induced increase in 12/15-LOX expression. By luciferase reporter assay, we concluded that miR-181b directly binds to 12/15-LOX 3’-UTR, thereby negatively regulates 12/15-LOX expression. Conclusion: Our data suggested that long non-coding RNA MEG3 functions as a competing endogenous RNA for miR-181b to regulate 12/15-LOX expression in middle cerebral artery occlusion-induced ischemic infarct of brain nerve cells.

  4. Differential expression of metallothioneins in the CNS of mice with experimental autoimmune encephalomyelitis

    DEFF Research Database (Denmark)

    Espejo, C; Carrasco, J; Hidalgo, J

    2001-01-01

    Multiple sclerosis is an inflammatory, demyelinating disease of the CNS. Metallothioneins-I+II are antioxidant proteins induced in the CNS by immobilisation stress, trauma or degenerative diseases which have been postulated to play a neuroprotective role, while the CNS isoform metallothionein......-III has been related to Alzheimer's disease. We have analysed metallothioneins-I-III expression in the CNS of mice with experimental autoimmune encephalomyelitis. Moreover, we have examined the putative role of interferon-gamma, a pro-inflammatory cytokine, in the control of metallothioneins expression...

  5. Metallothionein in brook trout (salvelinus fontinalis) as a biological indicator of inorganic chemical contaminant stress

    International Nuclear Information System (INIS)

    Hamilton, S.J.

    1985-01-01

    A technique for quantifying metallothionein was evaluated with fish tissue. Adult brook trout were administered 3 mg 109 cadmium/kg body weight by intraperitoneal injection over a 5 day period to induce metallothionein concentrations in liver and kidney tissues. The method was modified so cadmium bound to unsaturated metallothionein could be measured. The method gave precise measurements and was used to evaluate the toxicological significant of metallothionein in two 30-day chronic toxicity studies of cadmium on brook trout. In particular, metallothionein was evaluated as a biological indicator of inorganic chemical stress in brook trout. Pathological effects in animals resulting from exposure to inorganic chemicals is thought to occur when metallothionein's sequestering ability is exceeded; a phenomenon explained by the spillover hypothesis. The presence of free cadmium in tissues of fish from all exposures suggests metallothionein was not saturated with cadmium perhaps because of competition for binding sites on metallothionein between cadmium and other inorganic chemicals such as copper and zinc. Based on results of the two toxicity studies, the spillover hypothesis should be redefined to a continuum of toxic responses to varying balances between the relative abundance of inorganic chemicals present and their respective binding affinities for metallothionein

  6. The retrograde delivery of adenovirus vector carrying the gene for brain-derived neurotrophic factor protects neurons and oligodendrocytes from apoptosis in the chronically compressed spinal cord of twy/twy mice.

    Science.gov (United States)

    Uchida, Kenzo; Nakajima, Hideaki; Hirai, Takayuki; Yayama, Takafumi; Chen, Kebing; Guerrero, Alexander Rodriguez; Johnson, William Eustace; Baba, Hisatoshi

    2012-12-15

    The twy/twy mouse undergoes spontaneous chronic mechanical compression of the spinal cord; this in vivo model system was used to examine the effects of retrograde adenovirus (adenoviral vector [AdV])-mediated brain-derived neurotrophic factor (BDNF) gene delivery to spinal neural cells. To investigate the targeting and potential neuroprotective effect of retrograde AdV-mediated BDNF gene transfection in the chronically compressed spinal cord in terms of prevention of apoptosis of neurons and oligodendrocytes. Several studies have investigated the neuroprotective effects of neurotrophins, including BDNF, in spinal cord injury. However, no report has described the effects of retrograde neurotrophic factor gene delivery in compressed spinal cords, including gene targeting and the potential to prevent neural cell apoptosis. AdV-BDNF or AdV-LacZ (as a control gene) was injected into the bilateral sternomastoid muscles of 18-week old twy/twy mice for retrograde gene delivery via the spinal accessory motor neurons. Heterozygous Institute of Cancer Research mice (+/twy), which do not undergo spontaneous spinal compression, were used as a control for the effects of such compression on gene delivery. The localization and cell specificity of β-galactosidase expression (produced by LacZ gene transfection) and BDNF expression in the spinal cord were examined by coimmunofluorescence staining for neural cell markers (NeuN, neurons; reactive immunology protein, oligodendrocytes; glial fibrillary acidic protein, astrocytes; OX-42, microglia) 4 weeks after gene injection. The possible neuroprotection afforded by retrograde AdV-BDNF gene delivery versus AdV-LacZ-transfected control mice was assessed by scoring the prevalence of apoptotic cells (terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling-positive cells) and immunoreactivity to active caspases -3, -8, and -9, p75, neurofilament 200 kD (NF), and for the oligodendroglial progenitor marker, NG2. RESULTS

  7. Review on methods for determination of metallothioneins in aquatic organisms.

    Science.gov (United States)

    Shariati, Fatemeh; Shariati, Shahab

    2011-06-01

    One aspect of environmental degradation in coastal areas is pollution from toxic metals, which are persistent and are bioaccumulated by marine organisms, with serious public health implications. A conventional monitoring system of environmental metal pollution includes measuring the level of selected metals in the whole organism or in respective organs. However, measuring only the metal content in particular organs does not give information about its effect at the subcellular level. Therefore, the evaluation of biochemical biomarker metallothionein may be useful in assessing metal exposure and the prediction of potential detrimental effects induced by metal contamination. There are some methods for the determination of metallothioneins including spectrophotometric method, electrochemical methods, chromatography, saturation-based methods, immunological methods, electrophoresis, and RT-PCR. In this paper, different methods are discussed briefly and the comparison between them will be presented.

  8. Metallothionein as biomarker of mussel exposure to heavy metals

    International Nuclear Information System (INIS)

    Raspor, B.; Erk, M.; Pavicic, J.; Juric, D.; Kwokal, Z.; Odzak, N.

    1999-01-01

    The biological effect of marine pollution with heavy metals is followed in bivalves by means of the induced amount of metallothioneins (MTs), determined in different tissue types. The biological effect of the available toxic metals, cadmium and mercury, are related to the amount of MTs in the whole edible part, gills and the digestive gland of Mytilus galloprovincialis. For that purpose highly sensitive chemical and biochemical methods for metal and metallothionein content determination were developed and applied. The study was conducted in the Kastela Bay, which is the urban and industrial center of Dalmatia, Croatia, with two groups of mussels, indigenous and the transplanted. In accordance with the objective of the Symposium the results on monitoring the marine pollution by means of MTs as a biomarker, isolated from the edible, sessile and filter-feeding bivalves are discussed. (author)

  9. Exercise-induced metallothionein expression in human skeletal muscle fibres

    DEFF Research Database (Denmark)

    Penkowa, Milena; Keller, Pernille; Keller, Charlotte

    2005-01-01

    in both type I and II muscle fibres. This is the first report demonstrating that MT-I + II are significantly induced in human skeletal muscle fibres following exercise. As MT-I + II are antioxidant factors that protect various tissues during pathological conditions, the MT-I + II increases post exercise......Exercise induces free oxygen radicals that cause oxidative stress, and metallothioneins (MTs) are increased in states of oxidative stress and possess anti-apoptotic effects. We therefore studied expression of the antioxidant factors metallothionein I and II (MT-I + II) in muscle biopsies obtained...... in response to 3 h of bicycle exercise performed by healthy men and in resting controls. Both MT-I + II proteins and MT-II mRNA expression increased significantly in both type I and II muscle fibres after exercise. Moreover, 24 h after exercise the levels of MT-II mRNA and MT-I + II proteins were still highly...

  10. The loss of the kinases SadA and SadB results in early neuronal apoptosis and a reduced number of progenitors.

    Science.gov (United States)

    Dhumale, Pratibha; Menon, Sindhu; Chiang, Joanna; Püschel, Andreas W

    2018-01-01

    The neurons that form the mammalian neocortex originate from progenitor cells in the ventricular (VZ) and subventricular zone (SVZ). Newborn neurons are multipolar but become bipolar during their migration from the germinal layers to the cortical plate (CP) by forming a leading process and an axon that extends in the intermediate zone (IZ). Once they settle in the CP, neurons assume a highly polarized morphology with a single axon and multiple dendrites. The AMPK-related kinases SadA and SadB are intrinsic factors that are essential for axon formation during neuronal development downstream of Lkb1. The knockout of both genes encoding Sad kinases (Sada and Sadb) results not only in a loss of axons but also a decrease in the size of the cortical plate. The defect in axon formation has been linked to a function of Sad kinases in the regulation of microtubule binding proteins. However, the causes for the reduced size of the cortical plate in the Sada-/-;Sadb-/- knockout remain to be analyzed in detail. Here we show that neuronal cell death is increased and the number of neural progenitors is decreased in the Sada-/-;Sadb-/- CP. The reduced number of progenitors is a non-cell autonomous defect since they do not express Sad kinases. These defects are restricted to the neocortex while the hippocampus remains unaffected.

  11. Metallothionein expression in chloroplasts enhances mercury accumulation and phytoremediation capability

    OpenAIRE

    Ruiz, Oscar N.; Alvarez, Derry; Torres, Cesar; Roman, Laura; Daniell, Henry

    2011-01-01

    Genetic engineering to enhance mercury phytoremediation has been accomplished by expression of the merAB genes that protects the cell by converting Hg[II] into Hg[0] which volatilizes from the cell. A drawback of this approach is that toxic Hg is released back into the environment. A better phytoremediation strategy would be to accumulate mercury inside plants for subsequent retrieval. We report here the development of a transplastomic approach to express the mouse metallothionein gene (mt1) ...

  12. Urinary metallothionein as a biological indicator of occupational cadmium exposure

    International Nuclear Information System (INIS)

    Tohyama, C.; Shaikh, Z.A.; Ellis, K.J.; Cohn, S.H.

    1981-01-01

    Radioimmunoassay and neutron activation data indicate that the urinary metallothionein concentration is related to the liver Cd concentration in occupational Cd exposure. It is also related to the kidney Cd content - but only before the onset of renal dysfunction. Further epidemiological studies are needed to establish a dose-response relationship, which may be useful in minimizing the hazard of Cd-induced renal dysfunction

  13. Metallothionein, a marker of antiapoptosis, is associated with clinical forms of oral lichen planus.

    Science.gov (United States)

    Allon, Irit; Ofir, Merav; Vered, Hanna; Hirshberg, Abraham

    2014-11-01

    To investigate the expression of anti- and proapoptosis markers, metallothionein (MT), and caspase-2, in the epithelial and inflammatory cells of oral lichen planus (OLP) patients, and to investigate the association with clinical parameters. Included were biopsies of 70 OLP patients. The clinical data were collected from patients' charts. The expression of MT and caspase-2 was immunomorphometrically analyzed in the epithelial and inflammatory cells, and the results were correlated with the clinical presentation. The epithelial and inflammatory cells expressed MT (10.2 ± 5.75 and 0.68 ± 0.86) and caspase-2 (1.54 ± 2.6 and 0.98 ± 1.15) which show a trend toward an inverse expression. The expression of MT in the epithelium was significantly higher in patients presenting with keratotic lichen planus than in patients with the atrophic and erosive forms (P = 0.0008). In the inflammatory cells, the expression of MT was inversely correlated with increasing age (R = 0.34, P = 0.0069). The pattern of expression of MT and caspase-2 in OLP suggests an extensive antiapoptotic response in the keratotic form of the disease. Symptomatic patients may benefit from therapy targeted to apoptosis in the future. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  14. Interleukin 6 regulates metallothionein gene expression and zinc metabolism in hepatocyte monolayer cultures

    International Nuclear Information System (INIS)

    Schroeder, J.J.; Cousins, R.J.

    1990-01-01

    Attention has focused on the cytokine interleukin 6 (IL-6) as a major mediator of acute-phase protein synthesis in hepatocytes in response to infection and tissue injury. The authors have evaluated the effects of IL-6 and IL-1α as well as extracellular zinc and glucocorticoid hormone on metal-lothionein gene expression and cellular zinc accumulation in rat hepatocyte monolayer cultures. Further, they have evaluated the teleological basis for cytokine mediation by examining cyto-protection from CCl 4 -induced damage. Incubation of hepatocytes with IL-6 led to concentration-dependent and time-dependent increases in metallothionein-1 and -2 mRNA and metallothionein protein. The level of each was increased within 3 hr after the addition of IL-6 at 10 ng/ml. Maximal increases the metallothionein mRNA and metallothionein protein were achieved after 12 hr and 36 hr, respectively. Concomitant with the up-regulation of metallothionein gene expression, IL-6 also increased cellular zinc. Responses to IL-6 required the synthetic glucocorticoid hormone dexamethasone and were optimized by increased extracellular zinc. Thus, IL-6 is a major cytokine mediator of metallothionein gene expression and zinc metabolism in hepatocytes and provides cytoprotection from CCl 4 -induced hepatotoxicity via a mode consistent with dependence upon increased cellular metallothionein synthesis and zinc accumulation

  15. [Effects of Naomaitong combined with mobilization of bone marrow mesenchymal stem cells on neuron apoptosis and expressions of Fas, FasL and caspase-3 proteins in rats with cerebral ischemia].

    Science.gov (United States)

    Li, Jian-sheng; Liu, Jing-xia; Tian, Yu-shou; Ren, Wei-hong; Zhang, Xin-feng; Wang, Ding-chao

    2009-09-01

    To observe the effects of Naomaitong, a compound traditional Chinese herbal medicine, combined with mobilization of bone marrow mesenchymal stem cells (BMSCs) on neuron apoptosis in rats with cerebral ischemia, and to explore the possible mechanism by detecting the expressions of Fas, FasL and caspase-3 proteins. Two hundred and two SD rats were divided into sham-operated group, untreated group, recombinant granulocyte colony-stimulating factor (rG-CSF) group, Naomaitong group and Naomaitong plus rG-CSF group (combination group). Focal cerebral ischemia was induced by intraluminal middle cerebral artery occlusion using a nylon thread with some modification. Rats in the rG-CSF group and the untreated group were administered with rG-CSF 10 microg/(kg x d) by subcutaneous injection 3 d before and 2 d after the operation respectively, once a day, and rats in the Naomaitong group and the combination group were intragastrically administered Naomaitong before and after the operation until sacrificed. Two, three, seven and fourteen days after operation, count of CD34-positive cells in peripheral blood and CD34 expression in brain tissue were determined. General neural function score (GNFS) was evaluated. Neuron apoptosis, expressions of Fas, FasL and caspase-3 in rat's brain were all measured. Count of CD34-positive cells in peripheral blood and CD34 expression in brain tissue were high in the untreated group, and reached the peak at 3 d and 7 d respectively. CD34 expression in brain tissue was increased in each treated group, especially in the combination group. GNFS was increased at 3 d and 7 d in the untreated group, 7 d and 14 d in the rG-CSF group and the combination group. Expressions of Fas, FasL and caspase-3 were increased 2, 3 and 7 d after operation, while expression of FasL at 2 d in the rG-CSF group, expressions of Fas, FasL and caspase-3 in the combination group were decreased. Expressions of Fas, FasL and caspase-3 at 7 d and 14 d in the combination group

  16. Lack of Prenylated Proteins, Autophagy Impairment and Apoptosis in SH-SY5Y Neuronal Cell Model of Mevalonate Kinase Deficiency

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    Paola Maura Tricarico

    2017-03-01

    Full Text Available Background/Aims: Mevalonate Kinase Deficiency (MKD, is a hereditary disease due to mutations in mevalonate kinase gene (MVK. MKD has heterogeneous clinical phenotypes: the correlation between MVK mutations and MKD clinical phenotype is still to be fully elucidated. Deficiency of prenylated proteins has been hypothesized as possible MKD pathogenic mechanism. Based on this hypothesis and considering that neurologic impairment characterizes Mevalonic Aciduria (MA, the most severe form of MKD, we studied the effects of I268T and N301T MVK mutations on protein prenylation, autophagy and programmed cell death in SH-SY5Y neuroblastoma cell lines. Methods: SH-SY5Y cells were transiently transfected, with the pCMV-6 plasmid containing MVK wild type and the two mutated sequences. Protein prenylation levels were evaluated using GFP-RhoA-F to assess farnesylation, and GFP-RhoA to evaluate geranylgeranylation; autophagy was measured by evaluating LC3 and p62 protein levels, while Annexin V-FITC and Propidium Iodide staining allowed apoptosis detection. Results: MVK mutants’ over-expression causes decreased levels of farnesylation and geranylgeranylation, and also increased LC3 lipidation in SH-SY5Y, with concomitant p62 accumulation. Treatment with bafilomycin A1 (an inhibitor of vacuolar H+-ATPase, a late autophagy inhibitor further increase LC3-II and p62 levels, suggesting that degradation of autophagolysosome could be impaired. SH-SY5Y, with both MVK mutants, showed apoptosis increase; the presence of N301T associated with augmented cell death. Conclusions: We hypothesize that mevalonate pathway impairment causes alteration of farnesylation and geranylgeranylation proteins and alteration of the autophagic flux; these changes can induce apoptosis, possibly more relevant in the presence of N301T mutation.

  17. Lack of Prenylated Proteins, Autophagy Impairment and Apoptosis in SH-SY5Y Neuronal Cell Model of Mevalonate Kinase Deficiency.

    Science.gov (United States)

    Tricarico, Paola Maura; Romeo, Alessandra; Gratton, Rossella; Crovella, Sergio; Celsi, Fulvio

    2017-01-01

    Mevalonate Kinase Deficiency (MKD), is a hereditary disease due to mutations in mevalonate kinase gene (MVK). MKD has heterogeneous clinical phenotypes: the correlation between MVK mutations and MKD clinical phenotype is still to be fully elucidated. Deficiency of prenylated proteins has been hypothesized as possible MKD pathogenic mechanism. Based on this hypothesis and considering that neurologic impairment characterizes Mevalonic Aciduria (MA), the most severe form of MKD, we studied the effects of I268T and N301T MVK mutations on protein prenylation, autophagy and programmed cell death in SH-SY5Y neuroblastoma cell lines. SH-SY5Y cells were transiently transfected, with the pCMV-6 plasmid containing MVK wild type and the two mutated sequences. Protein prenylation levels were evaluated using GFP-RhoA-F to assess farnesylation, and GFP-RhoA to evaluate geranylgeranylation; autophagy was measured by evaluating LC3 and p62 protein levels, while Annexin V-FITC and Propidium Iodide staining allowed apoptosis detection. MVK mutants' over-expression causes decreased levels of farnesylation and geranylgeranylation, and also increased LC3 lipidation in SH-SY5Y, with concomitant p62 accumulation. Treatment with bafilomycin A1 (an inhibitor of vacuolar H+-ATPase, a late autophagy inhibitor) further increase LC3-II and p62 levels, suggesting that degradation of autophagolysosome could be impaired. SH-SY5Y, with both MVK mutants, showed apoptosis increase; the presence of N301T associated with augmented cell death. We hypothesize that mevalonate pathway impairment causes alteration of farnesylation and geranylgeranylation proteins and alteration of the autophagic flux; these changes can induce apoptosis, possibly more relevant in the presence of N301T mutation. © 2017 The Author(s)Published by S. Karger AG, Basel.

  18. Differential metallothionein expression in oral lichen planus and amalgam-associated oral lichenoid lesions.

    Science.gov (United States)

    Mendes, G-G; Servato, J-P-S; Borges, F-C; Rosa, R-R; Siqueira, C-S; de Faria, P-R; Loyola, A-M; Cardoso, S-V

    2018-05-01

    Oral lichen planus (OLP) is a chronic inflammatory disease mediated by T cells, which manifests as reticular (white) or erosive (red) lesions, that are eventually painful. Oral lichenoid lesion (OLL) are distinguished from OLP by the presence of precipitating factors. The aim of this study was to evaluate whether the presence of metallothionein, which is involved in anti-apoptotic pathways and the anti-oxidative response, could serve as a differential diagnostic for OLP and OLL. We evaluated the expression of metallothionein in 40 cases of OLP and 20 cases of OLL using immunohistochemistry. White OLP has higher concentrations of metallothionein than red OLP in basal and parabasal layers. Moreover, metallothionein was more frequently observed in the cytoplasm and nuclei of basal cells in OLP patients compared to the same regions of OLL cases. Metallothionein levels are related to OLP severity and may contribute to a differential diagnosis between OLP and OLL.

  19. Metallothionein expression during liver regeneration after partial hepatectomy in cadmium-pretreated rats

    Energy Technology Data Exchange (ETDEWEB)

    Margeli, A.P. (Dept. of Forensic Medicine and Toxicology, School of Medicine, Univ. of Athens (Greece)); Theocharis, S.E. (Dept. of Forensic Medicine and Toxicology, School of Medicine, Univ. of Athens (Greece)); Yannacou, N.N. (Dept. of Forensic Medicine and Toxicology, School of Medicine, Univ. of Athens (Greece)); Spiliopoulou, C. (Dept. of Forensic Medicine and Toxicology, School of Medicine, Univ. of Athens (Greece)); Koutselinis, A. (Dept. of Forensic Medicine and Toxicology, School of Medicine, Univ. of Athens (Greece))

    1994-10-01

    Metallothionein is a low molecular mass protein inducible mainly by heavy metals, having high affinity for binding cadmium, zinc and copper. In the present study we investigated the expression of metallothionein in regenerating liver, at different time intervals, in cadmium pretreated partially hepatectomized rats. Liver metallothionein is highly expressed during regeneration induced by partial hepatectomy in rats, providing zinc within the rapidly growing tissue. Cadmium pretreatment caused inhibition of the first peak of liver regeneration, while metallothionein expression was markedly more prominent in the liver residues of cadmium-pretreated rats. These results demonstrate that although metallothionein able to bind temporarily metal ions as zinc and cadmium has been highly expressed, the liver regenerative process was inhibited possibly due to the effects of cadmium on other pivotal events necessary to the DNA replication. (orig.)

  20. Cadmium induces a novel metallothionein and phytochelatin 2 in an aquatic fungus

    International Nuclear Information System (INIS)

    Jaeckel, Petra; Krauss, Gudrun; Menge, Sieglinde; Schierhorn, Angelika; Ruecknagel, Peter; Krauss, Gerd-Joachim

    2005-01-01

    Cadmium stress response was measured at the thiol peptide level in an aquatic hyphomycete (Heliscus lugdunensis). In liquid culture, 0.1mM cadmium increased the glutathione (GSH) content and induced the synthesis of additional thiol peptides. HPLC, electrospray ionization mass spectrometry, and Edman degradation confirmed that a novel small metallothionein as well as phytochelatin (PC2) were synthesized. The metallothionein has a high homology to family 8 metallothioneins (http://www.expasy.ch/cgi-bin/lists?metallo.txt). The bonding of at least two cadmium ions to the metallothionein was demonstrated by mass spectrometry (MALDI MS). This is the first time that simultaneous induction of metallothionein and phytochelatin accompanied by an increase in GSH level has been shown in a fungus under cadmium stress, indicating a potential function of these complexing agents for in vivo heavy metal detoxification. The method presented here should be applicable as biomarker tool. ol

  1. Thermodynamics of Pb(ii) and Zn(ii) binding to MT-3, a neurologically important metallothionein.

    Science.gov (United States)

    Carpenter, M C; Shami Shah, A; DeSilva, S; Gleaton, A; Su, A; Goundie, B; Croteau, M L; Stevenson, M J; Wilcox, D E; Austin, R N

    2016-06-01

    Isothermal titration calorimetry (ITC) was used to quantify the thermodynamics of Pb(2+) and Zn(2+) binding to metallothionein-3 (MT-3). Pb(2+) binds to zinc-replete Zn7MT-3 displacing each zinc ion with a similar change in free energy (ΔG) and enthalpy (ΔH). EDTA chelation measurements of Zn7MT-3 and Pb7MT-3 reveal that both metal ions are extracted in a tri-phasic process, indicating that they bind to the protein in three populations with different binding thermodynamics. Metal binding is entropically favoured, with an enthalpic penalty that reflects the enthalpic cost of cysteine deprotonation accompanying thiolate ligation of the metal ions. These data indicate that Pb(2+) binding to both apo MT-3 and Zn7MT-3 is thermodynamically favourable, and implicate MT-3 in neuronal lead biochemistry.

  2. Shaping mechanisms of metal specificity in a family of metazoan metallothioneins: evolutionary differentiation of mollusc metallothioneins

    Directory of Open Access Journals (Sweden)

    Atrian Sílvia

    2011-01-01

    Full Text Available Abstract Background The degree of metal binding specificity in metalloproteins such as metallothioneins (MTs can be crucial for their functional accuracy. Unlike most other animal species, pulmonate molluscs possess homometallic MT isoforms loaded with Cu+ or Cd2+. They have, so far, been obtained as native metal-MT complexes from snail tissues, where they are involved in the metabolism of the metal ion species bound to the respective isoform. However, it has not as yet been discerned if their specific metal occupation is the result of a rigid control of metal availability, or isoform expression programming in the hosting tissues or of structural differences of the respective peptides determining the coordinative options for the different metal ions. In this study, the Roman snail (Helix pomatia Cu-loaded and Cd-loaded isoforms (HpCuMT and HpCdMT were used as model molecules in order to elucidate the biochemical and evolutionary mechanisms permitting pulmonate MTs to achieve specificity for their cognate metal ion. Results HpCuMT and HpCdMT were recombinantly synthesized in the presence of Cd2+, Zn2+ or Cu2+ and corresponding metal complexes analysed by electrospray mass spectrometry and circular dichroism (CD and ultra violet-visible (UV-Vis spectrophotometry. Both MT isoforms were only able to form unique, homometallic and stable complexes (Cd6-HpCdMT and Cu12-HpCuMT with their cognate metal ions. Yeast complementation assays demonstrated that the two isoforms assumed metal-specific functions, in agreement with their binding preferences, in heterologous eukaryotic environments. In the snail organism, the functional metal specificity of HpCdMT and HpCuMT was contributed by metal-specific transcription programming and cell-specific expression. Sequence elucidation and phylogenetic analysis of MT isoforms from a number of snail species revealed that they possess an unspecific and two metal-specific MT isoforms, whose metal specificity was

  3. Overexpression of miR-185 inhibits autophagy and apoptosis of dopaminergic neurons by regulating the AMPK/mTOR signaling pathway in Parkinson's disease

    OpenAIRE

    Wen, Zhi; Zhang, Jie; Tang, Peng; Tu, Ning; Wang, Ke; Wu, Guangyao

    2017-01-01

    Parkinson's disease (PD) is an age-associated neurodegenerative disorder characterized by the death of dopaminergic neurons in the substantia nigra pars compacta. Activation of 5′-adenosine monophosphate-activated protein kinase (AMPK) has been suggested to be associated with PD pathogenesis. The aim of the present study was to investigate the effects of the aberrant expression of microRNA-185 (miR-185) in PD. A 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced in vitro model of PD ...

  4. Effects of buthionine sulfoximine nifurtimox and benznidazole upon trypanothione and metallothionein proteins in Trypanosoma cruzi.

    Directory of Open Access Journals (Sweden)

    JUAN DIEGO MAYA

    2004-01-01

    Full Text Available Proteins rich in sulfhydryl groups, such as metallothionein, are present in several strains of the parasite Trypanosoma cruzi, the etiological agent of Chagas' disease. Metallothionein-like protein concentrations ranged from 5.1 to 13.2 pmol/mg protein depending on the parasite strain and growth phase. Nifurtimox and benznidazole, used in the treatment of Chagas' disease, decreased metallothionein activity by approximately 70%. T. cruzi metallothionein was induced by ZnCl2. Metallothionein from T. cruzi was partially purified and its monobromobimane derivative showed a molecular weight of approximately 10,000 Da by SDS-PAGE analysis. The concentration of trypanothione, the major glutathione conjugate in T. cruzi, ranged from 3.8 to 10.8 nmol/mg protein, depending on the culture phase. The addition of buthionine sulfoximine to the protozoal culture considerably reduced the concentration of trypanothione and had no effect upon the metallothionein concentration. The possible contribution of metallothionein-like proteins to drug resistance in T. cruzi is discussed.

  5. Increased levels of metallothionein in placenta of smokers

    International Nuclear Information System (INIS)

    Ronco, Ana Maria; Arguello, Graciela; Suazo, Myriam; Llanos, Miguel N.

    2005-01-01

    Experiments were designed to evaluate and compare metallothionein (MT), zinc and cadmium levels in human placentas of smoking and non-smoking women. Smoking was assessed by self-reported cigarette consumption and urine cotinine levels before delivery. Smoking pregnant women with urine cotinine levels higher than 130 ng/ml were included in the smoking group. Determination of placental MT was performed by western blot analysis after tissue homogenization and saturation with cadmium chloride (1000 ppm). Metallothionein was analyzed with a monoclonal antibody raised against MT-1 and MT-2 and with a second anti mouse antibody conjugated to alkaline phosphatase. Zinc and cadmium were determined by neutron activation analysis and atomic absorption spectrometry respectively. Smokers showed higher placental MT and cadmium levels, together with decreased newborn birth weights, as compared to non-smokers. The semi-quantitative analysis of western blots by band densitometry indicated that darker bands corresponded to MT present in smokers' samples. This study confirms that cigarette smoking increases cadmium accumulation in placental tissue and suggests that this element has a stimulatory effect on placental MT production

  6. Noncooperative cadmium(II) binding to human metallothionein 1a

    International Nuclear Information System (INIS)

    Sutherland, Duncan E.K.; Stillman, Martin J.

    2008-01-01

    The two-domain (βα) mammalian metallothionein binds seven divalent metals, however, the binding mechanism is not well characterized and recent reports require the presence of the partially metallated protein. In this paper, step-wise metallation of the metal-free, two-domain βα-rhMT and the isolated β-rhMT using Cd(II) is shown to proceed in a noncooperative manner by analysis of electrospray ionization mass spectrometric data. Under limiting amounts of Cd(II), all intermediate metallation states up to the fully metallated Cd 3 -β-rhMT and Cd 7 -βα-rhMT were observed. Addition of excess Cd(II), resulted in formation of the supermetallated (metallation in excess of normal levels) Cd 4 -β- and Cd 8 -βα-metallothionein species. These data establish that noncooperative cadmium metallation is a property of each isolated domain and the complete two-domain protein. Our data now also establish that supermetallation is a property that may provide information about the mechanism of metal transfer to other proteins

  7. Metallothionein metabolism in the streptozotocin-diabetic rat

    International Nuclear Information System (INIS)

    Chen, M.L.; Failla, M.L.

    1986-01-01

    Earlier reports from their laboratory showed the induction of the insulin-deficient diabetic state in adult rats was associated with an accumulation of zinc, copper, and a metallothionein-like zinc and copper binding protein in the soluble fraction of liver and kidney. Based upon chromatographic and electrophoretic properties, -SH to metal ratio and amino acid composition, they now report that elevated concentrations of metallothioneins (MT)-I and -II are indeed present in diabetic rat liver and kidney cytosol. The relative rates of MT synthesis in tissues from diabetic and control rats were measured by comparing incorporation of 35 S-cysteine into MT vs. total cytoplasmic proteins at 5 h after injection of the precursor. The relative rates of MT synthesis in livers from rats diabetic for 10 d and fed either chow or purified diet containing 13 or 35 ppm copper were 1.4, 2.3 and 2.8 times greater, respectively, than control rats fed the same diets. Higher relative rates of MT synthesis were also observed in kidneys from diabetic rats fed purified diets compared to controls. Maximal relative rates of MT synthesis in diabetic liver and kidney were observed at 4 and 10 d, respectively, after onset of diabetes. The half-lives of cytoplasmic MT in liver and kidney from diabetic (10 d) rats were 1.3 and 2.6 days, respectively; half-lives of MT in control liver and kidney were 5.0 and 2.1 days, respectively

  8. Protective/detoxicative function of metallothionein in the rat brain and blood induced by controlled cadmium doses

    Directory of Open Access Journals (Sweden)

    H. N. Shiyntum

    2015-09-01

    Full Text Available Cadmiumclassified as a major carcinogen is considered a poisonous and unwanted heavy metal to a lot of tissues in many organisms. Of many publications already available, the general consensus is that the cadmium attenuating element is metallothionein (MT through its interchangeable mechanism with Zn triggered by the presence of Cd, providing binding sites for Cd ions. MT was first discovered in the kidney cortex of the horse; it represents a low molecular weight protein, rich in cysteine residues which effectively bind with metals. Its functions consist in detoxification of heavy metals like mercury, arsenic, cadmium, homeostasis of essential metals including copper and zinc, anti-oxidation against reactive oxygen species, protection against DNA damage, oxidative stress, cell survival, angiogenesis, apoptosis, and increase of proliferation. In this work, we sought to highlight the protective function of MT in the brain and serum of rats by means of detoxification under induced effects of controlled Cd doses. We have done this by exposing Wistar rats to Cd at different doses in drinking water at different time intervals. In two independent experiments, 58 rats were subjected to 0.1 or 1.0 µg Cd2+/kg of body weight for 15 or 36 days under different conditions. The obtained data indicates the different functioning systems for the brain and the blood for MT metabolism under Cd effect. Our results indicate significant loss of metallothionein level in the brain and important increases in the amount of MT in serum proving that even minimal ingestion of toxic Cd is enough to trigger the release of MT protein in blood.

  9. Induced synthesis of metallothionein by pig kidney cells in vitro in response to cadmium

    Energy Technology Data Exchange (ETDEWEB)

    Webb, M; Daniel, M

    1975-01-01

    Cells of a line (K7), derived from the cortex of the adult pig kidney, synthesize and accumulate high levels of metallothionein when grown in vitro in the presence of low concentrations (0.5 ..mu..g/ml) of Cd/sup 2 +/. This indicates that the accumulation of this protein in the kidneys of animals exposed to cadmium is due at least partly to synthesis in situ, and not solely to uptake by the renal cells of metallothionein produced by the liver. It is suggested that the ability to synthesize large amounts of metallothionein indicates the tubular origin of the cells of this line.

  10. Selective cerebral perfusion prevents abnormalities in glutamate cycling and neuronal apoptosis in a model of infant deep hypothermic circulatory arrest and reperfusion.

    Science.gov (United States)

    Kajimoto, Masaki; Ledee, Dolena R; Olson, Aaron K; Isern, Nancy G; Robillard-Frayne, Isabelle; Des Rosiers, Christine; Portman, Michael A

    2016-11-01

    Deep hypothermic circulatory arrest is often required for the repair of complex congenital cardiac defects in infants. However, deep hypothermic circulatory arrest induces neuroapoptosis associated with later development of neurocognitive abnormalities. Selective cerebral perfusion theoretically provides superior neural protection possibly through modifications in cerebral substrate oxidation and closely integrated glutamate cycling. We tested the hypothesis that selective cerebral perfusion modulates glucose utilization, and ameliorates abnormalities in glutamate flux, which occur in association with neuroapoptosis during deep hypothermic circulatory arrest. Eighteen infant male Yorkshire piglets were assigned randomly to two groups of seven (deep hypothermic circulatory arrest or deep hypothermic circulatory arrest with selective cerebral perfusion for 60 minutes at 18℃) and four control pigs without cardiopulmonary bypass support. Carbon-13-labeled glucose as a metabolic tracer was infused, and gas chromatography-mass spectrometry and nuclear magnetic resonance were used for metabolic analysis in the frontal cortex. Following 2.5 h of cerebral reperfusion, we observed similar cerebral adenosine triphosphate levels, absolute levels of lactate and citric acid cycle intermediates, and carbon-13 enrichment among three groups. However, deep hypothermic circulatory arrest induced significant abnormalities in glutamate cycling resulting in reduced glutamate/glutamine and elevated γ-aminobutyric acid/glutamate along with neuroapoptosis, which were all prevented by selective cerebral perfusion. The data suggest that selective cerebral perfusion prevents these modifications in glutamate/glutamine/γ-aminobutyric acid cycling and protects the cerebral cortex from apoptosis. © The Author(s) 2016.

  11. Determination of metallothioneins based on the enhanced peroxidase-like activity of mercury-coated gold nanoparticles aggregated by metallothioneins

    International Nuclear Information System (INIS)

    Li, Xue-Jiao; Wang, Yong-Sheng; Yang, Sheng-Yuan; Tang, Xian; Zhou, Bin; Wang, Xiao-Feng; Zhu, Yu-Feng; Huang, Yan-Qin; He, Shun-Zhen; Liu, Lu

    2016-01-01

    We report on a photometric method for the determination of the metallothioneins (MTs). It is known that citrate capped gold nanoparticles (AuNPs) coated with traces of mercury possess peroxidase-like properties that can catalyze the oxidation of 2,2′-azino-bis(3-ethylbenzothiazoline- 6-sulfonate) (ABTS) to form a blue product in acetate buffer of pH 4.5. It is found that if the AuNPs are first aggregated by the cysteine-rich metallothioneins, the peroxidase-like properties of the resulting aggregates (AuNP-Hg-MTs) cause a largely accelerated oxidation of ABTS. The effect of adding MTs to such a solution is used to quantify the MTs by a kinetic assay. Changes in absorbance at 416 nm are linearly correlated to the concentration of MTs in the 4.3 to 49 nM range, and the detection limit is 1.3 nM. The method was successfully applied to the determination of MTs in (spiked) human urine. The strategy may pave the way for related detection platforms. (author)

  12. P2X7 Cell Death Receptor Activation and Mitochondrial Impairment in Oxaliplatin-Induced Apoptosis and Neuronal Injury: Cellular Mechanisms and In Vivo Approach.

    Directory of Open Access Journals (Sweden)

    France Massicot

    Full Text Available Limited information is available regarding the cellular mechanisms of oxaliplatin-induced painful neuropathy during exposure of patients to this drug. We therefore determined oxidative stress in cultured cells and evaluated its occurrence in C57BL/6 mice. Using both cultured neuroblastoma (SH-SY5Y and macrophage (RAW 264.7 cell lines and also brain tissues of oxaliplatin-treated mice, we investigated whether oxaliplatin (OXA induces oxidative stress and apoptosis. Cultured cells were treated with 2-200 µM OXA for 24 h. The effects of pharmacological inhibitors of oxidative stress or inflammation (N-acetyl cysteine, ibuprofen, acetaminophen were also tested. Inhibitors were added 30 min before OXA treatment and then in combination with OXA for 24 h. In SH-SY5Y cells, OXA caused a significant dose-dependent decrease in viability, a large increase in ROS and NO production, lipid peroxidation and mitochondrial impairment as assessed by a drop in mitochondrial membrane potential, which are deleterious for the cell. An increase in levels of negatively charged phospholipids such as cardiolipin but also phosphatidylserine and phosphatidylinositol, was also observed. Additionally, OXA caused concentration-dependent P2X7 receptor activation, increased chromatin condensation and caspase-3 activation associated with TNF-α and IL-6 release. The majority of these toxic effects were equally observed in Raw 264.7 which also presented high levels of PGE2. Pretreatment of SH-SY5Y cells with pharmacological inhibitors significantly reduced or blocked all the neurotoxic OXA effects. In OXA-treated mice (28 mg/kg cumulated dose significant cold hyperalgesia and oxidative stress in the tested brain areas were shown. Our study suggests that targeting P2X7 receptor activation and mitochondrial impairment might be a potential therapeutic strategy against OXA-induced neuropathic pain.

  13. LncRNA TUG1 sponges microRNA-9 to promote neurons apoptosis by up-regulated Bcl2l11 under ischemia.

    Science.gov (United States)

    Chen, Shengcai; Wang, Mengdie; Yang, Hang; Mao, Ling; He, Quanwei; Jin, Huijuan; Ye, Zi-Ming; Luo, Xue-Ying; Xia, Yuan-Peng; Hu, Bo

    2017-03-25

    Emerging studies have illustrated that LncRNAs TUG1 play critical roles in multiple biologic processes. However, the LncRNA TUG1 expression and function in ischemic stroke have not been reported yet. In this study, we found that LncRNA TUG1 expression was significantly up-regulated in brain ischemic penumbra from rat middle carotid artery occlusion (MCAO) model, while similar results were also observed in cultured neurons under oxygen-glucose deprivation (OGD) insult. Knockdown of TUG1 decreased the ratio of apoptotic cells and promoted cells survival in vitro, which may be regulated by the elevated miRNA-9 expression and decreased Bcl2l11 protein. Furthermore, TUG1 could directly interact with miR-9 and down-regulating miR-9 could efficiently reverse the function of TUG1 on the Bcl2l11 expression. In summary, our result sheds light on the role of LncRNA TUG1 as a miRNA sponge for ischemic stroke, possibly providing a new therapeutic target in stroke. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Metallothionein-I and -III expression in animal models of Alzheimer disease

    DEFF Research Database (Denmark)

    Carrasco, J; Adlard, P; Cotman, C

    2006-01-01

    Previous studies have described altered expression of metallothioneins (MTs) in neurodegenerative diseases like multiple sclerosis (MS), Down syndrome, and Alzheimer's disease (AD). In order to gain insight into the possible role of MTs in neurodegenerative processes and especially in human...

  15. Temporal variations in metallothionein concentration and subcellular distribution of metals in gills and digestive glands of the oyster Crassostrea angulata

    Directory of Open Access Journals (Sweden)

    Chiara Trombini

    2010-11-01

    Full Text Available The metallothionein levels and metal concentrations in whole body, digestive gland and gills of Crassostrea angulata were analyzed in field samples collected from the River Guadalquivir estuary over several years following a mining waste spill upstream. The subcellular distribution of metals was analyzed to determine the mechanisms involved in the detoxification process. The highest metallothionein levels were reported in the digestive gland shortly after the mining contamination event. In this organ, metals are stored preferentially in the non-cytosolic fraction when increased bioaccumulation takes place. In the cytosol of the gills, metals are associated with metallothionein, whereas in the digestive gland, the distribution of metals between metallothioneins and high molecular weight proteins is similar. Metallothionein variation cannot be explained by metals alone; other abiotic factors must be taken into account. In order to use metallothionein as a metal exposure biomarker in field studies, natural variability needs to be taken into account for the correct interpretation of results.

  16. Role of metallothioneins in peripheral nerve function and regeneration

    DEFF Research Database (Denmark)

    Ceballos, D; Lago, N; Verdú, E

    2003-01-01

    The physiological role of the metallothionein (MT) family of proteins during peripheral nerve injury and regeneration was examined in Mt1+ 2 and Mt3 knockout (KO) mice. To this end, the right sciatic nerve was crushed, and the regeneration distance was evaluated by the pinch test 2-7 days....... The improved regeneration observed with the Mt3 KO mice was confirmed by compound nerve action potentials that were recorded from digital nerves at 14 dpl only in this group. We conclude that Mt3 normally inhibits peripheral nerve regeneration........ Moreover, the number of regenerating axons in the distal tibial nerve was significantly higher in Mt3KO mice than in the other two strains at 14 dpl. Immunoreactive profiles to protein gene product 9.5 were present in the epidermis and the sweat glands of the plantar skin of the hindpaw of the Mt3 KO group...

  17. The involvement of metallothionein in the development of aquatic invertebrate

    International Nuclear Information System (INIS)

    Mao Huan; Wang Dahui; Yang Wanxi

    2012-01-01

    The many documents on metallothioneins (MTs) in aquatic organisms focus especially on their use as biomarkers in environmental monitoring programs, but there are a few papers that summarize the physiological role of MTs in aquatic organisms especially in their development. The multifaceted role of MTs include involvement in homeostasis, protection against heavy metals and oxidant damage, metabolic regulation, sequestration and/or redox control. MTs could be induced by heavy metals which are able to hinder gametogenesis, suppress embryogenesis, and hamper development. Here we pay more attention on the non-essential metal cadmium, which is the most studied heavy metal regarding MTs, and its effects on the development of aquatic invertebrates. In this paper, we have collected published information on MTs in aquatic organisms – mollusks, crustaceans, etc., and summarize its functions in aquatic invertebrates, especially those related to their development.

  18. Repair of DNA damage in the human metallothionein gene family

    International Nuclear Information System (INIS)

    Leadon, S.A.; Snowden, M.M.

    1987-01-01

    In order to distinguish enhanced repair of a sequence due to its transcriptional activity from enhanced repair due to chromatin alterations brought about by integration of a sequence into the genome, we have investigated the repair of damage both in endogenous genes and in cell lines that contain an integrated gene with an inducible promoter. The endogenous genes we are studying are the metallothioneins (MTs), a multigene family in man consisting of about 10-12 members. Cultured cells were exposed to 10-J/m 2 uv light and allowed to repair in the presence of bromodeoxyuridine. The DNA was then isolated, digested with Eco RI, and fully hybrid density DNA made by semiconservative synthesis was separated from unreplicated DNA by centrifugation in CsCl density gradients. Unreplicated, parental-density DNA was then reacted with a monoclonal antibody against bromouracil. 1 ref., 1 fig., 1 tab

  19. Metallothionein expression in chloroplasts enhances mercury accumulation and phytoremediation capability.

    Science.gov (United States)

    Ruiz, Oscar N; Alvarez, Derry; Torres, Cesar; Roman, Laura; Daniell, Henry

    2011-06-01

    Genetic engineering to enhance mercury phytoremediation has been accomplished by expression of the merAB genes that protects the cell by converting Hg[II] into Hg[0] which volatilizes from the cell. A drawback of this approach is that toxic Hg is released back into the environment. A better phytoremediation strategy would be to accumulate mercury inside plants for subsequent retrieval. We report here the development of a transplastomic approach to express the mouse metallothionein gene (mt1) and accumulate mercury in high concentrations within plant cells. Real-time PCR analysis showed that up to 1284 copies of the mt1 gene were found per cell when compared with 1326 copies of the 16S rrn gene, thereby attaining homoplasmy. Past studies in chloroplast transformation used qualitative Southern blots to evaluate indirectly transgene copy number, whereas we used real-time PCR for the first time to establish homoplasmy and estimate transgene copy number and transcript levels. The mt1 transcript levels were very high with 183,000 copies per ng of RNA or 41% the abundance of the 16S rrn transcripts. The transplastomic lines were resistant up to 20 μm mercury and maintained high chlorophyll content and biomass. Although the transgenic plants accumulated high concentrations of mercury in all tissues, leaves accumulated up to 106 ng, indicating active phytoremediation and translocation of mercury. Such accumulation of mercury in plant tissues facilitates proper disposal or recycling. This study reports, for the first time, the use of metallothioneins in plants for mercury phytoremediation. Chloroplast genetic engineering approach is useful to express metal-scavenging proteins for phytoremediation. © 2011 The Authors. Plant Biotechnology Journal © 2011 Society for Experimental Biology, Association of Applied Biologists and Blackwell Publishing Ltd.

  20. Role of ARF6 in internalization of metal-binding proteins, metallothionein and transferrin, and cadmium-metallothionein toxicity in kidney proximal tubule cells

    International Nuclear Information System (INIS)

    Wolff, Natascha A.; Lee, Wing-Kee; Abouhamed, Marouan; Thevenod, Frank

    2008-01-01

    Filtered metal-protein complexes, such as cadmium-metallothionein-1 (CdMT-1) or transferrin (Tf) are apically endocytosed partly via megalin/cubilin by kidney proximal tubule (PT) cells where CdMT-1 internalization causes apoptosis. Small GTPase ARF (ADP-ribosylation factor) proteins regulate endocytosis and vesicular trafficking. We investigated roles of ARF6, which has been shown to be involved in internalization of ligands and endocytic trafficking in PT cells, following MT-1/CdMT-1 and Tf uptake by PT cells. WKPT-0293 Cl.2 cells derived from rat PT S1 segment were transfected with hemagglutinin-tagged wild-type (ARF6-WT) or dominant negative (ARF6-T27N) forms of ARF6. Using immunofluorescence, endogenous ARF6 was associated with the plasma membrane (PM) as well as juxtanuclear and co-localized with Rab5a and Rab11 involved in early and recycling endosomal trafficking. Immunofluorescence staining of megalin showed reduced surface labelling in ARF6 dominant negative (ARF6-DN) cells. Intracellular Alexa Fluor 546-conjugated MT-1 uptake was reduced in ARF6-DN cells and CdMT-1 (14.8 μM for 24 h) toxicity was significantly attenuated from 27.3 ± 3.9% in ARF6-WT to 11.1 ± 4.0% in ARF6-DN cells (n = 6, P < 0.02). Moreover, reduced Alexa Fluor 546-conjugated Tf uptake was observed in ARF-DN cells (75.0 ± 4.6% versus 3.9 ± 3.9% of ARF6-WT cells, n = 3, P < 0.01) and/or remained near the PM (89.3 ± 5. 6% versus 45.2 ± 14.3% of ARF6-WT cells, n = 3, P < 0.05). In conclusion, the data support roles for ARF6 in receptor-mediated endocytosis and trafficking of MT-1/Tf to endosomes/lysosomes and CdMT-1 toxicity of PT cells

  1. Short-term exposure of mice to gasoline vapor increases the metallothionein expression in the brain, lungs and kidney.

