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  1. Decay accelerating factor (CD55 protects neuronal cells from chemical hypoxia-induced injury

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    Tsokos George C

    2010-04-01

    Full Text Available Abstract Background Activated complement system is known to mediate neuroinflammation and neurodegeneration following exposure to hypoxic-ischemic insults. Therefore, inhibition of the complement activation cascade may represent a potential therapeutic strategy for the management of ischemic brain injury. Decay-accelerating factor (DAF, also known as CD55 inhibits complement activation by suppressing the function of C3/C5 convertases, thereby limiting local generation or deposition of C3a/C5a and membrane attack complex (MAC or C5b-9 production. The present study investigates the ability of DAF to protect primary cultured neuronal cells subjected to sodium cyanide (NaCN-induced hypoxia from degeneration and apoptosis. Methods Cultured primary cortical neurons from embryonic Sprague-Dawley rats were assigned one of four groups: control, DAF treatment alone, hypoxic, or hypoxic treated with DAF. Hypoxic cultures were exposed to NaCN for 1 hour, rinsed, followed by 24 hour exposure to 200 ng/ml of recombinant human DAF in normal medium. Human DAF was used in the present study and it has been shown to effectively regulate complement activation in rats. Neuronal cell function, morphology and viability were investigated by measuring plateau depolarization potential, counting the number dendritic spines, and observing TUNEL and MTT assays. Complement C3, C3a, C3a receptor (R production, C3a-C3aR interaction and MAC formation were assessed along with the generation of activated caspase-9, activated caspase-3, and activated Src. Results When compared to controls, hypoxic cells had fewer dendritic spines, reduced plateau depolarization accompanied by increased apoptotic activity and accumulation of MAC, as well as up-regulation of C3, C3a and C3aR, enhancement of C3a-C3aR engagement, and elevated caspase and Src activity. Treatment of hypoxic cells with 200 ng/ml of recombinant human DAF resulted in attenuation of neuronal apoptosis and exerted

  2. Inhibition of neuronal ferroptosis protects hemorrhagic brain

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    Li, Qian; Han, Xiaoning; Lan, Xi; Gao, Yufeng; Wan, Jieru; Durham, Frederick; Cheng, Tian; Yang, Jie; Wang, Zhongyu; Jiang, Chao; Ying, Mingyao; Stockwell, Brent R.

    2017-01-01

    Intracerebral hemorrhage (ICH) causes high mortality and morbidity, but our knowledge of post-ICH neuronal death and related mechanisms is limited. In this study, we first demonstrated that ferroptosis, a newly identified form of cell death, occurs in the collagenase-induced ICH model in mice. We found that administration of ferrostatin-1, a specific inhibitor of ferroptosis, prevented neuronal death and reduced iron deposition induced by hemoglobin in organotypic hippocampal slice cultures (OHSCs). Mice treated with ferrostatin-1 after ICH exhibited marked brain protection and improved neurologic function. Additionally, we found that ferrostatin-1 reduced lipid reactive oxygen species production and attenuated the increased expression level of PTGS2 and its gene product cyclooxygenase-2 ex vivo and in vivo. Moreover, ferrostatin-1 in combination with other inhibitors that target different forms of cell death prevented hemoglobin-induced cell death in OHSCs and human induced pluripotent stem cell–derived neurons better than any inhibitor alone. These results indicate that ferroptosis contributes to neuronal death after ICH, that administration of ferrostatin-1 protects hemorrhagic brain, and that cyclooxygenase-2 could be a biomarker of ferroptosis. The insights gained from this study will advance our knowledge of the post-ICH cell death cascade and be essential for future preclinical studies.

  3. Necrostatin-1 protection of dopaminergic neurons

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    Jing-ru Wu; Jie Wang; Sheng-kui Zhou; Long Yang; Jia-le Yin; Jun-ping Cao; Yan-bo Cheng

    2015-01-01

    Necroptosis is characterized by programmed necrotic cell death and autophagic activation and might be involved in the death process of dopaminergic neurons in Parkinson’s disease. We hypothesized that necrostatin-1 could block necroptosis and give protection to dopaminergic neurons. There is likely to be crosstalk between necroptosis and other cell death pathways, such as apoptosis and autophagy. PC12 cells were pretreated with necroststin-1 1 hour before expo-sure to 6-hydroxydopamine. We examined cell viability, mitochondrial membrane potential and expression patterns of apoptotic and necroptotic death signaling proteins. The results showed that the autophagy/lysosomal pathway is involved in the 6-hydroxydopamine-induced death pro-cess of PC12 cells. Mitochondrial disability induced overactive autophagy, increased cathepsin B expression, and diminished Bcl-2 expression. Necrostatin-1 within a certain concentration range (5–30 μM) elevated the viability of PC12 cells, stabilized mitochondrial membrane potential, inhibited excessive autophagy, reduced the expression of LC3-II and cathepsin B, and increased Bcl-2 expression. These findings suggest that necrostatin-1 exerted a protective effect against injury on dopaminergic neurons. Necrostatin-1 interacts with the apoptosis signaling pathway during this process. This pathway could be a new neuroprotective and therapeutic target in Par-kinson’s disease.

  4. Necrostatin-1 protection of dopaminergic neurons

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    Jing-ru Wu

    2015-01-01

    Full Text Available Necroptosis is characterized by programmed necrotic cell death and autophagic activation and might be involved in the death process of dopaminergic neurons in Parkinson′s disease. We hypothesized that necrostatin-1 could block necroptosis and give protection to dopaminergic neurons. There is likely to be crosstalk between necroptosis and other cell death pathways, such as apoptosis and autophagy. PC12 cells were pretreated with necroststin-1 1 hour before exposure to 6-hydroxydopamine. We examined cell viability, mitochondrial membrane potential and expression patterns of apoptotic and necroptotic death signaling proteins. The results showed that the autophagy/lysosomal pathway is involved in the 6-hydroxydopamine-induced death process of PC12 cells. Mitochondrial disability induced overactive autophagy, increased cathepsin B expression, and diminished Bcl-2 expression. Necrostatin-1 within a certain concentration range (5-30 μM elevated the viability of PC12 cells, stabilized mitochondrial membrane potential, inhibited excessive autophagy, reduced the expression of LC3-II and cathepsin B, and increased Bcl-2 expression. These findings suggest that necrostatin-1 exerted a protective effect against injury on dopaminergic neurons. Necrostatin-1 interacts with the apoptosis signaling pathway during this process. This pathway could be a new neuroprotective and therapeutic target in Parkinson′s disease.

  5. Necrostatin-1 protection of dopaminergic neurons

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    Wu, Jing-ru; Wang, Jie; Zhou, Sheng-kui; Yang, Long; Yin, Jia-le; Cao, Jun-ping; Cheng, Yan-bo

    2015-01-01

    Necroptosis is characterized by programmed necrotic cell death and autophagic activation and might be involved in the death process of dopaminergic neurons in Parkinson's disease. We hypothesized that necrostatin-1 could block necroptosis and give protection to dopaminergic neurons. There is likely to be crosstalk between necroptosis and other cell death pathways, such as apoptosis and autophagy. PC12 cells were pretreated with necroststin-1 1 hour before exposure to 6-hydroxydopamine. We examined cell viability, mitochondrial membrane potential and expression patterns of apoptotic and necroptotic death signaling proteins. The results showed that the autophagy/lysosomal pathway is involved in the 6-hydroxydopamine-induced death process of PC12 cells. Mitochondrial disability induced overactive autophagy, increased cathepsin B expression, and diminished Bcl-2 expression. Necrostatin-1 within a certain concentration range (5–30 μM) elevated the viability of PC12 cells, stabilized mitochondrial membrane potential, inhibited excessive autophagy, reduced the expression of LC3-II and cathepsin B, and increased Bcl-2 expression. These findings suggest that necrostatin-1 exerted a protective effect against injury on dopaminergic neurons. Necrostatin-1 interacts with the apoptosis signaling pathway during this process. This pathway could be a new neuroprotective and therapeutic target in Parkinson's disease. PMID:26330837

  6. Neuron Protective Constituents from Rheum Nanum and Rheum Sublanceolatum

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    XIANG Lan; LEI Fan; XING Dongming; WANG Wei; ZHENG Junhua

    2005-01-01

    The neuron protective activity of the chemical constituents from Rheum nanum and Rheum sublanceolatum in vitro was investigated using cultured embryonic mouse cortical cells exposed to oxygen-glucose deprivation. The protective effect was quantitatively evaluated by measuring the lactate dehydrogenase release rate. Most of the compounds reduce the lactate dehydrogenase release rate, including emodin, chrysophanol-8-O-β-D-glucopyranoside, 6-hydroxymusizin-8-O-β-D-glucopyranoside, gnetin C, torachrysone-8-O-β-D-glucopyranoside, and maesopsin, and all possess potent neuron protective activity. Chrysophanol and aloe-emodin exhibit neuron protection only at low concentrations. Emodin-8-O-β-D-glucopyranoside protects the neuron cells at high concentration. Aloe-emodin-8-O-β-D- glucopyranoside is inactive.

  7. Early and extensive CD55 loss from red blood cells supports a causal role in malarial anaemia

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    Gwamaka Moses

    2011-12-01

    Full Text Available Abstract Background Levels of complement regulatory proteins (CrP on the surface of red blood cells (RBC decrease during severe malarial anaemia and as part of cell ageing process. It remains unclear whether CrP changes seen during malaria contribute to the development of anaemia, or result from an altered RBC age distribution due to suppressive effects of malaria on erythropoiesis. Methods A cross sectional study was conducted in the north-east coast of Tanzania to investigate whether the changes in glycosylphosphatidylinositol (GPI-anchored complement regulatory proteins (CD55 and CD59 contributes to malaria anaemia. Blood samples were collected from a cohort of children under intensive surveillance for Plasmodium falciparum parasitaemia and illness. Levels of CD55 and CD59 were measured by flow cytometer and compared between anaemic (8.08 g/dl and non- anaemic children (11.42 g/dl. Results Levels of CD55 and CD59 decreased with increased RBC age. CD55 levels were lower in anaemic children and the difference was seen in RBC of all ages. Levels of CD59 were lower in anaemic children, but these differences were not significant. CD55, but not CD59, levels correlated positively with the level of haemoglobin in anaemic children. Conclusion The extent of CD55 loss from RBC of all ages early in the course of malarial anaemia and the correlation of CD55 with haemoglobin levels support the hypothesis that CD55 may play a causal role in this disorder.

  8. Role of CD97stalk and CD55 as molecular markers for prognosis and therapy of gastric carcinoma patients

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    LIU Yong; CHEN Li; PENG Shu-you; CHEN Zhou-xun; HOANG-VU C

    2005-01-01

    Objectives: To explore the mechanism of development and aggressiveness in gastric carcinomas by investigating the expression and role of CD97 and its cellular ligand CD55 in gastric carcinomas. Methods: Tumor and corresponding normal mucosal tissue, collected from 39 gastric carcinoma patients, were examined by immunohistochemistry and RT-PCR for the expression of CD97 and CD55. Results: CD97stalk was strongly stained on scattered tumor cells or small tumor cell clusters at the invasion front of gastric carcinomas. The expression of CD97stalk was frequently observed in tumors of stage Ⅰ and T1 gastric carcinoma patients. The expression of CD97stalk between Stage Ⅰ and Stage Ⅱ, Ⅲ, Ⅳ specimens showed significant difference (P<0.05), between T1 and T2, T3, T4 specimens also showed significant difference (P<0.05). Specimens with tumor invasion depth limited in mucosa of T 1 specimens showed higher positive CD55 expression than specimens with the same tumor invasion depth in T2, T3, T4 specimens, the expression of CD55 between T1 and T2, T3, T4 specimens was significantly different (P<0.05).There was strong correlation between the distribution patterns of CD97stalk and CD55 on tumor tissues (r=0.73, P<0.05). Signet ring cell carcinomas frequently contained strong CD97stalk and CD55-staining. Conclusions: Our results suggest that CD97stalk is probably involved in the growth, invasion and aggressiveness of gastric carcinomas by binding its cellular ligand CD55. CD97stalk and CD55 could be useful as molecular markers for prognosis and therapy of gastric carcinoma patients.

  9. Production of multiple transgenic Yucatan miniature pigs expressing human complement regulatory factors, human CD55, CD59, and H-transferase genes.

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    Young-Hee Jeong

    Full Text Available The present study was conducted to generate transgenic pigs coexpressing human CD55, CD59, and H-transferase (HT using an IRES-mediated polycistronic vector. The study focused on hyperacute rejection (HAR when considering clinical xenotransplantation as an alternative source for human organ transplants. In total, 35 transgenic cloned piglets were produced by somatic cell nuclear transfer (SCNT and were confirmed for genomic integration of the transgenes from umbilical cord samples by PCR analysis. Eighteen swine umbilical vein endothelial cells (SUVEC were isolated from umbilical cord veins freshly obtained from the piglets. We observed a higher expression of transgenes in the transgenic SUVEC (Tg SUVEC compared with the human umbilical vein endothelial cells (HUVEC. Among these genes, HT and hCD59 were expressed at a higher level in the tested Tg organs compared with non-Tg control organs, but there was no difference in hCD55 expression between them. The transgenes in various organs of the Tg clones revealed organ-specific and spatial expression patterns. Using from 0 to 50% human serum solutions, we performed human complement-mediated cytolysis assays. The results showed that, overall, the Tg SUVEC tested had greater survival rates than did the non-Tg SUVEC, and the Tg SUVEC with higher HT expression levels tended to have more down-regulated α-Gal epitope expression, resulting in greater protection against cytotoxicity. By contrast, several Tg SUVEC with low CD55 expression exhibited a decreased resistance response to cytolysis. These results indicated that the levels of HT expression were inversely correlated with the levels of α-Gal epitope expression and that the combined expression of hCD55, hCD59, and HT proteins in SUVECs markedly enhances a protective response to human serum-mediated cytolysis. Taken together, these results suggest that combining a polycistronic vector system with SCNT methods provides a fast and efficient alternative

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

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    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.

  11. Stearic acid protects primary cultured cortical neurons against oxidative stress

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    Ze-jian WANG; Cui-ling LIANG; Guang-mei LI; Cai-yi YU; Ming YIN

    2007-01-01

    Aim: To observe the effects of stearic acid against oxidative stress in primary cultured cortical neurons. Methods: Cortical neurons were exposed to glutamate,hydrogen peroxide (H202), or NaN3 insult in the presence or absence of stearic acid. Cell viability of cortical neurons was determined by MTT assay and LDH release. Endogenous antioxidant enzymes activity[superoxide dismutases (SOD),glutathione peroxidase (GSH-Px), and catalase (CAT)] and lipid peroxidation in cultured cortical neurons were evaluated using commercial kits. {3-[1(p-chloro-benzyl)-5-(isopropyl)-3-t-butylthiondol-2-yl]-2,2-dimethylpropanoic acid, Na}[MK886; 5 pmol/L; a noncompetitive inhibitor of proliferator-activated receptor(PPAR)α], bisphenol A diglycidyl ether (BADGE; 100 μmol/L; an antagonist of PPARγ), and cycloheximide (CHX; 30 μmol/L, an inhibitor of protein synthesis)were tested for their effects on the neuroprotection afforded by stearic acid.Western blotting was used to determine the PPARγ protein level in cortical neurons.Results: Stearic acid dose-dependently protected cortical neurons against glutamate or H202 injury and increased glutamate uptake in cultured neurons.This protection was concomitant to the inhibition of lipid peroxidation and to the promotion activity of Cu/Zn SOD and CAT in cultured cortical neurons. Its neuroprotective effects were completely blocked by BADGE and CHX. After incubation with H2O2 for 24 h, the expression of the PPARγ protein decreased significantly (P<0.05), and the inhibitory effect of H2O2 on the expression of PPARγ can be attenuated by stearic acid. Conclusion: Stearic acid can protect cortical neurons against oxidative stress by boosting the internal antioxidant enzymes.Its neuroprotective effect may be mainly mediated by the activation of PPARγ and new protein synthesis in cortical neurons.

  12. Engrailed Homeoprotein Protects Mesencephalic Dopaminergic Neurons from Oxidative Stress

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    Rekaik, Hocine; Blaudin de Thé, François-Xavier; Fuchs, Julia; Massiani-Beaudoin, Olivia; Prochiantz, Alain; Joshi, Rajiv L.

    2016-01-01

    Summary Engrailed homeoproteins are expressed in adult dopaminergic neurons of the substantia nigra. In Engrailed1 heterozygous mice, these neurons start dying at 6 weeks, are more sensitive to oxidative stress, and progressively develop traits similar to those observed following an acute and strong oxidative stress inflected to wild-type neurons. These changes include DNA strand breaks and the modification (intensity and distribution) of several nuclear and nucleolar heterochromatin marks. Engrailed1 and Engrailed2 are biochemically equivalent transducing proteins previously used to antagonize dopaminergic neuron death in Engrailed1 heterozygous mice and in mouse models of Parkinson disease. Accordingly, we show that, following an acute oxidative stress, a single Engrailed2 injection restores all nuclear and nucleolar heterochromatin marks, decreases the number of DNA strand breaks, and protects dopaminergic neurons against apoptosis. PMID:26411690

  13. Lipid raft disruption protects mature neurons against amyloid oligomer toxicity.

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    Malchiodi-Albedi, Fiorella; Contrusciere, Valentina; Raggi, Carla; Fecchi, Katia; Rainaldi, Gabriella; Paradisi, Silvia; Matteucci, Andrea; Santini, Maria Teresa; Sargiacomo, Massimo; Frank, Claudio; Gaudiano, Maria Cristina; Diociaiuti, Marco

    2010-04-01

    A specific neuronal vulnerability to amyloid protein toxicity may account for brain susceptibility to protein misfolding diseases. To investigate this issue, we compared the effects induced by oligomers from salmon calcitonin (sCTOs), a neurotoxic amyloid protein, on cells of different histogenesis: mature and immature primary hippocampal neurons, primary astrocytes, MG63 osteoblasts and NIH-3T3 fibroblasts. In mature neurons, sCTOs increased apoptosis and induced neuritic and synaptic damages similar to those caused by amyloid beta oligomers. Immature neurons and the other cell types showed no cytotoxicity. sCTOs caused cytosolic Ca(2+) rise in mature, but not in immature neurons and the other cell types. Comparison of plasma membrane lipid composition showed that mature neurons had the highest content in lipid rafts, suggesting a key role for them in neuronal vulnerability to sCTOs. Consistently, depletion in gangliosides protected against sCTO toxicity. We hypothesize that the high content in lipid rafts makes mature neurons especially vulnerable to amyloid proteins, as compared to other cell types; this may help explain why the brain is a target organ for amyloid-related diseases.

  14. Neuronal Sirt3 protects against excitotoxic injury in mouse cortical neuron culture.

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    Sun Hee Kim

    Full Text Available BACKGROUND: Sirtuins (Sirt, a family of nicotinamide adenine nucleotide (NAD dependent deacetylases, are implicated in energy metabolism and life span. Among the known Sirt isoforms (Sirt1-7, Sirt3 was identified as a stress responsive deacetylase recently shown to play a role in protecting cells under stress conditions. Here, we demonstrated the presence of Sirt3 in neurons, and characterized the role of Sirt3 in neuron survival under NMDA-induced excitotoxicity. METHODOLOGY/PRINCIPAL FINDINGS: To induce excitotoxic injury, we exposed primary cultured mouse cortical neurons to NMDA (30 µM. NMDA induced a rapid decrease of cytoplasmic NAD (but not mitochondrial NAD in neurons through poly (ADP-ribose polymerase-1 (PARP-1 activation. Mitochondrial Sirt3 was increased following PARP-1 mediated NAD depletion, which was reversed by either inhibition of PARP-1 or exogenous NAD. We found that massive reactive oxygen species (ROS produced under this NAD depleted condition mediated the increase in mitochondrial Sirt3. By transfecting primary neurons with a Sirt3 overexpressing plasmid or Sirt3 siRNA, we showed that Sirt3 is required for neuroprotection against excitotoxicity. CONCLUSIONS: This study demonstrated for the first time that mitochondrial Sirt3 acts as a prosurvival factor playing an essential role to protect neurons under excitotoxic injury.

  15. Increased deposition of C3b on red cells with low CR1 and CD55 in a malaria-endemic region of western Kenya: Implications for the development of severe anemia

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    Odera Michael M

    2008-08-01

    Full Text Available Abstract Background Severe anemia due to Plasmodium falciparum malaria is a major cause of mortality among young children in western Kenya. The factors that lead to the age-specific incidence of this anemia are unknown. Previous studies have shown an age-related expression of red cell complement regulatory proteins, which protect erythrocytes from autologous complement attack and destruction. Our primary objective was to determine whether in a malaria-endemic area red cells with low levels of complement regulatory proteins are at increased risk for complement (C3b deposition in vivo. Secondarily, we studied the relationship between red cell complement regulatory protein levels and hemoglobin levels. Methods Three hundred and forty-two life-long residents of a malaria-holoendemic region of western Kenya were enrolled in a cross-sectional study and stratified by age. We measured red cell C3b, CR1, CD55, and immune complex binding capacity by flow cytometry. Individuals who were positive for malaria were treated and blood was collected when they were free of parasitemia. Analysis of variance was used to identify independent variables associated with the %C3b-positive red cells and the hemoglobin level. Results Individuals between the ages of 6 and 36 months had the lowest red cell CR1, highest %C3b-positive red cells, and highest parasite density. Malaria prevalence also reached its peak within this age group. Among children ≤ 24 months of age the %C3b-positive red cells was usually higher in individuals who were treated for malaria than in uninfected individuals with similarly low red cell CR1 and CD55. The variables that most strongly influenced the %C3b-positive red cells were age, malaria status, and red cell CD55 level. Although it did not reach statistical significance, red cell CR1 was more important than red cell CD55 among individuals treated for malaria. The variables that most strongly influenced the hemoglobin level were age, the %C3b

  16. CD55 is a key complement regulatory protein that counteracts complement-mediated inactivation of Newcastle Disease Virus.

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    Rangaswamy, Udaya S; Cotter, Christopher R; Cheng, Xing; Jin, Hong; Chen, Zhongying

    2016-08-01

    Newcastle disease virus (NDV) is being developed as an oncolytic virus for virotherapy. In this study we analysed the regulation of complement-mediated inactivation of a recombinant NDV in different host cells. NDV grown in human cells was less sensitive to complement-mediated virus inactivation than NDV grown in embryonated chicken eggs. Additionally, NDV produced from HeLa-S3 cells is more resistant to complement than NDV from 293F cells, which correlated with higher expression and incorporation of complement regulatory proteins (CD46, CD55 and CD59) into virions from HeLa-S3 cells. Further analysis of the recombinant NDVs individually expressing the three CD molecules showed that CD55 is the most potent in counteracting complement-mediated virus inactivation. The results provide important information on selecting NDV manufacture substrate to mitigate complement-mediated virus inactivation.

  17. Iron accumulates in Huntington's disease neurons: protection by deferoxamine.

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    Jianfang Chen

    Full Text Available Huntington's disease (HD is a progressive neurodegenerative disorder caused by a polyglutamine-encoding CAG expansion in the huntingtin gene. Iron accumulates in the brains of HD patients and mouse disease models. However, the cellular and subcellular sites of iron accumulation, as well as significance to disease progression are not well understood. We used independent approaches to investigate the location of brain iron accumulation. In R6/2 HD mouse brain, synchotron x-ray fluorescence analysis revealed iron accumulation as discrete puncta in the perinuclear cytoplasm of striatal neurons. Further, perfusion Turnbull's staining for ferrous iron (II combined with transmission electron microscope ultra-structural analysis revealed increased staining in membrane bound peri-nuclear vesicles in R6/2 HD striatal neurons. Analysis of iron homeostatic proteins in R6/2 HD mice revealed decreased levels of the iron response proteins (IRPs 1 and 2 and accordingly decreased expression of iron uptake transferrin receptor (TfR and increased levels of neuronal iron export protein ferroportin (FPN. Finally, we show that intra-ventricular delivery of the iron chelator deferoxamine results in an improvement of the motor phenotype in R6/2 HD mice. Our data supports accumulation of redox-active ferrous iron in the endocytic / lysosomal compartment in mouse HD neurons. Expression changes of IRPs, TfR and FPN are consistent with a compensatory response to an increased intra-neuronal labile iron pool leading to increased susceptibility to iron-associated oxidative stress. These findings, together with protection by deferoxamine, support a potentiating role of neuronal iron accumulation in HD.

  18. Triggering of the dsRNA sensors TLR3, MDA5, and RIG-I induces CD55 expression in synovial fibroblasts.

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    Olga N Karpus

    Full Text Available BACKGROUND: CD55 (decay-accelerating factor is a complement-regulatory protein highly expressed on fibroblast-like synoviocytes (FLS. CD55 is also a ligand for CD97, an adhesion-type G protein-coupled receptor abundantly present on leukocytes. Little is known regarding the regulation of CD55 expression in FLS. METHODS: FLS isolated from arthritis patients were stimulated with pro-inflammatory cytokines and Toll-like receptor (TLR ligands. Transfection with polyinosinic-polycytidylic acid (poly(I:C and 5'-triphosphate RNA were used to activate the cytoplasmic double-stranded (dsRNA sensors melanoma differentiation-associated gene 5 (MDA5 and retinoic acid-inducible gene-I (RIG-I. CD55 expression, cell viability, and binding of CD97-loaded beads were quantified by flow cytometry. RESULTS: CD55 was expressed at equal levels on FLS isolated from patients with rheumatoid arthritis (RA, osteoarthritis, psoriatic arthritis and spondyloarthritis. CD55 expression in RA FLS was significantly induced by IL-1β and especially by the TLR3 ligand poly(I:C. Activation of MDA5 and RIG-I also enhanced CD55 expression. Notably, activation of MDA5 dose-dependently induced cell death, while triggering of TLR3 or RIG-I had a minor effect on viability. Upregulation of CD55 enhanced the binding capacity of FLS to CD97-loaded beads, which could be blocked by antibodies against CD55. CONCLUSIONS: Activation of dsRNA sensors enhances the expression of CD55 in cultured FLS, which increases the binding to CD97. Our findings suggest that dsRNA promotes the interaction between FLS and CD97-expressing leukocytes.

  19. Quinolinic acid induces disrupts cytoskeletal homeostasis in striatal neurons. Protective role of astrocyte-neuron interaction.

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    Pierozan, Paula; Ferreira, Fernanda; de Lima, Bárbara Ortiz; Pessoa-Pureur, Regina

    2015-02-01

    Quinolinic acid (QUIN) is an endogenous metabolite of the kynurenine pathway involved in several neurological disorders. Among the several mechanisms involved in QUIN-mediated toxicity, disruption of the cytoskeleton has been demonstrated in striatally injected rats and in striatal slices. The present work searched for the actions of QUIN in primary striatal neurons. Neurons exposed to 10 µM QUIN presented hyperphosphorylated neurofilament (NF) subunits (NFL, NFM, and NFH). Hyperphosphorylation was abrogated in the presence of protein kinase A and protein kinase C inhibitors H89 (20 μM) and staurosporine (10 nM), respectively, as well as by specific antagonists to N-methyl-D-aspartate (50 µM DL-AP5) and metabotropic glutamate receptor 1 (100 µM MPEP). Also, intra- and extracellular Ca(2+) chelators (10 µM BAPTA-AM and 1 mM EGTA, respectively) and Ca(2+) influx through L-type voltage-dependent Ca(2+) channel (10 µM verapamil) are implicated in QUIN-mediated effects. Cells immunostained for the neuronal markers βIII-tubulin and microtubule-associated protein 2 showed altered neurite/neuron ratios and neurite outgrowth. NF hyperphosphorylation and morphological alterations were totally prevented by conditioned medium from QUIN-treated astrocytes. Cocultured astrocytes and neurons interacted with one another reciprocally, protecting them against QUIN injury. Cocultured cells preserved their cytoskeletal organization and cell morphology together with unaltered activity of the phosphorylating system associated with the cytoskeleton. This article describes cytoskeletal disruption as one of the most relevant actions of QUIN toxicity in striatal neurons in culture with soluble factors secreted by astrocytes, with neuron-astrocyte interaction playing a role in neuroprotection.

  20. Prokineticin-2 upregulation during neuronal injury mediates a compensatory protective response against dopaminergic neuronal degeneration

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    Gordon, Richard; Neal, Matthew L.; Luo, Jie; Langley, Monica R.; Harischandra, Dilshan S.; Panicker, Nikhil; Charli, Adhithiya; Jin, Huajun; Anantharam, Vellareddy; Woodruff, Trent M.; Zhou, Qun-Yong; Kanthasamy, Anumantha G.; Kanthasamy, Arthi

    2016-01-01

    Prokineticin-2 (PK2), a recently discovered secreted protein, regulates important physiological functions including olfactory biogenesis and circadian rhythms in the CNS. Interestingly, although PK2 expression is low in the nigral system, its receptors are constitutively expressed on nigrostriatal neurons. Herein, we demonstrate that PK2 expression is highly induced in nigral dopaminergic neurons during early stages of degeneration in multiple models of Parkinson's disease (PD), including PK2 reporter mice and MitoPark mice. Functional studies demonstrate that PK2 promotes mitochondrial biogenesis and activates ERK and Akt survival signalling pathways, thereby driving neuroprotection. Importantly, PK2 overexpression is protective whereas PK2 receptor antagonism exacerbates dopaminergic degeneration in experimental PD. Furthermore, PK2 expression increased in surviving nigral dopaminergic neurons from PD brains, indicating that PK2 upregulation is clinically relevant to human PD. Collectively, our results identify a paradigm for compensatory neuroprotective PK2 signalling in nigral dopaminergic neurons that could have important therapeutic implications for PD. PMID:27703142

  1. Curcumin protects against staurosporine toxicity in rat neurons

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    Xiao-Yan Qin; Ji-Hui Lv; Jia Cui; Xue Fang; Yan Zhang

    2012-01-01

    Objective Curcumin is extracted from the turmeric plant (Curcuma longa Linn.) and is widely used as a food additive and traditional medicine.The present study investigated the activity of curcumin against staurosporine (STS) toxicity in cell culture.Methods Rat hippocampal neurons in primary culture were exposed to STS (20 μmol/L) and treated with curcumin (20 μmol/L).Cell viability was tested by MTT assay and reactive oxygen species (ROS) were measured using the MitoSOXTM red mitochondrial superoxide indicator.Western blot was used to assess changes in the levels of caspasc-3 (Csp3),heat shock protein 70 (Hsp70) and Akt.Results The results showed that curcumin protects against STS-induced cytotoxicity in rat hippocampal neurons.Csp3,Hsp70,Akt and ROS activation may be involved in this protection.Conclusion Curcumin could be a potential drug for combination with STS in cancer treatment to reduce the unwanted cytotoxicity of STS.

  2. Valproic acid protects neurons and promotes neuronal regeneration after brachial plexus avulsion****

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    Qiang Li; Dianxiu Wu; Rui Li; Xiaojuan Zhu; Shusen Cui

    2013-01-01

    Valproic acid has been shown to exert neuroprotective effects and promote neurite outgrowth in several peripheral nerve injury models. However, whether valproic acid can exert its beneficial effect on neurons after brachial plexus avulsion injury is currently unknown. In this study, brachial plexus root avulsion models, established in Wistar rats, were administered daily with valproic acid dis-solved in drinking water (300 mg/kg) or normal water. On days 1, 2, 3, 7, 14 and 28 after avulsion injury, tissues of the C 5-T 1 spinal cord segments of the avulsion injured side were harvested to in-vestigate the expression of Bcl-2, c-Jun and growth associated protein 43 by real-time PCR and western blot assay. Results showed that valproic acid significantly increased the expression of Bcl-2 and growth associated protein 43, and reduced the c-Jun expression after brachial plexus avulsion. Our findings indicate that valproic acid can protect neurons in the spinal cord and enhance neuronal regeneration fol owing brachial plexus root avulsion.

  3. The Expression and Action of Decay-Accelerating Factor (CD55 in Human Malignancies and Cancer Therapy

    Directory of Open Access Journals (Sweden)

    Jan-Henrik Mikesch

    2006-01-01

    Full Text Available Decay-accelerating factor (DAF, CD55 is physiologically acting as an inhibitor of the complement system, but is also broadly expressed in malignant tumours. Here DAF seems to exert different functions beyond its immunological role such as e.g. promotion of tumorigenesis, decrease of complement mediated tumor cell lysis, autocrine loops for cell rescue and evasion of apoptosis, neoangiogenesis, invasiveness, cell motility, and metastasis via oncogenic tyrosine kinase pathways and specific seven-span transmembrane receptors (CD97 binding. Therefore, DAF has already become a target for therapy. In this paper we review the role of DAF in human malignancies as described in different basic, diagnostic and experimental therapeutic studies.

  4. Protective effect of parvalbumin on excitotoxic motor neuron death

    DEFF Research Database (Denmark)

    Van den Bosch, L.; Schwaller, B.; Vleminckx, V.;

    2002-01-01

    Amyotrophic lateral sclerosis, ALS, AMPA receptor, calcium-binding proteins, calcium buffering, excitotoxity, kainic acid, motor neuron, parvalbumin......Amyotrophic lateral sclerosis, ALS, AMPA receptor, calcium-binding proteins, calcium buffering, excitotoxity, kainic acid, motor neuron, parvalbumin...

  5. Ginkgolides protects cultured cortical neurons against excitotoxic and oxidative insults

    Institute of Scientific and Technical Information of China (English)

    ZHANGYu-Yang; YUQing-Hai; YOUSong; SHENGLi

    2004-01-01

    AIM: The neurotoxicity of glutamate is associated with neurological disorders including hypoxic-ischaemic brain injury. Studies using cultured cortical neurons have demonstrated that exposure to glutamate produced delayed degeneration of mature neurons. Oxygen free radicals generated during injury have been postulated to be a major cause of neuronal cell

  6. Quantitation of CD55 and CD59 expression on reticulocytes and mature erythrocytes in paroxysmal nocturnal hemoglobinuria, aplastic anemia, and healthy control subjects.

    Science.gov (United States)

    Kim, Yeongsic; Lim, Jihyang; Kim, Myungshin; Kim, Yonggoo; Lee, Jong-Wook; Han, Kyungja

    2010-01-01

    Since PNH occasionally results in bone marrow failure, it is difficult to differentiate PNH from AA with small numbers of CD(55) (-)CD(59) (-) erythrocytes. We quantified CD55 and CD59 molecules expressed on normal reticulocytes and mature erythrocytes of paroxysmal nocturnal hemoglobinuria (PNH), aplastic anemia (AA), and normal individuals in order to determine their usefulness for differentiation between PNH and AA. A total of 56 patients (AA 39 patients, PNH 17 patients) and 10 healthy volunteers were enrolled. Two-color flow cytometric analyses were conducted using thiazole orange, anti-CD55 and CD59 monoclonal antibodies to identify CD(55) (-)CD(59) (-) reticulocytes and mature erythrocytes. Mean fluorescence level of CD(55) (+) mature erythrocytes was lowest in the PNH patients (13.2 x 10(3) MESF), and was significantly lower than in normal controls (16.7 x 10(3) MESF, p erythrocytes was lowest in the PNH subjects (24.5 x 10(3) MESF), significantly less than in normal controls (39.0 x 10(3) MESF, p erythrocytes may be useful in differentiating PNH from AA patients with small numbers of PNH-phenotype erythrocytes, and the total reticulocyte count may prove useful as a marker for PNH clone size.

  7. APP as a Protective Factor in Acute Neuronal Insults

    Science.gov (United States)

    Hefter, Dimitri; Draguhn, Andreas

    2017-01-01

    Despite its key role in the molecular pathology of Alzheimer’s disease (AD), the physiological function of amyloid precursor protein (APP) is unknown. Increasing evidence, however, points towards a neuroprotective role of this membrane protein in situations of metabolic stress. A key observation is the up-regulation of APP following acute (stroke, cardiac arrest) or chronic (cerebrovascular disease) hypoxic-ischemic conditions. While this mechanism may increase the risk or severity of AD, APP by itself or its soluble extracellular fragment APPsα can promote neuronal survival. Indeed, different animal models of acute hypoxia-ischemia, traumatic brain injury (TBI) and excitotoxicity have revealed protective effects of APP or APPsα. The underlying mechanisms involve APP-mediated regulation of calcium homeostasis via NMDA receptors (NMDAR), voltage-gated calcium channels (VGCC) or internal calcium stores. In addition, APP affects the expression of survival- or apoptosis-related genes as well as neurotrophic factors. In this review, we summarize the current understanding of the neuroprotective role of APP and APPsα and possible implications for future research and new therapeutic strategies. PMID:28210211

  8. Expression of membrane complement regulators, CD46, CD55 and CD59, in mesothelial cells of patients on peritoneal dialysis therapy.

    Science.gov (United States)

    Sei, Yumi; Mizuno, Masashi; Suzuki, Yasuhiro; Imai, Masaki; Higashide, Keiko; Harris, Claire L; Sakata, Fumiko; Iguchi, Daiki; Fujiwara, Michitaka; Kodera, Yasuhiro; Maruyama, Shoichi; Matsuo, Seiichi; Ito, Yasuhiko

    2015-06-01

    We investigated the expression of membrane complement regulators (CRegs), CD46, CD55 and CD59 in human mesothelial cells, and correlated with clinical background and level of complement (C) activation products in peritoneal dialysis (PD) fluids (PDF) to clarify influence of the C activation system in PD patients. Expression of CRegs was assessed on primary cultures of mesothelial cells (HPMC) harvested from PD fluid of 31 PD patients. Because expression of CD55 but not CD46 and CD59 in mesothelial cells was significantly correlated to value of dialysate-to-plasma creatinine concentration ratio (D/P Cre) (p<0.005) as an indicator of peritoneal function, we focused on analysis of CD55 expression of HPMCs in comparison with levels of C activation products in the PDF of the PD patients, and their background factors. When comparing expression of the CRegs between systemic neutrophils and HPMC, no correlation was observed, supporting that change of CRegs' expression in HPMC was independently occurring in the peritoneum. Expression of CD55 protein in HPMC was closely correlated with expression at the mRNA level (p<0.0001) and was inversely correlated with levels of sC5b-9 (p<0.05), but not C3, C4, IL6 and CA125 in the PDF. Complications of diabetes, usage of icodextrin and residual renal function were not correlated with change of CD55 expression in HPMCs. Our data show that the process of PD therapy modifies expression of CD55 on peritoneal mesothelium and triggers local C activation. These findings support efforts to modify PD therapy to limit effects on activation and regulation of the C system.

  9. Decreased expression of complement regulatory proteins, CD55 and CD59, on peripheral blood leucocytes in patients with type 2 diabetes and macrovascular diseases

    Institute of Scientific and Technical Information of China (English)

    MA Xi-wen; CHANG Zhi-wen; QIN Ming-zhao; SUN Ying; HUANG Hui-lian; HE Yan

    2009-01-01

    Background Macro- and microvascular diseases are the leading cause of morbidity and mortality in diabetic patients, but their mechanisms remain unclear. Recent reports provide evidence that the levels of CD55 and CD59 are decreased in diabetic microvascular diseases. However, very little is known about the levels of CD55 and CD59, the relationship between them and carotid artery intima-media thickness, and the effects of statins on CD55 and CD59 in diabetic macrovascular diseases.Methods The mean fluorescence intensity (MFI) of CD55 and CD59 expression on peripheral blood leucocyte subsets (lymphocytes, monocytes and neutrophils) was studied using flow cytometry, and carotid artery intima-media thickness was measured using B-mode ultrasonography in 23 healthy subjects (controls), 19 patients with type 2 diabetes (T2DM), and 43 patients with type 2 diabetes and macrovascular diseases (T2DM-M). The patients with T2DM-M were assigned to two subgroups based on whether statins were used: group with statins (n=23) and group without statins (n=20).Results Compared with the controls and T2DM, the MFI of CD55 positive neutrophils was significantly lower in T2DM-M (P=0.049 vs controls and P=0.033 vs T2DM); similarly, the MFI of CD59 positive monocytes was also lower in T2DM-M (P=0.038 vs controls and P=0.043 vs T2DM). The MFI of CD59 positive neutrophils in T2DM-M was lower than in T2DM (P=0.032). The levels of CD55 and CD59 were negatively associated with age and blood pressure (r=-0.245--0.352, P=0.041-0.003), but not acute-phase reactants and carotid artery intima-media thickness. The levels of CD55 and CD59 increased after treatment with statins, but the results were not significantly different (P >0.05).Conclusions CD55 and CD59 expressions on peripheral blood leucocytes are decreased in T2DM patients with macrovascular diseases. The results suggest that the decreased levels of complement regulatory proteins might play an important role in diabetic macrovascular

  10. Curcumin protects against interleukin-6-induced rapid Ca2+ influx in rat hippocampal neurons

    Institute of Scientific and Technical Information of China (English)

    Qinying Deng; Tao Huang; Hongmei Tang; Xingming Zhong; Sujian Xia; Xiangcai Wei; Jun Dong

    2011-01-01

    The current study sought to investigate the potential protective action of curcumin against interleukin-6-induced injury in rat hippocampal neurons. The results revealed that interleukin-6 induced typical cellular injury, such as the swelling of cell bodies and increased Ca2+ concentration. After administration of curcumin, interleukin-6-induced neurons recovered to a normal state, and the fluorescence intensity of Ca2+ gradually returned to normal. These findings suggest that curcumin exerts a protective effect on hippocampal neurons of rats. In addition, our results suggest that the protective effect of curcumin involves prevention of the rapid Ca2+ influx induced by interleukin-6, which maintains Ca2+ homeostasis.

  11. Recombinant AAV-mediated Expression of Human BDNF Protects Neurons against Cell Apoptosis in Aβ-induced Neuronal Damage Model

    Institute of Scientific and Technical Information of China (English)

    LIU Zhaohui; MA Dongliang; FENG Gaifeng; MA Yanbing; HU Haitao

    2007-01-01

    The human brain-derived neurotrophic factor (hBDNF) gene was cloned by polymerase chain reaction and the recombinant adeno-associated viral vector inserted with hBDNF gene (AAV-hBDNF) was constructed. Cultured rat hippocampal neurons were treated with Aβ25-35 and serued as the experimental Aβ-induced neuronal damage model (AD model), and the AD model was infected with AAV-hBDNF to explore neuroprotective effects of expression of BDNF. Cell viability was assayed by MTT. The expression of bcl-2 anti-apoptosis protein was detected by immunocytochemical staining. The change of intracellular free Ca ion ([Ca2+]i) was measured by laser scanning confocal microscopy. The results showed that BDNF had protective effects against Aβ-induced neuronal damage. The expression of the bcl-2 anti-apoptosis protein was raised significantly and the balance of [Ca2+]i was maintained in the AAV-hBDNF treatment group as compared with AD model group. These data suggested that recombinant AAV mediated a stable expression of hBDNF in cultured hippocampal neurons and resulted in significant neuron protective effects in AD model. The BDNF may reduce neuron apoptosis through increasing the expression of the bcl-2 anti-apoptosis protein and inhibiting intracellular calcium overload. The viral vector-mediated gene expression of BDNF may pave the way of a novel therapeutic strategy for the treatment of neurodegenerative diseases such as Alzheimer's disease.

  12. Naphthazarin protects against glutamate-induced neuronal death via activation of the Nrf2/ARE pathway

    Energy Technology Data Exchange (ETDEWEB)

    Son, Tae Gen; Kawamoto, Elisa M.; Yu, Qian-Sheng; Greig, Nigel H. [Laboratory of Neurosciences, National Institute on Aging, Intramural Research Program, 251 Bayview Blvd., Baltimore, MD 21224 (United States); Mattson, Mark P. [Laboratory of Neurosciences, National Institute on Aging, Intramural Research Program, 251 Bayview Blvd., Baltimore, MD 21224 (United States); Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD (United States); Camandola, Simonetta, E-mail: camandolasi@mail.nih.gov [Laboratory of Neurosciences, National Institute on Aging, Intramural Research Program, 251 Bayview Blvd., Baltimore, MD 21224 (United States)

    2013-04-19

    Highlights: •Naphthazarin activates the Nrf2/ARE pathway. •Naphthazarin induces Nrf2-driven genes in neurons and astrocytes. •Naphthazarin protects neurons against excitotoxicity. -- Abstract: Nuclear factor E2-related factor 2 (Nrf2)/antioxidant response element (ARE) pathway is an important cellular stress response pathway involved in neuroprotection. We previously screened several natural phytochemicals and identified plumbagin as a novel activator of the Nrf2/ARE pathway that can protect neurons against ischemic injury. Here we extended our studies to natural and synthetic derivatives of plumbagin. We found that 5,8-dimethoxy-1,4-naphthoquinone (naphthazarin) is a potent activator of the Nrf2/ARE pathway, up-regulates the expression of Nrf2-driven genes in primary neuronal and glial cultures, and protects neurons against glutamate-induced excitotoxicity.

  13. Protective effects of berberine against amyloid beta-induced toxicity in cultured rat cortical neurons

    Institute of Scientific and Technical Information of China (English)

    Jing Wang; Yanjun Zhang; Shuai Du; Mixia Zhang

    2011-01-01

    Berberine, a major constituent of Coptidis rhizoma, exhibits neural protective effects. The present study analyzed the potential protective effect of berberine against amyloid G-induced cytotoxicity in rat cerebral cortical neurons. Alzheimer's disease cell models were treated with 0.5 and 2 μmol/Lberberine for 36 hours to inhibit amyloid G-induced toxicity. Methyl thiazolyl tetrazolium assay and terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling staining results showed that berberine significantly increased cell viability and reduced cell apoptosis in primary cultured rat cortical neurons. In addition, western blot analysis revealed a protective effect of berberine against amyloid β-induced toxicity in cultured cortical neurons, which coincided with significantly decreased abnormal up-regulation of activated caspase-3. These results showed that berberine exhibited a protective effect against amyloid 13-induced cytotoxicity in cultured rat cortical neurons.

  14. Does Piroxicam really protect ischemic neurons and influence neuronal firing in cerebral ischemia? An exploration towards therapeutics.

    Science.gov (United States)

    Bhattacharya, Pallab; Pandey, Anand Kumar; Paul, Sudip; Patnaik, Ranjana

    2013-09-01

    Cerebral ischemia is still one of the most confusing and enigmatic neurological disorders with least understood injuries. The EEG measures have been traditionally used to detect residual neural dysfunctions after cerebral ischemia although having several shortcomings, yielding controversial and inconsistent results. It is feasible to hypothesize that advanced EEG research can overcome these shortcomings and provide more clear information regarding the long lasting neural impairment in the subjects suffered from brain stroke. To our understanding, EEG power spectrum density measures can significantly contribute towards intervening drug administered diseased model and give us correct status of neuronal firing after an insult. On the basis of our findings we hypothesize that Piroxicam, a non-steroidal anti-inflammatory drug (NSAID) can protect neurons and improves neuronal firing after ischemia/reperfusion injury in animal model of focal cerebral ischemia. This is the first ever finding which advocates the role of Piroxicam, a NSAID in neuronal firing apart from its other neuroprotective roles. Thus, we consider the possibility of modulation of neuronal firing as a therapeutic strategy to help prevent neuronal dysfunctions in cerebral ischemia.

  15. Is the loss of thalamostriatal neurons protective in parkinsonism?

    Science.gov (United States)

    Kusnoor, Sheila V; Muly, E Chris; Morgan, James I; Deutch, Ariel Y

    2009-12-01

    Neuronal loss in Parkinson's disease (PD) is more widespread than originally thought. Among the extrastriatal sites in which significant loss of neurons has been reported is the centremedian-parafascicular (CM-PF) complex of the thalamus, which provides one of the three major afferent sources to the striatum. The functional significance of CM-PF loss in PD is unclear. Interestingly, several recent small trials have suggested that deep brain stimulation of the CM-PF improves motor function in PD. We discuss the possible transsynaptic determination of CM-PF loss secondary to nigrostriatal dopamine degeneration, and suggest that expression of the glycoprotein cerebellin1 (Cbln1) in CM-PF neurons may play an important role in striatal synaptic remodeling in parkinsonism.

  16. Cholesterol synthesis inhibitors protect against platelet-activating factor-induced neuronal damage

    Directory of Open Access Journals (Sweden)

    Williams Alun

    2007-01-01

    Full Text Available Abstract Background Platelet-activating factor (PAF is implicated in the neuronal damage that accompanies ischemia, prion disease and Alzheimer's disease (AD. Since some epidemiological studies demonstrate that statins, drugs that reduce cholesterol synthesis, have a beneficial effect on mild AD, we examined the effects of two cholesterol synthesis inhibitors on neuronal responses to PAF. Methods Primary cortical neurons were treated with cholesterol synthesis inhibitors (simvastatin or squalestatin prior to incubation with different neurotoxins. The effects of these drugs on neuronal cholesterol levels and neuronal survival were measured. Immunoblots were used to determine the effects of simvastatin or squalestatin on the distribution of the PAF receptor and an enzyme linked immunoassay was used to quantify the amounts of PAF receptor. Results PAF killed primary neurons in a dose-dependent manner. Pre-treatment with simvastatin or squalestatin reduced neuronal cholesterol and increased the survival of PAF-treated neurons. Neuronal survival was increased 50% by 100 nM simvastatin, or 20 nM squalestatin. The addition of mevalonate restored cholesterol levels, and reversed the protective effect of simvastatin. Simvastatin or squalestatin did not affect the amounts of the PAF receptor but did cause it to disperse from within lipid rafts. Conclusion Treatment of neurons with cholesterol synthesis inhibitors including simvastatin and squalestatin protected neurons against PAF. Treatment caused a percentage of the PAF receptors to disperse from cholesterol-sensitive domains. These results raise the possibility that the effects of statins on neurodegenerative disease are, at least in part, due to desensitisation of neurons to PAF.

  17. Arctigenin protects against neuronal hearing loss by promoting neural stem cell survival and differentiation.

    Science.gov (United States)

    Huang, Xinghua; Chen, Mo; Ding, Yan; Wang, Qin

    2016-12-27

    Neuronal hearing loss has become a prevalent health problem. This study focused on the function of arctigenin (ARC) in promoting survival and neuronal differentiation of mouse cochlear neural stem cells (NSCs), and its protection against gentamicin (GMC) induced neuronal hearing loss. Mouse cochlea was used to isolate NSCs, which were subsequently cultured in vitro. The effects of ARC on NSC survival, neurosphere formation, differentiation of NSCs, neurite outgrowth, and neural excitability in neuronal network in vitro were examined. Mechanotransduction ability demonstrated by intact cochlea, auditory brainstem response (ABR), and distortion product optoacoustic emissions (DPOAE) amplitude in mice were measured to evaluate effects of ARC on GMC-induced neuronal hearing loss. ARC increased survival, neurosphere formation, neuron differentiation of NSCs in mouse cochlear in vitro. ARC also promoted the outgrowth of neurites, as well as neural excitability of the NSC-differentiated neuron culture. Additionally, ARC rescued mechanotransduction capacity, restored the threshold shifts of ABR and DPOAE in our GMC ototoxicity murine model. This study supports the potential therapeutic role of ARC in promoting both NSCs proliferation and differentiation in vitro to functional neurons, thus supporting its protective function in the therapeutic treatment of neuropathic hearing loss in vivo.

  18. O papel das proteínas reguladoras do complemento CD55/CD59 em células de sangue periférico de pacientes com lúpus eritematoso sistêmico The role of CD55/CD59 complement regulatory proteins on peripheral blood cells of systemic lupus erythematosus patients

    Directory of Open Access Journals (Sweden)

    Ana Paula Alegretti

    2009-06-01

    Full Text Available CD55 e CD59 são proteínas de membrana ancoradas por glicosilfosfatidilinositol que apresentam propriedades reguladoras da ativação da cascata do complemento. Essa regulação ocorre através da inibição da C3 convertase pelo CD55 e prevenção da etapa final de polimerização do complexo de ataque à membrana pelo CD59. Deficiência na expressão dessas proteínas pode estar associada a uma maior ativação do sistema complemento, inclusive do complexo de ataque à membrana, levando à morte celular. Pacientes com lúpus eritematoso sistêmico, com anemia hemolítica e linfopenia, parecem apresentar uma deficiência adquirida de CD55 e CD59. Contudo, os mecanismos que modulam essa diminuída expressão continuam desconhecidos e o seu impacto nas manifestações do lúpus eritematoso sistêmico precisa ser mais bem estudado.CD55 and CD59 are glycosylphosphatidylinositol-anchored proteins with regulatory properties on the activating cascades of the complement system. This regulation occurs through inhibition of the C3-convertase formation by CD55, and prevention of the terminal polymerization of the membrane attack complex by CD59. Deficiency in the expression of these proteins can be associated with increased susceptibility to complement-mediated cell death. Systemic lupus erythematosus patients with hemolytic anemia and lymphopenia seem to have an acquired deficiency of CD55 and CD59 proteins. However, the mechanisms involved in this deficiency and its impact on the clinical manifestation of SLE needs to be further investigated.

  19. Orexins protect neuronal cell cultures against hypoxic stress: an involvement of Akt signaling.

    Science.gov (United States)

    Sokołowska, Paulina; Urbańska, Anna; Biegańska, Kaja; Wagner, Waldemar; Ciszewski, Wojciech; Namiecińska, Magdalena; Zawilska, Jolanta B

    2014-01-01

    Orexins A and B are peptides produced mainly by hypothalamic neurons that project to numerous brain structures. We have previously demonstrated that rat cortical neurons express both types of orexin receptors, and their activation by orexins initiates different intracellular signals. The present study aimed to determine the effect of orexins on the Akt kinase activation in the rat neuronal cultures and the significance of that response in neurons subjected to hypoxic stress. We report the first evidence that orexins A and B stimulated Akt in cortical neurons in a concentration- and time-dependent manner. Orexin B more potently than orexin A increased Akt phosphorylation, but the maximal effect of both peptides on the kinase activation was very similar. Next, cultured cortical neurons were challenged with cobalt chloride, an inducer of reactive oxygen species and hypoxia-mediated signaling pathways. Under conditions of chemical hypoxia, orexins potently increased neuronal viability and protected cortical neurons against oxidative stress. Our results also indicate that Akt kinase plays an important role in the pro-survival effects of orexins in neurons, which implies a possible mechanism of the orexin-induced neuroprotection.

  20. Protective Effect of Interleukin-1β on Motor Neurons after Sciatic Nerve Injury in Rats

    Institute of Scientific and Technical Information of China (English)

    翁雨雄; 巴拉特; 洪光祥; 王发斌; 陈振斌; 黄启顺

    2004-01-01

    Summary: Protective effect of interleukin-lβ (IL-1β) on motor neurons was studied after peripheral nerve injury. Twenty Wistar rats were divided into 2 groups randomly. The right sciatic nerve of each rat was resected. After silicon tubulization of sciatic nerve in rat, 15 μl 1 ng/ml IL-1β and PBS solution were injected into the silicon capsule respectively. Enzyme histochemistry was performed to show acetyle cholesterase (AchE) and nitric oxide staining (NOS) activity of spinal a motor neurons in spinal segments 2 weeks later. Neurons were counted and the diameter and cross sectional (c/s) area of neurons were analyzed by using computer image analysis system. The results showed that as compared with the normal side, both enzyme activities significantly changed in motor neurons in PBS group. The diameter and c/s area of both neurons changed significantly too (P<0.01). These results suggest that exogenous IL-1β protects a-motor neurons from degeneration and necrosis after peripheral nerve injury.

  1. Neuro-protective effects of CNTF on hippocampal neurons via an unknown signal transduction pathway

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    In our previous study, we proposed that there may be an unknown pathway in the upper stream of the known signal transduction pathway of Ciliary neurotrophic factor (CNTF) that mediates the neuro-protective function of CNTF. In the present experiment, we observed that the neuro-protective function of the non-classic signal transduction pathway in a L-NMDA (a glutamic acid ion type receptor atagonist) induced hippocampal neuron injury model, using primary culture rat hippocampal neurons, continuous photography and gp130 immunohistochemical assay. The results showed that L-NMDA induced injurious reaction of hippocampal neurons, and CNTF was able to inhibit the toxic action of L-NMDA on hippocampal neurons. Additionally, when JAK/STATs in the known classic signal transduction pathway of CNTF were blocked by PTPi-2, the protective effect of CNTF against L-NMDA injury still existed. L-NMDA caused a rapid increase in the concentration of hippocampal intracellular free [Ca2+]i. CNTF was able to attenuate L-NMDA-induced elevation of [Ca2+]i, and blocking JAK/STATs in the known classic signal trans- duction pathway of CNTF did not affect L-NMDA- induced elevation of [Ca2+]i, indicating that, apart from the known classic signal transduction pathway, there may be some other transduction pathways for CNTF to exert the protective effect on hippocampal neurons, and this pathway is related to [Ca2+].

  2. Bimatoprost protects retinal neuronal damage via Akt pathway.

    Science.gov (United States)

    Takano, Norihito; Tsuruma, Kazuhiro; Ohno, Yuta; Shimazawa, Masamitsu; Hara, Hideaki

    2013-02-28

    Worldwide, prostaglandin analogs, such as bimatoprost, have become the major therapeutic class for medical treatment of glaucoma because of their efficacy and generally well tolerated systemic safety profile. However, the detailed mechanism of the direct action of bimatoprost on retinal ganglion cells (RGC) has rarely been understood. Thus, in this study, we elucidated the mechanism of the protective effects of bimatoprost on RGC against oxidative stress. To examine the protective effects of bimatoprost, cultured RGC with various concentrations of bimatoprost (in both free acid and amide form) were exposed to l-buthionin-(S,R)-sulfoximine (BSO) plus glutamate or serum depletion in vitro and intravitreal injection of N-methyl-D-aspartate (NMDA) was used to induce retinal damage in vivo. To elucidate the protective mechanism of bimatoprost, we used western blot analysis to investigate the phosphorylation of Akt and extracellular signal-regulated kinase (ERK). Bimatoprost significantly reduced BSO plus glutamate- and serum deprivation-induced death in concentration-dependent manners. Bimatoprost induced activation of Akt and ERK, and a phosphatidylinositol 3-kinase inhibitor, LY294002, attenuated the protective effect of bimatoprost. On the other hand, a mitogen-activated protein kinase kinase inhibitor, U0126, exhibited protective effect unexpectedly. Moreover, ERK was more phosphorylated by attenuation of Akt activity in cultured RGC. In an in vivo study, bimatoprost reduced NMDA-induced RGC death. Taken together, these findings indicate that bimatoprost has protective effects on in vitro and in vivo retinal damage, suggesting that the mechanism underlying may be via the Akt pathway, which may modulate the ERK pathway.

  3. Ginseng Rb fraction protects glia, neurons and cognitive function in a rat model of neurodegeneration.

    Science.gov (United States)

    Xu, Kangning; Zhang, Yufen; Wang, Yan; Ling, Peng; Xie, Xin; Jiang, Chenyao; Zhang, Zhizhen; Lian, Xiao-Yuan

    2014-01-01

    The loss and injury of neurons play an important role in the onset of various neurodegenerative diseases, while both microgliosis and astrocyte loss or dysfunction are significant causes of neuronal degeneration. Previous studies have suggested that an extract enriched panaxadiol saponins from ginseng has more neuroprotective potential than the total saponins of ginseng. The present study investigated whether a fraction of highly purified panaxadiol saponins (termed as Rb fraction) was protective for both glia and neurons, especially GABAergic interneurons, against kainic acid (KA)-induced excitotoxicity in rats. Rats received Rb fraction at 30 mg/kg (i.p.), 40 mg/kg (i.p. or saline followed 40 min later by an intracerebroventricular injection of KA. Acute hippocampal injury was determined at 48 h after KA, and impairment of hippocampus-dependent learning and memory as well as delayed neuronal injury was determined 16 to 21 days later. KA injection produced significant acute hippocampal injuries, including GAD67-positive GABAergic interneuron loss in CA1, paralbumin (PV)-positive GABAergic interneuron loss, pyramidal neuron degeneration and astrocyte damage accompanied with reactive microglia in both CA1 and CA3 regions of the hippocampus. There was also a delayed loss of GAD67-positive interneurons in CA1, CA3, hilus and dentate gyrus. Microgliosis also became more severe 21 days later. Accordingly, KA injection resulted in hippocampus-dependent spatial memory impairment. Interestingly, the pretreatment with Rb fraction at 30 or 40 mg/kg significantly protected the pyramidal neurons and GABAergic interneurons against KA-induced acute excitotoxicity and delayed injury. Rb fraction also prevented memory impairments and protected astrocytes from KA-induced acute excitotoxicity. Additionally, microglial activation, especially the delayed microgliosis, was inhibited by Rb fraction. Overall, this study demonstrated that Rb fraction protected both astrocytes and neurons

  4. Ginseng Rb fraction protects glia, neurons and cognitive function in a rat model of neurodegeneration.

    Directory of Open Access Journals (Sweden)

    Kangning Xu

    Full Text Available The loss and injury of neurons play an important role in the onset of various neurodegenerative diseases, while both microgliosis and astrocyte loss or dysfunction are significant causes of neuronal degeneration. Previous studies have suggested that an extract enriched panaxadiol saponins from ginseng has more neuroprotective potential than the total saponins of ginseng. The present study investigated whether a fraction of highly purified panaxadiol saponins (termed as Rb fraction was protective for both glia and neurons, especially GABAergic interneurons, against kainic acid (KA-induced excitotoxicity in rats. Rats received Rb fraction at 30 mg/kg (i.p., 40 mg/kg (i.p. or saline followed 40 min later by an intracerebroventricular injection of KA. Acute hippocampal injury was determined at 48 h after KA, and impairment of hippocampus-dependent learning and memory as well as delayed neuronal injury was determined 16 to 21 days later. KA injection produced significant acute hippocampal injuries, including GAD67-positive GABAergic interneuron loss in CA1, paralbumin (PV-positive GABAergic interneuron loss, pyramidal neuron degeneration and astrocyte damage accompanied with reactive microglia in both CA1 and CA3 regions of the hippocampus. There was also a delayed loss of GAD67-positive interneurons in CA1, CA3, hilus and dentate gyrus. Microgliosis also became more severe 21 days later. Accordingly, KA injection resulted in hippocampus-dependent spatial memory impairment. Interestingly, the pretreatment with Rb fraction at 30 or 40 mg/kg significantly protected the pyramidal neurons and GABAergic interneurons against KA-induced acute excitotoxicity and delayed injury. Rb fraction also prevented memory impairments and protected astrocytes from KA-induced acute excitotoxicity. Additionally, microglial activation, especially the delayed microgliosis, was inhibited by Rb fraction. Overall, this study demonstrated that Rb fraction protected both

  5. Investigation of several influential factors on flow cytometry analysis of CD55 and CD59 expression on red blood cells%红细胞CD55、CD59流式细胞术检测方法的若干影响因素探讨

    Institute of Scientific and Technical Information of China (English)

    张薇薇; 张军; 方超平; 沈茜

    2011-01-01

    Objective To study some factors that may influence the measurements of CD55 and CD59 expression on red blood cells by flow cytometry and establish the standard operation procedure. Methods Ethylene diamine tetraacetic acid( EDTA )-anticoagulated peripheral bloods from 15 patients with non-hematological disorder and 11 patients with paroxysmal nocturnal hemoglobinuria ( PNH ) were determined for CD55 and CD59 expression on red blood cells by flow cytometry. The various amounts of monoclonal antibody ( mAb ), the fluorescein type that conjugated with mAb and the staining time were analyzed. Results The mean fluorescence intensity ( MFI ) increased with the increasing amount of mAb before the saturated amount of mAb ( < 9 jjlL ) were added. The positive rates and MFI from using anti-CD55 labeled with fluorescein isothiocyanate ( FITC ) were lower than those from anti-CD55-phycoerythrin ( PE ). There was no statistical significance in CD59 positive rate between FITC and PE, while the higher MFI was observed significantly using anti-CD59-FITC. The staining time had a significant impact on not only the positive rate of CD55-PE but also the MFI obtained from CD59-FITC and CD55-PE ( P <0. 05 ), except the CD59-FITC positive rate between the 2 groups with 3 h. Conclusions The flow cytometry analysis of CD55 and CD59 expression on red blood cells is strongly influenced by the mAb amount, the mAb's fluorescein type and staining time. To ensure a proper reaction and a reliable result, we recommend a two-color staining method of anti-CD59-FITC and anti-CD55-PE, red blood cells in the range from 1.6 X 105 to 2. 8 X 105 stained with 12 jxL of each mAb and an incubation time of 40 min.%目的 探讨流式细胞仪测定红细胞表面CD55、CD59试验过程中影响检测的若干因素,建立此项目的 标准操作程序.方法 利用流式细胞仪对15例非血液病、11例阵发性血红蛋白尿症(PNH)的乙二胺四乙酸(EDTA)外周抗凝血进行红细胞CD55、CD59

  6. Synthesis of docosahexaenoic acid from eicosapentaenoic acid in retina neurons protects photoreceptors from oxidative stress.

    Science.gov (United States)

    Simón, María Victoria; Agnolazza, Daniela L; German, Olga Lorena; Garelli, Andrés; Politi, Luis E; Agbaga, Martin-Paul; Anderson, Robert E; Rotstein, Nora P

    2016-03-01

    Oxidative stress is involved in activating photoreceptor death in several retinal degenerations. Docosahexaenoic acid (DHA), the major polyunsaturated fatty acid in the retina, protects cultured retina photoreceptors from apoptosis induced by oxidative stress and promotes photoreceptor differentiation. Here, we investigated whether eicosapentaenoic acid (EPA), a metabolic precursor to DHA, had similar effects and whether retinal neurons could metabolize EPA to DHA. Adding EPA to rat retina neuronal cultures increased opsin expression and protected photoreceptors from apoptosis induced by the oxidants paraquat and hydrogen peroxide (H2 O2 ). Palmitic, oleic, and arachidonic acids had no protective effect, showing the specificity for DHA. We found that EPA supplementation significantly increased DHA percentage in retinal neurons, but not EPA percentage. Photoreceptors and glial cells expressed Δ6 desaturase (FADS2), which introduces the last double bond in DHA biosynthetic pathway. Pre-treatment of neuronal cultures with CP-24879 hydrochloride, a Δ5/Δ6 desaturase inhibitor, prevented EPA-induced increase in DHA percentage and completely blocked EPA protection and its effect on photoreceptor differentiation. These results suggest that EPA promoted photoreceptor differentiation and rescued photoreceptors from oxidative stress-induced apoptosis through its elongation and desaturation to DHA. Our data show, for the first time, that isolated retinal neurons can synthesize DHA in culture. Docosahexaenoic acid (DHA), the major polyunsaturated fatty acid in retina photoreceptors, and its precursor, eicosapentaenoic acid (EPA) have multiple beneficial effects. Here, we show that retina neurons in vitro express the desaturase FADS2 and can synthesize DHA from EPA. Moreover, addition of EPA to these cultures protects photoreceptors from oxidative stress and promotes their differentiation through its metabolization to DHA.

  7. Clinacanthus nutans Protects Cortical Neurons Against Hypoxia-Induced Toxicity by Downregulating HDAC1/6.

    Science.gov (United States)

    Tsai, Hsin-Da; Wu, Jui-Sheng; Kao, Mei-Han; Chen, Jin-Jer; Sun, Grace Y; Ong, Wei-Yi; Lin, Teng-Nan

    2016-09-01

    Many population-based epidemiological studies have unveiled an inverse correlation between intake of herbal plants and incidence of stroke. C. nutans is a traditional herbal medicine widely used for snake bite, viral infection and cancer in Asian countries. However, its role in protecting stroke damage remains to be studied. Despite of growing evidence to support epigenetic regulation in the pathogenesis and recovery of stroke, a clear understanding of the underlying molecular mechanisms is still lacking. In the present study, primary cortical neurons were subjected to in vitro oxygen-glucose deprivation (OGD)-reoxygenation and hypoxic neuronal death was used to investigate the interaction between C. nutans and histone deacetylases (HDACs). Using pharmacological agents (HDAC inhibitor/activator), loss-of-function (HDAC siRNA) and gain-of-function (HDAC plasmid) approaches, we demonstrated an early induction of HDAC1/2/3/8 and HDAC6 in neurons after OGD insult. C. nutans extract selectively inhibited HDAC1 and HDAC6 expression and attenuated neuronal death. Results of reporter analysis further revealed that C. nutans suppressed HDAC1 and HDAC6 transcription. Besides ameliorating neuronal death, C. nutans also protected astrocytes and endothelial cells from hypoxic-induced cell death. In summary, results support ability for C. nutans to suppress post-hypoxic HDACs activation and mitigate against OGD-induced neuronal death. This study further opens a new avenue for the use of herbal medicines to regulate epigenetic control of brain injury.

  8. Neuropeptide Y protects cerebral cortical neurons by regulating microglial immune function

    Institute of Scientific and Technical Information of China (English)

    Qijun Li; Changzheng Dong; Wenling Li; Wei Bu; Jiang Wu; Wenqing Zhao

    2014-01-01

    Neuropeptide Y has been shown to inhibit the immunological activity of reactive microglia in the rat cerebral cortex, to reduce N-methyl-D-aspartate current (INMDA) in cortical neurons, and protect neurons. In this study, after primary cultured microglia from the cerebral cortex of rats were treated with lipopolysaccharide, interleukin-1β and tumor necrosis factor-α levels in the cell culture medium increased, and mRNA expression of these cytokines also increased. After primary cultured cortical neurons were incubated with the lipopolysaccharide-treated microg-lial conditioned medium, peak INMDA in neurons increased. These effects of lipopolysaccharide were suppressed by neuropeptide Y. After addition of the neuropeptide Y Y1 receptor antago-nist BIBP3226, the effects of neuropeptide Y completely disappeared. These results suggest that neuropeptide Y prevents excessive production of interleukin-1β and tumor necrosis factor-α by inhibiting microglial reactivity. This reduces INMDA in rat cortical neurons, preventing excitotoxic-ity, thereby protecting neurons.

  9. Oenanthe Javanica Extract Protects Against Experimentally Induced Ischemic Neuronal Damage via its Antioxidant Effects

    Directory of Open Access Journals (Sweden)

    Joon Ha Park

    2015-01-01

    Full Text Available Background: Water dropwort (Oenanthe javanica as a popular traditional medicine in Asia shows various biological properties including antioxidant activity. In this study, we firstly examined the neuroprotective effect of Oenanthe javanica extract (OJE in the hippocampal cornus ammonis 1 region (CA1 region of the gerbil subjected to transient cerebral ischemia. Methods: Gerbils were established by the occlusion of common carotid arteries for 5 min. The neuroprotective effect of OJE was estimated by cresyl violet staining. In addition, 4 antioxidants (copper, zinc superoxide dismutase [SOD], manganese SOD, catalase, and glutathione peroxidase immunoreactivities were investigated by immunohistochemistry. Results: Pyramidal neurons in the CA1 region showed neuronal death at 5 days postischemia; at this point in time, all antioxidants immunoreactivities disappeared in CA1 pyramidal neurons and showed in many nonpyramidal cells. Treatment with 200 mg/kg, not 100 mg/kg, OJE protected CA1 pyramidal neurons from ischemic damage. In addition, 200 mg/kg OJE treatment increased or maintained antioxidants immunoreactivities. Especially, among the antioxidants, glutathione peroxidase immunoreactivity was effectively increased in the CA1 pyramidal neurons of the OJE-treated sham-operated and ischemia-operated groups. Conclusion: Our present results indicate that treatment with OJE can protect neurons from transient ischemic damage and that the neuroprotective effect may be closely associated with increased or maintained intracellular antioxidant enzymes by OJE.

  10. Oenanthe Javanica Extract Protects Against Experimentally Induced Ischemic Neuronal Damage via its Antioxidant Effects

    Institute of Scientific and Technical Information of China (English)

    Joon Ha Park; Jeong Hwi Cho; In Hye Kim; Ji Hyeon Ahn; Jae-Chul Lee; Bai Hui Chen; Bich-Na Shin

    2015-01-01

    Background:Water dropwort (Oenanthejavanica) as a popular traditional medicine in Asia shows various biological properties including antioxidant activity.In this study,we firstly examined the neuroprotective effect of Oenanthejavanica extract (OJE) in the hippocampal cornus ammonis 1 region (CA1 region) of the gerbil subjected to transient cerebral ischemia.Methods:Gerbils were established by the occlusion of common carotid arteries for 5 min.The neuroprotective effect of OJE was estimated by cresyl violet staining.In addition,4 antioxidants (copper,zinc superoxide dismutase [SOD],manganese SOD,catalase,and glutathione peroxidase) immunoreactivities were investigated by immunohistochemistry.Results:Pyramidal neurons in the CA1 region showed neuronal death at 5 days postischemia;at this point in time,all antioxidants immunoreactivities disappeared in CA1 pyramidal neurons and showed in many nonpyramidal cells.Treatment with 200 mg/kg,not 100 mg/kg,OJE protected CA1 pyramidal neurons from ischemic damage.In addition,200 mg/kg OJE treatment increased or maintained antioxidants immunoreactivities.Especially,among the antioxidants,glutathione peroxidase immunoreactivity was effectively increased in the CA1 pyramidal neurons of the OJE-treated sham-operated and ischemia-operated groups.Conclusion:Our present results indicate that treatment with OJE can protect neurons from transient ischemic damage and that the neuroprotective effect may be closely associated with increased or maintained intracellular antioxidant enzymes by OJE.

  11. Parkin protects dopaminergic neurons from excessive Wnt/{beta}-catenin signaling

    Energy Technology Data Exchange (ETDEWEB)

    Rawal, Nina [Laboratory of Molecular Neurobiology, MBB, DBRM, Karolinska Institute, S-17177 Stockholm (Sweden); Corti, Olga [Universite Pierre et Marie Curie-Paris 6, CRICM UMR-S975, Inserm, U975 (France); CNRS, UMR 7225, Paris (France); Sacchetti, Paola [Laboratory of Molecular Neurobiology, MBB, DBRM, Karolinska Institute, S-17177 Stockholm (Sweden); Ardilla-Osorio, Hector [Universite Pierre et Marie Curie-Paris 6, CRICM UMR-S975, Inserm, U975 (France); CNRS, UMR 7225, Paris (France); Sehat, Bita [Cancer Center Karolinska, Karolinska Institute, S-17177 Stockholm (Sweden); Brice, Alexis [Universite Pierre et Marie Curie-Paris 6, CRICM UMR-S975, Inserm, U975 (France); CNRS, UMR 7225, Paris (France); Department of Genetics and Cytogenetics, AP-HP, Groupe Hospitalier Pitie-Salpetriere, Paris (France); Arenas, Ernest, E-mail: Ernest.Arenas@ki.se [Laboratory of Molecular Neurobiology, MBB, DBRM, Karolinska Institute, S-17177 Stockholm (Sweden)

    2009-10-23

    Parkinson's disease (PD) is caused by degeneration of the dopaminergic (DA) neurons of the substantia nigra but the molecular mechanisms underlying the degenerative process remain elusive. Several reports suggest that cell cycle deregulation in post-mitotic neurons could lead to neuronal cell death. We now show that Parkin, an E3 ubiquitin ligase linked to familial PD, regulates {beta}-catenin protein levels in vivo. Stabilization of {beta}-catenin in differentiated primary ventral midbrain neurons results in increased levels of cyclin E and proliferation, followed by increased levels of cleaved PARP and loss of DA neurons. Wnt3a signaling also causes death of post-mitotic DA neurons in parkin null animals, suggesting that both increased stabilization and decreased degradation of {beta}-catenin results in DA cell death. These findings demonstrate a novel regulation of Wnt signaling by Parkin and suggest that Parkin protects DA neurons against excessive Wnt signaling and {beta}-catenin-induced cell death.

  12. Protective effect of astrocyte-conditioned medium on neurons following hypoxia and mechanical injury

    Directory of Open Access Journals (Sweden)

    YAN Ji-wen

    2013-02-01

    Full Text Available 【Abstract】Objective: To investigate the protec-tive effect of mouse astrocyte-conditioned medium (ACM on hypoxic and mechanically injured neurons by a cell model in vitro, and to explore the possible mechanism. Methods: The model of hypoxic neuronal injury was caused by 3% O 2 in three-gas incubator. Neurons were cul-tured with ordinary medium or 20% ACM respectively and randomly divided into hypoxic group (hypoxia for 4, 8, 24 h and marked as H4R0, H8R0, H24R0 and hypoxia reoxygenation group (H4R24, H8R24, H24R24. Mechanical injury model was developed by scratching neurons cultured in 20% ACM or ordinary medium to different degrees. Neu-rons in both medium were divided into normal control group, mild, moderate and severe injury groups. The 20% ACM was added 24 h before hypoxia/reoxygenation or mechanical injury. The morphology and survival of neurons were observed and counted by trypan blue staining. The concentration of NO, lactic dehydrogenase (LDH and membrane ATPase activity were detected by corresponding kits. Results: It was showed that 20% ACM can obviously promote the survival rate of hypoxia/reoxygenated neurons and scratched neurons as well. The morphology and num-ber of neurons exposed to hypoxia or scratch injury showed great difference between groups with or without ACM treatment. Compared with control group, the concentration of NO and LDH was much lower in hypoxic/reoxygenated neurons treated with 20% ACM, and the ATPase activity was higher. For the mechanical injury model, neurons with moderate injury also revealed a lower NO and LDH concen-tration than the control group. All the differences were sta-tistically significant (P<0.05. Conclusion: ACM can promote the survival and func-tional recovery of neurons following hypoxia or scratching to a certain degree. The mechanism may be associated with reducing the synthesis and release of NO and LDH as well as increasing the activity of membrane ATPase. Key words: Glial cell line

  13. Beclin-1-mediated autophagy protects spinal cord neurons against mechanical injury-induced apoptosis.

    Science.gov (United States)

    Wang, Zhen-Yu; Lin, Jian-Hua; Muharram, Akram; Liu, Wen-Ge

    2014-06-01

    Apoptosis has been widely reported to be involved in the pathogenesis associated with spinal cord injury (SCI). Recently, autophagy has also been implicated in various neuronal damage models. However, the role of autophagy in SCI is still controversial and its interrelationship with apoptosis remains unclear. Here, we used an in vitro SCI model to observe a time-dependent induction of autophagy and apoptosis. Mechanical injury induced autophagy markers such as LC3 lipidation, LC3II/LC3I conversion, and Beclin-1 expression. Injured neurons showed decreased cell viability and increased apoptosis. To elucidate the effect of autophagy on apoptosis, the mechanically-injured neurons were treated with the mTOR inhibitor rapamycin and 3-methyl adenine (3-MA), which are known to regulate autophagy positively and negatively, respectively. Rapamycin-treated neurons showed the highest level of cell viability and lowest level of apoptosis among the injured neurons and those treated with 3-MA showed the reciprocal effect. Notably, rapamycin-treated neurons exhibited slightly reduced Bax expression and significantly increased Bcl-2 expression. Furthermore, by plasmid transfection, we showed that Beclin-1-overexpressing neuronal cells responded to mechanical injury with greater LC3II/LC3I conversion and cell viability, lower levels of apoptosis, higher Bcl-2 expression, and unaltered Bax expression as compared to vector control cells. Beclin-1-knockdown neurons showed almost the opposite effects. Taken together, our results suggest that autophagy may serve as a protection against apoptosis in mechanically-injured spinal cord neurons. Targeting mTOR and/or enhancing Beclin-1 expression might be alternative therapeutic strategies for SCI.

  14. Concentration-Dependent Dual Role of Thrombin In Protection of Cultured Rat Cortical Neurons

    Science.gov (United States)

    García, Paul S.; Ciavatta, Vincent T.; Fidler, Jonathan A.; Woodbury, Anna; Levy, Jerrold H.; Tyor, William R.

    2015-01-01

    Background Thrombin’s role in the nervous system is not well understood. Under conditions of blood-brain barrier compromise (e.g., neurosurgery or stroke), thrombin can result in neuroapoptosis and the formation of glial scars. Despite this, preconditioning with thrombin has been found to be neuroprotective in models of cerebral ischemia and intracerebral hemorrhage. Methods We investigated the effects of physiologically relevant concentrations of thrombin on cortical neurons using two culture-based assays. We examined thrombin’s effect on neurites by quantitative analysis of fluorescently labeled neurons. To characterize thrombin’s effects on neuron survival, we spectrophotometrically measured changes in enzymatic activity. Using receptor agonists and thrombin inhibitors, we separately examined the role of thrombin and its receptor in neuroprotection. Results We found that low concentrations of thrombin (1 nM) enhances neurite growth and branching, neuron viability, and protects against excitotoxic damage. In contrast, higher concentrations of thrombin (100 nM) are potentially detrimental to neuronal health as evidenced by inhibition of neurite growth. Lower concentrations of thrombin resulted in equivalent neuroprotection as the antifibrinolytic, aprotinin, and the direct thrombin inhibitor, argatroban. Interestingly, exogenous application of the species-specific thrombin inhibitor, antithrombin III, was detrimental to neuronal health; suggesting that some endogenous thrombin is necessary for optimal neuron health in our culture system. Activation of the thrombin receptor, protease-activated receptor - 1 (PAR-1), via micromolar concentrations of the thrombin receptor agonist peptide, TRAP, did not adversely affect neuronal viability. Conclusions An optimal concentration of thrombin exists to enhance neuronal health. Neurotoxic effects of thrombin do not involve activation of PAR receptors and thus separate pharmacologic manipulation of thrombin’s receptor

  15. Prostaglandin receptor EP2 protects dopaminergic neurons against 6-OHDA-mediated low oxidative stress.

    Science.gov (United States)

    Carrasco, Emilce; Werner, Peter; Casper, Diana

    2008-08-15

    Dopaminergic neurons in the substantia nigra (SN) selectively die in Parkinson's disease (PD), but it is unclear how and why this occurs. Recent findings implicate prostaglandin E(2) (PGE(2)) and two of its four receptors, namely EP1 and EP2, as mediators of degenerative and protective events in situations of acute and chronic neuronal death. EP1 activation can exacerbate excitotoxic damage in stroke models and our recent study showed that EP1 activation may explain the selective sensitivity of dopaminergic neurons to oxidative stress. Conversely, EP2 activation may be neuroprotective, although toxic effects have also been demonstrated. Here we investigated if and how EP2 activation might alter the survival of dopaminergic neurons following selective low-level oxidative injury evoked by the neurotoxin 6-hydroxydopamine (6-OHDA) in primary neuronal cultures prepared from embryonic rat midbrain. We found that cultured dopaminergic neurons displayed EP2 receptors. Butaprost, a selective EP2 agonist, significantly reduced 6-OHDA neurotoxicity. EP2 receptors are coupled to stimulatory G-proteins (Gs), which activate adenylate cyclase, increasing cAMP synthesis, which then activates protein kinase A (PKA). Both dibutyryl cAMP and forskolin reduced dopaminergic cell loss after 6-OHDA exposure. Conversely, KT5720 and H-89, two structurally distinct high-affinity PKA inhibitors, abolished the protective effect of butaprost, implicating cAMP-dependent PKA activity in the neuroprotection by EP2 activation. Finally, we show that melanized dopaminergic neurons in the human SN express EP2. This pathway warrants consideration as a neuroprotective strategy for PD.

  16. Astrocytes require insulin-like growth factor I to protect neurons against oxidative injury.

    Science.gov (United States)

    Genis, Laura; Dávila, David; Fernandez, Silvia; Pozo-Rodrigálvarez, Andrea; Martínez-Murillo, Ricardo; Torres-Aleman, Ignacio

    2014-01-01

    Oxidative stress is a proposed mechanism in brain aging, making the study of its regulatory processes an important aspect of current neurobiological research. In this regard, the role of the aging regulator insulin-like growth factor I (IGF-I) in brain responses to oxidative stress remains elusive as both beneficial and detrimental actions have been ascribed to this growth factor. Because astrocytes protect neurons against oxidative injury, we explored whether IGF-I participates in astrocyte neuroprotection and found that blockade of the IGF-I receptor in astrocytes abrogated their rescuing effect on neurons. We found that IGF-I directly protects astrocytes against oxidative stress (H 2O 2). Indeed, in astrocytes but not in neurons, IGF-I decreases the pro-oxidant protein thioredoxin-interacting protein 1 and normalizes the levels of reactive oxygen species. Furthermore, IGF-I cooperates with trophic signals produced by astrocytes in response to H 2O 2 such as stem cell factor (SCF) to protect neurons against oxidative insult. After stroke, a condition associated with brain aging where oxidative injury affects peri-infarcted regions, a simultaneous increase in SCF and IGF-I expression was found in the cortex, suggesting that a similar cooperative response takes place in vivo. Cell-specific modulation by IGF-I of brain responses to oxidative stress may contribute in clarifying the role of IGF-I in brain aging.

  17. Protective effect of astrocyte-conditioned medium on neurons following hypoxia and mechanical injury

    Institute of Scientific and Technical Information of China (English)

    YAN Ji-wen; TAN Tong-yan; HUANG Qi-lin

    2013-01-01

    Objective:To investigate the protective effect of mouse astrocyte-conditioned medium (ACM)on hypoxic and mechanically injured neurons by a cell model in vitro,and to explore the possible mechanism.Methods:The model of hypoxic neuronal injury was caused by 3% O2 in three-gas incubator.Neurons were cultured with ordinary medium or 20% ACM respectively and randomly divided into hypoxic group (hypoxia for 4,8,24 h and marked as H4R0,H8R0,H24R0) and hypoxia reoxygenation group (H4R24,HSR24,H24R24).Mechanical injury model was developed by scratching neurons cultured in 20% ACM or ordinary medium to different degrees.Neurons in both medium were divided into normal control group,mild,moderate and severe injury groups.The 20% ACM was added 24 h before hypoxia/reoxygenation or mechanical injury.The morphology and survival of neurons were observed and counted by trypan blue staining.The concentration of NO,lactic dehydrogenase (LDH) and membrane ATPase activity were detected by corresponding kits.Results:It was showed that 20% ACM can obviously promote the survival rate of hypoxia/reoxygenated neurons and scratched neurons as well The morphology and number of neurons exposed to hypoxia or scratch injury showed great difference between groups with or without ACM treatment.Compared with control group,the concentration of NO and LDH was much lower in hypoxic/reoxygenated neurons treated with 20% ACM,and the ATPase activity was higher.For the mechanical injury model,neurons with moderate injury also revealed a lower NO and LDH concentration than the control group.All the differences were statistically significant (P<0.05).Conclusion:ACM can promote the survival and functional recovery of neurons following hypoxia or scratching to a certain degree.The mechanism may be associated with reducing the synthesis and release of NO and LDH as well as increasing the activity of membrane ATPase.

  18. Nicotine, but not cotinine, partially protects dopaminergic neurons against MPTP-induced degeneration in mice.

    Science.gov (United States)

    Parain, K; Marchand, V; Dumery, B; Hirsch, E

    2001-02-02

    In order to analyze the putative neuroprotective role of nicotine and cotinine in parkinsonian syndromes, these two compounds were administered in male C57Bl6 mice for 4 weeks. On day 8, four injections of 1-methyl-4-phenyl-1,2,3,6,-tetrahydropyridine (MPTP) were administered. MPTP intoxication induced a 50% loss of dopaminergic neurons in the substantia nigra and a 45% reduction in dopaminergic fibers in the striatum. Administration of cotinine did not affect MPTP toxicity in the nigrostriatal system but chronic nicotine treatment showed a slight protection (15%) of nigrostriatal dopaminergic neurons against MPTP.

  19. Green tea polyphenols protect spinal cord neurons against hydrogen peroxide-induced oxidative stress

    Institute of Scientific and Technical Information of China (English)

    Jianbo Zhao; Shiqiang Fang; Yajiang Yuan; Zhanpeng Guo; Jinhao Zeng; Yue Guo; Peifu Tang; Xifan Mei

    2014-01-01

    Green tea polyphenols are strong antioxidants and can reduce free radical damage. To investigate their neuroprotective potential, we induced oxidative damage in spinal cord neurons using hy-drogen peroxide, and applied different concentrations (50-200 µg/mL) of green tea polyphenol to the cell medium for 24 hours. Measurements of superoxide dismutase activity, malondial-dehyde content, and expression of apoptosis-related genes and proteins revealed that green tea polyphenol effectively alleviated oxidative stress. Our results indicate that green tea polyphenols play a protective role in spinal cord neurons under oxidative stress.

  20. Engrailed protects mouse midbrain dopaminergic neurons against mitochondrial complex I insults

    OpenAIRE

    Alvarez-Fischer, Daniel; Fuchs, Julia; Castagner, François; Stettler, Olivier; Massiani-Beaudoin, Olivia; Moya, Kenneth L.; Bouillot, Colette; Oertel, Wolfgang H; Lombès, Anne; Faigle, Wolfgang; Joshi, Rajiv L.; HARTMANN, Andreas; Prochiantz, Alain

    2011-01-01

    Abstract Mice heterozygous for homeobox gene Engrailed-1 display progressive loss of mesencephalic dopaminergic (mDA) neurons. We report that exogenous Engrailed-1 and Engrailed-2 (collectively Engrailed) protect mDA neurons from 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), a mitochondrial complex I toxin used to model PD in animals. Engrailed enhances the translation of nuclear-encoded mRNAs for two key complex I subunits, Ndufs1 and Ndufs3, and increases complex I activit...

  1. Neuron-derived IgG protects dopaminergic neurons from insult by 6-OHDA and activates microglia through the FcγR I and TLR4 pathways.

    Science.gov (United States)

    Zhang, Jie; Niu, Na; Wang, Mingyu; McNutt, Michael A; Zhang, Donghong; Zhang, Baogang; Lu, Shijun; Liu, Yuqing; Liu, Zhihui

    2013-08-01

    Oxidative and immune attacks from the environment or microglia have been implicated in the loss of dopaminergic neurons of Parkinson's disease. The role of IgG which is an important immunologic molecule in the process of Parkinson's disease has been unclear. Evidence suggests that IgG can be produced by neurons in addition to its traditionally recognized source B lymphocytes, but its function in neurons is poorly understood. In this study, extensive expression of neuron-derived IgG was demonstrated in dopaminergic neurons of human and rat mesencephalon. With an in vitro Parkinson's disease model, we found that neuron-derived IgG can improve the survival and reduce apoptosis of dopaminergic neurons induced by 6-hydroxydopamine toxicity, and also depress the release of NO from microglia triggered by 6-hydroxydopamine. Expression of TNF-α and IL-10 in microglia was elevated to protective levels by neuron-derived IgG at a physiologic level via the FcγR I and TLR4 pathways and microglial activation could be attenuated by IgG blocking. All these data suggested that neuron-derived IgG may exert a self-protective function by activating microglia properly, and IgG may be involved in maintaining immunity homeostasis in the central nervous system and serve as an active factor under pathological conditions such as Parkinson's disease.

  2. Role of carotid body for neuronal protection in experimental subarachnoid haemorrhage

    Directory of Open Access Journals (Sweden)

    Mehmet Dumlu Aydın

    2013-01-01

    Full Text Available Objective: Carotid bodies are known as main arterialchemoregulatory units. Despite well known that carotidbodies have an important role in cerebral circulation andblood pH regulation, their roles has not been investigatedin subarachnoid haemorrhage. We investigated whetherthere is neuroprotective effect of neuron density of carotidbodies on the brain in subarachnoid haemorrhage.Methods: Twenty hybrid rabbits were studied. Four ofthem were used as reference group (n=4 and the remainingwas obliged to subarachnoid haemorrhage by injectingautologous blood into their cisterna magna (n=16and sacrificed after one month. All carotid bodies andbrains examined histopathologically using by stereologicmethods. The relationship between the neuronal densityof carotid body and degenerated neuron density of thehippocampus were compared statistically.Results: Five rabbits with subarachnoid haemorrhagedead during the follow-up time (n=5. The average neuronaldensity of carotid body was 4500±500 cells/mm3and of hippocampus 170.000±17.000 cell/mm3 in normalrabbit family. The degenerated neuron density ofthe hippocampus was 20.000±3.000 cells/mm3 in rabbitswith have high neuron density of carotid body and was65.000±8.000 cells/mm3 in rabbits with low neuron densityof carotid body. The differences between the neuronaldensity of carotid body and the degenerated neuron numbersof the hippocampus were significant.Conclusion: The neuron density of carotid body mayplay an important role on the protection of brain in subarachnoidhaemorrhage.Key words: Subarachnoid haemorrhage, carotid body,hippocampus, neurodegeneration, cerebral ischemia

  3. Protective Effect of Edaravone in Primary Cerebellar Granule Neurons against Iodoacetic Acid-Induced Cell Injury

    Directory of Open Access Journals (Sweden)

    Xinhua Zhou

    2015-01-01

    Full Text Available Edaravone (EDA is clinically used for treatment of acute ischemic stroke in Japan and China due to its potent free radical-scavenging effect. However, it has yet to be determined whether EDA can attenuate iodoacetic acid- (IAA- induced neuronal death in vitro. In the present study, we investigated the effect of EDA on damage of IAA-induced primary cerebellar granule neurons (CGNs and its possible underlying mechanisms. We found that EDA attenuated IAA-induced cell injury in CGNs. Moreover, EDA significantly reduced intracellular reactive oxidative stress production, loss of mitochondrial membrane potential, and caspase 3 activity induced by IAA. Taken together, EDA protected CGNs against IAA-induced neuronal damage, which may be attributed to its antiapoptotic and antioxidative activities.

  4. Protective Effect of Edaravone in Primary Cerebellar Granule Neurons against Iodoacetic Acid-Induced Cell Injury

    Science.gov (United States)

    Zhou, Xinhua; Zhu, Longjun; Wang, Liang; Guo, Baojian; Zhang, Gaoxiao; Sun, Yewei; Zhang, Zaijun; Lee, Simon Ming-Yuen; Yu, Pei; Wang, Yuqiang

    2015-01-01

    Edaravone (EDA) is clinically used for treatment of acute ischemic stroke in Japan and China due to its potent free radical-scavenging effect. However, it has yet to be determined whether EDA can attenuate iodoacetic acid- (IAA-) induced neuronal death in vitro. In the present study, we investigated the effect of EDA on damage of IAA-induced primary cerebellar granule neurons (CGNs) and its possible underlying mechanisms. We found that EDA attenuated IAA-induced cell injury in CGNs. Moreover, EDA significantly reduced intracellular reactive oxidative stress production, loss of mitochondrial membrane potential, and caspase 3 activity induced by IAA. Taken together, EDA protected CGNs against IAA-induced neuronal damage, which may be attributed to its antiapoptotic and antioxidative activities. PMID:26557222

  5. Amentoflavone protects hippocampal neurons: anti-inflammatory, antioxidative, and antiapoptotic effects

    Directory of Open Access Journals (Sweden)

    Zhen Zhang

    2015-01-01

    Full Text Available Amentoflavone is a natural biflavone compound with many biological properties, including anti-inflammatory, antioxidative, and neuroprotective effects. We presumed that amentoflavone exerts a neuroprotective effect in epilepsy models. Prior to model establishment, mice were intragastrically administered 25 mg/kg amentoflavone for 3 consecutive days. Amentoflavone effectively prevented pilocarpine-induced epilepsy in a mouse kindling model, suppressed nuclear factor-κB activation and expression, inhibited excessive discharge of hippocampal neurons resulting in a reduction in epileptic seizures, shortened attack time, and diminished loss and apoptosis of hippocampal neurons. Results suggested that amentoflavone protected hippocampal neurons in epilepsy mice via anti-inflammation, antioxidation, and antiapoptosis, and then effectively prevented the occurrence of seizures.

  6. Gentianine protects hippocampal neurons in a rat model of recurrent febrile convulsion

    Institute of Scientific and Technical Information of China (English)

    Xuewei Liu; Shumin Liu; Na Wang; Fang Lu; Min Cao

    2011-01-01

    Gentianine has been shown to have a protective effect on hippocampal CA1 neurons in rats subjected to recurrent febrile convulsion (FC).The present study sought to explore the possible mechanism of gentianine by intraperitoneally injecting gentianine into rats with warm water-induced FC.The results revealed that neuronal organelle injury was slightly ameliorated in the hippocampal CA1 region.The level of glutamate was decreased,but the level of γ-aminobutyric acid was increased,as detected by ninhydrin staining.In addition,glutamate acid decarboxylase expression in hippocampal CA1 was increased,as determined by immunohistochemistry.The results demonstrated that gentianine can ameliorate FC-induced neuronal injury by enhancing glutamate acid decarboxylase activity,decreasing glutamate levels and increasing γ-aminobutyric acid levels.

  7. Ibuprofen protects ischemia-induced neuronal injury via up-regulating interleukin-1 receptor antagonist expression.

    Science.gov (United States)

    Park, E-M; Cho, B-P; Volpe, B T; Cruz, M O; Joh, T H; Cho, S

    2005-01-01

    The inflammatory response accompanies and exacerbates the developing injury after cerebral ischemia. Ibuprofen, a non-steroidal anti-inflammatory drug, has been shown to attenuate injuries in animal models of various neurological diseases. In the present study, we investigated ibuprofen's neuroprotective effects in rats exposed to transient forebrain ischemia and in cultures exposed to oxygen glucose deprivation (OGD). Rats treated with ibuprofen after transient forebrain ischemia displayed long-lasting protection of CA1 hippocampal neurons. There were selective increases in interleukin-1 receptor antagonist gene and protein expression in ibuprofen-treated OGD microglia. Furthermore, treatment with ibuprofen in neuron/microglia co-cultures increased the number of surviving HC2S2 neurons against OGD whereas IL-1ra neutralizing antibody reversed the ibuprofen-induced neuroprotection. The data indicate that ibuprofen-induced IL-1ra secretion is involved in neuroprotection against ischemic conditions.

  8. Protective effects of icariin on neurons injured by cerebral ischemia/reperfusion

    Institute of Scientific and Technical Information of China (English)

    LI Li; ZHOU Qi-xin; SHI Jing-shan

    2005-01-01

    Background It is very important to search for novel anti-ischemia/reperfusion neuroprotective drugs for prevention or treatment of cerebrovascular diseases. Icariin, the major active component of traditional Chinese herb Yinyanghuo, may have a beneficial role for neurons in cerebral ischemia/reperfusion caused by accident. However, it was not clear yet. In this study, we observed the protective effects of icariin on neurons injured by ischemia/reperfusion in vitro and in vivo and investigated its protective mechanism.Methods Cerebral cortical neurons of Wistar rats in primary culture were studied during the different periods of oxygen-glucose deprivation and reperfusion with oxygen and glucose. Cell viability was determined by methyl thiazoleterazolium (MTT) assay. The activity of lactate dehydrogenase (LDH) leaked from neurons, cell apoptosis and the concentration of intracellular free calcium were measured respectively. On the other hand, the mice model of transient cerebral ischemia/reperfusion was made by bilateral occlusion of common carotid arteries and ischemic hypotension/reperfusion. The mice were divided into several groups at random: sham operated group, model group and icariin preventive treatment group. The changes of mice behavioral, activities of superoxide dismutase (SOD) and the content of malondialdehyde (MDA) were measured, respectively. Results Treatment with icariin (final concentration 0.25, 0.5, and 1 mg/L) during ischemia/reperfusion-mimetic incubation in vitro concentration-dependently attenuated neuronal damage with characteristics of increasing injured neuronal absorbance of MTT, decreasing LDH release, decreasing cell apoptosis, and blunting elevation of intracellular calcium concentration. And in vivo the learning and memory abilities significantly decreased,activities of SOD were diminished and MDA level increased obviously in model group,compared with that in sham operated group. But pre-treatment of model mice with icariin (10, 30

  9. Protective effect of melatonin on neurons after oxidative-stress injury

    Institute of Scientific and Technical Information of China (English)

    Ximing Wang; Zhiqiang Lu; Qiuhong Duan; Tao Lu; Shanshu He

    2006-01-01

    BACKGROUND: It has been suggested that melatonin(MT) can protect secondary neuronal injury.However,the protective effect of MT on neuronal injury in ischemia/reperfusion models in vitro still has not been proved.OBJECTIVE:To investigate the protective effect of MT on central ischemic injury of nerve cells and analyze its possible mechanism.DESIGN: Contrast observational study.SETTING: Department of Biochemistry and Molecular Biology,Tongji Medical College,Huazhong University of Science and Technology.MATERIALS: Rats aged 7-8 days and weighing 10-12g were provided by Medical Experimental Animal Center,Tongji Medical College,Huazhong University of Science and Technology,MT was provided by Sigma Company,USA.METHODS:The experiment was carried out in the Laboratory of Biochemistry and Molecular Biology,Tongji Hospital,Huazhong University of Science and Technology from October 2002 to March 2004.The effects of MT on the neurodegeneration induced by oxygen-glucose-deprivation (OGD) were tested in cultured rat cerebellar granule cells.Neuron damage was quantitatively assessed by Typan Blue exclusion and MTT assay at different time points after oxygen-glucose-deprivation(90 minutes).DNA gel electrophoresis and acridine orange stain were performed to determine the nature of cell damage.And fluorescence spectrophotometer was used for quantification of intracellular malondialdehyde(MDA)at various time intervals.MAIN OUTCOME MEASURES: Correlation between degrees of neuronal injury and reperfusion times,apoptosis,and production of MDA in cells.RESULTS:①The neuron injury was aggravated with reperfusion time.②The protective effect of MT was time-and dose-dependent when its concentration was not higher than 10 μmol/L.⑧When neurons were exposed to OGD for 90 minutes.part of the cells exhibited typical features of apoptosis:internucleosomal DNA condensation and DNA ladder on agarose gel electrophoresis.MT added to cells recovering from OGD exerted neuroprotective action

  10. pSVPoMcat modifying Schwann cell to protect injured spinal neurons in rats

    Institute of Scientific and Technical Information of China (English)

    陈礼刚; 高立达; 朴永旭; 毛伯镛; 曾凡俊

    2002-01-01

    Objective: To investigate the protective effect of pSVPoMcat (myelin basic protein microgene)modifying Schwann cell on injured spinal neurons.Methods: A model of rat spinal cord injured by hemisection was used. One hundred and twenty healthy SD rats of both sexes weighing 250-300 g were divided into three groups: Group A (n=40, treated with implantation of pSVPoMcat modifying Schwann cell), Group B (n= 40, treated with implantation of Schwann cell only) and Group C (n=400, treated with sham operation as the control). One week after operation the rat functional recovery was observed dynamically by using combined behavioral score (CBS) and cortical somatasensory evoked potentials, the spinal cord sections were stained by Nissl, acid phosphatase enzyme histochemistry and cell apoptosis was examined by methye green, terminal deoxynucleotidyl and the dUTP Nick end labeling technique. Quantitative analysis was done by computer image analysis system.Results: In Group A the injured neurons recovered well morphologically. The imaging analysis showed a result of Group A>Group B>Group C in the size of the neurons (P<0.01). The percentage of ACP (acid phosphatase) stained area and the rate of apoptosis sequence were groups Aprotective effect on injured spinal neurons and promotes recovery of injured spinal cord function in rats.

  11. Bifunctional apoptosis inhibitor (BAR) protects neurons from diverse cell death pathways.

    Science.gov (United States)

    Roth, W; Kermer, P; Krajewska, M; Welsh, K; Davis, S; Krajewski, S; Reed, J C

    2003-10-01

    The bifunctional apoptosis regulator (BAR) is a multidomain protein that was originally identified as an inhibitor of Bax-induced apoptosis. Immunoblot analysis of normal human tissues demonstrated high BAR expression in the brain, compared to low or absent expression in other organs. Immunohistochemical staining of human adult tissues revealed that the BAR protein is predominantly expressed by neurons in the central nervous system. Immunofluorescence microscopy indicated that BAR localizes mainly to the endoplasmic reticulum (ER) of cells. Overexpression of BAR in CSM 14.1 neuronal cells resulted in significant protection from a broad range of cell death stimuli, including agents that activate apoptotic pathways involving mitochondria, TNF-family death receptors, and ER stress. Downregulation of BAR by antisense oligonucleotides sensitized neuronal cells to induction of apoptosis. Moreover, the search for novel interaction partners of BAR identified several candidate proteins that might contribute to the regulation of neuronal apoptosis (HIP1, Hippi, and Bap31). Taken together, the expression pattern and functional data suggest that the BAR protein is involved in the regulation of neuronal survival.

  12. Acute bioenergetic intervention or pharmacological preconditioning protects neuron against ischemic injury

    OpenAIRE

    2013-01-01

    Although acute ischemic stroke has high mortality and morbidity rate but yet still has very limited treatment. In this study we have tested the concept of neuron protection by acute bioenergetic intervention or by pharmacological preconditioning with natural antioxidants. Adenosine triphosphate (ATP), pentobarbital, and suramin were encapsulated in pH-sensitive liposomes and used as bioenergy stabilizer. We induced ATP depletion model by incubating cells with media added with ATP-depleting ag...