    Science.gov (United States)

    Grebić, D; Jakovac, H; Mrakovcić-Sutić, I; Tomac, J; Bulog, A; Micović, V; Radosević-Stasić, B

    2007-06-01

    Environmental airborne pollution has been repeatedly shown to affect multiple aspects of brain and cardiopulmonary function, leading to cognitive and behavioral changes and to the pronounced inflammatory response in the respiratory airways. Since in the cellular defense system the important role might have stress proteins-metallothionein (MT)-I and MT-II, which are involved in sequestration and dispersal of metal ions, regulation of the biosynthesis and activities of zinc-dependent transcription factors, as well as in cellular protection from reactive oxygen species, genotoxicity and apoptosis, in this study we investigated their expression in the brain, lungs and kidney, following intermittent exposure of mice to gasoline vapor. Control groups consisted of intact mice and of those closed in the metabolic chamber and ventilated with fresh air. The data obtained by immunohistochemistry showed that gasoline inhalation markedly upregulated the MTs expression in tissues which were directly or indirectly exposed to toxic components, significantly increasing the number of MT I+II positive cells in CNS (the entorhinal cortex, ependymal cells, astroglial cells in subventricular zone and inside the brain parenchyma, subgranular and CA1-CA3 zone of the dentate gyrus in hippocampus and macrophages-like cells in perivascular spaces), in the lungs (pneumocytes type I and type II) and in the kidneys (parietal wall of Bowman capsule, proximal and distal tubules). The data point to the protective and growth-regulatory effects of MT I + II on places of injuries, induced by inhalation of gasoline vapor.

  2. METALLOTHIONEINS AS SENSORS AND CONTROLS EXCHANGE OF METALS IN THE CELLS

    Directory of Open Access Journals (Sweden)

    V. A. Kutyakov

    2014-01-01

    Full Text Available The basic information on the classification, structure, induction and degradation, functions of the protein family – metallothionein (MT, including CNS in health and disease are presented in this review. It was found that four major isoforms of metallothionein perform different biological roles, are localized in dif- ferent tissues. Induction of MT is a universal reaction to the impact of a variety of stress factors. In recent years, understanding of the role of metallothioneins in metal homeostasis in the tissues in normal and pathological conditions have changed significantly. Notes polyfunctionality metallothioneins (transport of metal ions, maintaining redox reactions, tread, signal, modulated and regulatory functions and their im- pact on basic cellular functions such as proliferation, differentiation, programmed cell death. Further- more, a special role is shown MT in the pathogenesis of cardiovascular, neurodegenerative and neoplastic disorders.Currently, these molecules are increasingly considered as potential targets for therapy of a wide range of diseases and the development of targeted approaches to the regulation of expression of MT – one of the promising areas of pharmacology and toxicology. Stressed the safety of metallothioneins as therapeutic agents.

  3. Shapes of Differential Pulse Voltammograms and Level of Metallothionein at Different Animal Species

    Directory of Open Access Journals (Sweden)

    Rene Kizek

    2007-10-01

    Full Text Available Metallothioneins play a key role in maintaining homeostasis of essential metalsand in protecting of cells against metal toxicity as well as oxidative damaging. Exceptinghumans, blood levels of metallothionein have not yet been reported from any animalspecies. Blood plasma samples of 9 animal species were analysed by the adsorptive transferstripping technique to obtain species specific voltammograms. Quite distinct records wereobtained from the Takin (Budorcas taxicolor, while other interesting records were observedin samples from the European Bison (Bison bonasus bonasus and the Red-eared Slider(Trachemys scripta elegans. To quantify metallothionein the catalytic peak Cat2 was used,well developed in the Domestic Fowl (Gallus gallus f. domestica and showing a very lowsignal in the Red Deer (Cervus elaphus. The highest levels of metallothionein reachingover 20 μM were found in the Domestic Fowl. High levels of MT were also found in theBearded Dragon (Pogona vitticeps and the Grey Wolf (Canis lupus lupus. The lowestvalues of about 1-3 μM were determined in the Red-eared Slider, Takin and Red Deer. Employing a simple electrochemical detection it was possible to examine variation in blood metallothionein in different species of vertebrates.

  4. Anti-apoptotic signaling and failure of apoptosis in the ischemic rat hippocampus

    DEFF Research Database (Denmark)

    Müller, Georg Johannes; Lassmann, Hans; Johansen, Flemming Fryd

    2007-01-01

    Several anti-apoptotic proteins are induced in CA1 neurons after transient forebrain ischemia (TFI), but fail to protect the majority of these cells from demise. Correlating cell death morphologies (apoptosis-like and necrosis-like death) with immunohistochemistry (IHC), we investigated whether...... anti-apoptosis contributes to survival, compromises apoptosis effector functions and/or delays death in CA1 neurons 1-7 days after TFI. As surrogate markers for bioenergetic failure, the IHC of respiratory chain complex (RCC) subunits was investigated. Dentate granule cell (DGC) apoptosis following...... colchicine injection severed as a reference for classical apoptosis. Heat shock protein 70 (Hsp70), neuronal apoptosis inhibitory protein (NAIP) and manganese superoxide dismutase (MnSOD) were upregulated in the majority of intact CA1 neurons paralleling the occurrence of CA1 neuronal death (days 3...

  5. Some factors influencing liver metallothionein levels in rats and mice

    International Nuclear Information System (INIS)

    Jang, T.; Lee, M.

    1981-01-01

    Liver metallothionein (MT) was measured by the 203-mercury binding method of Piotrowski in the livers of rats and mice subjected to bilateral adrenalectomy or to sham adrenalectomy. Sham operation was followed by an increase in the level of MT at 24 hours; this immediately began to decrease, reaching control levels by 7 days. Adrenalectomy was also followed by an increase in MT, but the levels remained elevated for several days before beginning to decline. Mice which were adrenalectomized and allowed to recover for 28 days showed an increase in MT when subjected to sham operation. Ether anaesthesia without an incision did not increase the level of MT. Hypophysectomized mice had higher levels of MT than did controls, and these levels were further increased by sham adrenalectomy. Sprague-Dawley rats showed a similar response to adrenalectomy and to sham operation. It is concluded that the sham operation-induced increase in MT is probably not a result of a stress-induced release of adrenal hormones, but that adrenal hormones may play some role in the degradation or turnover of MT. The pituitary may also have some role in MT turnover

  6. The Functions of Metamorphic Metallothioneins in Zinc and Copper Metabolism.

    Science.gov (United States)

    Krężel, Artur; Maret, Wolfgang

    2017-06-09

    Recent discoveries in zinc biology provide a new platform for discussing the primary physiological functions of mammalian metallothioneins (MTs) and their exquisite zinc-dependent regulation. It is now understood that the control of cellular zinc homeostasis includes buffering of Zn 2+ ions at picomolar concentrations, extensive subcellular re-distribution of Zn 2+ , the loading of exocytotic vesicles with zinc species, and the control of Zn 2+ ion signalling. In parallel, characteristic features of human MTs became known: their graded affinities for Zn 2+ and the redox activity of their thiolate coordination environments. Unlike the single species that structural models of mammalian MTs describe with a set of seven divalent or eight to twelve monovalent metal ions, MTs are metamorphic. In vivo, they exist as many species differing in redox state and load with different metal ions. The functions of mammalian MTs should no longer be considered elusive or enigmatic because it is now evident that the reactivity and coordination dynamics of MTs with Zn 2+ and Cu⁺ match the biological requirements for controlling-binding and delivering-these cellular metal ions, thus completing a 60-year search for their functions. MT represents a unique biological principle for buffering the most competitive essential metal ions Zn 2+ and Cu⁺. How this knowledge translates to the function of other families of MTs awaits further insights into the specifics of how their properties relate to zinc and copper metabolism in other organisms.

  7. The Functions of Metamorphic Metallothioneins in Zinc and Copper Metabolism

    Directory of Open Access Journals (Sweden)

    Artur Krężel

    2017-06-01

    Full Text Available Recent discoveries in zinc biology provide a new platform for discussing the primary physiological functions of mammalian metallothioneins (MTs and their exquisite zinc-dependent regulation. It is now understood that the control of cellular zinc homeostasis includes buffering of Zn2+ ions at picomolar concentrations, extensive subcellular re-distribution of Zn2+, the loading of exocytotic vesicles with zinc species, and the control of Zn2+ ion signalling. In parallel, characteristic features of human MTs became known: their graded affinities for Zn2+ and the redox activity of their thiolate coordination environments. Unlike the single species that structural models of mammalian MTs describe with a set of seven divalent or eight to twelve monovalent metal ions, MTs are metamorphic. In vivo, they exist as many species differing in redox state and load with different metal ions. The functions of mammalian MTs should no longer be considered elusive or enigmatic because it is now evident that the reactivity and coordination dynamics of MTs with Zn2+ and Cu+ match the biological requirements for controlling—binding and delivering—these cellular metal ions, thus completing a 60-year search for their functions. MT represents a unique biological principle for buffering the most competitive essential metal ions Zn2+ and Cu+. How this knowledge translates to the function of other families of MTs awaits further insights into the specifics of how their properties relate to zinc and copper metabolism in other organisms.

  8. Mechanisms of Neuronal Apoptosis In Vivo

    Science.gov (United States)

    2004-02-01

    nitroproplonic acid, a compound from plants striatal tyrosine hydroxylase immunoperoxidase staining. Brain Res in the genus Astragalus. Arch Inst Cardiol...neurotransmitters stereotypic movements, and self-injurious behavior, in certain brain areas to environmental factors. There Furthermore, as adults, these...characterized by abnormal conduct such as repetitive may be related to similar abnormal behaviors of or stereotyped movements, poor skills in communica

  9. Metal and metallothionein content in tissues from wild and farmed Anguilla anguilla at commercial size.

    Science.gov (United States)

    Ureña, R; Peri, S; del Ramo, J; Torreblanca, A

    2007-05-01

    Metallothionein and metal content (Cd, Zn, Hg, Cu, Fe, Pb and Mn) were determined in various organs of commercially available eel (Anguilla anguilla) of similar size obtained from a local farm and from The Albufera Lake in Valencia (Spain). Farmed fish showed statistically significant higher Cd concentrations in liver and kidney whereas wild individuals had higher levels of Pb in blood and Zn in kidney. Significant positive correlations were found between metallothionein and Cd in kidney of farmed eel and between metallothionein and Cu in liver of wild ones. No statistically significant differences were found between the two populations in the concentration of any of the metals analyzed in muscle and in all instances these levels were lower than the limits established by the Spanish legislation for fish destined for human consumption.

  10. A synthetic cadmium metallothionein gene (PMCd1syn) of Paramecium species: expression, purification and characteristics of metallothionein protein.

    Science.gov (United States)

    Dar, Saira; Shuja, Rukhsana N; Shakoori, Abdul Rauf

    2013-02-01

    Metallothioneins (MTs) are metal binding proteins that are rich in cysteine residues constituting 10-30 % of the total protein, and in which the thiol groups bind to the metal ions. The increasing amount of metal ions in the medium have shown increased production of MTs by different organisms such as bacteria, protozoa and mammals like humans. PMCd1 is the first gene ever discovered in Paramecium, a ciliated protozoan, that could produce this MT in response to cadmium. In this study the PMCd1syn gene has been cloned in pET41a expression vector and expressed in an Escherichia coli BL21-codonplus strain for the first time. Since the gene PMCd1 amplified from Paramecium contained 10 codons, which could act as stop codons during expression in E. coli, this gene of 612 bps was synthesized to substitute these (stop) codons for the Paramecium sp. specific amino acids. For stability of the expressed protein, glutathione-S-transferase gene was fused with PMCd1syn gene and coexpressed. The cells expressing PMCd1syn demonstrated increased accumulation of cadmium. This is the first report of cadmium MT protein expressed from Paramecium species, particularly from synthetic MT gene (PMCd1syn). This fusion protein, the molecular weight of which has been confirmed to be 53.03 kDa with MALDI analysis, is rich in cysteine residues, and has been shown for the first time in this ciliate to bind to and sequester Cd(2+)-ions.

  11. Overexpressed human metallothionein IIA gene protects Chinese hamster ovary cells from killing by alkylating agents.

    OpenAIRE

    Kaina, B; Lohrer, H; Karin, M; Herrlich, P

    1990-01-01

    Experiments were designed to detect survival advantages that cells gain by overexpressing metallothionein (MT). Chinese hamster ovary K1-2 cells and an x-ray-sensitive derivative were transfected with a bovine papillomavirus (BPV)-linked construct carrying the human metallothionein IIA (hMT-IIA) gene. Transfectants survived 40-fold higher levels of cadmium chloride, harbored at least 30 copies of hMT-IIA, and contained 25- to 166-fold more MT than the parent cells. Even under conditions of re...

  12. Single and double metallothionein knockout in the nematode C. elegans reveals cadmium dependent and independent toxic effects on life history traits

    International Nuclear Information System (INIS)

    Hughes, Sam; Stuerzenbaum, Stephen R.

    2007-01-01

    The genome of the nematode Caenorhabditis elegans contains two metallothionein genes, both involved in metal homeostasis and/or detoxification. Single metallothionein knockout mutants have been created and now, for the first time, a double mutant has been isolated. Life history studies in the presence or absence of cadmium showed that all metallothionein mutants are viable. Although cadmium did not influence longevity, a dose dependent reduction in total brood size and volumetric growth was observed in wild type animals, which was magnified in single knockouts and further exacerbated in the double knockout. However, the metallothionein deletion caused two effects that are independent of cadmium exposure, namely all knockout strains displayed a reduced total brood size and the deletion of both metallothionein loci caused a significant reduction in volumetric growth. In summary, metallothionein is undoubtedly an important player in cadmium detoxification, but evidently also an important factor in cadmium independent pathways. - Metallothionein is a modifier of life-history parameters

  13. Single and double metallothionein knockout in the nematode C. elegans reveals cadmium dependent and independent toxic effects on life history traits

    Energy Technology Data Exchange (ETDEWEB)

    Hughes, Sam [School of Biosciences, Cardiff University, Main Building, Park Place, Cardiff CF10 3TL (United Kingdom); School of Biomedical and Health Sciences, Pharmaceutical Sciences Research Division, King' s College London, 150 Stamford Street, London SE1 9NH (United Kingdom); Stuerzenbaum, Stephen R. [School of Biosciences, Cardiff University, Main Building, Park Place, Cardiff CF10 3TL (United Kingdom) and School of Biomedical and Health Sciences, Pharmaceutical Sciences Research Division, King' s College London, 150 Stamford Street, London SE1 9NH (United Kingdom)]. E-mail: stephen.sturzenbaum@kcl.ac.uk

    2007-01-15

    The genome of the nematode Caenorhabditis elegans contains two metallothionein genes, both involved in metal homeostasis and/or detoxification. Single metallothionein knockout mutants have been created and now, for the first time, a double mutant has been isolated. Life history studies in the presence or absence of cadmium showed that all metallothionein mutants are viable. Although cadmium did not influence longevity, a dose dependent reduction in total brood size and volumetric growth was observed in wild type animals, which was magnified in single knockouts and further exacerbated in the double knockout. However, the metallothionein deletion caused two effects that are independent of cadmium exposure, namely all knockout strains displayed a reduced total brood size and the deletion of both metallothionein loci caused a significant reduction in volumetric growth. In summary, metallothionein is undoubtedly an important player in cadmium detoxification, but evidently also an important factor in cadmium independent pathways. - Metallothionein is a modifier of life-history parameters.

  14. Cadmium modulates adipocyte functions in metallothionein-null mice

    Energy Technology Data Exchange (ETDEWEB)

    Kawakami, Takashige; Nishiyama, Kaori; Kadota, Yoshito; Sato, Masao; Inoue, Masahisa; Suzuki, Shinya, E-mail: suzukis@ph.bunri-u.ac.jp

    2013-11-01

    Our previous study has demonstrated that exposure to cadmium (Cd), a toxic heavy metal, causes a reduction of adipocyte size and the modulation of adipokine expression. To further investigate the significance of the Cd action, we studied the effect of Cd on the white adipose tissue (WAT) of metallothionein null (MT{sup −/−}) mice, which cannot form atoxic Cd–MT complexes and are used for evaluating Cd as free ions, and wild type (MT{sup +/+}) mice. Cd administration more significantly reduced the adipocyte size of MT{sup −/−} mice than that of MT{sup +/+} mice. Cd exposure also induced macrophage recruitment to WAT with an increase in the expression level of Ccl2 (MCP-1) in the MT{sup −/−} mice. The in vitro exposure of Cd to adipocytes induce triglyceride release into culture medium, decrease in the expression levels of genes involved in fatty acid synthesis and lipid hydrolysis at 24 h, and at 48 h increase in phosphorylation of the lipid-droplet-associated protein perilipin, which facilitates the degradation of stored lipids in adipocytes. Therefore, the reduction in adipocyte size by Cd may arise from an imbalance between lipid synthesis and lipolysis. In addition, the expression levels of leptin, adiponectin and resistin decreased in adipocytes. Taken together, exposure to Cd may induce unusually small adipocytes and modulate the expression of adipokines differently from the case of physiologically small adipocytes, and may accelerate the risk of developing insulin resistance and type 2 diabetes. - Highlights: • Cd causes a marked reduction in adipocyte size in MT-null mice. • Cd enhances macrophage migration into adipose tissue and disrupt adipokine secretion. • MT gene alleviates Cd-induced adipocyte dysfunctions. • Cd enhances the degradation of stored lipids in adipocytes, mediated by perilipin. • Cd induces unusually small adipocytes and the abnormal expression of adipokines.

  15. Amount and metal composition of midgut gland metallothionein in shore crabs (Carcinus maenas) after exposure to cadmium in the food

    International Nuclear Information System (INIS)

    Pedersen, Knud Ladegaard; Bach, Louise Thornhøj; Bjerregaard, Poul

    2014-01-01

    Highlights: • Crabs were fed with Cd in concentrations of 1.1–5.1 μg g −1 food. • Metallothionein concentrations only increased at 5.1 μg g −1 . • Cd contents of metallothionein increased linearly with exposure. • A marked influence by the variable Cu contents on metal composition was recorded. • Digestive gland metallothionein is a poor biomarker for Cd exposure. - Abstract: Accumulation of cadmium in aquatic invertebrates may compromise human food safety and anthropogenic additions of cadmium to coastal areas cause concern. Induction of crustacean metallothionein has been suggested as a useful biomarker for contamination of the aquatic environment with cadmium. We investigated how exposure to low concentrations of cadmium in the food affects the subcellular binding of cadmium with the shore crab Carcinus maenas as model organism. Approximately 80% of the assimilated cadmium was bound in the soluble fraction of the midgut gland and of this, 82% was found in the metallothionein fraction. Metallothionein synthesis was only induced at the highest exposure level. However, the number of cadmium atoms bound per molecule of metallothionein increased linearly with exposure, from approximately 0.18 in the control group to 1.4 in a group administered food containing 5.1 μg Cd g −1 . We noted a marked interaction between the presence of copper and zinc in the midgut gland and the binding of cadmium. The usefulness of crustacean midgut gland metallothionein as a biomarker for cadmium exposure at modest levels was questioned since exposures at levels producing significant increases in the tissue contents of the metal did not result in elevated concentrations of metallothionein in the midgut gland

  16. Amount and metal composition of midgut gland metallothionein in shore crabs (Carcinus maenas) after exposure to cadmium in the food

    Energy Technology Data Exchange (ETDEWEB)

    Pedersen, Knud Ladegaard; Bach, Louise Thornhøj; Bjerregaard, Poul, E-mail: poul@biology.sdu.dk

    2014-05-01

    Highlights: • Crabs were fed with Cd in concentrations of 1.1–5.1 μg g⁻¹ food. • Metallothionein concentrations only increased at 5.1 μg g⁻¹. • Cd contents of metallothionein increased linearly with exposure. • A marked influence by the variable Cu contents on metal composition was recorded. • Digestive gland metallothionein is a poor biomarker for Cd exposure. - Abstract: Accumulation of cadmium in aquatic invertebrates may compromise human food safety and anthropogenic additions of cadmium to coastal areas cause concern. Induction of crustacean metallothionein has been suggested as a useful biomarker for contamination of the aquatic environment with cadmium. We investigated how exposure to low concentrations of cadmium in the food affects the subcellular binding of cadmium with the shore crab Carcinus maenas as model organism. Approximately 80% of the assimilated cadmium was bound in the soluble fraction of the midgut gland and of this, 82% was found in the metallothionein fraction. Metallothionein synthesis was only induced at the highest exposure level. However, the number of cadmium atoms bound per molecule of metallothionein increased linearly with exposure, from approximately 0.18 in the control group to 1.4 in a group administered food containing 5.1 μg Cd g⁻¹. We noted a marked interaction between the presence of copper and zinc in the midgut gland and the binding of cadmium. The usefulness of crustacean midgut gland metallothionein as a biomarker for cadmium exposure at modest levels was questioned since exposures at levels producing significant increases in the tissue contents of the metal did not result in elevated concentrations of metallothionein in the midgut gland.

  17. Induction by mercury compounds of brain metallothionein in rats: Hg{sup 0} exposure induces long-lived brain metallothionein

    Energy Technology Data Exchange (ETDEWEB)

    Yasutake, Akira; Nakano, Atsuhiro [Biochemistry Section, National Institute for Minamata Disease, Kumamoto (Japan); Hirayama, Kimiko [Kumamoto University, College of Medical Science (Japan)

    1998-03-01

    Metallothionein (MT) is one of the stress proteins which can easily be induced by various kind of heavy metals. However, MT in the brain is difficult to induce because of blood-brain barrier impermeability to most heavy metals. In this paper, we have attempted to induce brain MT in rats by exposure to methylmercury (MeHg) or metallic mercury vapor, both of which are known to penetrate the blood-brain barrier and cause neurological damage. Rats treated with MeHg (40 {mu}mol/kg per day x 5 days, p.o.) showed brain Hg levels as high as 18 {mu}g/g with slight neurological signs 10 days after final administration, but brain MT levels remained unchanged. However, rats exposed to Hg vapor for 7 days showed 7-8 {mu}g Hg/g brain tissue 24 h after cessation of exposure. At that time brain MT levels were about twice the control levels. Although brain Hg levels fell gradually with a half-life of 26 days, MT levels induced by Hg exposure remained unchanged for >2 weeks. Gel fractionation revealed that most Hg was in the brain cytosol fraction and thus bound to MT. Hybridization analysis showed that, despite a significant increase in MT-I and -II mRNA in brain, MT-III mRNA was less affected. Although significant Hg accumulation and MT induction were observed also in kidney and liver of Hg vapor-exposed rats, these decreased more quickly than in brain. The long-lived MT in brain might at least partly be accounted for by longer half-life of Hg accumulated there. The present results showed that exposure to Hg vapor might be a suitable procedure to provide an in vivo model with enhanced brain MT. (orig.) With 4 figs., 1 tab., 27 refs.

  18. Expression, purification of metallothionein genes from freshwater crab (Sinopotamon yangtsekiense) and development of an anti-metallothionein ELISA

    Science.gov (United States)

    Zhang, Hao; Zhou, Hui

    2017-01-01

    Using the phoA-fusion technology, the recombinant metallothionein (MT) from freshwater crab (Sinopotamon yangtsekiense) has been successfully produced in Escherichia coli. MT purified from the bacterial suspension showed one polypeptide with a molecular weight of 7 kDa by tricine-sodium dodecyl sulfate-polyacrylamide gel electrophoresis (Tricine-SDS-PAGE). Western-blotting confirmed the polypeptides had a specific reactivity with mouse polyclonal MT anti-serum. Based on the purified MT and MT anti-serum, the reaction parameters for an enzyme-linked immunosorbent assay (ELISA) were developed. The direct coating ELISA showed a higher linear relationship compared to antibody sandwich coating ELISA. The optimal dilution rates of purified MT anti-serum and coating period were shown to be 1:160,000 and 12 hours at 4°C. At 37°C, the appropriate reaction duration of the first antibody and the second antibody were 2 hours and 1 hour, respectively. According to these optimal parameters, the standard linear equation, y = 0.0032x + 0.1769 (R2 = 0.9779, x, y representing MT concentration and OD450 value), was established for the determination of MT concentration with a valid range of 3.9–500 ng/ml. In verification experiments, the mean coefficients of variation of the intra-assay and inter-assay were 3.260% and 3.736%, respectively. According to the result of MT recovery, ELISA with an approaching 100% MT recovery was more reliable and sensitive than the Cd saturation assay. In conclusion, the newly developed ELISA of this study was precise, stable and repeatable, and could be used as a biomarker tool to monitor pollution by heavy metals. PMID:28350826

  19. The aryl hydrocarbon receptor and glucocorticoid receptor interact to activate human metallothionein 2A

    Energy Technology Data Exchange (ETDEWEB)

    Sato, Shoko, E-mail: satosho@rs.tus.ac.jp [Laboratory of Nutrition, Graduate School of Agricultural Science, Tohoku University, Sendai 981-8555 (Japan); Shirakawa, Hitoshi, E-mail: shirakah@m.tohoku.ac.jp [Laboratory of Nutrition, Graduate School of Agricultural Science, Tohoku University, Sendai 981-8555 (Japan); Tomita, Shuhei, E-mail: tomita@med.tottori-u.ac.jp [Division of Molecular Pharmacology, Department of Pathophysiological and Therapeutic Science, Yonago 683-8503 (Japan); Tohkin, Masahiro, E-mail: tohkin@phar.nagoya-cu.ac.jp [Department of Medical Safety Science, Graduate School of Pharmaceutical Science, Nagoya City University, Nagoya 267-8603 (Japan); Gonzalez, Frank J., E-mail: gonzalef@mail.nih.gov [Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892 (United States); Komai, Michio, E-mail: mkomai@m.tohoku.ac.jp [Laboratory of Nutrition, Graduate School of Agricultural Science, Tohoku University, Sendai 981-8555 (Japan)

    2013-11-15

    Although the aryl hydrocarbon receptor (AHR) and glucocorticoid receptor (GR) play essential roles in mammalian development, stress responses, and other physiological events, crosstalk between these receptors has been the subject of much debate. Metallothioneins are classic glucocorticoid-inducible genes that were reported to increase upon treatment with AHR agonists in rodent tissues and cultured human cells. In this study, the mechanism of human metallothionein 2A (MT2A) gene transcription activation by AHR was investigated. Cotreatment with 3-methylcholanthrene and dexamethasone, agonists of AHR and GR respectively, synergistically increased MT2A mRNA levels in HepG2 cells. MT2A induction was suppressed by RNA interference against AHR or GR. Coimmunoprecipitation experiments revealed a physical interaction between AHR and GR proteins. Moreover, chromatin immunoprecipitation assays indicated that AHR was recruited to the glucocorticoid response element in the MT2A promoter. Thus, we provide a novel mechanism whereby AHR modulates expression of human MT2A via the glucocorticoid response element and protein–protein interactions with GR. - Highlights: • Aryl hydrocarbon receptor forms a complex with glucocorticoid receptor in cells. • Human metallothionein gene is regulated by the AHR and GR interaction. • AHR–GR complex binds to glucocorticoid response element in metallothionein gene. • We demonstrated a novel transcriptional mechanism via AHR and GR interaction.

  20. Unexpected Interactions of the Cyanobacterial Metallothionein SmtA with Uranium.

    Science.gov (United States)

    Acharya, Celin; Blindauer, Claudia A

    2016-02-15

    Molecules for remediating or recovering uranium from contaminated environmental resources are of high current interest, with protein-based ligands coming into focus recently. Metallothioneins either bind or redox-silence a range of heavy metals, conferring protection against metal stress in many organisms. Here, we report that the cyanobacterial metallothionein SmtA competes with carbonate for uranyl binding, leading to formation of heterometallic (UO2)(n)Zn4SmtA species, without thiol oxidation, zinc loss, or compromising secondary or tertiary structure of SmtA. In turn, only metalated and folded SmtA species were found to be capable of uranyl binding. (1)H NMR studies and molecular modeling identified Glu34/Asp38 and Glu12/C-terminus as likely adventitious, but surprisingly strong, bidentate binding sites. While it is unlikely that these interactions correspond to an evolved biological function of this metallothionein, their occurrence may offer new possibilities for designing novel multipurpose bacterial metallothioneins with dual ability to sequester both soft metal ions including Cu(+), Zn(2+), Cd(2+), Hg(2+), and Pb(2+) and hard, high-oxidation state heavy metals such as U(VI). The concomitant protection from the chemical toxicity of uranium may be valuable for the development of bacterial strains for bio-remediation.

  1. The aryl hydrocarbon receptor and glucocorticoid receptor interact to activate human metallothionein 2A

    International Nuclear Information System (INIS)

    Sato, Shoko; Shirakawa, Hitoshi; Tomita, Shuhei; Tohkin, Masahiro; Gonzalez, Frank J.; Komai, Michio

    2013-01-01

    Although the aryl hydrocarbon receptor (AHR) and glucocorticoid receptor (GR) play essential roles in mammalian development, stress responses, and other physiological events, crosstalk between these receptors has been the subject of much debate. Metallothioneins are classic glucocorticoid-inducible genes that were reported to increase upon treatment with AHR agonists in rodent tissues and cultured human cells. In this study, the mechanism of human metallothionein 2A (MT2A) gene transcription activation by AHR was investigated. Cotreatment with 3-methylcholanthrene and dexamethasone, agonists of AHR and GR respectively, synergistically increased MT2A mRNA levels in HepG2 cells. MT2A induction was suppressed by RNA interference against AHR or GR. Coimmunoprecipitation experiments revealed a physical interaction between AHR and GR proteins. Moreover, chromatin immunoprecipitation assays indicated that AHR was recruited to the glucocorticoid response element in the MT2A promoter. Thus, we provide a novel mechanism whereby AHR modulates expression of human MT2A via the glucocorticoid response element and protein–protein interactions with GR. - Highlights: • Aryl hydrocarbon receptor forms a complex with glucocorticoid receptor in cells. • Human metallothionein gene is regulated by the AHR and GR interaction. • AHR–GR complex binds to glucocorticoid response element in metallothionein gene. • We demonstrated a novel transcriptional mechanism via AHR and GR interaction

  2. Characterization of three distinct metallothionein genes of the Ag-hyperaccumulating ectomycorrhizal fungus Amanita strobiliformis

    Czech Academy of Sciences Publication Activity Database

    Hložková, K.; Matěnová, M.; Žáčková, P.; Strnad, Hynek; Hršelová, Hana; Hroudová, Miluše; Kotrba, P.

    2016-01-01

    Roč. 120, č. 3 (2016), s. 358-369 ISSN 1878-6146 R&D Projects: GA ČR(CZ) GAP504/11/0484 Institutional support: RVO:61388971 ; RVO:68378050 Keywords : Ectomycorrhizal fungi * Gene expression * Metal binding * Metallothionein Subject RIV: EB - Genetics ; Molecular Biology; EE - Microbiology, Virology (MBU-M) Impact factor: 2.184, year: 2016

  3. Intracellular sequestration of zinc, cadmium and silver in Hebeloma mesophaeum and characterization of its metallothionein genes

    Czech Academy of Sciences Publication Activity Database

    Sácký, J.; Leonhardt, T.; Borovička, Jan; Gryndler, Milan; Briksí, A.; Kotrba, P.

    2014-01-01

    Roč. 67, JUN (2014), s. 3-14 ISSN 1087-1845 R&D Projects: GA ČR(CZ) GAP504/11/0484 Institutional support: RVO:61388971 ; RVO:61389005 Keywords : mycorrhizal fungi * metal tolerance * hebeloma mesophaeum * compartmentalization * metallothionein Subject RIV: EB - Genetics ; Molecular Biology; EE - Microbiology, Virology (MBU-M) Impact factor: 2.587, year: 2014

  4. Determination of content of metallothionein and low molecular mass stress peptides in transgenic tobacco plants

    Czech Academy of Sciences Publication Activity Database

    Diopan, V.; Shestivska, V.; Adam, V.; Macek, Tomáš; Macková, M.; Havel, L.; Kizek, R.

    2008-01-01

    Roč. 94, č. 3 (2008), s. 291-298 ISSN 0167-6857 R&D Projects: GA MŠk 1M06030 Institutional research plan: CEZ:AV0Z40550506 Keywords : metallothionein * Nicotiana tabacum * thiols * phytoremediation Subject RIV: EI - Biotechnology ; Bionics Impact factor: 1.017, year: 2008

  5. Metallothionein Zn(2+)- and Cu(2+)-clusters from first-principles calculations

    DEFF Research Database (Denmark)

    Greisen, Per Junior; Jespersen, Jakob Berg; Kepp, Kasper Planeta

    2012-01-01

    Detailed electronic structures of Zn(ii) and Cu(ii) clusters from metallothioneins (MT) have been obtained using density functional theory (DFT), in order to investigate how oxidative stress-caused Cu(ii) intermediates affect Zn-binding to MT and cooperatively lead to Cu(i)MT. The inferred accura...

  6. Characterization of mercury bioremediation by transgenic bacteria expressing metallothionein and polyphosphate kinase

    Directory of Open Access Journals (Sweden)

    Gonzalez-Ruiz Gloriene

    2011-08-01

    Full Text Available Abstract Background The use of transgenic bacteria has been proposed as a suitable alternative for mercury remediation. Ideally, mercury would be sequestered by metal-scavenging agents inside transgenic bacteria for subsequent retrieval. So far, this approach has produced limited protection and accumulation. We report here the development of a transgenic system that effectively expresses metallothionein (mt-1 and polyphosphate kinase (ppk genes in bacteria in order to provide high mercury resistance and accumulation. Results In this study, bacterial transformation with transcriptional and translational enhanced vectors designed for the expression of metallothionein and polyphosphate kinase provided high transgene transcript levels independent of the gene being expressed. Expression of polyphosphate kinase and metallothionein in transgenic bacteria provided high resistance to mercury, up to 80 μM and 120 μM, respectively. Here we show for the first time that metallothionein can be efficiently expressed in bacteria without being fused to a carrier protein to enhance mercury bioremediation. Cold vapor atomic absorption spectrometry analyzes revealed that the mt-1 transgenic bacteria accumulated up to 100.2 ± 17.6 μM of mercury from media containing 120 μM Hg. The extent of mercury remediation was such that the contaminated media remediated by the mt-1 transgenic bacteria supported the growth of untransformed bacteria. Cell aggregation, precipitation and color changes were visually observed in mt-1 and ppk transgenic bacteria when these cells were grown in high mercury concentrations. Conclusion The transgenic bacterial system described in this study presents a viable technology for mercury bioremediation from liquid matrices because it provides high mercury resistance and accumulation while inhibiting elemental mercury volatilization. This is the first report that shows that metallothionein expression provides mercury resistance and

  7. Metallothionein - immunohistochemical cancer biomarker: a meta-analysis.

    Directory of Open Access Journals (Sweden)

    Jaromir Gumulec

    Full Text Available Metallothionein (MT has been extensively investigated as a molecular marker of various types of cancer. In spite of the fact that numerous reviews have been published in this field, no meta-analytical approach has been performed. Therefore, results of to-date immunohistochemistry-based studies were summarized using meta-analysis in this review. Web of science, PubMed, Embase and CENTRAL databases were searched (up to April 30, 2013 and the eligibility of individual studies and heterogeneity among the studies was assessed. Random and fixed effects model meta-analysis was employed depending on the heterogeneity, and publication bias was evaluated using funnel plots and Egger's tests. A total of 77 studies were included with 8,015 tissue samples (4,631 cases and 3,384 controls. A significantly positive association between MT staining and tumors (vs. healthy tissues was observed in head and neck (odds ratio, OR 9.95; 95% CI 5.82-17.03 and ovarian tumors (OR 7.83; 1.09-56.29, and a negative association was ascertained in liver tumors (OR 0.10; 0.03-0.30. No significant associations were identified in breast, colorectal, prostate, thyroid, stomach, bladder, kidney, gallbladder, and uterine cancers and in melanoma. While no associations were identified between MT and tumor staging, a positive association was identified with the tumor grade (OR 1.58; 1.08-2.30. In particular, strong associations were observed in breast, ovarian, uterine and prostate cancers. Borderline significant association of metastatic status and MT staining were determined (OR 1.59; 1.03-2.46, particularly in esophageal cancer. Additionally, a significant association between the patient prognosis and MT staining was also demonstrated (hazard ratio 2.04; 1.47-2.81. However, a high degree of inconsistence was observed in several tumor types, including colorectal, kidney and prostate cancer. Despite the ambiguity in some tumor types, conclusive results are provided in the tumors of

  8. The teratogenicity of cadmium-metallothionein in the rat

    International Nuclear Information System (INIS)

    Webb, M.; Holt, D.; Brown, N.; Hard, G.C.

    1988-01-01

    A single dose in the range 0.25-1.9 mg metallothionein-bound cadmium (MT-Cd)/kg body weight, when administered parenterally to the rat between day 8 and day 14 of gestation, is teratogenic. In vitro, the development of the isolated rat conceptus is unaffected by the addition of 1.5 μM MT-Cd to the culture medium whereas the same concentration of ionic Cd (as CdCl 2 ) is lethal. At short times after injection of 0.25 mg MT-Cd/kg body weight on gd 12, the maximal foetal and placental contents of Cd are low in comparison with those after a teratogenic dose of CdCl 2 and are of the same order as those in the embryo and placenta + yolk sac of the rat conceptus, cultured in the presence of the highest no-effect concentration of CdCl 2 . From this evidence, it is concluded that the uptake by the conceptus in vivo of either CdMT, or of Cd liberated therefrom, is unlikely to contribute to the teratogenic response. In the pregnant, as in the non-pregnant rat, the kidney appears to be the only organ that is affected directly by the metalloprotein. All doses in the range 0.25-1.0 mg MT-Cd/kg body weight are nephrotoxic and result in prolonged anorexia in the pregnant animal. While some of the foetal deformities that occur in the CdMT-dosed animal seem to be direct consequences of the renal dysfunction, others apparently are secondary to the maternal anorexia. In rats that are injected i.p on gd 12 with 0.25 mg MT-Cd/kg renal uptake of Cd is slower, but the final concentration is higher than in animals that are given the same dose i.v. At this and the higher dose levels structural and/or functional damage to the kidneys also is greater in i.p.-, than in i.v.-dosed animals. The incidence of foetal malformations, however, is similar in the i.p. and i.v. groups and varies little over the dose range. (orig./MG)

  9. Are metallothioneins equally good biomarkers of metal and oxidative stress?

    Science.gov (United States)

    Figueira, Etelvina; Branco, Diana; Antunes, Sara C; Gonçalves, Fernando; Freitas, Rosa

    2012-10-01

    Several researchers investigated the induction of metallothioneins (MTs) in the presence of metals, namely Cadmium (Cd). Fewer studies observed the induction of MTs due to oxidizing agents, and literature comparing the sensitivity of MTs to different stressors is even more scarce or even nonexistent. The role of MTs in metal and oxidative stress and thus their use as a stress biomarker, remains to be clearly elucidated. To better understand the role of MTs as a biomarker in Cerastoderma edule, a bivalve widely used as bioindicator, a laboratory assay was conducted aiming to assess the sensitivity of MTs to metal and oxidative stressors. For this purpose, Cd was used to induce metal stress, whereas hydrogen peroxide (H2O2), being an oxidizing compound, was used to impose oxidative stress. Results showed that induction of MTs occurred at very different levels in metal and oxidative stress. In the presence of the oxidizing agent (H2O2), MTs only increased significantly when the degree of oxidative stress was very high, and mortality rates were higher than 50 percent. On the contrary, C. edule survived to all Cd concentrations used and significant MTs increases, compared to the control, were observed in all Cd exposures. The present work also revealed that the number of ions and the metal bound to MTs varied with the exposure conditions. In the absence of disturbance, MTs bound most (60-70 percent) of the essential metals (Zn and Cu) in solution. In stressful situations, such as the exposure to Cd and H2O2, MTs did not bind to Cu and bound less to Zn. When organisms were exposed to Cd, the total number of ions bound per MT molecule did not change, compared to control. However the sort of ions bound per MT molecule differed; part of the Zn and all Cu ions where displaced by Cd ions. For organisms exposed to H2O2, each MT molecule bound less than half of the ions compared to control and Cd conditions, which indicates a partial oxidation of thiol groups in the cysteine

  10. JALUR MOLEKULER MEKANISME APOPTOSIS

    Directory of Open Access Journals (Sweden)

    Yani Corvianindya Rahayu

    2015-07-01

    Full Text Available Apoptosis or programmed cell death is a normal condition for development and live multicellular organism. Apoptosis is a morphological phenomenon that plays an important role in physiologic processes during fetal development and in adult. Mitochondria play an important role in apoptosis. Mitochondria can do apoptosis directly. Mitochondria has 2 family of protein Bcl-2. Bcl-2 and Bcl-XL are anti apoptosis while Bad an Bax are pro apoptosis. There are 3 different mechanism to receptors at the cell surface and a third may be triggered by dangerous agent that different from two ways before. Apoptosis also need caspase as cell death executor. Study of apoptosis still done especially in case of disease. Some disease have known related with disturbing of apoptosis mechanism for example cancer and auto immune. This article reviews about molecular mechanism of apoptosis for understanding disease and future therapy.

  11. Cytosolic labile zinc: a marker for apoptosis in the developing rat brain.

    Science.gov (United States)

    Lee, Joo-Yong; Hwang, Jung Jin; Park, Mi-Ha; Koh, Jae-Young

    2006-01-01

    Cytosolic zinc accumulation was thought to occur specifically in neuronal death (necrosis) following acute injury. However, a recent study demonstrated that zinc accumulation also occurs in adult rat neurons undergoing apoptosis following target ablation, and in vitro experiments have shown that zinc accumulation may play a causal role in various forms of apoptosis. Here, we examined whether intraneuronal zinc accumulation occurs in central neurons undergoing apoptosis during development. Embryonic and newborn Sprague-Dawley rat brains were double-stained for terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labelling (TUNEL) detection of apoptosis and immunohistochemical detection of stage-specific neuronal markers, such as nestin, proliferating cell nuclear antigen (PCNA), TuJ1 and neuronal nuclear specific protein (NeuN). The results revealed that apoptotic cell death occurred in neurons of diverse stages (neural stem cells, and dividing, young and adult neurons) throughout the brain during the embryonic and early postnatal periods. Further staining of brain sections with acid fuchsin or zinc-specific fluorescent dyes showed that all of the apoptotic neurons were acidophilic and contained labile zinc in their cell bodies. Cytosolic zinc accumulation was also observed in cultured cortical neurons undergoing staurosporine- or sodium nitroprusside (SNP)-induced apoptosis. In contrast, zinc chelation with CaEDTA or N,N,N',N'-tetrakis(2-pyridylmethyl)ethylenediamine (TPEN) reduced SNP-induced apoptosis but not staurosporine-induced apoptosis, indicating that cytosolic zinc accumulation does not play a causal role in all forms of apoptosis. Finally, the specific cytosolic zinc accumulation may have a practical application as a relatively simple marker for neurons undergoing developmental apoptosis.

  12. Electrochemical study of heavy metals and metallothionein in yeast Yarrowia lipolytica

    Czech Academy of Sciences Publication Activity Database

    Strouhal, M.; Kizek, René; Vacek, Jan; Trnková, L.; Němec, M.

    2003-01-01

    Roč. 60, 1-2 (2003), s. 29-36 ISSN 1567-5394 R&D Projects: GA AV ČR IAA4004110; GA ČR GA203/02/0422 Institutional research plan: CEZ:AV0Z5004920; CEZ:MSM 143100005 Keywords : electrochemical determination of metallothionein and heavy metals * yeast * Yarrowia lipolytica Subject RIV: BO - Biophysics Impact factor: 1.482, year: 2003

  13. Recombinational micro-evolution of functionally different metallothionein promoter alleles from Orchesella cincta

    Directory of Open Access Journals (Sweden)

    van Straalen Nico M

    2007-06-01

    Full Text Available Abstract Background Metallothionein (mt transcription is elevated in heavy metal tolerant field populations of Orchesella cincta (Collembola. This suggests that natural selection acts on transcriptional regulation of mt in springtails at sites where cadmium (Cd levels in soil reach toxic values This study investigates the nature and the evolutionary origin of polymorphisms in the metallothionein promoter (pmt and their functional significance for mt expression. Results We sequenced approximately 1600 bp upstream the mt coding region by genome walking. Nine pmt alleles were discovered in NW-European populations. They differ in the number of some indels, consensus transcription factor binding sites and core promoter elements. Extensive recombination events between some of the alleles can be inferred from the alignment. A deviation from neutral expectations was detected in a cadmium tolerant population, pointing towards balancing selection on some promoter stretches. Luciferase constructs were made from the most abundant alleles, and responses to Cd, paraquat (oxidative stress inducer and moulting hormone were studied in cell lines. By using paraquat we were able to dissect the effect of oxidative stress from the Cd specific effect, and extensive differences in mt induction levels between these two stressors were observed. Conclusion The pmt alleles evolved by a number of recombination events, and exhibited differential inducibilities by Cd, paraquat and molting hormone. In a tolerant population from a metal contaminated site, promoter allele frequencies differed significantly from a reference site and nucleotide polymorphisms in some promoter stretches deviated from neutral expectations, revealing a signature of balancing selection. Our results suggest that the structural differences in the Orchesella cincta metallothionein promoter alleles contribute to the metallothionein -over-expresser phenotype in cadmium tolerant populations.

  14. Smoking specifically induces metallothionein-2 isoform in human placenta at term

    International Nuclear Information System (INIS)

    Ronco, Ana Maria; Garrido, Fernando; Llanos, Miguel N.

    2006-01-01

    Recently, we reported the presence of higher levels of metallothionein (MT) in placentas of smokers compared to non-smokers. In the present study, we designed experiments to separate and evaluate two isoforms of MT (MT-1 and MT-2) in placentas of smokers and non-smokers. Metallothionein was extracted and separated by ion-exchange high performance liquid chromatography (HPLC), previous saturation with cadmium chloride. Two peaks eluting at 6 and 12.5 min, corresponding to MT-1 and MT-2, respectively, were obtained. Metallothionein present in both peaks was identified by Western blot analysis using a monoclonal antibody directed against MT-1 and MT-2. Each isoform concentration was calculated after measuring its cadmium content by atomic absorption spectrometry with inductively coupled-plasma. In placentas of smokers, MT-2 levels increased by seven-fold compared to non-smokers, whereas MT-1 was not changed. Total placental cadmium and zinc concentrations, determined by atomic absorption spectrometry and neutron activation analysis, respectively, were higher in smokers. Metallothioneins levels were clearly in excess to bind all cadmium ions present in placentas. However, most of placental zinc remains unbound to MTs, although as much as twice zinc ions could be bound to MT in smokers. In conclusion, MT-2 is the main isoform induced by smoking, suggesting that this isoform could be involved in placental cadmium and zinc retention. This fact, which could contribute to reduce the transference of zinc to the fetus, may be associated to detrimental effects on fetal growth and development

  15. Metallothionein response in earthworms Lampito mauritii (Kinberg) exposed to fly ash

    Energy Technology Data Exchange (ETDEWEB)

    Maity, S.; Hattacharya, S.; Chaudhury, S. [Visva Bharati, Santini Ketan (India)

    2009-10-15

    Among pollutants, the coal fly ash occupies a significant position in industrial wastes. The fly ash matrix is a complex mixture of various organic (polyhalogenated compounds) and inorganic (Si, Al, Fe, As, Cd, Bi, Hg, etc.) chemicals. The application of fly ash for agricultural purposes and as landfills may lead to the contamination of the land with some of the toxic chemical compounds present in fly ash. Thus prior to the application of fly ash for developmental activities, it requires bio-monitoring and risk characterization. In order to achieve this objective adult Lampito mauritii were exposed to different proportions of fly ash in soil for 30 d and the concentrations of metallothionein in earthworm were assessed. The results revealed that up to 50% of fly ash amendment does not apparently harm the earthworm in respect of their survival and growth. A significant increase in tissue metallothionein level was recorded in L mauritii exposed to fly ash amended soil without tissue metal accumulation indicating that metallothionein is involved in scavenging of free radicals and reactive oxygen species metabolites. It is concluded that this biochemical response observed in L mauritii exposed to fly ash amended soil could be used in ecotoxicological field monitoring.