  13. γ-Tocotrienol does not substantially protect DS neurons from hydrogen peroxide-induced oxidative injury

    Directory of Open Access Journals (Sweden)

    Then Sue-Mian

    2012-01-01

    Full Text Available Abstract Background Down syndrome (DS neurons are more susceptible to oxidative stress and previous studies have shown that vitamin E was able to reduce oxidative stress and improve DS neurons' viability. Therefore, this study was done to investigate the protective role of γ-tocotrienol (γT3 in DS neurons from hydrogen peroxide (H2O2 -induced oxidative stress. The pro-apoptosis tendency of γT3 was compared to α-tocopherol (αT in non-stress condition as well. Methods Primary culture of DS and euploid neurons were divided into six groups of treatment: control, H2O2, γT3 pre-treatment with H2O2, γT3 only, αT pre-treatment with H2O2 and αT only. The treatments were assessed by MTS assay and apoptosis assay by single-stranded DNA (ssDNA apoptosis ELISA assay, Hoechst and Neu-N immunofluorescence staining. The cellular uptake of γT3 and αT was determined by HPLC while protein expressions were determined by Western blot. Comparison between groups was made by the Student's t test, one-way ANOVA and Bonferroni adjustment as well as two-way ANOVA for multiple comparisons. Results One day incubation of γT3 was able to reduced apoptosis of DS neurons by 10%, however γT3 was cytotoxic at longer incubation period (14 days and at concentrations ≥ 100 μM. Pre-treatment of αT and γT3 only attenuate apoptosis and increase cell viability in H2O2-treated DS and euploid neurons by 10% in which the effects were minimal to maintain most of the DS cells' morphology. γT3 act as a free radical scavenger by reducing ROS generated by H2O2. In untreated controls, DS neurons showed lower Bcl-2/Bax ratio and p53 expression compared to normal neurons, while cPKC and PKC-δ expressions were higher in DS neurons. On the other hand, pre-treatment of γT3 in H2O2-treated DS neurons have reduced Bcl-2/Bax ratio, which was not shown in euploid neurons. This suggests that pre-treatment of γT3 did not promote DS cell survival. Meanwhile γT3 and αT treatments

  14. Acetyl L-carnitine protects motor neurons and Rohon-Beard sensory neurons against ketamine-induced neurotoxicity in zebrafish embryos.

    Science.gov (United States)

    Cuevas, Elvis; Trickler, William J; Guo, Xiaoqing; Ali, Syed F; Paule, Merle G; Kanungo, Jyotshna

    2013-01-01

    Ketamine, a non-competitive antagonist of N-methyl-D-aspartate (NMDA) type glutamate receptors is commonly used as a pediatric anesthetic. Multiple studies have shown ketamine to be neurotoxic, particularly when administered during the brain growth spurt. Previously, we have shown that ketamine is detrimental to motor neuron development in the zebrafish embryos. Here, using both wild type (WT) and transgenic (hb9:GFP) zebrafish embryos, we demonstrate that ketamine is neurotoxic to both motor and sensory neurons. Drug absorption studies showed that in the WT embryos, ketamine accumulation was approximately 0.4% of the original dose added to the exposure medium. The transgenic embryos express green fluorescent protein (GFP) localized in the motor neurons making them ideal for evaluating motor neuron development and toxicities in vivo. The hb9:GFP zebrafish embryos (28 h post fertilization) treated with 2 mM ketamine for 20 h demonstrated significant reductions in spinal motor neuron numbers, while co-treatment with acetyl L-carnitine proved to be neuroprotective. In whole mount immunohistochemical studies using WT embryos, a similar effect was observed for the primary sensory neurons. In the ketamine-treated WT embryos, the number of primary sensory Rohon-Beard (RB) neurons was significantly reduced compared to that in controls. However, acetyl L-carnitine co-treatment prevented ketamine-induced adverse effects on the RB neurons. These results suggest that acetyl L-carnitine protects both motor and sensory neurons from ketamine-induced neurotoxicity.

  15. A major role for Tau in neuronal DNA and RNA protection in vivo under physiological and hyperthermic conditions

    Directory of Open Access Journals (Sweden)

    Marie eViolet

    2014-03-01

    Full Text Available Nucleic acid protection is a substantial challenge for neurons, which are continuously exposed to oxidative stress in the brain. Neurons require powerful mechanisms to protect DNA and RNA integrity and ensure their functionality and longevity. Beside its well known role in microtubule dynamics, we recently discovered that Tau is also a key nuclear player in the protection of neuronal genomic DNA integrity under reactive oxygen species (ROS-inducing heat stress (HS conditions in primary neuronal cultures. In this report, we analyzed the capacity of Tau to protect neuronal DNA integrity in vivo in adult mice under physiological and HS conditions. We designed an in vivo mouse model of hyperthermia/HS to induce a transient increase in ROS production in the brain. Comet and TUNEL assays demonstrated that Tau protected genomic DNA in adult cortical and hippocampal neurons in vivo under physiological conditions in wild-type and Tau-deficient (KO-Tau mice. HS increased DNA breaks in KO-Tau neurons. Notably, KO-Tau hippocampal neurons in the CA1 subfield restored DNA integrity after HS more weakly than the dentate gyrus neurons. The formation of phosphorylated histone H2AX foci, a double-strand break marker, was observed in KO-Tau neurons only after HS, indicating that Tau deletion did not trigger similar DNA damage under physiological or HS conditions. Moreover, genomic DNA and cytoplasmic and nuclear RNA integrity were altered under HS in hippocampal neurons exhibiting Tau deficiency, which suggests that Tau also modulates RNA metabolism. Our results suggest that Tau alterations lead to a loss of its nucleic acid safeguarding functions and participate in the accumulation of DNA and RNA oxidative damage observed in the Alzheimer’s disease brain.

  16. Protective effect of melatonin on myenteric neuron damage in experimental colitis in rats.

    Science.gov (United States)

    Shang, Boxin; Shi, Haitao; Wang, Xiaoyan; Guo, Xiaoyan; Wang, Nan; Wang, Yan; Dong, Lei

    2016-04-01

    Inflammation of the colon in patients with ulcerative colitis (UC) causes pain and altered motility, at least in part through the damage of the myenteric neurons (MNs). Thus, it is important to evaluate new drugs for UC treatment that could also protect myenteric neurons efficiently. As a well-known neural protective and anti-inflammatory agent, melatonin could protect neurons from damage through the activation of the nuclear factor erythroid 2-related factor 2 and antioxidant responsive element (Nrf2-ARE) signaling pathway. Therefore, we investigated the potential protective effect of melatonin against MN damage during colitis induced by 2,4-dinitrobenzene sulfonic acid (DNBS) in rats. Colitis was induced by intracolonic (i.c.) instillation of DNBS and treated with melatonin at a dose of 2.5 mg/kg for 4 days. The damage of MN in the left colon was immunohistochemically evaluated in different groups. Ulcerations and inflammation in the colon were semiquantitatively observed. Myeloperoxidase (MPO), superoxide dismutase (SOD), and malondialdehyde (MDA) levels were detected to evaluate the inflammatory and oxidative stress status. The protein and mRNA expressions of Nrf2 and heme oxygenase-1 (HO-1) in the colon were detected by Western blot and quantitative polymerase chain reaction (qPCR), respectively. Melatonin partially prevented the loss of MN and alleviated the inflammation and oxidative stress induced by DNBS. In addition, melatonin markedly increased the Nrf2 and HO-1 level in the colitis. These results indicate that melatonin protects MN from damage by reducing inflammation and oxidative stress, effects that are partly mediated by the Nrf2-ARE pathway.

  17. Cortical excitatory neurons become protected from cell division during neurogenesis in an Rb family-dependent manner.

    Science.gov (United States)

    Oshikawa, Mio; Okada, Kei; Nakajima, Kazunori; Ajioka, Itsuki

    2013-06-01

    Cell cycle dysregulation leads to abnormal proliferation and cell death in a context-specific manner. Cell cycle progression driven via the Rb pathway forces neurons to undergo S-phase, resulting in cell death associated with the progression of neuronal degeneration. Nevertheless, some Rb- and Rb family (Rb, p107 and p130)-deficient differentiating neurons can proliferate and form tumors. Here, we found in mouse that differentiating cerebral cortical excitatory neurons underwent S-phase progression but not cell division after acute Rb family inactivation in differentiating neurons. However, the differentiating neurons underwent cell division and proliferated when Rb family members were inactivated in cortical progenitors. Differentiating neurons generated from Rb(-/-); p107(-/-); p130(-/-) (Rb-TKO) progenitors, but not acutely inactivated Rb-TKO differentiating neurons, activated the DNA double-strand break (DSB) repair pathway without increasing trimethylation at lysine 20 of histone H4 (H4K20), which has a role in protection against DNA damage. The activation of the DSB repair pathway was essential for the cell division of Rb-TKO differentiating neurons. These results suggest that newly born cortical neurons from progenitors become epigenetically protected from DNA damage and cell division in an Rb family-dependent manner.

  18. FDA-approved drugs that protect mammalian neurons from glucose toxicity slow aging dependent on cbp and protect against proteotoxicity.

    Directory of Open Access Journals (Sweden)

    Alex Lublin

    Full Text Available Screening a library of drugs with known safety profiles in humans yielded 30 drugs that reliably protected mammalian neurons against glucose toxicity. Subsequent screening demonstrated that 6 of these 30 drugs increase lifespan in C. elegans: caffeine, ciclopirox olamine, tannic acid, acetaminophen, bacitracin, and baicalein. Every drug significantly reduced the age-dependent acceleration of mortality rate. These protective effects were blocked by RNAi inhibition of cbp-1 in adults only, which also blocks protective effects of dietary restriction. Only 2 drugs, caffeine and tannic acid, exhibited a similar dependency on DAF-16. Caffeine, tannic acid, and bacitracin also reduced pathology in a transgenic model of proteotoxicity associated with Alzheimer's disease. These results further support a key role for glucose toxicity in driving age-related pathologies and for CBP-1 in protection against age-related pathologies. These results also provide novel lead compounds with known safety profiles in human for treatment of age-related diseases, including Alzheimer's disease and diabetic complications.

  19. Septo-hippocampal deafferentation protects CA1 neurons against ischemic injury.

    Science.gov (United States)

    Buchan, A M; Pulsinelli, W A

    1990-03-26

    Excessive synaptic excitation caused by transient cerebral ischemia has been proposed to explain the greater vulnerability of specific neuronal populations to ischemic injury. We tested this hypothesis in rats by cutting, alone or in combination, the afferent fibers that travel in the fimbria/fornix, the perforant, or the Schäffer collateral pathways and innervate the right CA1 hippocampus. Seven to twelve days later the animals were subjected to 30 min of reversible forebrain ischemia. Irreversible damage to the CA1 neurons was assessed with the light microscope after 70-120 h of cerebral reperfusion. The left, unlesioned hippocampus served as a control. Simultaneous cutting of the 3 major afferent pathways significantly reduced CA1 neuronal damage compared to the unlesioned side (P less than 0.001) or to sham-lesioned controls (P less than 0.001). Selective lesions of the fimbria/fornix but not the perforant or the Schäffer collateral pathways also protected against ischemic CA1 damage. These data indicate that afferent fiber input modulates hippocampal damage caused by ischemia, but they are inconsistent with the hypothesis that excitatory afferent fibers, travelling in either the perforant or the Schäffer collateral pathways alone, play a major role. Neurotransmitters, other than those activating excitatory amino acid receptors or yet-to-be-identified synaptic events, may be invoked to explain the spatial and temporal sensitivity of hippocampal CA1 neurons to ischemia.

  20. Molecular Mechanisms Responsible for Neuron-Derived Conditioned Medium (NCM)-Mediated Protection of Ischemic Brain.

    Science.gov (United States)

    Lin, Chi-Hsin; Wang, Chen-Hsuan; Hsu, Shih-Lan; Liao, Li-Ya; Lin, Ting-An; Hsueh, Chi-Mei

    2016-01-01

    The protective value of neuron-derived conditioned medium (NCM) in cerebral ischemia and the underlying mechanism(s) responsible for NCM-mediated brain protection against cerebral ischemia were investigated in the study. NCM was first collected from the neuronal culture growing under the in vitro ischemic condition (glucose-, oxygen- and serum-deprivation or GOSD) for 2, 4 or 6 h. Through the focal cerebral ischemia (bilateral CCAO/unilateral MCAO) animal model, we discovered that ischemia/reperfusion (I/R)-induced brain infarction was significantly reduced by NCM, given directly into the cistern magna at the end of 90 min of CCAO/MCAO. Immunoblocking and chemical blocking strategies were applied in the in vitro ischemic studies to show that NCM supplement could protect microglia, astrocytes and neurons from GOSD-induced cell death, in a growth factor (TGFβ1, NT-3 and GDNF) and p-ERK dependent manner. Brain injection with TGFβ1, NT3, GDNF and ERK agonist (DADS) alone or in combination, therefore also significantly decreased the infarct volume of ischemic brain. Moreover, NCM could inhibit ROS but stimulate IL-1β release from GOSD-treated microglia and limit the infiltration of IL-β-positive microglia into the core area of ischemic brain, revealing the anti-oxidant and anti-inflammatory activities of NCM. In overall, NCM-mediated brain protection against cerebral ischemia has been demonstrated for the first time in S.D. rats, due to its anti-apoptotic, anti-oxidant and potentially anti-glutamate activities (NCM-induced IL-1β can inhibit the glutamate-mediated neurotoxicity) and restriction upon the infiltration of inflammatory microglia into the core area of ischemic brain. The therapeutic potentials of NCM, TGFβ1, GDNF, NT-3 and DADS in the control of cerebral ischemia in human therefore have been suggested and require further investigation.

  1. The effects of prednisone and steroid-sparing agents on decay accelerating factor (CD55) expression: implications in myasthenia gravis.

    Science.gov (United States)

    Auret, Jennifer; Abrahams, Amaal; Prince, Sharon; Heckmann, Jeannine M

    2014-06-01

    Decay accelerating factor (DAF) expression at the muscle endplate is an important defence against complement-mediated damage in myasthenia gravis. Previously we implicated the c.-198C>G DAF polymorphism with the development of treatment-resistant myasthenia-associated ophthalmoplegia by showing that the C>G DAF polymorphism prevented lipopolysaccharide-induced upregulation of lymphoblast DAF. We postulated that drugs used in myasthenia gravis may increase the susceptibility of extraocular muscles to complement-mediated damage and studied their effects on endogenous DAF using patient-derived lymphoblasts as well as mouse myotubes. We show that prednisone repressed C>G DAF expression in lymphoblasts and increased their susceptibility to cytotoxicity. Methotrexate, but not azathioprine or cyclosporine, increased DAF in C>G lymphoblasts. In mouse myotubes expressing wild-type Daf, prednisone also repressed Daf expression. Although cyclosporine, azathioprine, and methotrexate increased muscle Daf levels when used alone, upon co-treatment with prednisone only azathioprine maintained myotube Daf levels close to basal. Therefore, prednisone negatively influences DAF expression in C>G lymphoblasts and in myotubes expressing wild-type Daf. We speculate that myasthenic individuals at risk of developing the ophthalmoplegic complication, such as those with C>G DAF, may have inadequate endogenous levels of complement regulatory protein protection in their extraocular muscle in response to prednisone, increasing their susceptibility to complement-mediated damage.

  2. Cellular model of neuronal atrophy induced by DYNC1I1 deficiency reveals protective roles of RAS-RAF-MEK signaling

    Directory of Open Access Journals (Sweden)

    Zhi-Dong Liu

    2016-08-01

    Full Text Available Abstract Neuronal atrophy is a common pathological feature occurred in aging and neurodegenerative diseases. A variety of abnormalities including motor protein malfunction and mitochondrial dysfunction contribute to the loss of neuronal architecture; however, less is known about the intracellular signaling pathways that can protect against or delay this pathogenic process. Here, we show that the DYNC1I1 deficiency, a neuron-specific dynein intermediate chain, causes neuronal atrophy in primary hippocampal neurons. With this cellular model, we are able to find that activation of RAS-RAF-MEK signaling protects against neuronal atrophy induced by DYNC1I1 deficiency, which relies on MEK-dependent autophagy in neuron. Moreover, we further reveal that BRAF also protects against neuronal atrophy induced by mitochondrial impairment. These findings demonstrate protective roles of the RAS-RAF-MEK axis against neuronal atrophy, and imply a new therapeutic target for clinical intervention.

  3. pSVPoMcat modifying Schwann cell to protect injured spinal neurons in rats

    Institute of Scientific and Technical Information of China (English)

    陈礼刚; 高立达; 等

    2002-01-01

    Objective:To investigate the protective effect of pSVPoMcat(myelin basic protein microgene)modifying Schwann cell on injured spinal neurons.Methods;A model of rat spinal cord injured by hemisection was used.One hundred and twenty healthy SD rats of both sexes weighing 250-300g were divided into three groups:GroupA(n=40,treated with implantation of pSPVoMcat modifying Schwann cell),GroupB(n=40,treated with implantation of Schwann cell only)and GroupC(n=400,treated with sham operation as the control).One week after operation the rat functional recovery was observed dynamically by using combined behavioral score(CBS)and cortical somatasensory evoked potentials,the spinal cord sections were stained by Nissl,acid phosphatase enzyme histochemistry and cell apoptosis was examined by metye green,terminal deoxynucleotidyl and the dUTP Nick end labeling technique.Quantitative analysis was done by computer image analysis system.Results:In Group A the injured neurons recovered well morphologically.The imaging analysis showed a result of GroupA>GroupB>Group Cin the size of the neurons (P<0.01),The percentage of ACP(acid phosphatase) stained area and the rate of apoptosis sequence were groupsAprotective effect on injured spinal neurons and promotes recovery of injured spinal cord function in rats.

  4. Caffeic acid phenethyl ester protects against the dopaminergic neuronal loss induced by 6-hydroxydopamine in rats.

    Science.gov (United States)

    Barros Silva, R; Santos, N A G; Martins, N M; Ferreira, D A S; Barbosa, F; Oliveira Souza, V C; Kinoshita, A; Baffa, O; Del-Bel, E; Santos, A C

    2013-03-13

    Caffeic acid phenethyl ester (CAPE) is a botanical compound abundant in honeybees' propolis. It has anti-inflammatory, antiviral, antioxidant, immunomodulatory and antitumor properties. Its beneficial effects against neurodegenerative diseases, including Parkinson's disease, have also been suggested and some mechanisms have been proposed. Mitochondrial damage and oxidative stress are critical events in neurodegeneration. Release of cytochrome c from mitochondria to cytosol and the downstream activation of caspase-3 have been suggested as targets of the protective mechanism of CAPE. Most of the studies addressing the protective effect of CAPE have been performed in cell culture. This is the first study to demonstrate the protective effect of CAPE against the dopaminergic neuronal loss induced by 6-hydroxydopamine (6-OHDA) in rats. It also demonstrates, for the first time, the inhibitory effect of CAPE on mitochondrial permeability transition (MPT), a mediator of neuronal death that triggers cytochrome c release and caspase-3 activation. Scavenging of reactive oxygen species (ROS) and metal chelation was demonstrated in the brain-affected areas of the rats treated with 6-OHDA and CAPE. Additionally, we demonstrated that CAPE does not affect brain mitochondrial function. Based on these findings and on its ability to cross the blood-brain barrier, CAPE is a promising compound to treat Parkinson's and other neurodegenerative diseases.

  5. Cerebrospinal lfuid from rats given hypoxic preconditioning protects neurons from oxygen-glucose deprivation-induced injury

    Institute of Scientific and Technical Information of China (English)

    Yan-bo Zhang; Zheng-dong Guo; Mei-yi Li; Si-jie Li; Jing-zhong Niu; Ming-feng Yang; Xun-ming Ji; Guo-wei Lv

    2015-01-01

    Hypoxic preconditioning activates endogenous mechanisms that protect against cerebral isch-emic and hypoxic injury. To better understand these protective mechanisms, adult rats were housed in a hypoxic environment (8% O2/92% N2) for 3 hours, and then in a normal oxygen environment for 12 hours. Their cerebrospinal fluid was obtained to culture cortical neurons from newborn rats for 1 day, and then the neurons were exposed to oxygen-glucose deprivation for 1.5 hours. The cerebrospinal lfuid from rats subjected to hypoxic preconditioning reduced oxygen-glucose deprivation-induced injury, increased survival rate, upregulated Bcl-2 expression and downregulated Bax expression in the cultured cortical neurons, compared with control. These results indicate that cerebrospinal lfuid from rats given hypoxic preconditioning protects against oxygen-glucose deprivation-induced injury by affecting apoptosis-related protein expres-sion in neurons from newborn rats.

  6. Cerebrospinal fluid from rats given hypoxic preconditioning protects neurons from oxygen-glucose deprivation-induced injury.

    Science.gov (United States)

    Zhang, Yan-Bo; Guo, Zheng-Dong; Li, Mei-Yi; Li, Si-Jie; Niu, Jing-Zhong; Yang, Ming-Feng; Ji, Xun-Ming; Lv, Guo-Wei

    2015-09-01

    Hypoxic preconditioning activates endogenous mechanisms that protect against cerebral ischemic and hypoxic injury. To better understand these protective mechanisms, adult rats were housed in a hypoxic environment (8% O2/92% N2) for 3 hours, and then in a normal oxygen environment for 12 hours. Their cerebrospinal fluid was obtained to culture cortical neurons from newborn rats for 1 day, and then the neurons were exposed to oxygen-glucose deprivation for 1.5 hours. The cerebrospinal fluid from rats subjected to hypoxic preconditioning reduced oxygen-glucose deprivation-induced injury, increased survival rate, upregulated Bcl-2 expression and downregulated Bax expression in the cultured cortical neurons, compared with control. These results indicate that cerebrospinal fluid from rats given hypoxic preconditioning protects against oxygen-glucose deprivation-induced injury by affecting apoptosis-related protein expression in neurons from newborn rats.

  7. Tetraspanin (TSP-17 protects dopaminergic neurons against 6-OHDA-induced neurodegeneration in C. elegans.

    Directory of Open Access Journals (Sweden)

    Neda Masoudi

    2014-12-01

    Full Text Available Parkinson's disease (PD, the second most prevalent neurodegenerative disease after Alzheimer's disease, is linked to the gradual loss of dopaminergic neurons in the substantia nigra. Disease loci causing hereditary forms of PD are known, but most cases are attributable to a combination of genetic and environmental risk factors. Increased incidence of PD is associated with rural living and pesticide exposure, and dopaminergic neurodegeneration can be triggered by neurotoxins such as 6-hydroxydopamine (6-OHDA. In C. elegans, this drug is taken up by the presynaptic dopamine reuptake transporter (DAT-1 and causes selective death of the eight dopaminergic neurons of the adult hermaphrodite. Using a forward genetic approach to find genes that protect against 6-OHDA-mediated neurodegeneration, we identified tsp-17, which encodes a member of the tetraspanin family of membrane proteins. We show that TSP-17 is expressed in dopaminergic neurons and provide genetic, pharmacological and biochemical evidence that it inhibits DAT-1, thus leading to increased 6-OHDA uptake in tsp-17 loss-of-function mutants. TSP-17 also protects against toxicity conferred by excessive intracellular dopamine. We provide genetic and biochemical evidence that TSP-17 acts partly via the DOP-2 dopamine receptor to negatively regulate DAT-1. tsp-17 mutants also have subtle behavioral phenotypes, some of which are conferred by aberrant dopamine signaling. Incubating mutant worms in liquid medium leads to swimming-induced paralysis. In the L1 larval stage, this phenotype is linked to lethality and cannot be rescued by a dop-3 null mutant. In contrast, mild paralysis occurring in the L4 larval stage is suppressed by dop-3, suggesting defects in dopaminergic signaling. In summary, we show that TSP-17 protects against neurodegeneration and has a role in modulating behaviors linked to dopamine signaling.

  8. Brain-derived neurotrophic factor protects neurons from GdCl3-induced impairment in neuron-astrocyte co-cultures

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Gadolinium (Gd3+) complexes are important contrast agents in medical magnetic resonance imaging (MRI) and of great potential value in brain research. In order to better understand the mechanisms of the action of Gd3+ on neurons in the complex central nervous system (CNS), the neurotoxic actions of GdCl3 have been investigated in both neuron monoculture and astrocyte-neuron co-culture systems. Measurements of lactate dehydrogenase release showed that GdCl3 causes significant cell death of monocultured neurons as a result of reactive oxygen species (ROS) generation and down-regulation of brain-derived neurotrophic factor (BDNF). However, GdCl3 does not affect the viability and BDNF expression of astrocytes. Both co-culturing of neurons with astrocytes and addition of BDNF ameliorated GdCl3-induced neurotoxicity by decreasing ROS generation and facilitating recovery of BDNF levels. The results obtained suggest that astrocytes in the CNS may protect neurons from GdCl3-induced impairment through secreting BDNF and thus up-regulating BDNF expression and interfering with Gd3+-induced cell signaling in neurons. A possible molecular mechanism is suggested which should be helpful in understand- ing the neurotoxic actions of gadolinium probes .

  9. Aged garlic extract and its components protect cultured rat hippocampal neurons from amyloid β—protein—in—duced neuronal death

    Institute of Scientific and Technical Information of China (English)

    ItoY; KosuY

    2002-01-01

    Aged garlic extract and its components such as S-allyl-L-cysteine (SAC) and sllixin have been shown to possess various biological effects including neurotrophic activity.We characterized the neuronal death induced by amyloid β-protein (Aβ),4-hydroxynoenal (HNE),tunicamycin(TM),and trophic factor-deprivation (TFD),and ivestigated whether these garlic compounds could prevent this in cultured PC12 cells and rat hippocampal neurons.Treatment with SAC protected these cells against Aβ- and TM-induced neuronal death.SAC also attenuated the processing of procaspase-12 induced by Aβ25-35 or TM.In contrast,allixin and its analogue,DHP,afforded no protection against Aβ-induced cell death.SAC afforded no protection against HNE- and TFD-induced cell death,which has been shown to be mediated by caspase-3 dependent pathway.These results suggest that SAC protect against the neuronal cell death that is triggered by ER dysfunction.

  10. Limitations of Mild, Moderate, and Profound Hypothermia in Protecting Developing Hippocampal Neurons After Simulated Ischemia.

    Science.gov (United States)

    Gregersen, Maren; Lee, Deok Hee; Gabatto, Pablo; Bickler, Philip E

    2013-12-01

    Mild hypothermia (33°C-34°C) after cerebral ischemia in intact animals or ischemia-like conditions in vitro reduces neuron death. However, it is now clear that more profound hypothermia or delayed hypothermia may not provide significant protection. To further define the limitations of hypothermia after cerebral ischemia, we used hippocampal slice cultures to examine the effects of various degrees, durations, and delays of hypothermia on neuron death after an ischemia-like insult. Organotypic cultures of the hippocampus from 7- to 8 day-old rat pups were cooled to 32°C, 23°C, 17°C, or 4°C immediately or after a 2-4 hour delay from an injurious insult of oxygen and glucose deprivation (OGD). Cell death in CA1, CA3 and dentate regions of the cultures was assessed 24 hours later with SYTOX(®) or propidium iodide, both of which are fluorescent markers labeling damaged cells. OGD caused extensive cell death in CA1, CA3, and dentate regions of the hippocampal cultures. Hypothermia (32°C, 23°C and 17°C) for 4-6 hours immediately after OGD was protective at 24 hours, but when hypothermia was applied for longer periods or delayed after OGD, no protection or increased death was seen. Ultra-profound hypothermia (4°C) increased cell death in all cell areas of the hippocampus even when after a milder insult of only hypoxia. In an in vitro model of recovery after an ischemia-like insult, mild to profound hypothermia is protective only when applied without delay and for limited periods of time (6-8 hours). Longer durations of hypothermia, or delayed application of the hypothermia can increase neuron death. These findings may have implications for clinical uses of therapeutic hypothermia after hypoxic or ischemic insults, and suggest that further work is needed to elucidate the limitations of hypothermia as a protective treatment after ischemic stress.

  11. 再生障碍性贫血患者PIG-A基因外显子2、4、5突变及粒细胞CD 55、CD 59的表达%Mutations of PIG-A gene Exons 2,4,5 and Granulocytic Expressions of CD55 and CD59 in Patients with Aplastic Anemia

    Institute of Scientific and Technical Information of China (English)

    李玉云; 昝丽娜; 王卫国

    2009-01-01

    背景与目的:探讨再生障碍性贫血(aplastic anemia,AA)患者PIG-A基因外显子2、4、5的突变及粒细胞表面CD55、CD59锚蛋白表达的情况. 材料与方法:从30例AA患者及20例正常对照组人群外周血提取基因组DNA,采用PCR扩增PIC-A基因外显子2、4、5,再将纯化的PCR产物双向测序检测基因序列;并用流式细胞术检测两组人群外周血粒细胞中CD55、CD59的表达. 结果:30例从患者中11例发现PIG-A基因外显子2突变,包括碱基替代、缺失、插入;PIG-A基因外显子4和外显子5突变各5例,仅为碱基替代;共5例患者有2个或2个以上外显子存在突变,正常对照组未发现突变.粒细胞CD55和CD59的表达率在AA患者PIG-A基因突变者中分别为(86.57 4±5.90)%、(88.174±5.90)%,在PIG-A基因未突变者中分别为(91.874±4.79)%、(94.24±3.76)%.均较正常对照组(97.864±1.52)%、(98.824±1.42)%显著降低(P均<0.05).结论:再生障碍性贫血患者存在PIG-A基因突变和粒细胞CD55、CD59表达缺失的现象,提示再障患者可能存在造血的克隆源性异常.%BACKGROUND AND AIM: To explore mutations of PIG-A gene exon2, exon4, exon5 and expression of CD55 and CD59 in granulocytes of patients with aplastic anemia. MATERIALS AND METHODS: Genomic DNA from peripheral blood of 30 aplastic anemia patients and 20 normal controls were extracted, and PIG-A gene exon2, exon4, exon5 were then examined with polymerase chain reaction (PCR) , nucleotide sequences were analyzed by bidirectional sequencing after PCR products were purified. The expressions of CD55 and CD59 in granulocytes from peripheral blood of the two groups above were detected by flow cytometry. RESULTS: The mutations of PIG-A gene exon2 including base substitution, deletion, insertion occurred in 11 of 30 aplastic anemia patients , the mutations of exon4, exon5 were also found in five aplastic anemia patients, with only base substitution. Two or more exon mutations were found in 5

  12. Hydroxysafflor Yellow A Protects Neurons From Excitotoxic Death through Inhibition of NMDARs

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    Xingtao Wang

    2016-04-01

    , our data demonstrate for the first time that HSYA protects hippocampal neurons from excitotoxic damage through the inhibition of NMDARs. This novel finding indicates that HSYA may be a promising pharmacological candidate for the treatment of brain ischemia.

  13. Protective roles of heat stress on the neurons in hippocampal CA1 region of mice

    Institute of Scientific and Technical Information of China (English)

    WANG Chunxu; WANG Hanxing

    2007-01-01

    The effects of heat stress on the neurons in hippocampal CA1 region of brain ischemia/reperfusion were explored.The mice were pretreated with heat stress followed by ischemia/reperfusion by clipping bilateral cervical common arteries for 7 min.Mice were divided randomly into four groups as follows:(1)normal control group;(2)heat stress pretreated subsequent to ischemia/reperfusion group (HS/IR);(3)ischemia/reperfusion group(IR);and(4)heat stress group(HS).Animals in the last three groups were subdivided into three subgroups:1 d,4 d,14 d respectively.The Morris water maze was used to test the ability of learning and memorizing,Nissl staining was used to count the average number of survived neurons in hippocampal CA1 region,and immunohistochemistry combined with image analysis system to detect the changes of Microtubule associated protein 2 (MAP-2)expression.The results showed that mice in IR group exhibited increased escape latency when compared with that of normal,HS and HS/IR groups(P<0.01),and the mice in IR group adopted an inefficient search strategy,major in circling and restricted searching manners.Nissl staining results showed a significant reduction in the number of pyramidal neurons in hippocampal CA1 regions in HS/IR and IR groups,with a decrease in IR group(P<0.01).Compared with normal group,the expression of MAP-2 in hippocampal CA1 region obviously decreased in IR group(P<0.05).The present results indicate that heat stress pretreatment can improve the spatial learning and memorizing function through protection to hippocampal neurons.

  14. Protective effects of plant seed extracts against amyloid β-induced neurotoxicity in cultured hippocampal neurons

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    Yoshinori Okada

    2013-01-01

    Full Text Available Aim: Alzheimer′s disease (AD is characterized by large deposits of amyloid β (Aβ peptide. Aβ is known to increase reactive oxygen species (ROS production in neurons, leading to cell death. In this study, we screened 15 plant seeds′ aqueous extracts (PSAE for inhibitory effects on Aβ (25-35-induced cell death using hippocampus neurons (HIPN. Materials and Methods: Fifteen chosen plants were nine medical herbs (Japanese honeywort, luffa, rapeseed, Chinese colza, potherb mustard, Japanese radish, bitter melon, red shiso, corn, and kaiware radish and six general commercial plants (common bean, komatsuna, Qing geng cai, bell pepper, kale, and lettuce. PSAE were measured for total phenolic content (TPC with the Folin-Ciocalteu method, and the 2-diphenyl-1-picryl-hydrazyl (DPPH radical scavenging effect of each seed extract was measured. To find a protectant against Aβ-induced oxidative stress, we screened 15 PSAE using a 2′, 7′-dichlorofluorescein diacetate assay. To further unravel the anti-inflammatory effects of PSAE on Aβ-induced inflammation, PSAE were added to HIPN. The neuroprotective effects of the PSAE were evaluated by Cell Counting Kit-8 assay, measuring the cell viability in Aβ-induced HIPN. Results: TPC of 15 PSAE was in the range of 0.024-1.96 mg of chlorogenic acid equivalents/gram. The aqueous extracts showed antioxidant activities. Furthermore, intracellular ROS accumulation resulting from Aβ treatment was reduced when cells were treated with some PSAE. Kale, bitter melon, kaiware radish, red shiso, and corn inhibited tumor necrosis factor-alpha secretion by the Aβ-stimulated neurons and all samples except Japanese honeywort showed enhancement of cell survival. Conclusion: From these results, we suggest that some plant seed extracts offer protection against Aβ-mediated cell death.

  15. IL-10 Protects Neurites in Oxygen-Glucose-Deprived Cortical Neurons through the PI3K/Akt Pathway.

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    Longzai Lin

    Full Text Available IL-10, as a cytokine, has an anti-inflammatory cascade following various injuries, but it remains blurred whether IL-10 protects neurites of cortical neurons after oxygen-glucose deprivation injury. Here, we reported that IL-10, in a concentration-dependent manner, reduced neuronal apoptosis and increased neuronal survival in oxygen-glucose-deprived primary cortical neurons, producing an optimal protective effect at 20ng/ml. After staining NF-H and GAP-43, we found that IL-10 significantly protected neurites in terms of axon length and dendrite number by confocal microscopy. Furthermore, it induced the phosphorylation of AKT, suppressed the activation of caspase-3, and up-regulated the protein expression of GAP-43. In contrast, LY294002, a specific inhibitor of PI3K/AKT, reduced the level of AKT phosphorylation and GAP-43 expression, increased active caspase-3 expression and thus significantly weakened IL-10-mediated protective effect in the OGD-induced injury model. IL-10NA, the IL-10 neutralizing antibody, reduced the level of p-PI3K phosphorylation and increased the expression of active caspase-3. These findings suggest that IL-10 provides neuroprotective effects by protecting neurites through PI3K/AKT signaling pathway in oxygen-glucose-deprived primary cortical neurons.

  16. Protective effects of aloperine on neonatal rat primary cultured hippocampal neurons injured by oxygen-glucose deprivation and reperfusion.

    Science.gov (United States)

    Ma, Ning-Tian; Zhou, Ru; Chang, Ren-Yuan; Hao, Yin-Ju; Ma, Lin; Jin, Shao-Ju; Du, Juan; Zheng, Jie; Zhao, Cheng-Jun; Niu, Yang; Sun, Tao; Li, Wei; Koike, Kazuo; Yu, Jian-Qiang; Li, Yu-Xiang

    2015-10-01

    Aloperine (ALO), one of the alkaloids isolated from Sophora alopecuroides L., is traditionally used for various diseases including neuronal disorders. This study investigated the protective effects of ALO on neonatal rat primary-cultured hippocampal neurons injured by oxygen-glucose deprivation and reperfusion (OGD/RP). Treatment with ALO (25, 50, and 100 mg/l) attenuated neuronal damage (p oxygen species and malondialdehyde production and enhanced the antioxidant enzymatic activities of catalase, superoxide dismutase, glutathione peroxidase and the total antioxidant capacity. The results suggested that ALO has significant neuroprotective effects that can be attributed to anti-oxidative stress.

  17. NaHS Protects against the Impairments Induced by Oxygen-Glucose Deprivation in Different Ages of Primary Hippocampal Neurons

    Science.gov (United States)

    Yu, Qian; Wang, Binrong; Zhao, Tianzhi; Zhang, Xiangnan; Tao, Lei; Shi, Jinshan; Sun, Xude; Ding, Qian

    2017-01-01

    Brain ischemia leads to poor oxygen supply, and is one of the leading causes of brain damage and/or death. Neuroprotective agents are thus in great need for treatment purpose. Using both young and aged primary cultured hippocampal neurons as in vitro models, we investigated the effect of sodium hydrosulfide (NaHS), an exogenous donor of hydrogen sulfide, on oxygen-glucose deprivation (OGD) damaged neurons that mimick focal cerebral ischemia/reperfusion (I/R) induced brain injury. NaHS treatment (250 μM) protected both young and aged hippocampal neurons, as indicated by restoring number of primary dendrites by 43.9 and 68.7%, number of dendritic end tips by 59.8 and 101.1%, neurite length by 36.8 and 66.7%, and spine density by 38.0 and 58.5% in the OGD-damaged young and aged neurons, respectively. NaHS treatment inhibited growth-associated protein 43 downregulation, oxidative stress in both young and aged hippocampal neurons following OGD damage. Further studies revealed that NaHS treatment could restore ERK1/2 activation, which was inhibited by OGD-induced protein phosphatase 2 (PP2A) upregulation. Our results demonstrated that NaHS has potent protective effects against neuron injury induced by OGD in both young and aged hippocampal neurons.

  18. Mitochondria-targeted antioxidant mitotempo protects mitochondrial function against amyloid beta toxicity in primary cultured mouse neurons.

    Science.gov (United States)

    Hu, Hongtao; Li, Mo

    2016-09-01

    Mitochondrial defects including excess reactive oxygen species (ROS) production and compromised ATP generation are featured pathology in Alzheimer's disease (AD). Amyloid beta (Aβ)-mediated mitochondrial ROS overproduction disrupts intra-neuronal Redox balance, in turn exacerbating mitochondrial dysfunction leading to neuronal injury. Previous studies have found the beneficial effects of mitochondria-targeted antioxidants in preventing mitochondrial dysfunction and neuronal injury in AD animal and cell models, suggesting that mitochondrial ROS scavengers hold promise for the treatment of this neurological disorder. In this study, we have determined that mitotempo, a novel mitochondria-targeted antioxidant protects mitochondrial function from the toxicity of Aβ in primary cultured neurons. Our results showed that Aβ-promoted mitochondrial superoxide production and neuronal lipid oxidation were significantly suppressed by the application of mitotempo. Moreover, mitotempo also demonstrated protective effects on mitochondrial bioenergetics evidenced by preserved mitochondrial membrane potential, cytochrome c oxidase activity as well as ATP production. In addition, the Aβ-induced mitochondrial DNA (mtDNA) depletion and decreased expression levels of mtDNA replication-related DNA polymerase gamma (DNA pol γ) and Twinkle were substantially mitigated by mitotempo. Therefore, our study suggests that elimination of excess mitochondrial ROS rescues mitochondrial function in Aβ-insulted neruons; and mitotempo has the potential to be a promising therapeutic agent to protect mitochondrial and neuronal function in AD.

  19. Protective effects of endoplasmic reticulum stress preconditioning on hippocampal neurons in rats with status epilepticus

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    Yi ZHANG

    2014-12-01

    Full Text Available Objective To evaluate the protective effects of endoplasmic reticulum stress preconditioning induced by 2-deoxyglucose (2-DG on hippocampal neurons of rats with status epilepticus (SE and the possible mechanism.  Methods Ninety Sprague-Dawley (SD rats were randomly enrolled into preconditioning group (N = 30, SE group (N = 30 and control group (N = 30. Each group was divided into 6 subsets (N = 5 according to six time points (before seizure, 6 h, 12 h, 1 d, 2 d and 7 d after seizure. The preconditioning group was administered 2-DG intraperitoneally with a dose of 150 mg/kg for 7 days, and the lithium-pilocarpine induced SE rat model was established on both preconditioning group and SE group. The rats were sacrificed at the above six time points, and the brains were removed to make paraffin sections. Nissl staining was performed by toluidine blue to evaluate the hippocampal neuronal damage after seizure, and the number of survival neurons in hippocampal CA1 and CA3 regions of the rats were counted. Immunohistochemical staining was performed to detect the expressions of glucose regulated protein 78 (GRP78 and X-box binding protein 1 (XBP-1 in hippocampal CA3 region of the rats.  Results The number of survival neurons in preconditioning group was much more than that in SE group at 7 d after seizure (t = 5.353, P = 0.000, and was more obvious in CA1 region. There was no significant hippocampal neuronal damage in control group. The expressions of GRP78 and XBP-1 in CA3 region of hippocampus in SE group at 6 h after seizure were significantly higher than that in control group (P = 0.000, and then kept increasing until reaching the peak at 2 d (P = 0.000, for all. The expressions of GRP78 and XBP-1 in hippocampal CA3 region in preconditioning group were significantly higher than that in control group before seizure (P = 0.000, for all. The level of GRP78 maintained the highest at 24 h and 2 d after seizure (P = 0.000, for all, while the XBP-1 level

  20. Autophagy Constitutes a Protective Mechanism against Ethanol Toxicity in Mouse Astrocytes and Neurons.

    Science.gov (United States)

    Pla, Antoni; Pascual, María; Guerri, Consuelo

    2016-01-01

    Ethanol induces brain damage and neurodegeneration by triggering inflammatory processes in glial cells through activation of Toll-like receptor 4 (TLR4) signaling. Recent evidence indicates the role of protein degradation pathways in neurodegeneration and alcoholic liver disease, but how these processes affect the brain remains elusive. We have demonstrated that chronic ethanol consumption impairs proteolytic pathways in mouse brain, and the immune response mediated by TLR4 receptors participates in these dysfunctions. We evaluate the in vitro effects of an acute ethanol dose on the autophagy-lysosome pathway (ALP) on WT and TLR4-/- mouse astrocytes and neurons in primary culture, and how these changes affect cell survival. Our results show that ethanol induces overexpression of several autophagy markers (ATG12, LC3-II, CTSB), and increases the number of lysosomes in WT astrocytes, effects accompanied by a basification of lysosomal pH and by lowered phosphorylation levels of autophagy inhibitor mTOR, along with activation of complexes beclin-1 and ULK1. Notably, we found only minor changes between control and ethanol-treated TLR4-/- mouse astroglial cells. Ethanol also triggers the expression of the inflammatory mediators iNOS and COX-2, but induces astroglial death only slightly. Blocking autophagy by using specific inhibitors increases both inflammation and cell death. Conversely, in neurons, ethanol down-regulates the autophagy pathway and triggers cell death, which is partially recovered by using autophagy enhancers. These results support the protective role of the ALP against ethanol-induced astroglial cell damage in a TLR4-dependent manner, and provide new insight into the mechanisms that underlie ethanol-induced brain damage and are neuronal sensitive to the ethanol effects.

  1. Ketogenic diet protects against epileptogenesis as well as neuronal loss in amygdaloid-kindling seizures.

    Science.gov (United States)

    Jiang, Yan; Yang, Yi; Wang, Shuang; Ding, Yao; Guo, Yi; Zhang, Man-Man; Wen, Shu-Qun; Ding, Mei-Ping

    2012-02-01

    Ketogenic diets (KD) have shown beneficial effects in terms of anticonvulsant and anti-epileptogenic properties in several experimental models. However, few studies have investigated the consequences of KD with regards to the anti-epileptogenic and neuroprotective effects in kindling-induced seizures. Here, postnatal day 28 male Sprague-Dawley rats received one of two experimental diets for 4 weeks: (a) a 'classic' 4:1 KD; and (b) a normal regular rodent chow diet (ND). Fully-kindled seizures were achieved by daily electrical stimulation in the amygdala. Seizure stage and after-discharge duration (ADD) were assessed daily. The after-discharge threshold (ADT) was measured every 5 days. The effects of the two diets on neuronal loss were observed before kindling and 20 days after stimulation by Nissl staining. We found that the progression of seizure stage and ADD was delayed by KD. KD prevented the ADT decrease on day 5. The incidence of generalized seizures was lower in the KD group compared to the ND group. The neuronal density was decreased in the ipsilateral hilus of the dentate gyrus (DG) and CA1 area, as well as the contralateral CA1 area before kindling in the KD group. However, KD prevented neuronal loss in the ipsilateral CA1 area 20 days after stimulation. Our data suggest that KD can protect against epileptogenesis by preventing both after-discharge generation and propagation in kindling seizures. In addition, KD also possesses a neuroprotective function during kindling although it changes hippocampal development in early life.

  2. Schisandrin B protects rat cortical neurons against Abeta1-42-induced neurotoxicity.

    Science.gov (United States)

    Wang, Bin; Wang, Xue-Mei

    2009-07-01

    In the present study, we investigated the neuroprotective effects of schisandrin B on amyloid-beta1-42-induced toxicity and its potential mechanisms in rat cortical neuron cells. Amyloid beta1-42 significantly reduced cell viability and increased apoptosis. Pretreatment with schisandrin B prior to amyloid-beta1-42 exposure significantly elevated cell viability and reduced apoptosis. The anti-apoptotic effect of schisandrin B in rat cortical neurons was mediated by up-regulation of the anti-apoptotic protein Bcl-2 and down-regulation of the pro-apoptotic protein Bax. Schisandrin B also reduced the release of mitochondrial cytochrome c into cytosol and decreased caspase-9 and caspase-3 activities. Furthermore, schisandrin B increased activities of anti-oxidant reduced glutathione and decreased production of oxidative glutathione. Taken together, these results suggest that schisandrin B protected primary cultures of rat cortical cells against amyloid-beta1-42-induced neurotoxicity through anti-apoptosis involved in a mitochondria-mediated pathway and anti-oxidant action. Schisandrin B may represent a potential treatment strategy for Alzheimer's disease.

  3. Phenolic Compounds Protect Cultured Hippocampal Neurons against Ethanol-Withdrawal Induced Oxidative Stress

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    Marianna E. Jung

    2009-04-01

    Full Text Available Ethanol withdrawal is linked to elevated oxidative damage to neurons. Here we report our findings on the contribution of phenolic antioxidants (17β-estradiol, p-octyl-phenol and 2,6-di-tert-butyl-4-methylphenol to counterbalance sudden ethanol withdrawal-initiated oxidative events in hippocampus-derived cultured HT-22 cells. We showed that ethanol withdrawal for 4 h after 24-h ethanol treatment provoked greater levels of oxidative damage than the preceding ethanol exposure. Phenolic antioxidant treatment either during ethanol exposure or ethanol withdrawal only, however, dose-dependently reversed cellular oxidative damage, as demonstrated by the significantly enhanced cell viability, reduced malondialdehyde production and protein carbonylation, compared to untreated cells. Interestingly, the antioxidant treatment schedule had no significant impact on the observed neuroprotection. In addition, the efficacy of the three phenolic compounds was practically equipotent in protecting HT-22 cells in spite of predictions based on an in silico study and a cell free assay of lipid peroxidation. This finding implies that free-radical scavenging may not be the sole factor responsible for the observed neuroprotection and warrants further studies to establish, whether the HT-22 line is indeed a suitable model for in vitro screening of antioxidants against EW-related neuronal damage.

  4. Topiramate protects against glutamate excitotoxicity via activating BDNF/TrkB-dependent ERK pathway in rodent hippocampal neurons.

    Science.gov (United States)

    Mao, Xiao-Yuan; Cao, Yong-Gang; Ji, Zhong; Zhou, Hong-Hao; Liu, Zhao-Qian; Sun, Hong-Li

    2015-07-01

    Topiramate (TPM) was previously found to have neuroprotection against neuronal injury in epileptic and ischemic models. However, whether TPM protects against glutamate-induced excitotoxicity in hippocampal neurons is elusive. Our present work aimed to evaluate the protective effect of TPM against glutamate toxicity in hippocampal neurons and further figure out the potential molecular mechanisms. The in vitro glutamate excitotoxic model was prepared with 125μM glutamate for 20min. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) analysis and Hoechst 33342 staining were conducted to detect neuronal survival. The protein expressions of brain-derived neurotrophic factor (BDNF), TrkB, mitogen-activated protein kinase (MAPK) cascade (including extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK) and p38 MAPK), cyclic AMP response element binding protein (CREB), Bcl-2, Bax and β-actin were detected via Western blot assay. Our results demonstrated that TPM protected hippocampal neurons from glutamate toxicity. Meanwhile, the pretreatment of TPM for 10min significantly prevented the down-regulation of BDNF and the phosphorylation of TrkB. Furthermore, the elevation of phosphorylated EKR expression was significantly inhibited after blockade of TrkB by TrkB IgG, while no alterations of phosphorylated JNK and p38 MAPK were found in the cultured hippocampal neurons. Besides, it was also found that the enhanced phosphorylation of CREB was evidently reversed under excitotoxic conditions after treating with U0126 (the selective inhibitor of ERK). The protein level of Bcl-2 was also observed to be remarkably increased after TPM treatment. In conclusion, these findings implicate that TPM exerts neuroprotective effects against glutamate excitotoxicity in hippocampal neurons and its protection may be modulated through BDNF/TrkB-dependent ERK pathway.

  5. carboxypeptidase E-ΔN, a neuroprotein transiently expressed during development protects embryonic neurons against glutamate neurotoxicity.

    Directory of Open Access Journals (Sweden)

    Xiao-Yan Qin

    Full Text Available Neuroprotective proteins expressed in the fetus play a critical role during early embryonic neurodevelopment, especially during maternal exposure to alcohol and drugs that cause stress, glutamate neuroexcitotoxicity, and damage to the fetal brain, if prolonged. We have identified a novel protein, carboxypeptidase E-ΔN (CPE-ΔN, which is a splice variant of CPE that has neuroprotective effects on embryonic neurons. CPE-ΔN is transiently expressed in mouse embryos from embryonic day 5.5 to postnatal day 1. It is expressed in embryonic neurons, but not in 3 week or older mouse brains, suggesting a function primarily in utero. CPE-ΔN expression was up-regulated in embryonic hippocampal neurons in response to dexamethasone treatment. CPE-ΔN transduced into rat embryonic cortical and hippocampal neurons protected them from glutamate- and H2O2-induced cell death. When transduced into embryonic cortical neurons, CPE-ΔN was found in the nucleus and enhanced the transcription of FGF2 mRNA. Embryonic cortical neurons challenged with glutamate resulted in attenuated FGF2 levels and cell death, but CPE-ΔN transduced neurons treated in the same manner showed increased FGF2 expression and normal viability. This neuroprotective effect of CPE-ΔN was mediated by secreted FGF2. Through receptor signaling, FGF2 activated the AKT and ERK signaling pathways, which in turn increased BCL-2 expression. This led to inhibition of caspase-3 activity and cell survival.

  6. Intravenous immunoglobulin protects neurons against amyloid beta-peptide toxicity and ischemic stroke by attenuating multiple cell death pathways.

    Science.gov (United States)

    Widiapradja, Alexander; Vegh, Viktor; Lok, Ker Zhing; Manzanero, Silvia; Thundyil, John; Gelderblom, Mathias; Cheng, Yi-Lin; Pavlovski, Dale; Tang, Sung-Chun; Jo, Dong-Gyu; Magnus, Tim; Chan, Sic L; Sobey, Christopher G; Reutens, David; Basta, Milan; Mattson, Mark P; Arumugam, Thiruma V

    2012-07-01

    Intravenous immunoglobulin (IVIg) preparations obtained by fractionating blood plasma, are increasingly being used increasingly as an effective therapeutic agent in treatment of several inflammatory diseases. Its use as a potential therapeutic agent for treatment of stroke and Alzheimer's disease has been proposed, but little is known about the neuroprotective mechanisms of IVIg. In this study, we investigated the effect of IVIg on downstream signaling pathways that are involved in neuronal cell death in experimental models of stroke and Alzheimer's disease. Treatment of cultured neurons with IVIg reduced simulated ischemia- and amyloid βpeptide (Aβ)-induced caspase 3 cleavage, and phosphorylation of the cell death-associated kinases p38MAPK, c-Jun NH2 -terminal kinase and p65, in vitro. Additionally, Aβ-induced accumulation of the lipid peroxidation product 4-hydroxynonenal was attenuated in neurons treated with IVIg. IVIg treatment also up-regulated the anti-apoptotic protein, Bcl2 in cortical neurons under ischemia-like conditions and exposure to Aβ. Treatment of mice with IVIg reduced neuronal cell loss, apoptosis and infarct size, and improved functional outcome in a model of focal ischemic stroke. Together, these results indicate that IVIg acts directly on neurons to protect them against ischemic stroke and Aβ-induced neuronal apoptosis by inhibiting cell death pathways and by elevating levels of the anti-apoptotic protein Bcl2.

  7. Basic fibroblast growth factor protects auditory neurons and hair cells from noise exposure and glutamate neurotoxicity

    Institute of Scientific and Technical Information of China (English)

    翟所强; 王大君; 王嘉陵

    2003-01-01

    The purpose of the present study was to determine protectivie effects of basic fibroblast growth factor (bFGF) on cochlear neurons and hair cells in vitro and in vivo. In experiment I, cultured spiral ganglion neurons (SGNs) prepared from P3 mice were exposed to 20mM glutamate for 2 hours before the culture medium was replaced with fresh medium containing 0, 25, 50, and 100 ng/ml bFGF, respectively. Fourteen days later, all cultures were fixed with 4% paraformaldehyde, and stained with 1% toluidine blue. The number of surviving SGNs were counted and the length of SGNs neurites were measured. Exposure to 20 mM glutamate for 24 hours resulted in an inhibition on neurite outgrowth of SGNs and elevated cell death. Treatment of the cultures with bFGF led to promotion of neurite outgrowth and elevated number of surviving SGNs. Effects of bFGF were dose dependent with the highest potency at 100 ng/ml. In experiment Ⅱ, in vivo studies were carried out with guinea pigs in which bFGF or artificial perilymph was perfused into the cochlea to assess possible protective effects of bFGF on cochlear hair cells and compound action potentials(CAP). The CAPs were measured before, immediatly and 48 hours after exposure to noise. Significant differences in CAP were observed (p<0. 05 ) among the bFGF perfused group, control group(t =3. 896 ) and artificial perilymph perfused group (t =2. 520) at 48 hours after noise exposure, Cochleae were removed and hair cell Loss was analyzed in surface preparations prepared from all experimental animals. Acoustic trauma caused loss of 651 and 687 inner hair cells in the control and artificial perilymph perfused group, respectively. In sharp contrast, only 31 inner hair cells were lost in the bFGF perfused ears. Similarly, more outer hair cells died in the control and perilymph perfuesed group (41830 and 41968, respectively) than in the group treated with bFGF (34258). Our results demonstrate that bFGF protected SGNs against glutmate

  8. 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.

  9. Geniposide Protects Primary Cortical Neurons against Oligomeric Aβ1-42-Induced Neurotoxicity through a Mitochondrial Pathway.

    Directory of Open Access Journals (Sweden)

    Chunhui Zhao

    Full Text Available Mitochondrial dysfunction plays a key role in the progression of Alzheimer's disease (AD. The accumulation of amyloid-beta peptide (Aβ in the brains of AD patients is thought to be closely related to neuronal mitochondrial dysfunction and oxidative stress. Therefore, protecting mitochondria from Aβ-induced neurotoxicity is an effective strategy for AD therapeutics. In a previous study, we found that geniposide, a pharmacologically active compound purified from gardenia fruit, has protective effects on oxidative stress and mitochondrial dysfunction in AD transgenic mouse models. However, whether geniposide has a protective effect on Aβ-induced neuronal dysfunction remains unknown. In the present study, we demonstrate that geniposide protects cultured primary cortical neurons from Aβ-mediated mitochondrial dysfunction by recovering ATP generation, mitochondrial membrane potential (MMP, and cytochrome c oxidase (CcO and caspase 3/9 activity; by reducing ROS production and cytochrome c leakage; as well as by inhibiting apoptosis. These findings suggest that geniposide may attenuate Aβ-induced neuronal injury by inhibiting mitochondrial dysfunction and oxidative stress.

  10. Role of hippocampal dentate gyrus neurons in the protective effects of heat shock factor 1 on working memory

    Institute of Scientific and Technical Information of China (English)

    Min Peng; Xiongzhao Zhu; Ming Cheng; Xiangyi Chen; Shuqiao Yao

    2011-01-01

    Increasing evidence suggests that heat shock factor 1 exerts endogenous protective effects on working memory under conditions of chronic psychological stress. However, the precise underlying mechanisms remain poorly understood. This study examined the protective factors affecting working memory in heat shock transcription factor 1 gene knockout mice. The results indicated that the number of correct T maze alternations decreased following mild chronic psychological stress in knockout mice. This change was accompanied by a decrease in neurogenesis and an increase in neuronal apoptosis in the hippocampal dentate gyrus. The number of correct T maze alternations was positively correlated with neurogenesis in hippocampal dentate gyrus, and negatively correlated with neuronal apoptosis. In wild type mice, no significant difference was detected in the number of correct T maze alternations or neuronal apoptosis in hippocampal dentate gyrus. These results indicate that the heat shock factor 1 gene has an endogenous protective role in working memory during mild chronic psychological stress associated with dentate gyrus neuronal apoptosis.Moreover, dentate gyrus neurogenesis appears to participate in the protective mechanism.

  11. Delayed translocation of NGFI-B/RXR in glutamate stimulated neurons allows late protection by 9-cis retinoic acid

    Energy Technology Data Exchange (ETDEWEB)

    Mathisen, Gro H.; Fallgren, Asa B.; Strom, Bjorn O.; Boldingh Debernard, Karen A.; Mohebi, Beata U. [Department of Pharmaceutical Biosciences, University of Oslo, P.O. Box 1068, Blindern, N-0316 Oslo (Norway); Paulsen, Ragnhild E., E-mail: r.e.paulsen@farmasi.uio.no [Department of Pharmaceutical Biosciences, University of Oslo, P.O. Box 1068, Blindern, N-0316 Oslo (Norway)

    2011-10-14

    Highlights: {yields} NGFI-B and RXR translocate out of the nucleus after glutamate treatment. {yields} Arresting NGFI-B/RXR in the nucleus protects neurons from excitotoxicity. {yields} Late protection by 9-cis RA is possible due to a delayed translocation of NGFI-B/RXR. -- Abstract: Nuclear receptor and apoptosis inducer NGFI-B translocates out of the nucleus as a heterodimer with RXR in response to different apoptosis stimuli, and therefore represents a potential pharmacological target. We found that the cytosolic levels of NGFI-B and RXR{alpha} were increased in cultures of cerebellar granule neurons 2 h after treatment with glutamate (excitatory neurotransmitter in the brain, involved in stroke). To find a time-window for potential intervention the neurons were transfected with gfp-tagged expressor plasmids for NGFI-B and RXR. The default localization of NGFI-Bgfp and RXRgfp was nuclear, however, translocation out of the nucleus was observed 2-3 h after glutamate treatment. We therefore hypothesized that the time-window between treatment and translocation would allow late protection against neuronal death. The RXR ligand 9-cis retinoic acid was used to arrest NGFI-B and RXR in the nucleus. Addition of 9-cis retinoic acid 1 h after treatment with glutamate reduced the cytosolic translocation of NGFI-B and RXR{alpha}, the cytosolic translocation of NGFI-Bgfp observed in live neurons, as well as the neuronal death. However, the reduced translocation and the reduced cell death were not observed when 9-cis retinoic acid was added after 3 h. Thus, late protection from glutamate induced death by addition of 9-cis retinoic acid is possible in a time-window after apoptosis induction.

  12. Protective effect of Angelica sinensis on cerebral neurons from rat embryos under hypoxia

    Institute of Scientific and Technical Information of China (English)

    Yuling Wu; Hongxian Zhao; Hong Yu

    2007-01-01

    BACKGROUND: The enhanced expression of c-Fos protein in nerve cells after hypoxia is the marker for converting extracellular hypoxia information to intracellular changes at hypoxia, and it is suspected that the increase of c-Fos protein can lead to the synthesis and excretion of related neurotrophic factor and nerve growth factor. However, it is still unclear what functional changes of nerve cells are induced by the increase of c-Fos protein at hypoxia, and whether it is good for the survival of damaged neurons.OBJECTIVE: To observe the expression of c-Fos in the cerebral neurons from embryos of rats with hypoxia in uterus, and investigate the pathway for the protective effect of Angelica sinensis injection on the cerebral neurons from rat embryos under hypoxia.DESIGN: A completely randomized controlled study.SETTING: Department of Histology and Embryology, Luzhou Medical College.MATERIALS: Twelve female Wistar rats in oestrum and 1 male adult Wistar rat with body mass of 220 to 250 g were selected. Rabbit-anti-rat neuro-specific enolase (NSE) and rabbit-anti-rat c-Fos were purchased from Wuhan Boster Biological Technology Co., Ltd.; Double-staining kit was bought from Beijing Zhongshan Golden Bridge Biotechnology Co., Ltd. Angelica sinensis injection was produced by the Department of Pharmacy, the Second Affiliated Hospital of Hubei Medical University.METHODS: The experiments were completed in the experimental animal center and the Department of Histology and Embryology of Luzhou Medical College from December 2004 to December 2005. ① Twelve adult female Wistar rats in oestrum and 1 male Wistar rat were housed in one rearing cage. The appearance of vaginal embolus at 8:00 in the next morning was recorded as 0 day of pregnancy and the rats were recorded for 15 days, and they were divided randomly into three groups, control group (n =4), hypoxia group (n =4)and Angelica group (n =4). The pregnant rats in the hypoxia group were firstly injected with saline (8 m

  13. Tamoxifen mediated estrogen receptor activation protects against early impairment of hippocampal neuron excitability in an oxygen/glucose deprivation brain slice ischemia model

    OpenAIRE

    Zhang, Huaqiu; Xie, Minjie; Gary P. Schools; Feustel, Paul F.; Wang, Wei; Lei, Ting; Kimelberg, Harold K.; Zhou, Min

    2008-01-01

    Pretreatment of ovarectomized rats with estrogen shows long-term protection via activation of the estrogen receptor (ER). However, it remains unknown whether activation of the ER can provide protection against early neuronal damage when given acutely, we simulated ischemic conditions by applying oxygen and glucose deprived (OGD) solution to acute male rat hippocampal slices and examined the neuronal electrophysiological changes. Pyramidal neurons and interneurons showed a time-dependent membr...

  14. Estrogen protects neuronal cells from amyloid beta-induced apoptosis via regulation of mitochondrial proteins and function

    Directory of Open Access Journals (Sweden)

    Iwamoto Sean

    2006-11-01

    Full Text Available Abstract Background Neurodegeneration in Alzheimer's disease is associated with increased apoptosis and parallels increased levels of amyloid beta, which can induce neuronal apoptosis. Estrogen exposure prior to neurotoxic insult of hippocampal neurons promotes neuronal defence and survival against neurodegenerative insults including amyloid beta. Although all underlying molecular mechanisms of amyloid beta neurotoxicity remain undetermined, mitochondrial dysfunction, including altered calcium homeostasis and Bcl-2 expression, are involved in neurodegenerative vulnerability. Results In this study, we investigated the mechanism of 17β-estradiol-induced prevention of amyloid beta-induced apoptosis of rat hippocampal neuronal cultures. Estradiol treatment prior to amyloid beta exposure significantly reduced the number of apoptotic neurons and the associated rise in resting intracellular calcium levels. Amyloid beta exposure provoked down regulation of a key antiapoptotic protein, Bcl-2, and resulted in mitochondrial translocation of Bax, a protein known to promote cell death, and subsequent release of cytochrome c. E2 pretreatment inhibited the amyloid beta-induced decrease in Bcl-2 expression, translocation of Bax to the mitochondria and subsequent release of cytochrome c. Further implicating the mitochondria as a target of estradiol action, in vivo estradiol treatment enhanced the respiratory function of whole brain mitochondria. In addition, estradiol pretreatment protected isolated mitochondria against calcium-induced loss of respiratory function. Conclusion Therefore, we propose that estradiol pretreatment protects against amyloid beta neurotoxicity by limiting mitochondrial dysfunction via activation of antiapoptotic mechanisms.

  15. Potential protection of green tea polyphenols against 1800 MHz electromagnetic radiation-induced injury on rat cortical neurons.

    Science.gov (United States)

    Liu, Mei-Li; Wen, Jian-Qiang; Fan, Yu-Bo

    2011-10-01

    Radiofrequency electromagnetic fields (EMF) are harmful to public health, but the certain anti-irradiation mechanism is not clear yet. The present study was performed to investigate the possible protective effects of green tea polyphenols against electromagnetic radiation-induced injury in the cultured rat cortical neurons. In this study, green tea polyphenols were used in the cultured cortical neurons exposed to 1800 MHz EMFs by the mobile phone. We found that the mobile phone irradiation for 24 h induced marked neuronal cell death in the MTT (3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyl-tetrazolium bromide) and TUNEL (TdT mediated biotin-dUTP nicked-end labeling) assay, and protective effects of green tea polyphenols on the injured cortical neurons were demonstrated by testing the content of Bcl-2 Assaciated X protein (Bax) in the immunoprecipitation assay and Western blot assay. In our study results, the mobile phone irradiation-induced increases in the content of active Bax were inhibited significantly by green tea polyphenols, while the contents of total Bax had no marked changes after the treatment of green tea polyphenols. Our results suggested a neuroprotective effect of green tea polyphenols against the mobile phone irradiation-induced injury on the cultured rat cortical neurons.

  16. Transgenic expression and activation of PGC-1α protect dopaminergic neurons in the MPTP mouse model of Parkinson's disease.

    Science.gov (United States)

    Mudò, Giuseppa; Mäkelä, Johanna; Di Liberto, Valentina; Tselykh, Timofey V; Olivieri, Melania; Piepponen, Petteri; Eriksson, Ove; Mälkiä, Annika; Bonomo, Alessandra; Kairisalo, Minna; Aguirre, Jose A; Korhonen, Laura; Belluardo, Natale; Lindholm, Dan

    2012-04-01

    Mitochondrial dysfunction and oxidative stress occur in Parkinson's disease (PD), but little is known about the molecular mechanisms controlling these events. Peroxisome proliferator-activated receptor-gamma coactivator-1α (PGC-1α) is a transcriptional coactivator that is a master regulator of oxidative stress and mitochondrial metabolism. We show here that transgenic mice overexpressing PGC-1α in dopaminergic neurons are resistant against cell degeneration induced by the neurotoxin MPTP. The increase in neuronal viability was accompanied by elevated levels of mitochondrial antioxidants SOD2 and Trx2 in the substantia nigra of transgenic mice. PGC-1α overexpression also protected against MPTP-induced striatal loss of dopamine, and mitochondria from PGC-1α transgenic mice showed an increased respiratory control ratio compared with wild-type animals. To modulate PGC-1α, we employed the small molecular compound, resveratrol (RSV) that protected dopaminergic neurons against the MPTP-induced cell degeneration almost to the same extent as after PGC-1α overexpression. As studied in vitro, RSV activated PGC-1α in dopaminergic SN4741 cells via the deacetylase SIRT1, and enhanced PGC-1α gene transcription with increases in SOD2 and Trx2. Taken together, the results reveal an important function of PGC-1α in dopaminergic neurons to combat oxidative stress and increase neuronal viability. RSV and other compounds acting via SIRT1/PGC-1α may prove useful as neuroprotective agents in PD and possibly in other neurological disorders.

  17. Krebs Cycle Intermediates Protective against Oxidative Stress by Modulating the Level of Reactive Oxygen Species in Neuronal HT22 Cells.

    Science.gov (United States)

    Sawa, Kenta; Uematsu, Takumi; Korenaga, Yusuke; Hirasawa, Ryuya; Kikuchi, Masatoshi; Murata, Kyohei; Zhang, Jian; Gai, Xiaoqing; Sakamoto, Kazuichi; Koyama, Tomoyuki; Satoh, Takumi

    2017-03-16

    Krebs cycle intermediates (KCIs) are reported to function as energy substrates in mitochondria and to exert antioxidants effects on the brain. The present study was designed to identify which KCIs are effective neuroprotective compounds against oxidative stress in neuronal cells. Here we found that pyruvate, oxaloacetate, and α-ketoglutarate, but not lactate, citrate, iso-citrate, succinate, fumarate, or malate, protected HT22 cells against hydrogen peroxide-mediated toxicity. These three intermediates reduced the production of hydrogen peroxide-activated reactive oxygen species, measured in terms of 2',7'-dichlorofluorescein diacetate fluorescence. In contrast, none of the KCIs-used at 1 mM-protected against cell death induced by high concentrations of glutamate-another type of oxidative stress-induced neuronal cell death. Because these protective KCIs did not have any toxic effects (at least up to 10 mM), they have potential use for therapeutic intervention against chronic neurodegenerative diseases.

  18. Krebs Cycle Intermediates Protective against Oxidative Stress by Modulating the Level of Reactive Oxygen Species in Neuronal HT22 Cells

    Directory of Open Access Journals (Sweden)

    Kenta Sawa

    2017-03-01

    Full Text Available Krebs cycle intermediates (KCIs are reported to function as energy substrates in mitochondria and to exert antioxidants effects on the brain. The present study was designed to identify which KCIs are effective neuroprotective compounds against oxidative stress in neuronal cells. Here we found that pyruvate, oxaloacetate, and α-ketoglutarate, but not lactate, citrate, iso-citrate, succinate, fumarate, or malate, protected HT22 cells against hydrogen peroxide-mediated toxicity. These three intermediates reduced the production of hydrogen peroxide-activated reactive oxygen species, measured in terms of 2′,7′-dichlorofluorescein diacetate fluorescence. In contrast, none of the KCIs—used at 1 mM—protected against cell death induced by high concentrations of glutamate—another type of oxidative stress-induced neuronal cell death. Because these protective KCIs did not have any toxic effects (at least up to 10 mM, they have potential use for therapeutic intervention against chronic neurodegenerative diseases.

  19. TIMP1 in conditioned media of human adipose stromal cells protects neurons against oxygen-glucose deprivation injury.

    Science.gov (United States)

    Du, Shiwei; Mao, Gengsheng; Zhu, Timothy; Luan, Zuo; Du, Yansheng; Gu, Huiying

    2015-01-01

    Adipose stromal cells (ASC) can protect neurons when administered to brains due to secreted trophic factors. Our previous studies demonstrated that several neurotrophic factors such as brain-derived neurotropic factor (BDNF) and insulin like growth factor-1 (IGF-1) in ASC conditioned media (ASC-CM) can protect brains against hypoxic-ischemic (HI) injury in neonatal rats. In this study, we demonstrated that human ASC-CM potently blockeds caspase-3 mediated cortical neuronal apoptosis under in vitro oxygen-glucose deprivation (OGD). Interestingly, tissue inhibitor of metalloproteinase 1 (TIMP1), a non neurotrophic factor, played a significant role in the ASC-CM-induced neural protection against OGD. Thus, this study establishes the therapeutic potential of TIMP1 together with other neurotrophic factors in ASC-CM for treating cerebral HI disorders.

  20. Underlying mechanism of protection from hypoxic injury seen with n-butanol extract of Potentilla anserine L. in hippocampal neurons

    Institute of Scientific and Technical Information of China (English)

    Xiaojing Qin; Lingzhi Li; Qi Lv; Baoguo Yu; Shuwang Yang; Tao He; Yongliang Zhang

    2012-01-01

    The alcohol and n-butanol extract of Potentilla anserine L.significantly protects myocardium from acute ischemic injury.However,its effects on rat hippocampal neurons and the mechanism of protection remain unclear.In this study,primary cultured hippocampal neurons from neonatal rats were incubated in 95% N2 and 5% CO2 for 4 hours.Results indicated that hypoxic injury decreased the viability of neurons,increased the expression levels of caspase-9 and caspase-3 mRNA,as well as cytochrome c,Caspase-9,and Caspase-3 protein.Pretreatment with 0.25,0.0625,0.0156 mg/mL n-butanol extract of Potentilla anserine L.led to a significant increase in cell viability.Expression levels of caspase-9 and caspase-3 mRNA,as well as cytochrome c,Caspase-9,andCaspase-3 protein,were attenuated.The neuroprotective effect of n-butanol extract of Potentillaanserine L.was equivalent to tanshinone IIA.Our data suggest that the n-butanol extract of Potentilla anserine L.could protect primary hippocampal neurons from hypoxic injury by deactivating mitochondrial cell death.

  1. Glucagon-like peptide-1 protects hippocampal neurons against advanced glycation end product-induced tau hyperphosphorylation.

    Science.gov (United States)

    Chen, S; An, F-M; Yin, L; Liu, A-R; Yin, D-K; Yao, W-B; Gao, X-D

    2014-01-03

    We have previously demonstrated that glucagon-like peptide-1 (GLP-1) receptor agonist ameliorated neurodegenerative changes in rat models of diabetes-related Alzheimer's disease (AD), and protected neurons from glucose toxicity in vitro. Herein, we investigated the effects of GLP-1 receptor mediates on cell toxicity and tau hyperphosphorylation induced by advanced glycation end products (AGEs), which are associated with glucose toxicity, and the molecular mechanism in PC12 cells and the primary hippocampal neurons. Our study demonstrated that the similar protection effects of GLP-1 existed in PC12 cells treated with glucose-bovine serum albumin (BSA) in hyperglycemic conditions or with glycoaldehyde-BSA alone. Additionally, glucose-BSA alone did not induce significant cytotoxicity in PC12 cells, but resulted in tau hyperphosphorylation in primary hippocampal neurons in 24h. And we found that GLP-1 could reduce cell tau phosphorylation induced by high glucose or glucose-BSA. Furthermore, our data in the present study suggested that GLP-1 regulated tau phosphorylation induced by AGEs through a signaling pathway involving glycogen synthase kinase 3β (GSK-3β), similarly to the GSK-3β inhibitor, lithium chloride. Our findings suggest that GLP-1 can protect neurons from diabetes-associated AGE insults in vitro, and provide new evidence for a potential therapeutic value of GLP-1 receptor agonist in the treatment of AD especially diabetes-related AD.

  2. Protective mechanisms of microRNA-27a against oxygen-glucose deprivation-induced injuries in hippocampal neurons

    Institute of Scientific and Technical Information of China (English)

    Qun Cai; Ting Wang; Wen-jie Yang; Xing Fen

    2016-01-01

    Hypoxic injuries during fetal distress have been shown to cause reduced expression of microRNA-27a (miR-27a), which regulates sensi-tivity of cortical neurons to apoptosis. We hypothesized that miR-27a overexpression attenuates hypoxia-and ischemia-induced neuronal apoptosis by regulating FOXO1, an important transcription factor for regulating the oxidative stress response. miR-27a mimic was transfected into hippocampal neurons to overexpress miR-27a. Results showed increased hippocampal neuronal viability and decreased caspase-3 ex-pression. The luciferase reporter gene system demonstrated that miR-27a directly binded to FOXO1 3′UTR in hippocampal neurons and inhibited FOXO1 expression, suggesting that FOXO1 was the target gene for miR-27a. These ifndings conifrm that miR-27a protects hippo-campal neurons against oxygen-glucose deprivation-induced injuries. The mechanism might be mediated by modulation of FOXO1 and apoptosis-related gene caspase-3 expression.

  3. Protection of neuronal cells from excitotoxicity by disrupting nNOS-PSD95 interaction with a small molecule SCR-4026.

    Science.gov (United States)

    Mo, Shi-Fu; Liao, Gao-Yong; Yang, Jie; Wang, Meng-Yu; Hu, Yang; Lian, Guo-Ning; Kong, Ling-Dong; Zhao, Yong

    2016-10-01

    Stroke is a major public health problem leading to high rates of death and disability in adults. Coupling of postsynaptic density protein-95 (PSD-95) and neuronal nitric oxide synthase (nNOS) plays an important part in neuronal damage caused by stroke. Recent studies suggest the possibility of alleviating post ischemia neuron damage by blocking ischemia-induced nNOS-PSD-95 association. Here, we report a small-molecular inhibitor of nNOS-PSD-95 interaction, SCR-4026, which exhibits neuroprotective activities in NMDA-induced or Oxygen and glucose deprivation (OGD)-induced neuronal damage in primary cortical neurons cultures, and ameliorated focal cerebral ischemic damage in rats subjected to middle cerebral artery occlusion (MCAO) and reperfusion. Furthermore, we found that SCR-4026 was also able to promote neural stem cells to differentiate into neurons-like cells, which is potentially of great significance for neural protection. Taken together, SCR-4026 is identified as a novel small molecule that shows great potential in treating stroke.

  4. Protective effects of gastrodine on dendritic spines in kainic acid-injured neurons

    Institute of Scientific and Technical Information of China (English)

    Yangfei Ji; Boai Zhang; Yanjie Jia; Guifang Sun; Yu Liu; Tao Peng; Yanru Liu; Xingrong Ma

    2011-01-01

    EphB2 affects neuronal cells by altering the dendritic spines. The present study analyzed the neuroprotective effects of gastrodine by measuring EphB2 expression in rat neural cells cultured in vitro and injured by kainic acid. Gastrodine (12.5, 25, and 50 mg/L) improved morphology in kainic acid-injured neurons, reduced lactate dehydrogenase leakage, decreased neuronal apoptosis, and increased EphB2 expression in neuronal cells. A moderate dose of 25 mg/L gastrodine resulted in the most significant effects. These results suggested that gastrodine suppressed the neurotoxic effects of excitatory amino acids and provided neuroprotection by remodeling neuronal dendritic spines.

  5. Existence of glia mitigated ketamine-induced neurotoxicity in neuron-glia mixed cultures of neonatal rat cortex and the glia-mediated protective effect of 2-PMPA.

    Science.gov (United States)

    Zuo, Daiying; Wang, Chengna; Li, Zengqiang; Lin, Li; Duan, Zhenfang; Qi, Huan; Li, Lin; Sun, Feng; Wu, Yingliang

    2014-09-01

    The present study compared ketamine-induced neurotoxicity in the neuron-glia mixed cultures and neuronal cultures and further explored the neuroprotective effect of the NAAG peptidase inhibitor 2-(phosphonomethyl) pentanedioic acid (2-PMPA). Firstly, Rosenfeld's staining and immunofluorescence staining of microtubule-associated protein 2 (MAP2) and glial fibrillary acidic protein (GFAP) were used to address the difference of morphology in the mixed cultures and neuronal cultures. Our results showed that neurons and astrocytes grew in good conditions. The ratio of neurons and astrocytes in the mixed cultures was around 1:1, and the purity of neurons in the neuronal cultures is 91.3%. Furthermore, ketamine was used to test the hypothesis that the presence of a higher proportion of glia in the mixed cultures would be protective against ketamine-induced neurotoxicity in the mixed cultures compared with neuronal cultures. The results showed that ketamine-induced morphological changes, cell viability decrease and lactate dehydrogenase (LDH) levels increase were significantly mitigated in neuron-glia mixed cultures compared with neuronal cultures. Furthermore, 2-PMPA was included to further explore efficient protective drug for ketamine-induced neurotoxicity. Our results showed that 2-PMPA reduced ketamine-induced decrease of cell viability and increase of LDH levels in the mixed cultures but not in the neuronal cultures. Further morphological changes of neurons and astrocytes also indicated that 2-PMPA could improve ketamine damaged neurons in the mixed cultures instead of neuronal cultures. These results indicate that glia protect neurons from ketamine-induced neurotoxicity. These data further suggest that glia mediate the neuroprotective effect of 2-PMPA and 2-PMPA has the potential to treat ketamine-induced neurotoxicity in vivo. Delineating the mechanisms underlying the communication between neurons and glia and the neuroprotective effects of 2-PMPA in the mixed

  6. Spongionella Secondary Metabolites Protect Mitochondrial Function in Cortical Neurons against Oxidative Stress

    Directory of Open Access Journals (Sweden)

    Marta Leirós

    2014-01-01

    Full Text Available The marine habitat provides a large number of structurally-diverse bioactive compounds for drug development. Marine sponges have been studied over many years and are found to be a rich source of these bioactive chemicals. This study is focused on the evaluation of the activity of six diterpene derivatives isolated from Spongionella sp. on mitochondrial function using an oxidative in vitro stress model. The test compounds include the Gracilins (A, H, K, J and L and tetrahydroaplysulphurin-1. Compounds were co-incubated with hydrogen peroxide for 12 hours to determine their protective capacities and their effect on markers of apoptosis and Nrf2/ARE pathways was evaluated. Results conclude that Gracilins preserve neurons against oxidative damage, and that in particular, tetrahydroaplysulphurin-1 shows a complete neuroprotective activity. Oxidative stress is linked to mitochondrial dysfunction and consequently to neurodegenerative disorders like Parkinson and Alzheimer diseases, Friedreich ataxia or Amyotrophic lateral sclerosis. This neuroprotection against oxidation conditions suggest that these metabolites could be interesting lead candidates in drug development for neurodegenerative diseases.

  7. Ganoderma lucidum Protects Dopaminergic Neuron Degeneration through Inhibition of Microglial Activation

    Directory of Open Access Journals (Sweden)

    Ruiping Zhang

    2011-01-01

    Full Text Available Abundant evidence has suggested that neuroinflammation participates in the pathogenesis of Parkinson's disease (PD. The emerging evidence has supported that microglia may play key roles in the progressive neurodegeneration in PD and might be a promising therapeutic target. Ganoderma lucidum (GL, a traditional Chinese medicinal herb, has been shown potential neuroprotective effects in our clinical trials that make us to speculate that it might possess potent anti-inflammatory and immunomodulating properties. To test this hypothesis, we investigated the potential neuroprotective effect of GL and possible underlying mechanism of action through protecting microglial activation using co-cultures of dopaminergic neurons and microglia. The microglia is activated by LPS and MPP+-treated MES 23.5 cell membranes. Meanwhile, GL extracts significantly prevent the production of microglia-derived proinflammatory and cytotoxic factors [nitric oxide, tumor necrosis factor-α (TNF-α, interlukin 1β (IL-1β] in a dose-dependent manner and down-regulate the TNF-α and IL-1β expressions on mRNA level as well. In conclusion, our results support that GL may be a promising agent for the treatment of PD through anti-inflammation.

  8. Curcumin Protects Neurons from Glutamate-Induced Excitotoxicity by Membrane Anchored AKAP79-PKA Interaction Network

    Directory of Open Access Journals (Sweden)

    Kui Chen

    2015-01-01

    Full Text Available Now stimulation of AMPA receptor as well as its downstream pathways is considered as potential central mediators in antidepressant mechanisms. As a signal integrator which binds to AMPA receptor, A-kinase anchoring protein 79-(AKAP79- PKA complex is regarded as a potential drug target to exert neuroprotective effects. A well-tolerated and multitarget drug curcumin has been confirmed to exert antidepressant-like effects. To explore whether AKAP79-PKA complex is involved in curcumin-mediated antiexcitotoxicity, we detected calcium signaling, subcellular location of AKAP79-PKA complex, phosphorylation of glutamate receptor, and ERK and AKT cascades. In this study, we found that curcumin protected neurons from glutamate insult by reducing Ca2+ influx and blocking the translocation of AKAP79 from cytomembrane to cytoplasm. In parallel, curcumin enhanced the phosphorylation of AMPA receptor and its downstream pathways in PKA-dependent manner. If we pretreated cells with PKA anchoring inhibitor Ht31 to disassociate PKA from AKAP79, no neuroprotective effects were observed. In conclusion, our results show that AKAP79-anchored PKA facilitated the signal relay from AMPA receptor to AKT and ERK cascades, which may be crucial for curcumin-mediated antiexcitotoxicity.

  9. THE PROTECTIVE EFFECTS OF THE TOTAL SAPONIN OF DIPSACUS ASPEROIDES ON THE APOPTOSIS OF HIPPOCAMPAL NEURONS INDUCED BY β-AMYLOID PROTEIN

    Institute of Scientific and Technical Information of China (English)

    钱亦华; 杨杰; 胡海涛; 刘勇; 杨广德; 曹云新; 任惠民

    2004-01-01

    Objective To investigate the effects of the total saponin of Dipsacus asperoides (tSDA) and ginsenoside Rb1 (GRb1) on the apoptosis of primary cultured hippocampal neurons induced by β-amyloid protein (Aβ). Methods Primary cultured hippocampal neurons, the cultures were pretreated with tSDA and GRb1 on 10d for 24 hours respectively. Then the cultures were treated with 35μmol·L-1 Aβ25-35 for 24 hours, observed the changing of survival rate of neurons and the apoptosis of neurons with biochemical analysis combining immunofluorescent cytochemical double-staining technique. Results Hippocampal neurons were treated with 35μmol*L-1 Aβ for 24 hours, and survival rate of neurons downed to 52.6%. When neurons were pretreated by tSDA and GRb1, survival rate of neurons increased 11% to 15%. The findings of immunofluorescent cytochemical double-staining indicated that apoptotic neurons were obviously more than that of the blank group, reaching 43.9%.When neurons were pretreated by tSDA and GRb1, apoptotic neurons were downed to 16.6%, 10.8% respectively. Conclusion tSDA had the same effects as GRb1, protecting the neurons, antagonizing neurotoxicity of Aβ, increasing survival rate of neurons, and reducing apoptotic neurons induced by Aβ.

  10. Protective effects of Purendan superfine powder on retinal neuron apoptosis in a rat model of type 2 diabetes mellitus

    Institute of Scientific and Technical Information of China (English)

    Zhijun Dong; Xiangyi Tao; Xiaoxiao Fu; Haibin Wang; Donghua Wang; Tiemin Zhang

    2012-01-01

    This study sought to investigate the effects of Purendan superfine powder comprised of Momordica charantia, Radix Ginseng, and Radix Salviae Miltiorrhiae on neuronal apoptosis and expression of bcl-2, bax, and caspase-3, which are retinal apoptosis-associated factors in rats with diabetes mellitus induced by continuous intraperitoneal injection of streptozotocin. The results showed that Purendan superfine powder could upregulate the expression of bcl-2 protein and mRNA, and downregulate the expression of bax and caspase-3 in the retina of diabetes mellitus rats. In addition, Purendan superfine powder was shown to reduce the number of apoptotic neurons. Our experimental findings indicate that Purendan superfine powder can inhibit neuronal apoptosis in the retina of diabetes mellitus rats and has protective effects on diabetic retinopathy.

  11. Triptolide, a Chinese herbal extract, protects dopaminergic neurons from inflammation-mediated damage through inhibition of microglial activation.

    Science.gov (United States)

    Li, Feng-Qiao; Lu, Xiu-Zhi; Liang, Xi-Bin; Zhou, Hui-Fang; Xue, Bing; Liu, Xian-Yu; Niu, Dong-Bin; Han, Ji-Sheng; Wang, Xiao-Min

    2004-03-01

    Mounting lines of evidence have suggested that brain inflammation participates in the pathogenesis of Parkinson's disease. Triptolide is one of the major active components of Chinese herb Tripterygium wilfordii Hook F, which possesses potent anti-inflammatory and immunosuppressive properties. We found that triptolide concentration-dependently attenuated the lipopolysaccharide (LPS)-induced decrease in [3H]dopamine uptake and loss of tyrosine hydroxylase-immunoreactive neurons in primary mesencephalic neuron/glia mixed culture. Triptolide also blocked LPS-induced activation of microglia and excessive production of TNFalpha and NO. Our data suggests that triptolide may protect dopaminergic neurons from LPS-induced injury and its efficiency in inhibiting microglia activation may underlie the mechanism.

  12. The effect of deafness duration on neurotrophin gene therapy for spiral ganglion neuron protection.

    Science.gov (United States)

    Wise, Andrew K; Tu, Tian; Atkinson, Patrick J; Flynn, Brianna O; Sgro, Beatrice E; Hume, Cliff; O'Leary, Stephen J; Shepherd, Robert K; Richardson, Rachael T

    2011-08-01

    A cochlear implant can restore hearing function by electrically exciting spiral ganglion neurons (SGNs) in the deaf cochlea. However, following deafness SGNs undergo progressive degeneration ultimately leading to their death. One significant cause of SGN degeneration is the loss of neurotrophic support that is normally provided by cells within the organ of Corti (OC). The administration of exogenous neurotrophins (NTs) can protect SGNs from degeneration but the effects are short-lived once the source of NTs has been exhausted. NT gene therapy, whereby cells within the cochlea are transfected with genes enabling them to produce NTs, is one strategy for providing a cellular source of NTs that may provide long-term support for SGNs. As the SGNs normally innervate sensory cells within the OC, targeting residual OC cells for gene therapy in the deaf cochlea may provide a source of NTs for SGN protection and targeted regrowth of their peripheral fibers. However, the continual degeneration of the OC over extended periods of deafness may deplete the cellular targets for NT gene therapy and hence limit the effectiveness of this method in preventing SGN loss. This study examined the effects of deafness duration on the efficacy of NT gene therapy in preventing SGN loss in guinea pigs that were systemically deafened with aminoglycosides. Adenoviral vectors containing green fluorescent protein (GFP) with or without genes for Brain Derived Neurotrophic Factor (BDNF) and Neurotrophin-3 (NT3) were injected into the scala media (SM) compartment of cochleae that had been deafened for one, four or eight weeks prior to the viral injection. The results showed that viral transfection of cells within the SM was still possible even after severe degeneration of the OC. Supporting cells (pillar and Deiters' cells), cells within the stria vascularis, the spiral ligament, endosteal cells lining the scala compartments and interdental cells in the spiral limbus were transfected. However, the

  13. Tyrosol exerts a protective effect against dopaminergic neuronal cell death in in vitro model of Parkinson's disease.

    Science.gov (United States)

    Dewapriya, Pradeep; Himaya, S W A; Li, Yong-Xin; Kim, Se-Kwon

    2013-11-15

    Experimental evidence suggests that tyrosol [2-(4-hydroxyphenyl)ethanol] exhibits potent protective activities against several pathogeneses. In this study, we evaluated the protective effect of tyrosol against 1-methyl-4-phenylpyridinium (MPP(+))-induced CATH.a neuron cell death. Tyrosol dose-dependently protected CATH.a cells from MPP(+)-induced cell death and the protection was more apparent after prolong incubation (48h). The data showed that tyrosol treatment suppressed the reduction of phospho-tyrosine hydroxylase level in CATH.a cells. Further, the compound repressed MPP(+)-induced depletion of mitochondrial membrane potential (Δψm) and thereby maintained intracellular ATP production in the cell. The cellular signalling pathway studies revealed that tyrosol protected CATH.a cells from MPP(+)-induced apoptotic signalling, most likely via activation of PI3K/Akt signalling pathway along with up-regulation of anti-oxidative enzymes (SOD-1 and SOD-2) and DJ-1 protein in the cell. Collectively, present study demonstrates that tyrosol significantly protects dopaminergic neurons from MPP(+)-induced degradation, and reveals potential neuroprotective mechanism of tyrosol.

  14. Protective effects of Ginkgo biloba extract 761 against glutamate-induced neurotoxicity in cultured retinal neuron

    Institute of Scientific and Technical Information of China (English)

    WANG Yun-song; XU Liang; MA Ke; WANG Shuang; WANG Jin-jin

    2005-01-01

    @@ A large part of neuronal death is the result of episodes of anoxia and ischaemia in the retina and other eye diseases, such as anterior ischemic optic neuropathy, glaucoma. The neuronal death is due to the accumulation of glutamate in the extracellular space. Glutamate is the primary excitatory neurotransmitter in the retina. However, excessive overactivation of glutamate receptors leads to excitotoxic neuronal cell death. Glutamate induces cell death by increasing the levels of intracellular Ca2+ in neurons, thereby leading to generation of free radicals and activation proteases, as well as transcriptional activation of specific cell death programs. Glutamate excitoxicity can also cause neuronal mitochondrial membrane potential (MMP) loss, which is associated with changes in mitochondrial function leading to a neuronal dysfunction.

  15. Protective effects of antioxidants and anti-inflammatory agents against manganese-induced oxidative damage and neuronal injury

    Energy Technology Data Exchange (ETDEWEB)

    Milatovic, Dejan, E-mail: dejan.milatovic@vanderbilt.edu [Vanderbilt University School of Medicine, Department of Pediatrics, Nashville, TN (United States); Gupta, Ramesh C. [Murray State University, Breathitt Veterinary Center, Hopkinsville, KY (United States); Yu, Yingchun; Zaja-Milatovic, Snjezana [Vanderbilt University School of Medicine, Department of Pediatrics, Nashville, TN (United States); Aschner, Michael [Vanderbilt University School of Medicine, Department of Pediatrics, Nashville, TN (United States); Pharmacology and the Kennedy Center for Research on Human Development, Nashville, TN (United States)

    2011-11-15

    Exposure to excessive manganese (Mn) levels leads to neurotoxicity, referred to as manganism, which resembles Parkinson's disease (PD). Manganism is caused by neuronal injury in both cortical and subcortical regions, particularly in the basal ganglia. The basis for the selective neurotoxicity of Mn is not yet fully understood. However, several studies suggest that oxidative damage and inflammatory processes play prominent roles in the degeneration of dopamine-containing neurons. In the present study, we assessed the effects of Mn on reactive oxygen species (ROS) formation, changes in high-energy phosphates and associated neuronal dysfunctions both in vitro and in vivo. Results from our in vitro study showed a significant (p < 0.01) increase in biomarkers of oxidative damage, F{sub 2}-isoprostanes (F{sub 2}-IsoPs), as well as the depletion of ATP in primary rat cortical neurons following exposure to Mn (500 {mu}M) for 2 h. These effects were protected when neurons were pretreated for 30 min with 100 of an antioxidant, the hydrophilic vitamin E analog, trolox (6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid), or an anti-inflammatory agent, indomethacin. Results from our in vivo study confirmed a significant increase in F{sub 2}-IsoPs levels in conjunction with the progressive spine degeneration and dendritic damage of the striatal medium spiny neurons (MSNs) of mice exposed to Mn (100 mg/kg, s.c.) 24 h. Additionally, pretreatment with vitamin E (100 mg/kg, i.p.) or ibuprofen (140 {mu}g/ml in the drinking water for two weeks) attenuated the Mn-induced increase in cerebral F{sub 2}-IsoPs? and protected the MSNs from dendritic atrophy and dendritic spine loss. Our findings suggest that the mediation of oxidative stress/mitochondrial dysfunction and the control of alterations in biomarkers of oxidative injury, neuroinflammation and synaptodendritic degeneration may provide an effective, multi-pronged therapeutic strategy for protecting dysfunctional

  16. Insulin/PI3K signaling protects dentate neurons from oxygen-glucose deprivation in organotypic slice cultures.

    Science.gov (United States)

    Sun, Xiaolu; Yao, Hang; Douglas, Robert M; Gu, Xiang Q; Wang, Juan; Haddad, Gabriel G

    2010-01-01

    It is known that ischemia/reperfusion induces neurodegeneration in the hippocampus in a subregion-dependent manner. This study investigated the mechanism of selective resistance/vulnerability to oxygen-glucose deprivation (OGD) using mouse organotypic hippocampal cultures. Analysis of propidium iodide uptake showed that OGD-induced duration- and subregion-dependent neuronal injury. When compared with the CA1-3 subregions, dentate neuronal survival was more sensitive to inhibition of phosphatidylinositol 3-kinase (PI3K)/Akt signaling under basal conditions. Dentate neuronal sensitivity to PI3K/Akt signaling activation was inversely related to its vulnerability to OGD-induced injury; insulin/insulin-like growth factor 1 pre-treatment conferred neuroprotection to dentate neurons via activation of PI3K/Akt signaling. In contrast, CA1 and CA3 neurons were less sensitive to disruptions of endogenous PI3K/Akt signaling and protective effects of insulin/insulin-like growth factor 1, but more vulnerable to OGD. OGD-induced injury in CA1 was reduced by inhibition of NMDA receptor or mitogen-activated protein kinase signaling, and was prevented by blocking NMDA receptor in the presence of insulin. The CA2 subregion was distinctive in its response to glutamate, OGD, and insulin, compared with other CA subregions. CA2 neurons were sensitive to the protective effects of insulin against OGD-induced injury, but more resistant to glutamate. Distinctive distribution of insulin receptor beta and basal phospho-Akt was detected in our slice cultures. Our results suggest a role for insulin signaling in subregional resistance/vulnerability to cerebral ischemia.

  17. Coconut oil protects cortical neurons from amyloid beta toxicity by enhancing signaling of cell survival pathways.

    Science.gov (United States)

    Nafar, F; Clarke, J P; Mearow, K M

    2017-01-23

    Alzheimer's disease is a progressive neurodegenerative disease that has links with other conditions that can often be modified by dietary and life-style interventions. In particular, coconut oil has received attention as having potentially having benefits in lessening the cognitive deficits associated with Alzheimer's disease. In a recent report, we showed that neuron survival in cultures co-treated with coconut oil and Aβ was rescued compared to cultures exposed only to Aβ. Here we investigated treatment with Aβ for 1, 6 or 24 h followed by addition of coconut oil for a further 24 h, or treatment with coconut oil for 24 h followed by Aβ exposure for various periods. Neuronal survival and several cellular parameters (cleaved caspase 3, synaptophysin labeling and ROS) were assessed. In addition, the influence of these treatments on relevant signaling pathways was investigated with Western blotting. In terms of the treatment timing, our data indicated that coconut oil rescues cells pre-exposed to Aβ for 1 or 6 h, but is less effective when the pre-exposure has been 24 h. However, pretreatment with coconut oil prior to Aβ exposure showed the best outcomes. Treatment with octanoic or lauric acid also provided protection against Aβ, but was not as effective as the complete oil. The coconut oil treatment reduced the number of cells with cleaved caspase and ROS labeling, as well as rescuing the loss of synaptophysin labeling observed with Aβ treatment. Treatment with coconut oil, as well as octanoic, decanoic and lauric acids, resulted in a modest increase in ketone bodies compared to controls. The biochemical data suggest that Akt and ERK activation may contribute to the survival promoting influence of coconut oil. This was supported by observations that a PI3-Kinase inhibitor blocked the rescue effect of CoOil on Aβ amyloid toxicity. Further studies into the mechanisms of action of coconut oil and its constituent medium chain fatty acids are warranted.

  18. Magnolol protects neurons against ischemia injury via the downregulation of p38/MAPK, CHOP and nitrotyrosine

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Jiann-Hwa [Institute of Traditional Medicine, School of Medicine, National Yang-Ming University, Taipei, Taiwan (China); School of Medicine, Fu-Jen Catholic University, Taipei, Taiwan (China); Department of Emergency Medicine, Cathay General Hospital, Taipei, Taiwan (China); Kuo, Hsing-Chun [Institute of Nursing and Department of Nursing, Chang Gung University of Science and Technology, Taiwan (China); Chronic Diseases and Health Promotion Research Center, CGUST, Taiwan (China); Research Center for Industry of Human Ecology, Chang Gung University of Science and Technology, Taoyuan, Taiwan (China); Lee, Kam-Fai [Department of Pathology, Chang Gung Memorial Hospital at Chiayi, Taiwan (China); Tsai, Tung-Hu, E-mail: thtsai@ym.edu.tw [Institute of Traditional Medicine, School of Medicine, National Yang-Ming University, Taipei, Taiwan (China); Graduate Institute of Acupuncture Science, China Medical University, Taichung, Taiwan (China); Department of Education and Research, Taipei City Hospital, Taipei, Taiwan (China)

    2014-09-15

    Magnolol is isolated from the herb Magnolia officinalis, which has been demonstrated to exert pharmacological effects. Our aim was to investigate whether magnolol is able to act as an anti-inflammatory agent that brings about neuroprotection using a global ischemic stroke model and to determine the mechanisms involved. Rats were treated with and without magnolol after ischemia reperfusion brain injury by occlusion of the two common carotid arteries. The inflammatory cytokine production in serum and the volume of infarction in the brain were measured. The proteins present in the brains obtained from the stroke animal model (SAM) and control animal groups with and without magnolol treatment were compared. Magnolol reduces the total infarcted volume by 15% and 30% at dosages of 10 and 30 mg/kg, respectively, compared to the untreated SAM group. The levels of acute inflammatory cytokines, including interleukin-1 beta, tumor necrosis factor alpha, and interleukin-6 were attenuated by magnolol. Magnolol was also able to suppress the production of nitrotyrosine, 4-hydroxy-2-nonenal (4-HNE), inducible NO synthase (iNOS), various phosphorylated p38 mitogen-activated protein kinases and various C/EBP homologues. Furthermore, this modulation of ischemia injury factors in the SAM model group treated with magnolol seems to result from a suppression of reactive oxygen species production and the upregulation of p-Akt and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB). These findings confirm the anti-oxidative properties of magnolol, including the inhibition of ischemic injury to neurons; this protective effect seems to involve changes in the in vivo activity of Akt, GSK3β and NF-κB. - Graphical abstract: Schematic presentation of the signaling pathways involved in magnolol inhibited transient global ischemia brain apoptosis and inflammation in rats. The effect of magnolol on the scavenger of ROS, which inhibits p38 MAPK and CHOP protein inactivation

  19. Melatonin Mediates Protective Effects against Kainic Acid-Induced Neuronal Death through Safeguarding ER Stress and Mitochondrial Disturbance

    Science.gov (United States)

    Xue, Feixiao; Shi, Cai; Chen, Qingjie; Hang, Weijian; Xia, Liangtao; Wu, Yue; Tao, Sophia Z.; Zhou, Jie; Shi, Anbing; Chen, Juan

    2017-01-01

    Kainic acid (KA)-induced neuronal death is linked to mitochondrial dysfunction and ER stress. Melatonin is known to protect hippocampal neurons from KA-induced apoptosis, but the exact mechanisms underlying melatonin protective effects against neuronal mitochondria disorder and ER stress remain uncertain. In this study, we investigated the sheltering roles of melatonin during KA-induced apoptosis by focusing on mitochondrial dysfunction and ER stress mediated signal pathways. KA causes mitochondrial dynamic disorder and dysfunction through calpain activation, leading to neuronal apoptosis. Ca2+ chelator BAPTA-AM and calpain inhibitor calpeptin can significantly restore mitochondrial morphology and function. ER stress can also be induced by KA treatment. ER stress inhibitor 4-phenylbutyric acid (PBA) attenuates ER stress-mediated apoptosis and mitochondrial disorder. It is worth noting that calpain activation was also inhibited under PBA administration. Thus, we concluded that melatonin effectively inhibits KA-induced calpain upregulation/activation and mitochondrial deterioration by alleviating Ca2+ overload and ER stress. PMID:28293167

  20. Metformin Protects Neurons against Oxygen-Glucose Deprivation/Reoxygenation -Induced Injury by Down-Regulating MAD2B

    Directory of Open Access Journals (Sweden)

    Xianfang Meng

    2016-11-01

    Full Text Available Background/Aims: Metformin, the common medication for type II diabetes, has protective effects on cerebral ischemia. However, the molecular mechanisms are far from clear. Mitotic arrest deficient 2-like protein 2 (MAD2B, an inhibitor of the anaphase-promoting complex (APC, is widely expressed in hippocampal and cortical neurons and plays an important role in mediating high glucose-induced neurotoxicity. The present study investigated whether metformin modifies the expression of MAD2B and to exert its neuroprotective effects in primary cultured cortical neurons during oxygen-glucose deprivation/reoxygenation (OGD/R, a widely used in vitro model of ischemia/reperfusion. Methods: Primary cortical neurons were cultured, deprived of oxygen-glucose for 1 h, and then recovered with oxygen-glucose for 12 h and 24 h. Cell viability was measured by detecting the levels of lactate dehydrogenase (LDH in culture medium. The levels of MAD2B, cyclin B and p-histone 3 were measured by Western blot. Results: Cell viability of neurons was reduced under oxygen-glucose deprivation/reoxygenation (OGD/R. The expression of MAD2B was increased under OGD/R. The levels of cyclin B1, which is a substrate of APC, were also increased. Moreover, OGD/R up-regulated the phosphorylation levels of histone 3, which is the induction of aberrant re-entry of post-mitotic neurons. However, pretreatment of neurons with metformin alleviated OGD/R-induced injury. Metformin further decreased the expression of MAD2B, cyclin B1 and phosphorylation levels of histone 3. Conclusion: Metformin exerts its neuroprotective effect through regulating the expression of MAD2B in neurons under OGD/R.

  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. Inhibition of Histone Deacetylase 3 (HDAC3) Mediates Ischemic Preconditioning and Protects Cortical Neurons against Ischemia in Rats

    Science.gov (United States)

    Wu, Qimei; Zhang, Lei; Feng, Linyin

    2016-01-01

    Brain ischemic preconditioning (PC) provides vital insights into the endogenous protection against stroke. Genomic and epigenetic responses to PC condition the brain into a state of ischemic tolerance. Notably, PC induces the elevation of histone acetylation, consistent with evidence that histone deacetylase (HDAC) inhibitors protect the brain from ischemic injury. However, less is known about the specific roles of HDACs in this process. HDAC3 has been implicated in several neurodegenerative conditions. Deletion of HDAC3 confers protection against neurotoxicity and neuronal injury. Here, we hypothesized that inhibition of HDAC3 may contribute to the neuronal survival elicited by PC. To address this notion, PC and transient middle cerebral artery occlusion (MCAO) were conducted in Sprague-Dawley rats. Additionally, primary cultured cortical neurons were used to identify the modulators and effectors of HDAC3 involved in PC. We found that nuclear localization of HDAC3 was significantly reduced following PC in vivo and in vitro. Treatment with the HDAC3-specific inhibitor, RGFP966, mimicked the neuroprotective effects of PC 24 h and 7 days after MCAO, causing a reduced infarct volume and less Fluoro-Jade C staining. Improved functional outcomes were observed in the neurological score and rotarod test. We further showed that attenuated recruitment of HDAC3 to promoter regions following PC potentiates transcriptional initiation of genes including Hspa1a, Bcl2l1, and Prdx2, which may underlie the mechanism of protection. In addition, PC-activated calpains were implicated in the cleavage of HDAC3. Pretreatment with calpeptin blockaded the attenuated nuclear distribution of HDAC3 and the protective effect of PC in vivo. Collectively, these results demonstrate that the inhibition of HDAC3 preconditions the brain against ischemic insults, indicating a new approach to evoke endogenous protection against stroke. PMID:27965534

  3. Inhibition of Histone Deacetylase 3 (HDAC3 Mediates Ischemic Preconditioning and Protects Cortical Neurons against Ischemia in Rats

    Directory of Open Access Journals (Sweden)

    Xiaoyu Yang

    2016-11-01

    Full Text Available Brain ischemic preconditioning (PC provides vital insights into the endogenous protection against stroke. Genomic and epigenetic responses to PC condition the brain into a state of ischemic tolerance. Notably, PC induces the elevation of histone acetylation, consistent with evidence that histone deacetylase (HDAC inhibitors protect the brain from ischemic injury. However, less is known about the specific roles of HDACs in this process. HDAC3 has been implicated in several neurodegenerative conditions. Deletion of HDAC3 confers protection against neurotoxicity and neuronal injury. Here, we hypothesized that inhibition of HDAC3 may contribute to the neuronal survival elicited by PC. To address this notion, PC and transient middle cerebral artery occlusion (MCAO were conducted in Sprague-Dawley rats. Additionally, primary cultured cortical neurons were used to identify the modulators and effectors of HDAC3 involved in PC. We found that nuclear localization of HDAC3 was significantly reduced following PC in vivo and in vitro. Treatment with the HDAC3-specific inhibitor, RGFP966, mimicked the neuroprotective effects of PC 24 h and 7 d after MCAO, causing a reduced infarct volume and less Fluoro-Jade C staining. Improved functional outcomes were observed in the neurological score and rotarod test. We further showed that attenuated recruitment of HDAC3 to promoter regions following PC potentiates transcriptional initiation of genes including Hspa1a, Bcl2l1, and Prdx2, which may underlie the mechanism of protection. In addition, PC-activated calpains were implicated in the cleavage of HDAC3. Pretreatment with calpeptin blockaded the attenuated nuclear distribution of HDAC3 and the protective effect of PC in vivo. Collectively, these results demonstrate that the inhibition of HDAC3 preconditions the brain against ischemic insults, indicating a new approach to evoke endogenous protection against stroke.