  16. Metallothionein induction in aquatic oligochaete tubifex tubifex exposed to herbicide isoproturon.

    Science.gov (United States)

    Mosleh, Y Y; Paris-Palacios, S; Arnoult, F; Couderchet, M; Biagianti-Risbourg, S; Vernet, G

    2004-02-01

    Metallothioneins (MTs) are low-molecular-weight proteins mainly involved in metal ion detoxification. Recently it has been demonstrated that MTs participate in several cellular functions such as regulation of growth and antioxidative defenses. Moreover, pesticides can induce their synthesis. The aim of the current work was to determine the effects of isoproturon, either pure or formulated as Matin (suspension containing an isoproturon concentration of 500 g. L(-1)), on the metallothionein and total protein contents of the aquatic worm Tubifex tubifex. MT levels in exposed worms increased significantly after 7 and 15 days of exposure to a concentration of the herbicide of 50 mg. L(-1). Isoproturon reduced the metal (Cu, Zn, and Cd) content of metallothioneins, and it also increased the total protein content of the worms. These results suggest that MT induction may not be considered a specific biomarker of metal exposure but that it can be used as a nonspecific biomarker of the effect of isoproturon effect in aquatic worms. Copyright 2004 Wiley Periodicals, Inc. Environ Toxicol 19: 88-93, 2004.

  17. Identification of quantum dots labeled metallothionein by fast scanning laser-induced breakdown spectroscopy

    International Nuclear Information System (INIS)

    Konecna, Marie; Novotny, Karel; Krizkova, Sona; Blazkova, Iva; Kopel, Pavel; Kaiser, Jozef; Hodek, Petr; Kizek, Rene

    2014-01-01

    The technique described in this paper allows detection of quantum dots (QDs) specifically deposited on the polystyrene surface by laser-induced breakdown spectroscopy (LIBS). Using LIBS, the distribution of QDs or their conjugates with biomolecules deposited on the surface can be observed, regardless of the fact if they exhibit fluorescence or not. QDs deposited on the specific surface of polystyrene microplate in the form of spots are detected by determination of the metal included in the QDs structure. Cd-containing QDs (CdS, CdTe) stabilized with mercaptopropionic (MPA) or mercaptosuccinic (MSA) acid, respectively, alone or in the form of conjugates with metallothionein (MT) biomolecule are determined by using the 508.58 nm Cd emission line. The observed absolute detection limit for Cd in CdTe QDs conjugates with MT in one spot was 3 ng Cd. Due to the high sensitivity of this technique, the immunoanalysis in combination with LIBS was also investigated. Cd spatial distribution in sandwich immunoassay was detected. - Highlights: • We describe determination of biomolecules labeled with quantum dots by LIBS. • LIBS and immunoassay are applied for the determination of metallothionein. • Metallothionein amount detected by LIBS is 10-times lower compared to ELISA

  18. Identification of quantum dots labeled metallothionein by fast scanning laser-induced breakdown spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Konecna, Marie [Central European Institute of Technology, Brno University of Technology, Technicka 3058/10, CZ-616 00 Brno (Czech Republic); Department of Chemistry and Biochemistry, Faculty of Agronomy, Mendel University in Brno, Zemedelska 1, CZ-613 00 Brno (Czech Republic); Novotny, Karel [Central European Institute of Technology, Masaryk University, Kamenice 753/5, CZ-625 00 Brno (Czech Republic); Krizkova, Sona [Central European Institute of Technology, Brno University of Technology, Technicka 3058/10, CZ-616 00 Brno (Czech Republic); Department of Chemistry and Biochemistry, Faculty of Agronomy, Mendel University in Brno, Zemedelska 1, CZ-613 00 Brno (Czech Republic); Blazkova, Iva [Department of Chemistry and Biochemistry, Faculty of Agronomy, Mendel University in Brno, Zemedelska 1, CZ-613 00 Brno (Czech Republic); Kopel, Pavel [Central European Institute of Technology, Brno University of Technology, Technicka 3058/10, CZ-616 00 Brno (Czech Republic); Department of Chemistry and Biochemistry, Faculty of Agronomy, Mendel University in Brno, Zemedelska 1, CZ-613 00 Brno (Czech Republic); Kaiser, Jozef [Central European Institute of Technology, Brno University of Technology, Technicka 3058/10, CZ-616 00 Brno (Czech Republic); Institute of Physical Engineering, Brno University of Technology, Technicka 2, CZ-616 69 Brno (Czech Republic); Hodek, Petr [Department of Biochemistry, Faculty of Science, Charles University in Prague, Hlavova 2030/8, CZ-128 00 Prague,Czech Republic (Czech Republic); Kizek, Rene [Central European Institute of Technology, Brno University of Technology, Technicka 3058/10, CZ-616 00 Brno (Czech Republic); Department of Chemistry and Biochemistry, Faculty of Agronomy, Mendel University in Brno, Zemedelska 1, CZ-613 00 Brno (Czech Republic); and others

    2014-11-01

    The technique described in this paper allows detection of quantum dots (QDs) specifically deposited on the polystyrene surface by laser-induced breakdown spectroscopy (LIBS). Using LIBS, the distribution of QDs or their conjugates with biomolecules deposited on the surface can be observed, regardless of the fact if they exhibit fluorescence or not. QDs deposited on the specific surface of polystyrene microplate in the form of spots are detected by determination of the metal included in the QDs structure. Cd-containing QDs (CdS, CdTe) stabilized with mercaptopropionic (MPA) or mercaptosuccinic (MSA) acid, respectively, alone or in the form of conjugates with metallothionein (MT) biomolecule are determined by using the 508.58 nm Cd emission line. The observed absolute detection limit for Cd in CdTe QDs conjugates with MT in one spot was 3 ng Cd. Due to the high sensitivity of this technique, the immunoanalysis in combination with LIBS was also investigated. Cd spatial distribution in sandwich immunoassay was detected. - Highlights: • We describe determination of biomolecules labeled with quantum dots by LIBS. • LIBS and immunoassay are applied for the determination of metallothionein. • Metallothionein amount detected by LIBS is 10-times lower compared to ELISA.

  19. A novel perspective on neuron study: damaging and promoting effects in different neurons induced by mechanical stress.

    Science.gov (United States)

    Wang, Yazhou; Wang, Wei; Li, Zong; Hao, Shilei; Wang, Bochu

    2016-10-01

    A growing volume of experimental evidence demonstrates that mechanical stress plays a significant role in growth, proliferation, apoptosis, gene expression, electrophysiological properties and many other aspects of neurons. In this review, first, the mechanical microenvironment and properties of neurons under in vivo conditions are introduced and analyzed. Second, research works in recent decades on the effects of different mechanical forces, especially compression and tension, on various neurons, including dorsal root ganglion neurons, retinal ganglion cells, cerebral cortex neurons, hippocampus neurons, neural stem cells, and other neurons, are summarized. Previous research results demonstrate that mechanical stress can not only injure neurons by damaging their morphology, impacting their electrophysiological characteristics and gene expression, but also promote neuron self-repair. Finally, some future perspectives in neuron research are discussed.

  20. Trace metals and over-expression of metallothioneins in bladder tumoral lesions: a case-control study

    Directory of Open Access Journals (Sweden)

    Cymbron Teresa

    2009-07-01

    Full Text Available Abstract Background Previous studies have provided some evidence of a possible association between cancer and metallothioneins. Whether this relates to an exposure to carcinogenic metals remains unclear. Methods In order to examine the association between the expression of metallothioneins and bladder tumors, and to compare the levels of arsenic, cadmium, chromium, lead and nickel in animals with bladder tumors and animals without bladder tumors, 37 cases of bovine bladder tumors and 17 controls were collected. The detection and quantification of metallothioneins in bladder tissue of both cases and controls was performed by immunohistochemistry. And the quantification of metals in tissue and hair was assessed by inductively coupled plasma – mass spectrometry. Results Increased expression of metallothioneins was associated with bladder tumors when compared with non-tumoral bladder tissue (OR = 9.3, 95% CI: 1.0 – 480. The concentrations of cadmium, chromium, lead and nickel in hair of cases were significantly higher than those of controls. However, as for the concentration of metals in bladder tissue, the differences were not significant. Conclusion Though the sample size was small, the present study shows an association between bladder tumors and metallothioneins. Moreover, it shows that concentrations of metals such as cadmium, chromium, lead and nickel in hair may be used as a biomarker of exposure.

  1. [Effect of intermittent hypoxia of sleep apnea on embryonic rat cortical neurons in vitro].

    Science.gov (United States)

    Zhang, Chanjuan; Li, Yanzhong; Wang, Yan

    2015-05-01

    To investigate the effects of different pattens of intermittent hypoxia on the activity and apoptosis of primary cultured rat embryonic cortical neurons, and to evaluate the role of intermittent hypoxia in the mechanism of obstructive sleep syndrom induced cognitive function loss. The embryonic cerebral cortical neurons were cultured in vitro and were identified by immunofluorescence. Cultured neurons were randomly divided into intermittent hypoxia group, intermittent normal oxygen group, persistent hypoxia group and the control group, and intermittent hypoxia group was divided into five subgroups according to different frequency and time-bound. Neurons were exposed in different modes of hypoxia. MTT colorimetry was used to detect the viability of the neurons, and DAPI colorated measurement was used to calculate the percentages of neuron apoptosis. There were significantly different effects between all subgroups of intermittent hypoxia and the continued hypoxia group on neuronal activity and apoptosis (P Intermittent hypoxia groups with different frequency and time had no difference in neuronal activity and apoptosis (P > 0.05). The effect of intermittent hypoxia was more serious than that of continued hypoxia on neuronal activity and apoptosis; The impact of intermittent hypoxia on neuronal activity and apoptosis may be an important factor in obstructive sleep apnea related cognitive impairment.

  2. Mitochondrial dysfunction in lyssavirus-induced apoptosis.

    Science.gov (United States)

    Gholami, Alireza; Kassis, Raïd; Real, Eléonore; Delmas, Olivier; Guadagnini, Stéphanie; Larrous, Florence; Obach, Dorothée; Prevost, Marie-Christine; Jacob, Yves; Bourhy, Hervé

    2008-05-01

    Lyssaviruses are highly neurotropic viruses associated with neuronal apoptosis. Previous observations have indicated that the matrix proteins (M) of some lyssaviruses induce strong neuronal apoptosis. However, the molecular mechanism(s) involved in this phenomenon is still unknown. We show that for Mokola virus (MOK), a lyssavirus of low pathogenicity, the M (M-MOK) targets mitochondria, disrupts the mitochondrial morphology, and induces apoptosis. Our analysis of truncated M-MOK mutants suggests that the information required for efficient mitochondrial targeting and dysfunction, as well as caspase-9 activation and apoptosis, is held between residues 46 and 110 of M-MOK. We used a yeast two-hybrid approach, a coimmunoprecipitation assay, and confocal microscopy to demonstrate that M-MOK physically associates with the subunit I of the cytochrome c (cyt-c) oxidase (CcO) of the mitochondrial respiratory chain; this is in contrast to the M of the highly pathogenic Thailand lyssavirus (M-THA). M-MOK expression induces a significant decrease in CcO activity, which is not the case with M-THA. M-MOK mutations (K77R and N81E) resulting in a similar sequence to M-THA at positions 77 and 81 annul cyt-c release and apoptosis and restore CcO activity. As expected, the reverse mutations, R77K and E81N, introduced in M-THA induce a phenotype similar to that due to M-MOK. These features indicate a novel mechanism for energy depletion during lyssavirus-induced apoptosis.

  3. cDNA cloning and nucleotide sequence comparison of Chinese hamster metallothionein I and II mRNAs

    Energy Technology Data Exchange (ETDEWEB)

    Griffith, B B; Walters, R A; Enger, M D; Hildebrand, C E; Griffith, J K

    1983-01-01

    Polyadenylated RNA was extracted from a cadmium resistant Chinese hamster (CHO) cell line, enriched for metal-induced, abundant RNA sequences and cloned as double-stranded cDNA in the plasmid pBR322. Two cDNA clones, pCHMT1 and pCHMT2, encoding two Chinese hamster isometallothioneins were identified, and the nucleotide sequence of each insert was determined. The two Chinese hamster metallothioneins show nucleotide sequence homologies of 80% in the protein coding region and approximately 35% in both the 5' and 3' untranslated regions. Interestingly, an 8 nucleotide sequence (TGTAAATA) has been conserved in sequence and position in the 3' untranslated regions of each metallothionein mRNA sequenced thus far. Estimated nucleotide substitution rates derived from interspecies comparisons were used to calculate a metallothionein gene duplication time of 45 to 120 million years ago. 39 references, 1 figure, 1 table.

  4. Induction, regulation, degradation, and biological significance of mammalian metallothioneins.

    Science.gov (United States)

    Miles, A T; Hawksworth, G M; Beattie, J H; Rodilla, V

    2000-01-01

    MTs are small cysteine-rich metal-binding proteins found in many species and, although there are differences between them, it is of note that they have a great deal of sequence and structural homology. Mammalian MTs are 61 or 62 amino acid polypeptides containing 20 conserved cysteine residues that underpin the binding of metals. The existence of MT across species is indicative of its biological demand, while the conservation of cysteines indicates that these are undoubtedly central to the function of this protein. Four MT isoforms have been found so far, MT-1, MT-2, MT-3, and MT-4, but these also have subtypes with 17 MT genes identified in man, of which 10 are known to be functional. Different cells express different MT isoforms with varying levels of expression perhaps as a result of the different function of each isoform. Even different metals induce and bind to MTs to different extents. Over 40 years of research into MT have yielded much information on this protein, but have failed to assign to it a definitive biological role. The fact that multiple MT isoforms exist, and the great variety of substances and agents that act as inducers, further complicates the search for the biological role of MTs. This article reviews the current knowledge on the biochemistry, induction, regulation, and degradation of this protein in mammals, with a particular emphasis on human MTs. It also considers the possible biological roles of this protein, which include participation in cell proliferation and apoptosis, homeostasis of essential metals, cellular free radical scavenging, and metal detoxification.

  5. Induction of metallothionein(s) in organ-cultured duodenum: relationship to 1α,25-(OH)2-D3-induced CaBP synthesis

    International Nuclear Information System (INIS)

    Corradino, R.A.; Fullmer, C.S.; Frelier, E.; Maxwell, S.

    1979-01-01

    The embryonic chick duodenum contains no vitamin D-induced, calcium-binding protein (CaBP). However, when maintained in organ culture, the duodenum responds to 1α,25-(OH) 2 -D 3 in the culture medium by de novo synthesis of CaBP. Studies with this system have provided evidence that CaBP is directly involved in calcium transport at least at the mucosal surface. The present paper extends previous observations on the effects of the extremely toxic environmental pollutant, cadmium. Cadmium was found to inhibit 1α,25-(OH) 2 -D 3 -mediated responses in the organ-cultured duodenum, i.e., CaBP biosynthesis and 45 Ca uptake at the mucosal surface. Cadmium also stimulated concomitent production of a specific metallothionein (MT). Zinc had similar actions in inhibiting CaBP and stimulating Mt biosynthesis

  6. Screening of Cd tolerant genotypes and isolation of metallothionein genes in alfalfa (Medicago sativa L.)

    International Nuclear Information System (INIS)

    Wang Xiaojuan; Song, Yu; Ma Yanhua; Zhuo Renying; Jin Liang

    2011-01-01

    In order to evaluate Cd tolerance in wide-ranging sources of alfalfa (Medicago sativa) and to identify Cd tolerant genotypes which may potentially be useful for restoring Cd-contaminated environments, thirty-six accessions of alfalfa were screened under hydroponic culture. Our results showed that the relative root growth rate varied from 0.48 to 1.0, which indicated that different alfalfa accessions had various responses to Cd stress. The candidate fragments derived from differentially expressed metallothionein (MT) genes were cloned from leaves of two Cd tolerant genotypes, YE and LZ. DNA sequence and the deduced protein sequence showed that MsMT2a and MsMT2b had high similarity to those in leguminous plants. DDRT-PCR analysis showed that MsMT2a expressed in both YE and LZ plants under control and Cd stress treatment, but MsMT2b only expressed under Cd stress treatment. This suggested that MsMT2a was universally expressed in leaves of alfalfa but expression of MsMT2b was Cadmium (Cd) inducible. - Highlights: → Evaluate Cd tolerance in wide sources of alfalfa accessions. → Identify Cd-hyperaccumulators potentially useful for restoring Cd-contaminated environments. → Cloned differentially expressed metallothionein (MT) genes. → Characteristics and deduced protein sequence of MsMT2a and MsMT2b were analyzed. → MsMT2a might be a universally gene of alfalfa but MsMT2b might be an inductive gene. - Two Cd tolerant alfalfa genotypes were screened and their metallothionein genes were cloned which showed that MsMT2a was universally expressed but MsMT2b was Cd inducible expression.

  7. Cucumber Metallothionein-Like 2 (CsMTL2 Exhibits Metal-Binding Properties

    Directory of Open Access Journals (Sweden)

    Yu Pan

    2016-11-01

    Full Text Available We identified a novel member of the metallothionein (MT family, Cucumis sativus metallothionein-like 2 (CsMTL2, by screening a young cucumber fruit complementary DNA (cDNA library. The CsMTL2 encodes a putative 77-amino acid Class II MT protein that contains two cysteine (Cys-rich domains separated by a Cys-free spacer region. We found that CsMTL2 expression was regulated by metal stress and was specifically induced by Cd2+ treatment. We investigated the metal-binding characteristics of CsMTL2 and its possible role in the homeostasis and/or detoxification of metals by heterologous overexpression in Escherichia coli cells. Furthermore, we produced a deletion mutant form of the protein, CsMTL2m, that contained the two Cys-rich clusters but lacked the spacer region, in E. coli. We compared the metal-binding properties of CsMTL2 with those of CsMTL2m, the β domain of human metallothionein-like protein 1 (HsMTXb, and phytochelatin-like (PCL heterologously expressed in E. coli using metal-binding assays. We found that E. coli cells expressing CsMTL2 accumulated the highest levels of Zn2+ and Cd2+ of the four transformed cell types, with levels being significantly higher than those of control cells containing empty vector. E. coli cells expressing CsMTL2 had a higher tolerance for cadmium than for zinc ions. These findings show that CsMTL2 improves metal tolerance when heterologously expressed in E. coli. Future studies should examine whether CsMTL2 improves metal tolerance in planta.

  8. A cadmium metallothionein gene of ridgetail white prawn Exopalaemon carinicauda (Holthuis, 1950) and its expression

    Science.gov (United States)

    Zhang, Jiquan; Wang, Jing; Xiang, Jianhai

    2013-11-01

    Metallothioneins (MTs) are a group of low molecular weight cysteine-rich proteins capable of binding heavy metal ions. A cadmium metallothionein ( EcMT — Cd) cDNA with a 189 bp open reading frame (ORF) that encoded a 62 amino acid protein was obtained from Exopalaemon carinicauda. Seventeen cysteines were in the deduced amino acid sequence, and the cysteine (Cys)-rich characteristic was revealed in different metallothioneins in other species. In addition, the deduced amino acid sequence did not contain any aromatic amino acid residues, such as tyrosine (Tyr), tryptophan (Trp), and phenylalanine (Phe). EcMT—Cd mRNA was expressed in all tested tissues (the ovary, muscle, stomach, and hepatopancreas), and its expression profiles in the hepatopancreas were very different when shrimps were exposed to seawater containing either 50 μmol/L CuSO4 or 2.5 μmol/L CdCl 2. The expression of EcMT-Cd was significantly up-regulated in shrimp exposed to CuSO4 for 12 h and down-regulated in shrimps exposed to CdCl2 for 12 h. After 24 h exposure to both metals, its expression was down-regulated. By contrast, at 48 h the EcMT-Cd was up-regulated in test shrimps exposed to CdCl2. The transcript of EcMT-Cd was very low or even absent before the zoea stage, and the expression of EcMT-Cd was detected from mysis larvae-I, then its expression began to rise. In conclusion, a cadmium MT exists in E. carinicauda that is expressed in different tissues and during different developmental stages, and responds to the challenge with heavy metal ions, which provides a clue to understanding the function of cadmium MT.

  9. Screening of Cd tolerant genotypes and isolation of metallothionein genes in alfalfa (Medicago sativa L.)

    Energy Technology Data Exchange (ETDEWEB)

    Wang Xiaojuan, E-mail: xiaojuanwang@lzu.edu.cn [School of Pastoral Agriculture Science and Technology, Lanzhou University, P.O. Box 61, Lanzhou 730020 (China); Song, Yu [School of Pastoral Agriculture Science and Technology, Lanzhou University, P.O. Box 61, Lanzhou 730020 (China); Environment Management College of China, Qinhuangdao 066004 (China); Ma Yanhua [Hebei Normal University of Science and Technology, Qinhuangdao 066004 (China); Zhuo Renying [Key Lab of Tree Genomics, Research Institute of Subtropical of Forest, Chinese Academy of Forest, Fuyang 311400 (China); Jin Liang [School of Pastoral Agriculture Science and Technology, Lanzhou University, P.O. Box 61, Lanzhou 730020 (China)

    2011-12-15

    In order to evaluate Cd tolerance in wide-ranging sources of alfalfa (Medicago sativa) and to identify Cd tolerant genotypes which may potentially be useful for restoring Cd-contaminated environments, thirty-six accessions of alfalfa were screened under hydroponic culture. Our results showed that the relative root growth rate varied from 0.48 to 1.0, which indicated that different alfalfa accessions had various responses to Cd stress. The candidate fragments derived from differentially expressed metallothionein (MT) genes were cloned from leaves of two Cd tolerant genotypes, YE and LZ. DNA sequence and the deduced protein sequence showed that MsMT2a and MsMT2b had high similarity to those in leguminous plants. DDRT-PCR analysis showed that MsMT2a expressed in both YE and LZ plants under control and Cd stress treatment, but MsMT2b only expressed under Cd stress treatment. This suggested that MsMT2a was universally expressed in leaves of alfalfa but expression of MsMT2b was Cadmium (Cd) inducible. - Highlights: > Evaluate Cd tolerance in wide sources of alfalfa accessions. > Identify Cd-hyperaccumulators potentially useful for restoring Cd-contaminated environments. > Cloned differentially expressed metallothionein (MT) genes. > Characteristics and deduced protein sequence of MsMT2a and MsMT2b were analyzed. > MsMT2a might be a universally gene of alfalfa but MsMT2b might be an inductive gene. - Two Cd tolerant alfalfa genotypes were screened and their metallothionein genes were cloned which showed that MsMT2a was universally expressed but MsMT2b was Cd inducible expression.

  10. Metallothionein and heavy metals in daphnia pulex from Jose Antonio Alzate reservoir

    International Nuclear Information System (INIS)

    Avila Perez, P.; Zarazua Ortega, G.; Barcelo Quintal, D.; Rosas, I.; Diazdelgado, C.

    2001-01-01

    Water and specimens of the freshwater cladoceran Dhapnia pulex were collected at 4 different sites located in an area influenced by industrial, agricultural and urban activities in the Jose Antonio Alzate Reservoir in two different seasons. The Jose Antonio Alzate Reservoir fed by the Lerma river is the first significant water reservoir downstream of the main industrial areas in the State of Mexico. There are about 2,500 industrial discharges between the river source and the Alzate Reservoir which makes the Lerma river and the Jose Antonio Alzate Reservoir the most contaminated water bodies in the State of Mexico. The Monitoring National Network recognises these waters as highly contaminated, especially in the zone located between the Mexico-Toluca highway and the Alzate Reservoir. Water samples and freshwater cladoceran were analysed for Cu and Zn by Energy Dispersive X-Ray Fluorescence (EDXRF) and for Hg and Cd by Neutron Activation Analysis (NAA). As a general feature, the heavy metal concentrations of the water were found to decrease in the sequence: Cu > Zn > Hg > Cd. Metallothioneins (MT) were determined by silver saturation method. Tissue concentrations of MT in Dhapnia pulex varied between 5.69 and 8.96 (mg MT/ g wet wt) in rain season and between 48.87 and 74.00 (mg MT/ g wet wt) in dry season. Metallothioneins levels in Dhapnia pulex were significantly correlated (P < 0.01) with tissue Hg concentrations. In contrast, correlations between MT and tissue levels of Cu and Zn were weak. These observations suggest that Hg2+ activity is the key environmental factor to which metallothionein levels in Daphnia pulex are responding in the studied reservoir

  11. Metallothionein blocks oxidative DNA damage induced by acute inorganic arsenic exposure

    Energy Technology Data Exchange (ETDEWEB)

    Qu, Wei, E-mail: qu@niehs.nih.gov; Waalkes, Michael P.

    2015-02-01

    We studied how protein metallothionein (MT) impacts arsenic-induced oxidative DNA damage (ODD) using cells that poorly express MT (MT-I/II double knockout embryonic cells; called MT-null cells) and wild-type (WT) MT competent cells. Arsenic (as NaAsO{sub 2}) was less cytolethal over 24 h in WT cells (LC{sub 50} = 11.0 ± 1.3 μM; mean ± SEM) than in MT-null cells (LC{sub 50} = 5.6 ± 1.2 μM). ODD was measured by the immuno-spin trapping method. Arsenic (1 or 5 μM; 24 h) induced much less ODD in WT cells (121% and 141% of control, respectively) than in MT-null cells (202% and 260%). In WT cells arsenic caused concentration-dependent increases in MT expression (transcript and protein), and in the metal-responsive transcription factor-1 (MTF-1), which is required to induce the MT gene. In contrast, basal MT levels were not detectable in MT-null cells and unaltered by arsenic exposure. Transfection of MT-I gene into the MT-null cells markedly reduced arsenic-induced ODD levels. The transport genes, Abcc1 and Abcc2 were increased by arsenic in WT cells but either showed no or very limited increases in MT-null cells. Arsenic caused increases in oxidant stress defense genes HO-1 and GSTα2 in both WT and MT-null cells, but to much higher levels in WT cells. WT cells appear more adept at activating metal transport systems and oxidant response genes, although the role of MT in these responses is unclear. Overall, MT protects against arsenic-induced ODD in MT competent cells by potential sequestration of scavenging oxidant radicals and/or arsenic. - Highlights: • Metallothionein blocks arsenic toxicity. • Metallothionein reduces arsenic-induced DNA damage. • Metallothionein may bind arsenic or radicals produced by arsenic.

  12. Expression response of duplicated metallothionein 3 gene to copper stress in Silene vulgaris ecotypes

    Czech Academy of Sciences Publication Activity Database

    Nevrtalová, Eva; Baloun, Jiří; Hudzieczek, Vojtěch; Čegan, Radim; Vyskot, Boris; Doležel, Jaroslav; Šafář, Jan; Milde, D.; Hobza, Roman

    2014-01-01

    Roč. 251, č. 6 (2014), s. 1427-1439 ISSN 0033-183X R&D Projects: GA ČR(CZ) GAP501/12/2220; GA ČR(CZ) GBP501/12/G090; GA ČR(CZ) GP13-34962P; GA ČR(CZ) GA522/09/0083 Institutional support: RVO:68081707 Keywords : Copper * Gene duplication * Metallothionein Subject RIV: BO - Biophysics; EF - Botanics (UEB-Q) Impact factor: 2.651, year: 2014

  13. Alterations in radioresistance of eucaryotic cells after the transfer of genomic wildtype DNA and metallothionein genes

    International Nuclear Information System (INIS)

    Lohrer, H.

    1987-01-01

    The presented paper describes experiments concerning the alteration of radiosensitivity of eucaryotic cells after gene transfer. Ionizing radiation (γ- or X-ray) induces DNA single- or double strand breaks, which are religated by an unknown repair system. Repair deficient cells are highly sensitive to ionizing radiation. In the experiments described, cells from a patient with the heritable disease Ataxia telangiectasia were used as well as two X-ray sensitive CHO mutant cell lines. After gene transfer of an intact human DNA repair gene or a metallothionein gene the cells should regain radioresistance. (orig.) [de

  14. Apoptosis – is it good or bad?

    Directory of Open Access Journals (Sweden)

    Bakir Mehić

    2012-08-01

    induced by TNF-α. The over expression of antiapoptotic proteins may allow injured cells to survive, and autophagy may assist by providing critical metabolites. Apoptotic cells induce anergy or an immunosuppressive phenotype, whereas necrotic cells augment inflammation, in part by binding the receptor C-type lectin domain family 9 on dendritic cells.Clinical implications of apoptosis are consist in more than 50% of neoplasm’s that have defects in the apoptotic machinery mutations in the tumor-suppressor gene TP53, that is called the “guardian of the genome,” initiates apoptosis in response to DNA damage induced by radiation, chemical agents, oxidative stress, and other agents.[3] Abnormalities in apoptosis can increase susceptibility to autoimmune diseases.[4] There is growing evidence that neuronal apoptosis plays a key role in neonatal brain disorders.[5] Hepatocytes are particularly prone to apoptosis in response to various types of stress, including infections.[6] Necrosis predominates in ischemic injury, but often there are apoptotic cells in the hypoxic penumbra in myocardial infarction and stroke and in globally hypoxic zones after reperfusion injury. Sepsis is perhaps the most remarkable clinical setting in which apoptosis occurs. Massive apoptosis of immune effectors’ cells and gastrointestinal epithelial cells develops in patients with sepsis.[7] The profound loss of immune effectors’ cells in sepsis inhibits the ability of the immune system to eradicate the primary infection and renders the patient susceptible to nosocomial infections. Finally, why apoptosis is good? Because without apoptosis, 2 tons of bone marrow and lymph nodes and a 16-km intestine would probably accumulate in a human by the age of 8o.[8

  15. [Apoptosis and pathological process].

    Science.gov (United States)

    Rami, Mukhammed Salim Iusef

    2007-01-01

    Apoptosis (programmed cell death) occurs normally for maitenance of tissue homeostasis and play an important role in morphogenesis, embriogenesis and tissue growth. On the other hand, apoptosis may be involved in different pathological processes such as malignancy, infectious diseases and autoimmune disorders. Apoptosis is regulated by various mediators. Caspases, death receptors, mitochondria, Bcl-2 protoncogenes and tumor supressor genes are considered to be the most important of them. Advance in apoptosis regulation research suggests enormouse facilities for therapy of wide range of human illnesses.

  16. Motor Neurons

    DEFF Research Database (Denmark)

    Hounsgaard, Jorn

    2017-01-01

    Motor neurons translate synaptic input from widely distributed premotor networks into patterns of action potentials that orchestrate motor unit force and motor behavior. Intercalated between the CNS and muscles, motor neurons add to and adjust the final motor command. The identity and functional...... in in vitro preparations is far from complete. Nevertheless, a foundation has been provided for pursuing functional significance of intrinsic response properties in motoneurons in vivo during motor behavior at levels from molecules to systems....

  17. A Simple Metallothionein-Based Biosensor for Enhanced Detection of Arsenic and Mercury

    Directory of Open Access Journals (Sweden)

    Gordon W. Irvine

    2017-03-01

    Full Text Available Metallothioneins (MTs are a family of cysteine-rich proteins whose biological roles include the regulation of essential metal ions and protection against the harmful effects of toxic metals. Due to its high affinity for many toxic, soft metals, recombinant human MT isoform 1a was incorporated into an electrochemical-based biosensor for the detection of As3+ and Hg2+. A simple design was chosen to maximize its potential in environmental monitoring and MT was physically adsorbed onto paper discs placed on screen-printed carbon electrodes (SPCEs. This system was tested with concentrations of arsenic and mercury typical of contaminated water sources ranging from 5 to 1000 ppb. The analytical performance of the MT-adsorbed paper discs on SPCEs demonstrated a greater than three-fold signal enhancement and a lower detection limit compared to blank SPCEs, 13 ppb for As3+ and 45 ppb for Hg2+. While not being as low as some of the recommended drinking water limits, the sensitivity of the simple MT-biosensor would be potentially useful in monitoring of areas of concern with a known contamination problem. This paper describes the ability of the metal binding protein metallothionein to enhance the effectiveness of a simple, low-cost electrochemical sensor.

  18. Overexpressed human metallothionein IIA gene protects Chinese hamster ovary cells from killing by alkylating agents

    International Nuclear Information System (INIS)

    Kaina, B.; Lohrer, H.; Karin, M.; Herrlich, P.

    1990-01-01

    Experiments were designed to detect survival advantages that cells gain by overexpressing metallothionein (MT). Chinese hamster ovary K1-2 cells and an x-ray-sensitive derivative were transfected with a bovine papillomavirus (BPV)-linked construct carrying the human metallothionein IIA (hMT-IIA) gene. Transfectants survived 40-fold higher levels of cadmium chloride, harbored at least 30 copies of hMT-IIA, and contained 25- to 166-fold more MT than the parent cells. Even under conditions of reduced glutathione synthesis, the transfectants were not more resistant to the lethal effects of ionizing radiation and bleomycin than the parent cells. Thus free radicals generated by these agents cannot be scavenged efficiently by MT in vivo. The hMT-IIA transfectants, however, but not control transfectants harboring a BPV-MT promoter-neo construct, tolerated significantly higher doses of the alkylating agents N-methyl-N-nitrosourea and N-methyl-N'-nitro-N-nitrosoguanidine. Resistance and MT overexpression occurred irrespective of selection and cultivation in cadmium and zinc. There was no increase in resistance to methyl methanesulfonate and N-hydroxyethyl-N-chloroethylnitrosourea. MT did not affect the degree of overall DNA methylation after N-methyl-N-nitrosourea treatment nor the level of O6-methylguanine-DNA methyltransferase. The results suggest that MT participates as a cofactor or regulatory element in repair or tolerance of toxic alkylation lesions

  19. Responses of wild small mammals to a pollution gradient: Host factors influence metal and metallothionein levels

    International Nuclear Information System (INIS)

    Fritsch, Clementine; Cosson, Richard P.; Coeurdassier, Michael; Raoul, Francis; Giraudoux, Patrick; Crini, Nadia; Vaufleury, Annette de; Scheifler, Renaud

    2010-01-01

    We investigated how host factors (species, age, gender) modulated Cd, Pb, Zn, and Cu concentrations, metallothionein levels (MTs) and their relationships in 7 sympatric small mammal species along a pollution gradient. Cd concentrations in liver and kidneys increased with age in all species. Age effect on other metals and MTs differs among species. Gender did not influence metal and MT levels except in the bank vole. Three patterns linking internal metal concentrations and MTs were observed along the gradient: a low metal accumulation with a (i) high (wood mouse) or (ii) low (bank vole) level of MTs accompanied by a slight or no increase of MTs with Cd accumulation; (iii) an elevated metal accumulation with a sharp increase of MTs (common and pygmy shrews). In risk assessment and biomonitoring perspectives, we conclude that measurements of MTs and metals might be associated because they cannot be interpreted properly when considered separately. - Age more than gender and species more than trophic group influence metallic trace element and metallothionein levels and their relationships in wild small mammals exposed to metals.

  20. The Metallothionein Gene, TaMT3, from Tamarix androssowii Confers Cd2+ Tolerance in Tobacco

    Directory of Open Access Journals (Sweden)

    Boru Zhou

    2014-06-01

    Full Text Available Cadmium (Cd is a nonessential microelement and low concentration Cd2+ has strong toxicity to plant growth. Plant metallothioneins, a class of low molecular, cystein(Cys-rich and heavy-metal binding proteins, play an important role in both metal chaperoning and scavenging of reactive oxygen species (ROS with their large number of cysteine residues and therefore, protect plants from oxidative damage. In this study, a metallothionein gene, TaMT3, isolated from Tamarix androssowii was transformed into tobacco (Nicotiana tobacum through Agrobacterium-mediated leaf disc method, and correctly expressed under the control of 35S promoter. Under Cd2+ stress, the transgenic tobacco showed significant increases of superoxide dismutase (SOD activity and chlorophyll concentration, but decreases of peroxidase (POD activity and malondialdehyde (MDA accumulation when compared to the non-transgenic tobacco. Vigorous growth of transgenic tobacco was observed at the early development stages, resulting in plant height and fresh weight were significantly larger than those of the non-transgenic tobacco under Cd2+ stress. These results demonstrated that the expression of the exogenous TaMT3 gene increased the ability of ROS cleaning-up, indicating a stronger tolerance to Cd2+ stress.

  1. The metallothionein gene, TaMT3, from Tamarix androssowii confers Cd2+ tolerance in tobacco.

    Science.gov (United States)

    Zhou, Boru; Yao, Wenjing; Wang, Shengji; Wang, Xinwang; Jiang, Tingbo

    2014-06-10

    Cadmium (Cd) is a nonessential microelement and low concentration Cd2+ has strong toxicity to plant growth. Plant metallothioneins, a class of low molecular, cystein(Cys)-rich and heavy-metal binding proteins, play an important role in both metal chaperoning and scavenging of reactive oxygen species (ROS) with their large number of cysteine residues and therefore, protect plants from oxidative damage. In this study, a metallothionein gene, TaMT3, isolated from Tamarix androssowii was transformed into tobacco (Nicotiana tobacum) through Agrobacterium-mediated leaf disc method, and correctly expressed under the control of 35S promoter. Under Cd2+ stress, the transgenic tobacco showed significant increases of superoxide dismutase (SOD) activity and chlorophyll concentration, but decreases of peroxidase (POD) activity and malondialdehyde (MDA) accumulation when compared to the non-transgenic tobacco. Vigorous growth of transgenic tobacco was observed at the early development stages, resulting in plant height and fresh weight were significantly larger than those of the non-transgenic tobacco under Cd2+ stress. These results demonstrated that the expression of the exogenous TaMT3 gene increased the ability of ROS cleaning-up, indicating a stronger tolerance to Cd2+ stress.

  2. Dietary supplementation of blueberry juice enhances hepatic expression of metallothionein and attenuates liver fibrosis in rats.

    Directory of Open Access Journals (Sweden)

    Yuping Wang

    Full Text Available To investigate the effect of blueberry juice intake on rat liver fibrosis and its influence on hepatic antioxidant defense.Rabbiteye blueberry was used to prepare fresh juice to feed rats by daily gastric gavage. Dan-shao-hua-xian capsule (DSHX was used as a positive control for liver fibrosis protection. Liver fibrosis was induced in male Sprague-Dawley rats by subcutaneous injection of CCl4 and feeding a high-lipid/low-protein diet for 8 weeks. Hepatic fibrosis was evaluated by Masson staining. The expression of α-smooth muscle actin (α-SMA and collagen III (Col III were determined by immunohistochemical techniques. The activities of superoxide dismutase (SOD and malondialdehyde (MDA in liver homogenates were determined. Metallothionein (MT expression was detected by real-time RT-PCR and immunohistochemical techniques.Blueberry juice consumption significantly attenuates CCl4-induced rat hepatic fibrosis, which was associated with elevated expression of metallothionein (MT, increased SOD activity, reduced oxidative stress, and decreased levels of α-SMA and Col III in the liver.Our study suggests that dietary supplementation of blueberry juice can augment antioxidative capability of the liver presumably via stimulating MT expression and SOD activity, which in turn promotes HSC inactivation and thus decreases extracellular matrix collagen accumulation in the liver, and thereby alleviating hepatic fibrosis.

  3. Dietary Supplementation of Blueberry Juice Enhances Hepatic Expression of Metallothionein and Attenuates Liver Fibrosis in Rats

    Science.gov (United States)

    Wang, Yuping; Cheng, Mingliang; Zhang, Baofang; Nie, Fei; Jiang, Hongmei

    2013-01-01

    Aim To investigate the effect of blueberry juice intake on rat liver fibrosis and its influence on hepatic antioxidant defense. Methods Rabbiteye blueberry was used to prepare fresh juice to feed rats by daily gastric gavage. Dan-shao-hua-xian capsule (DSHX) was used as a positive control for liver fibrosis protection. Liver fibrosis was induced in male Sprague-Dawley rats by subcutaneous injection of CCl4 and feeding a high-lipid/low-protein diet for 8 weeks. Hepatic fibrosis was evaluated by Masson staining. The expression of α-smooth muscle actin (α-SMA) and collagen III (Col III) were determined by immunohistochemical techniques. The activities of superoxide dismutase (SOD) and malondialdehyde (MDA) in liver homogenates were determined. Metallothionein (MT) expression was detected by real-time RT-PCR and immunohistochemical techniques. Results Blueberry juice consumption significantly attenuates CCl4-induced rat hepatic fibrosis, which was associated with elevated expression of metallothionein (MT), increased SOD activity, reduced oxidative stress, and decreased levels of α-SMA and Col III in the liver. Conclusion Our study suggests that dietary supplementation of blueberry juice can augment antioxidative capability of the liver presumably via stimulating MT expression and SOD activity, which in turn promotes HSC inactivation and thus decreases extracellular matrix collagen accumulation in the liver, and thereby alleviating hepatic fibrosis. PMID:23554912

  4. INTRODUKSI GEN METALLOTHIONEIN TIPE II KE DALAM RUMPUT LAUT Kappaphycus alvarezii MENGGUNAKAN Agrobacterium tumefaciens

    Directory of Open Access Journals (Sweden)

    Ulia Fajriah

    2014-12-01

    Full Text Available Kappaphycus alvarezii adalah jenis alga merah yang memproduksi kappa karagenan yang sangat penting untuk industri makanan, farmasi, dan kosmetik. Untuk meningkatkan produksi, diperlukan ketersediaan bahan baku yang baik. Salah satu yang memengaruhi ketersediaan bahan baku adalah kondisi ingkungan perairan untuk budidaya. Metallothionein (MT adalah protein yang memiliki kemampuan untuk mengikat ion logam seperti Cd, Zn, dan Cu. Tujuan penelitian ini adalah untuk mengintroduksi gen Metallothionein Tipe II (MaMt2 ke dalam genom K. alvarezii menggunakan Agrobacterium tumefaciens. Talus rumput laut diinokulasi dengan A. tumefaciens mengandung plasmid pIG6-SMt2 yang membawa gen MaMt2, selanjutnya dilakukan seleksi bertingkat menggunakan higromisin 10 mg/L dan 20 mg/L. Hasil efisiensi transformasi yang diperoleh adalah 27,4%, efisiensi regenerasi tunas transgenik adalah 27,6%. Analisis molekuler dengan PCR menunjukkan bahwa 13 tunas transgenik mengandung gen MaMt2. Tunas transgenik putatif ditumbuhkan hingga menjadi talus baru dan dapat dilakukan uji tantang pada penelitian selanjutnya.

  5. Overexpressed human metallothionein IIA gene protects Chinese hamster ovary cells from killing by alkylating agents

    Energy Technology Data Exchange (ETDEWEB)

    Kaina, B.; Lohrer, H.; Karin, M.; Herrlich, P. (Kernforschungszentrum Karlsruhe, Karlsruhe (Germany, F.R.))

    1990-04-01

    Experiments were designed to detect survival advantages that cells gain by overexpressing metallothionein (MT). Chinese hamster ovary K1-2 cells and an x-ray-sensitive derivative were transfected with a bovine papillomavirus (BPV)-linked construct carrying the human metallothionein IIA (hMT-IIA) gene. Transfectants survived 40-fold higher levels of cadmium chloride, harbored at least 30 copies of hMT-IIA, and contained 25- to 166-fold more MT than the parent cells. Even under conditions of reduced glutathione synthesis, the transfectants were not more resistant to the lethal effects of ionizing radiation and bleomycin than the parent cells. Thus free radicals generated by these agents cannot be scavenged efficiently by MT in vivo. The hMT-IIA transfectants, however, but not control transfectants harboring a BPV-MT promoter-neo construct, tolerated significantly higher doses of the alkylating agents N-methyl-N-nitrosourea and N-methyl-N'-nitro-N-nitrosoguanidine. Resistance and MT overexpression occurred irrespective of selection and cultivation in cadmium and zinc. There was no increase in resistance to methyl methanesulfonate and N-hydroxyethyl-N-chloroethylnitrosourea. MT did not affect the degree of overall DNA methylation after N-methyl-N-nitrosourea treatment nor the level of O6-methylguanine-DNA methyltransferase. The results suggest that MT participates as a cofactor or regulatory element in repair or tolerance of toxic alkylation lesions.

  6. Overexpressed human metallothionein IIA gene protects Chinese hamster ovary cells from killing by alkylating agents.

    Science.gov (United States)

    Kaina, B; Lohrer, H; Karin, M; Herrlich, P

    1990-01-01

    Experiments were designed to detect survival advantages that cells gain by overexpressing metallothionein (MT). Chinese hamster ovary K1-2 cells and an x-ray-sensitive derivative were transfected with a bovine papillomavirus (BPV)-linked construct carrying the human metallothionein IIA (hMT-IIA) gene. Transfectants survived 40-fold higher levels of cadmium chloride, harbored at least 30 copies of hMT-IIA, and contained 25- to 166-fold more MT than the parent cells. Even under conditions of reduced glutathione synthesis, the transfectants were not more resistant to the lethal effects of ionizing radiation and bleomycin than the parent cells. Thus free radicals generated by these agents cannot be scavenged efficiently by MT in vivo. The hMT-IIA transfectants, however, but not control transfectants harboring a BPV-MT promoter-neo construct, tolerated significantly higher doses of the alkylating agents N-methyl-N-nitrosourea and N-methyl-N'-nitro-N-nitrosoguanidine. Resistance and MT overexpression occurred irrespective of selection and cultivation in cadmium and zinc. There was no increase in resistance to methyl methanesulfonate and N-hydroxyethyl-N-chloroethylnitrosourea. MT did not affect the degree of overall DNA methylation after N-methyl-N-nitrosourea treatment nor the level of O6-methylguanine-DNA methyltransferase. The results suggest that MT participates as a cofactor or regulatory element in repair or tolerance of toxic alkylation lesions. Images PMID:2320583

  7. Neuron-derived IgG protects neurons from complement-dependent cytotoxicity.

    Science.gov (United States)

    Zhang, Jie; Niu, Na; Li, Bingjie; McNutt, Michael A

    2013-12-01

    Passive immunity of the nervous system has traditionally been thought to be predominantly due to the blood-brain barrier. This concept must now be revisited based on the existence of neuron-derived IgG. The conventional concept is that IgG is produced solely by mature B lymphocytes, but it has now been found to be synthesized by murine and human neurons. However, the function of this endogenous IgG is poorly understood. In this study, we confirm IgG production by rat cortical neurons at the protein and mRNA levels, with 69.0 ± 5.8% of cortical neurons IgG-positive. Injury to primary-culture neurons was induced by complement leading to increases in IgG production. Blockage of neuron-derived IgG resulted in more neuronal death and early apoptosis in the presence of complement. In addition, FcγRI was found in microglia and astrocytes. Expression of FcγR I in microglia was increased by exposure to neuron-derived IgG. Release of NO from microglia triggered by complement was attenuated by neuron-derived IgG, and this attenuation could be reversed by IgG neutralization. These data demonstrate that neuron-derived IgG is protective of neurons against injury induced by complement and microglial activation. IgG appears to play an important role in maintaining the stability of the nervous system.

  8. Radiation-induced apoptosis

    International Nuclear Information System (INIS)

    Ohyama, Harumi

    1995-01-01

    Apoptosis is an active process of gene-directed cellular self-destruction that can be induced in many cell types via numerous physiological and pathological stimuli. We found that interphasedeath of thymocytes is a typical apoptosis showing the characteristic features of apoptosis including cell shrinkage, chromatin condensation and DNA degradation. Moderate dose of radiation induces extensive apoptosis in rapidly proliferating cell population such as the epithelium of intestinal crypt. Recent reports indicate that the ultimate form of radiation-induced mitotic death in several cells is also apoptosis. One of the hallmarks of apoptosis is the enzymatic internucleosomal degradation of chromatin DNA. We identified an endonuclease responsible for the radiation-induced DNA degradation in rat thymocytes. The death-sparing effects of interrupting RNA and protein synthesis suggested a cell genetic program for apoptosis. Apoptosis of thymocytes initiated by DNA damage, such as radiation and radio mimetic substance, absolutely requires the protein of p53 cancer suppresser gene. The cell death induced by glucocorticoid, or aging, has no such requirement. Expression of oncogene bcl-2 rescues cells from the apoptosis. Massive apoptosis in radiosensitive cells induced by higher dose radiation may be fatal. It is suggested that selective apoptotic elimination of cells would play an important role for protection against carcinogenesis and malformation through removal of cells with unrepaired radiation-induced DNA damages. Data to evaluate the significance of apoptosis in the radiation risk are still poor. Further research should be done in order to clarify the roles of the cell death on the acute and late effects of irradiation. (author)

  9. Effect of recombinant human erythropoietin expressions of apoptosis ...

    African Journals Online (AJOL)

    apoptosis genes in rats following traumatic brain injury. Xuesong Yuan1* ... ĸB)-, c-myc-, and Fas/Fasl-positive cells were identified in brain tissues by ... stem cells present in the bone marrow. ... neuronal regeneration [12], lowering toxicity of.