  4. Protective role of melatonin in domoic acid-induced neuronal damage in the hippocampus of adult rats.

    Science.gov (United States)

    Ananth, C; Gopalakrishnakone, P; Kaur, C

    2003-01-01

    Domoic acid (DA), a kainite-receptor agonist and potent inducer of neurotoxicity, has been administered intravenously in adult rats in the present study (0.75 mg/kg body weight) to demonstrate neuronal degeneration followed by glial activation and their involvement with inducible nitric oxide synthase (iNOS) in the hippocampus. An equal volume of normal saline was administered in control rats. The pineal hormone melatonin, which protects the neurons efficiently against excitotoxicity mediated by sensitive glutamate receptor, was administered intraperitoneally (10 mg/kg body weight), 20 min before, immediately after, and 1 h and 2 h after the DA administration, to demonstrate its role in therapeutic strategy. Histopathological analysis (Nissl staining) demonstrated extensive neuronal damage in the pyramidal neurons of CA1, CA3 subfields and hilus of the dentate gyrus (DG) in the hippocampus at 5 days after DA administration. Sparsely distributed glial fibrillary acidic protein (GFAP)-immunoreactive astrocytes were observed in the hippocampus at 4-24 h after DA administration and in the control rats. Astrogliosis was evidenced by increased GFAP immunoreactivity in the areas of severe neuronal degeneration at 5 days after DA administration. Along with this, microglial cells exhibited an intense immunoreaction with OX-42, indicating upregulation of complement type 3 receptors (CR3). Ultrastructural study revealed swollen or shrunken degenerating neurons in the CA1, CA3 subfields and hilus of the DG and hypertrophied astrocytes showing accumulation of intermediate filament bundles in the cytoplasm were observed after administration of DA. Although no significant change could be observed in the mRNA level of iNOS expression between the DA-treated rats and controls at 4-24 h and at 5-day time intervals, double immunofluorescense revealed co-expression of induced iNOS with GFAP immunoreactive astrocytes, but not in the microglial cells, and iNOS expression in the neurons

  5. Chlorogenic acid protection of neuronal nitric oxide synthase-positive neurons in the hippocampus of mice with impaired learning and memory

    Institute of Scientific and Technical Information of China (English)

    Qiuyun Tu; Xiangqi Tang; Zhiping Hu

    2008-01-01

    of correct responses in the Y-maze test was greater in the ehlorogenic acid-treated group than in the model group. CONCLUSION: Chlorogenic acid protects kainic acid-induced injury to nNOS-positive neurons in the hippocampal CA1-4 regions, thereby ameliorating learning and memory impairment.

  6. Interleukin-4 Protects Dopaminergic Neurons In vitro but Is Dispensable for MPTP-Induced Neurodegeneration In vivo

    Science.gov (United States)

    Hühner, Laura; Rilka, Jennifer; Gilsbach, Ralf; Zhou, Xiaolai; Machado, Venissa; Spittau, Björn

    2017-01-01

    Microglia are involved in physiological as well as neuropathological processes in the central nervous system (CNS). Their functional states are often referred to as M1-like and M2-like activation, and are believed to contribute to neuroinflammation-mediated neurodegeneration or neuroprotection, respectively. Parkinson’s disease (PD) is one the most common neurodegenerative disease and is characterized by the progressive loss of midbrain dopaminergic (mDA) neurons in the substantia nigra resulting in bradykinesia, tremor, and rigidity. Interleukin 4 (IL4)-mediated M2-like activation of microglia, which is characterized by upregulation of alternative markers Arginase 1 (Arg1) and Chitinase 3 like 3 (Ym1) has been well studied in vitro but the role of endogenous IL4 during CNS pathologies in vivo is not well understood. Interestingly, microglia activation by IL4 has been described to promote neuroprotective and neurorestorative effects, which might be important to slow the progression of neurodegenerative diseases. In the present study, we addressed the role of endogenous and exogenous IL4 during MPP+-induced degeneration of mDA neurons in vitro and further addressed the impact of IL4-deficiency on neurodegeneration in the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) mouse model of PD in vivo. Our results clearly demonstrate that exogenous IL4 is important to protect mDA neurons in vitro, but endogenous IL4 seems to be dispensable for development and maintenance of the nigrostriatal system as well as MPTP-induced loss of TH+ neurons in vivo. These results underline the importance of IL4 in promoting a neuroprotective microglia activation state and strengthen the therapeutic potential of exogenous IL4 for protection of mDA neurons in PD models. PMID:28337124

  7. 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.

  8. Sulforaphane protects primary cultures of cortical neurons against injury induced by oxygen-glucose deprivation/reoxygenation via antiapoptosis

    Institute of Scientific and Technical Information of China (English)

    Xuemei Wu; Jing Zhao; Shanshan Yu; Yanlin Chen; Jingxian Wu; Yong Zhao

    2012-01-01

    Objective To determine whether sulforaphane (SFN) protects neurons against injury caused by oxygenglucose deprivation/reoxygenation (OGD/R) and,if so,to investigate the possible mechanisms.Methods Primary cultures of neurons were prepared from the cerebral cortex of 1-day-old Sprague-Dawley rats.On days 5-6 in vitro,the neurons were exposed to OGD for 1 h,followed by reoxygenation for 24 h.Cells were treated with 0,0.1,0.2,0.5,1,2.5,or 5 μmol/L SFN,with or without 10 μmol/L LY294002,a PI3K-specific inhibitor,during OGD/R (a total of 25 h).After 24-h reoxygenation,MTT was used to assess viability and injury was assessed by Hoechst 33258/propidium iodide (PI) staining;immunofluorescence staining and Western blot were performed to detect molecular events associated with apoptosis.Results The MTT assay showed that 1 μmol/L SFN significantly increased viability,and Hoechst 33258/PI staining showed that the numbers of injured neurons were reduced significantly in the SFN group.Furthermore,immunofluorescence staining and Westem blot showed that SFN increased Bcl-2 and decreased cleaved caspase-3 levels.Moreover,LY294002 inhibited the phosphorylated-Akt expression evoked by SFN,decreased Bcl-2 expression and increased cleaved caspase-3 expression.Conclusion SFN protects neurons against injury from OGD/R and this effect may be partly associated with an antiapoptosis pathway.

  9. Activation of Transcription Factor MEF2D by Bis(3)-cognitin Protects Dopaminergic Neurons and Ameliorates Parkinsonian Motor Defects*

    Science.gov (United States)

    Yao, Lu; Li, Wenming; She, Hua; Dou, Juan; Jia, Leili; He, Yingli; Yang, Qian; Zhu, Jinqiu; Cápiro, Natalie L.; Walker, Douglas I.; Pennell, Kurt D.; Pang, Yuanping; Liu, Yong; Han, Yifan; Mao, Zixu

    2012-01-01

    Parkinson disease (PD) is characterized by the selective demise of dopaminergic (DA) neurons in the substantial nigra pars compacta. Dysregulation of transcriptional factor myocyte enhancer factor 2D (MEF2D) has been implicated in the pathogenic process in in vivo and in vitro models of PD. Here, we identified a small molecule bis(3)-cognitin (B3C) as a potent activator of MEF2D. We showed that B3C attenuated the toxic effects of neurotoxin 1-methyl-4-phenylpyridinium (MPP+) by activating MEF2D via multiple mechanisms. B3C significantly reduced MPP+-induced oxidative stress and potentiated Akt to down-regulate the activity of MEF2 inhibitor glycogen synthase kinase 3β (GSK3β) in a DA neuronal cell line SN4741. Furthermore, B3C effectively rescued MEF2D from MPP+-induced decline in both nucleic and mitochondrial compartments. B3C offered SN4741 cells potent protection against MPP+-induced apoptosis via MEF2D. Interestingly, B3C also protected SN4741 cells from wild type or mutant A53T α-synuclein-induced cytotoxicity. Using the in vivo PD model of C57BL/6 mice treated with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine hydrochloride (MPTP), we showed that B3C maintained redox homeostasis, promoted Akt function activity, and restored MEF2D level in midbrain neurons. Moreover, B3C greatly prevented the loss of tyrosine hydroxylase signal in substantial nigra pars compacta DA neurons and ameliorated behavioral impairments in mice treated with MPTP. Collectedly, our studies identified B3C as a potent neuroprotective agent whose effectiveness relies on its ability to effectively up-regulate MEF2D in DA neurons against toxic stress in models of PD in vitro and in vivo. PMID:22891246

  10. Activation of transcription factor MEF2D by bis(3)-cognitin protects dopaminergic neurons and ameliorates Parkinsonian motor defects.

    Science.gov (United States)

    Yao, Lu; Li, Wenming; She, Hua; Dou, Juan; Jia, Leili; He, Yingli; Yang, Qian; Zhu, Jinqiu; Cápiro, Natalie L; Walker, Douglas I; Pennell, Kurt D; Pang, Yuanping; Liu, Yong; Han, Yifan; Mao, Zixu

    2012-10-05

    Parkinson disease (PD) is characterized by the selective demise of dopaminergic (DA) neurons in the substantial nigra pars compacta. Dysregulation of transcriptional factor myocyte enhancer factor 2D (MEF2D) has been implicated in the pathogenic process in in vivo and in vitro models of PD. Here, we identified a small molecule bis(3)-cognitin (B3C) as a potent activator of MEF2D. We showed that B3C attenuated the toxic effects of neurotoxin 1-methyl-4-phenylpyridinium (MPP(+)) by activating MEF2D via multiple mechanisms. B3C significantly reduced MPP(+)-induced oxidative stress and potentiated Akt to down-regulate the activity of MEF2 inhibitor glycogen synthase kinase 3β (GSK3β) in a DA neuronal cell line SN4741. Furthermore, B3C effectively rescued MEF2D from MPP(+)-induced decline in both nucleic and mitochondrial compartments. B3C offered SN4741 cells potent protection against MPP(+)-induced apoptosis via MEF2D. Interestingly, B3C also protected SN4741 cells from wild type or mutant A53T α-synuclein-induced cytotoxicity. Using the in vivo PD model of C57BL/6 mice treated with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine hydrochloride (MPTP), we showed that B3C maintained redox homeostasis, promoted Akt function activity, and restored MEF2D level in midbrain neurons. Moreover, B3C greatly prevented the loss of tyrosine hydroxylase signal in substantial nigra pars compacta DA neurons and ameliorated behavioral impairments in mice treated with MPTP. Collectedly, our studies identified B3C as a potent neuroprotective agent whose effectiveness relies on its ability to effectively up-regulate MEF2D in DA neurons against toxic stress in models of PD in vitro and in vivo.

  11. Cesium chloride protects cerebellar granule neurons from apoptosis induced by low potassium.

    Science.gov (United States)

    Zhong, Jin; Yao, Weiguo; Lee, Weihua

    2007-10-01

    Neuronal apoptosis plays a critical role in the pathogenesis of neurodegenerative disorders, and neuroprotective agents targeting apoptotic signaling could have therapeutic use. Here we report that cesium chloride, an alternative medicine in treating radiological poison and cancer, has neuroprotective actions. Serum and potassium deprivation induced cerebellar granule neurons to undergo apoptosis, which correlated with the activation of caspase-3. Cesium prevented both the activation of caspase-3 and neuronal apoptosis in a dose-dependent manner. Cesium at 8 mM increased the survival of neurons from 45 +/- 3% to 91 +/- 5% of control. Cesium's neuroprotection was not mediated by PI3/Akt or MAPK signaling pathways, since it was unable to activate either Akt or MAPK by phosphorylation. In addition, specific inhibitors of PI3 kinase and MAP kinase did not block cesium's neuroprotective effects. On the other hand, cesium inactivated GSK3beta by phosphorylation of serine-9 and GSK3beta-specific inhibitor SB415286 prevented neuronal apoptosis. These data indicate that cesium's neuroprotection is likely via inactivating GSK3beta. Furthermore, cesium also prevented H(2)O(2)-induced neuronal death (increased the survival of neurons from 72 +/- 4% to 89 +/- 3% of control). Given its relative safety and good penetration of the brain blood barrier, our findings support the potential therapeutic use of cesium in neurodegenerative diseases.

  12. Thiopental inhibits global protein synthesis by repression of eukaryotic elongation factor 2 and protects from hypoxic neuronal cell death.

    Directory of Open Access Journals (Sweden)

    Christian I Schwer

    Full Text Available Ischemic and traumatic brain injury is associated with increased risk for death and disability. The inhibition of penumbral tissue damage has been recognized as a target for therapeutic intervention, because cellular injury evolves progressively upon ATP-depletion and loss of ion homeostasis. In patients, thiopental is used to treat refractory intracranial hypertension by reducing intracranial pressure and cerebral metabolic demands; however, therapeutic benefits of thiopental-treatment are controversially discussed. In the present study we identified fundamental neuroprotective molecular mechanisms mediated by thiopental. Here we show that thiopental inhibits global protein synthesis, which preserves the intracellular energy metabolite content in oxygen-deprived human neuronal SK-N-SH cells or primary mouse cortical neurons and thus ameliorates hypoxic cell damage. Sensitivity to hypoxic damage was restored by pharmacologic repression of eukaryotic elongation factor 2 kinase. Translational inhibition was mediated by calcium influx, activation of the AMP-activated protein kinase, and inhibitory phosphorylation of eukaryotic elongation factor 2. Our results explain the reduction of cerebral metabolic demands during thiopental treatment. Cycloheximide also protected neurons from hypoxic cell death, indicating that translational inhibitors may generally reduce secondary brain injury. In conclusion our study demonstrates that therapeutic inhibition of global protein synthesis protects neurons from hypoxic damage by preserving energy balance in oxygen-deprived cells. Molecular evidence for thiopental-mediated neuroprotection favours a positive clinical evaluation of barbiturate treatment. The chemical structure of thiopental could represent a pharmacologically relevant scaffold for the development of new organ-protective compounds to ameliorate tissue damage when oxygen availability is limited.

  13. L-carnitine protects neurons from 1-methyl-4-phenylpyridinium-induced neuronal apoptosis in rat forebrain culture.

    Science.gov (United States)

    Wang, C; Sadovova, N; Ali, H K; Duhart, H M; Fu, X; Zou, X; Patterson, T A; Binienda, Z K; Virmani, A; Paule, M G; Slikker, W; Ali, S F

    2007-01-05

    1-Methyl-4-phenylpyridinium ion (MPP+), an inhibitor of mitochondrial complex I, has been widely used as a neurotoxin because it elicits a severe Parkinson's disease-like syndrome with an elevation of intracellular reactive oxygen species (ROS) and apoptosis. L-carnitine plays an integral role in attenuating the brain injury associated with mitochondrial neurodegenerative disorders. The present study investigates the effects of L-carnitine against the toxicity of MPP+ in rat forebrain primary cultures. Cells in culture were treated for 24 h with 100, 250, 500 and 1000 microM MPP+ alone or co-incubated with L-carnitine. MPP+ produced a dose-related increase in DNA fragmentation as measured by cell death ELISA (enzyme-linked immunosorbent assay), an increase in the number of TUNEL (terminal dUTP nick-end labeling)-positive cells and a reduction in the mitochondrial metabolism of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT). No significant effect was observed with the release of lactate dehydrogenase (LDH), indicating that cell death presumably occurred via apoptotic mechanisms. Co-incubation of MPP+ with L-carnitine significantly reduced MPP+-induced apoptosis. Western blot analyses showed that neurotoxic concentrations of MPP+ decreased the ratio of BCL-X(L) to Bax and decreased the protein levels of polysialic acid neural cell adhesion molecules (PSA-NCAM), a neuron specific marker. L-carnitine blocked these effects of MPP+ suggesting its potential therapeutic utility in degenerative disorders such as Parkinson's disease, Alzheimer's disease, ornithine transcarbamylase deficiency and other mitochondrial diseases.

  14. Protective effects of peony root extract and its components on neuron damage in the hippocampus induced by the cobalt focus epilepsy model.

    Science.gov (United States)

    Tsuda, T; Sugaya, A; Ohguchi, H; Kishida, N; Sugaya, E

    1997-08-01

    Protective effects of peony root extract and its components on neuron damage in the CA1 area of the hippocampus induced by the cobalt focus epilepsy model were examined. Neuron damage in the CA1 area of the hippocampus and frequent spike discharges induced by application of metallic cobalt to the cerebral cortex of rats were completely prevented when peony root extract was continuously administered orally at 1 g/kg/day for 30 days prior to cobalt application. Component crude gallotannin fraction showed marked but incomplete protective action. A combination of crude gallotannin fraction and paeoniflorin showed complete protective action in the same way as peony root extract against neuron damage although use of paeoniflorin alone had no effect. These findings together with our previous reports indicate that peony root extract and its component, gallotannin, have excellent protective effects on neuron damage in addition to anticonvulsant action by prior oral administration.

  15. Poloxamer-188 and citicoline provide neuronal membrane integrity and protect membrane stability in cortical spreading depression.

    Science.gov (United States)

    Yıldırım, Timur; Eylen, Alpaslan; Lule, Sevda; Erdener, Sefik Evren; Vural, Atay; Karatas, Hulya; Ozveren, Mehmet Faik; Dalkara, Turgay; Gursoy-Ozdemir, Yasemin

    2015-01-01

    Under pathological conditions such as brain trauma, subarachnoid hemorrhage and stroke, cortical spreading depression (CSD) or peri-infarct depolarizations contribute to brain damage in animal models of neurological disorders as well as in human neurological diseases. CSD causes transient megachannel opening on the neuronal membrane, which may compromise neuronal survival under pathological conditions. Poloxamer-188 (P-188) and citicoline are neuroprotectants with membrane sealing properties. The aim of this study is to investigate the effect of P-188 and citicoline on the neuronal megachannel opening induced by CSD in the mouse brain. We have monitored megachannel opening with propidium iodide, a membrane impermeable fluorescent dye and, demonstrate that P-188 and citicoline strikingly decreased CSD-induced neuronal PI influx in cortex and hippocampal dentate gyrus. Therefore, these agents may be providing neuroprotection by blocking megachannel opening, which may be related to their membrane sealing action and warrant further investigation for treatment of traumatic brain injury and ischemic stroke.

  16. Curcumin protects nigral dopaminergic neurons by iron-chelation in the 6-hydroxydopamine rat model of Parkinson's disease

    Institute of Scientific and Technical Information of China (English)

    Xi-Xun Du; Hua-Min Xu; Hong Jiang; Ning Song; Jun Wang; Jun-Xia Xie

    2012-01-01

    [Objective] Curcumin is a plant polyphenolic compound and a major component of spice turmeric (Curcuma longa).It has been reported to possess free radical-scavenging,iron-chelating,and anti-inflammatory properties in different tissues.Our previous study showed that curcumin protects MES23.5 dopaminergic cells from 6-hydroxydopamine (6-OHDA)-induced neurotoxicity in vitro.The present study aimed to explore this neuroprotective effect in the 6-OHDAlesioned rat model of Parkinson's disease in vivo.[Methods] Rats were given intragastric curcumin for 24 days.6-OHDA lesioning was conducted on day 4 of curcumin treatment.Dopamine content was assessed by high-performance liquid chromatography with electrochemical detection,tyrosine hydroxylase (TH)-containing neurons by immunohistochemistry,and iron-containing cells by Perls' iron staining.[Results] The dopamine content in the striatum and the number of THimmunoreactive neurons decreased after 6-OHDA treatment.Curcumin pretreatment reversed these changes.Further studies demonstrated that 6-OHDA treatment increased the number of iron-staining cells,which was dramatically decreased by curcumin pretreatment.[Conclusion]The protective effects of curcumin against 6-OHDA may be attributable to the ironchelating activity of curcumin to suppress the iron-induced degeneration of nigral dopaminergic neurons.

  17. The protective role of ascorbic acid on hippocampal CA1 pyramidal neurons in a rat model of maternal lead exposure.

    Science.gov (United States)

    Sepehri, Hamid; Ganji, Farzaneh

    2016-07-01

    Oxidative stress is a major pathogenic mechanism of lead neurotoxicity. The antioxidant ascorbic acid protects hippocampal pyramidal neurons against cell death during congenital lead exposure; however, critical functions like synaptic transmission, integration, and plasticity depend on preservation of dendritic and somal morphology. This study was designed to examine if ascorbic acid also protects neuronal morphology during developmental lead exposure. Timed pregnant rats were divided into four treatment groups: (1) control, (2) 100mg/kg ascorbic acid once a day via gavage, (3) 0.05% lead acetate in drinking water, and (4) 0.05% lead+100mg/kg oral ascorbic acid. Brains of eight male pups (P25) per treatment group were processed for Golgi staining. Changes in hippocampal CA1 pyramidal neurons' somal size were estimated by cross-sectional area and changes in dendritic arborization by Sholl's analysis. One-way ANOVA was used to compare results among treatment groups. Lead-exposed pups exhibited a significant decrease in somal size compared to controls (Pascorbic acid. Sholl's analysis revealed a significant increase in apical dendritic branch points near cell body (PAscorbic acid significantly but only partially reversed the somal and dendritic damage caused by developmental lead exposure. Oxidative stress thus contributes to lead neurotoxicity but other pathogenic mechanisms are also involved.

  18. Hinokitiol protects primary neuron cells against prion peptide-induced toxicity via autophagy flux regulated by hypoxia inducing factor-1.

    Science.gov (United States)

    Moon, Ji-Hong; Lee, Ju-Hee; Lee, You-Jin; Park, Sang-Youel

    2016-05-24

    Prion diseases are fatal neurodegenerative disorders that are derived from structural changes of the native PrPc. Recent studies indicated that hinokitiol induced autophagy known to major function that keeps cells alive under stressful conditions. We investigated whether hinokitiol induces autophagy and attenuates PrP (106-126)-induced neurotoxicity. We observed increase of LC3-II protein level, GFP-LC3 puncta by hinokitiol in neuronal cells. Addition to, electron microscopy showed that hinokitiol enhanced autophagic vacuoles in neuronal cells. We demonstrated that hinokitiol protects against PrP (106-126)-induced neurotoxicity via autophagy by using autophagy inhibitor, wortmannin and 3MA, and ATG5 small interfering RNA (siRNA). We checked hinokitiol activated the hypoxia-inducible factor-1α (HIF-1α) and identified that hinokitiol-induced HIF-1α regulated autophagy. Taken together, this study is the first report demonstrating that hinokitiol protected against prion protein-induced neurotoxicity via autophagy regulated by HIF-1α. We suggest that hinokitiol is a possible therapeutic strategy in neuronal disorders including prion disease.

  19. Interleukin-18 directly protects cortical neurons by activating PI3K/AKT/NF-κB/CREB pathways.

    Science.gov (United States)

    Zhou, Jia; Ping, Feng-feng; Lv, Wen-ting; Feng, Jun-yi; Shang, Jing

    2014-09-01

    Interleukin-18 (IL-18), a member of the IL-1 family of cytokines, was initially identified as an interferon (IFN)-γ-inducing factor. IL-18 is expressed in both immune and non-immune cells and participates in the adjustment of multitude cellular functions. Nonetheless, the effects of IL-18 on cortical neurons have not been explored. The present study was conducted to investigate the influence of IL-18 on rat primary cortical neurons and elucidate the underlying mechanisms. We proved that rrIL-18 increased the brain-derived neurotrophic factor (BDNF) expression in a time-dependent manner. Treatment with rrIL-18 (50 ng/ml) deactivated phosphatase and tensin homolog deleted on chromosome 10 (PTEN) by facilitating its phosphorylation, enhanced the expression of Phosphoinositide 3-OH kinase (PI3K) and p-Akt, standing for the activation of the PI3K/Akt pathway. As its pivotal downstream pathways, nuclear factor-kappa B (NF-κB), cAMP-responsive element binding protein (CREB)/Bcl-2 and glycogen synthase kinase-3β (GSK-3β) were examined in further steps. Our data revealed that rrIL-18 stimulated NF-κB activation, improved p-CREB and anti-apoptotic Bcl-2 expression levels. But rrIL-18 had little or no effect on GSK-3β pathway. Besides, rrIL-18 increased levels of BDNF and Bcl-2/Bax ratio and decreased cleaved caspase-3 expression to protect cortical neurons from damage induced by oxygen-glucose deprivation (OGD). These results in vitro showed the protection of IL-18 on cortical neurons. And this direct neuroprotective effect of IL-18 is crippled by PI3K inhibitor wortmannin.

  20. Dihydromyricetin protects neurons in an MPTP-induced model of Parkinson's disease by suppressing glycogen synthase kinase-3 beta activity

    Science.gov (United States)

    Ren, Zhao-xiang; Zhao, Ya-fei; Cao, Ting; Zhen, Xue-chu

    2016-01-01

    Aim: It is general believed that mitochondrial dysfunction and oxidative stress play critical roles in the pathology of Parkinson's disease (PD). Dihydromyricetin (DHM), a natural flavonoid extracted from Ampelopsis grossedentata, has recently been found to elicit potent anti-oxidative effects. In the present study, we explored the role of DHM in protecting dopaminergic neurons. Methods: Male C57BL/6 mice were intraperitoneally injected with 1-methyl4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) for 7 d to induce PD. Additionally, mice were treated with either 5 or 10 mg/kg DHM for a total of 13 d (3 d before the start of MPTP, during MPTP administration (7 d) and 3 d after the end of MPTP). For the saline or DHM alone treatment groups, mice were injected with saline or DHM for 13 d. On d 14, behavioral tests (locomotor activity, the rotarod test and the pole test) were administered. After the behavioral tests, the mice were sacrificed, and brain tissue was collected for immunofluorescence staining and Western blotting. In addition, MES23.5 cells were treated with MPP+ and DHM, and evaluated using cell viability assays, reactive oxygen species (ROS) measurements, apoptosis analysis and Western blotting. Results: DHM significantly attenuated MPTP-induced mouse behavioral impairments and dopaminergic neuron loss. In the MES23.5 cells, DHM attenuated MPP+-induced cell injury and ROS production in a dose-dependent manner. In addition, DHM increased glycogen synthase kinase-3 beta phosphorylation in a dose- and time-dependent manner, which may be associated with DHM-induced dopaminergic neuronal protection. Conclusion: The present study demonstrated that DHM is a potent neuroprotective agent for DA neurons by modulating the Akt/GSK-3β pathway, which suggests that DHM may be a promising therapeutic candidate for PD. PMID:27374489

  1. Trans-anethole protects cortical neuronal cells against oxygen-glucose deprivation/reoxygenation.

    Science.gov (United States)

    Ryu, Sangwoo; Seol, Geun Hee; Park, Hyeon; Choi, In-Young

    2014-10-01

    Trans-anethole has been studied on pharmacological properties such as anti-inflammation, anti-oxidative stress, antifungal and anticancer. However, to date, the anti-ischemic effects of trans-anethole have not been assessed. Therefore, we investigated the neuroprotection of trans-anethole against oxygen-glucose deprivation/reoxygenation (OGD/R)-induced cortical neuronal cell injury, an in vitro model of ischemia. The abilities of trans-anethole to block excitotoxicity, oxidative stress and mitochondrial dysfunction were evaluated in OGD/R-induced neurons. Trans-anethole significantly ameliorated OGD/R-induced neuronal cell injury by attenuating the intracellular calcium overload via the activation of NMDA receptors. Trans-anethole also inhibited OGD/R-induced reactive oxygen species overproduction, which may be derived from the scavenging activity in peroxyl radicals, assessed in an oxygen radical absorbance capacity assay. Furthermore, trans-anethole was shown to attenuate the depolarization of mitochondrial transmembrane. These results indicated that the neuroprotective effect of trans-anethole on OGD/R-induced neuronal injury might be due to its ability to inhibit excitotoxicity, oxidative stress and mitochondrial dysfunction. Considering these multiple pathways causing ischemic neuronal damage, the multi-functional effect of trans-anethole suggested that it may be effective in treating ischemic stroke.

  2. Cytisine confers neuronal protection against excitotoxic injury by down-regulating GluN2B-containing NMDA receptors.

    Science.gov (United States)

    Li, Yu-Jiao; Yang, Qi; Zhang, Kun; Guo, Yan-Yan; Li, Xu-Bo; Yang, Le; Zhao, Ming-Gao; Wu, Yu-Mei

    2013-01-01

    Cytisine (CYT), one of the principal bioactive components derived from the seeds of Cytisus laborinum L, has been widely used for central nervous system (CNS) diseases treatment. The present study investigated the protective effect of CYT on cultured cortical neural injury induced by N-methyl-d-aspartate (NMDA). Our data showed that CYT conferred protective effect against loss of cellular viability induced by brief exposure to 200 μM NMDA in a concentration-dependent manner. CYT significantly inhibited the neuronal apoptosis induced by NMDA exposure by reversing intracellular Ca(2+) overload and balancing Bcl-2 and Bax expression levels. Furthermore, CYT significantly reversed the up-regulation of GluN2B-containing NMDA receptors by exposure to NMDA, but it did not affect the level of GluN2A-containing NMDA receptors. These findings suggest that CYT protects cortical neurons, at least partially, by inhibiting the level of GluN2B-containing NMDA receptors and regulating Bcl-2 family.

  3. Erythropoietin-mediated protection of insect brain neurons involves JAK and STAT but not PI3K transduction pathways.

    Science.gov (United States)

    Miljus, N; Heibeck, S; Jarrar, M; Micke, M; Ostrowski, D; Ehrenreich, H; Heinrich, R

    2014-01-31

    The cytokine erythropoietin (Epo) initiates adaptive cellular responses to both moderate environmental challenges and tissue damaging insults in various non-hematopoietic mammalian tissues including the nervous system. Neuroprotective and neuroregenerative functions of Epo in mammals are mediated through receptor-associated Janus kinase 2 and intracellular signaling cascades that modify the transcription of Epo-regulated genes. Signal transducers and activators of transcription (STAT) and phosphoinositol-3-kinase (PI3K) represent key components of two important Epo-induced transduction pathways. Our previous study on insects revealed neuroprotective and regenerative functions of recombinant human Epo (rhEpo) similar to those in mammalian nervous tissues. Here we demonstrate that rhEpo effectively rescues primary cultured locust brain neurons from apoptotic cell death induced by hypoxia or the chemical compound H-7. The Janus kinase inhibitor AG-490 and the STAT inhibitor sc-355797 abolished protective effects of rhEpo on locust brain neurons. In contrast, inhibition of PI3K with LY294002 had no effect on rhEpo-mediated neuroprotection. The results indicate that rhEpo mediates the protection of locust brain neurons through interference with apoptotic pathways by the activation of a Janus kinase-associated receptor and STAT transcription factor(s). The involvement of similar transduction pathways in mammals and insects for the mediation of neuroprotection and support of neural regeneration by Epo indicates that an Epo/Epo receptor-like signaling system with high structural and functional similarity exists in both groups of animals. Epo-like signaling involved in tissue protection appears to be an ancient beneficial function shared by vertebrates and invertebrates.

  4. Protective effect of a prostaglandin I2 analog, TEI-7165, on ischemic neuronal damage in gerbils.

    Science.gov (United States)

    Matsuda, S; Wen, T C; Karasawa, Y; Araki, H; Otsuka, H; Ishihara, K; Sakanaka, M

    1997-09-26

    TTC-909 (Clinprost), a chemically stable PGI2 analog, isocarbacyclin methyl ester (TEI-9090 or Clinprost) incorporated in lipid microspheres, when administered intravenously after brain ischemia, prevents ischemic neuronal damage possibly by modulating cerebral blood flow and platelet aggregation. However, the possibility exists that TEI-7165, which is the free acid form and a central metabolite of TEI-9090, has direct neurotrophic action in vivo, since TEI-7165 has been shown to block neuronal voltage-dependent Ca2+ channels in vitro, and a novel prostacyclin receptor showing high affinity with TEI-7165 has been detected in a variety of brain regions including the hippocampus. In the present study, we infused TEI-7165 for 7 days into the lateral ventricle of gerbils starting 2 h before or just after 3-min forebrain ischemia. TEI-7165 infusion prevented significantly the ischemia-induced shortening of response latency time as revealed by a step-down passive avoidance task. Subsequent light and electron microscopic examinations showed that pyramidal neurons in the hippocampal CA1 region, as well as synapses within the strata moleculare, radiatum and oriens of the region, were significantly more numerous in gerbils infused with TEI-7165 than in those receiving vehicle infusion. TEI-7165 infusion did not affect hippocampal blood flow or temperature. These findings, together with the previously depicted accumulation of centrally administered [3H]TEI-7165 around hippocampal neurons, suggest that TEI-7165 has a direct neuroprotective action in brain ischemia.

  5. A natural compound macelignan protects midbrain dopaminergic neurons from inflammatory degeneration via microglial arginase-1 expression.

    Science.gov (United States)

    Kiyofuji, Kana; Kurauchi, Yuki; Hisatsune, Akinori; Seki, Takahiro; Mishima, Satoshi; Katsuki, Hiroshi

    2015-08-01

    Inflammatory events involving activated microglia have been recognized to play an important role in pathogenesis of various neurodegenerative disorders including Parkinson disease. Compounds regulating activation profiles of microglia may provide therapeutic benefits for Parkinson disease characterized by degeneration of midbrain dopaminergic neurons. Here we examined the effect of macelignan, a compound derived from nutmeg, on inflammatory degeneration of midbrain dopaminergic neurons. Treatment of midbrain slice cultures with interferon (IFN)-γ and lipopolysaccharide (LPS) caused a substantial decrease in viable dopaminergic neurons and an increase in nitric oxide (NO) production indicated by extracellular nitrite accumulation. Application of macelignan (10 μM) concomitantly with LPS prevented the loss of dopaminergic neurons. Besides nitrite accumulation, up-regulation of inducible NO synthase protein expression in response to IFN-γ/LPS was confirmed by Western blotting, and immunohistochemical examination revealed expression of inducible NO synthase in a subpopulation of Iba-1-poitive microglia. However, macelignan did not affect any of these NO-related parameters. On the other hand, macelignan promoted expression of arginase-1 in midbrain slice cultures irrespective of the presence or the absence of IFN-γ/LPS treatment. Arginase-1 expression was mainly localized in a subpopulation of Iba-1-positive cells. Importantly, the neuroprotective effect of macelignan was antagonized by N(ω)-hydroxy-nor-L-arginine, a specific arginase inhibitor. The neuroprotective effect of macelignan was also prevented by GW9662, a peroxisome proliferator-activated receptor γ (PPARγ) antagonist. Overall, these results indicate that macelignan, a compound with PPARγ agonist activity, can provide neuroprotective effect on dopaminergic neurons in an arginase-dependent but NO-independent manner.

  6. Discovery of a novel neuroprotectant, BHDPC, that protects against MPP+/MPTP-induced neuronal death in multiple experimental models.

    Science.gov (United States)

    Chong, Cheong-Meng; Ma, Dan; Zhao, Chao; Franklin, Robin J M; Zhou, Zhong-Yan; Ai, Nana; Li, Chuwen; Yu, Huidong; Hou, Tingjun; Sa, Fei; Lee, Simon Ming-Yuen

    2015-12-01

    Progressive degeneration and death of neurons are main causes of neurodegenerative disorders such as Parkinson's disease and Alzheimer's disease. Although some current medicines may temporarily improve their symptoms, no treatments can slow or halt the progression of neuronal death. In this study, a pyrimidine derivative, benzyl 7-(4-hydroxy-3-methoxyphenyl)-5-methyl-4,7-dihydrotetrazolo[1,5-a]pyrimidine-6-carboxylate (BHDPC), was found to attenuate dramatically the MPTP-induced death of dopaminergic neurons and improve behavior movement deficiency in zebrafish, supporting its potential neuroprotective activity in vivo. Further study in rat organotypic cerebellar cultures indicated that BHDPC was able to suppress MPP(+)-induced cell death of brain tissue slices ex vivo. The protective effect of BHDPC against MPP(+) toxicity was also effective in human neuroblastoma SH-SY5Y cells through restoring abnormal changes in mitochondrial membrane potential and numerous apoptotic regulators. Western blotting analysis indicated that BHDPC was able to activate PKA/CREB survival signaling and further up-regulate Bcl2 expression. However, BHDPC failed to suppress MPP(+)-induced cytotoxicity and the increase of caspase 3 activity in the presence of the PKA inhibitor H89. Taken together, these results suggest that BHDPC is a potential neuroprotectant with prosurvival effects in multiple models of neurodegenerative disease in vitro, ex vivo, and in vivo.

  7. Toxic effects of apomorphine on rat cultured neurons and glial C6 cells, and protection with antioxidants.

    Science.gov (United States)

    dos Santos El-Bachá, R; Daval, J; Koziel, V; Netter, P; Minn, A

    2001-01-01

    Many catechol derivatives are currently used as drugs, even if they produce reactive oxygen species that may cause tissue damage. Among them, apomorphine, a potent dopamine agonist, displays efficient anti-parkinsonian properties, but the consequences of its oxidant and toxic properties have been poorly investigated on in vitro models. In the present work, we investigated apomorphine cytotoxicity by incubating cultures of rat glioma C6 cells and primary cultures of neurons with different concentrations of the drug. Apomorphine-promoted cell death was proportional to its concentration and was time-dependent. The ED(50) of apomorphine on C6 cell death after 48 hr was about 200 microM. The cytotoxic effects induced by apomorphine were correlated to its autoxidation, which leads to the formation of reactive oxygen species, semiquinones, quinones, and a melanin-like pigment. C6 cells that underwent treatment with 400 microM apomorphine for 6 hr displayed features of necrosis, including loss of membrane integrity, degeneration of mitochondria, and DNA fragmentation. Thiols, such as cysteine, N-acetyl-L-cysteine, and glutathione, significantly protected cultured neurons and C6 cells against apomorphine-induced cytotoxicity. Thiols also inhibited apomorphine autoxidation. These data strongly suggest that apomorphine cytotoxicity towards neurons and C6 cells results from an intracellular oxidative stress.

  8. Chronic dietary administration of valproic acid protects neurons of the rat nucleus basalis magnocellularis from ibotenic acid neurotoxicity.

    Science.gov (United States)

    Eleuteri, Simona; Monti, Barbara; Brignani, Sara; Contestabile, Antonio

    2009-02-01

    Valproic acid (VPA) has been used for many years as a drug of choice for epilepsy and mood disorders. Recently, evidence has been proposed for a wide spectrum of actions of this drug, including antitumoral and neuroprotective properties. Valproic acid-mediated neuroprotection in vivo has been so far demonstrated in a limited number of experimental models. In this study, we have tested the neuroprotective potential of chronic (4 + 1 weeks) dietary administration of VPA on degeneration of cholinergic and GABAergic neurons of the rat nucleus basalis magnocellularis (NBM), injected with the excitotoxin, ibotenic acid (IBO), an animal models that is relevant for Alzheimer's disease-like neurodegeneration. We show that VPA treatment significantly protects both cholinergic and GABAergic neurons present in the injected area from the excitotoxic insult. A significant level of neuroprotection, in particular, is exerted towards the cholinergic neurons of the NBM projecting to the cortex, as demonstrated by the substantially higher levels of cholinergic markers maintained in the target cortical area of VPA-treated rats after IBO injection in the NBM. We further show that chronic VPA administration results in increased acetylation of histone H3 in brain, consistent with the histone deacetylase inhibitory action of VPA and putatively linked to a neuroprotective action of the drug mediated at the epigenetic level.

  9. Microglia-induced IL-6 protects against neuronal loss following HSV-1 infection of neural progenitor cells.

    Science.gov (United States)

    Chucair-Elliott, Ana J; Conrady, Christopher; Zheng, Min; Kroll, Chandra M; Lane, Thomas E; Carr, Daniel J J

    2014-09-01

    Herpes virus type 1 (HSV-1) is one of the most widespread human pathogens and accounts for more than 90% of cases of herpes simplex encephalitis (HSE) causing severe and permanent neurologic sequelae among surviving patients. We hypothesize such CNS deficits are due to HSV-1 infection of neural progenitor cells (NPCs). In vivo, HSV-1 infection was found to diminish NPC numbers in the subventricular zone. Upon culture of NPCs in conditions that stimulate their differentiation, we found HSV-1 infection of NPCs resulted in the loss of neuronal precursors with no significant change in the percentage of astrocytes or oligodendrocytes. We propose this is due a direct effect of HSV-1 on neuronal survival without alteration of the differentiation process. The neuronal loss was prevented by the addition of microglia or conditioned media from NPC/microglia co-cultures. Using neutralizing antibodies and recombinant cytokines, we identified interleukin-6 (IL-6) as responsible for the protective effect by microglia, likely through its downstream Signal Transducer and Activator of Transcription 3 (STAT3) cascade.

  10. Bmi1 is down-regulated in the aging brain and displays antioxidant and protective activities in neurons.

    Directory of Open Access Journals (Sweden)

    Mohamed Abdouh

    Full Text Available Aging increases the risk to develop several neurodegenerative diseases, although the underlying mechanisms are poorly understood. Inactivation of the Polycomb group gene Bmi1 in mice results in growth retardation, cerebellar degeneration, and development of a premature aging-like phenotype. This progeroid phenotype is characterized by formation of lens cataracts, apoptosis of cortical neurons, and increase of reactive oxygen species (ROS concentrations, owing to p53-mediated repression of antioxidant response (AOR genes. Herein we report that Bmi1 expression progressively declines in the neurons of aging mouse and human brains. In old brains, p53 accumulates at the promoter of AOR genes, correlating with a repressed chromatin state, down-regulation of AOR genes, and increased oxidative damages to lipids and DNA. Comparative gene expression analysis further revealed that aging brains display an up-regulation of the senescence-associated genes IL-6, p19(Arf and p16(Ink4a, along with the pro-apoptotic gene Noxa, as seen in Bmi1-null mice. Increasing Bmi1 expression in cortical neurons conferred robust protection against DNA damage-induced cell death or mitochondrial poisoning, and resulted in suppression of ROS through activation of AOR genes. These observations unveil that Bmi1 genetic deficiency recapitulates aspects of physiological brain aging and that Bmi1 over-expression is a potential therapeutic modality against neurodegeneration.

  11. Amine-modified single-walled carbon nanotubes protect neurons from injury in a rat stroke model

    Science.gov (United States)

    Lee, Hyun Jung; Park, Jiae; Yoon, Ok Ja; Kim, Hyun Woo; Lee, Do Yeon; Kim, Do Hee; Lee, Won Bok; Lee, Nae-Eung; Bonventre, Joseph V.; Kim, Sung Su

    2011-02-01

    Stroke results in the disruption of tissue architecture and is the third leading cause of death in the United States. Transplanting scaffolds containing stem cells into the injured areas of the brain has been proposed as a treatment strategy, and carbon nanotubes show promise in this regard, with positive outcomes when used as scaffolds in neural cells and brain tissues. Here, we show that pretreating rats with amine-modified single-walled carbon nanotubes can protect neurons and enhance the recovery of behavioural functions in rats with induced stroke. Treated rats showed less tissue damage than controls and took longer to fall from a rotating rod, suggesting better motor functions after injury. Low levels of apoptotic, angiogenic and inflammation markers indicated that amine-modified single-walled carbon nanotubes protected the brains of treated rats from ischaemic injury.

  12. TGFβ1 inhibits IFNγ-mediated microglia activation and protects mDA neurons from IFNγ-driven neurotoxicity.

    Science.gov (United States)

    Zhou, Xiaolai; Zöller, Tanja; Krieglstein, Kerstin; Spittau, Björn

    2015-07-01

    Microglia-mediated neuroinflammation has been reported as a common feature of familial and sporadic forms of Parkinson's disease (PD), and a growing body of evidence indicates that onset and progression of PD correlates with the extent of neuroinflammatory responses involving Interferon γ (IFNγ). Transforming growth factor β1 (TGFβ1) has been shown to be a major player in the regulation of microglia activation states and functions and, thus, might be a potential therapeutic agent by shaping microglial activation phenotypes during the course of neurodegenerative diseases such as PD. In this study, we demonstrate that TGFβ1 is able to block IFNγ-induced microglia activation by attenuating STAT1 phosphorylation and IFNγRα expression. Moreover, we identified a set of genes involved in microglial IFNγ signaling transduction that were significantly down-regulated upon TGFβ1 treatment, resulting in decreased sensitivity of microglia toward IFNγ stimuli. Interestingly, genes mediating negative regulation of IFNγ signaling, such as SOCS2 and SOCS6, were up-regulated after TGFβ1 treatment. Finally, we demonstrate that TGFβ1 is capable of protecting midbrain dopaminergic (mDA) neurons from IFNγ-driven neurotoxicity in mixed neuron-glia cultures derived from embryonic day 14 (E14) midbrain tissue. Together, these data underline the importance of TGFβ1 as a key immunoregulatory factor for microglia by silencing IFNγ-mediated microglia activation and, thereby, rescuing mDA neurons from IFNγ-induced neurotoxicity. Interferon γ (IFNγ) is a potent pro-inflammatory factor that triggers the activation of microglia and the subsequent release of neurotoxic factors. Transforming growth factor β1 (TGFβ1) is able to inhibit the IFNγ-mediated activation of microglia, which is characterized by the release of nitric oxide (NO) and tumor necrosis factor α (TNFα). By decreasing the expression of IFNγ-induced genes as well as the signaling receptor IFNγR1, TGFβ1

  13. Mechanisms of Neuronal Protection against Excitotoxicity, Endoplasmic Reticulum Stress, and Mitochondrial Dysfunction in Stroke and Neurodegenerative Diseases

    Directory of Open Access Journals (Sweden)

    Howard Prentice

    2015-01-01

    Full Text Available In stroke and neurodegenerative disease, neuronal excitotoxicity, caused by increased extracellular glutamate levels, is known to result in calcium overload and mitochondrial dysfunction. Mitochondrial deficits may involve a deficiency in energy supply as well as generation of high levels of oxidants which are key contributors to neuronal cell death through necrotic and apoptotic mechanisms. Excessive glutamate receptor stimulation also results in increased nitric oxide generation which can be detrimental to cells as nitric oxide interacts with superoxide to form the toxic molecule peroxynitrite. High level oxidant production elicits neuronal apoptosis through the actions of proapoptotic Bcl-2 family members resulting in mitochondrial permeability transition pore opening. In addition to apoptotic responses to severe stress, accumulation of misfolded proteins and high levels of oxidants can elicit endoplasmic reticulum (ER stress pathways which may also contribute to induction of apoptosis. Two categories of therapeutics are discussed that impact major pro-death events that include induction of oxidants, calcium overload, and ER stress. The first category of therapeutic agent includes the amino acid taurine which prevents calcium overload and is also capable of preventing ER stress by inhibiting specific ER stress pathways. The second category involves N-methyl-D-aspartate receptor (NMDA receptor partial antagonists illustrated by S-Methyl-N, N-diethyldithiocarbamate sulfoxide (DETC-MeSO, and memantine. DETC-MeSO is protective through preventing excitotoxicity and calcium overload and by blocking specific ER stress pathways. Another NMDA receptor partial antagonist is memantine which prevents excessive glutamate excitation but also remarkably allows maintenance of physiological neurotransmission. Targeting of these major sites of neuronal damage using pharmacological agents is discussed in terms of potential therapeutic approaches for

  14. Protection from neuronal damage induced by combined oxygen and glucose deprivation in organotypic hippocampal cultures by glutamate receptor antagonists.

    Science.gov (United States)

    Strasser, U; Fischer, G

    1995-07-31

    Organotypic hippocampal cultures were exposed to defined periods (30 and 60 min) of combined oxygen and glucose deprivation, mimicking transient ischemic conditions. The involvement of different glutamate receptors in individual hippocampal subfields (CA1, CA3 and dentate gyrus) was studied using antagonists of NMDA (dizocilpine) and AMPA/kainate receptors (CNQX and GYKI 52466). Staining with the fluorescent dye propidium iodide (PI) allowed detection of damaged cells. For quantitative determination of neuronal damage, fluorescence intensity was measured after a 22 h recovery period and was related to maximal fluorescence intensity measured after fixation and PI restaining of the cultures at the end of the experiment. Dizocilpine (10 microM), CNQX (100 microM) and GYKI 52466 (100 microM) provided complete protection in CA1, CA3 and dentate gyrus following the moderate ischemic insult, when the antagonists were present permanently. This indicates that none of the ionotropic glutamate receptor subtypes dominated toxicity in the most sensitive subpopulation of neurons. When applied only during the recovery period protection with dizocilpine (10 microM) or CNQX (100 microM) was drastically reduced by about 60% in the most sensitive area (CA1), but only slightly by 15% in CA3. Therefore the onset of irreversible damage seems to occur earlier in CA1 than in CA3. Blockade of AMPA/kainate receptors by GYKI 52466 (100 microM) offered no neuroprotection if the compound was applied only during the recovery period.(ABSTRACT TRUNCATED AT 250 WORDS)

  15. Absence of glia maturation factor protects dopaminergic neurons and improves motor behavior in mouse model of Parkinsonism

    Science.gov (United States)

    Khan, Mohammad Moshahid; Zaheer, Smita; Ramasamy, Thangavel; Patel, Margi; Kempuraj, Duraisamy; Zaheer, Asgar

    2015-01-01

    Previously, we have shown that aberrant expression of glia maturation factor (GMF), a proinflammatory protein, is associated with the neuropathological conditions underlying diseases suggesting an important role for GMF in neurodegeneration. In the present study, we demonstrate that absence of GMF suppresses dopaminergic (DA) neuron loss, glial activation, and expression of proinflammatory mediators in the substantia nigra pars compacta (SN) and striatum (STR) of 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP) treated mice. Dopaminergic neuron numbers in the SN and fiber densities in the STR were reduced in wild type (Wt) mice when compared with GMF-deficient (GMF-KO) mice after MPTP treatment. We compared the motor abnormalities caused by MPTP treatment in Wt and GMF-KO mice as measured by Rota rod and grip strength test. Results show that the deficits in motor coordination and decrease in dopamine and its metabolite content were protected significantly in GMF-KO mice after MPTP treatment when compared with control Wt mice under identical experimental conditions. These findings were further supported by the immunohistochemical analysis that showed reduced glial activation in the SN of MPTP-treated GMF-KO mice. Similarly, in MPTP-treated GMF-KO mice, production of inflammatory tumor necrosis factor alpha (TNF-α), interleukine-1 beta (IL-1β), granulocyte macrophage-colony stimulating factor (GM-CSF), and the chemokine (C-C motif) ligand 2 (CCL2) MCP-1 was suppressed, findings consistent with a role for GMF in MPTP neurotoxicity. In conclusion, present investigation provides the first evidence that deficiency of GMF protects the DA neuron loss and reduces the inflammatory load following MPTP administration in mice. Thus depletion of endogenous GMF represents an effective and selective strategy to slow down the MPTP-induced neurodegeneration. PMID:25754447

  16. Protective effects of C-phycocyanin against kainic acid-induced neuronal damage in rat hippocampus.

    Science.gov (United States)

    Rimbau, V; Camins, A; Romay, C; González, R; Pallàs, M

    1999-12-03

    The neuroprotective role of C-phycocyanin was examined in kainate-injured brains of rats. The effect of three different treatments with C-phycocyanin was studied. The incidence of neurobehavioral changes was significantly lower in animals receiving C-phycocyanin. These animals also gained significantly more weight than the animals only receiving kainic acid, whereas their weight gain did not differed significantly from controls. Equivalent results were found when the neuronal damage in the hippocampus was evaluated through changes in peripheral benzodiazepine receptors (microglial marker) and heat shock protein 27 kD expression (astroglial marker). Our results are consistent with the oxygen radical scavenging properties of C-phycocyanin described elsewhere. Our findings and the virtual lack of toxicity of C-phycocyanin suggest this drug could be used to treat oxidative stress-induced neuronal injury in neurodegenerative diseases, such as Alzheimer's and Parkinson's.