  10. Time-course expression of CNS inflammatory, neurodegenerative tissue repair markers and metallothioneins during experimental autoimmune encephalomyelitis

    DEFF Research Database (Denmark)

    Espejo, C; Penkowa, M; Demestre, M

    2005-01-01

    -inflammatory, neuroprotective, antioxidant proteins expressed during EAE and MS, in which they might play a protective role. The present study aimed to describe the expression profile of a group of inflammatory, neurodegenerative and tissue repair markers as well as metallothioneins during proteolipid protein-induced EAE...

  11. A Plasmid Containing the Human Metallothionein II Gene Can Function as an Antibody-assisted Electrophoretic Biosensor for Heavy Metals

    Science.gov (United States)

    2015-01-16

    Biol. Chem. 273:7127–7133. Brugnera, E., Georgiev, O., Radtke , F., et al. 1994. Cloning, chromosomal mapping and characterization of the human metal...Signaling events for metallothionein induction. Mutat. Res. 533:211–226. Heuchel, R., Radtke , F., Georgiev, O., et al. 1994. The transcription factor MTF

  12. Comparison of Metallothionein Detection by Using Brdicka Reaction and Enzyme-Linked Immunosorbent Assay Employing Chicken Yolk Antibodies

    Czech Academy of Sciences Publication Activity Database

    Křížková, S.; Bláhová, P.; Nakielna, J.; Fabrik, I.; Adam, V.; Eckschlager, T.; Beklová, M.; Svobodová, Z.; Horák, Vratislav; Krížek, R.

    2009-01-01

    Roč. 21, č. 23 (2009), s. 2575-2583 ISSN 1040-0397 Institutional research plan: CEZ:AV0Z50450515 Keywords : Metallothionein * Differential pulse voltammetry * ELISA Subject RIV: CG - Electrochemistry Impact factor: 2.630, year: 2009

  13. Ubiquitination in apoptosis signaling

    NARCIS (Netherlands)

    van de Kooij, L.W.

    2014-01-01

    The work described in this thesis focuses on ubiquitination and protein degradation, with an emphasis on how these processes regulate apoptosis signaling. More specifically, our aims were: 1. To increase the understanding of ubiquitin-mediated regulation of apoptosis signaling. 2. To identify the E3

  14. Hyperthermia-induced apoptosis

    NARCIS (Netherlands)

    Nijhuis, E.H.A.

    2008-01-01

    This thesis describes a number of studies that investigated several aspects of heat-induced apoptosis in human lymphoid malignancies. Cells harbour both pro- and anti-apoptotic proteins and the balance between these proteins determines whether a cell is susceptible to undergo apoptosis. In this

  15. Apoptosis in the eye.

    OpenAIRE

    Chahory , Sabine; Torriglia , Alicia

    2006-01-01

    Apoptosis is a normal component of the development and health of multicellular organisms. Cells die during apoptosis in a controlled, regulated fashion. This form of cell death is very important in eye development as well as in eye pathology. We review in this chapter our current knowledge in this topic.

  16. Paeoniflorin, a Monoterpene Glycoside, Protects the Brain from Cerebral Ischemic Injury via Inhibition of Apoptosis.

    Science.gov (United States)

    Zhang, Yuqin; Li, Huang; Huang, Mingqing; Huang, Mei; Chu, Kedan; Xu, Wei; Zhang, Shengnan; Que, Jinhua; Chen, Lidian

    2015-01-01

    Paeoniflorin (PF) is a principal bioactive component, which exhibits many pharmacological effects, including protection against ischemic injury. This paper aimed to investigate the protective effect of PF both in vivo and in vitro. Middle cerebral artery occlusion (MCAO) was performed on male Sprague-Dawley (SD) rat for 2 h, and different doses of PF or vehicle were administered 2 h after reperfusion. Rats were sacrificed after 7 days treatment of PF/vehicle. PF treatment for 7 days ameliorated MCAO-induced neurological deficit and decreased the infarct area. Further study demonstrated that PF inhibited the over-activation of astrocytes and apoptosis of neurons, and PF promoted up-regulation of neuronal specific marker neuron-specific nuclear (NeuN) and microtubule-associated protein 2 (MAP-2) in brain. Moreover, NMDA-induced neuron apoptosis was employed. The in vitro study revealed that PF treatment protected against NMDA-induced cell apoptosis and neuronal loss via up-regulation of neuronal specific marker NeuN, MAP-2 and Bcl-2 and the down-regulation Bax. Taken together, the present study demonstrates that PF produces its protective effect by inhibiting the over-activation of astrocytes, apoptosis of neurons and up-regulation of neuronal specific marker NeuN, MAP-2, and B-cell lymphoma-2 (Bcl-2), and down-regulation Bax. Our study reveals that PF may be a potential neuroprotective agent for stroke and can provide basic data for clinical use.

  17. [Mirror neurons].

    Science.gov (United States)

    Rubia Vila, Francisco José

    2011-01-01

    Mirror neurons were recently discovered in frontal brain areas of the monkey. They are activated when the animal makes a specific movement, but also when the animal observes the same movement in another animal. Some of them also respond to the emotional expression of other animals of the same species. These mirror neurons have also been found in humans. They respond to or "reflect" actions of other individuals in the brain and are thought to represent the basis for imitation and empathy and hence the neurobiological substrate for "theory of mind", the potential origin of language and the so-called moral instinct.

  18. Cell Cycle Deregulation in the Neurons of Alzheimer’s Disease

    Science.gov (United States)

    Moh, Calvin; Kubiak, Jacek Z.; Bajic, Vladan P.; Zhu, Xiongwei; Smith, Mark A.

    2018-01-01

    The cell cycle consists of four main phases: G1, S, G2, and M. Most cells undergo these cycles up to 40–60 times in their life. However, neurons remain in a nondividing, nonreplicating phase, G0. Neurons initiate but do not complete cell division, eventually entering apoptosis. Research has suggested that like cancer, Alzheimer’s disease (AD) involves dysfunction in neuronal cell cycle reentry, leading to the development of the two-hit hypothesis of AD. The first hit is abnormal cell cycle reentry, which typically results in neuronal apoptosis and prevention of AD. However, with the second hit of chronic oxidative damage preventing apoptosis, neurons gain “immortality” analogous to tumor cells. Once both of these hits are activated, AD can develop and produce senile plaques and neurofibrillary tangles throughout brain tissue. In this review, we propose a mechanism for neuronal cell cycle reentry and the development of AD. PMID:21630160

  19. Transcription patterns of genes encoding four metallothionein homologs in Daphnia pulex exposed to copper and cadmium are time- and homolog-dependent

    International Nuclear Information System (INIS)

    Asselman, Jana; Shaw, Joseph R.; Glaholt, Stephen P.; Colbourne, John K.; De Schamphelaere, Karel A.C.

    2013-01-01

    Highlights: •Transcription patterns of 4 metallothionein isoforms in Daphnia pulex. •Under cadmium and copper stress these patterns are time-dependent. •Under cadmium and copper stress these patterns are homolog-dependent. •The results stress the complex regulation of metallothioneins. -- Abstract: Metallothioneins are proteins that play an essential role in metal homeostasis and detoxification in nearly all organisms studied to date. Yet discrepancies between outcomes of chronic and acute exposure experiments hamper the understanding of the regulatory mechanisms of their isoforms following metal exposure. Here, we investigated transcriptional differences among four identified homologs (mt1–mt4) in Daphnia pulex exposed across time to copper and cadmium relative to a control. Transcriptional upregulation of mt1 and mt3 was detected on day four following exposure to cadmium, whereas that of mt2 and mt4 was detected on day two and day eight following exposure to copper. These results confirm temporal and metal-specific differences in the transcriptional induction of genes encoding metallothionein homologs upon metal exposure which should be considered in ecotoxicological monitoring programs of metal-contaminated water bodies. Indeed, the mRNA expression patterns observed here illustrate the complex regulatory system associated with metallothioneins, as these patterns are not only dependent on the metal, but also on exposure time and the homolog studied. Further phylogenetic analysis and analysis of regulatory elements in upstream promoter regions revealed a high degree of similarity between metallothionein genes of Daphnia pulex and Daphnia magna, a species belonging to the same genus. These findings, combined with a limited amount of available expression data for D. magna metallothionein genes, tentatively suggest a potential generalization of the metallothionein response system between these Daphnia species

  20. Transcription patterns of genes encoding four metallothionein homologs in Daphnia pulex exposed to copper and cadmium are time- and homolog-dependent

    Energy Technology Data Exchange (ETDEWEB)

    Asselman, Jana, E-mail: jana.asselman@ugent.be [Laboratory of Environmental Toxicology and Aquatic Ecology, Ghent University, Ghent (Belgium); Shaw, Joseph R.; Glaholt, Stephen P. [The School of Public and Environmental Affairs, Indiana University, Bloomington, IN (United States); Colbourne, John K. [School of Biosciences, The University of Birmingham, Birmingham (United Kingdom); De Schamphelaere, Karel A.C. [Laboratory of Environmental Toxicology and Aquatic Ecology, Ghent University, Ghent (Belgium)

    2013-10-15

    Highlights: •Transcription patterns of 4 metallothionein isoforms in Daphnia pulex. •Under cadmium and copper stress these patterns are time-dependent. •Under cadmium and copper stress these patterns are homolog-dependent. •The results stress the complex regulation of metallothioneins. -- Abstract: Metallothioneins are proteins that play an essential role in metal homeostasis and detoxification in nearly all organisms studied to date. Yet discrepancies between outcomes of chronic and acute exposure experiments hamper the understanding of the regulatory mechanisms of their isoforms following metal exposure. Here, we investigated transcriptional differences among four identified homologs (mt1–mt4) in Daphnia pulex exposed across time to copper and cadmium relative to a control. Transcriptional upregulation of mt1 and mt3 was detected on day four following exposure to cadmium, whereas that of mt2 and mt4 was detected on day two and day eight following exposure to copper. These results confirm temporal and metal-specific differences in the transcriptional induction of genes encoding metallothionein homologs upon metal exposure which should be considered in ecotoxicological monitoring programs of metal-contaminated water bodies. Indeed, the mRNA expression patterns observed here illustrate the complex regulatory system associated with metallothioneins, as these patterns are not only dependent on the metal, but also on exposure time and the homolog studied. Further phylogenetic analysis and analysis of regulatory elements in upstream promoter regions revealed a high degree of similarity between metallothionein genes of Daphnia pulex and Daphnia magna, a species belonging to the same genus. These findings, combined with a limited amount of available expression data for D. magna metallothionein genes, tentatively suggest a potential generalization of the metallothionein response system between these Daphnia species.

  1. Single-cell RNA sequencing reveals metallothionein heterogeneity during hESC differentiation to definitive endoderm

    Directory of Open Access Journals (Sweden)

    Junjie Lu

    2018-04-01

    Full Text Available Differentiation of human pluripotent stem cells towards definitive endoderm (DE is the critical first step for generating cells comprising organs such as the gut, liver, pancreas and lung. This in-vitro differentiation process generates a heterogeneous population with a proportion of cells failing to differentiate properly and maintaining expression of pluripotency factors such as Oct4. RNA sequencing of single cells collected at four time points during a 4-day DE differentiation identified high expression of metallothionein genes in the residual Oct4-positive cells that failed to differentiate to DE. Using X-ray fluorescence microscopy and multi-isotope mass spectrometry, we discovered that high intracellular zinc level corresponds with persistent Oct4 expression and failure to differentiate. This study improves our understanding of the cellular heterogeneity during in-vitro directed differentiation and provides a valuable resource to improve DE differentiation efficiency. Keywords: hPSC, Differentiation, Definitive endoderm, Heterogeneity, Single cell, RNA sequencing

  2. The renal metallothionein expression profile is altered in human lupus nephritis

    DEFF Research Database (Denmark)

    Faurschou, Mikkel; Penkowa, Milena; Andersen, Claus Bøgelund

    2008-01-01

    of standard statistical methods. RESULTS: Proximal tubules displaying epithelial cell MT-I+II depletion in combination with luminal MT-I+II expression were observed in 31 out of 37 of the lupus nephritis specimens, but not in any of the control sections (P = 0.006). The tubular MT score, defined as the median......INTRODUCTION: Metallothionein (MT) isoforms I + II are polypeptides with potent antioxidative and anti-inflammatory properties. In healthy kidneys, MT-I+II have been described as intracellular proteins of proximal tubular cells. The aim of the present study was to investigate whether the renal MT......-I+II expression profile is altered during lupus nephritis. METHODS: Immunohistochemistry was performed on renal biopsies from 37 patients with lupus nephritis. Four specimens of healthy renal tissue served as controls. Clinicopathological correlation studies and renal survival analyses were performed by means...

  3. Metallothionein 1+2 protect the CNS during neuroglial degeneration induced by 6-aminonicotinamide

    DEFF Research Database (Denmark)

    Penkowa, Milena; Giralt, Mercedes; Camats, Jordi

    2002-01-01

    6-Aminonicotinamide (6-AN) is a niacin antagonist, which leads to degeneration of gray matter astrocytes. Metallothionein 1+2 (MT-1+2) are neuroprotective factors in the central nervous system (CNS), and to determine the roles for MT after 6-AN, we have examined transgenic mice overexpressing MT-1...... (NITT), and the number of terminal deoxynucleotidyl transferase [TdT]-mediated deoxyuridine triphosphate [dUTP]-digoxigenin nick end labeling-positive (TUNEL+), caspase-3+ apoptotic cells were significantly increased in the brainstem of normal mice after 6-AN. In the TgMTI* mice, the 6-AN-induced tissue...... damage was decreased in comparison to control mice, and they showed significantly reduced numbers of recruited macrophages and T lymphocytes, and a drastic reduction of oxidative stress and apoptotic cell death. In addition, the accompanying reactive astrogliosis was increased in the transgenic mice...

  4. Effect of gamma irradiation, culture conditions and media composition on metallothionein production by Bacillus pantothenticus

    International Nuclear Information System (INIS)

    Tawfik, Z.S.; Swailam, H.M.; EL-Sonbaty, S.M.; Sayed, M.A.

    2010-01-01

    Metallothioneins (MTs) are cystine rich proteins found in all living organisms and play important roles as a radical scavenger and in metal homeostasis. Their optimum culture conditions and media composition of B. pantothenticuszn and B.pantothenticuscu were 1.5 g/L maltose and 1.5 g/l lactose as media carbon sources respectively, 48 hrs incubation period, 35 degree C, ph 8, 200 r.p.m. agitation speed, 26 g/L ammonium dihydrogen orthophosphate as nitrogen source, 0.5 g/L cysteine, 6% of 2.5x107 c.f.u./ml. inoculum size and exposure to a level dose of 4 kGy of gamma radiation. All the previous parameters increased the production of MT by B. pantothenticuszn and B.pantothenticuscu strains 12 and 10 times, respectively compared to the parent strains

  5. Increased demyelination and axonal damage in metallothionein I+II-deficient mice during experimental autoimmune encephalomyelitis

    DEFF Research Database (Denmark)

    Penkowa, M; Espejo, C; Martínez-Cáceres, E M

    2003-01-01

    Metallothioneins I+II (MT-I+II) are antioxidant, neuroprotective factors. We previously showed that MT-I+II deficiency during experimental autoimmune encephalomyelitis (EAE) leads to increased disease incidence and clinical symptoms. Moreover, the inflammatory response of macrophages and T cells......, oxidative stress, and apoptotic cell death during EAE were increased by MT-I+II deficiency. We now show for the first time that demyelination and axonal damage are significantly increased in MT-I+II deficient mice during EAE. Furthermore, oligodendroglial regeneration, growth cone formation, and tissue...... repair including expression of trophic factors were significantly reduced in MT-I+II-deficient mice during EAE. Accordingly, MT-I+II have protective and regenerative roles in the brain....

  6. Reaper-Induced Apoptosis

    National Research Council Canada - National Science Library

    Perry, Jennifer

    2005-01-01

    Reaper is a central regulator of apoptosis in the fly, Drosophila melanogaster. At the start of this proposal our laboratory identified what was believed to be a pro-apoptotic human homolog of Reaper...

  7. Apoptosis in Pneumovirus Infection

    Directory of Open Access Journals (Sweden)

    Reinout A. Bem

    2013-01-01

    Full Text Available Pneumovirus infections cause a wide spectrum of respiratory disease in humans and animals. The airway epithelium is the major site of pneumovirus replication. Apoptosis or regulated cell death, may contribute to the host anti-viral response by limiting viral replication. However, apoptosis of lung epithelial cells may also exacerbate lung injury, depending on the extent, the timing and specific location in the lungs. Differential apoptotic responses of epithelial cells versus innate immune cells (e.g., neutrophils, macrophages during pneumovirus infection can further contribute to the complex and delicate balance between host defense and disease pathogenesis. The purpose of this manuscript is to give an overview of the role of apoptosis in pneumovirus infection. We will examine clinical and experimental data concerning the various pro-apoptotic stimuli and the roles of apoptotic epithelial and innate immune cells during pneumovirus disease. Finally, we will discuss potential therapeutic interventions targeting apoptosis in the lungs.

  8. Metallothionein in brook trout (Salvenlinus fontinalis) as a biological indicator of cadmium stress

    International Nuclear Information System (INIS)

    Hamilton, S.J.; Mehrle, P.M.

    1987-01-01

    A cadmium-saturation technique for quantifying metallothionein in mammalian tissues was evaluated for use in fish tissue. Metallothionein characteristically binds 7 gram-atoms of a metal such as cadmium per mole of protein so saturating MT with respect to one metal and then quantifying that metal would thus result in the indirect quantification of MT. The authors administered 3 mg 109 cadmium/kg body weight by intraperitoneal injection over a 5-day period to adult brook trout Salvelinus fontinalis to induce MT in liver and kidney tissues. Homogenates were centrifuged and the supernatant was used to quantitate cadmium in three fractions: 100,000 g supernatant, cadmium-saturated MT, and unsaturated MT. The cadmium-saturated MT method involved the following steps: saturation of MT in an aliquot of 100,000 g supernatant with excess cadmium; removal of excess cadmium by addition of 2% hemoglobin; denaturation of hemoglobin by heating at 100 0 C followed by rapid cooling on ice; centrifugation at 10,000 g; digestion of an aliquot of supernatant in concentrated nitric acid for 16 hours at 70 0 C, and quantification of cadmium by atomic absorption and graphite furnace techniques or radiometric measurement with a scintillation counter. The cadmium saturation technique was modified in two ways so the amount of cadmium bound to unsaturated MT could be measured; first, the binding sites on MT were not saturated with excess cadmium, and second, the concentration of hemoglobin added to remove free cadmium and aid in coagulating low-molecular-weight proteins was 1% instead of 2%. The method gave precise measurements of MT concentrations when aliquots of liver homogenate which were analyzed separately were quantified by atomic absorption or radiometric measurements. Two to four times more cadmium and MT concentrated in the liver of treated fish than in the kidney

  9. A Determination of Metallothionein in Larvae of Freshwater Midges (Chironomus riparius Using Brdicka Reaction

    Directory of Open Access Journals (Sweden)

    Rene Kizek

    2008-07-01

    Full Text Available Among wide spectrum of biomolecules induced by various stress factors low molecular mass protein called metallothionein (MT is suitable for assessment of the heavy metal environmental pollution. The aim of this work was to determine the metallothionein and total thiols content in larvae of freshwater midges (Chironomus riparius sampled from laboratory exposure to cadmium(II ions and from field studies using differential pulse voltammetry Brdicka reaction. Unique electrochemical instrument, stationary electrochemical analyser Autolab coupled with autosampler, was utilized for the analysis of the samples. The detection limit for MT was evaluated as 5 nM. The larvae exposed to two doses (50 ng/g or 50 μg/g of cadmium(II ions for fifteen days under laboratory controlled conditions were at the end of the exposure killed, homogenized and analysed. MT content in control samples was 1.2 μM, in larvae exposed to 50 ng Cd/g it was 2.0 μM and in larvae exposed to 50 μg Cd/g 2.9 μM. Moreover at field study chironomid larvae as well as sediment samples have been collected from eight field sites with different levels of pollution by heavy. The metals content (chromium, nickel, copper, zinc, arsenic, molybdenum, cadmium, tin and lead in the sediment and or MT content in the chironomid larvae were determined by inductively coupled plasma mass spectrometry or Brdicka reaction, respectively.

  10. Metallothionein as a compensatory component prevents intermittent hypoxia-induced cardiomyopathy in mice

    International Nuclear Information System (INIS)

    Yin, Xia; Zhou, Shanshan; Zheng, Yang; Tan, Yi; Kong, Maiying; Wang, Bo; Feng, Wenke; Epstein, Paul N.; Cai, Jun; Cai, Lu

    2014-01-01

    Obstructive sleep apnea (OSA) causes chronic intermittent hypoxia (IH) to induce cardiovascular disease, which may be related to oxidative damage. Metallothionein (MT) has been extensively proved to be an endogenous and highly inducible antioxidant protein expressed in the heart. Therefore, we tested the hypotheses that oxidative stress plays a critical role in OSA induced cardiac damage and MT protects the heart from OSA-induced cardiomyopathy. To mimic hypoxia/reoxygenation events that occur in adult OSA patients, mice were exposed to IH for 3 days to 8 weeks. The IH paradigm consisted of alternating cycles of 20.9% O 2 /8% O 2 F I O 2 (30 episodes per hour) with 20 s at the nadir F I O 2 for 12 h a day during daylight. IH significantly increased the ratio of heart weight to tibia length at 4 weeks with a decrease in cardiac function from 4 to 8 weeks. Cardiac oxidative damage and fibrosis were observed after 4 and 8 weeks of IH exposures. Endogenous MT expression was up-regulated in response to 3-day IH, but significantly decreased at 4 and 8 weeks of IH. In support of MT as a major compensatory component, mice with cardiac overexpression of MT gene and mice with global MT gene deletion were completely resistant, and highly sensitive, respectively, to chronic IH induced cardiac effects. These findings suggest that chronic IH induces cardiomyopathy characterized by oxidative stress-mediated cardiac damage and the antioxidant MT protects the heart from such pathological and functional changes. - Highlights: • The effect of intermittent hypoxia (IH) on cardiac metallothionein (MT) • Cardiac MT expression was up-regulated in response to 3-day IH. • Exposure to 4- or 8-week IH downregulated cardiac MT expression. • Overexpression of cardiac MT protects from IH-induced cardiac damage. • Global deletion of MT gene made the heart more sensitive to IH damage

  11. Induction of Cellular Metallothionein in Irradiated Rats Supplemented with Egyptian Propolis Extract

    International Nuclear Information System (INIS)

    Nada, A.SH.; Azab, KH.SH.

    2005-01-01

    Proplis, a resinous yellow to dark substance collected by worker honeybees has been extensively used in folk medicine for management of a wide spectrum of disorders. The current study was conducted to evaluate the role of Egyptian propolis extract in modification of metallothionen (MT) induction in rats exposed to whole body fractionated gamma irradiation (delivered as 1.5 Gy every day up to 7.5 Gy total dose) and the relevance of certain metals (Cu, Zn, Mg, Mn and Fe) for metallothionein induction. In addition, lipid peroxides (thiobarbituric acid reactive substance; TEARS) and reduced glutathione (GSH) concentrations were observed in different subjected tissues. Metal content of crude propolis and certain related natural forms (bee pollen and honey) were also identified. Propolis extract was supplemented daily to rats (10 ml/kg body wt/day) by stomach tube, 15 days before and during exposure to gamma radiation. Experimental investigations were carried out on the 1st and 10th days after the last irradiation fraction in liver, kidney, brain, heart, lung and spleen tissues. The results obtained reveal that the administration of propolis extract increased significantly the metallothionein (MT) concentration in all examined tissues as compared with control rats. Records on all subjected tissues imparted that propolis extract supplementation has significantly minimized the radiation-induced increases in the amount of TBARS, maintained GSH con centration within normal levels except for lung and spleen and increased MT levels comparing to irradiated rats. Furthermore, significant amelioration in the levels of trace metals was observed such as zinc and copper in liver, kidney and brain. It could be postulated that the prolonged administration of Egyptian propolis extract attenuates the lipid peroxidation process in different rat's tissues and that might attributed to its antioxidant potency partially expressed through MT induction, maintenance of GSH levels and the

  12. Review Paper: Polyphenolic Antioxidants and Neuronal Regeneration

    Directory of Open Access Journals (Sweden)

    Amin Ataie

    2016-05-01

    Full Text Available Many studies indicate that oxidative stress is involved in the pathophysiology of neurodegenerative diseases. Oxidative stress can induce neuronal damages, modulate intracellular signaling and ultimately leads to neuronal death by apoptosis or necrosis. To review antioxidants preventive effects on oxidative stress and neurodegenerative diseases we accumulated data from international medical journals and academic informations' sites. According to many studies, antioxidants could reduce toxic neuronal damages and many studies confirmed the efficacy of polyphenol antioxidants in fruits and vegetables to reduce neuronal death and to diminish oxidative stress. This systematic review showed the antioxidant activities of phytochemicals which play as natural neuroprotectives with low adverse effects against some neurodegenerative diseases as Parkinson or Alzheimer diseases.

  13. Review Paper: Polyphenolic Antioxidants and Neuronal Regeneration

    Directory of Open Access Journals (Sweden)

    Amin Ataie

    2016-04-01

    Full Text Available Many studies indicate that oxidative stress is involved in the pathophysiology of neurodegenerative diseases. Oxidative stress can induce neuronal damages, modulate intracellular signaling and ultimately leads to neuronal death by apoptosis or necrosis. To review antioxidants preventive effects on oxidative stress and neurodegenerative diseases we accumulated data from international medical journals and academic informations' sites. According to many studies, antioxidants could reduce toxic neuronal damages and many studies confirmed the efficacy of polyphenol antioxidants in fruits and vegetables to reduce neuronal death and to diminish oxidative stress. This systematic review showed the antioxidant activities of phytochemicals which play as natural neuroprotectives with low adverse effects against some neurodegenerative diseases as Parkinson or Alzheimer diseases.

  14. Labeling of neuronal differentiation and neuron cells with biocompatible fluorescent nanodiamonds.

    Science.gov (United States)

    Hsu, Tzu-Chia; Liu, Kuang-Kai; Chang, Huan-Cheng; Hwang, Eric; Chao, Jui-I

    2014-05-16

    Nanodiamond is a promising carbon nanomaterial developed for biomedical applications. Here, we show fluorescent nanodiamond (FND) with the biocompatible properties that can be used for the labeling and tracking of neuronal differentiation and neuron cells derived from embryonal carcinoma stem (ECS) cells. The fluorescence intensities of FNDs were increased by treatment with FNDs in both the mouse P19 and human NT2/D1 ECS cells. FNDs were taken into ECS cells; however, FNDs did not alter the cellular morphology and growth ability. Moreover, FNDs did not change the protein expression of stem cell marker SSEA-1 of ECS cells. The neuronal differentiation of ECS cells could be induced by retinoic acid (RA). Interestingly, FNDs did not affect on the morphological alteration, cytotoxicity and apoptosis during the neuronal differentiation. Besides, FNDs did not alter the cell viability and the expression of neuron-specific marker β-III-tubulin in these differentiated neuron cells. The existence of FNDs in the neuron cells can be identified by confocal microscopy and flow cytometry. Together, FND is a biocompatible and readily detectable nanomaterial for the labeling and tracking of neuronal differentiation process and neuron cells from stem cells.

  15. Neurons other than motor neurons in motor neuron disease.

    Science.gov (United States)

    Ruffoli, Riccardo; Biagioni, Francesca; Busceti, Carla L; Gaglione, Anderson; Ryskalin, Larisa; Gambardella, Stefano; Frati, Alessandro; Fornai, Francesco

    2017-11-01

    Amyotrophic lateral sclerosis (ALS) is typically defined by a loss of motor neurons in the central nervous system. Accordingly, morphological analysis for decades considered motor neurons (in the cortex, brainstem and spinal cord) as the neuronal population selectively involved in ALS. Similarly, this was considered the pathological marker to score disease severity ex vivo both in patients and experimental models. However, the concept of non-autonomous motor neuron death was used recently to indicate the need for additional cell types to produce motor neuron death in ALS. This means that motor neuron loss occurs only when they are connected with other cell types. This concept originally emphasized the need for resident glia as well as non-resident inflammatory cells. Nowadays, the additional role of neurons other than motor neurons emerged in the scenario to induce non-autonomous motor neuron death. In fact, in ALS neurons diverse from motor neurons are involved. These cells play multiple roles in ALS: (i) they participate in the chain of events to produce motor neuron loss; (ii) they may even degenerate more than and before motor neurons. In the present manuscript evidence about multi-neuronal involvement in ALS patients and experimental models is discussed. Specific sub-classes of neurons in the whole spinal cord are reported either to degenerate or to trigger neuronal degeneration, thus portraying ALS as a whole spinal cord disorder rather than a disease affecting motor neurons solely. This is associated with a novel concept in motor neuron disease which recruits abnormal mechanisms of cell to cell communication.

  16. Corvitin restores metallothionein and glial fibrillary acidic protein levels in rat brain affected by pituitrin-izadrin

    OpenAIRE

    H. N. Shiyntum; O. O. Dovban; Y. P. Kovalchuk; T. Ya. Yaroshenko2; G. A. Ushakova1

    2017-01-01

    In this research, we investigated the effect of pituitrin-izadrin induced injury on the levels of metallothionein (MT) and soluble and filament forms of glial fibrillary acidic protein (GFAP) in the hippocampus, cerebellum, thalamus, and the cerebral cortex, and examined the effect of corvitin on the brain under the noted changes. Our results showed oppositely directed changes – a decrease in the level of MT and an increase in GFAP in the rat brain, with a tendency to astrogliosis development...

  17. Utilizing od adsorptive transfer stripping technique Brdicka reaction for determination of metallothioneins level in melanoma cells, blood serum and tissues

    Czech Academy of Sciences Publication Activity Database

    Křížková, S.; Fabrik, I.; Adam, V.; Kukačka, J.; Průša, R.; Chavis, G. J.; Trnková, L.; Strnádel, Ján; Horák, Vratislav; Kizek, R.

    2008-01-01

    Roč. 8, - (2008), s. 3106-3122 ISSN 1424-8220 R&D Projects: GA AV ČR IAA600450601; GA ČR(CZ) GA524/04/0102 Grant - others:GA AV ČR(CZ) IAA401990701 Institutional research plan: CEZ:AV0Z50450515 Keywords : metallothionein * protein * tumour marker Subject RIV: FD - Oncology ; Hematology Impact factor: 1.870, year: 2008

  18. Investigation of the Antioxidant Properties of Metallothionein in Transgenic Tobacco Plants using Voltammetry at a Carbon Paste Electrode

    Czech Academy of Sciences Publication Activity Database

    Shetivska, V.; Adam, V.; Prášek, J.; Macek, Tomáš; Macková, M.; Havel, L.; Dioplan, V.; Zehnálek, J.; Hubálek, J.; Kižek, R.

    2011-01-01

    Roč. 6, č. 7 (2011), s. 2869-2883 ISSN 1452-3981 Grant - others:GA ČR(CZ) GA522/07/0692; GA ČR(CZ) GA102/08/1546 Institutional research plan: CEZ:AV0Z40550506 Keywords : square wave voltammetry * carbon paste electrode * DNA * metallothionein Subject RIV: CG - Electrochemistry Impact factor: 3.729, year: 2011

  19. Short-term exposure of mice to gasoline vapor increases the metallothionein expression in the brain, lungs and kidney

    OpenAIRE

    Grebic, Damir; Jakovac, Hrvoje; Mrakovcic-Sutic, Ines; Tomac, J.; Bulog, A.; Micovic, V.; Radosevic-Stasic, Biserka

    2007-01-01

    Environmental airborne pollution has been repeatedly shown to affect multiple aspects of brain and cardiopulmonary function, leading to cognitive and behavioral changes and to the pronounced inflammatory response in the respiratory airways. Since in the cellular defense system the important role might have stress proteins-metallothionein (MT)-I and MT-II, which are involved in sequestration and dispersal of metal ions, regulation of the biosynthesis and activities of z...

  20. Effects of Copper on Hemocyte Apoptosis, ROS Production, and Gene Expression in White Shrimp Litopenaeus vannamei.

    Science.gov (United States)

    Guo, Hui; Li, Kexu; Wang, Wei; Wang, Chenggui; Shen, Yuchun

    2017-10-01

    Copper, a common chemical contaminant in aquatic environment, is known to be toxic to aquatic life at high concentrations. In the present study, we evaluated the apoptotic cell ratio and ROS production in hemocytes of the white shrimp Litopenaeus vannamei exposed to 1 or 5 mg L -1 Cu for 0, 3, 6, 12, 24, and 48 h. The expression changes of antioxidant biomarker genes, i.e., copper-zinc superoxide dismutase (Cu-Zn SOD) and catalase (CAT), apoptosis-related genes, i.e., caspase-3 and inhibitor of apoptosis protein (IAP), and a specific biomarker gene of heavy metal pollution, i.e., metallothionein (MT), were also determined in hemocytes. Significant increases in ROS production were observed in both treatment groups at each time points. The apoptotic cell ratios were significantly increased at 6-48 h among shrimp exposed to 1 mg L -1 Cu and at each time points in 5 mg L -1 Cu group. These results indicated that Cu would induce oxidative stress and apoptosis in the hemocyte of L. vannamei. Quantitative real-time PCR analysis revealed that the relative expression levels of Cu-Zn SOD, CAT, caspase-3, IAP, and MT were upregulated in a dose-dependent and time-dependent manner, suggesting the involvement of these genes in stress response against Cu exposure.

  1. Apoptosis signaling and radiation protection

    International Nuclear Information System (INIS)

    Morita, Akinori; Suzuki, Norio; Hosoi, Yoshio

    2005-01-01

    Radiation protection by apoptosis control is the suppression of cell death in highly radiosensitive tissues. This paper describes the outline of radiation-induced apoptosis framework, apoptosis-concerned target molecules possibly related to apoptosis by radiation and their inhibitors. Although there are intrinsic (via mitochondria) and extrinsic (via death receptor) pathways in apoptosis, this review mainly mentions the former which is more important in radiation-induced apoptosis. Those molecules known at present in the apoptosis are caspase, Bcl-2 family and p53. Caspase, a group of cystein proteases, initiates apoptosis but its inhibition is known not always to result in apoptosis suppression, suggesting the existence of caspase-independent pathways. Bcl-2 family involves apoptosis-suppressing (possessing BH domains) and -promoting (lacking BH domains or possessing BH3 domain alone/BH3-only protein) groups. Two p53-transcription-dependent and one -independent pathways in p53-induced apoptosis are known and p53 can be a most possible target molecule since it positions at the start of apoptosis. Authors have found a vanadate inactivates p53. Inhibitors affecting upstream molecules of apoptosis will be the most useful candidate for apoptosis suppression/radiation protection. (S.I.) 106 refs

  2. Molecular control of copper homeostasis in filamentous fungi: increased expression of a metallothionein gene during aging of Podospora anserina.

    Science.gov (United States)

    Averbeck, N B; Borghouts, C; Hamann, A; Specke, V; Osiewacz, H D

    2001-01-01

    The lifespan of the ascomycete Podospora anserina was previously demonstrated to be significantly increased in a copper-uptake mutant, suggesting that copper is a potential stressor involved in degenerative processes. In order to determine whether changes in copper stress occur in the cells during normal aging of cultures, we cloned and characterized a gene coding for a component of the molecular machinery involved in the control of copper homeostasis. This gene, PaMt1, is a single-copy gene that encodes a metallothionein of 26 amino acids. The coding sequence of PaMt1 is interrupted by a single intron. The deduced amino acid sequence shows a high degree of sequence identity to metallothioneins of the filamentous ascomycete Neurospora crassa and the basidiomycete Agaricus bisporus, and to the N-terminal portion of mammalian metallothioneins. Levels of PaMt1 transcript increase in response to elevated amounts of copper in the growth medium and during aging of wild-type cultures. In contrast, in the long-lived mutant grisea, transcript levels first increase but then decrease again. The ability of wild-type cultures to respond to exogenous copper stress via the induction of PaMt1 transcription is not affected as they grow older.

  3. Roles for the pro-neurotrophin receptor sortilin in neuronal development, aging and brain injury

    DEFF Research Database (Denmark)

    Jansen, Pernille; Giehl, Klaus; Nyengaard, Jens R

    2007-01-01

    Neurotrophins are essential for development and maintenance of the vertebrate nervous system. Paradoxically, although mature neurotrophins promote neuronal survival by binding to tropomyosin receptor kinases and p75 neurotrophin receptor (p75(NTR)), pro-neurotrophins induce apoptosis in cultured......)/sortilin receptor complex to neuronal viability. In the developing retina, Sortilin 1 (Sort1)(-/-) mice showed reduced neuronal apoptosis that was indistinguishable from that observed in p75(NTR)-deficient (Ngfr(-/-)) mice. To our surprise, although sortilin deficiency did not affect developmentally regulated...... apoptosis of sympathetic neurons, it did prevent their age-dependent degeneration. Furthermore, in an injury protocol, lesioned corticospinal neurons in Sort1(-/-) mice were protected from death. Thus, the sortilin pathway has distinct roles in pro-neurotrophin-induced apoptotic signaling in pathological...

  4. p,p'-DDT induces testicular oxidative stress-induced apoptosis in adult rats.

    Science.gov (United States)

    Marouani, Neila; Hallegue, Dorsaf; Sakly, Mohsen; Benkhalifa, Moncef; Ben Rhouma, Khémais; Tebourbi, Olfa

    2017-05-26

    The 1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane (p,p'-DDT) is a known persistent organic pollutant and male reproductive toxicant. The present study is designed to test the hypothesis that oxidative stress mediates p,p'-DDT-induced apoptosis in testis. Male Wistar rats received an intraperitoneal (ip) injection of the pesticide at doses of 50 and 100mg/kg for 10 consecutive days. The oxidative stress was evaluated by biomarkers such lipid peroxidation (LPO) and metallothioneins (MTs) levels. Antioxidant enzymes activities was assessed by determination of superoxide dismutase (SOD), catalase (CAT) and hydrogen peroxide (H 2 O 2 ) production. In addition, glutathione-dependent enzymes and reducing power in testis was evaluated by glutathione peroxidase (Gpx), glutathione reductase (GR), glutathione S-transferase (GST) activities and reduced and oxidized glutathione (GSH - GSSG) levels. Apoptosis was evaluated by DNA fragmentation detected by agarose gel electrophoresis. Germinal cells apoptosis and the apoptotic index was assessed through the TUNEL assay. After 10 days of treatment, an increase in LPO level and H 2 O 2 production occurred, while MTs level, SOD and CAT activities were decreased. Also, the Gpx, GR, GST, and GSH activities were decreased, whereas GSSG activity was increased. Testicular tissues of treated rats showed pronounced degradation of the DNA into oligonucleotides as seen in the typical electrophoretic DNA ladder pattern. Intense apoptosis was observed in germinal cells of DDT-exposed rats. In addition, the apoptotic index was significantly increased in testis of DDT-treated rats. These results clearly suggest that DDT sub-acute treatment causes oxidative stress in rat testis leading to apoptosis.

  5. Metallothionein as a compensatory component prevents intermittent hypoxia-induced cardiomyopathy in mice

    Energy Technology Data Exchange (ETDEWEB)

    Yin, Xia; Zhou, Shanshan [The First Hospital of Jilin University, Changchun, 130021 (China); KCHRI at the Department of Pediatrics, School of Medicine, University of Louisville, Louisville, 40202 (United States); Zheng, Yang, E-mail: zhengyang@jlu.edu.cn [The First Hospital of Jilin University, Changchun, 130021 (China); Tan, Yi [KCHRI at the Department of Pediatrics, School of Medicine, University of Louisville, Louisville, 40202 (United States); Chinese–American Research Institute for Diabetic Complications, Wenzhou Medical College School of Pharmacy, Wenzhou, 325035 (China); Kong, Maiying [Department of Bioinformatics and Biostatistics, School of Public Health and Information Sciences, University of Louisville, Louisville, KY 40202 (United States); Wang, Bo [KCHRI at the Department of Pediatrics, School of Medicine, University of Louisville, Louisville, 40202 (United States); Department of Pathology, Inner Mongolia Forestry General Hospital, Yakeshi, 022150 (China); Feng, Wenke [Department of Medicine, School of Medicine, University of Louisville, Louisville, 40202 (United States); Epstein, Paul N. [KCHRI at the Department of Pediatrics, School of Medicine, University of Louisville, Louisville, 40202 (United States); Cai, Jun, E-mail: j0cai002@louisville.edu [KCHRI at the Department of Pediatrics, School of Medicine, University of Louisville, Louisville, 40202 (United States); Cai, Lu [KCHRI at the Department of Pediatrics, School of Medicine, University of Louisville, Louisville, 40202 (United States); Chinese–American Research Institute for Diabetic Complications, Wenzhou Medical College School of Pharmacy, Wenzhou, 325035 (China); Department of Medicine, School of Medicine, University of Louisville, Louisville, 40202 (United States)

    2014-05-15

    Obstructive sleep apnea (OSA) causes chronic intermittent hypoxia (IH) to induce cardiovascular disease, which may be related to oxidative damage. Metallothionein (MT) has been extensively proved to be an endogenous and highly inducible antioxidant protein expressed in the heart. Therefore, we tested the hypotheses that oxidative stress plays a critical role in OSA induced cardiac damage and MT protects the heart from OSA-induced cardiomyopathy. To mimic hypoxia/reoxygenation events that occur in adult OSA patients, mice were exposed to IH for 3 days to 8 weeks. The IH paradigm consisted of alternating cycles of 20.9% O{sub 2}/8% O{sub 2} F{sub I}O{sub 2} (30 episodes per hour) with 20 s at the nadir F{sub I}O{sub 2} for 12 h a day during daylight. IH significantly increased the ratio of heart weight to tibia length at 4 weeks with a decrease in cardiac function from 4 to 8 weeks. Cardiac oxidative damage and fibrosis were observed after 4 and 8 weeks of IH exposures. Endogenous MT expression was up-regulated in response to 3-day IH, but significantly decreased at 4 and 8 weeks of IH. In support of MT as a major compensatory component, mice with cardiac overexpression of MT gene and mice with global MT gene deletion were completely resistant, and highly sensitive, respectively, to chronic IH induced cardiac effects. These findings suggest that chronic IH induces cardiomyopathy characterized by oxidative stress-mediated cardiac damage and the antioxidant MT protects the heart from such pathological and functional changes. - Highlights: • The effect of intermittent hypoxia (IH) on cardiac metallothionein (MT) • Cardiac MT expression was up-regulated in response to 3-day IH. • Exposure to 4- or 8-week IH downregulated cardiac MT expression. • Overexpression of cardiac MT protects from IH-induced cardiac damage. • Global deletion of MT gene made the heart more sensitive to IH damage.

  6. Alpha-2 agonist attenuates ischemic injury in spinal cord neurons.

    Science.gov (United States)

    Freeman, Kirsten A; Puskas, Ferenc; Bell, Marshall T; Mares, Joshua M; Foley, Lisa S; Weyant, Michael J; Cleveland, Joseph C; Fullerton, David A; Meng, Xianzhong; Herson, Paco S; Reece, T Brett

    2015-05-01

    Paraplegia secondary to spinal cord ischemia-reperfusion injury remains a devastating complication of thoracoabdominal aortic intervention. The complex interactions between injured neurons and activated leukocytes have limited the understanding of neuron-specific injury. We hypothesize that spinal cord neuron cell cultures subjected to oxygen-glucose deprivation (OGD) would simulate ischemia-reperfusion injury, which could be attenuated by specific alpha-2a agonism in an Akt-dependent fashion. Spinal cords from perinatal mice were harvested, and neurons cultured in vitro for 7-10 d. Cells were pretreated with 1 μM dexmedetomidine (Dex) and subjected to OGD in an anoxic chamber. Viability was determined by MTT assay. Deoxyuridine-triphosphate nick-end labeling staining and lactate dehydrogenase (LDH) assay were used for apoptosis and necrosis identification, respectively. Western blot was used for protein analysis. Vehicle control cells were only 59% viable after 1 h of OGD. Pretreatment with Dex significantly preserves neuronal viability with 88% viable (P control cells by 50% (P neuron cell culture, OGD mimics neuronal metabolic derangement responsible for paraplegia after aortic surgery. Dex preserves neuronal viability and decreases apoptosis in an Akt-dependent fashion. Dex demonstrates clinical promise for reducing the risk of paraplegia after high-risk aortic surgery. Copyright © 2015 Elsevier Inc. All rights reserved.

  7. Alterations of tissue metallothionein and vitellogenin concentrations in tropical cup oysters (Saccostrea sp.) following short-term (96 h) exposure to cadmium

    International Nuclear Information System (INIS)

    Moncaleano-Niño, Angela M.; Barrios-Latorre, Sergio A.; Poloche-Hernández, Javier F.; Becquet, Vanessa; Huet, Valérie; Villamil, Luisa; Thomas-Guyon, Hélène; Ahrens, Michael J.; Luna-Acosta, Andrea

    2017-01-01

    Highlights: • The cup oyster Saccostrea sp. is present in Santa Marta, Colombian Caribbean. • 96 h exposure of oysters to Cd increased metallothionein concentrations in digestive glands up to 2-fold. • 96 h exposure of oysters to Cd decreased vitellogenin concentrations in gonads up to 6-fold. • Metallothionein and vitellogenin tissue concentrations correlated with whole tissue Cd concentrations. • Significant changes in metallothionein and vitellogenin levels were only evident at Cd concentrations above 100 μg/L. - Abstract: Metallothioneins and vitellogenins are low molecular weight proteins that have been used widely in environmental monitoring as biomarkers of exposure and damage to metals and estrogenic compounds, respectively. In the present study, the responses of metallothionein and vitellogenin tissue concentrations were measured following acute (96 h) aqueous exposures to cadmium in Saccostrea sp., a tropical cup oyster native to the Western Pacific Ocean that has recently established itself in the Caribbean Sea. Adult oysters (1.5–5.0 cm shell length) collected from the municipal marina of Santa Marta, Colombia (Caribbean Sea) and acclimated for 5 days in the laboratory, were exposed to Cd at five concentrations (0, 1, 10, 100 and 1000 μg/L) and their tissues (gills, digestive gland and adductor muscle) were analyzed in pools of 5 individuals (3 replicates per concentration). Metallothioneins in digestive glands of oysters exposed to Cd concentrations ≥ 100 μg/L showed a significant increase, from 8.0 to 14.8 μg MT/mg total protein, whereas metallothionein concentrations in gills increased to lesser extent, and no differences were observed in adductor muscle. Metallothionein concentrations in digestive gland and gills correlated directly with whole soft tissue Cd concentrations (ranging from 2 to 297 μg/g dw Cd). Vitellogenin in homogenates of oyster gonad tissue, after 96 h of exposure to 1000 μg/L Cd, were significantly lower (0

  8. Alterations of tissue metallothionein and vitellogenin concentrations in tropical cup oysters (Saccostrea sp.) following short-term (96 h) exposure to cadmium

    Energy Technology Data Exchange (ETDEWEB)

    Moncaleano-Niño, Angela M.; Barrios-Latorre, Sergio A.; Poloche-Hernández, Javier F. [Department of Biological Sciences, Universidad de Bogota Jorge Tadeo Lozano, Carrera 4 No. 22-61, Bogota (Colombia); Becquet, Vanessa; Huet, Valérie [Littoral Environnement et Sociétés (LIENSs) – UMR 7266, CNRS-Université de La Rochelle, Bâtiment ILE 2, rue Olympe de Gouges, 17 000 La Rochelle (France); Villamil, Luisa [Department of Biological Sciences, Universidad de Bogota Jorge Tadeo Lozano, Carrera 4 No. 22-61, Bogota (Colombia); Thomas-Guyon, Hélène [Littoral Environnement et Sociétés (LIENSs) – UMR 7266, CNRS-Université de La Rochelle, Bâtiment ILE 2, rue Olympe de Gouges, 17 000 La Rochelle (France); Ahrens, Michael J., E-mail: michael.ahrens@utadeo.edu.co [Department of Biological Sciences, Universidad de Bogota Jorge Tadeo Lozano, Carrera 4 No. 22-61, Bogota (Colombia); Luna-Acosta, Andrea [Department of Biological Sciences, Universidad de Bogota Jorge Tadeo Lozano, Carrera 4 No. 22-61, Bogota (Colombia)

    2017-04-15

    Highlights: • The cup oyster Saccostrea sp. is present in Santa Marta, Colombian Caribbean. • 96 h exposure of oysters to Cd increased metallothionein concentrations in digestive glands up to 2-fold. • 96 h exposure of oysters to Cd decreased vitellogenin concentrations in gonads up to 6-fold. • Metallothionein and vitellogenin tissue concentrations correlated with whole tissue Cd concentrations. • Significant changes in metallothionein and vitellogenin levels were only evident at Cd concentrations above 100 μg/L. - Abstract: Metallothioneins and vitellogenins are low molecular weight proteins that have been used widely in environmental monitoring as biomarkers of exposure and damage to metals and estrogenic compounds, respectively. In the present study, the responses of metallothionein and vitellogenin tissue concentrations were measured following acute (96 h) aqueous exposures to cadmium in Saccostrea sp., a tropical cup oyster native to the Western Pacific Ocean that has recently established itself in the Caribbean Sea. Adult oysters (1.5–5.0 cm shell length) collected from the municipal marina of Santa Marta, Colombia (Caribbean Sea) and acclimated for 5 days in the laboratory, were exposed to Cd at five concentrations (0, 1, 10, 100 and 1000 μg/L) and their tissues (gills, digestive gland and adductor muscle) were analyzed in pools of 5 individuals (3 replicates per concentration). Metallothioneins in digestive glands of oysters exposed to Cd concentrations ≥ 100 μg/L showed a significant increase, from 8.0 to 14.8 μg MT/mg total protein, whereas metallothionein concentrations in gills increased to lesser extent, and no differences were observed in adductor muscle. Metallothionein concentrations in digestive gland and gills correlated directly with whole soft tissue Cd concentrations (ranging from 2 to 297 μg/g dw Cd). Vitellogenin in homogenates of oyster gonad tissue, after 96 h of exposure to 1000 μg/L Cd, were significantly lower (0

  9. Modulation of Apoptosis Controls Inhibitory Interneuron Number in the Cortex

    Directory of Open Access Journals (Sweden)

    Myrto Denaxa

    2018-02-01

    Full Text Available Cortical networks are composed of excitatory projection neurons and inhibitory interneurons. Finding the right balance between the two is important for controlling overall cortical excitation and network dynamics. However, it is unclear how the correct number of cortical interneurons (CIs is established in the mammalian forebrain. CIs are generated in excess from basal forebrain progenitors, and their final numbers are adjusted via an intrinsically determined program of apoptosis that takes place during an early postnatal window. Here, we provide evidence that the extent of CI apoptosis during this critical period is plastic and cell-type specific and can be reduced in a cell-autonomous manner by acute increases in neuronal activity. We propose that the physiological state of the emerging neural network controls the activity levels of local CIs to modulate their numbers in a homeostatic manner.