  17. Protective effect of sodium valproate on motor neurons in the spinal cord following sciatic nerve injury in rats

    Institute of Scientific and Technical Information of China (English)

    Fei Wu; Danmou Xing; Zhengren Peng; Wusheng Kan

    2006-01-01

    /total number of cells× 100%) was calculated.MAIN OUTCOME MEASURES: A value of neurons with positive Bcl-2 expression and apoptotic rate in spinal cord of rats in the two groups.RESULTS: A total of 30 SD rats were involved in the result analysis. ①expression of positive Bcl-2 neurons: A value of positive Bcl-2 neurons were 0.71 ±0.02, 0.86±0.04, 1.02±0.06 at days 4, 7 and 14, respectively after operation in the treatment group, which were obviously higher than those in the model group (0.62±0.03, 0.71±0.05, 0.89±0.04, t = 3.10-4.50, P < 0.05). ②apoptotic result of motor neurons: Apoptotic rate of motor neurons in spinal cord was (6.91±0.89)% and (15.12±2.34)% at days 7 and 14 in the treatment group, which was significantly lower than those in the model group [(9.45±1.61)%, (19.35±0.92)%, t= 2.39, 3.03. P< 0.05].CONCLUSION: VPA can increase expression of Bcl-2 in spinal cord and reduce neuronal apoptosis in rats following sciatic nerve injury, and has protective effect on motor neuron in spinal cord of rats.

  18. Cell division in the CNS: Protective response or lethal event in post-mitotic neurons?

    OpenAIRE

    Yang, Yan; Herrup, Karl

    2007-01-01

    Cell cycle events have been documented to be associated with several human neurodegenerative diseases. This review focuses on two diseases - Alzheimer’s disease and ataxia telangiectasia - as well as their mouse models. Cell cycle studies have shown that ectopic expression of cell cycle markers is spatially and regional correlated well with neuronal cell death in both disease conditions. Further evidence of ectopic cell cycling is found in both human diseases and in its mouse models. These fi...

  19. Protective effect of alpha-synuclein knockdown on methamphetamine-induced neurotoxicity in dopaminergic neurons

    Institute of Scientific and Technical Information of China (English)

    Yunchun Tai; Ling Chen; Enping Huang; Chao Liu; Xingyi Yang; Pingming Qiu; Huijun Wang

    2014-01-01

    The over-expression of α-synuclein is a major factor in the death of dopaminergic neurons in a methamphetamine-induced model of Parkinson’s disease. In the present study, α-synuclein knockdown rats were created by injecting α-synuclein-shRNA lentivirus stereotaxically into the right striatum of experimental rats. At 2 weeks post-injection, the rats were injected intraper-itoneally with methamphetamine to establish the model of Parkinson’s disease. Expression ofα-synuclein mRNA and protein in the right striatum of the injected rats was significantly down-regulated. Food intake and body weight were greater in α-synuclein knockdown rats, and water intake and stereotyped behavior score were lower than in model rats. Striatal dopamine and tyrosine hydroxylase levels were significantly elevated in α-synuclein knockdown rats. Moreover, superoxide dismutase activity was greater in α-synuclein knockdown rat striatum, but the levels of reactive oxygen species, malondialdehyde, nitric oxide synthase and nitrogen monoxide were lower compared with model rats. We also found that α-synuclein knockdown inhibited metham-phetamine-induced neuronal apoptosis. These results suggest that α-synuclein has the capacity to reverse methamphetamine-induced apoptosis of dopaminergic neurons in the rat striatum by inhibiting oxidative stress and improving dopaminergic system function.

  20. Neuronal erythropoietin overexpression protects mice against age-related hearing loss (presbycusis).

    Science.gov (United States)

    Naldi, Arianne Monge; Belfrage, Celina; Jain, Neha; Wei, Eric T; Martorell, Belén Canto; Gassmann, Max; Vogel, Johannes

    2015-12-01

    So far, typical causes of presbycusis such as degeneration of hair cells and/or primary auditory (spiral ganglion) neurons cannot be treated. Because erythropoietin's (Epo) neuroprotective potential has been shown previously, we determined hearing thresholds of juvenile and aged mice overexpressing Epo in neuronal tissues. Behavioral audiometry revealed in contrast to 5 months of age, that 11-month-old Epo-transgenic mice had up to 35 dB lower hearing thresholds between 1.4 and 32 kHz, and at the highest frequencies (50-80 kHz), thresholds could be obtained in aged Epo-transgenic only but not anymore in old C57BL6 control mice. Click-evoked auditory brainstem response showed similar results. Numbers of spiral ganglion neurons in aged C57BL6 but not Epo-transgenic mice were dramatically reduced mainly in the basal turn, the location of high frequencies. In addition, there was a tendency to better preservation of inner and outer hair cells in Epo-transgenic mice. Hence, Epo's known neuroprotective action effectively suppresses the loss of spiral ganglion cells and probably also hair cells and, thus, development of presbycusis in mice.

  1. Antioxidant and Protective Mechanisms against Hypoxia and Hypoglycaemia in Cortical Neurons in Vitro

    Directory of Open Access Journals (Sweden)

    José Joaquín Merino

    2014-02-01

    Full Text Available In the present work, we have studied whether cell death could be induced in cortical neurons from rats subjected to different period of O2 deprivation and low glucose (ODLG. This “in vitro” model is designed to emulate the penumbra area under ischemia. In these conditions, cortical neurons displayed loss of mitochondrial respiratory ability however, nor necrosis neither apoptosis occurred despite ROS production. The absence of cellular death could be a consequence of increased antioxidant responses such as superoxide dismutase-1 (SOD1 and GPX3. In addition, the levels of reduced glutathione were augmented and HIF-1/3α overexpressed. After long periods of ODLG (12–24 h cortical neurons showed cellular and mitochondrial membrane alterations and did not recuperate cellular viability during reperfusion. This could mean that therapies directed toward prevention of cellular and mitochondrial membrane imbalance or cell death through mechanisms other than necrosis or apoptosis, like authophagy, may be a way to prevent ODLG damage.

  2. Simultaneous activation of mitophagy and autophagy by staurosporine protects against dopaminergic neuronal cell death.

    Science.gov (United States)

    Ha, Ji-Young; Kim, Ji-Soo; Kim, Seo-Eun; Son, Jin H

    2014-02-21

    Abnormal autophagy is frequently observed during dopaminergic neurodegeneration in Parkinson's disease (PD). However, it is not yet firmly established whether active autophagy is beneficial or pathogenic with respect to dopaminergic cell loss. Staurosporine, a common inducer of apoptosis, is often used in mechanistic studies of dopaminergic cell death. Here we report that staurosporine activates both autophagy and mitophagy simultaneously during dopaminergic neuronal cell death, and evaluate the physiological significance of these processes during cell death. First, staurosporine treatment resulted in induction of autophagy in more than 75% of apoptotic cells. Pharmacological inhibition of autophagy by bafilomycin A1 decreased significantly cell viability. In addition, staurosporine treatment resulted in activation of the PINK1-Parkin mitophagy pathway, of which deficit underlies some familial cases of PD, in the dopaminergic neuronal cell line, SN4741. The genetic blockade of this pathway by PINK1 null mutation also dramatically increased staurosporine-induced cell death. Taken together, our data suggest that staurosporine induces both mitophagy and autophagy, and that these pathways exert a significant neuroprotective effect, rather than a contribution to autophagic cell death. This model system may therefore be useful for elucidating the mechanisms underlying crosstalk between autophagy, mitophagy, and cell death in dopaminergic neurons.

  3. Ischemic Postconditioning Protects Neuronal Death Caused by Cerebral Ischemia and Reperfusion via Attenuating Protein Aggregation

    Directory of Open Access Journals (Sweden)

    Jianmin Liang, Jihang Yao, Guangming Wang, Ying Wang, Boyu Wang, Pengfei Ge

    2012-01-01

    Full Text Available Objective: To investigate the effect of ischemic postconditioning on protein aggregation caused by transient ischemia and reperfusion and to clarify its underlying mechanism.Methods: Two-vessel-occluded transient global ischemia rat model was used. The rats in ischemic postconditioning group were subjected to three cycles of 30-s/30-s reperfusion/clamping after 15min of ischemia. Neuronal death in the CA1 region was observed by hematoxylin-eosin staining, and number of live neurons was assessed by cell counting under a light microscope. Succinyl-LLVY-AMC was used as substrate to assay proteasome activity in vitro. Protein carbonyl content was spectrophotometrically measured to analyze protein oxidization. Immunochemistry and laser scanning confocal microscopy were used to observe the distribution of ubiquitin in the CA1 neurons. Western blotting was used to analyze the quantitative alterations of protein aggregates, proteasome, hsp70 and hsp40 in cellular fractions under different ischemic conditions.Results: Histological examination showed that the percentage of live neurons in the CA1 region was elevated from 5.21%±1.21% to 55.32%±5.34% after administration of ischemic postconditioning (P=0.0087. Western blotting analysis showed that the protein aggregates in the ischemia group was 32.12±4.87, 41.86±4.71 and 34.51±5.18 times higher than that in the sham group at reperfusion 12h, 24h and 48h, respectively. However, protein aggregates were alleviated significantly by ischemic postconditioning to 2.84±0.97, 13.72±2.13 and 14.37±2.42 times at each indicated time point (P=0.000032, 0.0000051 and 0.0000082. Laser scanning confocal images showed ubiquitin labeled protein aggregates could not be discerned in the ischemic postconditioning group. Further study showed that ischemic postconditioning suppressed the production of carbonyl derivatives, elevated proteasome activity that was damaged by ischemia and reperfusion, increased the expression

  4. Glutamate increases toxicity of inorganic lead in GT1-7 neurons: partial protection induced by flunarizine

    Energy Technology Data Exchange (ETDEWEB)

    Loikkanen, Jarkko; Vaehaekangas, Kirsi H. [Department of Pharmacology and Toxicology, University of Kuopio, PO Box 1627, 70211, Kuopio (Finland); Naarala, Jonne [Department of Environmental Sciences, University of Kuopio, PO Box 1627, 70211, Kuopio (Finland); Savolainen, Kai M. [Department of Industrial Hygiene and Toxicology, Finnish Institute of Occupational Health, Topeliuksenkatu 41 aA, 00250, Helsinki (Finland)

    2003-12-01

    Recent studies point to an interaction between the glutamatergic neurotransmitter system and inorganic lead (Pb) neurotoxicity. Pb (1-100 {mu}M) evoked cytotoxicity over the period of 72 h in mouse hypothalamic GT1-7 neurons. Glutamate (0.1 or 1 mM) on its own did not have any effect on cell viability. However, 1 mM glutamate clearly increased Pb-induced cell death at 48 and 72 h. Although flunarizine (0.1-10 {mu}M), an antagonist of L- and T-type voltage-sensitive calcium channels (VSCCs), partially protected from the cytotoxicity induced by co-exposure to Pb (10 or 100 {mu}M) and glutamate (1 mM), it had no protective effect on cytotoxicity induced by Pb alone. The flunarizine-induced protection was dependent on time and observed only at 48 h. Neither verapamil, an antagonist of L-type VSCCs, nor DIDS, an inhibitor of anion exchange, at non-toxic concentrations (0.1-10 {mu}M) had any effect on cytotoxicity induced by Pb alone or together with glutamate at any studied time point. Co-exposure to Pb and glutamate also resulted in more prominent production of reactive oxygen species (ROS) than either of the compounds alone. Interestingly, we observed an increase in intracellular glutathione (GSH) levels in cells exposed to micromolar concentrations of Pb. Glutamate decreased the levels of intracellular GSH and also partially reduced the Pb-induced increase in GSH levels. These results suggest that the interaction of glutamate and Pb results in increased neuronal cell death via mechanisms that involve an increase in ROS production, a decrease in intracellular GSH defense against oxidative stress and probably T-type VSCCs. (orig.)

  5. Protective effect of alpha-synuclein knockdown on methamphetamine-induced neurotoxicity in dopaminergic neurons

    OpenAIRE

    Tai, Yunchun; Chen, Ling; Huang, Enping; Liu, Chao; Yang, Xingyi; Qiu, Pingming; Wang, Huijun

    2014-01-01

    The over-expression of α-synuclein is a major factor in the death of dopaminergic neurons in a methamphetamine-induced model of Parkinson's disease. In the present study, α-synuclein knockdown rats were created by injecting α-synuclein-shRNA lentivirus stereotaxically into the right striatum of experimental rats. At 2 weeks post-injection, the rats were injected intraperitoneally with methamphetamine to establish the model of Parkinson's disease. Expression of α-synuclein mRNA and protein in ...

  6. Protective action of green tea catechins in neuronal mitochondria during aging.

    Science.gov (United States)

    Assuncao, Marco; Andrade, Jose Paulo

    2015-01-01

    Mitochondria are central players in the regulation of cell homeostasis. They are essential for energy production but at the same time, reactive oxygen species accumulate as byproducts of the electron transport chain causing mitochondrial damage. In the central nervous system, senescence and neurodegeneration occur as a consequence of mitochondrial oxidative insults and impaired electron transfer. The accumulation of several oxidation products in neurons during aging prompts the idea that consumption of antioxidant compounds may delay neurodegenerative processes. Tea, one of the most consumed beverages in the world, presents benefits to human health that have been associated to its abundance in polyphenols, mainly catechins, that possess powerful antioxidant properties in vivo and in vitro. In this review, the focus will be placed on the effects of green tea catechins in neuronal mitochondria. Although these compounds reach the brain in small quantities, there are several possible targets, signaling pathways and molecular machinery impinging in the mitochondria that will be highlighted. Accumulated evidence thus far seems to indicate that catechins help prevent neurodegeneration and delay brain function decline.

  7. L-Lactate protects neurons against excitotoxicity: implication of an ATP-mediated signaling cascade

    KAUST Repository

    Jourdain, P.

    2016-02-19

    Converging experimental data indicate a neuroprotective action of L-Lactate. Using Digital Holographic Microscopy, we observe that transient application of glutamate (100 μM; 2 min) elicits a NMDA-dependent death in 65% of mouse cortical neurons in culture. In the presence of L-Lactate (or Pyruvate), the percentage of neuronal death decreases to 32%. UK5099, a blocker of the Mitochondrial Pyruvate Carrier, fully prevents L-Lactate-mediated neuroprotection. In addition, L-Lactate-induced neuroprotection is not only inhibited by probenicid and carbenoxolone, two blockers of ATP channel pannexins, but also abolished by apyrase, an enzyme degrading ATP, suggesting that ATP produced by the Lactate/Pyruvate pathway is released to act on purinergic receptors in an autocrine/paracrine manner. Finally, pharmacological approaches support the involvement of the P2Y receptors associated to the PI3-kinase pathway, leading to activation of KATP channels. This set of results indicates that L-Lactate acts as a signalling molecule for neuroprotection against excitotoxicity through coordinated cellular pathways involving ATP production, release and activation of a P2Y/KATP cascade.

  8. Point application with Angong Niuhuang sticker protects hippocampal and cortical neurons in rats with cerebral ischemia

    Directory of Open Access Journals (Sweden)

    Dong-shu Zhang

    2015-01-01

    Full Text Available Angong Niuhuang pill, a Chinese materia medica preparation, can improve neurological functions after acute ischemic stroke. Because of its inconvenient application and toxic components (Cinnabaris and Realgar, we used transdermal enhancers to deliver Angong Niuhuang pill by modern technology, which expanded the safe dose range and clinical indications. In this study, Angong Niuhuang stickers administered at different point application doses (1.35, 2.7, and 5.4 g/kg were administered to the Dazhui (DU14, Qihai (RN6 and Mingmen (DU4 of rats with chronic cerebral ischemia, for 4 weeks. The Morris water maze was used to determine the learning and memory ability of rats. Hematoxylin-eosin staining and Nissl staining were used to observe neuronal damage of the cortex and hippocampal CA1 region in rats with chronic cerebral ischemia. The middle- and high-dose point application of Angong Niuhuang stickers attenuated neuronal damage in the cortex and hippocampal CA1 region, and improved the memory of rats with chronic cerebral ischemia with an efficacy similar to interventions by electroacupuncture at Dazhui (DU14, Qihai (RN6 and Mingmen (DU4. Our experimental findings indicate that point application with Angong Niuhuang stickers can improve cognitive function after chronic cerebral ischemia in rats and is neuroprotective with an equivalent efficacy to acupuncture.

  9. Galanin Protects from Caspase-8/12-initiated Neuronal Apoptosis in the Ischemic Mouse Brain via GalR1

    Science.gov (United States)

    Li, Yun; Mei, Zhu; Liu, Shuiqiao; Wang, Tong; Li, Hui; Li, Xiao-Xiao; Han, Song; Yang, Yutao; Li, Junfa; Xu, Zhi-Qing David

    2017-01-01

    Galanin (GAL) plays key role in many pathophysiological processes, but its role in ischemic stroke remains unclear. Here, the models of 1 h middle cerebral artery occlusion (MCAO)/1-7 d reperfusion (R)-induced ischemic stroke and in vitro cell ischemia of 1 h oxygen-glucose deprivation (OGD)/24 h reoxygenation in primary cultured cortical neurons were used to explore GAL’s effects and its underlying mechanisms. The results showed significant increases of GAL protein levels in the peri-infarct region (P) and infarct core (I) within 48 h R of MCAO mice (p<0.001). The RT-qPCR results also demonstrated significant increases of GAL mRNA during 24-48 h R (p<0.001), and GAL receptors GalR1-2 (but not 3) mRNA levels in the P region at 24 h R of MCAO mice (p<0.001). Furthermore, the significant decrease of infarct volume (p<0.05) and improved neurological outcome (p<0.001-0.05) were observed in MCAO mice following 1 h pre- or 6 h post-treatment of GAL during 1-7 d reperfusion. GalR1 was confirmed as the receptor responsible for GAL-induced neuroprotection by using GalR2/3 agonist AR-M1896 and Lentivirus-based RNAi knockdown of GalR1. GAL treatment inhibited Caspase-3 activation through the upstream initiators Capsases-8/-12 (not Caspase-9) in both P region and OGD-treated cortical neurons. Meanwhile, GAL’s neuroprotective effect was not observed in cortical neurons from conventional protein kinase C (cPKC) γ knockout mice. These results suggested that exogenous GAL protects the brain from ischemic injury by inhibiting Capsase-8/12-initiated apoptosis, possibly mediated by GalR1 via the cPKCγ signaling pathway. PMID:28203483

  10. Eriocaulon buergerianum extract protects PC12 cells and neurons in zebrafish against 6-hydroxydopamine-induced damage

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    Lin Zhixiu

    2011-04-01

    Full Text Available Abstract Background Ericaulon buergerianum (Gujingcao is an ophthalmic, anti-inflammatory and antimicrobial Chinese medicinal herb. This study aims to investigate the neuroprotective effects of Ericaulon buergerianum ethanol extract (EBE and to elucidate its underlying action mechanism. Methods The viability of dopaminergic (DA neuron in zebrafish was examined by anti-tyrosine hydroxylase (TH immunostaining. The locomotor activity of zebrafish was assessed with a digital video tracking system. The viability and cellular damage of the PC12 cells were determined by MTT and LDH assays respectively. The nuclear morphological changes in apoptotic cells were evaluated with DNA staining by Hoechst 33342 dye. Intracellular nitric oxide (NO was quantified by DAF-FM diacetate staining. The expression of inducible nitric oxide synthase (iNOS was determined by Western blot. Results EBE inhibited the 6-OHDA-induced decrease in total distance of movement in zebrafish. Pretreatments of EBE (25, 50, 100 and 200 μg/ml increased the viability of 6-OHDA-damaged PC12 cells in a dose dependent manner. Protection against 6-OHDA-induced nuclear fragmentation and accumulation of apoptotic bodies was also observed in EBE pretreated cells. Anti-oxidative (inhibition of NO production and iNOS expression in PC12 cells in vitro activities of EBE are related to its neuroprotective effects in 6-OHDA-induced DA neuron damage. Conclusion EBE exhibited significant neuroprotective activities in zebrafish, including recovery of dopaminergic neuron loss caused by 6-OHDA in a dose-dependent manner in vivo, inhibition of 6-OHDA-induced decrease of total distance in movement in zebrafish. The iNOS-NO pathway may be involved.

  11. The c-Abl inhibitor, Nilotinib, protects dopaminergic neurons in a preclinical animal model of Parkinson's disease

    Science.gov (United States)

    Karuppagounder, Senthilkumar S.; Brahmachari, Saurav; Lee, Yunjong; Dawson, Valina L.; Dawson, Ted M.; Ko, Han Seok

    2014-01-01

    c-Abl is activated in the brain of Parkinson's disease (PD) patients and in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-intoxicated mice where it inhibits parkin through tyrosine phosphorylation leading to the accumulation of parkin substrates, and neuronal cell death. In the present study, we evaluated the in vivo efficacy of nilotinib, a brain penetrant c-Abl inhibitor, in the acute MPTP-induced model of PD. Our results show that administration of nilotinib reduces c-Abl activation and the levels of the parkin substrate, PARIS, resulting in prevention of dopamine (DA) neuron loss and behavioral deficits following MPTP intoxication. On the other hand, we observe no reduction in the tyrosine phosphorylation of parkin and the parkin substrate, AIMP2 suggesting that the protective effect of nilotinib may, in part, be parkin-independent or to the pharmacodynamics properties of nilotinib. This study provides a strong rationale for testing other brain permeable c-Abl inhibitors as potential therapeutic agents for the treatment of PD. PMID:24786396

  12. Blockade of the Interaction of Calcineurin with FOXO in Astrocytes Protects Against Amyloid-β-Induced Neuronal Death.

    Science.gov (United States)

    Fernandez, Ana M; Hervas, Ruben; Dominguez-Fraile, Manuel; Garrido, Victoria Navarro; Gomez-Gutierrez, Patricia; Vega, Miguel; Vitorica, Javier; Perez, Juan J; Torres Aleman, Ignacio

    2016-04-12

    Astrocytes actively participate in neuro-inflammatory processes associated to Alzheimer's disease (AD), and other brain pathologies. We recently showed that an astrocyte-specific intracellular signaling pathway involving an interaction of the phosphatase calcineurin with the transcription factor FOXO3 is a major driver in AD-associated pathological inflammation, suggesting a potential new druggable target for this devastating disease. We have now developed decoy molecules to interfere with calcineurin/FOXO3 interactions, and tested them in astrocytes and neuronal co-cultures exposed to amyloid-β (Aβ) toxicity. We observed that interference of calcineurin/FOXO3 interactions exerts a protective action against Aβ-induced neuronal death and favors the production of a set of growth factors that we hypothesize form part of a cytoprotective pathway to resolve inflammation. Furthermore, interference of the Aβ-induced interaction of calcineurin with FOXO3 by decoy compounds significantly decreased amyloid-β protein precursor (AβPP) synthesis, reduced the AβPP amyloidogenic pathway, resulting in lower Aβ levels, and blocked the expression of pro-inflammatory cytokines TNFα and IL-6 in astrocytes. Collectively, these data indicate that interrupting pro-inflammatory calcineurin/FOXO3 interactions in astrocytes triggered by Aβ accumulation in brain may constitute an effective new therapeutic approach in AD. Future studies with intranasal delivery, or brain barrier permeable decoy compounds, are warranted.

  13. Protective Effects of Testosterone on Presynaptic Terminals against Oligomeric β-Amyloid Peptide in Primary Culture of Hippocampal Neurons

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    Chi-Fai Lau

    2014-01-01

    Full Text Available Increasing lines of evidence support that testosterone may have neuroprotective effects. While observational studies reported an association between higher bioavailable testosterone or brain testosterone levels and reduced risk of Alzheimer’s disease (AD, there is limited understanding of the underlying neuroprotective mechanisms. Previous studies demonstrated that testosterone could alleviate neurotoxicity induced by β-amyloid (Aβ, but these findings mainly focused on neuronal apoptosis. Since synaptic dysfunction and degeneration are early events during the pathogenesis of AD, we aim to investigate the effects of testosterone on oligomeric Aβ-induced synaptic changes. Our data suggested that exposure of primary cultured hippocampal neurons to oligomeric Aβ could reduce the length of neurites and decrease the expression of presynaptic proteins including synaptophysin, synaptotagmin, and synapsin-1. Aβ also disrupted synaptic vesicle recycling and protein folding machinery. Testosterone preserved the integrity of neurites and the expression of presynaptic proteins. It also attenuated Aβ-induced impairment of synaptic exocytosis. By using letrozole as an aromatase antagonist, we further demonstrated that the effects of testosterone on exocytosis were unlikely to be mediated through the estrogen receptor pathway. Furthermore, we showed that testosterone could attenuate Aβ-induced reduction of HSP70, which suggests a novel mechanism that links testosterone and its protective function on Aβ-induced synaptic damage. Taken together, our data provide further evidence on the beneficial effects of testosterone, which may be useful for future drug development for AD.

  14. Atomistic MD simulations reveal the protective role of cholesterol in dimeric beta-amyloid induced disruptions in neuronal membrane mimics

    Science.gov (United States)

    Qiu, Liming; Buie, Creighton; Cheng, Sara; Chou, George; Vaughn, Mark; Cheng, K.

    2011-10-01

    Interactions of oligomeric beta-amyloid peptides with neuronal membranes have been linked to the pathogenesis of Alzheimer's disease (AD). The molecular details of the interactions of different lipid components, particularly cholesterol (CHOL), of the membranes with the peptides are not clear. Using an atomistic MD simulations approach, the water permeability barrier, structural geometry and order parameters of binary phosphatidylcholine (PC) and PC/CHOL lipid bilayers were examined from various 200 ns-simulation replicates. Our results suggest that the longer length dimer (2 x 42 residues) perturbs the membrane more than the shorter one (2 x 40 residues). In addition, we discovered a significant protective role of cholesterol in protein-induced disruptions of the membranes. The use of a new Monte-Carlo method in characterizing the structures of the conformal annular lipids in close proximity with the proteins will be introduced. We propose that the neurotoxicity of beta-amyloid peptide may be associated with the nanodomain or raft-like structures of the neuronal membranes in-vivo in the development of AD.

  15. Magnolol reduces glutamate-induced neuronal excitotoxicity and protects against permanent focal cerebral ischemia up to 4 hours.

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    Wei-Ting Lee

    Full Text Available Neuroprotective efficacy of magnolol, 5,5'-dially-2,2'-dihydroxydiphenyl, was investigated in a model of stroke and cultured neurons exposed to glutamate-induced excitotoxicity. Rats were subjected to permanent middle cerebral artery occlusion (pMCAO. Magnolol or vehicle was administered intraperitoneally, at 1 hr pre-insult or 1-6 hrs post-insult. Brain infarction was measured upon sacrifice. Relative to controls, animals pre-treated with magnolol (50-200 mg/kg had significant infarct volume reductions by 30.9-37.8% and improved neurobehavioral outcomes (P<0.05, respectively. Delayed treatment with magnolol (100 mg/kg also protected against ischemic brain damage and improved neurobehavioral scores, even when administered up to 4 hrs post-insult (P<0.05, respectively. Additionally, magnolol (0.1 µM effectively attenuated the rises of intracellular Ca(2+ levels, [Ca(2+](i, in cultured neurons exposed to glutamate. Consequently, magnolol (0.1-1 µM significantly attenuated glutamate-induced cytotoxicity and cell swelling (P<0.05. Thus, magnolol offers neuroprotection against permanent focal cerebral ischemia with a therapeutic window of 4 hrs. This neuroprotection may be, partly, mediated by its ability to limit the glutamate-induced excitotoxicity.

  16. Protection of signal processing at low temperature in baroreceptive neurons in the nucleus tractus solitarius of Syrian hamsters, a hibernating species

    Science.gov (United States)

    Sekizawa, Shin-Ichi; Horwitz, Barbara A.; Horowitz, John M.

    2013-01-01

    We previously described synaptic currents between baroreceptor fibers and second-order neurons in the nucleus tractus solitarius (NTS) that were larger in Syrian hamsters than in rats. This suggested that although electrical activity throughout the hamster brain decreased as brain temperature declined, the greater synaptic input to its NTS would support continued operation of cardiorespiratory reflexes at low body temperatures. Here, we focused on properties that would protect these neurons against potential damage from the larger synaptic inputs, testing the hypotheses that hamster NTS neurons exhibit: 1) intrinsic N-methyl-d-aspartate receptor (NMDAR) properties that limit Ca2+ influx to a greater degree than do rat NTS neurons and 2) properties that reduce gating signals to NMDARs to a greater degree than in rat NTS neurons. Whole cell patch-clamp recordings on anatomically identified second-order NTS baroreceptive neurons showed that NMDAR-mediated synaptic currents between sensory fibers and second-order NTS neurons were larger in hamsters than in rats at 33°C and 15°C, with no difference in their permeability to Ca2+. However, at 15°C, but not at 33°C, non-NMDAR currents evoked by glutamate released from baroreceptor fibers had significantly shorter durations in hamsters than in rats. Thus, hamster NMDARs did not exhibit lower Ca2+ influx than did rats (negating hypothesis 1), but they did exhibit significant differences in non-NMDAR neuronal properties at low temperature (consistent with hypothesis 2). The latter (shorter duration of non-NMDAR currents) would likely limit NMDAR coincidence gating and may help protect hamster NTS neurons, enabling them to contribute to signal processing at low body temperatures. PMID:24068050

  17. Protection against Oxygen-Glucose Deprivation/Reperfusion Injury in Cortical Neurons by Combining Omega-3 Polyunsaturated Acid with Lyciumbarbarum Polysaccharide.

    Science.gov (United States)

    Shi, Zhe; Wu, Di; Yao, Jian-Ping; Yao, Xiaoli; Huang, Zhijian; Li, Peng; Wan, Jian-Bo; He, Chengwei; Su, Huanxing

    2016-01-13

    Ischemic stroke, characterized by the disturbance of the blood supply to the brain, is a severe worldwide health threat with high mortality and morbidity. However, there is no effective pharmacotherapy for ischemic injury. Currently, combined treatment is highly recommended for this devastating injury. In the present study, we investigated neuroprotective effects of the combination of omega-3 polyunsaturated fatty acids (ω-3 PUFAs) and Lyciumbarbarum polysaccharide (LBP) on cortical neurons using an in vitro ischemic model. Our study demonstrated that treatment with docosahexaenoic acid (DHA), a major component of the ω-3 PUFAs family, significantly inhibited the increase of intracellular Ca(2+) in cultured wild type (WT) cortical neurons subjected to oxygen-glucose deprivation/reperfusion (OGD/R) injury and promoted their survival compared with the vehicle-treated control. The protective effects were further confirmed in cultured neurons with high endogenous ω-3 PUFAs that were isolated from fat-1 mice, in that a higher survival rate was found in fat-1 neurons compared with wild-type neurons after OGD/R injury. Our study also found that treatment with LBP (50 mg/L) activated Trk-B signaling in cortical neurons and significantly attenuated OGD/R-induced cell apoptosis compared with the control. Notably, both combining LBP treatment with ω-3 PUFAs administration to WT neurons and adding LBP to fat-1 neurons showed enhanced effects on protecting cortical neurons against OGD/R injury via concurrently regulating the intracellular calcium overload and neurotrophic pathway. The results of the study suggest that ω-3 PUFAs and LBP are promising candidates for combined pharmacotherapy for ischemic stroke.

  18. Protection of neurons in the retinal ganglion cell layer against excitotoxicity by the N-acylethanolamine, N-linoleoylethanolamine

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    Duncan RS

    2011-04-01

    Full Text Available R. Scott Duncan1,*, Hua Xin1,*, Daryl L Goad1, Kent D Chapman2,3, Peter Koulen1,31Vision Research Center and Departments of Ophthalmology and Basic Medical Science, School of Medicine, University of Missouri, Kansas City, MO, USA; 2Department of Biological Sciences, University of North Texas, Denton, TX, USA; 3Center for Plant Lipid Research, University of North Texas, Denton, TX, USA *Authors contributed equallyAbstract: Retinal ganglion cell (RGC death is a hallmark of neurodegenerative diseases and disease processes of the eye, including glaucoma. The protection of RGCs has been an important strategy for combating glaucoma, but little clinical success has been reported to date. One pathophysiological consequence of glaucoma is excessive extracellular glutamate subsequently leading to excitotoxicity in the retina. Endocannabinoids, such as the N-acylethanolamine (NAE, arachidonylethanolamine (NAE 20:4, exhibit neuroprotective properties in some models of neurodegenerative disease. The majority of NAEs, however, are not cannabinoids, and their physiological function is not clear. Here, we determined whether the noncannabinoid NAE, linoleoylethanolamine (NAE18:2, protects neurons in the RGC layer against glutamate excitotoxicity in ex-vivo retina cultures. Using a terminal deoxynucleotidyl transferase-mediated dUTP (2´-deoxyuridine 5´-triphosphate nick-end labeling (TUNEL assay, we determined that NAE18:2 reduces the number of apoptotic RGC layer neurons in response to glutamate and conclude that NAE18:2 is a neuroprotective compound with potential for treating glaucomatous retinopathy.Keywords: neuroprotection, glutamate, calcium signaling, immunocytochemistry, eye, vision, glaucoma.

  19. Tetanus Toxin Hc Fragment Induces the Formation of Ceramide Platforms and Protects Neuronal Cells against Oxidative Stress.

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    Roger Cubí

    Full Text Available Tetanus toxin (TeTx is the protein, synthesized by the anaerobic bacteria Clostridium tetani, which causes tetanus disease. TeTx gains entry into target cells by means of its interaction with lipid rafts, which are membrane domains enriched in sphingomyelin and cholesterol. However, the exact mechanism of host membrane binding remains to be fully established. In the present study we used the recombinant carboxyl terminal fragment from TeTx (Hc-TeTx, the domain responsible for target neuron binding, showing that Hc-TeTx induces a moderate but rapid and sustained increase in the ceramide/sphingomyelin ratio in primary cultures of cerebellar granule neurons and in NGF-differentiated PC12 cells, as well as induces the formation of ceramide platforms in the plasma membrane. The mentioned increase is due to the promotion of neutral sphingomyelinase activity and not to the de novo synthesis, since GW4869, a specific neutral sphingomyelinase inhibitor, prevents neutral sphingomyelinase activity increase and formation of ceramide platforms. Moreover, neutral sphingomyelinase inhibition with GW4869 prevents Hc-TeTx-triggered signaling (Akt phosphorylation, as well as the protective effect of Hc-TeTx on PC12 cells subjected to oxidative stress, while siRNA directed against nSM2 prevents protection by Hc-TeTx of NSC-34 cells against oxidative insult. Finally, neutral sphingomyelinase activity seems not to be related with the internalization of Hc-TeTx into PC12 cells. Thus, the presented data shed light on the mechanisms triggered by TeTx after membrane binding, which could be related with the events leading to the neuroprotective action exerted by the Hc-TeTx fragment.

  20. Inhibition of tumor necrosis factor-alpha by sodium ferulate in protecting neurons from beta-amyloid induced damage

    Institute of Scientific and Technical Information of China (English)

    Suyan Yao; Deyu Zheng; Zhuo Liu; Ying Jin

    2006-01-01

    -induced released LDH and reduce MAP-2 expression, so as to play a key role in protecting the neurons against the Aβ impairments. The effect is characterized by dosage dependence.

  1. Low-Dose Ethanol Preconditioning Protects Against Oxygen-Glucose Deprivation/Reoxygenation-Induced Neuronal Injury By Activating Large Conductance, Ca(2+)-Activated K(+) Channels In Vitro.

    Science.gov (United States)

    Su, Fang; Guo, An-Chen; Li, Wei-Wei; Zhao, Yi-Long; Qu, Zheng-Yi; Wang, Yong-Jun; Wang, Qun; Zhu, Yu-Lan

    2017-02-01

    Increasing evidence suggests that low to moderate ethanol ingestion protects against the deleterious effects of subsequent ischemia/reperfusion; however, the underlying mechanism has not been elucidated. In the present study, we showed that expression of the neuronal large-conductance, Ca(2+)-activated K(+) channel (BKCa) α-subunit was upregulated in cultured neurons exposed to oxygen-glucose deprivation/reoxygenation (OGD/R) compared with controls. Preconditioning with low-dose ethanol (10 mmol/L) increased cell survival rate in neurons subjected to OGD/R, attenuated the OGD/R-induced elevation of cytosolic Ca(2+) levels, and reduced the number of apoptotic neurons. Western blots revealed that ethanol preconditioning upregulated expression of the anti-apoptotic protein Bcl-2 and downregulated the pro-apoptotic protein Bax. The protective effect of ethanol preconditioning was antagonized by a BKCa channel inhibitor, paxilline. Inside-out patches in primary neurons also demonstrated the direct activation of the BKCa channel by 10 mmol/L ethanol. The above results indicated that low-dose ethanol preconditioning exerts its neuroprotective effects by attenuating the elevation of cytosolic Ca(2+) and preventing neuronal apoptosis, and this is mediated by BKCa channel activation.

  2. Interleukin-1beta but not tumor necrosis factor-alpha potentiates neuronal damage by quinolinic acid: protection by an adenosine A2A receptor antagonist.

    Science.gov (United States)

    Stone, Trevor W; Behan, Wilhelmina M H

    2007-04-01

    Quinolinic acid is an agonist at glutamate receptors sensitive to N-methyl-D-aspartate (NMDA). It has been implicated in neural dysfunction associated with infections, trauma, and ischemia, although its neurotoxic potency is relatively low. This study was designed to examine the effects of a combination of quinolinic acid and the proinflammatory cytokines interleukin-1beta (IL-1beta) and tumor necrosis factor-alpha (TNF-alpha). Compounds were administered to the hippocampus of anesthetized male rats, animals being allowed to recover for 7 days before histological analysis of the hippocampus for neuronal damage estimated by counting of intact, healthy neurons. A low dose of quinolinic acid or IL-1beta produced no damage by itself, but the two together induced a significant loss of pyramidal neurons in the hippocampus. Higher doses produced almost total loss of pyramidal cells. Intrahippocampal TNF-alpha produced no effect alone but significantly reduced the neuronal loss produced by quinolinic acid. The adenosine A(2A) receptor antagonist ZM241385 reduced neuronal loss produced by the combinations of quinolinic acid and IL-1beta. The results suggest that simultaneous quinolinic acid and IL-1beta, both being induced by cerebral infection or injury, are synergistic in the production of neuronal damage and could together contribute substantially to traumatic, infective, or ischemic cerebral damage. Antagonism of adenosine A(2A) receptors protects neurons against the combination of quinolinic acid and IL-1beta.

  3. Protective Effect of Antioxidants on Neuronal Dysfunction and Plasticity in Huntington's Disease

    Science.gov (United States)

    Velusamy, Thirunavukkarasu; Panneerselvam, Archana S.; Purushottam, Meera; Anusuyadevi, Muthuswamy; Pal, Pramod Kumar; Jain, Sanjeev; Essa, Musthafa Mohamed

    2017-01-01

    Huntington's disease (HD) is characterised by movement disorders, cognitive impairments, and psychiatric problems. The abnormal generation of reactive oxygen species and the resulting oxidative stress-induced mitochondrial damage in neurons upon CAG mutations in the HTT gene have been hypothesized as the contributing factors of neurodegeneration in HD. The potential use of antioxidants against free radical toxicity has been an emerging field in the management of ageing and many neurodegenerative disorders. Neural stem cells derived adult neurogenesis represents the regenerative capacity of the adult brain. The process of adult neurogenesis has been implicated in the cognitive functions of the brain and is highly modulated positively by different factors including antioxidants. The supportive role of antioxidants to reduce the severity of HD via promoting the functional neurogenesis and neuroprotection in the pathological adult brain has great promise. This review comprehends the recent studies describing the therapeutic roles of antioxidants in HD and other neurologic disorders and highlights the scope of using antioxidants to promote adult neurogenesis in HD. It also advocates a new line of research to delineate the mechanisms by which antioxidants promote adult neurogenesis in HD. PMID:28168008

  4. Rhinacanthus nasutus protects cultured neuronal cells against hypoxia induced cell death.

    Science.gov (United States)

    Brimson, James M; Tencomnao, Tewin

    2011-07-26

    Rhinacanthus nasutus (L.) Kurz (Acanthaceae) is an herb native to Thailand and Southeast Asia, known for its antioxidant properties. Hypoxia leads to an increase in reactive oxygen species in cells and is a leading cause of neuronal damage. Cell death caused by hypoxia has been linked with a number of neurodegenerative diseases including some forms of dementia and stroke, as well as the build up of reactive oxygen species which can lead to diseases such as Huntington's disease, Parkinson's disease and Alzeheimer's disease. In this study we used an airtight culture container and the Mitsubishi Gas Company anaeropack along with the MTT assay, LDH assay and the trypan blue exlusion assay to show that 1 and 10 µg mL⁻¹ root extract of R. nasutus is able to significantly prevent the death of HT-22 cells subjected to hypoxic conditions, and 0.1 to 10 µg mL⁻¹ had no toxic effect on HT-22 under normal conditions, whereas 100 µg mL⁻¹ reduced HT-22 cell proliferation. We also used H₂DCFDA staining to show R. nasutus can reduce reactive oxygen species production in HT-22 cells.

  5. Rhinacanthus nasutus Protects Cultured Neuronal Cells against Hypoxia Induced Cell Death

    Directory of Open Access Journals (Sweden)

    James M. Brimson

    2011-07-01

    Full Text Available Rhinacanthus nasutus (L. Kurz (Acanthaceae is an herb native to Thailand and Southeast Asia, known for its antioxidant properties. Hypoxia leads to an increase in reactive oxygen species in cells and is a leading cause of neuronal damage. Cell death caused by hypoxia has been linked with a number of neurodegenerative diseases including some forms of dementia and stroke, as well as the build up of reactive oxygen species which can lead to diseases such as Huntington’s disease, Parkinson’s disease and Alzeheimer’s disease. In this study we used an airtight culture container and the Mitsubishi Gas Company anaeropack along with the MTT assay, LDH assay and the trypan blue exlusion assay to show that 1 and 10 µg mL−1 root extract of R. nasutus is able to significantly prevent the death of HT-22 cells subjected to hypoxic conditions, and 0.1 to 10 µg mL−1 had no toxic effect on HT-22 under normal conditions, whereas 100 µg mL−1 reduced HT-22 cell proliferation. We also used H2DCFDA staining to show R. nasutus can reduce reactive oxygen species production in HT-22 cells.

  6. Prototypical antipsychotic drugs protect hippocampal neuronal cultures against cell death induced by growth medium deprivation

    Directory of Open Access Journals (Sweden)

    Williams Sylvain

    2006-03-01

    Full Text Available Abstract Background Several clinical studies suggested that antipsychotic-based medications could ameliorate cognitive functions impaired in certain schizophrenic patients. Accordingly, we investigated the effects of various dopaminergic receptor antagonists – including atypical antipsychotics that are prescribed for the treatment of schizophrenia – in a model of toxicity using cultured hippocampal neurons, the hippocampus being a region of particular relevance to cognition. Results Hippocampal cell death induced by deprivation of growth medium constituents was strongly blocked by drugs including antipsychotics (10-10-10-6 M that display nM affinities for D2 and/or D4 receptors (clozapine, haloperidol, (±-sulpiride, domperidone, clozapine, risperidone, chlorpromazine, (+-butaclamol and L-741,742. These effects were shared by some caspases inhibitors and were not accompanied by inhibition of reactive oxygen species. In contrast, (--raclopride and remoxipride, two drugs that preferentially bind D2 over D4 receptors were ineffective, as well as the selective D3 receptor antagonist U 99194. Interestingly, (--raclopride (10-6 M was able to block the neuroprotective effect of the atypical antipsychotic clozapine (10-6 M. Conclusion Taken together, these data suggest that D2-like receptors, particularly the D4 subtype, mediate the neuroprotective effects of antipsychotic drugs possibly through a ROS-independent, caspase-dependent mechanism.

  7. Major histocompatibility complex class I molecules protect motor neurons from astrocyte-induced toxicity in amyotrophic lateral sclerosis.

    Science.gov (United States)

    Song, SungWon; Miranda, Carlos J; Braun, Lyndsey; Meyer, Kathrin; Frakes, Ashley E; Ferraiuolo, Laura; Likhite, Shibi; Bevan, Adam K; Foust, Kevin D; McConnell, Michael J; Walker, Christopher M; Kaspar, Brian K

    2016-04-01

    Astrocytes isolated from individuals with amyotrophic lateral sclerosis (ALS) are toxic to motor neurons (MNs) and play a non-cell autonomous role in disease pathogenesis. The mechanisms underlying the susceptibility of MNs to cell death remain unclear. Here we report that astrocytes derived from either mice bearing mutations in genes associated with ALS or human subjects with ALS reduce the expression of major histocompatibility complex class I (MHCI) molecules on MNs; reduced MHCI expression makes these MNs susceptible to astrocyte-induced cell death. Increasing MHCI expression on MNs increases survival and motor performance in a mouse model of ALS and protects MNs against astrocyte toxicity. Overexpression of a single MHCI molecule, HLA-F, protects human MNs from ALS astrocyte-mediated toxicity, whereas knockdown of its receptor, the killer cell immunoglobulin-like receptor KIR3DL2, on human astrocytes results in enhanced MN death. Thus, our data indicate that, in ALS, loss of MHCI expression on MNs renders them more vulnerable to astrocyte-mediated toxicity.

  8. EGFR mediates astragaloside IV-induced Nrf2 activation to protect cortical neurons against in vitro ischemia/reperfusion damages

    Energy Technology Data Exchange (ETDEWEB)

    Gu, Da-min [Department of Anesthesiology, Affiliated Yixing People' s Hospital, Jiangsu University, Yixing (China); Lu, Pei-Hua, E-mail: lphty1_1@163.com [Department of Medical Oncology, Wuxi People' s Hospital Affiliated to Nanjing Medical University, Wuxi (China); Zhang, Ke; Wang, Xiang [Department of Anesthesiology, Affiliated Yixing People' s Hospital, Jiangsu University, Yixing (China); Sun, Min [Department of General Surgery, Affiliated Yixing People' s Hospital, Jiangsu University, Yixing (China); Chen, Guo-Qian [Department of Clinical Laboratory, Wuxi People' s Hospital Affiliated to Nanjing Medical University, Wuxi (China); Wang, Qiong, E-mail: WangQiongprof1@126.com [Department of Clinical Laboratory, Wuxi People' s Hospital Affiliated to Nanjing Medical University, Wuxi (China)

    2015-02-13

    In this study, we tested the potential role of astragaloside IV (AS-IV) against oxygen and glucose deprivation/re-oxygenation (OGD/R)-induced damages in murine cortical neurons, and studied the associated signaling mechanisms. AS-IV exerted significant neuroprotective effects against OGD/R by reducing reactive oxygen species (ROS) accumulation, thereby attenuating oxidative stress and neuronal cell death. We found that AS-IV treatment in cortical neurons resulted in NF-E2-related factor 2 (Nrf2) signaling activation, evidenced by Nrf2 Ser-40 phosphorylation, and its nuclear localization, as well as transcription of antioxidant-responsive element (ARE)-regulated genes: heme oxygenase-1 (HO-1), NAD(P)H:quinone oxidoreductase 1 (NQO-1) and sulphiredoxin 1 (SRXN-1). Knockdown of Nrf2 through lentiviral shRNAs prevented AS-IV-induced ARE genes transcription, and abolished its anti-oxidant and neuroprotective activities. Further, we discovered that AS-IV stimulated heparin-binding-epidermal growth factor (HB-EGF) release to trans-activate epidermal growth factor receptor (EGFR) in cortical neurons. Blockage or silencing EGFR prevented Nrf2 activation by AS-IV, thus inhibiting AS-IV-mediated anti-oxidant and neuroprotective activities against OGD/R. In summary, AS-IV protects cortical neurons against OGD/R damages through activating of EGFR-Nrf2 signaling. - Highlights: • Pre-treatment of astragaloside IV (AS-IV) protects murine cortical neurons from OGD/R. • AS-IV activates Nrf2-ARE signaling in murine cortical neurons. • Nrf2 is required for AS-IV-mediated anti-oxidant and neuroprotective activities. • AS-IV stimulates HB-EGF release to trans-activate EGFR in murine cortical neurons. • EGFR mediates AS-IV-induced Nrf2 activation and neuroprotection against OGD/R.

  9. Tamoxifen mediated estrogen receptor activation protects against early impairment of hippocampal neuron excitability in an oxygen/glucose deprivation brain slice ischemia model.

    Science.gov (United States)

    Zhang, Huaqiu; Xie, Minjie; Schools, Gary P; Feustel, Paul F; Wang, Wei; Lei, Ting; Kimelberg, Harold K; Zhou, Min

    2009-01-09

    Pretreatment of ovarectomized rats with estrogen shows long-term protection via activation of the estrogen receptor (ER). However, it remains unknown whether activation of the ER can provide protection against early neuronal damage when given acutely. We simulated ischemic conditions by applying oxygen and glucose deprived (OGD) solution to acute male rat hippocampal slices and examined the neuronal electrophysiological changes. Pyramidal neurons and interneurons showed a time-dependent membrane potential depolarization and reduction in evoked action potential frequency and amplitude over a 10 to 15 min OGD exposure. These changes were largely suppressed by 10 microM TAM. The TAM effect was neuron-specific as the OGD-induced astrocytic membrane potential depolarization was not altered. The TAM effect was mediated through ER activation because it could be simulated by 17beta-estradiol and was completely inhibited by the ER inhibitor ICI 182, 780, and is therefore an example of TAM's selective estrogen receptor modulator (SERM) action. We further show that TAM's effects on OGD-induced impairment of neuronal excitability was largely due to activation of neuroprotective BK channels, as the TAM effect was markedly attenuated by the BK channel inhibitor paxilline at 10 microM. TAM also significantly reduced the frequency and amplitude of AMPA receptor mediated spontaneous excitatory postsynaptic currents (sEPSCs) in pyramidal neurons which is an early consequence of OGD. Altogether, this study demonstrates that both 17beta-estradiol and TAM attenuate neuronal excitability impairment early on in a simulated ischemia model via ER activation mediated potentiation of BK K(+) channels and reduction in enhanced neuronal AMPA/NMDA receptor-mediated excitotoxicity.

  10. Protective effect of tubuloside B on TNFα-induced apoptosis in neuronal cells

    Institute of Scientific and Technical Information of China (English)

    Min DENG; Jin-yuan ZHAO; Xiao-dong JU; Peng-fei TU; Yong JIANG; Zheng-bin LI

    2004-01-01

    AIM: To investigate the neuroprotective effect of tubuloside B, one of the phenylethanoids isolated from the stems of Cistanche salsa, on tumor necrosis factor-alpha (TNFα)-induced apoptosis in SH-SY5Y neuronal cells.METHODS: Cell viability was analyzed using MTT assay. Apoptotic cells were detected using Hoechst33342 staining, and confirmed by DNA fragmentation and flow cytometric analysis. The activity of caspase-3 was measured with special assay kit. The concentration of free intracellular calcium was determined with the probe Indo-1 by spectrometer. The level of intracellular reactive oxygen species and the potential of mitochondrial membrane were determined by laser scanning confocal microscopy (LSCM) combined with fluorescence probe H2DCFDA or JC-1 respectively. RESULTS: SH-SY5Y cells treated with TNFα 100 μg/L for 36 h showed typical morphological changes of apoptosis. DNA ladder could be observed by agarose gel electrophoresis. The highest percentage of apoptotic cells accumulated to 37.5 %. Following 36 h treatment with TNFα, accumulation of intracellular ROS and [Ca2+]i and decrease in mitochondrial membrane potential were observed, and caspase-3 activity increased by about five-fold compared with controls. However, pretreatment with tubuloside B (1, 10, or 100 mg/L) for 2 h attenuated the TNFα-mediated apoptosis. The antiapoptotic action of tubuloside B was partially dependent on an anti-oxidative stress effects, maintain of mitochondria function, decrease of concentration of free intracellular calcium and inhibition of caspase-3 activity. CONCLUSION: Tubuloside B has the neuroprotective capacity to antagonize TNFα-induced apoptosis in SH-SY5Y cells and may be useful in treating some neurodegenerative diseases.

  11. Imidazenil, a non-sedating anticonvulsant benzodiazepine, is more potent than diazepam in protecting against DFP-induced seizures and neuronal damage.

    Science.gov (United States)

    Kadriu, Bashkim; Guidotti, Alessandro; Costa, Erminio; Auta, James

    2009-02-27

    Organophosphate (OP)-nerve agent poisoning may lead to prolonged epileptiform seizure activity, which can result in irreversible neuronal brain damage. A timely and effective control of seizures with pharmacological agents can minimize the secondary and long-term neuropathology that may result from this damage. Diazepam, the current anticonvulsant of choice in the management of OP poisoning, is associated with unwanted effects such as sedation, amnesia, cardio-respiratory depression, anticonvulsant tolerance, and dependence liabilities. In search for an efficacious and safer anticonvulsant benzodiazepine, we studied imidazenil, a potent anticonvulsant that is devoid of sedative action and has a low intrinsic efficacy at alpha1- but is a high efficacy positive allosteric modulator at alpha5-containing GABA(A) receptors. We compared the potency of a combination of 2 mg/kg, i.p. atropine with: (a) imidazenil 0.05-0.5 mg/kg i.p. or (b) equipotent anti-bicuculline doses of diazepam (0.5-5 mg/kg, i.p.), against diisopropyl fluorophosphate (DFP; 1.5 mg/kg, s.c.)-induced status epilepticus and its associated neuronal damage. The severity and frequency of seizure activities were determined by continuous radio telemetry recordings while the extent of neuronal damage and neuronal degeneration were assessed using the TUNEL-based cleaved DNA end-labeling technique or neuron-specific nuclear protein (NeuN)-immunolabeling and Fluoro-Jade B (FJB) staining, respectively. We report here that the combination of atropine and imidazenil is at least 10-fold more potent and longer lasting than the combination with diazepam at protecting rats from DFP-induced seizures and the associated neuronal damage or ongoing degeneration in the anterior cingulate cortex, CA1 hippocampus, and dentate gyrus. While 0.5 mg/kg imidazenil effectively attenuated DFP-induced neuronal damage and the ongoing neuronal degeneration in the anterior cingulate cortex, dentate gyrus, and CA1 hippocampus, 5 mg/kg or

  12. Fractalkine/CX3CL1 protects striatal neurons from synergistic morphine and HIV-1 Tat-induced dendritic losses and death

    Directory of Open Access Journals (Sweden)

    Suzuki Masami

    2011-11-01

    Full Text Available Abstract Background Fractalkine/CX3CL1 and its cognate receptor CX3CR1 are abundantly expressed in the CNS. Fractalkine is an unusual C-X3-C motif chemokine that is important in neuron-microglial communication, a co-receptor for HIV infection, and can be neuroprotective. To assess the effects of fractalkine on opiate-HIV interactive neurotoxicity, wild-type murine striatal neurons were co-cultured with mixed glia from the striata of wild-type or Cx3cr1 knockout mice ± HIV-1 Tat and/or morphine. Time-lapse digital images were continuously recorded at 20 min intervals for up to 72 h using computer-aided microscopy to track the same cells repeatedly. Results Co-exposure to Tat and morphine caused synergistic increases in neuron death, dendritic pruning, and microglial motility as previously reported. Exogenous fractalkine prevented synergistic Tat and morphine-induced dendritic losses and neuron death even though the inflammatory mediator TNF-α remained significantly elevated. Antibody blockade of CX3CR1 mimicked the toxic effects of morphine plus Tat, but did not add to their toxicity; while fractalkine failed to protect wild-type neurons co-cultured with Cx3cr1-/--null glia against morphine and Tat toxicity. Exogenous fractalkine also normalized microglial motility, which is elevated by Tat and morphine co-exposure, presumably limiting microglial surveillance that may lead to toxic effects on neurons. Fractalkine immunofluorescence was expressed in neurons and to a lesser extent by other cell types, whereas CX3CR1 immunoreactivity or GFP fluorescence in cells cultured from the striatum of Cx3cr1-/- (Cx3cr1GFP/GFP mice were associated with microglia. Immunoblotting shows that fractalkine levels were unchanged following Tat and/or morphine exposure and there was no increase in released fractalkine as determined by ELISA. By contrast, CX3CR1 protein levels were markedly downregulated. Conclusions The results suggest that deficits in fractalkine

  13. Topiramate attenuates early brain injury following subarachnoid haemorrhage in rats via duplex protection against inflammation and neuronal cell death.

    Science.gov (United States)

    Tian, Yong; Guo, Song-Xue; Li, Jian-Ru; Du, Hang-Gen; Wang, Chao-Hui; Zhang, Jian-Min; Wu, Qun

    2015-10-05

    Early brain injury (EBI) following aneurysmal subarachnoid haemorrhage (SAH) insults contributes to the poor prognosis and high mortality observed in SAH patients. Topiramate (TPM) is a novel, broad-spectrum, antiepileptic drug with a reported protective effect against several brain injuries. The current study aimed to investigate the potential of TPM for neuroprotection against EBI after SAH and the possible dose-dependency of this effect. An endovascular perforation SAH model was established in rats, and TPM was administered by intraperitoneal injection after surgery at three different doses (20mg/kg, 40mg/kg, and 80mg/kg). The animals' neurological scores and brain water content were evaluated, and ELISA, Western blotting and immunostaining assays were conducted to assess the effect of TPM. The results revealed that TPM lowers the elevated levels of myeloperoxidase and proinflammatory mediators observed after SAH in a dose-related fashion, and the nuclear factor-kappa B (NF-κB) signalling pathway is the target of neuroinflammation regulation. In addition, TPM ameliorated SAH-induced cortical neuronal apoptosis by influencing Bax, Bcl-2 and cleaved caspase-3 protein expression, and the effect of TPM was enhanced in a dose-dependent manner. Various dosages of TPM also upregulated the protein expression of the γ-aminobutyric acid (GABA)-ergic signalling molecules, GABAA receptor (GABAAR) α1, GABAAR γ2, and K(+)-Cl(-) co-transporter 2 (KCC2) together and downregulated Na(+)-K(+)-Cl(-) co-transporter 1 (NKCC1) expression. Thus, TPM may be an effective neuroprotectant in EBI after SAH by regulating neuroinflammation and neuronal cell death.

  14. Alteration of protein folding and degradation in motor neuron diseases : Implications and protective functions of small heat shock proteins

    NARCIS (Netherlands)

    Carra, Serena; Crippa, Valeria; Rusmini, Paola; Boncoraglio, Alessandra; Minoia, Melania; Giorgetti, Elisa; Kampinga, Harm H.; Poletti, Angelo

    2012-01-01

    Motor neuron diseases (MNDs) are neurodegenerative disorders that specifically affect the survival and function of upper and/or lower motor neurons. Since motor neurons are responsible for the control of voluntary muscular movement, MNDs are characterized by muscle spasticity, weakness and atrophy.

  15. Allium cepa Extract and Quercetin Protect Neuronal Cells from Oxidative Stress via PKC-ε Inactivation/ERK1/2 Activation

    Science.gov (United States)

    2016-01-01

    Oxidative stress plays an important role in the pathophysiology of various neurologic disorders. Allium cepa extract (ACE) and their main flavonoid component quercetin (QCT) possess antioxidant activities and protect neurons from oxidative stress. We investigated the underlying molecular mechanisms, particularly those linked to the antioxidant effects of the ACE. Primary cortical neuronal cells derived from mouse embryos were preincubated with ACE or QCT for 30 min and exposed to L-buthionine sulfoximine for 4~24 h. We found that ACE and QCT significantly decreased neuronal death and the ROS increase induced by L-buthionine-S, R-sulfoximine (BSO) in a concentration-dependent manner. Furthermore, ACE and QCT activated extracellular signal-regulated kinase 1/2 (ERK1/2), leading to downregulation of protein kinase C-ε (PKC-ε) in BSO-stimulated neuronal cells. In addition, ACE and QCT decreased the phosphorylated levels of p38 mitogen-activated protein kinase. Our results provide new insight into the protective mechanism of ACE and QCT against oxidative stress in neuronal cells. The results suggest that the inactivation of PKC-ε induced by phosphorylating ERK1/2 is responsible for the neuroprotective effect of ACE and QCT against BSO-induced oxidative stress. PMID:27668036

  16. Vanillin Protects Dopaminergic Neurons against Inflammation-Mediated Cell Death by Inhibiting ERK1/2, P38 and the NF-κB Signaling Pathway

    Science.gov (United States)

    Yan, Xuan; Liu, Dian-Feng; Zhang, Xiang-Yang; Liu, Dong; Xu, Shi-Yao; Chen, Guang-Xin; Huang, Bing-Xu; Ren, Wen-Zhi; Wang, Wei; Fu, Shou-Peng; Liu, Ju-Xiong

    2017-01-01

    Neuroinflammation plays a very important role in the pathogenesis of Parkinson’s disease (PD). After activation, microglia produce pro-inflammatory mediators that damage surrounding neurons. Consequently, the inhibition of microglial activation might represent a new therapeutic approach of PD. Vanillin has been shown to protect dopaminergic neurons, but the mechanism is still unclear. Herein, we further study the underlying mechanisms in lipopolysaccharide (LPS)-induced PD models. In vivo, we firstly established rat models of PD by unilateral injection of LPS into substantia nigra (SN), and then examined the role of vanillin in motor dysfunction, microglial activation and degeneration of dopaminergic neurons. In vitro, murine microglial BV-2 cells were treated with vanillin prior to the incubation of LPS, and then the inflammatory responses and the related signaling pathways were analyzed. The in vivo results showed that vanillin markedly improved the motor dysfunction, suppressed degeneration of dopaminergic neurons and inhibited microglial over-activation induced by LPS intranigral injection. The in vitro studies demonstrated that vanillin reduces LPS-induced expression of inducible nitric oxide (iNOS), cyclooxygenase-2 (COX-2), IL-1β, and IL-6 through regulating ERK1/2, p38 and NF-κB signaling. Collectively, these data indicated that vanillin has a role in protecting dopaminergic neurons via inhibiting inflammatory activation. PMID:28208679

  17. Near infrared radiation protects against oxygen-glucose deprivation-induced neurotoxicity by down-regulating neuronal nitric oxide synthase (nNOS) activity in vitro.

    Science.gov (United States)

    Yu, Zhanyang; Li, Zhaoyu; Liu, Ning; Jizhang, Yunneng; McCarthy, Thomas J; Tedford, Clark E; Lo, Eng H; Wang, Xiaoying

    2015-06-01

    Near infrared radiation (NIR) has been shown to be neuroprotective against neurological diseases including stroke and brain trauma, but the underlying mechanisms remain poorly understood. In the current study we aimed to investigate the hypothesis that NIR may protect neurons by attenuating oxygen-glucose deprivation (OGD)-induced nitric oxide (NO) production and modulating cell survival/death signaling. Primary mouse cortical neurons were subjected to 4 h OGD and NIR was applied at 2 h reoxygenation. OGD significantly increased NO level in primary neurons compared to normal control, which was significantly ameliorated by NIR at 5 and 30 min post-NIR. Neither OGD nor NIR significantly changed neuronal nitric oxide synthase (nNOS) mRNA or total protein levels compared to control groups. However, OGD significantly increased nNOS activity compared to normal control, and this effect was significantly diminished by NIR. Moreover, NIR significantly ameliorated the neuronal death induced by S-Nitroso-N-acetyl-DL-penicillamine (SNAP), a NO donor. Finally, NIR significantly rescued OGD-induced suppression of p-Akt and Bcl-2 expression, and attenuated OGD-induced upregulation of Bax, BAD and caspase-3 activation. These results suggest NIR may protect against OGD at least partially through reducing NO production by down-regulating nNOS activity, and modulating cell survival/death signaling.

  18. Vanillin Protects Dopaminergic Neurons against Inflammation-Mediated Cell Death by Inhibiting ERK1/2, P38 and the NF-κB Signaling Pathway

    Directory of Open Access Journals (Sweden)

    Xuan Yan

    2017-02-01

    Full Text Available Neuroinflammation plays a very important role in the pathogenesis of Parkinson’s disease (PD. After activation, microglia produce pro-inflammatory mediators that damage surrounding neurons. Consequently, the inhibition of microglial activation might represent a new therapeutic approach of PD. Vanillin has been shown to protect dopaminergic neurons, but the mechanism is still unclear. Herein, we further study the underlying mechanisms in lipopolysaccharide (LPS-induced PD models. In vivo, we firstly established rat models of PD by unilateral injection of LPS into substantia nigra (SN, and then examined the role of vanillin in motor dysfunction, microglial activation and degeneration of dopaminergic neurons. In vitro, murine microglial BV-2 cells were treated with vanillin prior to the incubation of LPS, and then the inflammatory responses and the related signaling pathways were analyzed. The in vivo results showed that vanillin markedly improved the motor dysfunction, suppressed degeneration of dopaminergic neurons and inhibited microglial over-activation induced by LPS intranigral injection. The in vitro studies demonstrated that vanillin reduces LPS-induced expression of inducible nitric oxide (iNOS, cyclooxygenase-2 (COX-2, IL-1β, and IL-6 through regulating ERK1/2, p38 and NF-κB signaling. Collectively, these data indicated that vanillin has a role in protecting dopaminergic neurons via inhibiting inflammatory activation.

  19. Vanillin Protects Dopaminergic Neurons against Inflammation-Mediated Cell Death by Inhibiting ERK1/2, P38 and the NF-κB Signaling Pathway.

    Science.gov (United States)

    Yan, Xuan; Liu, Dian-Feng; Zhang, Xiang-Yang; Liu, Dong; Xu, Shi-Yao; Chen, Guang-Xin; Huang, Bing-Xu; Ren, Wen-Zhi; Wang, Wei; Fu, Shou-Peng; Liu, Ju-Xiong

    2017-02-12

    Neuroinflammation plays a very important role in the pathogenesis of Parkinson's disease (PD). After activation, microglia produce pro-inflammatory mediators that damage surrounding neurons. Consequently, the inhibition of microglial activation might represent a new therapeutic approach of PD. Vanillin has been shown to protect dopaminergic neurons, but the mechanism is still unclear. Herein, we further study the underlying mechanisms in lipopolysaccharide (LPS)-induced PD models. In vivo, we firstly established rat models of PD by unilateral injection of LPS into substantia nigra (SN), and then examined the role of vanillin in motor dysfunction, microglial activation and degeneration of dopaminergic neurons. In vitro, murine microglial BV-2 cells were treated with vanillin prior to the incubation of LPS, and then the inflammatory responses and the related signaling pathways were analyzed. The in vivo results showed that vanillin markedly improved the motor dysfunction, suppressed degeneration of dopaminergic neurons and inhibited microglial over-activation induced by LPS intranigral injection. The in vitro studies demonstrated that vanillin reduces LPS-induced expression of inducible nitric oxide (iNOS), cyclooxygenase-2 (COX-2), IL-1β, and IL-6 through regulating ERK1/2, p38 and NF-κB signaling. Collectively, these data indicated that vanillin has a role in protecting dopaminergic neurons via inhibiting inflammatory activation.

  20. Squamosamide derivative FLZ protected dopaminergic neuron by activating Akt signaling pathway in 6-OHDA-induced in vivo and in vitro Parkinson's disease models.

    Science.gov (United States)

    Bao, Xiu-Qi; Kong, Xiang-Chen; Kong, Li-Bing; Wu, Liang-Yu; Sun, Hua; Zhang, Dan

    2014-02-14

    Parkinson's disease (PD) is a neurodegenerative disease affecting up to 80% of dopaminergic neurons in the nigrostriatal pathway. FLZ, a novel synthetic squamosamide derivative from a Chinese herb, has been shown to have neuroprotective effects in experimental PD models. In this study, we carried out a set of in vitro and in vivo experiments to address the neuroprotective effect of FLZ and related mechanism. The results showed that FLZ significantly improved motor dysfunction and dopaminergic neuronal loss of rats injured by 6-hydroxydopamine (6-OHDA). The beneficial effects of FLZ attributed to the elevation of dopaminergic neuron number, dopamine level and tyrosine hydroxylase (TH) activity. Mechanistic study showed that FLZ protected TH activity and dopaminergic neurons through decreasing α-synuclein (α-Syn) expression and the interaction between α-Syn and TH. Further studies indicated the involvement of phosphoinositide 3-kinases (PI3K)/Akt signaling pathway in the protective effect of FLZ since it showed that blocking PI3K/Akt signaling pathway prevented the expression of α-Syn and attenuated the neuroprotection of FLZ. In addition, FLZ treatment reduced the expression of RTP801, an important protein involved in the pathogenesis of PD. Taken together, these results revealed that FLZ suppressed α-Syn expression and elevated TH activity in dopaminergic neuron through activating Akt survival pathway in 6-OHDA-induced PD models. The data also provided evidence that FLZ had potent neuroprotecive effects and might become a new promising agent for PD treatment.

  1. Estradiol and raloxifene protect cultured SN4741 neurons against oxidative stress.

    Science.gov (United States)

    Biewenga, Eric; Cabell, Leigh; Audesirk, Teresa

    2005-01-20

    A large body of research has documented neuroprotective effects of estrogen against oxidative stress. Some neurodegenerative diseases such as Parkinson's disease, in which oxidative stress has been implicated as a contributing factor, affect more males than females, suggesting a possible protective effect of estrogen. We used the clonal substantia nigra cell line SN4741 to compare the neuroprotective properties of estrogen and raloxifene against oxidative stress, and to determine whether raloxifene acted as an estrogen agonist or antagonist in this system. We pretreated SN4741 cultures with alpha-estradiol, beta-estradiol, and raloxifene, and exposed them to hydrogen peroxide. Low nanomolar levels of raloxifene, beta-estradiol, and alpha-estradiol all significantly reduced cell death caused by oxidative stress. The estrogen receptor (ER) antagonist ICI 182,780 failed to reverse the neuroprotection by beta-estradiol, suggesting that the effect is not mediated by a classical ER. Western blotting using an antibody to the C-terminus region of ER-alpha revealed two bands, one at approximately 67 kDa (corresponding to ER-alpha) and a more prominent band at approximately 55-56 kDa. These results suggest that, in this cell line, both raloxifene and estrogen may be acting via a non-classical estrogen receptor.

  2. Astrocytes protect neurons from Aβ1-42 peptide-induced neurotoxicity increasing TFAM and PGC-1 and decreasing PPAR-γ and SIRT-1.

    Science.gov (United States)

    Aguirre-Rueda, Diana; Guerra-Ojeda, Sol; Aldasoro, Martin; Iradi, Antonio; Obrador, Elena; Ortega, Angel; Mauricio, M Dolores; Vila, Jose Ma; Valles, Soraya L

    2015-01-01

    One of the earliest neuropathological events in Alzheimer's disease is accumulation of astrocytes at sites of Aβ1-42 depositions. Our results indicate that Aβ1-42 toxic peptide increases lipid peroxidation, apoptosis and cell death in neurons but not in astrocytes in primary culture. Aβ1-42-induced deleterious neuronal effects are not present when neurons and astrocytes are mixed cultured. Stimulation of astrocytes with toxic Aβ1-42 peptide increased p-65 and decreased IκB resulting in inflammatory process. In astrocytes Aβ1-42 decreases protein expressions of sirtuin 1 (SIRT-1) and peroxisome proliferator-activated receptor γ (PPAR-γ) and over-expresses peroxisome proliferator-activated receptor γ coactivator 1 (PGC-1) and mitochondrial transcription factor A (TFAM), protecting mitochondria against Aβ1-42-induced damage and promoting mitochondrial biogenesis. In summary our data suggest that astrocytes may have a key role in protecting neurons, increasing neural viability and mitochondrial biogenesis, acquiring better oxidative stress protection and perhaps modulating inflammatory processes against Aβ1-42 toxic peptide. This might be a sign of a complex epigenetic process in Alzheimer's disease development.

  3. Astrocytes require insulin-like growth factor I to protect neurons against oxidative injury [v1; ref status: indexed, http://f1000r.es/2lf

    Directory of Open Access Journals (Sweden)

    Laura Genis

    2014-01-01

    Full Text Available Oxidative stress is a proposed mechanism in brain aging, making the study of its regulatory processes an important aspect of current neurobiological research. In this regard, the role of the aging regulator insulin-like growth factor I (IGF-I in brain responses to oxidative stress remains elusive as both beneficial and detrimental actions have been ascribed to this growth factor. Because astrocytes protect neurons against oxidative injury, we explored whether IGF-I participates in astrocyte neuroprotection and found that blockade of the IGF-I receptor in astrocytes abrogated their rescuing effect on neurons. The protection mediated by IGF-I against oxidative stress (H2O2 in astrocytes is probably needed for these cells to provide adequate neuroprotection. Indeed, in astrocytes but not in neurons, IGF-I helps decrease the pro-oxidant protein thioredoxin-interacting protein 1 and normalizes the levels of reactive oxygen species. Furthermore, IGF-I cooperates with trophic signals produced by astrocytes in response to H2O2 such as stem cell factor (SCF to protect neurons against oxidative insult. After stroke, a condition associated with brain aging where oxidative injury affects peri-infarcted regions, a simultaneous increase in SCF and IGF-I expression was found in the cortex, suggesting that a similar cooperative response takes place in vivo. Cell-specific modulation by IGF-I of brain responses to oxidative stress may contribute in clarifying the role of IGF-I in brain aging.

  4. Astrocytes require insulin-like growth factor I to protect neurons against oxidative injury [v2; ref status: indexed, http://f1000r.es/38u

    Directory of Open Access Journals (Sweden)

    Laura Genis

    2014-04-01

    Full Text Available Oxidative stress is a proposed mechanism in brain aging, making the study of its regulatory processes an important aspect of current neurobiological research. In this regard, the role of the aging regulator insulin-like growth factor I (IGF-I in brain responses to oxidative stress remains elusive as both beneficial and detrimental actions have been ascribed to this growth factor. Because astrocytes protect neurons against oxidative injury, we explored whether IGF-I participates in astrocyte neuroprotection and found that blockade of the IGF-I receptor in astrocytes abrogated their rescuing effect on neurons. We found that IGF-I directly protects astrocytes against oxidative stress (H2O2. Indeed, in astrocytes but not in neurons, IGF-I decreases the pro-oxidant protein thioredoxin-interacting protein 1 and normalizes the levels of reactive oxygen species. Furthermore, IGF-I cooperates with trophic signals produced by astrocytes in response to H2O2 such as stem cell factor (SCF to protect neurons against oxidative insult. After stroke, a condition associated with brain aging where oxidative injury affects peri-infarcted regions, a simultaneous increase in SCF and IGF-I expression was found in the cortex, suggesting that a similar cooperative response takes place in vivo. Cell-specific modulation by IGF-I of brain responses to oxidative stress may contribute in clarifying the role of IGF-I in brain aging.

  5. Inhibition of Autophagy via Activation of PI3K/Akt Pathway Contributes to the Protection of Ginsenoside Rb1 against Neuronal Death Caused by Ischemic Insults

    Directory of Open Access Journals (Sweden)

    Tianfei Luo

    2014-09-01

    Full Text Available Lethal autophagy is a pathway leading to neuronal death caused by transient global ischemia. In this study, we examined the effect of Ginsenoside Rb1 (GRb1 on ischemia/reperfusion-induced autophagic neuronal death and investigated the role of PI3K/Akt. Ischemic neuronal death in vitro was induced by using oxygen glucose deprivation (OGD in SH-SY5Y cells, and transient global ischemia was produced by using two vessels occlusion in rats. Cellular viability of SH-SY5Y cells was assessed by MTT assay, and CA1 neuronal death was evaluated by Hematoxylin-eosin staining. Autophagic vacuoles were detected by using both fluorescent microscopy in combination with acridine orange (AO and Monodansylcadaverine (MDC staining and transmission electronic microscopy. Protein levels of LC3II, Beclin1, total Akt and phosphor-Akt at Ser473 were examined by western blotting analysis. GRb1 inhibited both OGD and transient ischemia-induced neuronal death and mitigated OGD-induced autophagic vacuoles in SH-SY5Y cells. By contrast, PI3K inhibitor LY294002 counteracted the protection of GRb1 against neuronal death caused by either OGD or transient ischemia. LY294002 not only mitigated the up-regulated protein level of phosphor Akt at Ser473 caused by GRb1, but also reversed the inhibitory effect of GRb1 on OGD and transient ischemia-induced elevation in protein levels of LC3II and Beclin1.

  6. Complement factor H, a marker of self protects against experimental autoimmune encephalomyelitis.

    Science.gov (United States)

    Griffiths, Mark R; Neal, Jim W; Fontaine, Marc; Das, Trina; Gasque, Philippe

    2009-04-01

    The CNS innate immune response is a "double-edged sword" representing a fine balance between protective antipathogen responses and detrimental neurocytotoxic effects. Hence, it is important to identify the key regulatory mechanisms involved in the control of CNS innate immunity and which could be harnessed to explore novel therapeutic avenues. In analogy to the newly described neuroimmune regulatory proteins also known as "don't eat me" signals (CD200, CD47, CD22, fractalkine, semaphorins), we herein identify the key role of complement regulator factor H (fH) in controlling neuroinflammation initiated in an acute mouse model of Ab-dependent experimental autoimmune encephalomyelitis. Mouse fH was found to be abundantly expressed by primary cultured neurons and neuronal cell lines (N1E115 and Neuro2a) at a level comparable to BV2 microglia and CLTT astrocytes. Mouse neurons expressed other complement regulators crry and low levels of CD55. In the brain, the expression of fH was localized to neuronal bodies and axons, endothelial cells, microglia but not oligodendrocytes and myelin sheaths and was dramatically reduced in inflammatory experimental autoimmune encephalomyelitis settings. When exogenous human fH was administered to disease Ab-dependent experimental autoimmune encephalomyelitis animals, there was a significant decrease in clinical score, inflammation, and demyelination, as compared with PBS-injected animals. We found that the accumulation of human fH in the brain parenchyma protected neurons from complement opsonization, axonal injury, and leukocyte infiltration. Our data argue for a key regulatory activity of fH in neuroprotection and provide novel therapeutic avenues for CNS chronic inflammatory diseases.

  7. Protective effects of N-methyl-D-aspartate receptor antagonism on VX-induced neuronal cell death in cultured rat cortical neurons.

    Science.gov (United States)

    Wang, Yushan; Weiss, M Tracy; Yin, Junfei; Tenn, Catherine C; Nelson, Peggy D; Mikler, John R

    2008-01-01

    Exposure of the central nervous system to organophosphorus (OP) nerve agents induces seizures and neuronal cell death. Here we report that the OP nerve agent, VX, induces apoptotic-like cell death in cultured rat cortical neurons. The VX effects on neurons were concentration-dependent, with an IC(50) of approximately 30 microM. Blockade of N-methyl-D-aspartate receptors (NMDAR) with 50 microM. D-2-amino-5-phosphonovalerate (APV) diminished 30 microM VX-induced total cell death, as assessed by alamarBlue assay and Hoechst staining. In contrast, neither antagonists of alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid receptors (AMPARs) nor metabotropic glutamate receptors (mGluRs) had any effect on VX-induced neurotoxicity. VX-induced neuronal cell death could not be solely attributed to acetylcholinesterase (AChE) inhibition, since neither the reversible pharmacological cholinesterase inhibitor, physostigmine, nor the muscarinic receptor antagonist, atropine, affected VX-induced cell death. Importantly, APV was found to be therapeutically effective against VX-induced cell death up to 2 h post VX exposure. These results suggest that NMDARs, but not AMPARs or mGluRs, play important roles in VX-induced cell death in cultured rat cortical neurons. Based on their therapeutic effects, NMDAR antagonists may be beneficial in the treatment of VX-induced neurotoxicities.

  8. Protective effects of bupivacaine against kainic acid-induced seizure and neuronal cell death in the rat hippocampus.

    Science.gov (United States)

    Chiu, Kuan Ming; Wu, Chia Chan; Wang, Ming Jiuh; Lee, Ming Yi; Wang, Su Jane

    2015-01-01

    The excessive release of glutamate is a critical element in the neuropathology of epilepsy, and bupivacaine, a local anesthetic agent, has been shown to inhibit the release of glutamate in rat cerebrocortical nerve terminals. This study investigated whether bupivacaine produces antiseizure and antiexcitotoxic effects using a kainic acid (KA) rat model, an animal model used for temporal lobe epilepsy, and excitotoxic neurodegeneration experiments. The results showed that administering bupivacaine (0.4 mg/kg or 2 mg/kg) intraperitoneally to rats 30 min before intraperitoneal injection of KA (15 mg/kg) increased seizure latency and reduced the seizure score. In addition, bupivacaine attenuated KA-induced hippocampal neuronal cell death, and this protective effect was accompanied by the inhibition of microglial activation and production of proinflammatory cytokines such as interleukin (IL)-1β, IL-6, and tumor necrosis factor-α in the hippocampus. Moreover, bupivacaine shortened the latency of escaping onto the platform in the Morris water maze learning performance test. Collectively, these data suggest that bupivacaine has therapeutic potential for treating epilepsy.

  9. Protective Effect of Isoflurane and Sevoflurane on Ischemic Neurons and Expression of Bcl-2 and ICE Genes in Rat Brain

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    To study the protective effect of volatile anesthetics, isoflurane and sevoflurane, on ischemic neurons after cerebral ischemia-reperfusion in rats and its possible molecular mechanism. Methods Rat cerebral ischemia-reperfusion model was developed by occlusion of the middle cerebral artery (MCA) and bilateral common carotid arteries (CCAs) 1 h after reperfusion. Using flow cytometry (FCM) and Northern blot hybridization, we calculated the number of apoptotic bodies and detected the expression of bcl-2 mRNA and interleukin-1 β converting enzyme (ICE) mRNA. Results The apoptotic bodies in hippocampus analyzed by FCM peaked at appeared 24 h after reperfusion, and decreased about 54% and 40%, respectively,after treatment with isoflurane and sevoflurane, as compared with ischemic group. There was no significant difference in the expression of bcl-2 mRNA and ICE mRNA between the inhaled anesthetic groups and ischemic group in hippocampus 24 hafter MCA/CCAs occlusion. Conclusion Isoflurane and sevoflurane partially inhibit apoptosis but have no significant effect on the expression of bcl-2 and ICE genes.

  10. Pretreatment with scutellaria baicalensis stem-leaf total lfavonoid protects against cerebral ischemia/reperfusion injur y in hippocampal neurons

    Institute of Scientific and Technical Information of China (English)

    Xiangyu Kong; Wei Kong; Guangxin Miao; Shumin Zhao; Meng Chen; Xiaoying Zheng; Jiangtao Bai

    2014-01-01

    Previous experimental studies have shown that cerebral infarction can be effectively reduced following treatment with scutellaria baicalensis stem-leaf total lfavonoid (SSTF). However, the mechanism of action of SSTF as a preventive drug to treat cerebral infarction remains unclear. In this study, Sprague-Dawley rats were pretreated with 50, 100, 200 mg/kg SSTF via intragastric ad-ministration for 1 week prior to the establishment of focal cerebral ischemia/reperfusion injury. The results showed that pretreatment with SSTF effectively improved neurological function, re-duced brain water content and the permeability of blood vessels, ameliorated ischemia-induced morphology changes in hippocampal microvessels, down-regulated Fas and FasL protein expres-sion, elevated the activity of superoxide dismutase and glutathione peroxidase, and decreased malondialdehyde content. In contrast to low-dose SSTF pretreatment, the above changes were most obvious after pretreatment with moderate-and high-doses of SSTF. Experimental ifndings indicate that SSTF pretreatment can exert protective effects on the brain against cerebral isch-emia/reperfusion injury. The underlying mechanisms may involve reducing brain water content, increasing microvascular recanalization, inhibiting the apoptosis of hippocampal neurons, and attenuating free radical damage.

  11. Protective effects of quercetin on dieldrin-induced endoplasmic reticulum stress and apoptosis in dopaminergic neuronal cells.

    Science.gov (United States)

    Park, Euteum; Chun, Hong Sung

    2016-10-19

    Dieldrin, an organochlorine pesticide still used in several developing countries, has been proposed as a risk factor for Parkinson's disease. Quercetin is one of the potent bioactive flavonoids present in numerous plants. In this study, we investigated the protective effects of quercetin on neurotoxicity induced by dieldrin in cultured dopaminergic SN4741 cells. Our initial experiments showed that quercetin (10-40 μM) dose dependently prevented dieldrin (20 μM)-induced cytotoxicity in SN4741 cells. Pretreatment for 1 h with quercetin before dieldrin application could significantly suppress dieldrin-induced apoptotic characteristics, including nuclear condensation, DNA fragmentation, and caspase-3/7 activation. Results showed that dieldrin-induced markers of endoplasmic reticulum (ER) stress response such as chaperone GRP78, heme oxygenase-1, and phosphorylation of the α subunit of eukaryotic initiation factor 2. In addition, dieldrin reduced antiapoptotic Bcl-2 expression, but significantly elevated a proapoptotic transcription factor CHOP. Furthermore, RNA interference to CHOP almost completely repressed dieldrin-induced apoptotic cell death. Interestingly, quercetin prevented the changes in dieldrin-induced ER stress markers. These results suggest that quercetin may suppress the ER stress-CHOP pathway and dieldrin-induced apoptosis in dopaminergic neurons.

  12. Active components from Siberian ginseng (Eleutherococcus senticosus) for protection of amyloid β(25-35)-induced neuritic atrophy in cultured rat cortical neurons.

    Science.gov (United States)

    Bai, Yanjing; Tohda, Chihiro; Zhu, Shu; Hattori, Masao; Komatsu, Katsuko

    2011-07-01

    Not only neuronal death but also neuritic atrophy and synaptic loss underlie the pathogenesis of Alzheimer's disease as direct causes of the memory deficit. Extracts of Siberian ginseng (the rhizome of Eleutherococcus senticosus) were shown to have protective effects on the regeneration of neurites and the reconstruction of synapses in rat cultured cortical neurons damaged by amyloid β (Aβ)(25-35), and eleutheroside B was one of the active constituents. In this study, a comprehensive evaluation of constituents was conducted to explore active components from Siberian ginseng which can protect against neuritic atrophy induced by Aβ(25-35) in cultured rat cortical neurons. The ethyl acetate, n-butanol and water fractions from the methanol extract of Siberian ginseng showed protective effects against Aβ-induced neuritic atrophy. Twelve compounds were isolated from the active fractions and identified. Among them, eleutheroside B, eleutheroside E and isofraxidin showed obvious protective effects against Aβ(25-35)-induced atrophies of axons and dendrites at 1 and 10 μM.

  13. Neuronal deletion of caspase 8 protects against brain injury in mouse models of controlled cortical impact and kainic acid-induced excitotoxicity.

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    Maryla Krajewska

    Full Text Available Acute brain injury is an important health problem. Given the critical position of caspase 8 at the crossroads of cell death pathways, we generated a new viable mouse line (Ncasp8(-/-, in which the gene encoding caspase 8 was selectively deleted in neurons by cre-lox system.Caspase 8 deletion reduced rates of neuronal cell death in primary neuronal cultures and in whole brain organotypic coronal slice cultures prepared from 4 and 8 month old mice and cultivated up to 14 days in vitro. Treatments of cultures with recombinant murine TNFα (100 ng/ml or TRAIL (250 ng/mL plus cyclohexamide significantly protected neurons against cell death induced by these apoptosis-inducing ligands. A protective role of caspase 8 deletion in vivo was also demonstrated using a controlled cortical impact (CCI model of traumatic brain injury (TBI and seizure-induced brain injury caused by kainic acid (KA. Morphometric analyses were performed using digital imaging in conjunction with image analysis algorithms. By employing virtual images of hundreds of brain sections, we were able to perform quantitative morphometry of histological and immunohistochemical staining data in an unbiased manner. In the TBI model, homozygous deletion of caspase 8 resulted in reduced lesion volumes, improved post-injury motor performance, superior learning and memory retention, decreased apoptosis, diminished proteolytic processing of caspases and caspase substrates, and less neuronal degeneration, compared to wild type, homozygous cre, and caspase 8-floxed control mice. In the KA model, Ncasp8(-/- mice demonstrated superior survival, reduced seizure severity, less apoptosis, and reduced caspase 3 processing. Uninjured aged knockout mice showed improved learning and memory, implicating a possible role for caspase 8 in cognitive decline with aging.Neuron-specific deletion of caspase 8 reduces brain damage and improves post-traumatic functional outcomes, suggesting an important role for this

  14. p53 participates in the protective effects of ischemic post-conditioning against OGD-reperfusion injury in primary cultured spinal cord neurons.

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    Li, Jinquan; Chen, Gong; Gao, Xinjie; Shen, Chao; Zhou, Ping; Wu, Xing; Che, Xiaoming; Xie, Rong

    2017-01-18

    Spinal cord ischemia-reperfusion (I/R) injury is a severe clinical condition, while the mechanism is still not clarified and the therapeutic approach is limited. Ischemia post-conditioning (PC) has been found to have the protective effects against I/R injury in brain. Recently p53 has been reported to take part in the regulation and protection of I/R injury. We hypothesize that PC has the protective effects in primary cultured spinal cord neurons against ischemia-reperfusion injury, and MDM2-p53 signaling pathway may involve in its protective mechanism. In this study, we used an OGD (oxygen and glucose deprivation)-reperfusion model in primary cultured spinal cord neurons to simulate the I/R injury of spinal cord in vitro, and PC was conducted by 3 cycles of 15min restoration of glucose and oxygen with 15min OGD, followed by 6h fully restoration as reperfusion. Lentiviral vectors were used to knock down MDM2 or over-express p53 genes in primary cultured spinal cord neurons. The results showed that 3 cycles of 15min PC generated the most significant protective effects in primary cultured spinal cord neurons against OGD-reperfusion injury. The levels of MDM2 were decreased while p53, Bax, and cleaved Caspase 3 were increased under OGD-reperfusion condition. PC could significantly reverse the down-regulation of MDM2 and up-regulation of p53, Bax, and cleaved Caspase 3 by OGD-reperfusion injury. Moreover, MDM2 knockdown or p53 over-expression could induce the cleaved Caspase 3 expression and blocked the protective effects of PC in primary cultured spinal cord neurons against OGD-reperfusion injury. In conclusion, our work demonstrated that MDM2-p53 pathway plays a pivotal role in the protective effect of PC against OGD-reperfusion injury and PC may be a feasible therapy strategy in the treatment for spinal cord I/R injury.

  15. The Protective Effect of Icariin on Mitochondrial Transport and Distribution in Primary Hippocampal Neurons from 3× Tg-AD Mice.

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    Chen, Yijing; Han, Shuangxue; Huang, Xiuxian; Ni, Jiazuan; He, Xiaoyang

    2016-01-27

    Icariin, a pharmacologically active component isolated from the Chinese herb Epimedium, has been shown to improve spatial learning and memory abilities in Alzheimer's disease (AD) rats through inhibition of Aβ production and tau protein hyperphosphorylation. However, the potential mechanism of icariin-induced protective effects against mitochondrial dysfunctions in AD still remains unclear. In the present study, we investigated the effect of icariin on the modulation of mitochondrial transport and distribution in primary hippocampal cultures from triple-transgenic (3× Tg) AD mice. The results showed that icariin enhanced mitochondrial motility and increased mitochondrial index and mitochondrial length and size in the diseased neurons. Additionally, the expression of the key mitochondrial enzyme, pyruvate dehydrogenase-E1α (PDHE1α), and the post synaptic density protein 95 (PSD95), was preserved in AD neurons after icariin treatment, accompanied by a downregulation of Aβ and phosphorylated tau expression in the corresponding areas. Further study showed that icariin treatment resulted in a decrease in mitochondrial fission protein dynamin-related protein 1 (Drp1) and an increase in fusion protein Mitofusin 2 (Mfn2). These data indicate that icariin can promote mitochondrial transport, protect mitochondria against fragmentation and preserve the expression of mitochondrial and synaptic functional proteins in AD neurons. Thus, icariin may be a potential therapeutic complement for AD and other mitochondrial malfunction-related neuronal degenerative diseases.

  16. The Protective Effect of Icariin on Mitochondrial Transport and Distribution in Primary Hippocampal Neurons from 3× Tg-AD Mice

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    Yijing Chen

    2016-01-01

    Full Text Available Icariin, a pharmacologically active component isolated from the Chinese herb Epimedium, has been shown to improve spatial learning and memory abilities in Alzheimer’s disease (AD rats through inhibition of Aβ production and tau protein hyperphosphorylation. However, the potential mechanism of icariin-induced protective effects against mitochondrial dysfunctions in AD still remains unclear. In the present study, we investigated the effect of icariin on the modulation of mitochondrial transport and distribution in primary hippocampal cultures from triple-transgenic (3× Tg AD mice. The results showed that icariin enhanced mitochondrial motility and increased mitochondrial index and mitochondrial length and size in the diseased neurons. Additionally, the expression of the key mitochondrial enzyme, pyruvate dehydrogenase-E1α (PDHE1α, and the post synaptic density protein 95 (PSD95, was preserved in AD neurons after icariin treatment, accompanied by a downregulation of Aβ and phosphorylated tau expression in the corresponding areas. Further study showed that icariin treatment resulted in a decrease in mitochondrial fission protein dynamin-related protein 1 (Drp1 and an increase in fusion protein Mitofusin 2 (Mfn2. These data indicate that icariin can promote mitochondrial transport, protect mitochondria against fragmentation and preserve the expression of mitochondrial and synaptic functional proteins in AD neurons. Thus, icariin may be a potential therapeutic complement for AD and other mitochondrial malfunction-related neuronal degenerative diseases.

  17. Linoleic acid derivative DCP-LA protects neurons from oxidative stress-induced apoptosis by inhibiting caspase-3/-9 activation.

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    Yaguchi, Takahiro; Fujikawa, Hirokazu; Nishizaki, Tomoyuki

    2010-05-01

    The present study aimed at understanding the effect of the linoleic acid derivative 8-[2-(2-pentyl-cyclopropylmethyl)-cyclopropyl]-octanoic acid (DCP-LA) on oxidative stress-induced neuronal death. Sodium nitroprusside (SNP; 1 mM) reduced viability of cultured rat cerebral cortical neurons to 50% of basal levels, but DCP-LA significantly prevented the SNP effect in a concentration (1-100 nM)-dependent manner. In addition, DCP-LA (100 nM) rescued neurons from SNP-induced degradation. SNP (1 mM) activated caspase-3 and -9 in cultured rat cerebral cortical neurons, but DCP-LA (100 nM) abolished the caspase activation. For a mouse model of middle cerebral artery occlusion, oral administration with DCP-LA (1 mg/kg) significantly diminished degraded area due to cerebral infarction. The results of the present study, thus, demonstrate that DCP-LA protects neurons at least in part from oxidative stress-induced apoptosis by inhibiting activation of caspase-3/-9.

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

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    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.

  19. GDNF secreting human neural progenitor cells protect dying motor neurons, but not their projection to muscle, in a rat model of familial ALS.

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    Masatoshi Suzuki

    Full Text Available BACKGROUND: Amyotrophic lateral sclerosis (ALS is a fatal, progressive neurodegenerative disease characterized by rapid loss of muscle control and eventual paralysis due to the death of large motor neurons in the brain and spinal cord. Growth factors such as glial cell line derived neurotrophic factor (GDNF are known to protect motor neurons from damage in a range of models. However, penetrance through the blood brain barrier and delivery to the spinal cord remains a serious challenge. Although there may be a primary dysfunction in the motor neuron itself, there is also increasing evidence that excitotoxicity due to glial dysfunction plays a crucial role in disease progression. Clearly it would be of great interest if wild type glial cells could ameliorate motor neuron loss in these models, perhaps in combination with the release of growth factors such as GDNF. METHODOLOGY/PRINCIPAL FINDINGS: Human neural progenitor cells can be expanded in culture for long periods and survive transplantation into the adult rodent central nervous system, in some cases making large numbers of GFAP positive astrocytes. They can also be genetically modified to release GDNF (hNPC(GDNF and thus act as long-term 'mini pumps' in specific regions of the rodent and primate brain. In the current study we genetically modified human neural stem cells to release GDNF and transplanted them into the spinal cord of rats over-expressing mutant SOD1 (SOD1(G93A. Following unilateral transplantation into the spinal cord of SOD1(G93A rats there was robust cellular migration into degenerating areas, efficient delivery of GDNF and remarkable preservation of motor neurons at early and end stages of the disease within chimeric regions. The progenitors retained immature markers, and those not secreting GDNF had no effect on motor neuron survival. Interestingly, this robust motor neuron survival was not accompanied by continued innervation of muscle end plates and thus resulted in no

  20. Protection of hypoglycemia-induced neuronal death by β-hydroxybutyrate involves the preservation of energy levels and decreased production of reactive oxygen species.

    Science.gov (United States)

    Julio-Amilpas, Alberto; Montiel, Teresa; Soto-Tinoco, Eva; Gerónimo-Olvera, Cristian; Massieu, Lourdes

    2015-05-01

    Glucose is the main energy substrate in brain but in certain circumstances such as prolonged fasting and the suckling period alternative substrates can be used such as the ketone bodies (KB), beta-hydroxybutyrate (BHB), and acetoacetate. It has been shown that KB prevent neuronal death induced during energy limiting conditions and excitotoxicity. The protective effect of KB has been mainly attributed to the improvement of mitochondrial function. In the present study, we have investigated the protective effect of D-BHB against neuronal death induced by severe noncoma hypoglycemia in the rat in vivo and by glucose deprivation (GD) in cortical cultures. Results show that systemic administration of D-BHB reduces reactive oxygen species (ROS) production in distinct cortical areas and subregions of the hippocampus and efficiently prevents neuronal death in the cortex of hypoglycemic animals. In vitro results show that D-BHB stimulates ATP production and reduces ROS levels, while the nonphysiologic isomer of BHB, L-BHB, has no effect on energy production but reduces ROS levels. Data suggest that protection by BHB, not only results from its metabolic action but is also related to its capability to reduce ROS, rendering this KB as a suitable candidate for the treatment of ischemic and traumatic injury.

  1. cAMP对缺血神经元保护作用的机制研究%Mechanism of cAMP in Ischemic Neuron Protection

    Institute of Scientific and Technical Information of China (English)

    乌日罕; 赵延欣; 刘学源

    2013-01-01

    Current researches and trials witness the lack of effective treatment in neuron protection after stroke. Yet phosphodiesterase inhibitors present protective effect in ischemic neuron in an intracellular cAMP enhancing pattern. The protective mechanism of cAMP in ischemic neuron after stroke was discussed. And the evidences for therapeutic utilization of phosphodiesterase inhibitors were offered.%目前对于缺血性脑卒中后神经元的保护仍缺乏明确有效的药物治疗.磷酸二酯酶抑制剂可通过增加细胞内cAMP的含量对缺血性神经元发挥保护作用.本文从cAMP对缺血性神经元胞内和胞外的作用,阐述cAMP对缺血神经元发挥保护作用的机制,并试图为磷酸二酯酶抑制剂等cAMP增效药物的临床应用提供理论基础.

  2. Salvianolic acid B attenuates toxin-induced neuronal damage via Nrf2-dependent glial cells-mediated protective activity in Parkinson's disease models.

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    Jie Zhou

    Full Text Available Salvianolic acid B (SalB, a bioactive compound isolated from the plant-derived medicinal herb Danshen, has been shown to exert various anti-oxidative and anti-inflammatory activities in several neurological disorders. In this study, we sought to investigate the potential protective effects and associated molecular mechanisms of SalB in Parkinson's disease (PD models. To determine the neuroprotective effects of SalB in vitro, MPP+- or lipopolysaccharide (LPS-induced neuronal injury was achieved using primary cultures with different compositions of neurons, microglia and astrocytes. Our results showed that SalB reduced both LPS- and MPP+-induced toxicity of dopamine neurons in a dose-dependent manner. Additionally, SalB treatment inhibited the release of microglial pro-inflammatory cytokines and resulted in an increase in the expression and release of glial cell line-derived neurotrophic factor (GDNF from astrocytes. Western blot analysis illustrated that SalB increased the expression and nuclear translocation of nuclear factor (erythroid-derived 2-like 2 (Nrf2. The knockdown of Nrf2 using specific small interfering RNA (siRNA partially reversed the SalB-induced GDNF expression and anti-inflammatory activity. Moreover, SalB treatment significantly attenuated dopaminergic (DA neuronal loss, inhibited neuroinflammation, increased GDNF expression and improved the neurological function in MPTP-treated mice. Collectively, these findings demonstrated that SalB protects DA neurons by an Nrf-2 -mediated dual action: reducing microglia activation-mediated neuroinflammation and inducing astrocyte activation-dependent GDNF expression. Importantly the present study also highlights critical roles of glial cells as targets for developing new strategies to alter the progression of neurodegenerative disorders.

  3. Salvianolic Acid B Attenuates Toxin-Induced Neuronal Damage via Nrf2-Dependent Glial Cells-Mediated Protective Activity in Parkinson’s Disease Models

    Science.gov (United States)

    Li, Zhi-Yun; Wei-Ji; Liu, Qi; Ma, Yi-Hui; He, Jiao-Jiang

    2014-01-01

    Salvianolic acid B (SalB), a bioactive compound isolated from the plant-derived medicinal herb Danshen, has been shown to exert various anti-oxidative and anti-inflammatory activities in several neurological disorders. In this study, we sought to investigate the potential protective effects and associated molecular mechanisms of SalB in Parkinson’s disease (PD) models. To determine the neuroprotective effects of SalB in vitro, MPP+- or lipopolysaccharide (LPS)-induced neuronal injury was achieved using primary cultures with different compositions of neurons, microglia and astrocytes. Our results showed that SalB reduced both LPS- and MPP+-induced toxicity of dopamine neurons in a dose-dependent manner. Additionally, SalB treatment inhibited the release of microglial pro-inflammatory cytokines and resulted in an increase in the expression and release of glial cell line-derived neurotrophic factor (GDNF) from astrocytes. Western blot analysis illustrated that SalB increased the expression and nuclear translocation of nuclear factor (erythroid-derived 2)-like 2 (Nrf2). The knockdown of Nrf2 using specific small interfering RNA (siRNA) partially reversed the SalB-induced GDNF expression and anti-inflammatory activity. Moreover, SalB treatment significantly attenuated dopaminergic (DA) neuronal loss, inhibited neuroinflammation, increased GDNF expression and improved the neurological function in MPTP-treated mice. Collectively, these findings demonstrated that SalB protects DA neurons by an Nrf-2 -mediated dual action: reducing microglia activation-mediated neuroinflammation and inducing astrocyte activation-dependent GDNF expression. Importantly the present study also highlights critical roles of glial cells as targets for developing new strategies to alter the progression of neurodegenerative disorders. PMID:24991814

  4. Protective effect of keishi-bukuryo-gan and its constituent medicinal plants against nitric oxide donor-induced neuronal death in cultured cerebellar granule cells.

    Science.gov (United States)

    Shimada, Y; Yokoyama, K; Goto, H; Sekiya, N; Mantani, N; Tahara, E; Hikiami, H; Terasawa, K

    2004-07-01

    Keishi-bukuryo-gan (Gui-Zhi-Fu-Ling-Wan) (KBG) is a traditional Chinese/Japanese medical (Kampo) formulation that has been administered to patients with "Oketsu" (blood stagnation) syndrome. In the process of neuronal cell death induced by brain ischemia, excessive generation of nitric oxide (NO) free radicals is implicated in the neurotoxicity. In the present study, we examined the protective effects of KBG and its constituent medicinal plants against NO donors, sodium nitroprusside (SNP) and 2,2'-(hydroxynitrosohydrazino)bis-ethanamine (NOC18)-induced neuronal death in cultured rat cerebellar granule cells (CGCs). MTT assay showed cell viability to be significantly increased by the addition of KBG extract (KBGE) (100 microg/ml), Cinnamomi Cortex extract (CCE) (3, 10 and 30 microg/ml), Paeoniae Radix extract (PRE) (100 microg/ml) and Moutan Cortex extract (MCE) (10 and 30 microg/ml) compared with exposure to SNP (30 microM, 24 h) only. Also, cell viability was significantly increased by the addition of KBGE (100 and 300 microg/ml), CCE (30 and 100 microg/ml), PRE (100 and 300 microg/ml) and MCE (30 and 100 microg/ml) compared with exposure to NOC 18 (100 microM, 48 h) only. Persicae Semen extract and Hoelen extract did not protect against NO donor-induced neuronal death. These results suggest that KBG has protective effect against NO-mediated neuronal death in cultured CGCs and that it is derived from Cinnamomi Cortex, Paeoniae Radix and Moutan Cortex.

  5. Deletion of protein tyrosine phosphatase 1b in proopiomelanocortin neurons reduces neurogenic control of blood pressure and protects mice from leptin- and sympatho-mediated hypertension.