  10. Evaluation of cadmium, lead and metallothionein contents in the tissues of mussels (Mytilus galloprovincialis) from the Campania coast (Italy): levels and seasonal trends.

    Science.gov (United States)

    Scudiero, Rosaria; Cretì, Patrizia; Trinchella, Francesca; Grazia Esposito, Maria

    2014-01-01

    The biological effect of seasonality on cadmium, lead and metallothionein contents was assessed in mussels Mytilus galloprovincialis from natural banks located along the coastline of the Gulf of Naples (Campania, Italy). Heavy metals and metallothionein concentrations were measured in digestive and reproductive glands. The results showed a clear correlation between metallothionein content and the reproductive gland status determined during the seasons; on the contrary, no correlation was found between metallothionein and metal contents. Data allow us to hypothesize that metallothionein functions go beyond metal detoxification, thus opening new scenarios for these proteins in invertebrates. The effect of seasons on metals concentration in mussel tissues showed similar seasonal patterns between the sites, regardless of their anthropogenic impacts. Cadmium content was not strictly related to seasonal periods, whereas lead content was significantly lower in summer. The results also indicate that the metal contents in mussels from the Gulf of Naples do not represent a risk to human health, even in the period of their maximum accumulation, and that the relaying of mussels before marketing could improve the animal stress conditions, but having a slight effect on metal excretion. Copyright © 2014 Académie des sciences. Published by Elsevier SAS. All rights reserved.

  11. Mitochondria in neutrophil apoptosis

    NARCIS (Netherlands)

    van Raam, B. J.; Verhoeven, A. J.; Kuijpers, T. W.

    2006-01-01

    Central in the regulation of the short life span of neutrophils are their mitochondria. These organelles hardly contribute to the energy status of neutrophils but play a vital role in the apoptotic process. Not only do the mitochondria contain cytotoxic proteins that are released during apoptosis

  12. Metal components analysis of metallothionein-III in the brain sections of metallothionein-I and metallothionein-II null mice exposed to mercury vapor with HPLC/ICP-MS

    Energy Technology Data Exchange (ETDEWEB)

    Kameo, Satomi; Nakai, Kunihiko; Kurokawa, Naoyuki; Satoh, Hiroshi [Tohoku University, Graduate School of Medicine, Aoba-ku, Sendai (Japan); Kanehisa, Tomokazu; Naganuma, Akira [Tohoku University, Graduate School of Pharmaceutical Sciences, Sendai (Japan)

    2005-04-01

    Mercury vapor is effectively absorbed via inhalation and easily passes through the blood-brain barrier; therefore, mercury poisoning with primarily central nervous system symptoms occurs. Metallothionein (MT) is a cysteine-rich metal-binding protein and plays a protective role in heavy-metal poisoning and it is associated with the metabolism of trace elements. Two MT isoforms, MT-I and MT-II, are expressed coordinately in all mammalian tissues, whereas MT-III is a brain-specific member of the MT family. MT-III binds zinc and copper physiologically and is seemed to have important neurophysiological and neuromodulatory functions. The MT functions and metal components of MTs in the brain after mercury vapor exposure are of much interest; however, until now they have not been fully examined. In this study, the influences of the lack of MT-I and MT-II on mercury accumulation in the brain and the changes of zinc and copper concentrations and metal components of MTs were examined after mercury vapor exposure by using MT-I, II null mice and 129/Sv (wild-type) mice as experimental animals. MT-I, II null mice and wild-type mice were exposed to mercury vapor or an air stream for 2 h and were killed 24 h later. The brain was dissected into the cerebral cortex, the cerebellum, and the hippocampus. The concentrations of mercury in each brain section were determined by cold vapor atomic absorption spectrometry. The concentrations of mercury, copper, and zinc in each brain section were determined by inductively coupled plasma mass spectrometry (ICP-MS). The mercury accumulated in brains after mercury vapor exposure for MT-I, II null mice and wild-type mice. The mercury levels of MT-I, II null mice in each brain section were significantly higher than those of wild-type mice after mercury vapor exposure. A significant change of zinc concentrations with the following mercury vapor exposure for MT-I, II null mice was observed only in the cerebellum analyzed by two-way analysis of

  13. Apoptosis and inflammation

    Directory of Open Access Journals (Sweden)

    C. Haanen

    1995-01-01

    Full Text Available During the last few decades it has been recognized that cell death is not the consequence of accidental injury, but is the expression of a cell suicide programme. Kerr et al. (1972 introduced the term apoptosis. This form of cell death is under the influence of hormones, growth factors and cytokines, which depending upon the receptors present on the target cells, may activate a genetically controlled cell elimination process. During apoptosis the cell membrane remains intact and the cell breaks into apoptotic bodies, which are phagocytosed. Apoptosis, in contrast to necrosis, is not harmful to the host and does not induce any inflammatory reaction. The principal event that leads to inflammatory disease is cell damage, induced by chemical/physical injury, anoxia or starvation. Cell damage means leakage of cell contents into the adjacent tissues, resulting in the capillary transmigration of granulocytes to the injured tissue. The accumulation of neutrophils and release of enzymes and oxygen radicals enhances the inflammatory reaction. Until now there has been little research into the factors controlling the accumulation and the tissue load of granulocytes and their histotoxic products in inflammatory processes. Neutrophil apoptosis may represent an important event in the control of intlamtnation. It has been assumed that granulocytes disintegrate to apoptotic bodies before their fragments are removed by local macrophages. Removal of neutrophils from the inflammatory site without release of granule contents is of paramount importance for cessation of inflammation. In conclusion, apoptotic cell death plays an important role in inflammatory processes and in the resolution of inflammatory reactions. The facts known at present should stimulate further research into the role of neutrophil, eosinophil and macrophage apoptosis in inflammatory diseases.

  14. 5,7-Dimethoxycoumarin inhibits neuronal apoptosis by targeting ...

    African Journals Online (AJOL)

    expression of caspase-3 in brain tissues and thus may be useful for cerebral ... dimethoxycoumarin also causes cell cycle arrest ..... Fan W, Dai Y, Xu H. Caspase-3 modulates regenerative response after stroke. Stem Cells 2014; 32: 473‑486.

  15. β淀粉样前体蛋白17肽对糖尿病大鼠海马神经细胞线粒体膜电位和凋亡的干预%APP17-mer peptide in regulation of neuronal mitochondrial transmembrane potentials and apoptosis in the hippocampus of diabetic rats

    Institute of Scientific and Technical Information of China (English)

    李红星; 王蓉; 杜怡峰; 姬志娟; 盛树力

    2005-01-01

    组高于糖尿病模型组[(705.99±89.92)道,P<0.05],与正常对照组相近(P=0.146).②海马单细胞凋亡率:糖尿病模型组明显高于正常对照组和β淀粉样前体蛋白17肽治疗组[(5.32±1.37)%,(1.03±0.55)%,(2.80±0.92)%,P<0.01,0.05].结论:海马线粒体膜电位下降和细胞的凋亡可能参与糖尿病脑病的发生发展;β淀粉样前体蛋白17肽具有改善这一病理过程的作用.%BACKGROUND: Learning and memory disorder exist in diabetic rats,which can be improved by APP 17-mer peptide. However, it is unclear whether learning and memory disorder in diabetes mellitus is caused by influencing neuronal mitochondrial transmembrane potentials and apoptosis in hippocampus or not and what is the related action mechanism of APP17-mer peptide.OBJECTIVE: To observe the effects of APP17-mer peptide on neuronal mitochondrial transmembrane potentials (△ψm) and apoptosis in hippocampal area of diabetic rats.DESIGN: A completely randomized, grouping and controlled trial.SETTING: Beijing Research Laboratory for Brain Aging, Beijing Xuanwu Hospital, Capital University of Medical Sciences; the Department of Endocrine, the First Central Hospital of Baoding.MATERIALS: The data measurement of the experiment was carried out in the Instrument Testing Center, the General Hospital of Chinese PLA between May 2002 and August 2002. The modeling and intervention of the experiment was carried out in the Animal Laboratory of Xuanwu Hospital, Capital University of Medical Sciences. Eighteen male Wistar rats were enrolled and randomized into control group, model group and APP17-mer peptide group with 6 rats in each group.METHODS: ① Diabetic models in the model and APP17-mer peptide groups were established by intraperitoneal injection of 60 mg/kg streptozotocin (pH=4.4) in fasted rats(fasting for 12 hours). Three days later, modeling was successful if blood sugar level in caudal vein was more than 15 mmol/L. Rats in the control group were not subjected to modeling.Then, the rats

  16. Metallothionein bioconjugates as delivery vehicles for bismuth-212 alpha particle therapy

    International Nuclear Information System (INIS)

    Macklis, R.M.; Morris, C.; Humm, J.; Hines, J.; Atcher, R.

    1991-01-01

    Metallothioneins (MTHs) are small cysteine-rich polypeptides that binds cationic metals at physiologic pH ranges through noncovalent -SH ligand interactions. Some leucine-rich renal MTHs have a particular avidity for bismuth. The authors have examined the ability of MTHs to selectively incorporate Bi-212, a short-lived high-energy alpha particle emitter currently under exploration as a potential therapeutic radiolabel for use in molecularly targeted cancer therapy. They find that under physiologic conditions, MTH will selectively incorporate Bi-212 after incubation with an equilibrium mixture of its upstream and downstream parents. The MTH moieties may be linked to tumor-binding macromolecules such as antibodies via thiolation reactions using SPDP, and the resultant Bismuth-avid molecules may be used either as primary delivery vehicles for the Bi-212 or as part of a 2-step release-and-catch isotope localization system in which the MTH-antibody conjugate is pre-localized at the tumor site and the radiometal is then administered and chelated in situ. They present the chemistry, dosimetry and potential clinical applications of this system

  17. Detection of Metallothionein in Javanese Medaka (Oryzias javanicus, Using a scFv-Immobilized Protein Chip

    Directory of Open Access Journals (Sweden)

    Euiyeon Lee

    2018-04-01

    Full Text Available Environmental pollution by various industrial chemicals and biological agents poses serious risks to human health. Especially, marine contamination by potentially toxic elements (PTEs has become a global concern in recent years. Many efforts have been undertaken to monitor the PTE contamination of the aquatic environment. However, there are few approaches available to assess the PTE exposure of aquatic organisms. In this research, we developed a strategy to evaluate the heavy metal exposure of marine organisms, by measuring the expression levels of metallothionein protein derived from Oryzias javanicus (OjaMT. OjaMT is a biomarker of heavy metal exposure because the expression level increases upon heavy metal exposure. The developed assay is based on a real-time, label-free surface plasmon resonance (SPR measurement. Anti-OjaMT antibody and anti-OjaMT single-chain fragment of variable region (scFv were used as detection probes. Two types of SPR sensor chips were fabricated, by immobilizing antibody or Cys3-tagged scFv (scFv-Cys3 in a controlled orientation and were tested for in situ label-free OjaMT detection. Compared to the antibody-presenting sensor chips, the scFv-presenting sensor chips showed improved performance, displaying enhanced sensitivity and enabling semi-quantitative detection. The portable SPR system combined with scFv-immobilized sensor chips is expected to provide an excellent point-of-care testing system that can monitor target biomarkers in real time.

  18. Mercury and metallothioneins in blood fractions and tissues of captive Morelet's crocodiles in Quintana Roo, Mexico.

    Science.gov (United States)

    Buenfil-Rojas, A M; Alvarez-Legorreta, T; Cedeño-Vázquez, J R

    2018-05-01

    Even though studies of heavy metals and their relation with metallothioneins (MTs) in reptile tissues have been conducted, research on heavy metals and MTs in organs and blood fractions of crocodylians is limited. To date there are no studies on the distribution of MTs in organs and their relation with mercury (Hg), or the concentration of MTs in plasma and erythrocytes of crocodylians. In order to understand the role of MTs in crocodiles, our aim was to assess the detoxification mechanisms for exposure to metals in Morelet's crocodile (Crocodylus moreletii) by using two biomarkers (Hg and MTs) in blood fractions and tissues, and comparing them with concentrations between two populations of crocodiles, one previously wild and currently captive (Theme Park) and another raised in a Wildlife Management Unit (WMU). The caudal scutes from the Theme Park showed higher concentrations of Hg than those from the skin in the WMU samples, and significant negative relationships were observed between the total length (TL) and Hg in the scutes. The significant negative relationship between Hg and hemoglobin (Hb) may be due to disorders in the oxidation process and even denature of this protein, while the positive trend observed between MTs and Hb is consistent with the detoxifying functions and the protection against oxidative damage. This study is the first to report Hg in the erythrocytes of crocodylians and the use of MTs for testing the potential of these biomarkers as a tool to assess Hg exposure in crocodile's habitats. Copyright © 2018 Elsevier Ltd. All rights reserved.

  19. Metallothionein as potential biomarker of cadmium exposure in Persian sturgeon (Acipenser persicus).

    Science.gov (United States)

    Shariati, Fatemeh; Esaili Sari, Abbas; Mashinchian, Ali; Pourkazemi, Mohammad

    2011-10-01

    Metallothionein (MT) concentration in gills, liver, and kidney tissues of Persian sturgeon (Acipenser persicus) were determined following exposure to sublethal levels of waterborne cadmium (Cd) (50, 400, and 1,000 μg l(-1)) after 1, 2, 4, and 14 days. The increases of MT from background levels were 4.6-, 3-, and 2.8-fold for kidney, liver, and gills, respectively. The results showed that MT level change in the kidney is time and concentration dependent. Also, cortisol measurement revealed elevation at the day 1 of exposure and followed by MT increase in the liver. Cd concentrations in the cytosol of experimental tissues were measured, and the results indicated that Cd levels in the cytosol of liver, kidney, and gills increased 240.71-, 32.05-, and 40.16-fold, respectively, 14 days after exposure to 1,000 μg l(-1) Cd. The accumulation of Cd in cytosol of tissues is in the order of liver > gills > kidney. Pearson correlation coefficients showed that the MT content in kidney is correlated with Cd concentration, the value of which is more than in liver and gills. Thus, kidney can be considered as a tissue indicator in A. persicus for waterborne Cd contamination.

  20. Metallothionein-1 and nitric oxide expression are inversely correlated in a murine model of Chagas disease

    Directory of Open Access Journals (Sweden)

    Martha Elba Gonzalez-Mejia

    2014-04-01

    Full Text Available Chagas disease, caused by Trypanosoma cruzi, represents an endemic among Latin America countries. The participation of free radicals, especially nitric oxide (NO, has been demonstrated in the pathophysiology of seropositive individuals with T. cruzi. In Chagas disease, increased NO contributes to the development of cardiomyopathy and megacolon. Metallothioneins (MTs are efficient free radicals scavengers of NO in vitro and in vivo. Here, we developed a murine model of the chronic phase of Chagas disease using endemic T. cruzi RyCH1 in BALB/c mice, which were divided into four groups: infected non-treated (Inf, infected N-monomethyl-L-arginine treated (Inf L-NAME, non-infected L-NAME treated and non-infected vehicle-treated. We determined blood parasitaemia and NO levels, the extent of parasite nests in tissues and liver MT-I expression levels. It was observed that NO levels were increasing in Inf mice in a time-dependent manner. Inf L-NAME mice had fewer T. cruzi nests in cardiac and skeletal muscle with decreased blood NO levels at day 135 post infection. This affect was negatively correlated with an increase of MT-I expression (r = -0.8462, p < 0.0001. In conclusion, we determined that in Chagas disease, an unknown inhibitory mechanism reduces MT-I expression, allowing augmented NO levels.

  1. Bioadsorption of cadmium ion by cell surface-engineered yeasts displaying metallothionein and hexa-His

    Energy Technology Data Exchange (ETDEWEB)

    Kuroda, K.; Ueda, M. [Lab. of Applied Biological Chemistry, Kyoto Univ., Yoshida, Kyoto (Japan)

    2004-07-01

    The Cd{sup 2+}-chelating abilities of yeast metallothionein (YMT) and hexa-His displayed on the yeast-cell surface were compared. Display of YMT and hexa-His by {alpha}-agglutinin-based cell-surface engineering was confirmed by immunofluorescent labeling. Surface-engineered yeast cells with YMT and hexa-His fused in tandem showed superior cell-surface adsorption and recovery of Cd{sup 2+} under EDTA treatment on the cell surface than hexa-His-displaying cells. YMT was demonstrated to be more effective than hexa-His for the adsorption of Cd{sup 2+}. Yeast cells displaying YMT and/or hexa-His exhibited a higher potential for the adsorption of Cd{sup 2+} than Escherichia coli cells displaying these molecules. In order to investigate the effect of the displayed YMT and hexa-His on sensitivity to toxic Cd{sup 2+}, growth in Cd{sup 2+}-containing liquid medium was monitored. Unlike hexa-His-displaying cells, cells displaying YMT and hexa-His fused in tandem induced resistance to Cd{sup 2+} through active and enhanced adsorption of toxic Cd{sup 2+}. These results indicate that YMT-displaying yeast cells are a unique bioadsorbent with a functional chelating ability superior to that of E. coli. (orig.)

  2. Immunoelectron microscopic studies on metallothionein induction in Nile cichlid due to heavy metal stress

    International Nuclear Information System (INIS)

    Chatterjee, S.; Singh, L.; Das, T.K.; Mukhopadhyay, S.K.

    2010-01-01

    Heavy metals are important environmental pollutants and many of them are toxic even in low concentrations. The uncontrolled input of such elements in milieu is undesirable because once accumulated, are hard to remove. The release of toxic metals in biologically available forms by human activity may damage or alter both natural and man-made ecosystems. The cellular adaptation to toxicity of metals is one of the important factors for organisms living in the stressful conditions. The major type of cellular effect at the cytoplasmic level involves binding of metals through specific metal binding proteins. One of these metalloproteins is metallothionein (MT), MT is a low-molecular-weight (6-7 kDa) cysteine rich protein ubiquitous in the animal kingdom and can bind with essential (Cu + and Zn 2+ ) and nonessential (Cd 2+ , Hg 2+ and Ag + ) metals with a high thermodynamic and low kinetic stability. Again, the induction of MT by other heavy metals such as Cr, Mn and Pb was also reported by several workers

  3. Metallothioneins and trace metals in the dogwhelk Nucella lapillus (L.) collected from Icelandic coasts

    Energy Technology Data Exchange (ETDEWEB)

    Leung, Kenneth M.Y. [Sandgeroi Marine Centre, Garovegi 1, 245 Sandgeroi (Iceland)]. E-mail: kmyleung@hkucc.hku.hk; Dewhurst, Rachel E. [School of Biological Sciences, Royal Holloway, University of London, Egham, Surrey TW20 0EX (United Kingdom); Halldorsson, Halldor [Sandgeroi Marine Centre, Garovegi 1, 245 Sandgeroi (Iceland); Institute of Biology, University of Iceland, Sturlugata 7, 101 Reykjavik (Iceland); Svavarsson, Joerundur [Sandgeroi Marine Centre, Garovegi 1, 245 Sandgeroi (Iceland); Institute of Biology, University of Iceland, Sturlugata 7, 101 Reykjavik (Iceland)

    2005-07-01

    Different sizes of the dogwhelk Nucella lapillus were collected from eight locations along the southwest and north coasts of Iceland. Concentrations of total metallothioneins (MTs) and heavy metals (Cd, Cu, Cr, Mn, Ni, and Zn) were analysed using the silver saturation method and inductively coupled plasma-atomic emission spectrometry. The level of tributyltin (TBT) contamination was also assessed using imposex indices, the vas deferens stage index (VDSI) and relative penis size index (RPSI). Gufunes N. lapillus presented the highest values of VDSI (4.0) and RPSI (11.1), followed by Grenivik individuals (VDSI = 3.0; RPSI = 0.9), while the Strandakirkja population showed the lowest VDSI (0.3) and zero RPSI. At a standardised size (0.25 g dry soft-body weight), Grenivik N. lapillus exhibited significantly higher concentrations of all metals whereas overall metal concentrations were significantly lower in individuals from Strandakirkja and Garoskagi compared to other study sites. Partial correlation analyses with size correction indicated that MT concentrations were better correlated with Cd and Cu concentrations than with other metals. At the standard size, the pattern of MT concentrations in N. lapillus from different sites was, however, very different from those of metal profiles. Such discrepancies between the patterns of MT and metals in N. lapillus might be explained by the fact that MT induction could be influenced by various factors such as temperature, dietary metal intake, growth rate and co-existence of other MT-inducing chemicals.

  4. Metallothioneins and trace metals in the dogwhelk Nucella lapillus (L.) collected from Icelandic coasts

    International Nuclear Information System (INIS)

    Leung, Kenneth M.Y.; Dewhurst, Rachel E.; Halldorsson, Halldor; Svavarsson, Joerundur

    2005-01-01

    Different sizes of the dogwhelk Nucella lapillus were collected from eight locations along the southwest and north coasts of Iceland. Concentrations of total metallothioneins (MTs) and heavy metals (Cd, Cu, Cr, Mn, Ni, and Zn) were analysed using the silver saturation method and inductively coupled plasma-atomic emission spectrometry. The level of tributyltin (TBT) contamination was also assessed using imposex indices, the vas deferens stage index (VDSI) and relative penis size index (RPSI). Gufunes N. lapillus presented the highest values of VDSI (4.0) and RPSI (11.1), followed by Grenivik individuals (VDSI = 3.0; RPSI = 0.9), while the Strandakirkja population showed the lowest VDSI (0.3) and zero RPSI. At a standardised size (0.25 g dry soft-body weight), Grenivik N. lapillus exhibited significantly higher concentrations of all metals whereas overall metal concentrations were significantly lower in individuals from Strandakirkja and Garoskagi compared to other study sites. Partial correlation analyses with size correction indicated that MT concentrations were better correlated with Cd and Cu concentrations than with other metals. At the standard size, the pattern of MT concentrations in N. lapillus from different sites was, however, very different from those of metal profiles. Such discrepancies between the patterns of MT and metals in N. lapillus might be explained by the fact that MT induction could be influenced by various factors such as temperature, dietary metal intake, growth rate and co-existence of other MT-inducing chemicals

  5. Metal contamination in harbours impacts life-history traits and metallothionein levels in snails.

    Directory of Open Access Journals (Sweden)

    Maria Alexandra Bighiu

    Full Text Available Harbours with limited water exchange are hotspots of contaminant accumulation. Antifouling paints (AF contribute to this accumulation by leaching biocides that may affect non-target species. In several leisure boat harbours and reference areas in the Baltic Sea, chronic exposure effects were evaluated using caging experiments with the snail Theodoxus fluviatilis. We analysed variations in ecologically relevant endpoints (mortality, growth and reproduction in concert with variation in metallothionein-like proteins (MTLP levels. The latter is a biomarker of exposure to metals, such as copper (Cu and zinc (Zn, which are used in AF paints as active ingredient and stabilizer, respectively. In addition, environmental samples (water, sediment were analysed for metal (Cu and Zn and nutrient (total phosphorous and nitrogen concentrations. All life-history endpoints were negatively affected by the exposure, with higher mortality, reduced growth and lower fecundity in the harbours compared to the reference sites. Metal concentrations were the key explanatory variables for all observed adverse effects, suggesting that metal-driven toxicity, which is likely to stem from AF paints, is a source of anthropogenic stress for biota in the harbours.

  6. The influence of biological and environmental factors on metallothionein concentration in the blood.

    Science.gov (United States)

    Kowalska, Katarzyna; Bizoń, Anna; Zalewska, Marta; Milnerowicz, Halina

    2015-01-01

    The concentration of metallothionein (MT), a low-molecular-weight protein, is regulated by many factors, primarily metals (zinc, cadmium, copper), cytokines, glucocorticoides and free radicals. These factors are determined by such aspects of human biology as gender, pregnancy and age, as well as by environmental factors including the use of oral contraceptives and cigarette smoking, all which may affect MT levels in the body. The aim of this study was to investigate the influence of these biological and environmental factors on MT concentrations in erythrocyte lysate and in plasma. MT concentrations were determined by a two-step direct enzyme-linked immunosorbent assay. Evaluation of exposure to cigarette smoking was performed by checking cotinine levels in the plasma of subjects. The studies showed higher MT concentrations in both the erythrocyte lysate and plasma of women when compared to men. Furthermore, pregnancy causes an increase of MT concentration in plasma, while oral contraceptives cause an elevated concentration of MT in erythrocyte lysate. Age impacts plasma MT concentrations in men, whereas it does not affect concentrations of MT in erythrocyte lysate. Copyright © 2014 Elsevier GmbH. All rights reserved.

  7. Decoupling of cadmium biokinetics and metallothionein turnover in a marine polychaete after metal exposure

    Energy Technology Data Exchange (ETDEWEB)

    Ng, Tania Y.-T. [Department of Biology, Hong Kong University of Science and Technology (HKUST), Clear Water Bay, Kowloon, Hong Kong (China); Rainbow, Philip S. [Department of Zoology, Natural History Museum, Cromwell Road, London SW7 5BD (United Kingdom); Amiard-Triquet, Claude; Amiard, Jean-Claude [Universite de Nantes, Faculte de Pharmacie, MMS EA2160, Service d' ecotoxicologie, F-44000 Nantes (France); Wang Wenxiong [Department of Biology, Hong Kong University of Science and Technology (HKUST), Clear Water Bay, Kowloon, Hong Kong (China)], E-mail: wwang@ust.hk

    2008-08-11

    This study investigated the kinetics of Cd bioaccumulation, detoxification, subcellular distribution, and efflux in the nereid polychaete Perinereis aibuhitensis after Cd pre-exposure. Cd pre-exposure increased the Cd body burden in the worms, but did not affect the overall Cd uptake and efflux rates and metallothionein-like protein (MTLP) concentrations. During short-term exposure to dissolved Cd, Cd in the cytosolic fraction increased after Cd pre-exposure, and this fraction also increased during the Cd efflux period, indicating that the insoluble fraction of Cd was presumably lost at a faster rate than the loss of cytosolic Cd. Even though the MTLP concentration remained comparable after Cd pre-exposure, both the MTLP synthesis rate and the degradation rate increased, thus leading to a high MTLP turnover in the Cd-exposed worms. However, Cd uptake and efflux into different protein size fractions did not follow the patterns of MTLP synthesis and degradation, strongly suggesting that Cd kinetics is decoupled from the MTLP kinetics in the worms. Our study adds to an increasing body of evidence on the complicated relationship between metal biokinetics and MTLP kinetics in different groups of marine invertebrates which have strong contrasts in their metal handling strategies.

  8. Gene expression profiling in wild-type and metallothionein mutant fibroblast cell lines

    Directory of Open Access Journals (Sweden)

    ÁNGELA D ARMENDÁRIZ

    2006-01-01

    Full Text Available The role of metallothioneins (MT in copper homeostasis is of great interest, as it appears to be partially responsible for the regulation of intracellular copper levels during adaptation to extracellular excess of the metal. To further investigate a possible role of MTs in copper metabolism, a genomics approach was utilized to evaluate the role of MT on gene expression. Microarray analysis was used to examine the effects of copper overload in fibroblast cells from normal and MT I and II double knock-out mice (MT-/-. As a first step, we compared genes that were significantly upregulated in wild-type and MT-/- cells exposed to copper. Even though wild-type and mutant cells are undistinguishable in terms of their morphological features and rates of growth, our results show that MT-/- cells do not respond with induction of typical markers of cellular stress under copper excess conditions, as observed in the wild-type cell line, suggesting that the transcription initiation rate or the mRNA stability of stress genes is affected when there is an alteration in the copper store capacity. The functional classification of other up-regulated genes in both cell lines indicates that a large proportion (>80% belong to two major categories: 1 metabolism; and 2 cellular physiological processes, suggesting that at the transcriptional level copper overload induces the expression of genes associated with diverse molecular functions. These results open the possibility to understand how copper homeostasis is being coordinated with other metabolic pathways.

  9. High Glucose Increases Metallothionein Expression in Renal Proximal Tubular Epithelial Cells

    Directory of Open Access Journals (Sweden)

    Daisuke Ogawa

    2011-01-01

    Full Text Available Metallothionein (MT is an intracellular metal-binding, cysteine-rich protein, and is a potent antioxidant that protects cells and tissues from oxidative stress. Although the major isoforms MT-1 and -2 (MT-1/-2 are highly inducible in many tissues, the distribution and role of MT-1/-2 in diabetic nephropathy are poorly understood. In this study, diabetes was induced in adult male rats by streptozotocin, and renal tissues were stained with antibodies for MT-1/-2. MT-1/-2 expression was also evaluated in mProx24 cells, a mouse renal proximal tubular epithelial cell line, stimulated with high glucose medium and pretreated with the antioxidant vitamin E. MT-1/-2 expression was gradually and dramatically increased, mainly in the proximal tubular epithelial cells and to a lesser extent in the podocytes in diabetic rats, but was hardly observed in control rats. MT-1/-2 expression was also increased by high glucose stimulation in mProx24 cells. Because the induction of MT was suppressed by pretreatment with vitamin E, the expression of MT-1/-2 is induced, at least in part, by high glucose-induced oxidative stress. These observations suggest that MT-1/-2 is induced in renal proximal tubular epithelial cells as an antioxidant to protect the kidney from oxidative stress, and may offer a novel therapeutic target against diabetic nephropathy.

  10. Intracellular metabolism and effects of circulating cadmium-metallothionein in the kidney

    Energy Technology Data Exchange (ETDEWEB)

    Squibb, K.S.; Fowler, B.A.

    1984-03-01

    The mechanism of cadmium-metallothionein (CdMT)-mediated nephrotoxicity is being studied in rats using an acute dose regimen. Results of metabolism studies have shown that injected CdMT is rapidly degraded by the kidney with the release of Cd/sup 2 +/ into the cell cytoplasm. Ultrastructural studies indicate that an increase in the number of small lysosomes is the first measurable effect of CdMT in the kidney at 1 hr. This is followed by an increase in the number of small vesicles at 4 hr. It is proposed that these effects are the result of decreased primary lysosome formation and an inhibition of the fusion of pinocytotic vesicles with cell lysosomes by Cd. Functional alterations measured 8 hr after CdMT injection include an increase in urine volume and increased excretion of the low molecular weight protein, RNAase. Prior induction of renal MT by Zn pretreatment prevents the induction of polyuria and low molecular weight proteinuria by CdMT. These data provide further evidence that CdMT nephrotoxicity occurs as a result of Cd/sup 2 +/ toxicity within the cell. 25 references, 3 figures.

  11. Impact of intracellular metallothionein on metal biouptake and partitioning dynamics at bacterial interfaces.

    Science.gov (United States)

    Présent, Romain M; Rotureau, Elise; Billard, Patrick; Pagnout, Christophe; Sohm, Bénédicte; Flayac, Justine; Gley, Renaud; Pinheiro, José P; Duval, Jérôme F L

    2017-11-08

    Genetically engineered microorganisms are alternatives to physicochemical methods for remediation of metal-contaminated aquifers due to their remarkable bioaccumulation capacities. The design of such biosystems would benefit from the elaboration of a sound quantitative connection between performance in terms of metal removal from aqueous solution and dynamics of the multiscale processes leading to metal biouptake. In this work, this elaboration is reported for Escherichia coli cells modified to overexpress intracellular metallothionein (MTc), a strong proteinaceous metal chelator. Depletion kinetics of Cd(ii) from bulk solution following biouptake and intracellular accumulation is addressed as a function of cell volume fraction using electroanalytical probes and ligand exchange-based analyses. It is shown that metal biouptake in the absence and presence of MTc is successfully interpreted on the basis of a formalism recently developed for metal partitioning dynamics at biointerfaces with integration of intracellular metal speciation. The analysis demonstrates how fast sequestration of metals by intracellular MTc bypasses metal excretion (efflux) and enhances the rate of metal depletion to an extent such that complete removal is achieved at sufficiently large cell volume fractions. The magnitude of the stability constant of nanoparticulate metal-MTc complexes, as derived from refined analysis of macroscopic bulk metal depletion data, is further confirmed by independent electrochemical measurement of metal binding by purified MTc extracts.

  12. Decoupling of cadmium biokinetics and metallothionein turnover in a marine polychaete after metal exposure

    International Nuclear Information System (INIS)

    Ng, Tania Y.-T.; Rainbow, Philip S.; Amiard-Triquet, Claude; Amiard, Jean-Claude; Wang Wenxiong

    2008-01-01

    This study investigated the kinetics of Cd bioaccumulation, detoxification, subcellular distribution, and efflux in the nereid polychaete Perinereis aibuhitensis after Cd pre-exposure. Cd pre-exposure increased the Cd body burden in the worms, but did not affect the overall Cd uptake and efflux rates and metallothionein-like protein (MTLP) concentrations. During short-term exposure to dissolved Cd, Cd in the cytosolic fraction increased after Cd pre-exposure, and this fraction also increased during the Cd efflux period, indicating that the insoluble fraction of Cd was presumably lost at a faster rate than the loss of cytosolic Cd. Even though the MTLP concentration remained comparable after Cd pre-exposure, both the MTLP synthesis rate and the degradation rate increased, thus leading to a high MTLP turnover in the Cd-exposed worms. However, Cd uptake and efflux into different protein size fractions did not follow the patterns of MTLP synthesis and degradation, strongly suggesting that Cd kinetics is decoupled from the MTLP kinetics in the worms. Our study adds to an increasing body of evidence on the complicated relationship between metal biokinetics and MTLP kinetics in different groups of marine invertebrates which have strong contrasts in their metal handling strategies

  13. Metallothionein is induced and trace element balance changed in target organs of a common viral infection

    International Nuclear Information System (INIS)

    Ilbaeck, Nils-Gunnar; Glynn, Anders W.; Wikberg, Lotta; Netzel, Elvy; Lindh, Ulf

    2004-01-01

    In experimental studies on the common human coxsackievirus B type 3 (CB3) infection, administered cadmium (Cd) is known to accumulate in the liver and kidneys. CB3 adapted to Balb/c mice was used to study whether infection affects the Cd-binding protein, metallothionein (MT) and if this alters the normal physiological trace element balance in the liver, kidney, spleen and brain. On day 3 of infection, degradation of liver proteins (44%, P<0.01) occurred, whereas in the spleen, protein increased (63%, P<0.05). The infection increased MT five-fold (P<0.01) in liver and kidneys, and in spleen by 34% (P<0.05). A redistribution of Cd and copper (Cu) from the liver to the kidney was associated with this increase in MT, resulting in an increased (P<0.01) kidney/liver ratio for both elements. The infection increased the zinc (Zn) concentration more in the kidney than in the liver, but the kidney/liver ratio was not significantly affected. Results show that MT is increased in several organs during the early phase of infection and is associated with redistribution of both essential and non-essential trace elements. This may be a normal response in common infections that could adversely influence the pathogenesis when the host is concomitantly exposed to potentially toxic trace elements, even at levels in the physiological range

  14. Spatial learning depends on both the addition and removal of new hippocampal neurons.

    Directory of Open Access Journals (Sweden)

    David Dupret

    2007-08-01

    Full Text Available The role of adult hippocampal neurogenesis in spatial learning remains a matter of debate. Here, we show that spatial learning modifies neurogenesis by inducing a cascade of events that resembles the selective stabilization process characterizing development. Learning promotes survival of relatively mature neurons, apoptosis of more immature cells, and finally, proliferation of neural precursors. These are three interrelated events mediating learning. Thus, blocking apoptosis impairs memory and inhibits learning-induced cell survival and cell proliferation. In conclusion, during learning, similar to the selective stabilization process, neuronal networks are sculpted by a tightly regulated selection and suppression of different populations of newly born neurons.

  15. An Effect of Cadmium and Lead Ions on Escherichia coli with the Cloned Gene for Metallothionein (MT-3) Revealed by Electrochemistry

    International Nuclear Information System (INIS)

    Adam, Vojtech; Chudobova, Dagmar; Tmejova, Katerina; Cihalova, Kristyna; Krizkova, Sona; Guran, Roman; Kominkova, Marketa; Zurek, Michal; Kremplova, Monika; Jimenez, Ana Maria Jimenez; Konecna, Marie

    2014-01-01

    This study was focused on the application of electrochemical methods for studying of bacterial strains Escherichia coli and Escherichia coli expressing human metallothionein gene (MT-3) before and after the application of cadmium and/or lead ions in four concentrations (25, 50, 75 and 150 μM). Bacterial strains Escherichia coli and Escherichia coli expressing human metallothionein gene (MT-3) were used like model organisms for studying of metals influence to metallothionein expression. Metallothionein was isolated using fast protein liquid chromatography and quantified by electrochemical methods. The occurrence of metallothionein in E.coli was confirmed by gel electrophoresis by the presence of the bands at 15 (MT dimer) and 22 kDa (MT trimer). The changes in electrochemical records due to the interactions of metallothioneins (MT-3 and MT-2A) with cadmium and lead ions showed decline of Cat2 signal of MT with the increasing interaction time because of metal ions binding to cysteines. Electrochemical determination also revealed that Cd(II) remains in E. coli cells in the higher amount than Pb (II). Opposite situation was found at E. coli–MT-3 strain. The antimicrobial effect of cadmium ions was determined by IC 50 and was statistically calculated as 39.2 and 95.5 μM for E. coli without cloned MT-3 and E. coli carrying MT-3 gene, respectively. High provided concentration IC 50 in strains after lead ions application (352.5 μM for E. coli without cloning and 207.0 μM for E. coli carrying cloned MT-3 gene) indicates lower toxicity of lead ions on bacterial strains compared to the cadmium ions

  16. Fullerene and apoptosis

    Directory of Open Access Journals (Sweden)

    M. A. Orlova

    2013-01-01

    Full Text Available Fullerene derivatives superfamily attracts a serious attention as antiviral and anticancer agents and drug delivery carriers as well. A large number of such fullerene С60 derivatives obtained to date. However, there is an obvious deficit of information about causes and mechanisms of immediately and long-term consequences of their effects in vivo which is a true obstacle on the way leading to practical medical use of them. First, this concerns their impact on the proliferation, apoptosis and necrosis regulation. Fullerene nanoparticle functionalization type, their sizes and surface nanopathology are of great importance to further promoting of either cytoprotective or cytotoxic effects. This lecture provides modern concept analysis regarding fullerenes effects on apoptosis pathway in normal and tumor cells.

  17. Cl- channels in apoptosis

    DEFF Research Database (Denmark)

    Wanitchakool, Podchanart; Ousingsawat, Jiraporn; Sirianant, Lalida

    2016-01-01

    A remarkable feature of apoptosis is the initial massive cell shrinkage, which requires opening of ion channels to allow release of K(+), Cl(-), and organic osmolytes to drive osmotic water movement and cell shrinkage. This article focuses on the role of the Cl(-) channels LRRC8, TMEM16/anoctamin......, and cystic fibrosis transmembrane conductance regulator (CFTR) in cellular apoptosis. LRRC8A-E has been identified as a volume-regulated anion channel expressed in many cell types. It was shown to be required for regulatory and apoptotic volume decrease (RVD, AVD) in cultured cell lines. Its presence also......(-) channels or as regulators of other apoptotic Cl(-) channels, such as LRRC8. CFTR has been known for its proapoptotic effects for some time, and this effect may be based on glutathione release from the cell and increase in cytosolic reactive oxygen species (ROS). Although we find that CFTR is activated...

  18. The neuroprotective role and mechanisms of TERT in neurons with oxygen-glucose deprivation.

    Science.gov (United States)

    Li, J; Qu, Y; Chen, D; Zhang, L; Zhao, F; Luo, L; Pan, L; Hua, J; Mu, D

    2013-11-12

    Telomerase reverse transcriptase (TERT) is reported to protect neurons from apoptosis induced by various stresses including hypoxia-ischemia (HI). However, the mechanisms by which TERT exerts its anti-apoptotic role in neurons with HI injury remain unclear. In this study, we examined the protective role and explored the possible mechanisms of TERT in neurons with HI injury in vitro. Primary cultured neurons were exposed to oxygen and glucose deprivation (OGD) for 3h followed by reperfusion to mimic HI injury in vivo. Plasmids containing TERT antisense, sense nucleotides, or mock were transduced into neurons at 48h before OGD. Expression and distribution of TERT were measured by immunofluorescence labeling and western blot. The expression of cleaved caspase 3 (CC3), Bcl-2 and Bax were detected by western blot. Neuronal apoptosis was measured with terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL). The mitochondrial reactive oxygen species (ROS) were measured by MitoSOX Red staining. Fluorescent probe JC-1 was used to measure the mitochondrial membrane potential (ΔΨm). We found that TERT expression increased at 8h and peaked at 24h in neurons after OGD. CC3 expression and neuronal apoptosis were induced and peaked at 24h after OGD. TERT inhibition significantly increased CC3 expression and neuronal apoptosis after OGD treatment. Additionally, TERT inhibition decreased the expression ratio of Bcl-2/Bax, and enhanced ROS production and ΔΨm dissipation after OGD. These data suggest that TERT plays a neuroprotective role via anti-apoptosis in neurons after OGD. The underlying mechanisms may be associated with regulating Bcl-2/Bax expression ratio, attenuating ROS generation, and increasing mitochondrial membrane potential. Copyright © 2013 IBRO. Published by Elsevier Ltd. All rights reserved.

  19. The metal-binding function of metallothioneins and the state of antioxidant defense of carp gills under water pollution by heavy metals

    International Nuclear Information System (INIS)

    Stolyar, O.B.; Fal'fushins'ka, G.Yi.; Arsan, V.O.

    2005-01-01

    To investigate the influence of waterborne heavy metal ions on the metal-binding function of metallothioneins and the antioxidant defence in gills, carp (Cyprinus carpio L.) was exposed to copper, zinc, manganese, and lead ions in environmentally realistic concentrations (0.01, 0.1, 0.12, and 0.01 mg/l, respectively) or their mix for 14 days. The results indicate that the metal poisoning provokes the changes in the copper, manganese, and zinc contents in gills and their distribution among the molecular forms of metallothioneins and another tissue targets

  20. Bioimaging of metallothioneins in ocular tissue sections by laser ablation-ICP-MS using bioconjugated gold nanoclusters as specific tags.

    Science.gov (United States)

    Cruz-Alonso, María; Fernandez, Beatriz; Álvarez, Lydia; González-Iglesias, Héctor; Traub, Heike; Jakubowski, Norbert; Pereiro, Rosario

    2017-12-18

    An immunohistochemical method is described to visualize the distribution of metallothioneins 1/2 (MT 1/2) and metallothionein 3 (MT 3) in human ocular tissue. It is making use of (a) antibodies conjugated to gold nanoclusters (AuNCs) acting as labels, and (b) laser ablation (LA) coupled to inductively coupled plasma - mass spectrometry (ICP-MS). Water-soluble fluorescent AuNCs (with an average size of 2.7 nm) were synthesized and then conjugated to antibody by carbodiimide coupling. The surface of the modified AuNCs was then blocked with hydroxylamine to avoid nonspecific interactions with biological tissue. Immunoassays for MT 1/2 and MT 3 in ocular tissue sections (5 μm thick) from two post mortem human donors were performed. Imaging studies were then performed by fluorescence using confocal microscopy, and LA-ICP-MS was performed in the retina to measure the signal for gold. Signal amplification by the >500 gold atoms in each nanocluster allowed the antigens (MT 1/2 and MT 3) to be imaged by LA-ICP-MS using a laser spot size as small as 4 μm. The image patterns found in retina are in good agreement with those obtained by conventional fluorescence immunohistochemistry which was used as an established reference method. Graphical abstract Gold nanoclusters (AuNCs) conjugated to a primary specific antibody serve as a label for amplified bioimaging of metallothioneins (MTs) by laser ablation coupled to inductively coupled plasma - mass spectrometry (ICP-MS) in human ocular tissue sections.

  1. Nuclear exclusion of transcription factors associated with apoptosis in developing nervous tissue

    Directory of Open Access Journals (Sweden)

    R. Linden

    1999-07-01

    Full Text Available Programmed cell death in the form of apoptosis involves a network of metabolic events and may be triggered by a variety of stimuli in distinct cells. The nervous system contains several neuron and glial cell types, and developmental events are strongly dependent on selective cell interactions. Retinal explants have been used as a model to investigate apoptosis in nervous tissue. This preparation maintains the structural complexity and cell interactions similar to the retina in situ, and contains cells in all stages of development. We review the finding of nuclear exclusion of several transcription factors during apoptosis in retinal cells. The data reviewed in this paper suggest a link between apoptosis and a failure in the nucleo-cytoplasmic partition of transcription factors. It is argued that the nuclear exclusion of transcription factors may be an integral component of apoptosis both in the nervous system and in other types of cells and tissues.

  2. Metallothionein-III protects against 6-hydroxydopamine-induced oxidative stress by increasing expression of heme oxygenase-1 in a PI3K and ERK/Nrf2-dependent manner

    International Nuclear Information System (INIS)

    Hwang, Yong Pil; Kim, Hyung Gyun; Han, Eun Hee; Jeong, Hye Gwang

    2008-01-01

    The zinc-binding protein metallothionein-III (MT-III) is associated with resistance to neuronal injury. However, the underlying mechanism for its effects is unclear. In this study, we demonstrate that MT-III prevents the accumulation of reactive oxygen species (ROS) in dopaminergic SH-SY5Y cells challenged with the Parkinson's disease-related neurotoxin 6-hydroxydopamine (6-OHDA) by a mechanism that involves phosphatidylinositol 3-kinase (PI3K) and ERK kinase/NF-E2-related factor 2 (Nrf2) dependent induction of the stress response protein heme oxygenase-1 (HO-1). Pretreatment of SH-SY5Y cells with MT-III significantly reduced 6-OHDA-induced generation of ROS, caspase-3 activation, and subsequent cell death. Also, MT-III up-regulates HO-1 expression and this expression confers neuroprotection against oxidative injury induced by 6-OHDA. Moreover, MT-III induces Nrf2 nuclear translocation, which is upstream of MT-III-induced HO-1 expression, and PI3K and ERK1/2 activation, a pathway that is involved in induced Nrf2 nuclear translocation, HO-1 expression and neuroprotection. Taken together, these results suggest that the PI3K and ERK/Nrf2 signaling pathway controls the intracellular levels of ROS by regulating the expression of the antioxidant enzyme HO-1

  3. The CUP2 gene product regulates the expression of the CUP1 gene, coding for yeast metallothionein.

    OpenAIRE

    Welch, J; Fogel, S; Buchman, C; Karin, M

    1989-01-01

    The yeast CUP1 gene codes for a copper-binding protein similar to metallothionein. Copper sensitive cup1s strains contain a single copy of the CUP1 locus. Resistant strains (CUP1r) carry 12 or more multiple tandem copies. We isolated 12 ethyl methane sulfonate-induced copper sensitive mutants in a wild-type CUP1r parental strain, X2180-1A. Most mutants reduce the copper resistance phenotype only slightly. However, the mutant cup2 lowers resistance by nearly two orders of magnitude. We cloned ...

  4. Treatment with metallothionein prevents demyelination and axonal damage and increases oligodendrocyte precursors and tissue repair during experimental autoimmune encephalomyelitis

    DEFF Research Database (Denmark)

    Penkowa, Milena; Hidalgo, Juan

    2003-01-01

    Experimental autoimmune encephalomyelitis (EAE) is an animal model for the human demyelinating disease multiple sclerosis (MS). EAE and MS are characterized by significant inflammation, demyelination, neuroglial damage, and cell death. Metallothionein-I and -II (MT-I + II) are antiinflammatory an......)beta, neurotrophin-3 (NT-3), NT-4/5, and nerve growth factor (NGF). These beneficial effects of Zn-MT-II treatment could not be attributable to its zinc content per se. The present results support further the use of Zn-MT-II as a safe and successful therapy for multiple sclerosis....

  5. Metallothionein-Like Proteins and Energy Reserve Levels after Ni and Pb Exposure in the Pacific White Prawn Penaeus vannamei

    Directory of Open Access Journals (Sweden)

    Gabriel Nunez-Nogueira

    2010-01-01

    Full Text Available This study analyzed the changes in metallothionein-like proteins (MTLPs and Energy Reserves (ERs in hepatopancreas and abdominal muscle of the white prawn Penaeus vannamei. Realistic metal concentration exposure for 10 days to Ni and Pb in solution revealed that juvenile prawns partially induce MTLP in hepatopancreas after Pb exposure. Ni was distributed equally between soluble and insoluble fractions, while Pb was present only in the insoluble fraction, suggesting different detoxification strategy. No changes in lipids and glycogen concentration were detected under these experimental conditions in both tissues analyzed. MTLP could not be considered as a suitable indicator for lead exposure in hepatopancreas.

  6. Metallothionein Abrogates GTP Cyclohydrolase I inhibition-Induced Cardiac Contractile and Morphological Defect: Role of Mitochondrial Biogenesis

    OpenAIRE

    Ceylan-Isik, Asli F.; Guo, Kelly K.; Carlson, Edward C.; Privratsky, Jamie R.; Liao, Song-Jie; Cai, Lu; Chen, Alex F.; Ren, Jun

    2009-01-01

    One key mechanism for endothelial dysfunction is eNOS uncoupling, whereby eNOS generates O2•− rather than NO, due to deficient eNOS cofactor tetrahydrobiopterin (BH4). This study was designed to examine the effect of BH4 deficiency on cardiac morphology and function as well as the impact of metallothionein (MT) on BH4 deficiency-induced abnormalities, if any. FVB and cardiac-specific MT transgenic mice were exposed to 2,4-diamino-6-hydroxy-pyrimidine (DAHP, 10 mmol/l, 3 wks), an inhibitor of ...

  7. Relative cadmium-binding capacity of metallothionein and other cytosolic fractions in various tissues of the rat

    International Nuclear Information System (INIS)

    Chen, R.W.; Ganther, H.E.

    1975-01-01

    The Cd-binding capacity of soluble proteins in 10 tissues of normal rats not excessively exposed to heavy metals was measured by saturation of freshly isolated cytosol with 109 CdCl 2 in vitro followed by Sephadex G-75 chromatography. The Cd-binding capacity of a 10,000 molecular weight Cd-binding peak (10,000 MW Cd-BP), which had a high affinity for Cd and was probably metallothionein, was the highest in kidney (78 nmol Cd/g fresh tissue), followed by testis (63 nmol/g), liver (38 nmol/g) and then by brain (14 nmol/g). The amount of the Cd-BP in these tissues (assuming that it was metallothionein and bound 9 mol Cd/10,000 g) was calculated to be 87, 70, 42 and 16 mg/kg fresh tissue in kidney, testis, liver and brain, respective-ly, or in the order of 10 -5 to 10 -6 mol/kg tissue. A significant amount of the 10,000 MW Cd-BP was also found in small intestine. It was present in rather small amounts in heart and lung, and possibly in spleen and skeletal muscle as well. In contrast, the protein was not detectable by this technique in plasma. The results suggest that metallothionein is a rather ubiquitous, intracellular protein in tissues of normal animals and may have other biological functions, besides its possible fortuitous role in heavy metal detoxification. A 30,000 molecular weight Cd-binding peak (30,000 MW Cd-BP) having a very high affinity to Cd, apparently higher than that of the 10,000 MW Cd-BP, was found only in testes, among the 10 tissues examined. Its estimated Cd-binding capacity was 51 nmol Cd/g of testis, slightly less than that of metallothionein in testis. These findings support the hypothesis that the 30,000 MW Cd-BP is a plausible target of Cd in Cd-induced testicular injury, and suggest a basis for the peculiar sensitivity of the rat testis to Cd. (author)

  8. Neuronal phosphorylated RNA-dependent protein kinase in Creutzfeldt-Jakob disease.

    LENUS (Irish Health Repository)

    Paquet, Claire

    2009-02-01

    The mechanisms of neuronal apoptosis in Creutzfeldt-Jakob disease (CJD) and their relationship to accumulated prion protein (PrP) are unclear. A recent cell culture study showed that intracytoplasmic PrP may induce phosphorylated RNA-dependent protein kinase (PKR(p))-mediated cell stress. The double-stranded RNA protein kinase PKR is a proapoptotic and stress kinase that accumulates in degenerating neurons in Alzheimer disease. To determine whether neuronal apoptosis in human CJD is associated with activation of the PKR(p) signaling pathway, we assessed in situ end labeling and immunocytochemistry for PrP, glial fibrillary acidic protein, CD68, activated caspase 3, and phosphorylated PKR (Thr451) in samples of frontal, occipital, and temporal cortex, striatum, and cerebellum from 6 patients with sporadic CJD and 5 controls. Neuronal immunostaining for activated PKR was found in all CJD cases. The most staining was in nuclei and, in contrast to findings in Alzheimer disease, cytoplasmic labeling was not detected. Both the number and distribution of PKR(p)-positive neurons correlated closely with the extent of neuronal apoptosis, spongiosis, astrocytosis, and microglial activation and with the phenotype and disease severity. There was no correlation with the type, topography, or amount of extracellular PrP deposits. These findings suggest that neuronal apoptosis in human CJD may result from PKR(p)-mediated cell stress and are consistent with recent studies supporting a pathogenic role for intracellular or transmembrane PrP.

  9. DETECTION OF OXIDATIVE STRESS, APOPTOSIS AND MOLECULAR LESIONS IN HUMAN OVARIAN CANCER CELLS

    Directory of Open Access Journals (Sweden)

    H. I. Falfushynska

    2016-05-01

    Full Text Available Background. Ovarian cancer has the highest mortality rate of gynaecological cancers. This is partly due to the lack of effective screening markers. Indices of oxidative stress are well-recognized prognostic criteria for tumorous transformation of tissue, but their value depends on the type of tumor and the stage of its development. Objective. The aim of this study is to clarify the relationship between antioxidant/pro-oxidant ratio and the signs of molecular lesions and apoptosis rate in blood of ovarian cancer patients and non-cancer ones. Results. The ovarian cancer group is marked by antioxidant/prooxidant balance shifting to oxidative damage in blood as the consequence of overexpression of oxyradicals (by 300%. Higher level of glutathione (by 366%, lower level of metallothioneins (by 65% as well as higher level of lipid peroxidation (by 174% and protein carbonyls (by 186% in blood of ovarian cancer patients compared to the normal ovarian group have been observed. The signs of cytotoxicity are determined in blood of ovarian cancer patients: an increased (compared to control level of DNA fragmentation (by 160%, choline esterase (up to twice, higher rate of both caspase dependent and caspase independent lysosomal mediated apoptosis. Conclusions. Cathepsin D activity both total and free, choline esterase activity, TBA-reactive substance and protein carbonyls level in blood could be used as the predictive markers of worse prognosis and the signs of human ovarian cancer.

  10. Gene response profiles for Daphnia pulex exposed to the environmental stressor cadmium reveals novel crustacean metallothioneins

    Directory of Open Access Journals (Sweden)

    Davey Jennifer C

    2007-12-01

    Full Text Available Abstract Background Genomic research tools such as microarrays are proving to be important resources to study the complex regulation of genes that respond to environmental perturbations. A first generation cDNA microarray was developed for the environmental indicator species Daphnia pulex, to identify genes whose regulation is modulated following exposure to the metal stressor cadmium. Our experiments revealed interesting changes in gene transcription that suggest their biological roles and their potentially toxicological features in responding to this important environmental contaminant. Results Our microarray identified genes reported in the literature to be regulated in response to cadmium exposure, suggested functional attributes for genes that share no sequence similarity to proteins in the public databases, and pointed to genes that are likely members of expanded gene families in the Daphnia genome. Genes identified on the microarray also were associated with cadmium induced phenotypes and population-level outcomes that we experimentally determined. A subset of genes regulated in response to cadmium exposure was independently validated using quantitative-realtime (Q-RT-PCR. These microarray studies led to the discovery of three genes coding for the metal detoxication protein metallothionein (MT. The gene structures and predicted translated sequences of D. pulex MTs clearly place them in this gene family. Yet, they share little homology with previously characterized MTs. Conclusion The genomic information obtained from this study represents an important first step in characterizing microarray patterns that may be diagnostic to specific environmental contaminants and give insights into their toxicological mechanisms, while also providing a practical tool for evolutionary, ecological, and toxicological functional gene discovery studies. Advances in Daphnia genomics will enable the further development of this species as a model organism for

  11. Effects of metallothionein on zinc metabolism in lethal-milk mutant mice

    International Nuclear Information System (INIS)

    Grider, A. Jr.

    1986-01-01

    The lethal-milk mice (C57BL/6J-Im) exhibit various pleiotropic effects, including a congenital otolith defect, production of zinc-deficient milk, and clinical signs of a systemic Zn deficiency by one year of age. The clinical signs include alopecia, dermatitis, and skin lesions. The systemic zinc deficiency may be due to increased levels of metallothionein (MT) in the intestine and/or liver of Im mice. The untreated Im mice contain twice as much intestinal MT as do C57BL/6J-(+/sup im//+ /sup Im/) (B6) controls. This was determined by a sulfhydryl assay, by the 109 Cd-saturation/hemolysate method, and by the 65 Zn-binding assay. Various concentrations of Cd or Zn were added to the drinking water three days before assaying for MT. Compared to B6 mice, the Im mice exhibited more MT in their liver by the 65 Zn-MT binding assay (3-fold) and by the 109 Cd-saturation/hemolysate method (18-fold). The effects of the two zinc treatments did not differ significantly between Im and B6 mice. The retention and excretion of 65 Zn (administered intraperitoneally) were determined over a 14-day period, but the results did not different between the Im and B6 mice. The increased concentrations of MT within the Im mice was not significantly different for the intestine and liver. Based on these data and other studies, the Im mice may exhibit alterations in zinc homeostasis due to some deregulation of MT metabolism, including the inner ear of the fetus, the lactating mammary gland, and the intestine and liver of adults by one year of age

  12. Metallothionein and antioxidant enzymes in Long-Evans Cinnamon rats treated with zinc

    Energy Technology Data Exchange (ETDEWEB)

    Medici, Valentina; Sturniolo, Giacomo Carlo; D' Inca, Renata [Department of Surgical and Gastroenterological Sciences, University of Padua, Padua (Italy); Santon, Alessandro; Giannetto, Sabrina; Albergoni, Vincenzo; Irato, Paola [Department of Biology, University of Padua, via U. Bassi 58/B, 35131 Padua (Italy)

    2002-09-01

    The Long-Evans Cinnamon (LEC) rat is a mutant animal model for Wilson's disease. It is known that an abnormal accumulation of Cu and Fe in the liver and low concentrations of both ceruloplasmin and Cu in the serum occur in these rats. The accumulation of Cu is explained by the defective expression of the Cu-transporting P-type ATPase gene, homologous to the gene for Wilson's disease (ATP7B). The aim of this work was to clarify the action mechanism of Zn, and to verify the role that this metal plays in LEC rats in short-term treatment experiments (1 and 2 weeks) on concentrations of Cu, Zn, Fe, metallothionein (MT), 8-hydroxy-2'-deoxyguanosine (oh{sup 8}dG) and on the activity of antioxidant enzymes. It is well known that Zn induces MT and has the ability to prevent redox-active metals, Cu and Fe, binding to and causing oxidative damage at active sites of Zn metalloenzymes and nonspecific binding sites on proteins. Zn administration reduces Cu and Fe transport from mucosal to serosal intestinal sides through competitive mechanisms. Our findings show that treatment with zinc acetate increases tissue Zn and MT contents and decreases Cu and Fe concentrations in the liver and kidneys, even if hepatic Zn and MT concentrations decrease with treatment period. Induction of MT synthesis by Zn contributes to the reduction in free radicals produced by Cu and Fe. We also observed that the superoxide dismutase (SOD)activity in liver decreases with treatment duration in association with the Cu and Fe liver decrease. However, the SOD activity in kidney increases in untreated rats at 2 weeks relative to those untreated for 1 week. (orig.)

  13. Alterations of metallothionein isomers in Hg{sup 0}-exposed rat brain

    Energy Technology Data Exchange (ETDEWEB)

    Yasutake, A. [Biochemistry Section, National Institute for Minamata Disease, Minamata, Kumamoto 867-0008 (Japan); Nagano, M. [Morikawa Kenkodo Co., Ltd., 2170 Taguchi, Kosa, Kamimashiki, Kumamoto 861-4616 (Japan); Hirayama, K. [Kumamoto University College of Medical Science, Kuhonji, Kumamoto 862-0976 (Japan)

    2003-01-01

    Previously we found that exposure to mercury vapor effectively induced brain metallothionein (MT) in rats. Here, using FPLC-gel chromatography, we examined time-dependent alterations in the MT isomers, MT-I/II and MT-III, following 3 weeks of exposure. Rats were exposed to mercury vapor at 8.3 mg/m{sup 3} for 15 h in total over 5 consecutive days. Total MT levels in rat cerebrum and cerebellum increased by 65% and 155%, respectively, 24 h after the final exposure. The increased levels in both tissues remained unchanged for at least 2 weeks after termination of exposure. Interestingly, most MT in control rat cerebrum and cerebellum was accounted for by MT-III, with MT-I/II being less than 10%. Through mercury vapor exposure, MT-I/II was quickly induced to a significant extent in both tissues, reaching a level comparable to that of MT-III. The induction rate of MT-I/II in the cerebellum was somewhat higher than in the cerebrum. Chromatograms showed that the MT-I/II thus induced began to decline at an early stage in both tissues. In the cerebrum, the amount of MT-I/II on day 22 was about 30% of the maximum level on day 1. On the other hand, the induction of MT-III was not that dramatic, but it did become evident, at least in the latter stage, when MT-I/II had begun to decrease. Thus, though the induction rate of MT-III was not as high as MT-I/II, it was sustained throughout the experimental period. (orig.)

  14. Effect of naturally mouldy wheat or fungi administration on metallothioneins level in brain tissues of rats.

    Science.gov (United States)

    Vasatkova, Anna; Krizova, Sarka; Krystofova, Olga; Adam, Vojtech; Zeman, Ladislav; Beklova, Miroslava; Kizek, Rene

    2009-01-01

    The aim of this study is to determine level of metallothioneins (MTs) in brain tissues of rats administered by feed mixtures with different content of mouldy wheat or fungi. Selected male laboratory rats of Wistar albino at age of 28 days were used in our experiments. The rats were administered by feed mixtures with different content of vitamins, naturally mouldy wheat or fungi for 28 days. At the very end of the experiment, the animals were put to death and brains were sampled. MT level was determined by differential pulse voltammetry Brdicka reaction. We found that MTs' level in brain tissues from rats administered by standard feed mixtures was significantly higher compared to the level of MTs in rats supplemented by vitamins. Further we studied the effect of supplementation of naturally mouldy wheat on MTs level in rats. In mouldy wheat we detected the presence of following fungi species: Mucor spp., Absidia spp., Penicillium spp., Aspergillus spp. and Fusarium spp. Moreover we also identified and quantified following mycotoxins - deoxynivalenol, zearalenone, T2-toxin and aflatoxins. Level of MTs determined in rats treated with 33 or 66% of mouldy wheat was significantly lower compared to control ones. On the other hand rats treated with 100% of mouldy wheat had less MTs but not significantly. Supplementation of vitamins to rats fed by mouldy wheat had adverse effect on MTs level compared to rats with no other supplementation by vitamins. Moreover vitamins supplementation has no effect on MTs level in brain tissues of rats treated or non-treated with Ganoderma lucidum L. Both mycotoxins and vitamins have considerable effect on level of MTs in brain tissues. It can be assumed that the administered substances markedly influence redox metabolism, which could negatively influence numerous biochemical pathways including those closely related with MTs.

  15. C-reactive protein in the hemolymph of Achatina fulica: interrelationship with sex steroids and metallothionein.

    Science.gov (United States)

    Bose, R; Bhattacharya, S

    2000-04-01

    C-reactive protein in Achatina fulica (ACRP) is a normal component of the hemolymph. Its concentration varied from 1mg/ml in the newly hatched male, 3-5 mg/ml in the most active hermaphrodite and 1.5-2.8 mg/ml in the sedentary female showing a direct relationship of the protein with the active phase of the animal. ACRP has a molecular mass of 400 kDa and showed high absorbance in the region of 200-230 nm. It has four subunits with relative molecular masses of 110, 90, 62 and 60 kDa, respectively. Interestingly, rat platelet aggregation in vitro was significantly enhanced by ACRP in presence of 10 microM ADP and 2 mM Ca(2+) suggesting a probable role of ACRP in the aggregation of amoebocytes during the formation of plug in injured tissue. Like other vertebrate CRPs, ACRP also acts as a scavenger of chromatin fragments as evidenced by its binding to poly-L-arginine. Among the sex steroids, 4-androstenedione induces ACRP synthesis in the newly hatched male reaching the level found in the most active hermaphrodite phase (4 mg/ml). A very high molar ratio (5) of mercury binding to ACRP confirmed its sequestration property of heavy metals as observed in vertebrates. The level of metallothionein (MT) in the hemolymph gradually increased from the male to the hermaphrodite to the female, a pattern distinctly different from that of the ACRP titer. Since both MT and ACRP can sequester inorganic mercury, the high level of MT compensates functionally for the low titer of ACRP in the sedentary female.

  16. Metal ion release from metallothioneins: proteolysis as an alternative to oxidation.

    Science.gov (United States)

    Peroza, Estevão A; dos Santos Cabral, Augusto; Wan, Xiaoqiong; Freisinger, Eva

    2013-09-01

    Metallothioneins (MTs) are among others involved in the cellular regulation of essential Zn(II) and Cu(I) ions. However, the high binding affinity of these proteins requires additional factors to promote metal ion release under physiological conditions. The mechanisms and efficiencies of these processes leave many open questions. We report here a comprehensive analysis of the Zn(II)-release properties of various MTs with special focus on members of the four main subfamilies of plant MTs. Zn(II) competition experiments with the metal ion chelator 4-(2-pyridylazo)resorcinol (PAR) in the presence of the cellular redox pair glutathione (GSH)/glutathione disulfide (GSSG) show that plant MTs from the subfamilies MT1, MT2, and MT3 are remarkably more affected by oxidative stress than those from the Ec subfamily and the well-characterized human MT2 form. In addition, we evaluated proteolytic digestion with trypsin and proteinase K as an alternative mechanism for selective promotion of metal ion release from MTs. Also here the observed percentage of liberated metal ions depends strongly on the MT form evaluated. Closer evaluation of the data additionally allowed deducing the thermodynamic and kinetic properties of the Zn(II) release processes. The Cu(I)-form of chickpea MT2 was used to exemplify that both oxidation and proteolysis are also effective ways to increase the transfer of copper ions to other molecules. Zn(II) release experiments with the individual metal-binding domains of Ec-1 from wheat grain reveal distinct differences from the full-length protein. This triggers the question about the roles of the long cysteine-free peptide stretches typical for plant MTs.

  17. Expression of Metallothionein and Vascular Endothelial Growth Factor Isoforms in Breast Cancer Cells.

    Science.gov (United States)

    Wierzowiecka, Barbara; Gomulkiewicz, Agnieszka; Cwynar-Zajac, Lucja; Olbromski, Mateusz; Grzegrzolka, Jedrzej; Kobierzycki, Christopher; Podhorska-Okolow, Marzenna; Dziegiel, Piotr

    2016-01-01

    Metallothioneins (MTs) are low-molecular-weight and cysteine-rich proteins that bind heavy metal ions and oxygen-free radicals. MTs are commonly expressed in various tissues of mammals and are involved in regulation of cell proliferation and differentiation, and may be engaged in angiogenesis. Expression of MTs has been studied in many cancer types, especially breast cancer. The research results indicate that MTs may play important, although not yet fully known, roles in cancer angiogenesis. The aim of this study was to analyze the level of gene expression of selected MT isoforms induced with zinc ions in correlation with vascular endothelial growth factor (VEGF) isoforms in in vitro models of breast cancer. The studies were carried out in three breast cancer cell lines (MCF-7, SK-BR-3, MDA-MB-231). An epithelial cell line derived from normal breast tissue (Me16c) was used as a control. The levels of expression of selected MT isoforms and selected genes involved in angiogenesis were studied with real-time PCR. Expression of different MT isoforms was induced by zinc ions to differing degrees in individual breast cancer cell lines. An increase in the expression of some MT isoforms was associated with a slight increase in the level of expression of VEGFA. The research results may indicate certain correlation between an increased expression of selected MT isoforms and a pro-angiogenic factor VEGF in specific types of breast cancer cells. Copyright © 2016 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

  18. Isolation and quantitation of metallothionein isoforms using reversed-phase high-performance liquid chromatography

    International Nuclear Information System (INIS)

    Richards, M.P.; Darcey, S.E.; Steele, N.C.

    1986-01-01

    Reversed-phase HPLC (RP-HPLC) was used to isolate and quantify metallothionein (MT) isoforms from a variety of animal species and tissues. Separations were performed on C 18 radially compressed cartridge columns, eluted with a 2-step linear gradient of acetonitrile in 10 mM sodium phosphate, pH 7.0. Isoforms were detected by UV absorbance (214 nm) and by on-line interfacing with an atomic absorption spectrophotometer (HPLC-AA) to determine bound Zn, Cd and Cu. Rabbit liver and horse kidney MT's exhibited 7 distinct peaks on RP-HPLC, 2 of which were predominant (MT1 and 2). Pig liver and kidney MT2 yielded 2 subspecies on RP-HPLC, while MT1 yielded a single peak. Avian liver MT was unique from mammalian MT's in that MT2 was about tenfold more abundant than MT1. RP-HPLC and HPLC-AA were used to isolate and quantitate MT isoforms and their Zn content directly from cytosol. Quantitation was achieved by peak area integration and extrapolation from a standard curve of purified avian liver MT2. Both RP-HPLC and HPLC-AA had a lower detection limit of 1 + g of peptide and .1 μg of Zn. Recoveries (92-98%) were determined with labeled ( 35 S) MT and MT of known Zn content. Cytoplasmic MT-Zn in avian embryo hepatocytes cultured with added Zn was quantitated using HPLC-AA. In conclusion, both RP-HPLC and HPLC-AA are rapid and powerful separation techniques for the isolation, quantitation and characterization of the isoproteins comprising the MT gene family

  19. Diurnal-and sex-related difference of metallothionein expression in mice

    Directory of Open Access Journals (Sweden)

    Zhang Dan

    2012-07-01

    Full Text Available Abstract Background Metallothionein (MT is a small, cysteine-rich, metal-binding protein that plays an important role in protecting against toxicity of heavy metal and chemicals. This study was aimed to define diurnal and sex variation of MT in mice. Methods Adult mice were maintained in light- and temperature-controlled facilities for 2 weeks with light on at 8:00 and light off at 20:00. The blood, liver, and kidneys were collected every 4 h during the 24 h period. Total RNA was isolated, purified, and subjected to real-time RT-PCR analysis and MT protein was determined by western blot and the Cd/hemoglobin assay. Results The diurnal variations in mRNA levels of MT-1 and MT-2in liver were dramatic, up to a 40-foldpeak/trough ratio. MT mRNA levels in kidneys and blood also showed diurnal variation, up to 5-fold peak/trough ratio. The diurnal variation of MT mRNAs resembled the clock gene albumin site D-binding protein (Dbp, and was anti-phase to the clock gene Brain and Muscle ARNT-like Protein 1 (Bmal1 in liver and kidneys. The peaks of MT mRNA levels were higher in females than in males. Hepatic MT protein followed a similar pattern, with about a 3-fold difference. Conclusion MT mRNA levels and protein showed diurnal- and sex-variation in liver, kidney, and blood of mice, which could impact the body defense against toxic stimuli.

  20. Metallothionein (MT) response after chronic palladium exposure in the zebra mussel, Dreissena polymorpha

    International Nuclear Information System (INIS)

    Frank, Sabrina N.; Singer, Christoph; Sures, Bernd

    2008-01-01

    The effects of different exposure concentrations of palladium (Pd) on relative metallothionein (MT) response and bioaccumulation were investigated in zebra mussels (Dreissena polymorpha). The mussels were exposed to 0.05, 5, 50, and 500 μg/L Pd 2+ for 10 weeks under controlled temperature and fasting conditions. Relative MT contents were assessed by a modified Ag-saturation method, which allows to discriminate between MT bound to Pd (Pd-MT) and MT bound to unidentified metals (Ag-MT). Determination of metal contents resulted from atomic absorption spectrometry following a microwave digestion. For unexposed mussels and mussels exposed to 0.05 μg/L Pd no metal accumulation could be detected. All other exposure concentrations resulted in detectable Pd accumulation in mussels with final tissue concentrations of 96 μg/g (500 μg/L), 45 μg/g (50 μg/L), and 9 μg/g (5 μg/L). Compared with initial levels Pd-MT concentrations at the end of the exposure period were 600 (500 μg/L), 160 (50 μg/L), and 27 (5 μg/L) times higher. These results show that an increase in MTs in D. polymorpha already occurs at relatively low aqueous Pd concentrations indicating that there is the need for detoxification of Pd in the mussel. Furthermore, correlations between Ag-MT and Pd accumulation indicate that higher exposure concentrations are associated with adverse effects on the mussels. Thus, harmful effects of chronic Pd exposure of organisms even in lowest concentrations cannot be excluded in the environment

  1. Transcriptional responses of metallothionein gene to different stress factors in Pacific abalone (Haliotis discus hannai).

    Science.gov (United States)

    Lee, Sang Yoon; Nam, Yoon Kwon

    2016-11-01

    A novel metallothionein (MT) gene from the Pacific abalone H. discus hannai was characterized and its mRNA expression patterns (tissue distribution, developmental expression and differential expression in responsive to various in vivo stimulatory treatments) were examined. Abalone MT shares conserved structural features with previously known gastropod orthologs at both genomic (i.e., tripartite organization) and amino acid (conserved Cys motifs) levels. The 5'-flanking regulatory region of abalone MT gene displayed various transcription factor binding motifs particularly including ones related with metal regulation and stress/immune responses. Tissue distribution and basal expression patterns of MT mRNAs indicated a potential association between ovarian MT expression and sexual maturation. Developmental expression pattern suggested the maternal contribution of MT mRNAs to embryonic and early larval developments. Abalone MT mRNAs could be significantly induced by various heavy metals in different tissues (gill, hepatopancreas, muscle and hemocyte) in a tissue- and/or metal-dependent fashion. In addition, the abalone MT gene was highly modulated in responsive to other non-metal, stimulatory treatments such as immune challenge (LPS, polyI:C and bacterial injections), hypoxia (decrease from normoxia 8 ppm-2 ppm), thermal elevation (increase from 20 °C to 30 °C), and xenobiotic exposure (250 ppb of 17α-ethynylestradiol and 0.25 ppb of 2,3,7,8-tetrachlorodibenzodioxin) where differential expression patterns were toward either up- or down-regulation depending on types of stimulations and tissues examined. Taken together, our results highlight that MT is a multifunctional effector playing in wide criteria of cellular pathways especially associated with development and stress responses in this abalone species. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Protection against UVA-induced photooxidative damage in mammalian cell lines expressing increased levels of metallothionein

    International Nuclear Information System (INIS)

    Dudek, E.J.; Roth, R.M.

    1990-01-01

    Metallothionein (MT) is an endogenous low molecular weight protein that is inducible in a variety of eukaryotic cells and has the ability to selectivity bind heavy metal ions such as zinc and the cadmium. Although the exact physiological role of MT is still not understood, there is strong evidence that MT is involved in providing cellular resistance against the damaging effects of heavy metals and in the regulation of intracellular zinc and copper. Recently, it has been demonstrated that MT can scavenge radiation-induced reactive oxygen intermediates in vitro, specifically hydroxyl and superoxide radicals, and because of these observations it has been suggested that MT may provide protection against radiation-induced oxidative stress in vivo. Cell lines expressing increased levels of MT have demonstrated resistance to ionizing radiation, to ultraviolet radiation, and also to various DNA damaging agents including melphalan and cis-diaminedichloroplatinum. It is therefore important to gain some insight into the relationship between cellular MT content and cellular resistance to radiation and other DNA damaging agents. In this study we investigated the role of MT in providing protection against monochromatic 365-nm UVA radiation, which is known to generate intracellular reactive oxygen species that are involved in both DNA damage and cell killing. For this purpose, we used zinc acetate, a potent inducer of MT, to elevate MT levels in V79 Chinese hamster fibroblasts prior to UVA exposure and determined cell survival for uninduced and induced cultures. In order to eliminate any zinc effects other than MT induction, we also isolated and characterized cadmium chloride-resistant clones of V79 cells that have increased steady-state levels of both MT mRNA and protein, and we examined their survival characteristics against 365-nm radiation in the absence of zinc acetate. 14 refs., 3 figs

  3. Effects of metallothionein on zinc metabolism in lethal-milk mutant mice

    Energy Technology Data Exchange (ETDEWEB)

    Grider, A. Jr.

    1986-01-01

    The lethal-milk mice (C57BL/6J-Im) exhibit various pleiotropic effects, including a congenital otolith defect, production of zinc-deficient milk, and clinical signs of a systemic Zn deficiency by one year of age. The clinical signs include alopecia, dermatitis, and skin lesions. The systemic zinc deficiency may be due to increased levels of metallothionein (MT) in the intestine and/or liver of Im mice. The untreated Im mice contain twice as much intestinal MT as do C57BL/6J-(+/sup im//+ /sup Im/) (B6) controls. This was determined by a sulfhydryl assay, by the /sup 109/Cd-saturation/hemolysate method, and by the /sup 65/Zn-binding assay. Various concentrations of Cd or Zn were added to the drinking water three days before assaying for MT. Compared to B6 mice, the Im mice exhibited more MT in their liver by the /sup 65/Zn-MT binding assay (3-fold) and by the /sup 109/Cd-saturation/hemolysate method (18-fold). The effects of the two zinc treatments did not differ significantly between Im and B6 mice. The retention and excretion of /sup 65/Zn (administered intraperitoneally) were determined over a 14-day period, but the results did not different between the Im and B6 mice. The increased concentrations of MT within the Im mice was not significantly different for the intestine and liver. Based on these data and other studies, the Im mice may exhibit alterations in zinc homeostasis due to some deregulation of MT metabolism, including the inner ear of the fetus, the lactating mammary gland, and the intestine and liver of adults by one year of age.

  4. METHAMPHETAMINE-INDUCED CELL DEATH: SELECTIVE VULNERABILITY IN NEURONAL SUBPOPULATIONS OF THE STRIATUM IN MICE

    Science.gov (United States)

    ZHU, J. P. Q.; XU, W.; ANGULO, J. A.

    2010-01-01

    Methamphetamine (METH) is an illicit and potent psychostimulant, which acts as an indirect dopamine agonist. In the striatum, METH has been shown to cause long lasting neurotoxic damage to dopaminergic nerve terminals and recently, the degeneration and death of striatal cells. The present study was undertaken to identify the type of striatal neurons that undergo apoptosis after METH. Male mice received a single high dose of METH (30 mg/kg, i.p.) and were killed 24 h later. To demonstrate that METH induces apoptosis in neurons, we combined terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) staining with immunohistofluorescence for the neuronal marker neuron-specific nuclear protein (NeuN). Staining for TUNEL and NeuN was colocalized throughout the striatum. METH induces apoptosis in approximately 25% of striatal neurons. Cell counts of TUNEL-positive neurons in the dorsomedial, ventromedial, dorsolateral and ventrolateral quadrants of the striatum did not reveal anatomical preference. The type of striatal neuron undergoing cell death was determined by combining TUNEL with immunohistofluorescence for selective markers of striatal neurons: dopamine- and cAMP-regulated phosphoprotein, of apparent Mr 32,000, parvalbumin, choline acetyltransferase and somatostatin (SST). METH induces apoptosis in approximately 21% of dopamine- and cAMP-regulated phosphoprotein, of apparent Mr 32,000-positive neurons (projection neurons), 45% of GABA-parvalbumin-positive neurons in the dorsal striatum, and 29% of cholinergic neurons in the dorsal–medial striatum. In contrast, the SST-positive interneurons were refractory to METH-induced apoptosis. Finally, the amount of cell loss determined with Nissl staining correlated with the amount of TUNEL staining in the striatum of METH-treated animals. In conclusion, some of the striatal projection neurons and the GABA-parvalbumin and cholinergic interneurons were removed by apoptosis in the aftermath of METH. This

  5. Specificity and divergence in the neurobiologic effects of different metallothioneins after brain injury

    DEFF Research Database (Denmark)

    Penkowa, Milena; Tio, Laura; Giralt, Mercedes

    2006-01-01

    isoform. Human rMT-III, in contrast to human nMT-IIa, did not affect inflammation, oxidative stress, and apoptosis, and showed opposite effects on several growth factors, neurotrophins, and markers of synaptic growth and plasticity. Our data thus highlight specific and divergent roles of exogenous MT...

  6. Coordinated responses of phytochelatin synthase and metallothionein genes in black mangrove, Avicennia germinans, exposed to cadmium and copper

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez-Mendoza, Daniel [Departamento de Recursos del Mar, Cinvestav-Unidad Merida, Merida, Yucatan (Mexico); Moreno, Adriana Quiroz [Unidad de biotecnologia, CICY, Merida, Yucatan (Mexico); Zapata-Perez, Omar [Departamento de Recursos del Mar, Cinvestav-Unidad Merida, Merida, Yucatan (Mexico)]. E-mail: ozapata@mda.cinvestav.mx

    2007-08-01

    To evaluate the role of phytochelatins and metallothioneins in heavy metal tolerance of black mangrove Avicennia germinans, 3-month-old seedlings were exposed to cadmium or copper for 30 h, under hydroponic conditions. Degenerate Mt2 and PCS primers were synthesized based on amino acid and nucleotide alignment sequences reported for Mt2 and PCS in other plant species found in GenBank. Total RNA was isolated from A. germinans leaves and two partial fragments of metallothionein and phytochelatin synthase genes were isolated. Gene expression was evaluated with reverse transcripatase-polymerase chain reaction (RT-PCR) amplification technique. Temporal analysis showed that low Cd{sup 2+} and Cu{sup 2+} concentrations caused a slight (but not significant) increase in AvMt2 expression after a 16 h exposure time, while AvPCS expression showed a significant increase under the same conditions but only after 4 h. Results strongly suggest that the rapid increase in AvPCS expression may contribute to Cd{sup 2+} and Cu{sup 2+} detoxification. Moreover, we found that A. germinans has the capacity to over-express both genes (AvMt2 and AvPCS), which may constitute a coordinated detoxification response mechanism targeting non-essential metals. Nonetheless, our results confirm that AvPCS was the most active gene involved in the regulation of essential metals (e.g., Cu{sup 2+}) in A. germinans leaves.

  7. An alternative interface for CE-ICP-MS cadmium speciation in metallothioneins based on volatile species generation

    International Nuclear Information System (INIS)

    Alvarez-Llamas, G.; Fernandez de la Campa, M.R.; Sanz-Medel, A.

    2005-01-01

    An alternative CE-ICP-MS interface based on volatile species generation (VSG) is here developed, evaluated and compared to the conventional sample introduction systems via nebulisation. For this purpose, the speciation of Cd-metallothioneins (MTs) in rabbit liver is taken as a model. Cd, bound to the different MT isoforms previously separated by CE, is transformed into volatile species at the exit of the capillary and on-line detected by ICP-MS. Optimum conditions for Cd VSG have been investigated in a flow injection device, using NaBH 4 as hydrogenation reagent in a HCl medium containing cobalt and thiourea as catalysts. Sample volume injected, CE separation voltage and reagents flows have been optimised. Analytical performance characteristics of the CE-VSG-ICP-(Q)MS coupling developed were evaluated, in terms of repeatability and linearity of response, using standard rabbit liver metallothionein isoforms (MT1 and MT2). Detection limits for Cd-MTs turned out to be almost one order of magnitude better than those derived from using a conventional Babington nebuliser-based interface. Compared to a MicroMist-based interface detection limits resulted to be similar, but the observed peak height was eight times higher using the VSG interface, indicating the enhanced analyte transport efficiency derived from VSG sample introduction systems

  8. Early-phase immunodetection of metallothionein and heat shock proteins in extruded earthworm coelomocytes after dermal exposure to metal ions

    International Nuclear Information System (INIS)

    Homa, Joanna; Olchawa, Ewa; Stuerzenbaum, Stephen R.; John Morgan, A.; Plytycz, Barbara

    2005-01-01

    This paper provides direct evidence that earthworm immune cells, coelomocytes, are exposed to bio-reactive quantities of metals within 3 days after dermal exposure, and that they respond by upregulating metallothionein (MT) and heat shock protein (HSP70, HSP72) expression. Indirect support for the hypothesis that coelomocytes are capable of trafficking metals was also obtained. Coelomocytes were expelled from adult individuals of Eisenia fetida after 3-day exposure either to metal ions (Zn, Cu, Pb, Cd) or to distilled water (controls) via filter papers. The number of coelomocytes was significantly decreased after Cu, Pb, or Cd treatment. Cytospin preparations of coelomocytes were subjected to immunoperoxidase staining with monoclonal antibodies against human heat shock proteins (HSP70 or HSP72), or rabbit polyclonal antibodies raised against metallothionein 2 (w-MT2) of Lumbricus rubellus. Applied antibodies detected the respective proteins of E. fetida and revealed that the expression of HSP70, HSP72 and w-MT2 proteins was either induced or significantly enhanced in coelomocytes from metal-exposed animals. In conclusion, stress protein expression in earthworm coelomocytes may be used as sensitive biomarkers of metal contaminations. Further experimentation is needed for quantitative analysis of kinetics of metal-induced stress protein expression in earthworm coelomocytes. - Metals upregulate stress response proteins in earthworm coelomocytes

  9. Survey of ABC transporter and metallothionein genes expressions in tall fescue inoculated with Funneliformis intraradices under Nickel toxicity

    Directory of Open Access Journals (Sweden)

    Massomeh Rafiei-Demneh

    2016-09-01

    Full Text Available In plants, there are complex network of transport, chelation, and sequestration processes that functions in maintaining concentrations of essential metal ions in different cellular compartments, thus minimizing the damage caused by entry of non-essential metal ions into the cytosol. In the presence of toxic ones, arbuscular mycorrhizal (AM fungi are able to alleviate metal toxicity in the plant. In this study the effect of an arbuscular mycorrhizal fungi Funneliformis intraradices on growth, Nickel tolerance, and ABC transporter and metallothionein expression in leaves and roots of tall fescue (Festuca arundinacea plants cultivated in Ni polluted soil were evaluated. The fungi infected (M+ and uninfected (M- fescue plants were cultivated in soil under different Ni concentrations (0, 30, 90 and 180 ppm for 3 months. Results demonstrated the positive effect of fungi colonization on the increase in growth and reduction in Ni uptake (90 and 180 ppm and Ni translocation from roots to shoot of tall fescue under Ni stress. The results also demonstrated that the level of ABC transporterand metallothionein transcripts accumulation in roots was considerably higher for both M- and M+ plants compared to the control. Also, M+ plants showed less ABC and MET expression compared to the M- plants. These results demonstrated the importance of mycorrhizal colonization of F. intraradices in reduction of Ni transport from root to shoot of tall fescue which alleviates Ni-induced stress.

  10. Overexpression of metallothionein in CHO cells and its effect on cell killing by ionizing radiation and alkylating agents

    International Nuclear Information System (INIS)

    Lohrer, H.; Robson, T.

    1989-01-01

    Metallothionein protein protects cells from the toxic effects of heavy metal ions. To establish its protective function against ionizing radiation and alkylating agents, a model system was created by transfecting two CHO cell lines (wild-type, K1-2 and X-ray sensitive, xrs-2 subclone Bc11) with the human metallothionein II-A (hMTII-A) gene integrated in a bovine papilloma derived autonomously replicating vector. The isolated transfectants are cadmium-resistant (Cd 1 ), due to the overexpression of the hMTII-A gene. Their steady-state level of hMTII-A mRNA can be increased up to 40-fold after Cd treatment and 20-fold after induction with ionizing radiation. The transfected cell lines proved to be as sensitive as the recipient cell lines to ionizing radiation and bleomycin but the transfectants were significantly more resistant to N-methyl-nitro-nitrosoguanidine (MNNG) and mitomycin C (MMC). These results lead to the conclusion that the MT protein does provide a defence mechanism to protect cells from monofunctional alkylating and cross-linking agents but not from free radicals. (author)

  11. Overexpression of metallothionein in CHO cells and its effect on cell killing by ionizing radiation and alkylating agents

    Energy Technology Data Exchange (ETDEWEB)

    Lohrer, H.; Robson, T. (Newcastle upon Tyne Univ. (UK). Cancer Research Unit)

    1989-12-01

    Metallothionein protein protects cells from the toxic effects of heavy metal ions. To establish its protective function against ionizing radiation and alkylating agents, a model system was created by transfecting two CHO cell lines (wild-type, K1-2 and X-ray sensitive, xrs-2 subclone Bc11) with the human metallothionein II-A (hMTII-A) gene integrated in a bovine papilloma derived autonomously replicating vector. The isolated transfectants are cadmium-resistant (Cd{sup 1}), due to the overexpression of the hMTII-A gene. Their steady-state level of hMTII-A mRNA can be increased up to 40-fold after Cd treatment and 20-fold after induction with ionizing radiation. The transfected cell lines proved to be as sensitive as the recipient cell lines to ionizing radiation and bleomycin but the transfectants were significantly more resistant to N-methyl-nitro-nitrosoguanidine (MNNG) and mitomycin C (MMC). These results lead to the conclusion that the MT protein does provide a defence mechanism to protect cells from monofunctional alkylating and cross-linking agents but not from free radicals. (author).

  12. Heavy metals in the fishery products of low Lazio and the use of metallothionein as a biomarker of contamination.

    Science.gov (United States)

    Papetti, P; Rossi, G

    2009-12-01

    This study aims to investigate the use of metallothionein as a biomarker and its environmental impact on aquatic systems. According to the species' characteristics, the interactions of toxic elements with living organisms in marine water can lead to biomagnifications in the trophic chain or bioconcentration of what is in the water. In many aquatic organisms, the presence of metallothionein proteins was studied. The chemical analysis of these bioindicators establishes, therefore, a sensitive method for the measurement of bioavailability which, over the years, allows for the quantification of the current pollution agents in the environment. Two study areas were selected along the Latium coasts. They are differentiated by their economic activities and their kind and level of environmental impact (mainly on marine pollution). These areas were selected in order to differentiate the maximum degree of both economic development and environmental quality. In particular, the presence of pollutants in the sea due to land activities was evaluated to compare the quality of the fishing products obtained from locations subject to various environmental impacts. The heavy metal concentrations were evaluated in water samples taken from different 30 sections of the fishes in order to understand the metabolism and origin of these contaminants. The primary metals studied were: mercury (Hg), zinc (Zn), nickel (Ni), lead (Pb), cadmium (Cd), and copper (Cu). All data produced were analyzed via multivariate analyses in order to provide a final and reliable indicator.

  13. Early-phase immunodetection of metallothionein and heat shock proteins in extruded earthworm coelomocytes after dermal exposure to metal ions

    Energy Technology Data Exchange (ETDEWEB)

    Homa, Joanna [Department of Evolutionary Immunobiology, Institute of Zoology, Jagiellonian University, R. Ingardena 6, PL 30-060 Cracow (Poland); Olchawa, Ewa [Department of Evolutionary Immunobiology, Institute of Zoology, Jagiellonian University, R. Ingardena 6, PL 30-060 Cracow (Poland); Stuerzenbaum, Stephen R. [Cardiff School of Biosciences, Cardiff University, PO Box 915, Cardiff Wales CF10 3TL (United Kingdom); John Morgan, A. [Cardiff School of Biosciences, Cardiff University, PO Box 915, Cardiff Wales CF10 3TL (United Kingdom); Plytycz, Barbara [Department of Evolutionary Immunobiology, Institute of Zoology, Jagiellonian University, R. Ingardena 6, PL 30-060 Cracow (Poland)]. E-mail: plyt@zuk.iz.uj.edu.pl

    2005-05-01

    This paper provides direct evidence that earthworm immune cells, coelomocytes, are exposed to bio-reactive quantities of metals within 3 days after dermal exposure, and that they respond by upregulating metallothionein (MT) and heat shock protein (HSP70, HSP72) expression. Indirect support for the hypothesis that coelomocytes are capable of trafficking metals was also obtained. Coelomocytes were expelled from adult individuals of Eisenia fetida after 3-day exposure either to metal ions (Zn, Cu, Pb, Cd) or to distilled water (controls) via filter papers. The number of coelomocytes was significantly decreased after Cu, Pb, or Cd treatment. Cytospin preparations of coelomocytes were subjected to immunoperoxidase staining with monoclonal antibodies against human heat shock proteins (HSP70 or HSP72), or rabbit polyclonal antibodies raised against metallothionein 2 (w-MT2) of Lumbricus rubellus. Applied antibodies detected the respective proteins of E. fetida and revealed that the expression of HSP70, HSP72 and w-MT2 proteins was either induced or significantly enhanced in coelomocytes from metal-exposed animals. In conclusion, stress protein expression in earthworm coelomocytes may be used as sensitive biomarkers of metal contaminations. Further experimentation is needed for quantitative analysis of kinetics of metal-induced stress protein expression in earthworm coelomocytes. - Metals upregulate stress response proteins in earthworm coelomocytes.

  14. Expression of metallothioneins I and II related to oxidative stress in the liver of aluminium-treated rats.

    Science.gov (United States)

    Ghorbel, Imen; Chaabane, Mariem; Elwej, Awatef; Boudawara, Ons; Abdelhedi, Sameh; Jamoussi, Kamel; Boudawara, Tahya; Zeghal, Najiba

    2016-10-01

    Hepatotoxicity, induced by aluminium chloride (AlCl 3 ), has been well studied but there are no reports about liver metallothionein (MT) genes induction. Therefore, it is of interest to establish the mechanism involving the relation between MT gene expression levels and the oxidative stress status in hepatic cells of aluminium-treated rats. Aluminium (Al) was administered to rats in their drinking water at a dose of 50 mg/kg body weight for three weeks. AlCl 3 provoked hepatotoxicity objectified by an increase in malondialdehyde (MDA), hydrogen peroxide (H 2 O 2 ), advanced oxidation protein products (AOPP), protein carbonyls (PCO) and a decrease in reduced glutathione (GSH), non-protein thiols (NPSH) and vitamin C. CAT and Glutathione peroxidase (GPx) activities were decreased while Mn-SOD gene expression, total Metallothionein content and MT I and MT II genes induction were increased. There are changes in plasma of some trace elements, albumin levels, transaminases, LDH and ALP activities. All these changes were supported by histopathological observations.

  15. Metallothionein induction, antioxidative responses, glycogen and growth changes in Tubifex tubifex (Oligochaete) exposed to the fungicide, fenhexamid

    International Nuclear Information System (INIS)

    Mosleh, Yahia Y.; Paris-Palacios, Severine; Couderchet, Michel; Biagianti-Risbourg, Sylvie; Vernet, Guy

    2005-01-01

    Laboratory studies were conducted to determine the effects of different concentrations of fenhexamid (0.1, 1, and 10 mg L -1 ) on growth, oxidative stress, protein, glycogen, and metallothionein (MT) contents in Tubifex tubifex after an exposure of 2, 4, and 7 days. In addition, residues of the fungicide were followed in water and in the worms. In water, fenhexamid concentration decreased slowly (maximum - 2±0.03% after 2 days for 1 mg L -1 ). In the worms, it increased after 4 days and decreased thereafter, confirming that the worms were exposed to the fungicide and not to a degradation product. LC 50 values were between 95.22±5.36 and 32.11±1.8 mg L -1 depending on exposure time. Exposure to fenhexamid had a negative effect on T. tubifex growth (maximum effect -12.2±0.8% after 7 days with 10 mg L -1 ) demonstrating the toxic effect of the pesticide. This growth rate decrease was accompanied by a reduction in protein and glycogen contents. The activity of catalase (CAT), and glutathione reductase (GR) increased in response to the fungicide demonstrating an oxidative stress in the worms. In contrast glutathion-S-transferase activity (GST) decreased. Exposure to fenhexamid also induced synthesis of MT (maximum +78±8% after 2 days for 10 mg L -1 ). The specificity of MT concentration increase in response to metals is discussed. - Exposure to the fungicide fenhexamid increased metallothionein levels in Tubifex tubifex

  16. Influence of Cadmium(II Ions and Brewery Sludge on Metallothionein Level in Earthworms (Eisenia fetida – Bio- transforming of Toxic Wastes

    Directory of Open Access Journals (Sweden)

    Rene Kizek

    2008-02-01

    Full Text Available Metallothioneins belong to a group of intracellular, high molecular andcysteine-rich proteins whose content in an organism increase with increasing concentrationof a heavy metal. The aim of this work was to apply the electrochemical analysis for theanalysis of metallothioneins in earthworms exposed to cadmium ions and brewery sludge.Here we utilized adsorptive transfer technique coupled with differential pulse voltammetryBrdicka reaction to determine metallothionein in different biological samples. By meansthis very sensitive technique it was possible to analyze metallothionein in concentrationsbelow 1 μmol.l-1 with the standard deviation of 4-5%. We found out that the average MTlevel in the non-treated earthworms oscillated between 19 and 48 μmol.l-1. When weanalysed samples of earthworms treated by cadmium, we observed that the MT contentincreased with the exposition length and increase dose of cadmium ions. Finally, weattempted to study and compare the toxicity of the raw sludge and its leach by using ofearthworms. The raw brewery sludge caused the death of the earthworms quickly.Earthworms held in the presence of leach from brewery sludge increased their weight of147 % of their original weight because they ingested the nutrients from the sludge. Themetallothionein level changes markedly with increasing time of exposition and applieddose of toxic compound. It clearly follows from the obtained results that the MT synthesisis insufficient in the first hours of the exposition and increases after more than 24 h.

  17. Metallothionein isoform 2A expression is inducible and protects against ROS-mediated cell death in rotenone-treated HeLa cells.

    NARCIS (Netherlands)

    Reinecke, F.; Levanets, O.; Olivier, Y.; Louw, R.; Semete, B.; Grobler, A.; Hidalgo, J.; Smeitink, J.A.M.; Olckers, A.; Westhuizen, F.H. van der

    2006-01-01

    The role of MT (metallothionein) gene expression was investigated in rotenone-treated HeLa cells to induce a deficiency of NADH:ubiquinone oxidoreductase (complex I). Complex I deficiency leads to a diversity of cellular consequences, including production of ROS (reactive oxygen species) and

  18. Evaluation of metallothionein formation as a proxy for zinc absorption in an in vitro digestion/caco-2 cell culture model

    Science.gov (United States)

    Caco-2 cell metallothionein (MT) formation was studied to determine if MT could be used as a proxy for zinc (Zn) absorption in a cell culture model. MT intracellular concentration was determined by using a cadmium/hemoglobin affinity assay. Cellular Zn uptake was determined in acid digests (5% HNO3)...

  19. Reassessing apoptosis in plants.

    Science.gov (United States)

    Dickman, Martin; Williams, Brett; Li, Yurong; de Figueiredo, Paul; Wolpert, Thomas

    2017-10-01

    Cell death can be driven by a genetically programmed signalling pathway known as programmed cell death (PCD). In plants, PCD occurs during development as well as in response to environmental and biotic stimuli. Our understanding of PCD regulation in plants has advanced significantly over the past two decades; however, the molecular machinery responsible for driving the system remains elusive. Thus, whether conserved PCD regulatory mechanisms include plant apoptosis remains enigmatic. Animal apoptotic regulators, including Bcl-2 family members, have not been identified in plants but expression of such regulators can trigger or suppress plant PCD. Moreover, plants exhibit nearly all of the biochemical and morphological features of apoptosis. One difference between plant and animal PCD is the absence of phagocytosis in plants. Evidence is emerging that the vacuole may be key to removal of unwanted plant cells, and may carry out functions that are analogous to animal phagocytosis. Here, we provide context for the argument that apoptotic-like cell death occurs in plants.

  20. Bax regulates neuronal Ca2+ homeostasis.

    Science.gov (United States)

    D'Orsi, Beatrice; Kilbride, Seán M; Chen, Gang; Perez Alvarez, Sergio; Bonner, Helena P; Pfeiffer, Shona; Plesnila, Nikolaus; Engel, Tobias; Henshall, David C; Düssmann, Heiko; Prehn, Jochen H M

    2015-01-28

    Excessive Ca(2+) entry during glutamate receptor overactivation ("excitotoxicity") induces acute or delayed neuronal death. We report here that deficiency in bax exerted broad neuroprotection against excitotoxic injury and oxygen/glucose deprivation in mouse neocortical neuron cultures and reduced infarct size, necrotic injury, and cerebral edema formation after middle cerebral artery occlusion in mice. Neuronal Ca(2+) and mitochondrial membrane potential (Δψm) analysis during excitotoxic injury revealed that bax-deficient neurons showed significantly reduced Ca(2+) transients during the NMDA excitation period and did not exhibit the deregulation of Δψm that was observed in their wild-type (WT) counterparts. Reintroduction of bax or a bax mutant incapable of proapoptotic oligomerization equally restored neuronal Ca(2+) dynamics during NMDA excitation, suggesting that Bax controlled Ca(2+) signaling independently of its role in apoptosis execution. Quantitative confocal imaging of intracellular ATP or mitochondrial Ca(2+) levels using FRET-based sensors indicated that the effects of bax deficiency on Ca(2+) handling were not due to enhanced cellular bioenergetics or increased Ca(2+) uptake into mitochondria. We also observed that mitochondria isolated from WT or bax-deficient cells similarly underwent Ca(2+)-induced permeability transition. However, when Ca(2+) uptake into the sarco/endoplasmic reticulum was blocked with the Ca(2+)-ATPase inhibitor thapsigargin, bax-deficient neurons showed strongly elevated cytosolic Ca(2+) levels during NMDA excitation, suggesting that the ability of Bax to support dynamic ER Ca(2+) handling is critical for cell death signaling during periods of neuronal overexcitation. Copyright © 2015 the authors 0270-6474/15/351706-17$15.00/0.

  1. Role of Notch-1 signaling in ethanol induced PC12 apoptosis | Li ...

    African Journals Online (AJOL)

    Chronic alcoholic dementia has crucial role in progress of neurodegenerative disease and affects a large portion of our aging population. Neuronal cell apoptosis may be a contributing factor of neurodegenerative disease (ND) and Alzheimer's disease (AD). Previous researches have indicated that Notch-1 signaling ...

  2. Partial contribution of the Keap1–Nrf2 system to cadmium-mediated metallothionein expression in vascular endothelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Shinkai, Yasuhiro [Environmental Biology Laboratory, Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8575 (Japan); Kimura, Tomoki [Faculty of Science and Engineering, Setsunan University, 17-8 Ikedanaka-machi, Neyagawa, Osaka 572-8508 (Japan); Itagaki, Ayaka [Faculty of Pharmaceutical Sciences, Hokuriku University, Ho-3 Kanagawa, Kanazawa, 920-1181, Ishikawa (Japan); Yamamoto, Chika [Faculty of Pharmaceutical Sciences, Hokuriku University, Ho-3 Kanagawa, Kanazawa, 920-1181, Ishikawa (Japan); Faculty of Pharmaceutical Sciences, Toho University, 2-2-1 Miyama, Funabashi, Chiba 274-8510 (Japan); Taguchi, Keiko; Yamamoto, Masayuki [Department of Medical Biochemistry, Tohoku University Graduate School of Medicine, 2-1 Seiryo-cho, Aoba-ku, Sendai 980-8575 (Japan); Kumagai, Yoshito, E-mail: yk-em-tu@md.tsukuba.ac.jp [Environmental Biology Laboratory, Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8575 (Japan); Kaji, Toshiyuki, E-mail: t-kaji@rs.tus.ac.jp [Faculty of Pharmaceutical Sciences, Hokuriku University, Ho-3 Kanagawa, Kanazawa, 920-1181, Ishikawa (Japan); Faculty of Pharmaceutical Sciences, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba 278-8510 (Japan)

    2016-03-15

    Cadmium is an environmental electrophile that modifies protein reactive thiols such as Kelch-like ECH-associated protein 1 (Keap1), a negative regulator of nuclear factor-erythroid 2-related factor 2 (Nrf2). In the present study, we investigated a role of the Keap1–Nrf2 system in cellular response to cadmium in vascular endothelial cells. Exposure of bovine aortic endothelial cells to cadmium resulted in modification of Keap1 and Nrf2 activation, thereby up-regulating not only its typical downstream proteins but also metallothionein-1/2. Experiments with siRNA-mediated knockdown of Nrf2 or Keap1 supported participation of the Keap1–Nrf2 system in the modulation of metallothionein-1/2 expression. Furthermore, chromatin immunoprecipitation assay showed that Nrf2 was recruited to the antioxidant response element of the promoter region of the bovine metallothionein-2 gene in the presence of cadmium. These results suggest that the transcription factor Nrf2 plays, at least in part, a role in the changes in metallothionein expression mediated by exposure to cadmium. - Highlights: • Role of the Keap1–Nrf2 system in cellular response to cadmium was examined. • We used bovine aortic endothelial cells as a model of the vascular endothelium. • Exposure of cells to cadmium resulted in modification of Keap1 and Nrf2 activation. • Keap1–Nrf2 system participated in the modulation of metallothionein-1/2 expression. • Nrf2 was recruited to the antioxidant response element of MT2 promoter region.

  3. Cardiovascular molecular imaging of apoptosis

    International Nuclear Information System (INIS)

    Wolters, S.L.; Reutelingsperger, C.P.M.; Corsten, M.F.; Hofstra, L.; Narula, J.

    2007-01-01

    Molecular imaging strives to visualise processes at the molecular and cellular level in vivo. Understanding these processes supports diagnosis and evaluation of therapeutic efficacy on an individual basis and thereby makes personalised medicine possible. Apoptosis is a well-organised mode of cell suicide that plays a role in cardiovascular diseases (CVD). Apoptosis is associated with loss of cardiomyocytes following myocardial infarction, atherosclerotic plaque instability, congestive heart failure and allograft rejection of the transplanted heart. Thus, apoptosis constitutes an attractive target for molecular imaging of CVD. Our current knowledge about the molecular players and mechanisms underlying apoptosis offers a rich palette of potential molecular targets for molecular imaging. However, only a few have been successfully developed so far. This review highlights aspects of the molecular machinery and biochemistry of apoptosis relevant to the development of molecular imaging probes. It surveys the role of apoptosis in four major areas of CVD and portrays the importance and future perspectives of apoptosis imaging. The annexin A5 imaging protocol is emphasised since it is the most advanced protocol to measure apoptosis in both preclinical and clinical studies. (orig.)

  4. Cardiovascular molecular imaging of apoptosis

    Energy Technology Data Exchange (ETDEWEB)

    Wolters, S.L.; Reutelingsperger, C.P.M. [Maastricht University, Department of Biochemistry, Cardiovascular Research Institute Maastricht, Maastricht (Netherlands); Corsten, M.F.; Hofstra, L. [Maastricht University, Department of Cardiology, Cardiovascular Research Institute Maastricht, P.O. Box 616, Maastricht (Netherlands); Narula, J. [University of California Irvine, Department of Cardiology, Irvine (United States)

    2007-06-15

    Molecular imaging strives to visualise processes at the molecular and cellular level in vivo. Understanding these processes supports diagnosis and evaluation of therapeutic efficacy on an individual basis and thereby makes personalised medicine possible. Apoptosis is a well-organised mode of cell suicide that plays a role in cardiovascular diseases (CVD). Apoptosis is associated with loss of cardiomyocytes following myocardial infarction, atherosclerotic plaque instability, congestive heart failure and allograft rejection of the transplanted heart. Thus, apoptosis constitutes an attractive target for molecular imaging of CVD. Our current knowledge about the molecular players and mechanisms underlying apoptosis offers a rich palette of potential molecular targets for molecular imaging. However, only a few have been successfully developed so far. This review highlights aspects of the molecular machinery and biochemistry of apoptosis relevant to the development of molecular imaging probes. It surveys the role of apoptosis in four major areas of CVD and portrays the importance and future perspectives of apoptosis imaging. The annexin A5 imaging protocol is emphasised since it is the most advanced protocol to measure apoptosis in both preclinical and clinical studies. (orig.)

  5. Lateral intracerebroventricular injection of Apelin-13 inhibits apoptosis after cerebral ischemia/reperfusion injury

    Directory of Open Access Journals (Sweden)

    Xiao-ge Yan

    2015-01-01

    Full Text Available Apelin-13 inhibits neuronal apoptosis caused by hydrogen peroxide, yet apoptosis following cerebral ischemia-reperfusion injury has rarely been studied. In this study, Apelin-13 (0.1 µg/g was injected into the lateral ventricle of middle cerebral artery occlusion model rats. TTC, TUNEL, and immunohistochemical staining showed that compared with the cerebral ischemia/reperfusion group, infarct volume and apoptotic cell number at the ischemic penumbra region were decreased in the Apelin-13 treatment group. Additionally, Apelin-13 treatment increased Bcl-2 immunoreactivity and decreased caspase-3 immunoreactivity. Our findings suggest that Apelin-13 is neuroprotective against cerebral ischemia/reperfusion injury through inhibition of neuronal apoptosis.

  6. The effects of air pollution and smoking on placental cadmium, zinc concentration and metallothionein expression

    International Nuclear Information System (INIS)

    Sorkun, Hulya Cetin; Bir, Ferda; Akbulut, Metin; Divrikli, Umit; Erken, Gulten; Demirhan, Huriye; Duzcan, Ender; Elci, Latif; Celik, Ismail; Yozgatli, Unsal

    2007-01-01

    This study is designed to determine the placental zinc (Zn) and cadmium (Cd) levels in mothers who were smokers, mothers who were thought to be exposed to air pollution, and mothers who were non-smokers and to investigate the relationship between the expression of placental metallothionein (MT) binding these metals and blood progesterone level. Placental Zn and Cd levels were measured by atomic absorption spectrometry. Presence of placental MT was determined immunohistochemically. Placental changes were examined by light microscope after H and E and PAS staining. Immunohistochemical MT staining of syncytiotrophoblastic and villous interstitial cells were scored as positive or negative. Among the 92 mothers included in the study, 33 were smokers (Group I), 29 had been exposed to air pollution (Group II) and 30 were non-smoker rural residents who had never been exposed to air pollution (Group III). Mean off-spring birth weight of 3198.62 ± 380.01 g and mean placenta weight of 561.38 ± 111.55 g of Group II were lower when compared with those of other two groups. In Group I, mean placental Cd and Zn were 0.063 ± 0.022 μg/g and 39.84 ± 15.5 μg/g, respectively, being higher than in other groups. In Group II, mean placental Cd and Zn levels were higher than those of Group III. Blood progesterone levels of subjects in Group I (121 ng/ml) were the lowest of all groups. While the mean count of villi was the highest in Group III; the highest mean count of syncytial knots was in Group II. Thickening of vasculo-syncytial membrane was most prominent in Group I. Similarly, MT staining was positive and very dense in 72.7% (24/33) of cases in Group I (p ≤ 0.05). MT staining was positive in 69.0% (29/20) and denser in Group II cases compared to 36% (11/30) in Group III (p ≤ 0.05). This study showed that smoking increased Cd levels in placenta and accompanied an increase in placental MT expression immunohistochemically. The effects of exposure to air pollution are equally

  7. Expression and function analysis of metallothionein in the testis of Portunus trituberculatus exposed to cadmium

    International Nuclear Information System (INIS)

    Xiang, Dong-Fang; Zhu, Jun-Quan; Jin, Shan; Hu, Yan-Jun; Tan, Fu-Qing; Yang, Wan-Xi

    2013-01-01

    Highlights: •We identified P. trituberculatus MT-1 and MT-2 complete cDNA sequence. •We analyzed the protein alignment comparisons and phylogenetic trees of MT-1 and MT-2. •RT-PCR analysis the tissue expression of MT-1 and MT-2 mRNA. •The spatial and temporal distribution pattern of MT-1 and MT-2 mRNA during spermiogenesis. •Testis MT-1 and MT-2 mRNA expression are dramatically affected after the cadmium exposure. -- Abstract: Metallothioneins (MTs) possess a unique molecular structure that provides metal-binding and redox capabilities. These capabilities include the maintenance of metal equilibria that protect against heavy metals (especially cadmium) and oxidative damage. Past studies have focused on the function of MTs in vertebrates. However, the functions of MTs during spermiogenesis in invertebrates remain unclear. In order to investigate the function of MTs during spermiogenesis in Portunus trituberculatus, we used RT-PCR and RACE to identify two MT complete cDNA sequences in the total RNA from the P. trituberculatus testis. The 450 bp MT-1 cDNA consists of a 77 bp 5′ untranslated region, a 196 bp 3′ untranslated region, and a 177 bp open reading frame that encodes 58 amino acids including 19 cysteines. The 581 bp MT-2 cDNA consists of 73 bp 5′ untranslated region, a 328 bp 3′ untranslated region, and a 180 bp open reading frame that encodes 59 amino acids including 18 cysteines. MT-1 and MT-2 of P. trituberculatus more closely resemble invertebrate (especially crab) MT homologues than vertebrate MT homologues as indicated by protein alignment comparisons and phylogenetic tree analysis. MT-1 and MT-2 were detected in the heart, testis, muscle, hepatopancreas, and gill of P. trituberculatus by tissue expression analysis. In addition, MT-1 and MT-2 are present during the entire process of spermiogenesis in P. trituberculatus as indicated by H and E staining and in situ hybridization. MT-1 and MT-2 expression levels significantly increase

  8. Expression and function analysis of metallothionein in the testis of Portunus trituberculatus exposed to cadmium

    Energy Technology Data Exchange (ETDEWEB)

    Xiang, Dong-Fang [School of Marine Sciences, Ningbo University, Ningbo, Zhejiang 315211 (China); The Sperm Laboratory, College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang 310058 (China); Zhu, Jun-Quan; Jin, Shan [School of Marine Sciences, Ningbo University, Ningbo, Zhejiang 315211 (China); Hu, Yan-Jun [Department of Reproductive Endocrinology, Women' s Hospital, School of Medicine, Zhejiang University, Hangzhou 310006 (China); Tan, Fu-Qing [The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou 310003 (China); Yang, Wan-Xi, E-mail: wxyang@spermlab.org [The Sperm Laboratory, College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang 310058 (China)

    2013-09-15

    Highlights: •We identified P. trituberculatus MT-1 and MT-2 complete cDNA sequence. •We analyzed the protein alignment comparisons and phylogenetic trees of MT-1 and MT-2. •RT-PCR analysis the tissue expression of MT-1 and MT-2 mRNA. •The spatial and temporal distribution pattern of MT-1 and MT-2 mRNA during spermiogenesis. •Testis MT-1 and MT-2 mRNA expression are dramatically affected after the cadmium exposure. -- Abstract: Metallothioneins (MTs) possess a unique molecular structure that provides metal-binding and redox capabilities. These capabilities include the maintenance of metal equilibria that protect against heavy metals (especially cadmium) and oxidative damage. Past studies have focused on the function of MTs in vertebrates. However, the functions of MTs during spermiogenesis in invertebrates remain unclear. In order to investigate the function of MTs during spermiogenesis in Portunus trituberculatus, we used RT-PCR and RACE to identify two MT complete cDNA sequences in the total RNA from the P. trituberculatus testis. The 450 bp MT-1 cDNA consists of a 77 bp 5′ untranslated region, a 196 bp 3′ untranslated region, and a 177 bp open reading frame that encodes 58 amino acids including 19 cysteines. The 581 bp MT-2 cDNA consists of 73 bp 5′ untranslated region, a 328 bp 3′ untranslated region, and a 180 bp open reading frame that encodes 59 amino acids including 18 cysteines. MT-1 and MT-2 of P. trituberculatus more closely resemble invertebrate (especially crab) MT homologues than vertebrate MT homologues as indicated by protein alignment comparisons and phylogenetic tree analysis. MT-1 and MT-2 were detected in the heart, testis, muscle, hepatopancreas, and gill of P. trituberculatus by tissue expression analysis. In addition, MT-1 and MT-2 are present during the entire process of spermiogenesis in P. trituberculatus as indicated by H and E staining and in situ hybridization. MT-1 and MT-2 expression levels significantly increase

  9. Structure and function of the human metallothionein gene family: Final technical report

    International Nuclear Information System (INIS)

    Karin, M.

    1986-01-01

    The full nucleotide sequence of two additional human metallothionein (hMT) genes has been determined. These genes, hMT-I/sub B/ and hMT-I/sub F/, are located within the MT-I gene cluster we have described originally. The hMT-I/sub F/ gene is the first hMT-I gene whose amino acid sequence is in complete agreement with the published sequence of the human MT-I proteins. Therefore it is likely to be an active gene encoding a functional protein. However, since we have just completed the sequence analysis, we have not characterized this gene further yet. The hMT-I/sub B/ gene is closely linked to the hMT-I/sub A/ gene, and two pseudogenes, hMT-I/sub C/ and hMT-I/sub D/ separate the two. From its nucleotide sequence hMT-I/sub B/ seems to be an active gene, encoding a functional protein even though it differs in four positions from the published sequence of human MT-I proteins. This gene is expressed in a human hepatoma cell line, HepG2, and its expression is stimulated by Cd ++ . Using gene fusions to the viral thymidine-kinase gene we find that hMT-I/sub B/, like the hMT-I/sub A/ and hMT-II/sub A/ genes, contains a heavy metal responsive promoterregulatory element within its 5' flanking region. We analyzed the level of hMT-I/sub B/ mRNA in a variety of human cell lines by the S1 nuclease technique, and compared it to the expression of the hMT-II/sub A/ gene. While the hMT-II/sub A/ gene was expressed in all of the cell lines analyzed, the hMT-I/sub B/ gene was expressed in liver and kidney derived cell lines cells. This suggest that the expression of the hMT-I/sub B/ gene is controlled in a tissue specific manner. 13 refs

  10. Location-specific epigenetic regulation of the metallothionein 3 gene in esophageal adenocarcinomas.

    Directory of Open Access Journals (Sweden)

    Dunfa Peng

    Full Text Available Metallothionein 3 (MT3 maintains intracellular metal homeostasis and protects against reactive oxygen species (ROS-induced DNA damage. In this study, we investigated the epigenetic alterations and gene expression of the MT3 gene in esophageal adenocarcinomas (EACs.Using quantitative bisulfite pyrosequencing, we detected unique DNA methylation profiles in the MT3 promoter region. The CpG nucleotides from -372 to -306 from the transcription start site (TSS were highly methylated in tumor (n = 64 and normal samples (n = 51, whereas CpG nucleotides closest to the TSS (-4 and +3 remained unmethylated in all normal and most tumor samples. Conversely, CpG nucleotides in two regions (from -139 to -49 and +296 to +344 were significantly hypermethylated in EACs as compared to normal samples [FDR3.0]. The DNA methylation levels from -127 to -8 CpG sites showed the strongest correlation with MT3 gene expression (r = -0.4, P<0.0001. Moreover, the DNA hypermethylation from -127 to -8 CpG sites significantly correlated with advanced tumor stages and lymph node metastasis (P = 0.005 and P = 0.0313, respectively. The ChIP analysis demonstrated a more repressive histone modification (H3K9me2 and less active histone modifications (H3K4me2, H3K9ace in OE33 cells than in FLO-1 cells; concordant with the presence of higher DNA methylation levels and silencing of MT3 expression in OE33 as compared to FLO-1 cells. Treatment of OE33 cells with 5-Aza-deoxycitidine restored MT3 expression with demethylation of its promoter region and reversal of the histone modifications towards active histone marks.In summary, EACs are characterized by frequent epigenetic silencing of MT3. The choice of specific regions in the CpG island is a critical step in determining the functional role and prognostic value of DNA methylation in cancer cells.

  11. Concentration of metallothionein in mice livers after a small dose of irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Saitou, Mikio; Yanai, Takanori; Hasegawa, Hidenao; Otsu, Hiroshi; Sato, Fumiaki [Inst. for Environmental Sciences, Rokkasho, Aomori (Japan); Akata, Naofumi; Kanaiwa-Kudo, Shouko; Matsumoto, Tsuneya; Noda, Yuko

    1998-12-01

    This study was made to determine whether metallothionein (MT) is induced by a small dose (0.5 Gy) irradiation. One hundred B6C3F1/Nrs mice of each sex, 8-10 weeks old, were used in the sham study (unirradiated controls) and experimental (irradiated) groups. Eighty mice of each sex were given acute whole body irradiation with {sup 197}Cs{gamma}-rays under SPF conditions; two doses of 0.5 and 5.0 Gy at 30 cm distance from the source at the rate of 0.563 Gy/min. Twenty mice of each sex were used in the sham study. Every ten male and female mouse was killed by cervical dislocation on days 1, 7, 14 and 21 after irradiation. The same numbers of male and female control mice were killed on days 0 and 21. Livers were removed immediately after death, and concentration of MT was examined. In both the males and females, the MT concentration of the 5 Gy-group peaked on the first day after irradiation, and there was no difference in comparison with the control values between the 7th and 21st days. In contrast, on no day did the MT concentration for the 0.5 Gy-group showed a significant difference from the control group. The time dependency patterns of the female and male mice also showed no significant differences for 5 Gy- and 0.5 Gy-groups, but the mean values of the MT concentration was lower in the males than in the females on the 1st day. Results of the direct quantitation of MT by the enzyme-linked immunoabsorbent assay (ELISA) also showed peak MT accumulation on the 1st day for both male and female mice. These were also shown by the atomic absorption spectrometry (AAS) and the inductively coupled plasma mass spectrometry (ICP-MS) analyses. But peak heights for the males and females showed a tendency inverse to that of the AAS and ICP-MS analyses. This discrepancy is attributable to the technical problem encountered in the experiment. On the basis of our findings, MT does not seem to be related to acquired radioresistance in mice. (K.H.)

  12. Effects of organism preparation in metallothionein and metal analysis in marine invertebrates for biomonitoring marine pollution.

    Science.gov (United States)

    Oaten, J F P; Hudson, M D; Jensen, A C; Williams, I D

    2015-06-15

    Metallothionein (MT) is established as a potentially useful biomarker for monitoring aquatic pollution. This paper addresses widespread inconsistencies in storage conditions, tissue type selection and pre-treatment of samples before MT and metal analysis in biomarker studies. This variation hampers comparability and so the widespread implementation of this monitoring approach. Actively sampled Mytilus edulis in Southampton Water, UK were exposed to different storage temperatures, a variety of tissue types were analysed, and various pre-treatments of transportation on ice, transportation in seawater, depuration, and rapid dissection in the field were examined. Storage temperatures of -20 °C were found to be adequate for periods of at least ten weeks, as MT was not reduced by protein degradation compared with samples kept at -80 °C. Whole tissue and digestive gland concentrations of MT and metals were significantly positively correlated and directly relatable. MT in the digestive gland appeared to be more responsive to metals than in whole tissue, where it may be diluted, masking MT responses. However, longer study periods may suffer the effects of mass changes to the digestive gland, which alters MT concentration, and it may therefore be advisable to measure whole tissue. Depuration and transportation in seawater reduced both MT and metal concentrations in the digestive gland, and few correlations between MT and metals were identified for these treatments. It is therefore recommended that: i) samples are transported to the laboratory on ice and dissected as soon as possible thereafter, ii) depuration should not be used when examining MT response to metal exposure until further research clarifying its utility is reported, iii) either whole tissue or the digestive gland can be used to measure MT, though whole tissue may be preferable on long-term studies, and iv) organisms can be stored at -20 °C before analysis for up to ten weeks. These practices can be applied

  13. Neuronal Migration Disorders

    Science.gov (United States)

    ... Understanding Sleep The Life and Death of a Neuron Genes At Work In The Brain Order Publications ... birth defects caused by the abnormal migration of neurons in the developing brain and nervous system. In ...

  14. Motor Neuron Diseases

    Science.gov (United States)

    ... and other neurodegenerative diseases to better understand the function of neurons and other support cells and identify candidate therapeutic ... and other neurodegenerative diseases to better understand the function of neurons and other support cells and identify candidate therapeutic ...

  15. Response of the common cutworm Spodoptera litura to zinc stress: Zn accumulation, metallothionein and cell ultrastructure of the midgut

    International Nuclear Information System (INIS)

    Shu, Yinghua; Zhang, Guren; Wang, Jianwu

    2012-01-01

    By exposing the common cutworm Spodoptera litura Fabricius larvae to a range of Zinc (Zn) stress, we investigated the effects of dietary Zn on Zn accumulation, metallothionein (MT), and on the ultrastructure of the midgut. The techniques we used were inductively coupled plasma-atomic emission spectrometer (ICP-AES), real-time PCR combined with cadmium-hemoglobin total saturation, and transmission electron microscopy (TEM), respectively. There was a significant dose–response relationship between the Zn accumulations in the midgut of the larvae and the Zn concentrations in the diet. Furthermore, both MT content and MT gene expression in the midgut were significantly induced in the 50–500 mg Zn/kg treatments, and were significantly positively correlated with the Zn accumulations in the midgut. When S. litura larvae were fed with the diet treated with 500 mg Zn/kg, Zn accumulation and MT content in the midgut was 4450.85 mg Zn/kg and 372.77 mg/kg, respectively, thereafter there was a little increase; the level of MT gene expression was maximal, thereafter there was a sharp decrease. TEM showed that numerous electron-dense granules (EDGs) and vacuoles appeared in the cytoplasm of the midgut cells, their number and size being closely correlated with the Zn accumulations in the midgut. Moreover, the nuclei were strongly influenced by Zn stress, evidenced by chromatin condensation and irregular nuclear membranes. Therefore, after being exposed to Zn in the threshold (500 mg Zn/kg) range, S. litura larvae could accumulate Zn in the midgut, which led to the induction of MT and changes in cell ultrastructure (mainly the presence of EDGs). The induction of MT and precipitation of Zn in EDGs may be the effective detoxification mechanisms by which the herbivorous insect S. litura defends itself against heavy metals. -- Graphical abstract: When the herbivorous insect Spodoptera litura Fabricius larvae were fed on the artificial diet with different concentrations of Zn

  16. Insight on trace element detoxification in the Black-tailed Godwit (Limosa limosa) through genetic, enzymatic and metallothionein analyses

    International Nuclear Information System (INIS)

    Lucia, Magali; Bocher, Pierrick; Cosson, Richard P.; Churlaud, Carine; Robin, Frédéric; Bustamante, Paco

    2012-01-01

    Trace element concentrations (Ag, As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Se, Zn) were investigated in the liver, kidneys, muscle and feathers of 31 black-tailed godwits (Limosa limosa) accidentally killed during catches by mist net in the Pertuis Charentais, Atlantic coast of France. Analyses of carbon and nitrogen stable isotope ratios were carried out in liver, muscle and feathers in order to elucidate dietary patterns and to determine whether differences in diet explained the variation in elemental uptake. This study also aimed to have a preliminary assessment of sub-lethal effects triggered by trace elements through the investigation of gene expressions by quantitative real-time PCR, antioxidant enzyme activities (catalase, superoxide dismutase, glutathione peroxidase), and metallothionein (MT) levels. The results showed that Cr and Ni concentrations in tissues of adults were lower than in juveniles in part because adults may have eliminated these trace elements through moulting. Except for Cd and Ni, trace element concentrations were negatively correlated to the body mass of godwits. Ag, As, Hg and Se concentrations were positively linked with the trophic position of birds. The diet could be considered as a fundamental route of exposure for these elements demonstrating therefore the qualitative linkage between dietary habits of godwits and their contaminant concentrations. Our results strongly suggest that even though trace element concentrations were mostly below toxicity threshold level, the elevated concentrations of As, Ag, Cd, Cu, Fe and Se may however trigger sub-lethal effects. Trace elements appear to enhance expression of genes involved in oxidative stress defence, which indicates the production of reactive oxygen species. Moreover, birds with the highest concentrations appeared to have an increased mitochondrial metabolism suggesting that the fight against trace element toxicity requires additional energetic needs notably to produce detoxification

  17. Insight on trace element detoxification in the Black-tailed Godwit (Limosa limosa) through genetic, enzymatic and metallothionein analyses

    Energy Technology Data Exchange (ETDEWEB)

    Lucia, Magali, E-mail: m.lucia33@laposte.net [Littoral, Environnement et Societes (LIENSs), UMR 7266 CNRS-Universite de La Rochelle, 2 rue Olympe de Gouges, 17000 La Rochelle (France); Bocher, Pierrick [Littoral, Environnement et Societes (LIENSs), UMR 7266 CNRS-Universite de La Rochelle, 2 rue Olympe de Gouges, 17000 La Rochelle (France); Cosson, Richard P. [Mer Molecules Sante (MMS), Universite de Nantes, EA 2663, 2 rue de la Houssiniere, BP 92208, 44322 Nantes Cedex 3 (France); Churlaud, Carine; Robin, Frederic; Bustamante, Paco [Littoral, Environnement et Societes (LIENSs), UMR 7266 CNRS-Universite de La Rochelle, 2 rue Olympe de Gouges, 17000 La Rochelle (France)

    2012-04-15

    Trace element concentrations (Ag, As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Se, Zn) were investigated in the liver, kidneys, muscle and feathers of 31 black-tailed godwits (Limosa limosa) accidentally killed during catches by mist net in the Pertuis Charentais, Atlantic coast of France. Analyses of carbon and nitrogen stable isotope ratios were carried out in liver, muscle and feathers in order to elucidate dietary patterns and to determine whether differences in diet explained the variation in elemental uptake. This study also aimed to have a preliminary assessment of sub-lethal effects triggered by trace elements through the investigation of gene expressions by quantitative real-time PCR, antioxidant enzyme activities (catalase, superoxide dismutase, glutathione peroxidase), and metallothionein (MT) levels. The results showed that Cr and Ni concentrations in tissues of adults were lower than in juveniles in part because adults may have eliminated these trace elements through moulting. Except for Cd and Ni, trace element concentrations were negatively correlated to the body mass of godwits. Ag, As, Hg and Se concentrations were positively linked with the trophic position of birds. The diet could be considered as a fundamental route of exposure for these elements demonstrating therefore the qualitative linkage between dietary habits of godwits and their contaminant concentrations. Our results strongly suggest that even though trace element concentrations were mostly below toxicity threshold level, the elevated concentrations of As, Ag, Cd, Cu, Fe and Se may however trigger sub-lethal effects. Trace elements appear to enhance expression of genes involved in oxidative stress defence, which indicates the production of reactive oxygen species. Moreover, birds with the highest concentrations appeared to have an increased mitochondrial metabolism suggesting that the fight against trace element toxicity requires additional energetic needs notably to produce detoxification

  18. Prenatal irradiation: radioinduced apoptosis in developing central nervous system

    International Nuclear Information System (INIS)

    Gisone, P.; Dubner, D.; Michelin, S.; Perez, M.R.; Barboza, M.

    1998-01-01

    Severe mental retardation (SMR) is the most significant effect of prenatal irradiation. The high radiosensitivity of developing brain is related with the chronology of morpho genetic phenomena regarding neuroblast proliferation, neuronal differentiation and migration, synaptogenesis and dendritic arborization. Programmed cell death (apoptosis) normally occurs during development in central nervous system (CNS). Apoptosis is a direct result of the expression of specific genes with a final common pathway leading to a characteristic DNA fragmentation pattern. A wide variety of situations and toxic agents have been reported to result in apoptotic death in developing CNS. The aim of this work was the characterization and quantification of apoptosis using an in vitro model of prenatal irradiation. Primary cell cultures from rat brain cortex of 17 days g.a. were irradiated with a gamma source, with doses between 0.2 Gy to 2 Gy. Apoptosis was evaluated 4 hours and 20 hours after irradiation by hematoxylin/eosin, fluorescent microscopy, flow cytometry and DNA electrophoresis. It was also evaluated the neuro protective effect of L-NAME, SOD and glutathion. A dose-dependent increase in apoptotic cell fraction was observed. A protector effect related with the presence of glutathion was observed. (author) [es

  19. Study of ATM Phosphorylation by Cdk5 in Neuronal Cells.

    Science.gov (United States)

    She, Hua; Mao, Zixu

    2017-01-01

    The phosphatidylinositol-3-kinase-like kinase ATM (ataxia-telangiectasia mutated) plays a central role in coordinating the DNA damage responses including cell cycle checkpoint control, DNA repair, and apoptosis. Mutations of ATM cause a spectrum of defects ranging from neurodegeneration to cancer predisposition. We previously showed that Cdk5 (cyclin-dependent kinase 5) is activated by DNA damage and directly phosphorylates ATM at serine 794 in postmitotic neurons. Phosphorylation at serine 794 precedes and is required for ATM autophosphorylation at serine 1981, and activates ATM kinase activity. Cdk5-ATM pathway plays a crucial role in DNA damage-induced neuronal injury. This chapter describes protocols used in analyzing ATM phosphorylation by Cdk5 in CGNs (cerebellar granule neurons) and its effects on neuronal survival.

  20. Regulation of Neuronal Protein Trafficking and Translocation by SUMOylation

    Directory of Open Access Journals (Sweden)

    Jeremy M. Henley

    2012-05-01

    Full Text Available Post-translational modifications of proteins are essential for cell function. Covalent modification by SUMO (small ubiquitin-like modifier plays a role in multiple cell processes, including transcriptional regulation, DNA damage repair, protein localization and trafficking. Factors affecting protein localization and trafficking are particularly crucial in neurons because of their polarization, morphological complexity and functional specialization. SUMOylation has emerged as a major mediator of intranuclear and nucleo-cytoplasmic translocations of proteins involved in critical pathways such as circadian rhythm, apoptosis and protein degradation. In addition, SUMO-regulated re-localization of extranuclear proteins is required to sustain neuronal excitability and synaptic transmission. Thus, SUMOylation is a key arbiter of neuronal viability and function. Here, we provide an overview of recent advances in our understanding of regulation of neuronal protein localization and translocation by SUMO and highlight exciting areas of ongoing research.

  1. BIG1 is required for the survival of deep layer neurons, neuronal polarity, and the formation of axonal tracts between the thalamus and neocortex in developing brain.

    Directory of Open Access Journals (Sweden)

    Jia-Jie Teoh

    Full Text Available BIG1, an activator protein of the small GTPase, Arf, and encoded by the Arfgef1 gene, is one of candidate genes for epileptic encephalopathy. To know the involvement of BIG1 in epileptic encephalopathy, we analyzed BIG1-deficient mice and found that BIG1 regulates neurite outgrowth and brain development in vitro and in vivo. The loss of BIG1 decreased the size of the neocortex and hippocampus. In BIG1-deficient mice, the neuronal progenitor cells (NPCs and the interneurons were unaffected. However, Tbr1+ and Ctip2+ deep layer (DL neurons showed spatial-temporal dependent apoptosis. This apoptosis gradually progressed from the piriform cortex (PIR, peaked in the neocortex, and then progressed into the hippocampus from embryonic day 13.5 (E13.5 to E17.5. The upper layer (UL and DL order in the neocortex was maintained in BIG1-deficient mice, but the excitatory neurons tended to accumulate before their destination layers. Further pulse-chase migration assay showed that the migration defect was non-cell autonomous and secondary to the progression of apoptosis into the BIG1-deficient neocortex after E15.5. In BIG1-deficient mice, we observed an ectopic projection of corticothalamic axons from the primary somatosensory cortex (S1 into the dorsal lateral geniculate nucleus (dLGN. The thalamocortical axons were unable to cross the diencephalon-telencephalon boundary (DTB. In vitro, BIG1-deficient neurons showed a delay in neuronal polarization. BIG1-deficient neurons were also hypersensitive to low dose glutamate (5 μM, and died via apoptosis. This study showed the role of BIG1 in the survival of DL neurons in developing embryonic brain and in the generation of neuronal polarity.

  2. YAP regulates neuronal differentiation through Sonic hedgehog signaling pathway

    International Nuclear Information System (INIS)

    Lin, Yi-Ting; Ding, Jing-Ya; Li, Ming-Yang; Yeh, Tien-Shun; Wang, Tsu-Wei; Yu, Jenn-Yah

    2012-01-01

    Tight regulation of cell numbers by controlling cell proliferation and apoptosis is important during development. Recently, the Hippo pathway has been shown to regulate tissue growth and organ size in Drosophila. In mammalian cells, it also affects cell proliferation and differentiation in various tissues, including the nervous system. Interplay of several signaling cascades, such as Notch, Wnt, and Sonic Hedgehog (Shh) pathways, control cell proliferation during neuronal differentiation. However, it remains unclear whether the Hippo pathway coordinates with other signaling cascades in regulating neuronal differentiation. Here, we used P19 cells, a mouse embryonic carcinoma cell line, as a model to study roles of YAP, a core component of the Hippo pathway, in neuronal differentiation. P19 cells can be induced to differentiate into neurons by expressing a neural bHLH transcription factor gene Ascl1. Our results showed that YAP promoted cell proliferation and inhibited neuronal differentiation. Expression of Yap activated Shh but not Wnt or Notch signaling activity during neuronal differentiation. Furthermore, expression of Yap increased the expression of Patched homolog 1 (Ptch1), a downstream target of the Shh signaling. Knockdown of Gli2, a transcription factor of the Shh pathway, promoted neuronal differentiation even when Yap was over-expressed. We further demonstrated that over-expression of Yap inhibited neuronal differentiation in primary mouse cortical progenitors and Gli2 knockdown rescued the differentiation defect in Yap over-expressing cells. In conclusion, our study reveals that Shh signaling acts downstream of YAP in regulating neuronal differentiation. -- Highlights: ► YAP promotes cell proliferation and inhibits neuronal differentiation in P19 cells. ► YAP promotes Sonic hedgehog signaling activity during neuronal differentiation. ► Knockdown of Gli2 rescues the Yap-overexpression phenotype in P19 cells. ► Knockdown of Gli2 rescues the Yap

  3. YAP regulates neuronal differentiation through Sonic hedgehog signaling pathway

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Yi-Ting; Ding, Jing-Ya [Department of Life Sciences and Institute of Genome Sciences, National Yang-Ming University, Taipei 112, Taiwan (China); Li, Ming-Yang [Department of Life Science, National Taiwan Normal University, Taipei 116, Taiwan (China); Yeh, Tien-Shun [Department of Anatomy and Cell Biology, National Yang-Ming University, Taipei 112, Taiwan (China); Wang, Tsu-Wei [Department of Life Science, National Taiwan Normal University, Taipei 116, Taiwan (China); Yu, Jenn-Yah [Department of Life Sciences and Institute of Genome Sciences, National Yang-Ming University, Taipei 112, Taiwan (China); Brain Research Center, National Yang-Ming University, Taipei 112, Taiwan (China)

    2012-09-10

    Tight regulation of cell numbers by controlling cell proliferation and apoptosis is important during development. Recently, the Hippo pathway has been shown to regulate tissue growth and organ size in Drosophila. In mammalian cells, it also affects cell proliferation and differentiation in various tissues, including the nervous system. Interplay of several signaling cascades, such as Notch, Wnt, and Sonic Hedgehog (Shh) pathways, control cell proliferation during neuronal differentiation. However, it remains unclear whether the Hippo pathway coordinates with other signaling cascades in regulating neuronal differentiation. Here, we used P19 cells, a mouse embryonic carcinoma cell line, as a model to study roles of YAP, a core component of the Hippo pathway, in neuronal differentiation. P19 cells can be induced to differentiate into neurons by expressing a neural bHLH transcription factor gene Ascl1. Our results showed that YAP promoted cell proliferation and inhibited neuronal differentiation. Expression of Yap activated Shh but not Wnt or Notch signaling activity during neuronal differentiation. Furthermore, expression of Yap increased the expression of Patched homolog 1 (Ptch1), a downstream target of the Shh signaling. Knockdown of Gli2, a transcription factor of the Shh pathway, promoted neuronal differentiation even when Yap was over-expressed. We further demonstrated that over-expression of Yap inhibited neuronal differentiation in primary mouse cortical progenitors and Gli2 knockdown rescued the differentiation defect in Yap over-expressing cells. In conclusion, our study reveals that Shh signaling acts downstream of YAP in regulating neuronal differentiation. -- Highlights: Black-Right-Pointing-Pointer YAP promotes cell proliferation and inhibits neuronal differentiation in P19 cells. Black-Right-Pointing-Pointer YAP promotes Sonic hedgehog signaling activity during neuronal differentiation. Black-Right-Pointing-Pointer Knockdown of Gli2 rescues the Yap

  4. DL-2-amino-3-phosphonopropionic acid protects primary neurons from oxygen-glucose deprivation induced injury

    Directory of Open Access Journals (Sweden)

    Di Cui

    2017-02-01

    Full Text Available Cerebral infarction is a type of ischemic stroke and is one of the main causes of irreversible brain damage. Although multiple neuroprotective agents have been investigated recently, the potential of DL-2-amino-3-phosphonopropionic acid (DL-AP3 in treating oxygen-glucose deprivation (OGD-induced neuronal injury, has not been clarified yet. This study was aimed to explore the role of DL-AP3 in primary neuronal cell cultures. Primary neurons were divided into four groups: (1 a control group that was not treated; (2 DL-AP3 group treated with 10 μM of DL-AP3; (3 OGD group, in which neurons were cultured under OGD conditions; and (4 OGD + DL-AP3 group, in which OGD model was first established and then the cells were treated with 10 μM of DL-AP3. Neuronal viability and apoptosis were measured using Cell Counting Kit-8 and flow cytometry. Expressions of phospho-Akt1 (p-Akt1 and cytochrome c were detected using Western blot. The results showed that DL-AP3 did not affect neuronal viability and apoptosis in DL-AP3 group, nor it changed p-Akt1 and cytochrome c expression (p > 0.05. In OGD + DL-AP3 group, DL-AP3 significantly attenuated the inhibitory effects of OGD on neuronal viability (p < 0.001, and reduced OGD induced apoptosis (p < 0.01. Additionally, the down-regulation of p-Akt1 and up-regulation of cytochrome c, induced by OGD, were recovered to some extent after DL-AP3 treatment (p < 0.05 or p < 0.001. Overall, DL-AP3 could protect primary neurons from OGD-induced injury by affecting the viability and apoptosis of neurons, and by regulating the expressions of p-Akt1 and cytochrome c.

  5. Molecular cloning of cDNA for rat brain metallothionein-2 and regulation of its gene expression

    Energy Technology Data Exchange (ETDEWEB)

    Saijoh, Kiyofumi; Sumino, Kimiaki [Department of Public Health, Kobe University School of Medicine (Japan); Kuno, Takayoshi; Shuntoh, Hisato; Tanaka, Chikako [Department of Pharmacology, Kobe University of Medicine (Japan)

    1989-01-01

    A rat brain metallothionein-II (MT-II) complementary DNA (cDNA) clone was isolated from a cDNA plasmid library, which was prepared from non-treated rat brain mRNA, by a colony screening procedure using /sup 32/P-labeled synthetic oligonucleotide probes. It is deduced that the clone encodes for a protein of 61 amino acids comprising 20 cysteines, which is highly homologous to MT-IIs in other species. Northern blot analysis demonstrated major mRNA species in the brain, liver and kidneys (approximately 350 b in size), which is induced in response to dexamethasone, zinc, cadmium and mercury but not to methyl mercury. These findings confirm that MT-II genes are expressed and regulated both by steroid and heavy metals in the brain as well as in peripheral organs. (author).

  6. Metallothionein 2A affects the cell respiration by suppressing the expression of mitochondrial protein cytochrome c oxidase subunit II.

    Science.gov (United States)

    Bragina, Olga; Gurjanova, Karina; Krishtal, Jekaterina; Kulp, Maria; Karro, Niina; Tõugu, Vello; Palumaa, Peep

    2015-06-01

    Metallothioneins (MT) are involved in a broad range of cellular processes and play a major role in protection of cells towards various stressors. Two functions of MTs, namely the maintaining of the homeostasis of transition metal ions and the redox balance, are directly linked to the functioning of mitochondria. Dyshomeostasis of MTs is often related with malfunctioning of mitochondria; however, the mechanism by which MTs affect the mitochondrial respiratory chain is still unknown. We demonstrated that overexpression of MT-2A in HEK cell line decreased the oxidative phosphorylation capacity of the cells. HEK cells overexpressing MT-2A demonstrated reduced oxygen consumption and lower cellular ATP levels. MT-2A did not affect the number of mitochondria, but reduced specifically the level of cytochrome c oxidase subunit II protein, which resulted in lower activity of the complex IV.

  7. Effect of thermal processing and canning on cadmium and lead levels in California market squid: the role of metallothioneins.

    Science.gov (United States)

    Galitsopoulou, A; Georgantelis, D; Kontominas, M G

    2013-01-01

    The effects of two common seafood preparation practices (roasting and industrial canning) on the heavy metal content--cadmium (Cd) and lead (Pb)--of various tissues of California market squid were studied. Emphasis was placed on the role of metallothioneins (MT) in Cd and Pb behaviour during processing. Cd and Pb analysis was conducted by a Zeeman GTA-AAS atomic absorption spectrometry system; MT analysis was performed by a mercury saturation assay. Results showed that Cd levels in the mantle and whole squid were considerably affected by both processing practices, reaching a 240% increase in mantle and a 40% increase in whole squid. Interestingly, Cd behaviour was associated with MT changes during squid processing. On the other hand, Pb content was not affected from either processing or associated with MT content in the raw or processed squid. Therefore, processing operations may affect Cd and Pb content differently due to the specific metal bioaccumulation and chemical features of each heavy metal type.

  8. Molecular cloning of cDNA for rat brain metallothionein-2 and regulation of its gene expression

    International Nuclear Information System (INIS)

    Saijoh, Kiyofumi; Sumino, Kimiaki; Kuno, Takayoshi; Shuntoh, Hisato; Tanaka, Chikako

    1989-01-01

    A rat brain metallothionein-II (MT-II) complementary DNA (cDNA) clone was isolated from a cDNA plasmid library, which was prepared from non-treated rat brain mRNA, by a colony screening procedure using 32 P-labeled synthetic oligonucleotide probes. It is deduced that the clone encodes for a protein of 61 amino acids comprising 20 cysteines, which is highly homologous to MT-IIs in other species. Northern blot analysis demonstrated major mRNA species in the brain, liver and kidneys (approximately 350 b in size), which is induced in response to dexamethasone, zinc, cadmium and mercury but not to methyl mercury. These findings confirm that MT-II genes are expressed and regulated both by steroid and heavy metals in the brain as well as in peripheral organs. (author)

  9. Metallothionein-mediated antioxidant defense system and its response to exercise training are impaired in human type 2 diabetes

    DEFF Research Database (Denmark)

    Scheede-Bergdahl, Celena; Penkowa, Milena; Hidalgo, Juan

    2005-01-01

    lower levels of MT-I+II were also detected in the plasma of type 2 diabetic subjects compared with control subjects. These results suggest that, in control subjects, the MT-I+II defense system is active and inducible within skeletal muscle tissue and plasma. In type 2 diabetes, reduced levels of MT......Oxidative stress is implicated in diabetes complications, during which endogenous antioxidant defenses have important pathophysiological consequences. To date, the significance of endogenous antioxidants such as metallothioneins I and II (MT-I+II) in type 2 diabetes remains unclear. To examine....... Immunohistochemical analysis revealed reduced MT-I+II levels in the skeletal muscle of type 2 diabetic subjects compared with control subjects. Control subjects produced a robust increase of MT-I+II in response to training; however, in type 2 diabetes, MT-I+II levels remained essentially unchanged. Significantly...

  10. Corvitin restores metallothionein and glial fibrillary acidic protein levels in rat brain affected by pituitrin-izadrin

    Directory of Open Access Journals (Sweden)

    H. N. Shiyntum

    2017-06-01

    Full Text Available In this research, we investigated the effect of pituitrin-izadrin induced injury on the levels of metallothionein (MT and soluble and filament forms of glial fibrillary acidic protein (GFAP in the hippocampus, cerebellum, thalamus, and the cerebral cortex, and examined the effect of corvitin on the brain under the noted changes. Our results showed oppositely directed changes – a decrease in the level of MT and an increase in GFAP in the rat brain, with a tendency to astrogliosis development, under the influence of systemic deficiencies in myocardial function. The use of corvitin at a dose of 42 mg/kg for five days after a cardiac attack caused by pituitary-izadrin leads to recovery in the balance of the studied proteins.

  11. Trace-elements, methylmercury and metallothionein levels in Magellanic penguin (Spheniscus magellanicus) found stranded on the Southern Brazilian coast.

    Science.gov (United States)

    Kehrig, Helena A; Hauser-Davis, Rachel A; Seixas, Tércia G; Fillmann, Gilberto

    2015-07-15

    Magellanic penguins have been reported as good biomonitors for several types of pollutants, including trace-elements. In this context, selenium (Se), total mercury, methylmercury, inorganic mercury (Hg(inorg)), cadmium (Cd) and lead (Pb), as well as metallothionein (MT) levels, were evaluated in the feathers, liver and kidney of juvenile Magellanic penguins found stranded along the coast of Southern Brazil. The highest concentrations of all trace-elements and methylmercury were found in internal organs. Concentrations of Cd and Se in feathers were extremely low in comparison with their concentrations in soft tissues. The results showed that both Se and MT are involved in the detoxification of trace-elements (Cd, Pb and Hg(inorg)) since statistically significant relationships were found in liver. Conversely, hepatic Se was shown to be the only detoxifying agent for methylmercury. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Effect of cadmium on glutathione S-transferase and metallothionein gene expression in coho salmon liver, gill and olfactory tissues

    International Nuclear Information System (INIS)

    Espinoza, Herbert M.; Williams, Chase R.; Gallagher, Evan P.

    2012-01-01

    Highlights: ► Developed qPCR assays to distinguish closely related GST isoforms in salmon. ► Examined the effect of cadmium on GST and metallothionein genes in 3 tissues. ► Modulation of GST varied among isoforms, tissues, and included a loss of expression. ► Metallothionein outperformed, but generally complemented, GSTs as biomarkers. ► Salmon olfactory genes were among the most responsive to cadmium. - Abstract: The glutathione S-transferases (GSTs) are a multifunctional family of phase II enzymes that detoxify a variety of environmental chemicals, reactive intermediates, and secondary products of oxidative damage. GST mRNA expression and catalytic activity have been used as biomarkers of exposure to environmental chemicals. However, factors such as species differences in induction, partial analyses of multiple GST isoforms, and lack of understanding of fish GST gene regulation, have confounded the use of GSTs as markers of pollutant exposure. In the present study, we examined the effect of exposure to cadmium (Cd), a prototypical environmental contaminant and inducer of mammalian GST, on GST mRNA expression in coho salmon (Oncorhynchus kisutch) liver, gill, and olfactory tissues. GST expression data were compared to those for metallothionein (MT), a prototypical biomarker of metal exposure. Data mining of genomic databases led to the development of quantitative real-time PCR (qPCR) assays for salmon GST isoforms encompassing 9 subfamilies, including alpha, mu, pi, theta, omega, kappa, rho, zeta and microsomal GST. In vivo acute (8–48 h) exposures to low (3.7 ppb) and high (347 ppb) levels of Cd relevant to environmental scenarios elicited a variety of transient, albeit minor changes (<2.5-fold) in tissue GST profiles, including some reductions in GST mRNA expression. In general, olfactory GSTs were the earliest to respond to cadmium, whereas, more pronounced effects in olfactory and gill GST expression were observed at 48 h relative to earlier time

  13. Effects of gamma-ray-induced free radicals on the metal content and amino acid composition of human metallothionein-1

    International Nuclear Information System (INIS)

    Goossens, Lieven

    2011-01-01

    Metallothioneins (MTs), a low-mass class of metalloproteins, are characterized by a high thiolate sulphur and metal content. MTs are involved in metal homeostasis and heavy metal detoxification, and are efficient scavengers of free radicals. This article describes zinc release from human MT-1 and modification of its amino acid composition when subjected to free radicals generated during gamma ray radiolysis. The effect of gamma ray radiolysis of untreated and metal-depleted human MT-1 was tested under multiple aerobic and anaerobic conditions at increasing irradiation doses. Under all conditions, a rapid increase of serine in the early stages of irradiation was observed. Irradiation for longer times led to cysteic acid formation, except under argon atmosphere. Several other amino acid concentrations gradually decreased. Formation of limited amounts of hydroxyproline, hydroxylysine and ornithine as well as some less common derivatives such as cystathionine occurred as side-effects. (author)

  14. Confocal microscope is able to detect calcium metabolic in neuronal infection by toxoplasma gondii

    International Nuclear Information System (INIS)

    Sensusiati, A D; Priya, T K S; Dachlan, Y P

    2017-01-01

    Calcium metabolism plays a very important role in neurons infected by Toxoplasma. Detection of change of calcium metabolism of neuron infected by Toxoplasma and Toxoplasma requires the calculation both quantitative and qualitative method. Confocal microscope has the ability to capture the wave of the fluorescent emission of the fluorescent dyes used in the measurement of cell calcium. The purpose of this study was to prove the difference in calcium changes between infected and uninfected neurons using confocal microscopy. Neuronal culture of human-skin-derived neural stem cell were divided into 6 groups, consisting 3 uninfected groups and 3 infected groups. Among the 3 groups were 2 hours, 24 hours and 48 hours. The neuron Toxoplasma gondii ratio was 1:5. Observation of intracellular calcium of neuron and tachyzoite, evidence of necrosis, apoptosis and the expression of Hsp 70 of neuron were examined by confocal microscope. The normality of the data was analysed by Kolmogorov-Smirnov Test, differentiation test was checked by t2 Test, and ANOVAs, for correlation test was done by Pearson Correlation Test. The calcium intensity of cytosolic neuron and T. gondii was significantly different from control groups (p<0.05). There was also significant correlation between calcium intensity with the evidence of necrosis and Hsp70 expression at 2 hours after infection. Apoptosis and necrosis were simultaneously shown with calcium contribution in this study. Confocal microscopy can be used to measure calcium changes in infected and uninfected neurons both in quantitatively and qualitatively. (paper)

  15. Expression and characterization analysis of type 2 metallothionein from grey mangrove species (Avicennia marina) in response to metal stress

    Energy Technology Data Exchange (ETDEWEB)

    Huang Guoyong, E-mail: huang_gyh@sina.com [Key Laboratory of Tropical Marine Environmental Dynamics, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301 (China); State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China); Wang Youshao [Key Laboratory of Tropical Marine Environmental Dynamics, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301 (China)

    2010-08-01

    Metallothioneins (MTs) are a family of low-molecular-weight cysteine-rich proteins and are thought to play possible roles in metal metabolism or detoxification. To evaluate the roles of metallothioneins in metal homeostasis or tolerance in Avicennia marina, a real-time quantitative PCR protocol was developed to directly evaluate the expression of AmMT2 mRNA, when A. marina seedlings were exposed to different concentrations of zinc (Zn), copper (Cu) or lead (Pb) for 3 and 7 d. Real-time quantitative PCR results indicated that the regulation of AmMT2 mRNA expression by Zn, Cu and Pb was strongly dependent on concentration and time of exposure. A significant increase in the transcripts of AmMT2 gene was also found in response to Zn, Cu and Pb, at least under some experimental conditions. When AmMT2 was overexpressed in Escherichia coli BL21 as a carboxy-terminal extension of glutathione-S-transferase (GST), the transgenic bacteria showed an increased tolerance to Zn, Cu, Pb and Cd exposure as compared to control strains. Moreover, GST-AmMT2 was purified from E. coli cells grown in the presence of 400 {mu}M Zn, Cu, Pb or Cd. The purified GST-AmMT2 fusion protein could bind higher levels of all four metals than GST alone. Taken together, these data support the hypothesis that AmMT2 may be involved in processes of metal homeostasis or tolerance in A. marina.

  16. Genetic variation in metallothionein and metal-regulatory transcription factor 1 in relation to urinary cadmium, copper, and zinc

    International Nuclear Information System (INIS)

    Adams, Scott V.; Barrick, Brian; Christopher, Emily P.; Shafer, Martin M.; Makar, Karen W.; Song, Xiaoling; Lampe, Johanna W.; Vilchis, Hugo; Ulery, April; Newcomb, Polly A.

    2015-01-01

    Background: Metallothionein (MT) proteins play critical roles in the physiological handling of both essential (Cu and Zn) and toxic (Cd) metals. MT expression is regulated by metal-regulatory transcription factor 1 (MTF1). Hence, genetic variation in the MT gene family and MTF1 might influence excretion of these metals. Methods: 321 women were recruited in Seattle, WA and Las Cruces, NM and provided demographic information, urine samples for measurement of metal concentrations by mass spectrometry and creatinine, and blood or saliva for extraction of DNA. Forty-one single nucleotide polymorphisms (SNPs) within the MTF1 gene region and the region of chromosome 16 encoding the MT gene family were selected for genotyping in addition to an ancestry informative marker panel. Linear regression was used to estimate the association of SNPs with urinary Cd, Cu, and Zn, adjusted for age, urinary creatinine, smoking history, study site, and ancestry. Results: Minor alleles of rs28366003 and rs10636 near the MT2A gene were associated with lower urinary Cd, Cu, and Zn. Minor alleles of rs8044719 and rs1599823, near MT1A and MT1B, were associated with lower urinary Cd and Zn, respectively. Minor alleles of rs4653329 in MTF1 were associated with lower urinary Cd. Conclusions: These results suggest that genetic variation in the MT gene region and MTF1 influences urinary Cd, Cu, and Zn excretion. - Highlights: • Genetic variation in metallothionein (MT) genes was assessed in two diverse populations. • Single nucleotide polymorphisms (SNPs) in MT genes were associated with mean urinary Cd, Cu and Zn. • Genetic variation may influence biomarkers of exposure, and associations of exposure with health.

  17. Bone mineral density and polymorphisms in metallothionein 1A and 2A in a Chinese population exposed to cadmium

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Xiao [Department of Bone Metabolism, Institute of Radiation Medicine, Fudan University, Shanghai 200032 (China); Lei, Lijian [Department of Occupation Health, School of Public Health, Fudan University, Shanghai 200032 (China); Department of Epidemiology, School of Public Health, Shanxi Medical University, Shanxi 030001 (China); Tian, Liting [Department of Occupation Health, School of Public Health, Fudan University, Shanghai 200032 (China); Zhu, Guoying, E-mail: chx_win@hotmail.com [Department of Bone Metabolism, Institute of Radiation Medicine, Fudan University, Shanghai 200032 (China); Jin, Taiyi, E-mail: tyjin@shmu.edu.cn [Department of Occupation Health, School of Public Health, Fudan University, Shanghai 200032 (China)

    2012-04-15

    Cadmium (Cd) effect on bone varies between individuals. We investigated whether genetic variation in metallothionein (MT)1A and MT2A associated with Cd induced bone loss in this study. A total of 465 persons (311 women and 154 men), living in control, moderately and heavily polluted areas, participated. The participants completed a questionnaire and the bone mineral density (BMD) was measured by dual energy x-ray absorptiometry (DXA) at the proximal radius and ulna. Samples of urine and blood were collected for determination of Cd in urine (UCd) and blood (BCd). Genotypes for polymorphisms in MT1A (rs11076161) and MT2A (rs10636) were determined by Taqman allelic discrimination assays. BCd had a weak association with variant alleles for MT1A (rs11076161) and MT2A (rs10636) in female living in the highly polluted group (p = 0.08 and 0.05, respectively). A weak association was found between bone mineral density and MT2A polymorphisms variation (p = 0.06) in female living in the highly polluted group. Only a weak association was found between bone mineral density and MT1A polymorphisms variation in female. Genetic variation in the MT1A and MT2A genes may not associate with bone loss caused by cadmium exposure. - Highlights: Black-Right-Pointing-Pointer We investigated the association between metallothionein polymorphisms bone mineral density. Black-Right-Pointing-Pointer MT1A and MT2A polymorphisms showed a weak association with cadmium in blood. Black-Right-Pointing-Pointer MT1A and MT2A polymorphisms showed no association with bone mineral density.

  18. Genetic variation in metallothionein and metal-regulatory transcription factor 1 in relation to urinary cadmium, copper, and zinc

    Energy Technology Data Exchange (ETDEWEB)

    Adams, Scott V., E-mail: sadams@fhcrc.org [Public Health Sciences Division, Fred Hutchinson Cancer Research Center, 1100 Fairview Ave N, Seattle, WA 98109 (United States); Barrick, Brian [Department of Plant and Environmental Sciences, New Mexico State University, Box 30003 MSC 3Q, Las Cruces, NM 88003 (United States); Christopher, Emily P. [Public Health Sciences Division, Fred Hutchinson Cancer Research Center, 1100 Fairview Ave N, Seattle, WA 98109 (United States); Shafer, Martin M. [Environmental Chemistry and Technology, Wisconsin State Laboratory of Hygiene, University of Wisconsin, 2601 Agriculture Dr., Madison, WI 53718 (United States); Makar, Karen W.; Song, Xiaoling [Public Health Science Biomarker Laboratory, Fred Hutchinson Cancer Research Center, 1100 Fairview Ave N, Seattle, WA 98109 (United States); Lampe, Johanna W. [Public Health Sciences Division, Fred Hutchinson Cancer Research Center, 1100 Fairview Ave N, Seattle, WA 98109 (United States); Vilchis, Hugo [Border Epidemiology and Environmental Health Center, New Mexico State University, Box 30001 MSC 3BEC, Las Cruces, NM 88003 (United States); Ulery, April [Department of Plant and Environmental Sciences, New Mexico State University, Box 30003 MSC 3Q, Las Cruces, NM 88003 (United States); Newcomb, Polly A. [Public Health Sciences Division, Fred Hutchinson Cancer Research Center, 1100 Fairview Ave N, Seattle, WA 98109 (United States)

    2015-12-15

    Background: Metallothionein (MT) proteins play critical roles in the physiological handling of both essential (Cu and Zn) and toxic (Cd) metals. MT expression is regulated by metal-regulatory transcription factor 1 (MTF1). Hence, genetic variation in the MT gene family and MTF1 might influence excretion of these metals. Methods: 321 women were recruited in Seattle, WA and Las Cruces, NM and provided demographic information, urine samples for measurement of metal concentrations by mass spectrometry and creatinine, and blood or saliva for extraction of DNA. Forty-one single nucleotide polymorphisms (SNPs) within the MTF1 gene region and the region of chromosome 16 encoding the MT gene family were selected for genotyping in addition to an ancestry informative marker panel. Linear regression was used to estimate the association of SNPs with urinary Cd, Cu, and Zn, adjusted for age, urinary creatinine, smoking history, study site, and ancestry. Results: Minor alleles of rs28366003 and rs10636 near the MT2A gene were associated with lower urinary Cd, Cu, and Zn. Minor alleles of rs8044719 and rs1599823, near MT1A and MT1B, were associated with lower urinary Cd and Zn, respectively. Minor alleles of rs4653329 in MTF1 were associated with lower urinary Cd. Conclusions: These results suggest that genetic variation in the MT gene region and MTF1 influences urinary Cd, Cu, and Zn excretion. - Highlights: • Genetic variation in metallothionein (MT) genes was assessed in two diverse populations. • Single nucleotide polymorphisms (SNPs) in MT genes were associated with mean urinary Cd, Cu and Zn. • Genetic variation may influence biomarkers of exposure, and associations of exposure with health.

  19. Anchoring plant metallothioneins to the inner face of the plasma membrane of Saccharomyces cerevisiae cells leads to heavy metal accumulation.

    Directory of Open Access Journals (Sweden)

    Lavinia Liliana Ruta

    Full Text Available In this study we engineered yeast cells armed for heavy metal accumulation by targeting plant metallothioneins to the inner face of the yeast plasma membrane. Metallothioneins (MTs are cysteine-rich proteins involved in the buffering of excess metal ions, especially Cu(I, Zn(II or Cd(II. The cDNAs of seven Arabidopsis thaliana MTs (AtMT1a, AtMT1c, AtMT2a, AtMT2b, AtMT3, AtMT4a and AtMT4b and four Noccaea caerulescens MTs (NcMT1, NcMT2a, NcMT2b and NcMT3 were each translationally fused to the C-terminus of a myristoylation green fluorescent protein variant (myrGFP and expressed in Saccharomyces cerevisiae cells. The myrGFP cassette introduced a yeast myristoylation sequence which allowed directional targeting to the cytosolic face of the plasma membrane along with direct monitoring of the intracellular localization of the recombinant protein by fluorescence microscopy. The yeast strains expressing plant MTs were investigated against an array of heavy metals in order to identify strains which exhibit the (hyperaccumulation phenotype without developing toxicity symptoms. Among the transgenic strains which could accumulate Cu(II, Zn(II or Cd(II, but also non-canonical metal ions, such as Co(II, Mn(II or Ni(II, myrGFP-NcMT3 qualified as the best candidate for bioremediation applications, thanks to the robust growth accompanied by significant accumulative capacity.

  20. Effect of quercetin on metallothionein, nitric oxide synthases and cyclooxygenase-2 expression on experimental chronic cadmium nephrotoxicity in rats

    International Nuclear Information System (INIS)

    Morales, Ana I.; Vicente-Sanchez, Cesar; Jerkic, Mirjana; Santiago, Jose M.; Sanchez-Gonzalez, Penelope D.; Perez-Barriocanal, Fernando; Lopez-Novoa, Jose M.

    2006-01-01

    Inflammation can play a key role in Cd-induced dysfunctions. Quercetin is a potent oxygen free radical scavenger and a metal chelator. Our aim was to study the effect of quercetin on Cd-induced kidney damage and metallothionein expression. The study was performed in Wistar rats that were administered during 9 weeks with either cadmium (1.2 mg Cd/kg/day, s.c.), quercetin (50 mg/kg/day, i.p.) or cadmium + quercetin. Renal toxicity was evaluated by measuring blood urea nitrogen concentration and urinary excretion of enzymes marker of tubular damage. Endothelial nitric oxide synthase (eNOS), inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) renal expression were assessed by Western blot. Renal expression of metallothionein 1 and 2 (MT-1, MT-2) and eNOS mRNA was assessed by Northern blot. Our data demonstrated that Cd-induced renal toxicity was markedly reduced in rats that also received quercetin. MT-1 and MT-2 mRNA levels in kidney were substantially increased during treatment with Cd, being even higher when the animals received Cd and quercetin. Renal eNOS expression was significantly higher in rats receiving Cd and quercetin than in animals receiving Cd alone or in control rats. In the group that received Cd, COX-2 and iNOS expression was markedly higher than in control rats. In the group Cd + quercetin, no changes in COX-2 and iNOS expression were observed compared with the control group. Our results demonstrate that quercetin treatment prevents Cd-induced overexpression of iNOS and COX-2, and increases MT expression. These effects can explain the protection by quercetin of Cd-induced nephrotoxicity

  1. Anchoring plant metallothioneins to the inner face of the plasma membrane of Saccharomyces cerevisiae cells leads to heavy metal accumulation.

    Science.gov (United States)

    Ruta, Lavinia Liliana; Lin, Ya-Fen; Kissen, Ralph; Nicolau, Ioana; Neagoe, Aurora Daniela; Ghenea, Simona; Bones, Atle M; Farcasanu, Ileana Cornelia

    2017-01-01

    In this study we engineered yeast cells armed for heavy metal accumulation by targeting plant metallothioneins to the inner face of the yeast plasma membrane. Metallothioneins (MTs) are cysteine-rich proteins involved in the buffering of excess metal ions, especially Cu(I), Zn(II) or Cd(II). The cDNAs of seven Arabidopsis thaliana MTs (AtMT1a, AtMT1c, AtMT2a, AtMT2b, AtMT3, AtMT4a and AtMT4b) and four Noccaea caerulescens MTs (NcMT1, NcMT2a, NcMT2b and NcMT3) were each translationally fused to the C-terminus of a myristoylation green fluorescent protein variant (myrGFP) and expressed in Saccharomyces cerevisiae cells. The myrGFP cassette introduced a yeast myristoylation sequence which allowed directional targeting to the cytosolic face of the plasma membrane along with direct monitoring of the intracellular localization of the recombinant protein by fluorescence microscopy. The yeast strains expressing plant MTs were investigated against an array of heavy metals in order to identify strains which exhibit the (hyper)accumulation phenotype without developing toxicity symptoms. Among the transgenic strains which could accumulate Cu(II), Zn(II) or Cd(II), but also non-canonical metal ions, such as Co(II), Mn(II) or Ni(II), myrGFP-NcMT3 qualified as the best candidate for bioremediation applications, thanks to the robust growth accompanied by significant accumulative capacity.

  2. Methylselenium and Prostate Cancer Apoptosis

    National Research Council Canada - National Science Library

    Lu, Junxuan

    2004-01-01

    The purpose of this research is to gain a better understanding of the biochemical pathways and molecular targets for the selective induction of apoptosis signaling and execution of PCa cells by methyl selenium (Se)/selenol...

  3. Methylselenium and Prostate Cancer Apoptosis

    National Research Council Canada - National Science Library

    Lu, Junxuan

    2008-01-01

    The purpose of this research is to gain a better understanding of the biochemical pathways and molecular targets for the selective induction of apoptosis signaling and execution of prostate cancer (PCa...

  4. Methylselenium and Prostate Cancer Apoptosis

    National Research Council Canada - National Science Library

    Lu, Junxuan

    2003-01-01

    The purpose of this research is to gain a better understanding of the biochemical pathways and molecular targets for the selective induction of apoptosis signaling and execution of PCa cells by methyl selenium (Se...

  5. Methylselenium and Prostate Cancer Apoptosis

    National Research Council Canada - National Science Library

    Lu, Junxuan

    2005-01-01

    The purpose of this research is to gain a better understanding of the biochemical pathways and molecular targets for the selective induction of apoptosis signaling and execution of prostate cancer (PCa...

  6. Methylselenium and Prostate Cancer Apoptosis

    National Research Council Canada - National Science Library

    Lu, Junxuan

    2007-01-01

    The purpose of this research is to gain a better understanding of the biochemical pathways and molecular targets for the selective induction of apoptosis signaling and execution of prostate cancer (PCa...

  7. Methylselenium and Prostate Cancer Apoptosis

    National Research Council Canada - National Science Library

    Lu, Junxuan

    2006-01-01

    The purpose of this research is to gain a better understanding of the biochemical pathways and molecular targets for the selective induction of apoptosis signaling and execution of prostate cancer (PCa...

  8. Neuronal apoptotic signaling pathways probed and intervened by synthetically and modularly modified (SMM) chemokines.

    Science.gov (United States)

    Choi, Won-Tak; Kaul, Marcus; Kumar, Santosh; Wang, Jun; Kumar, I M Krishna; Dong, Chang-Zhi; An, Jing; Lipton, Stuart A; Huang, Ziwei

    2007-03-09

    As the main coreceptors for human immunodeficiency virus type 1 (HIV-1) entry, CXCR4 and CCR5 play important roles in HIV-associated dementia (HAD). HIV-1 glycoprotein gp120 contributes to HAD by causing neuronal damage and death, either directly by triggering apoptotic pathways or indirectly by stimulating glial cells to release neurotoxins. Here, to understand the mechanism of CXCR4 or CCR5 signaling in neuronal apoptosis associated with HAD, we have applied synthetically and modularly modified (SMM)-chemokine analogs derived from natural stromal cell-derived factor-1alpha or viral macrophage inflammatory protein-II as chemical probes of the mechanism(s) whereby these SMM-chemokines prevent or promote neuronal apoptosis. We show that inherently neurotoxic natural ligands of CXCR4, such as stromal cell-derived factor-1alpha or viral macrophage inflammatory protein-II, can be modified to protect neurons from apoptosis induced by CXCR4-preferring gp120(IIIB), and that the inhibition of CCR5 by antagonist SMM-chemokines, unlike neuroprotective CCR5 natural ligands, leads to neurotoxicity by activating a p38 mitogen-activated protein kinase (MAPK)-dependent pathway. Furthermore, we discover distinct signaling pathways activated by different chemokine ligands that are either natural agonists or synthetic antagonists, thus demonstrating a chemical biology strategy of using chemically engineered inhibitors of chemokine receptors to study the signaling mechanism of neuronal apoptosis and survival.

  9. Lymphotropic Virions Affect Chemokine Receptor-Mediated Neural Signaling and Apoptosis: Implications for Human Immunodeficiency Virus Type 1-Associated Dementia

    Science.gov (United States)

    Zheng, Jialin; Ghorpade, Anuja; Niemann, Douglas; Cotter, Robin L.; Thylin, Michael R.; Epstein, Leon; Swartz, Jennifer M.; Shepard, Robin B.; Liu, Xiaojuan; Nukuna, Adeline; Gendelman, Howard E.

    1999-01-01

    Chemokine receptors pivotal for human immunodeficiency virus type 1 (HIV-1) infection in lymphocytes and macrophages (CCR3, CCR5, and CXCR4) are expressed on neural cells (microglia, astrocytes, and/or neurons). It is these cells which are damaged during progressive HIV-1 infection of the central nervous system. We theorize that viral coreceptors could effect neural cell damage during HIV-1-associated dementia (HAD) without simultaneously affecting viral replication. To these ends, we studied the ability of diverse viral strains to affect intracellular signaling and apoptosis of neurons, astrocytes, and monocyte-derived macrophages. Inhibition of cyclic AMP, activation of inositol 1,4,5-trisphosphate, and apoptosis were induced by diverse HIV-1 strains, principally in neurons. Virions from T-cell-tropic (T-tropic) strains (MN, IIIB, and Lai) produced the most significant alterations in signaling of neurons and astrocytes. The HIV-1 envelope glycoprotein, gp120, induced markedly less neural damage than purified virions. Macrophage-tropic (M-tropic) strains (ADA, JR-FL, Bal, MS-CSF, and DJV) produced the least neural damage, while 89.6, a dual-tropic HIV-1 strain, elicited intermediate neural cell damage. All T-tropic strain-mediated neuronal impairments were blocked by the CXCR4 antibody, 12G5. In contrast, the M-tropic strains were only partially blocked by 12G5. CXCR4-mediated neuronal apoptosis was confirmed in pure populations of rat cerebellar granule neurons and was blocked by HA1004, an inhibitor of calcium/calmodulin-dependent protein kinase II, protein kinase A, and protein kinase C. Taken together, these results suggest that progeny HIV-1 virions can influence neuronal signal transduction and apoptosis. This process occurs, in part, through CXCR4 and is independent of CD4 binding. T-tropic viruses that traffic in and out of the brain during progressive HIV-1 disease may play an important role in HAD neuropathogenesis. PMID:10482576

  10. Acute and subacute pulmonary toxicity caused by a single intratracheal instillation of colloidal silver nanoparticles in mice: pathobiological changes and metallothionein responses.

    Science.gov (United States)

    Kaewamatawong, Theerayuth; Banlunara, Wijit; Maneewattanapinyo, Pattwat; Thammachareon, Chuchaat; Ekgasit, Sanong

    2014-01-01

    To study the acute and subacute pulmonary toxicity of colloidal silver nanoparticles (Ag-NPs), 0 or 100 ppm of Ag-NPs were instilled intratracheally in mice. Cellular and biochemical parameters in bronchoalveolar lavage fluid (BALF) and histological alterations were determined 1, 3, 7, 15, and 30 days after instillation. Ag-NPs induced moderate pulmonary inflammation and injury on BALF indices during the acute period; however, these changes gradually regressed in a time-dependent manner. Concomitant histopathological and laminin immunohistochemical findings generally correlated to BALF data. Superoxide dismutase and metallothionein expression occurred in particle-laden macrophages and alveolar epithelial cells, which correlated to lung lesions in mice treated with Ag-NPs. These findings suggest that instillation of Ag-NPs causes transient moderate acute lung inflammation and tissue damage. Oxidative stress may underlie the induction of injury to lung tissue. Moreover, the expression of metallothionein in tissues indicated the protective response to exposure to Ag-NPs.

  11. Reactive oxygen species regulated mitochondria-mediated apoptosis in PC12 cells exposed to chlorpyrifos

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jeong Eun [Department of Pharmacology, College of Medicine, Hanyang University, Seoul (Korea, Republic of); Hanyang Biomedical Research Institute, Seoul (Korea, Republic of); Park, Jae Hyeon [Hanyang Biomedical Research Institute, Seoul (Korea, Republic of); Graduate School of Biomedical Science and Engineering, Hanyang University, Seoul (Korea, Republic of); Shin, In Chul [Department of Pharmacology, College of Medicine, Hanyang University, Seoul (Korea, Republic of); Koh, Hyun Chul, E-mail: hckoh@hanyang.ac.kr [Department of Pharmacology, College of Medicine, Hanyang University, Seoul (Korea, Republic of); Hanyang Biomedical Research Institute, Seoul (Korea, Republic of); Graduate School of Biomedical Science and Engineering, Hanyang University, Seoul (Korea, Republic of)

    2012-09-01

    Reactive oxidative species (ROS) generated by environmental toxicants including pesticides could be one of the factors underlying the neuronal cell damage in neurodegenerative diseases. In this study we found that chlorpyrifos (CPF) induced apoptosis in dopaminergic neuronal components of PC12 cells as demonstrated by the activation of caspases and nuclear condensation. Furthermore, CPF also reduced the tyrosine hydroxylase-positive immunoreactivity in substantia nigra of the rat. In addition, CPF induced inhibition of mitochondrial complex I activity. Importantly, N-acetyl cysteine (NAC) treatment effectively blocked apoptosis via the caspase-9 and caspase-3 pathways while NAC attenuated the inhibition of mitochondrial complex I activity as well as the oxidative metabolism of dopamine (DA). These results demonstrated that CPF-induced apoptosis was involved in mitochondrial dysfunction through the production of ROS. In the response of cellular antioxidant systems to CPF, we found that CPF treatment increased HO-1 expression while the expression of CuZnSOD and MnSOD was reduced. In addition, we found that CPF treatment activated MAPK pathways, including ERK 1/2, the JNK, and the p38 MAP kinase in a time-dependent manner. NAC treatment abolished MAPK phosphorylation caused by CPF, indicating that ROS are upstream signals of MAPK. Interestingly, MAPK inhibitors abolished cytotoxicity and reduced ROS generation by CPF treatment. Our results demonstrate that CPF induced neuronal cell death in part through MAPK activation via ROS generation, suggesting its potential to generate oxidative stress via mitochondrial damage and its involvement in oxidative stress-related neurodegenerative disease. -- Highlights: ► Chlorpyrifos induces apoptosis. ► Chlorpyrifos inhibits mitochondrial complex I activity. ► ROS is involved in chlorpyrifos-induced apoptosis. ► Chlorpyrifos affects cellular antioxidant systems. ► Chlorpyrifos-induced apoptosis mediates activation of MAPK.

  12. Reactive oxygen species regulated mitochondria-mediated apoptosis in PC12 cells exposed to chlorpyrifos

    International Nuclear Information System (INIS)

    Lee, Jeong Eun; Park, Jae Hyeon; Shin, In Chul; Koh, Hyun Chul

    2012-01-01

    Reactive oxidative species (ROS) generated by environmental toxicants including pesticides could be one of the factors underlying the neuronal cell damage in neurodegenerative diseases. In this study we found that chlorpyrifos (CPF) induced apoptosis in dopaminergic neuronal components of PC12 cells as demonstrated by the activation of caspases and nuclear condensation. Furthermore, CPF also reduced the tyrosine hydroxylase-positive immunoreactivity in substantia nigra of the rat. In addition, CPF induced inhibition of mitochondrial complex I activity. Importantly, N-acetyl cysteine (NAC) treatment effectively blocked apoptosis via the caspase-9 and caspase-3 pathways while NAC attenuated the inhibition of mitochondrial complex I activity as well as the oxidative metabolism of dopamine (DA). These results demonstrated that CPF-induced apoptosis was involved in mitochondrial dysfunction through the production of ROS. In the response of cellular antioxidant systems to CPF, we found that CPF treatment increased HO-1 expression while the expression of CuZnSOD and MnSOD was reduced. In addition, we found that CPF treatment activated MAPK pathways, including ERK 1/2, the JNK, and the p38 MAP kinase in a time-dependent manner. NAC treatment abolished MAPK phosphorylation caused by CPF, indicating that ROS are upstream signals of MAPK. Interestingly, MAPK inhibitors abolished cytotoxicity and reduced ROS generation by CPF treatment. Our results demonstrate that CPF induced neuronal cell death in part through MAPK activation via ROS generation, suggesting its potential to generate oxidative stress via mitochondrial damage and its involvement in oxidative stress-related neurodegenerative disease. -- Highlights: ► Chlorpyrifos induces apoptosis. ► Chlorpyrifos inhibits mitochondrial complex I activity. ► ROS is involved in chlorpyrifos-induced apoptosis. ► Chlorpyrifos affects cellular antioxidant systems. ► Chlorpyrifos-induced apoptosis mediates activation of MAPK.

  13. Effect of metallothionein core promoter region polymorphism on cadmium, zinc and copper levels in autopsy kidney tissues from a Turkish population

    International Nuclear Information System (INIS)

    Kayaalti, Zeliha; Mergen, Goerkem; Soeylemezoglu, Tuelin

    2010-01-01

    Metallothioneins (MTs) are metal-binding, low molecular weight proteins and are involved in pathophysiological processes like metabolism of essential metals, metal ion homeostasis and detoxification of heavy metals. Metallothionein expression is induced by various heavy metals especially cadmium, mercury and zinc; MTs suppress toxicity of heavy metals by binding themselves to these metals. The aim of this study was to investigate the association between the - 5 A/G metallothionein 2A (MT2A) single nucleotide polymorphism (SNP) and Cd, Zn and Cu levels in the renal cortex from autopsy cases. MT2A core promoter region - 5 A/G SNP was analyzed by PCR-RFLP method using 114 autopsy kidney tissues and the genotype frequencies of this polymorphism were found as 87.7% homozygote typical (AA), 11.4% heterozygote (AG) and 0.9% homozygote atypical (GG). In order to assess the Cd, Zn and Cu levels in the same autopsy kidney tissues, a dual atomic absorption spectrophotometer system was used and the average levels of Cd, Zn and Cu were measured as 95.54 ± 65.58 μg/g, 181.20 ± 87.72 μg/g and 17.14 ± 16.28 μg/g, respectively. As a result, no statistical association was found between the - 5 A/G SNP in the MT2A gene and the Zn and Cu levels in the renal cortex (p > 0.05), but considerably high accumulation of Cd was monitored for individuals having AG (151.24 ± 60.21 μg/g) and GG genotypes (153.09 μg/g) compared with individuals having AA genotype (87.72 ± 62.98 μg/g) (p < 0.05). These results show that the core promoter region polymorphism of metallothionein 2A increases the accumulation of Cd in human renal cortex.

  14. Tp53 gene mediates distinct dopaminergic neuronal damage in different dopaminergic neurotoxicant models

    Directory of Open Access Journals (Sweden)

    Tao Lu

    2017-01-01

    Full Text Available Tp53, a stress response gene, is involved in diverse cell death pathways and its activation is implicated in the pathogenesis of Parkinson's disease. However, whether the neuronal Tp53 protein plays a direct role in regulating dopaminergic (DA neuronal cell death or neuronal terminal damage in different neurotoxicant models is unknown. In our recent studies, in contrast to the global inhibition of Tp53 function by pharmacological inhibitors and in traditional Tp53 knock-out mice, we examined the effects of DA-specific Tp53 gene deletion after 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine and methamphetamine exposure. Our data suggests that the Tp53 gene might be involved in both neuronal apoptosis and neuronal terminal damage caused by different neurotoxicants. Additional results from other studies also suggest that as a master regulator of many pathways that regulate apoptosis and synaptic terminal damage, it is possible that Tp53 may function as a signaling hub to integrate different signaling pathways to mediate distinctive target pathways. Tp53 protein as a signaling hub might be able to evaluate the microenvironment of neurons, assess the forms and severities of injury incurred, and determine whether apoptotic cell death or neuronal terminal degeneration occurs. Identification of the precise mechanisms activated in distinct neuronal damage caused by different forms and severities of injuries might allow for development of specific Tp53 inhibitors or ways to modulate distinct downstream target pathways involved.

  15. Neuronal redox imbalance results in altered energy homeostasis and early postnatal lethality.

    Science.gov (United States)

    Maity-Kumar, Gandhari; Thal, Dietmar R; Baumann, Bernd; Scharffetter-Kochanek, Karin; Wirth, Thomas

    2015-07-01

    Redox imbalance is believed to contribute to the development and progression of several neurodegenerative disorders. Our aim was to develop an animal model that exhibits neuron-specific oxidative stress in the CNS to study the consequences and eventually find clues regarding the pathomechanisms of oxidative insults in neuronal homeostasis. We therefore generated a novel neuron-specific superoxide dismutase 2 (SOD2)-deficient mouse by deleting exon 3 of the SOD2 gene using CamKIIα promoter-driven Cre expression. These neuron-specific SOD2 knockout (SOD2(nko)) mice, although born at normal frequencies, died at the age of 4 weeks with critical growth retardation, severe energy failure, and several neurologic phenotypes. In addition, SOD2(nko) mice exhibited severe neuronal alterations such as reactive astrogliosis, neuronal cell cycle inhibition, and induction of apoptosis. JNK activation and stabilization of p53, as a result of reactive oxygen species accumulation, are most likely the inducers of neuronal apoptosis in SOD2(nko) mice. It is remarkable that hypothalamic regulation of glucose metabolism was affected, which in turn induced necrotic brain lesions in SOD2(nko) mice. Taken together, our findings suggest that exclusive deficiency of SOD2 in neurons results in an impaired central regulation of energy homeostasis that leads to persistent hypoglycemia, hypoglycemia-related neuropathology, and an early lethality of the mutant mice. © FASEB.

  16. The balance between life and death of cells: Roles of Metallothioneins

    DEFF Research Database (Denmark)

    Penkowa, Milena; Bohr, Adam; Nielsen, Allan

    2007-01-01

    and death, as seen in two rather contrasting pathological conditions: Neurodegeneration and neoplasms. MT-I+II have analogous functions including: 1) Antioxidant scavenging of reactive oxygen species (ROS); 2) Cytoprotection against degeneration and apoptosis; 3) Stimulation of cell growth and repair...... including angiogenesis/revascularization, activation of stem/progenitor cells, and neuroregeneration. Thereby, MT-I+II mediate neuroprotection, CNS restoration and clinical recovery during neurodegenerative disorders. Due to the promotion of cell survival, increased MT-I+II levels have been associated......-dependent transcription factors, protein synthesis, cellular energy levels/metabolism and cell redox state. Here, the neuroprotective and regenerative functions of MT-I+II are reviewed, and the presumed link to oncogenesis is critically perused....

  17. Sensitivity of neuroprogenitor cells to chemical-induced apoptosis using a multiplexed assay suitable for high-throughput screening

    International Nuclear Information System (INIS)

    Druwe, Ingrid; Freudenrich, Theresa M.; Wallace, Kathleen; Shafer, Timothy J.; Mundy, William R.

    2015-01-01

    High-throughput methods are useful for rapidly screening large numbers of chemicals for biological activity, including the perturbation of pathways that may lead to adverse cellular effects. In vitro assays for the key events of neurodevelopment, including apoptosis, may be used in a battery of tests for detecting chemicals that could result in developmental neurotoxicity. Apoptosis contributes to nervous system development by regulating the size of the neuroprogenitor cell pool, and the balance between cellular proliferation and apoptosis during neuroprogenitor cell proliferation helps to determine the size and shape of the nervous system. Therefore, chemicals that affect apoptosis during neuronal development can have deleterious effects on the developing brain. The present study examined the utility of a high-throughput assay to detect chemical-induced apoptosis in mouse or human neuroprogenitor cells, as well as differentiated human neurons derived from induced pluripotent stem cells. Apoptosis was assessed using an assay that measures enzymatic activity of caspase-3/7 in a rapid and cost efficient manner. The results show that all three commercially available models generated a robust source of proliferating neuroprogenitor cells, and that the assay was sensitive and reproducible when used in a multi-well plate format. There were differences in the response of rodent and human neuroprogenitor cells to a set of chemicals previously shown to induce apoptosis in vitro. Neuroprogenitor cells were more sensitive to chemical-induced apoptosis than differentiated neurons, suggesting that neuroprogenitor cells are one of the cell models that should be considered for use in a developmental neurotoxicity screening battery

  18. Brucella abortus-activated microglia induce neuronal death through primary phagocytosis.

    Science.gov (United States)

    Rodríguez, Ana M; Delpino, M Victoria; Miraglia, M Cruz; Costa Franco, Miriam M; Barrionuevo, Paula; Dennis, Vida A; Oliveira, Sergio C; Giambartolomei, Guillermo H

    2017-07-01

    Inflammation has long been implicated as a contributor to pathogenesis in neurobrucellosis. Many of the associated neurocognitive symptoms of neurobrucellosis may be the result of neuronal dysfunction resulting from the inflammatory response induced by Brucella abortus infection in the central nervous system. In this manuscript, we describe an immune mechanism for inflammatory activation of microglia that leads to neuronal death upon B. abortus infection. B. abortus was unable to infect or harm primary cultures of mouse neurons. However, when neurons were co-cultured with microglia and infected with B. abortus significant neuronal loss occurred. This phenomenon was dependent on TLR2 activation by Brucella lipoproteins. Neuronal death was not due to apoptosis, but it was dependent on the microglial release of nitric oxide (NO). B. abortus infection stimulated microglial proliferation, phagocytic activity and engulfment of neurons. NO secreted by B. abortus-activated microglia induced neuronal exposure of the "eat-me" signal phosphatidylserine (PS). Blocking of PS-binding to protein milk fat globule epidermal growth factor-8 (MFG-E8) or microglial vitronectin receptor-MFG-E8 interaction was sufficient to prevent neuronal loss by inhibiting microglial phagocytosis without affecting their activation. Taken together, our results indicate that B. abortus is not directly toxic to neurons; rather, these cells become distressed and are killed by phagocytosis in the inflammatory surroundings generated by infected microglia. Neuronal loss induced by B. abortus-activated microglia may explain, in part, the neurological deficits observed during neurobrucellosis. © 2017 Wiley Periodicals, Inc.

  19. Kappe neurons, a novel population of olfactory sensory neurons

    OpenAIRE

    Ahuja, Gaurav; Nia, Shahrzad Bozorg; Zapilko, Veronika; Shiriagin, Vladimir; Kowatschew, Daniel; Oka, Yuichiro; Korsching, Sigrun I.

    2014-01-01

    Perception of olfactory stimuli is mediated by distinct populations of olfactory sensory neurons, each with a characteristic set of morphological as well as functional parameters. Beyond two large populations of ciliated and microvillous neurons, a third population, crypt neurons, has been identified in teleost and cartilaginous fishes. We