    Science.gov (United States)

    Bruder-Nascimento, Thiago; Butler, Benjamin R; Herren, David J; Brands, Michael W; Bence, Kendra K; Belin de Chantemèle, Eric J

    2015-12-01

    Protein tyrosine phosphatase 1b (Ptp1b), which represses leptin signaling, is a promising therapeutic target for obesity. Genome wide deletion of Ptp1b, increases leptin sensitivity, protects mice from obesity and diabetes, but alters cardiovascular function by increasing blood pressure (BP). Leptin-control of metabolism is centrally mediated and involves proopiomelanocortin (POMC) neurons. Whether these neurons contribute to leptin-mediated increases in BP remain unclear. We hypothesized that increasing leptin signaling in POMC neurons with Ptp1b deletion will sensitize the cardiovascular system to leptin and enhance neurogenic control of BP. We analyzed the cardiovascular phenotype of Ptp1b+/+ and POMC-Ptp1b-/- mice, at baseline and after 7 days of leptin infusion or sympatho-activation with phenylephrine. POMCPtp1b deletion did not alter baseline cardiovascular hemodynamics (BP, heart rate) but reduced BP response to ganglionic blockade and plasma catecholamine levels that suggests a decreased neurogenic control of BP. In contrast, POMC-Ptp1b deletion increased vascular adrenergic reactivity and aortic α-adrenergic receptors expression. Chronic leptin treatment reduced vascular adrenergic reactivity and blunted diastolic and mean BP increases in POMC-Ptp1b-/- mice only. Similarly POMC-Ptp1b-/- mice exhibited a blunted increased in diastolic and mean BP accompanied by a gradual reduction in adrenergic reactivity in response to chronic vascular sympatho-activation with phenylephrine. Together these data rule out our hypothesis but suggest that deletion of Ptp1b in POMC neurons protects from leptin- and sympatho-mediated increases in BP. Vascular adrenergic desensitization appears as a protective mechanism against hypertension, and POMC-Ptp1b as a key therapeutic target for the treatment of metabolic and cardiovascular dysfunctions associated with obesity.

  6. Protection of neurons and microglia against ethanol in a mouse model of fetal alcohol spectrum disorders by peroxisome proliferator-activated receptor-γ agonists.

    Science.gov (United States)

    Kane, Cynthia J M; Phelan, Kevin D; Han, Lihong; Smith, Renea R; Xie, Jin; Douglas, James C; Drew, Paul D

    2011-06-01

    Fetal alcohol spectrum disorders (FASD) result from ethanol exposure to the developing fetus and are the most common cause of mental retardation in the United States. These disorders are characterized by a variety of neurodevelopmental and neurodegenerative anomalies which result in significant lifetime disabilities. Thus, novel therapies are required to limit the devastating consequences of FASD. Neuropathology associated with FASD can occur throughout the central nervous system (CNS), but is particularly well characterized in the developing cerebellum. Rodent models of FASD have previously demonstrated that both Purkinje cells and granule cells, which are the two major types of neurons in the cerebellum, are highly susceptible to the toxic effects of ethanol. The current studies demonstrate that ethanol decreases the viability of cultured cerebellar granule cells and microglial cells. Interestingly, microglia have dual functionality in the CNS. They provide trophic and protective support to neurons. However, they may also become pathologically activated and produce inflammatory molecules toxic to parenchymal cells including neurons. The findings in this study demonstrate that the peroxisome proliferator-activated receptor-γ agonists 15-deoxy-Δ12,15 prostaglandin J2 and pioglitazone protect cultured granule cells and microglia from the toxic effects of ethanol. Furthermore, investigations using a newly developed mouse model of FASD and stereological cell counting methods in the cerebellum elucidate that ethanol administration to neonates is toxic to both Purkinje cell neurons as well as microglia, and that in vivo administration of PPAR-γ agonists protects these cells. In composite, these studies suggest that PPAR-γ agonists may be effective in limiting ethanol-induced toxicity to the developing CNS.

  7. CGP37157, an inhibitor of the mitochondrial Na+/Ca2+ exchanger, protects neurons from excitotoxicity by blocking voltage-gated Ca2+ channels.

    Science.gov (United States)

    Ruiz, A; Alberdi, E; Matute, C

    2014-04-10

    Inhibition of the mitochondrial Na(+)/Ca(2+) exchanger (NCLX) by CGP37157 is protective in models of neuronal injury that involve disruption of intracellular Ca(2+) homeostasis. However, the Ca(2+) signaling pathways and stores underlying neuroprotection by that inhibitor are not well defined. In the present study, we analyzed how intracellular Ca(2+) levels are modulated by CGP37157 (10 μM) during NMDA insults in primary cultures of rat cortical neurons. We initially assessed the presence of NCLX in mitochondria of cultured neurons by immunolabeling, and subsequently, we analyzed the effects of CGP37157 on neuronal Ca(2+) homeostasis using cameleon-based mitochondrial Ca(2+) and cytosolic Ca(2+) ([Ca(2+)]i) live imaging. We observed that NCLX-driven mitochondrial Ca(2+) exchange occurs in cortical neurons under basal conditions as CGP37157 induced a decrease in [Ca(2)]i concomitant with a Ca(2+) accumulation inside the mitochondria. In turn, CGP37157 also inhibited mitochondrial Ca(2+) efflux after the stimulation of acetylcholine receptors. In contrast, CGP37157 strongly prevented depolarization-induced [Ca(2+)]i increase by blocking voltage-gated Ca(2+) channels (VGCCs), whereas it did not induce depletion of ER Ca(2+) stores. Moreover, mitochondrial Ca(2+) overload was reduced as a consequence of diminished Ca(2+) entry through VGCCs. The decrease in cytosolic and mitochondrial Ca(2+) overload by CGP37157 resulted in a reduction of excitotoxic mitochondrial damage, characterized here by a reduction in mitochondrial membrane depolarization, oxidative stress and calpain activation. In summary, our results provide evidence that during excitotoxicity CGP37157 modulates cytosolic and mitochondrial Ca(2+) dynamics that leads to attenuation of NMDA-induced mitochondrial dysfunction and neuronal cell death by blocking VGCCs.

  8. Protective effects of curcumin against human immunodeficiency virus 1 gp120 V3 loop-induced neuronal injury in rats

    Institute of Scientific and Technical Information of China (English)

    Zheng Gong; Yanyan Xing; Jun Dong; Lijuan Yang; Hongmei Tang; Rui Pan; Sai Xie; Luyan Guo; Junbin Wang; Qinyin Deng; Guoyin Xiong

    2012-01-01

    Curcumin improves the learning and memory deficits in rats induced by the gp120 V3 loop. The present study cultured rat hippocampal neurons with 1 nM gp120 V3 loop and 1 μM curcumin for 24 hours. The results showed that curcumin inhibited the gp120 V3 loop-induced mitochondrial membrane potential decrease, reduced the mRNA expression of the pro-apoptotic gene caspase-3, and attenuated hippocampal neuronal injury.

  9. Ecdysterone protects gerbil brain from temporal global cerebral ischemia/reperfusion injury via preventing neuron apoptosis and deactivating astrocytes and microglia cells.

    Science.gov (United States)

    Wang, Wei; Wang, Tao; Feng, Wan-Yu; Wang, Zhan-You; Cheng, Mao-Sheng; Wang, Yun-Jie

    2014-01-01

    Ecdysterone (EDS), a common derivative of ecdysteroid, has shown its effects on alleviating cognitive impairment and improving the cognition and memory. However, the mechanisms remain unknown. Using temporal global forebrain ischemia and reperfusion-induced brain injury as a model system, we investigated the roles of EDS in improving cognitive impairment in gerbil. Our results demonstrated that intraperitoneal injection of EDS obviously increased the number of surviving neuron cells by Nissl and neuronal nuclei (NeuN) staining. Indeed, the protecting effects of EDS are because of its ability to prevent the apoptosis of neuron cells as evidenced by TUNEL staining and caspase-3 deactivation in the brain of temporal global forebrain ischemia/reperfusion-treated gerbil. Moreover, EDS administration suppressed the ischemia stimulated activity of astrocytes and microglia cells by inhibiting the production of tumor necrosis alpha (TNF-α) in the brain of gerbil. More importantly, these actions of neurons and astrocytes/microglia cells in response to EDS treatment played pivotal roles in ameliorating the cognitive impairment in the ischemia/reperfusion-injured gerbil. In view of these observations, we not only decipher the mechanisms of EDS in reducing the syndrome of ischemia, but also provide novel perspectives to combat ischemic stroke.

  10. Silibinin activates AMP-activated protein kinase to protect neuronal cells from oxygen and glucose deprivation-re-oxygenation.

    Science.gov (United States)

    Xie, Zhi; Ding, Sheng-quan; Shen, Ya-fang

    2014-11-14

    In this study, we explored the cytoprotective potential of silibinin against oxygen-glucose deprivation (OGD)-induced neuronal cell damages, and studied underling mechanisms. In vitro model of ischemic stroke was created by keeping neuronal cells (SH-SY5Y cells and primary mouse cortical neurons) in an OGD condition followed by re-oxygenation. Pre-treatment of silibinin significantly inhibited OGD/re-oxygenation-induced necrosis and apoptosis of neuronal cells. OGD/re-oxygenation-induced reactive oxygen species (ROS) production and mitochondrial membrane potential (MMP) reduction were also inhibited by silibinin. At the molecular level, silibinin treatment in SH-SY5Y cells and primary cortical neurons led to significant AMP-activated protein kinase (AMPK) signaling activation, detected by phosphorylations of AMPKα1, its upstream kinase liver kinase B1 (LKB1) and the downstream target acetyl-CoA Carboxylase (ACC). Pharmacological inhibition or genetic depletion of AMPK alleviated the neuroprotective ability of silibinin against OGD/re-oxygenation. Further, ROS scavenging ability by silibinin was abolished with AMPK inhibition or silencing. While A-769662, the AMPK activator, mimicked silibinin actions and suppressed ROS production and neuronal cell death following OGD/re-oxygenation. Together, these results show that silibinin-mediated neuroprotection requires activation of AMPK signaling.

  11. Antidepressant Potential of Chlorogenic Acid-Enriched Extract from Eucommia ulmoides Oliver Bark with Neuron Protection and Promotion of Serotonin Release through Enhancing Synapsin I Expression

    Directory of Open Access Journals (Sweden)

    Jianming Wu

    2016-02-01

    Full Text Available Eucommia ulmoides Oliver (E. ulmoides is a traditional Chinese medicine with many beneficial effects, used as a tonic medicine in China and other countries. Chlorogenic acid (CGA is an important compound in E. ulmoides with neuroprotective, cognition improvement and other pharmacological effects. However, it is unknown whether chlorogenic acid-enriched Eucommia ulmoides Oliver bark has antidepressant potential through neuron protection, serotonin release promotion and penetration of blood-cerebrospinal fluid barrier. In the present study, we demonstrated that CGA could stimulate axon and dendrite growth and promote serotonin release through enhancing synapsin I expression in the cells of fetal rat raphe neurons in vitro. More importantly, CGA-enriched extract of E. ulmoides (EUWE at 200 and 400 mg/kg/day orally administered for 7 days showed antidepressant-like effects in the tail suspension test of KM mice. Furthermore, we also found CGA could be detected in the the cerebrospinal fluid of the rats orally treated with EUWE and reach the level of pharmacological effect for neuroprotection by UHPLC-ESI-MS/MS. The findings indicate CGA is able to cross the blood-cerebrospinal fluid barrier to exhibit its neuron protection and promotion of serotonin release through enhancing synapsin I expression. This is the first report of the effect of CGA on promoting 5-HT release through enhancing synapsin I expression and CGA-enriched EUWE has antidepressant-like effect in vivo. EUWE may be developed as the natural drugs for the treatment of depression.

  12. Antidepressant Potential of Chlorogenic Acid-Enriched Extract from Eucommia ulmoides Oliver Bark with Neuron Protection and Promotion of Serotonin Release through Enhancing Synapsin I Expression.

    Science.gov (United States)

    Wu, Jianming; Chen, Haixia; Li, Hua; Tang, Yong; Yang, Le; Cao, Shousong; Qin, Dalian

    2016-02-25

    Eucommia ulmoides Oliver (E. ulmoides) is a traditional Chinese medicine with many beneficial effects, used as a tonic medicine in China and other countries. Chlorogenic acid (CGA) is an important compound in E. ulmoides with neuroprotective, cognition improvement and other pharmacological effects. However, it is unknown whether chlorogenic acid-enriched Eucommia ulmoides Oliver bark has antidepressant potential through neuron protection, serotonin release promotion and penetration of blood-cerebrospinal fluid barrier. In the present study, we demonstrated that CGA could stimulate axon and dendrite growth and promote serotonin release through enhancing synapsin I expression in the cells of fetal rat raphe neurons in vitro. More importantly, CGA-enriched extract of E. ulmoides (EUWE) at 200 and 400 mg/kg/day orally administered for 7 days showed antidepressant-like effects in the tail suspension test of KM mice. Furthermore, we also found CGA could be detected in the the cerebrospinal fluid of the rats orally treated with EUWE and reach the level of pharmacological effect for neuroprotection by UHPLC-ESI-MS/MS. The findings indicate CGA is able to cross the blood-cerebrospinal fluid barrier to exhibit its neuron protection and promotion of serotonin release through enhancing synapsin I expression. This is the first report of the effect of CGA on promoting 5-HT release through enhancing synapsin I expression and CGA-enriched EUWE has antidepressant-like effect in vivo. EUWE may be developed as the natural drugs for the treatment of depression.

  13. Application of the Co-culture Membrane System Pointed to a Protective Role of Catestatin on Hippocampal Plus Hypothalamic Neurons Exposed to Oxygen and Glucose Deprivation.

    Science.gov (United States)

    Mele, Maria; Morelli, Sabrina; Fazzari, Gilda; Avolio, Ennio; Alò, Raffaella; Piscioneri, Antonella; De Bartolo, Loredana; Facciolo, Rosa Maria; Canonaco, Marcello

    2016-11-05

    Depletion of oxygen and glucose even for brief periods is sufficient to cause cerebral ischemia, which is a predominant worldwide cause of motor deficits with the reduction of life quality and subsequently death. Hence, more insights regarding protective measures against ischemic events are becoming a major research goal. Among the many neuronal factors, N-methyl-D-aspartate receptors (NMDAR), orexinergic neuroreceptors (ORXR), and sympatho-inhibitory neuropeptide catestatin (CST) are widely involved with ischemic episodes. In this study, it was possible to induce in vitro ischemic conditions of the hamster (Mesocricetus auratus) hippocampal and hypothalamic neuronal cultures, grown on a newly compartmentalized membrane system, via oxygen and glucose deprivation (OGD). These cultures displayed notably differentiated NMDARergic and ORXergic receptor expression activities along with evident brain-derived neurotrophic factor (BDNF) plus orexin A (ORX-A) secretion, especially under co-cultured conditions. Interestingly, addition of CST in OGD-insulted hippocampal cells accounted for upregulated GluN1 and ORX1R transcripts that in the case of the latter neuroreceptor was very strongly (p BDNF and ORX-A secretion in the presence of hippocampal cells. Overall, the preferential CST effects on BDNF plus ORX-A production together with altered NMDAR and ORXR levels, especially in co-cultured hypothalamic cells pointed to ORX-containing neurons as major protective constituents against ischemic damages thus opening new scenarios on the cross-talking roles of CST during ischemic disorders.

  14. Protection of ischemic postconditioning against neuronal apoptosis induced by transient focal ischemia is associated with attenuation of NF-κB/p65 activation.

    Directory of Open Access Journals (Sweden)

    Jianmin Liang

    Full Text Available BACKGROUND AND PURPOSE: Accumulating evidences have demonstrated that nuclear factor κB/p65 plays a protective role in the protection of ischemic preconditioning and detrimental role in lethal ischemia-induced programmed cell death including apoptosis and autophagic death. However, its role in the protection of ischemic postconditioning is still unclear. METHODS: Rat MCAO model was used to produce transient focal ischemia. The procedure of ischemic postconditioning consisted of three cycles of 30 seconds reperfusion/reocclusion of MCA. The volume of cerebral infarction was measured by TTC staining and neuronal apoptosis was detected by TUNEL staining. Western blotting was used to analyze the changes in protein levels of Caspase-3, NF-κB/p65, phosphor- NF-κB/p65, IκBα, phosphor- IκBα, Noxa, Bim and Bax between rats treated with and without ischemic postconditioning. Laser scanning confocal microscopy was used to examine the distribution of NF-κB/p65 and Noxa. RESULTS: Ischemic postconditioning made transient focal ischemia-induced infarct volume decrease obviously from 38.6% ± 5.8% to 23.5% ± 4.3%, and apoptosis rate reduce significantly from 46.5% ± 6.2 to 29.6% ± 5.3% at reperfusion 24 h following 2 h focal cerebral ischemia. Western blotting analysis showed that ischemic postconditioning suppressed markedly the reduction of NF-κB/p65 in cytoplasm, but elevated its content in nucleus either at reperfusion 6 h or 24 h. Moreover, the decrease of IκBα and the increase of phosphorylated IκBα and phosphorylated NF-κB/p65 at indicated reperfusion time were reversed by ischemic postconditioning. Correspondingly, proapoptotic proteins Caspase-3, cleaved Caspase-3, Noxa, Bim and Bax were all mitigated significantly by ischemic postconditioning. Confocal microscopy revealed that ischemic postconditioning not only attenuated ischemia-induced translocation of NF-κB/p65 from neuronal cytoplasm to nucleus, but also inhibited the abnormal

  15. Clinical Significance of the Detection of CD55, CD59 Expression Deletion in Patients with Cytopenia%血细胞减少患者衰变加速因子和膜反应性溶血抑制物表达缺失检测的临床意义

    Institute of Scientific and Technical Information of China (English)

    吕敏; 朱焕玲; 蒋能刚; 曾婷婷

    2012-01-01

    目的 检测血细胞减少患者外周血红细胞和中性粒细胞细胞膜糖基磷脂酰肌醇(GPI)连接的补体调节蛋白衰变加速因子(CD55)和膜反应性溶血抑制物(CD59)表达情况,并探讨其临床意义.方法 2006年7月-2011年3月,采用直接免疫荧光标记法流式细胞仪检测182例血细胞减少患者外周血CD55及CD59表达情况,其中阵发性睡眠性血红蛋白尿(PNH)9例,再生障碍性贫血(AA) -PNH综合征8例,AA 83例,骨髓增生异常综合征51例,自身免疫性溶血性贫血11例,造血功能停滞6例,缺铁性贫血7例,巨幼细胞性贫血4例,脾功能亢进3例.结果 PNH及AA-PNH患者CD55、CD59抗原缺失率均较其他血细胞减少者明显增高.结论 流式细胞仪检测外周血中红细胞和中性粒细胞膜CD55和CD59抗原表达缺失率是目前诊断PNH可靠和敏感的方法,也是对PNH、AA-PNH早期诊断敏感指标,并且PNH克隆检测还能为诊断疾病提供鉴别诊断依据.%Objective To explore the expression of decaying accelerating factor (CD55) and membrane inhibitor of reactive lysis (CD59) connected with glycosylphosphatidylinositol (GPI) on the membranes of peripheral blood cells and neutrophils in patients with cytopenia, and research on their clinical significance. Methods From July 2006 to March 2011, By directing immunofiuorescence flow cytometry, we detected the expression levels of CD55 and CD59 in 182 patients with cytopenia. Among them, there were 9 cases of paroxysmal nocturnal hemoglobinuria (PNH), 8 cases of aplastic anemia-PNH (AA-PNH), 83 cases of aplastic anemia (AA), 51 cases of myelodysplastic syndrome, 11 cases of autoimmune hemolytic anemia, 6 cases of aplastic crisis, 7 cases of iron deficiency anemia, 4 cases of megaloblastic anemia and 3 cases of hypersplenism. Results CD55 and CD59 antigens deficiency was more significant in PNH, AA-PNH patients than in other cytopenic patients. Conclusions Detection of CD55 and CD59 antigens deficiency

  16. 肌萎灵冻干粉对运动神经元的保护作用%Protective effects of Jiweiling lyophilized powder on the motor neurons

    Institute of Scientific and Technical Information of China (English)

    张秋艳; 王玲玲; 张东蛟; 王宏涛; 张会欣; 刘克剑; 崔庆飞; 宋剑; 赵韶华

    2011-01-01

    目的 观察肌萎灵冻干粉对大鼠脊髓损伤后的神经保护作用,并研究其对谷氨酸诱导的原代神经细胞凋亡的影响.方法 以质量30 g静态压迫硬膜外脊髓10 min建立大鼠脊髓损伤模型,于术后第1天、7天、14天进行各实验组神经功能评价,并观察损伤处脊髓形态学改变;建立低浓度谷氨酸诱导原代神经细胞的兴奋性毒性损伤模型,MTT法检测细胞活力,流式细胞仪检测细胞凋亡率,Western检测Bcl-2、Bax蛋白表达变化.结果 (1)肌萎灵冻干粉可明显提高脊髓损伤大鼠各时间段的BBB评分,改善后肢运动功能,减轻脊髓神经元水肿.(2)肌萎灵冻干粉可增强谷氨酸损伤后的神经细胞活力,缓解神经细胞损伤.(3)肌萎灵冻干粉能显著减少谷氨酸诱导的神经细胞凋亡.(4)肌萎灵冻干粉可不同程度的上调Bcl-2蛋白表达,下调Bax蛋白表达.结论 肌萎灵冻干粉可促进脊髓损伤大鼠后肢运动功能恢复,增强神经细胞活力,抑制谷氨酸诱导的神经细胞凋亡,调节凋亡相关蛋白表达,具有一定的神经保护作用.%Objective To observe the protective effects of Jiweiling lyophilized powder ( JWLF ) on the neuron of spinal cord injury ( SCI ) rats, and the influence on primary neuron apoptosis induced by glutamate in vitro, also explore the molecular mechanism of JWLF on the motor neuron disease ( MND ). Methods The SCI model of rats were developed with static compressive pressure of 30 g on the spinal epidural for 10 min, the neuron function was evaluated at 1 d,7 d and 14 d after the surgery and the morphologic changes of the damaged spinal were determined. The primary cortical neuron was damaged by glutamate at low concentration, then measure the viability and the expression of Bcl-2,Bax with methods of MTT, flow cytometry and Western blot. Results ( 1 )JWLF could obviously improve BBB rating score on SCI rats at different time and release the edema of spinal neurons. ( 2

  17. Intrastriatal glial cell line-derived neurotrophic factors for protecting dopaminergic neurons in the substantia nigra of mice with Parkinson disease

    Institute of Scientific and Technical Information of China (English)

    Chenghua Xiao; Yanqiang Wang; Hongmei Liu; Hongjun Wang; Junping Cao; Dianshuai Gao

    2007-01-01

    BACKGROUND: Substantia nigra is deep in position and limited in range, the glial cell line-derived neurotrophic factor (GDNF) injection directly into substantia nigra has relatively greater damages with higher difficulty. GDNF injection into striatum, the target area of dopaminergic neuron, may protect the dopaminergic neurons in the compact part of substantia nigra through retrograde transport.OBJECTIVE: To investigate the protective effect of intrastriatal GDNF on dopaminergic neurons in the substantia nigra of mice with Parkinson disease (PD), and analyze the action pathway.DESIGN: A controlled observation.SETTING: Neurobiological Laboratory of Xuzhou Medical College.MATERIALS: Twenty-four male Kunming mice of 7 - 8 weeks old were used. GDNF,1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) were purchased from Sigma Company (USA);LEICAQWin image processing and analytical system.METHODS: The experiments were carried out in the Neurobiological Laboratory of Xuzhou Medical College from September 2005 to October 2006. The PD models were established in adult KunMing mice by intraperitoneal injection of MPTP. The model mice were were randomly divided into four groups with 6 mice in each group: GDNF 4-day group, phosphate buffer solution (PSB) 4-day group, GDNF 6-day group and PSB 6-day group. Mice in the GDNF 4 and 6-day groups were administrated with 1 μL GDNF solution (20 μg/L, dispensed with 0.01 mol/L PBS) injected into right striatum at 4 and 6 days after model establishment. Mice in the PSB 4 and 6-day groups were administrated with 0.01 mol/L PBS of the same volume to the same injection at corresponding time points. ② On the 12th day after model establishment, the midbrain tissue section of each mice was divided into 3 areas from rostral to caudal sides. The positive neurons of tyroxine hydroxylase (TH) and calcium binding protein (CB) with obvious nucleolus and clear outline were randomly selected for the measurement, and the number of positive neurons

  18. Fibroblast growth factor 10 protects neuron against oxygen–glucose deprivation injury through inducing heme oxygenase-1

    Energy Technology Data Exchange (ETDEWEB)

    Li, Yong-Hua; Yang, Li-Ye; Chen, Wei; Li, Ying-Ke, E-mail: liyingke6f@126.com; Yuan, Hong-Bin, E-mail: yuanhongbin6f@126.com

    2015-01-02

    Highlights: • FGF10 attenuates OGD induced injury in cortical neuron. • FGF10 reduces OGD triggered ROS level in cortical neuron. • FGF10 induces HO-1 expression upon OGD stimuli in cortical neuron. • Knockdown of HO-1 impairs the neuroprotection of FGF10 in OGD model. - Abstract: Fibroblast growth factors (FGFs) are a family of structurally related heparin-binding proteins with diverse biological functions. FGFs participate in mitogenesis, angiogenesis, cell proliferation, development, differentiation and cell migration. Here, we investigated the potential effect of FGF10, a member of FGFs, on neuron survival in oxygen–glucose deprivation (OGD) model. In primary cultured mouse cortical neurons upon OGD, FGF10 treatment (100 and 1000 ng/ml) attenuated the decrease of cell viability and rescued the LDH release. Tuj-1 immunocytochemistry assay showed that FGF10 promoted neuronal survival. Apoptosis assay with Annexin V + PI by flow cytometry demonstrated that FGF10 treatment reduced apoptotic cell proportion. Moreover, immunoblotting showed that FGF10 alleviated the cleaved caspase-3 upregulation caused by OGD. FGF10 treatment also depressed the OGD-induced increase of caspase-3, -8 and -9 activities. At last, we found FGF10 triggered heme oxygenase-1 (HO-1) protein expression rather than hypoxia-inducible factor-1 (HIF-1), AMP-activated protein kinase (AMPK) signaling and extracellular signal-regulated kinases 1/2 (ERK1/2) signaling. Knockdown of HO-1 by siRNA partly abolished the neuroprotection of FGF10 in OGD model. In summary, our observations provide the first evidence for the neuroprotective function of FGF10 against ischemic neuronal injury and suggest that FGF10 may be a promising agent for treatment of ischemic stroke.

  19. Vascular endothelial growth factor is up-regulated after status epilepticus and protects against seizure-induced neuronal loss in hippocampus.

    Science.gov (United States)

    Nicoletti, J N; Shah, S K; McCloskey, D P; Goodman, J H; Elkady, A; Atassi, H; Hylton, D; Rudge, J S; Scharfman, H E; Croll, S D

    2008-01-02

    Vascular endothelial growth factor (VEGF) is a protein factor which has been found to play a significant role in both normal and pathological states. Its role as an angiogenic factor is well-established. More recently, VEGF has been shown to protect neurons from cell death both in vivo and in vitro. While VEGF's potential as a protective factor has been demonstrated in hypoxia-ischemia, in vitro excitotoxicity, and motor neuron degeneration, its role in seizure-induced cell loss has received little attention. A potential role in seizures is suggested by Newton et al.'s [Newton SS, Collier EF, Hunsberger J, Adams D, Terwilliger R, Selvanayagam E, Duman RS (2003) Gene profile of electroconvulsive seizures: Induction of neurotrophic and angiogenic factors. J Neurosci 23:10841-10851] finding that VEGF mRNA increases in areas of the brain that are susceptible to cell loss after electroconvulsive-shock induced seizures. Because a linear relationship does not always exist between expression of mRNA and protein, we investigated whether VEGF protein expression increased after pilocarpine-induced status epilepticus. In addition, we administered exogenous VEGF in one experiment and blocked endogenous VEGF in another to determine whether VEGF exerts a neuroprotective effect against status epilepticus-induced cell loss in one vulnerable brain region, the rat hippocampus. Our data revealed that VEGF is dramatically up-regulated in neurons and glia in hippocampus, thalamus, amygdala, and neocortex 24 h after status epilepticus. VEGF induced significant preservation of hippocampal neurons, suggesting that VEGF may play a neuroprotective role following status epilepticus.

  20. Imipramine protects against the deleterious effects of chronic corticosterone on depression-like behavior, hippocampal reelin expression, and neuronal maturation.

    Science.gov (United States)

    Fenton, Erin Y; Fournier, Neil M; Lussier, April L; Romay-Tallon, Raquel; Caruncho, Hector J; Kalynchuk, Lisa E

    2015-07-03

    We have hypothesized that a downregulation of reelin and deficient maturation of adult-born hippocampal neurons are important factors in the pathogenesis of depression. This hypothesis is based on previous work showing that depression-like behavior in rats treated with protracted corticosterone develops in concert with decreased dendritic complexity in newborn hippocampal granule neurons and decreased reelin expression in the proliferative subgranular zone of the dentate gyrus. In addition, heterozygous reeler mice with approximately 50% of normal brain levels of reelin are more vulnerable to the depressogenic effects of corticosterone than wild-type mice. The purpose of this experiment was to provide pharmacological validation for the link between reelin, neuronal maturation, and depression by examining whether the deleterious effects of corticosterone on these measures could be prevented by co-administration of the antidepressant imipramine. Rats received corticosterone injections, corticosterone injections plus either 10 or 15mg/kg imipramine injections, or vehicle injections for 21 consecutive days. They were then subjected to the forced swim test to assess depression-like behavior and sacrificed for immunohistochemical examination of immature neuron number and dendritic complexity and the presence of reelin+cells. We found that corticosterone increases depression-like behavior, decreases the number of reelin+cells in the subgranular zone, and decreases the number and complexity of immature neurons in the granule cell layer. All of these behavioral and cellular phenotypes were prevented by imipramine, providing further support for the idea that reelin is involved in the pathogenesis of depression.

  1. Minocycline inhibited the pro-apoptotic effect of microglia on neural progenitor cells and protected their neuronal differentiation in vitro.

    Science.gov (United States)

    Liu, Xuqing; Su, Huanxing; Chu, Tak-Ho; Guo, Anchen; Wu, Wutian

    2013-05-10

    Neural progenitor cell (NPC) transplantation offers great potential to treat spinal cord injury (SCI), but their efficiency is limited by poor survival and neuronal differentiation after transplantation. In the injury site, microglia may become activated and participate in the inflammation reaction. In vitro studies indicated that activated microglia might impair NPC survival and neuronal differentiation, but resting microglia did not. This study investigated the potential of minocycline to modify the negative effects of activated microglia on NPCs in vitro. First, the direct effects of minocycline on NPCs were tested. The results showed that at the concentration of 10μg/ml or lower, minocycline did not affect NPC survival and proliferation, but impaired neuronal differentiation. Then microglia were activated with lipopolysaccharide (LPS) or treated with LPS plus minocycline (LPSMC), and the effects of conditioned media on NPC apoptosis and differentiation were studied. The results showed that, compared with LPS treatment group, the microglia conditioned media of LPSMC treatment group resulted in a significantly lower apoptotic rate of NPCs, and increased the neuronal differentiation of NPCs. This suggested that minocycline might inhibit the negative effects of microglia on NPCs, and have the potential to support the survival and neuronal differentiation of transplanted NPCs for SCI.

  2. A physically-modified saline suppresses neuronal apoptosis, attenuates tau phosphorylation and protects memory in an animal model of Alzheimer's disease.

    Science.gov (United States)

    Modi, Khushbu K; Jana, Arundhati; Ghosh, Supurna; Watson, Richard; Pahan, Kalipada

    2014-01-01

    Alzheimer's disease (AD), the leading cause of dementia in the aging population, is characterized by the presence of neuritic plaques, neurofibrillary tangles and extensive neuronal apoptosis. Neuritic plaques are mainly composed of aggregates of amyloid-β (Aβ) protein while neurofibrillary tangles are composed of the hyperphosphorylated tau protein. Despite intense investigations, no effective therapy is currently available to halt the progression of this disease. Here, we have undertaken a novel approach to attenuate apoptosis and tau phosphorylation in cultured neuronal cells and in a transgenic animal model of AD. RNS60 is a 0.9% saline solution containing oxygenated nanobubbles that is generated by subjecting normal saline to Taylor-Couette-Poiseuille (TCP) flow under elevated oxygen pressure. In our experiments, fibrillar Aβ1-42, but not the reverse peptide Aβ42-1, induced apoptosis and cell death in human SHSY5Y neuronal cells. RNS60, but not NS (normal saline), RNS10.3 (TCP-modified saline without excess oxygen) or PNS60 (saline containing excess oxygen without TCP modification), attenuated Aβ(1-42)-induced cell death. RNS60 inhibited neuronal cell death via activation of the type 1A phosphatidylinositol-3 (PI-3) kinase-Akt-BAD pathway. Furthermore, RNS60 also decreased Aβ(1-42)-induced tau phosphorylation via (PI-3 kinase-Akt)-mediated inhibition of GSK-3β. Similarly, RNS60 treatment suppressed neuronal apoptosis, attenuated Tau phosphorylation, inhibited glial activation, and reduced the burden of Aβ in the hippocampus and protected memory and learning in 5XFAD transgenic mouse model of AD. Therefore, RNS60 may be a promising pharmaceutical candidate in halting or delaying the progression of AD.

  3. A physically-modified saline suppresses neuronal apoptosis, attenuates tau phosphorylation and protects memory in an animal model of Alzheimer's disease.

    Directory of Open Access Journals (Sweden)

    Khushbu K Modi

    Full Text Available Alzheimer's disease (AD, the leading cause of dementia in the aging population, is characterized by the presence of neuritic plaques, neurofibrillary tangles and extensive neuronal apoptosis. Neuritic plaques are mainly composed of aggregates of amyloid-β (Aβ protein while neurofibrillary tangles are composed of the hyperphosphorylated tau protein. Despite intense investigations, no effective therapy is currently available to halt the progression of this disease. Here, we have undertaken a novel approach to attenuate apoptosis and tau phosphorylation in cultured neuronal cells and in a transgenic animal model of AD. RNS60 is a 0.9% saline solution containing oxygenated nanobubbles that is generated by subjecting normal saline to Taylor-Couette-Poiseuille (TCP flow under elevated oxygen pressure. In our experiments, fibrillar Aβ1-42, but not the reverse peptide Aβ42-1, induced apoptosis and cell death in human SHSY5Y neuronal cells. RNS60, but not NS (normal saline, RNS10.3 (TCP-modified saline without excess oxygen or PNS60 (saline containing excess oxygen without TCP modification, attenuated Aβ(1-42-induced cell death. RNS60 inhibited neuronal cell death via activation of the type 1A phosphatidylinositol-3 (PI-3 kinase-Akt-BAD pathway. Furthermore, RNS60 also decreased Aβ(1-42-induced tau phosphorylation via (PI-3 kinase-Akt-mediated inhibition of GSK-3β. Similarly, RNS60 treatment suppressed neuronal apoptosis, attenuated Tau phosphorylation, inhibited glial activation, and reduced the burden of Aβ in the hippocampus and protected memory and learning in 5XFAD transgenic mouse model of AD. Therefore, RNS60 may be a promising pharmaceutical candidate in halting or delaying the progression of AD.

  4. Curcumin protects neurons against oxygen-glucose deprivation/reoxygenation-induced injury through activation of peroxisome proliferator-activated receptor-γ function.

    Science.gov (United States)

    Liu, Zun-Jing; Liu, Hong-Qiang; Xiao, Cheng; Fan, Hui-Zhen; Huang, Qing; Liu, Yun-Hai; Wang, Yu

    2014-11-01

    The turmeric derivative curcumin protects against cerebral ischemic injury. We previously demonstrated that curcumin activates peroxisome proliferator-activated receptor-γ (PPARγ), a ligand-activated transcription factor involved in both neuroprotective and anti-inflammatory signaling pathways. This study tested whether the neuroprotective effects of curcumin against oxygen-glucose deprivation/reoxygenation (OGD/R)-induced injury of rat cortical neurons are mediated (at least in part) by PPARγ. Curcumin (10 μM) potently enhanced PPARγ expression and transcriptional activity following OGD/R. In addition, curcumin markedly increased neuronal viability, as evidenced by decreased lactate dehydrogenase release and reduced nitric oxide production, caspase-3 activity, and apoptosis. These protective effects were suppressed by coadministration of the PPARγ antagonist 2-chloro-5-nitrobenzanilide (GW9662) and by prior transfection of a small-interfering RNA (siRNA) targeting PPARγ, treatments that had no toxic effects on healthy neurons. Curcumin reduced OGD/R-induced accumulation of reactive oxygen species and inhibited the mitochondrial apoptosis pathway, as indicated by reduced release of cytochrome c and apoptosis-inducing factor and maintenance of both the mitochondrial membrane potential and the Bax/Bcl-2 ratio. Again, GW9662 or PPARγ siRNA transfection mitigated the protective effects of curcumin on mitochondrial function. Curcumin suppressed IκB kinase phosphorylation and IκB degradation, thereby inhibiting nuclear factor-κ B (NF-κB) nuclear translocation, effects also blocked by GW9662 or PPARγ siRNA. Immunoprecipitation experiments revealed that PPARγ interacted with NF-κB p65 and inhibited NF-κB activation. The present study provides strong evidence that at least some of the neuroprotective effects of curcumin against OGD/R are mediated by PPARγ activation.

  5. Gastro-protective action of lafutidine mediated by capsaicin-sensitive afferent neurons without interaction with TRPV1 and involvement of endogenous prostaglandins

    Institute of Scientific and Technical Information of China (English)

    Kazuhiro Fukushima; Yoko Aoi; Shinichi Kato; Koji Takeuchi

    2006-01-01

    AIM: Lafutidine, a histamine H2 receptor antagonist,exhibits gastro-protective action mediated by capsaicinsensitive afferent neurons (CSN). We compared the effect between lafutidine and capsaicin, with respect to the interaction with endogenous prostaglandins (PG), nitric oxide (NO) and the afferent neurons, including transient receptor potential vanilloid subtype 1 (TRPV1).METHODS: Male SD rats and C57BL/6 mice, both wildtype and prostacyclin IP receptor knockout animals, were used after 18 h of fasting. Gastric lesions were induced by the po administration of HCI/ethanol (60% in 150 mmol/L HCI) in a volume of 1 mL for rats or 0.3 mL for mice.RESULTS: Both lafutidine and capsaicin (1-10 mg/kg,po) afforded dose-dependent protection against HCI/ethanol in rats and mice. The effects were attenuated by both the ablation of CSN and pretreatment with NG-nitroL-arginine methyl ester, yet only the effect of capsaicin was mitigated by prior administration of capsazepine, the TRPV1 antagonist, as well as indomethacin. Lafutidine protected the stomach against HCI/ethanol in IP receptor knockout mice, similar to wild-type animals, while capsaicin failed to afford protection in the animals lacking IP receptors. Neither of these agents affected the mucosal PGE2 or 6-keto PGF1α contents in rat stomachs. Capsaicin evoked an increase in [Ca2+]i in rat TRPV1-transfected HEK293 cells while lafutidine did not.CONCLUSION: These results suggest that although both lafutidine and capsaicin exhibit gastro-protective action mediated by CSN, the mode of their effects differs regarding the dependency on endogenous PGs/IP receptors and TRPV1. It is assumed that lafutidine interacts with CSN at yet unidentified sites other than TRPV1.

  6. Expression of c-Fos protein and nitricoxide synthase in neurons of cerebral cortex from fetal rats in hypoxia and protective role of Angelica sinensis

    Institute of Scientific and Technical Information of China (English)

    Hong Yu; Hongxian Zhao; Yuling Wu

    2006-01-01

    BACKGROUND: Both c-Fos protein and nitricoxide synthase (NOS) have been used as general indexes in relative research about neurons, but it is lack of reports that c-Fos protein and NOS are applied synchronously to study the neurons of hypoxic fetal rats in uterus.OBJECTIVE: To study the effect of hypoxia in uterus on the expression of c-Fos protein and NOS in neurons of cerebral cortex from fetal rats and whether Angelica sinensis has the protective effect on these neurons in hypoxia.DESIGN: Randomized control experiment.SETTING: Department of Histology and Embryology, Luzhou Medical College.MATERIALS: Twelve adult female Wistar rats in oestrum and 1 male Wistar rat with bodymass from 220 to 250 g were chosen. Parenteral solution of Angelica sinensis mainly contained angelica sinensis, 10 mL/ampoule, was provided by Department of Agent of the Second Hospital Affiliated to Hubei Medical University (batch number: 01062310).METHODS: This experiment was completed in the Department of Histology and Embryology of Luzhou Medical College from September 2003 to June 2004. ① Twelve adult female Wistar rats in oestrum and 1 male Wistar rat were housed in one rearing cage. Vaginal embolus was performed on conceive female rat at 8:00 am next day.On the 15th conceiving day,all conceiving rats were divided randomly into three groups:control group, hypoxia group and Angelica group with 4 in each group. Rats in hypoxia group and Angelica group were modeled with hypotonic hypoxia in uterus. Angelica group: Rats were injected with 8 mL/kg Angelica sinensis injection through caudal veins before hypoxia.Hypoxia group:Rats were injected with the same volume of saline.Control group:Rats were not modeled and fed with normal way. ② Twenty embryos of rats were chosen randomly from each group and then routinely embedded in paraffin. Paraffin sections were cut from the brain of embryos to anterior fontanelle. Double-label staining was used to detect the expression of nNOS and c-Fos in

  7. Lack of TNF-alpha receptor type 2 protects motor neurons in a cellular model of amyotrophic lateral sclerosis and in mutant SOD1 mice but does not affect disease progression.

    Science.gov (United States)

    Tortarolo, Massimo; Vallarola, Antonio; Lidonnici, Dario; Battaglia, Elisa; Gensano, Francesco; Spaltro, Gabriella; Fiordaliso, Fabio; Corbelli, Alessandro; Garetto, Stefano; Martini, Elisa; Pasetto, Laura; Kallikourdis, Marinos; Bonetto, Valentina; Bendotti, Caterina

    2015-10-01

    Changes in the homeostasis of tumor necrosis factor α (TNFα) have been demonstrated in patients and experimental models of amyotrophic lateral sclerosis (ALS). However, the contribution of TNFα to the development of ALS is still debated. TNFα is expressed by glia and neurons and acts through the membrane receptors TNFR1 and TNFR2, which may have opposite effects in neurodegeneration. We investigated the role of TNFα and its receptors in the selective motor neuron death in ALS in vitro and in vivo. TNFR2 expressed by astrocytes and neurons, but not TNFR1, was implicated in motor neuron loss in primary SOD1-G93A co-cultures. Deleting TNFR2 from SOD1-G93A mice, there was partial but significant protection of spinal motor neurons, sciatic nerves, and tibialis muscles. However, no improvement of motor impairment or survival was observed. Since the sciatic nerves of SOD1-G93A/TNFR2-/- mice showed high phospho-TAR DNA-binding protein 43 (TDP-43) accumulation and low levels of acetyl-tubulin, two indices of axonal dysfunction, the lack of symptom improvement in these mice might be due to impaired function of rescued motor neurons. These results indicate the interaction between TNFR2 and membrane-bound TNFα as an innovative pathway involved in motor neuron death. Nevertheless, its inhibition is not sufficient to stop disease progression in ALS mice, underlining the complexity of this pathology. We show evidence of the involvement of neuronal and astroglial TNFR2 in the motor neuron degeneration in ALS. Both concur to cause motor neuron death in primary astrocyte/spinal neuron co-cultures. TNFR2 deletion partially protects motor neurons and sciatic nerves in SOD1-G93A mice but does not improve their symptoms and survival. However, TNFR2 could be a new target for multi-intervention therapies.

  8. Adenosine A(2B) receptor-mediated leukemia inhibitory factor release from astrocytes protects cortical neurons against excitotoxicity

    NARCIS (Netherlands)

    Moidunny, Shamsudheen; Vinet, Jonathan; Wesseling, Evelyn; Bijzet, Johan; Shieh, Chu-Hsin; van Ijzendoorn, Sven C.D.; Bezzi, Paola; Boddeke, Hendrikus W.G.M.; Biber, Knut

    2012-01-01

    Background: Neuroprotective and neurotrophic properties of leukemia inhibitory factor (LIF) have been widely reported. In the central nervous system (CNS), astrocytes are the major source for LIF, expression of which is enhanced following disturbances leading to neuronal damage. How astrocytic LIF e

  9. Quercetin and sesamin protect neuronal PC12 cells from high-glucose-induced oxidation, nitrosative stress, and apoptosis.

    Science.gov (United States)

    Bournival, Julie; Francoeur, Marc-André; Renaud, Justine; Martinoli, Maria-Grazia

    2012-06-01

    Complications of diabetes are now well-known to affect sensory, motor, and autonomic nerves. Diabetes is also thought to be involved in neurodegenerative processes characteristic of several neurodegenerative diseases. Indeed, it has been acknowledged recently that hyperglycemia-induced oxidative stress contributes to numerous cellular reactions typical of central nervous system deterioration. The goal of the present study was to evaluate the effects of the polyphenol quercetin and the lignan sesamin on high-glucose (HG)-induced oxidative damage in an in vitro model of dopaminergic neurons, neuronal PC12 cells. When incubated with HG (13.5 mg/mL), neuronal PC12 cells showed a significant increase of cellular death. Our results revealed that quercetin and sesamin defend neuronal PC12 cells from HG-induced cellular demise. An elevated level of reactive oxygen and nitrogen species is a consequence of improved oxidative stress after HG administration, and we demonstrated that this production diminishes with quercetin and sesamin treatment. We also found that quercetin and sesamin elicited an increment of superoxide dismutase activity. DNA fragmentation, Bax/Bcl-2 ratio, nuclear translocation of apoptosis-inducing factor, as well as poly(adenosine diphosphate [ADP]-ribose) polymerase cleavage were significantly reduced by quercetin and sesamin administration, affirming their antiapoptotic features. Also, HG treatment impacted caspase-3 cleavage, supporting caspase-3-dependent pathways as mechanisms of apoptotic death. Our results indicate a powerful role for these natural dietary compounds and emphasize preventive or complementary nutritional strategies for diabetes control.

  10. Fibroblast growth factor 10 protects neuron against oxygen-glucose deprivation injury through inducing heme oxygenase-1.

    Science.gov (United States)

    Li, Yong-Hua; Yang, Li-Ye; Chen, Wei; Li, Ying-Ke; Yuan, Hong-Bin

    2015-01-02

    Fibroblast growth factors (FGFs) are a family of structurally related heparin-binding proteins with diverse biological functions. FGFs participate in mitogenesis, angiogenesis, cell proliferation, development, differentiation and cell migration. Here, we investigated the potential effect of FGF10, a member of FGFs, on neuron survival in oxygen-glucose deprivation (OGD) model. In primary cultured mouse cortical neurons upon OGD, FGF10 treatment (100 and 1000 ng/ml) attenuated the decrease of cell viability and rescued the LDH release. Tuj-1 immunocytochemistry assay showed that FGF10 promoted neuronal survival. Apoptosis assay with Annexin V+PI by flow cytometry demonstrated that FGF10 treatment reduced apoptotic cell proportion. Moreover, immunoblotting showed that FGF10 alleviated the cleaved caspase-3 upregulation caused by OGD. FGF10 treatment also depressed the OGD-induced increase of caspase-3, -8 and -9 activities. At last, we found FGF10 triggered heme oxygenase-1 (HO-1) protein expression rather than hypoxia-inducible factor-1 (HIF-1), AMP-activated protein kinase (AMPK) signaling and extracellular signal-regulated kinases 1/2 (ERK1/2) signaling. Knockdown of HO-1 by siRNA partly abolished the neuroprotection of FGF10 in OGD model. In summary, our observations provide the first evidence for the neuroprotective function of FGF10 against ischemic neuronal injury and suggest that FGF10 may be a promising agent for treatment of ischemic stroke.

  11. Hypoxia pretreatment and EPO-modification enhance the protective effects of MSC on neuron-like PC12 cells in a similar way.

    Science.gov (United States)

    Feng, Jinli; Wang, Wei

    2017-01-08

    Mesenchymal stem cells (MSC) based cell transplantation therapy is proved to be an attractive strategy with great potential for improvement of hypoxia induced neural damage. In the present study, MSCs were co-culture with PC12 to investigate its protective effects against hypoxia pretreatment, and the Lactate dehydrogenase (LDH) release assay, MTT and Anexin V staining were performed to analysis the cellular damage or apoptotic. RT-PCR and Western blotting were further used to investigate the underlying mechanism. The results indicate that hypoxia treatment results in the decrease of PC12 cell viability, yet co-culture with MSC could protect the PC12 from hypoxia induced damage. Hypoxia pre-activated or EPO transduced MSC with up-regulated erythropoietin (EPO) expression could further enhance MSC's protective effect against hypoxia induced cell damage, which was associated with high level of anti-apoptotic p-Akt and ration Bcl-2/Bax, and decreased Caspase 3 in PC12. Taken together, these data suggests high levels of MSC-mediated cyto-protection is closely tied to high gene expression levels of EPO. The up-regulation of EPO for enhanced MSC-mediated cyto-protection may has great potential for the MSC cellular therapy of neural or neuronal injuries induced by hypoxia.

  12. Adenosine A2B receptor-mediated leukemia inhibitory factor release from astrocytes protects cortical neurons against excitotoxicity

    Directory of Open Access Journals (Sweden)

    Moidunny Shamsudheen

    2012-08-01

    Full Text Available Abstract Background Neuroprotective and neurotrophic properties of leukemia inhibitory factor (LIF have been widely reported. In the central nervous system (CNS, astrocytes are the major source for LIF, expression of which is enhanced following disturbances leading to neuronal damage. How astrocytic LIF expression is regulated, however, has remained an unanswered question. Since neuronal stress is associated with production of extracellular adenosine, we investigated whether LIF expression in astrocytes was mediated through adenosine receptor signaling. Methods Mouse cortical neuronal and astrocyte cultures from wild-type and adenosine A2B receptor knock-out animals, as well as adenosine receptor agonists/antagonists and various enzymatic inhibitors, were used to study LIF expression and release in astrocytes. When needed, a one-way analysis of variance (ANOVA followed by Bonferroni post-hoc test was used for statistical analysis. Results We show here that glutamate-stressed cortical neurons induce LIF expression through activation of adenosine A2B receptor subtype in cultured astrocytes and require signaling of protein kinase C (PKC, mitogen-activated protein kinases (MAPKs: p38 and ERK1/2, and the nuclear transcription factor (NF-κB. Moreover, LIF concentration in the supernatant in response to 5′-N-ethylcarboxamide (NECA stimulation was directly correlated to de novo protein synthesis, suggesting that LIF release did not occur through a regulated release pathway. Immunocytochemistry experiments show that LIF-containing vesicles co-localize with clathrin and Rab11, but not with pHogrin, Chromogranin (CgA and CgB, suggesting that LIF might be secreted through recycling endosomes. We further show that pre-treatment with supernatants from NECA-treated astrocytes increased survival of cultured cortical neurons against glutamate, which was absent when the supernatants were pre-treated with an anti-LIF neutralizing antibody. Conclusions

  13. Increased GABA(A receptor ε-subunit expression on ventral respiratory column neurons protects breathing during pregnancy.

    Directory of Open Access Journals (Sweden)

    Keith B Hengen

    Full Text Available GABAergic signaling is essential for proper respiratory function. Potentiation of this signaling with allosteric modulators such as anesthetics, barbiturates, and neurosteroids can lead to respiratory arrest. Paradoxically, pregnant animals continue to breathe normally despite nearly 100-fold increases in circulating neurosteroids. ε subunit-containing GABA(ARs are insensitive to positive allosteric modulation, thus we hypothesized that pregnant rats increase ε subunit-containing GABA(AR expression on brainstem neurons of the ventral respiratory column (VRC. In vivo, pregnancy rendered respiratory motor output insensitive to otherwise lethal doses of pentobarbital, a barbiturate previously used to categorize the ε subunit. Using electrode array recordings in vitro, we demonstrated that putative respiratory neurons of the preBötzinger Complex (preBötC were also rendered insensitive to the effects of pentobarbital during pregnancy, but unit activity in the VRC was rapidly inhibited by the GABA(AR agonist, muscimol. VRC unit activity from virgin and post-partum females was potently inhibited by both pentobarbital and muscimol. Brainstem ε subunit mRNA and protein levels were increased in pregnant rats, and GABA(AR ε subunit expression co-localized with a marker of rhythm generating neurons (neurokinin 1 receptors in the preBötC. These data support the hypothesis that pregnancy renders respiratory motor output and respiratory neuron activity insensitive to barbiturates, most likely via increased ε subunit-containing GABA(AR expression on respiratory rhythm-generating neurons. Increased ε subunit expression may be critical to preserve respiratory function (and life despite increased neurosteroid levels during pregnancy.

  14. Canonical Wnt signaling protects hippocampal neurons from Aβ oligomers: role of non-canonical Wnt-5a/Ca2+ in mitochondrial dynamics

    Science.gov (United States)

    Silva-Alvarez, Carmen; Arrázola, Macarena S.; Godoy, Juan A.; Ordenes, Daniela; Inestrosa, Nibaldo C.

    2013-01-01

    Alzheimer's disease (AD) is the most common type of age-related dementia. The disease is characterized by a progressive loss of cognitive abilities, severe neurodegeneration, synaptic loss and mitochondrial dysfunction. The Wnt signaling pathway participates in the development of the central nervous system and growing evidence indicates that Wnts also regulate the function of the adult nervous system. We report here, that indirect activation of canonical Wnt/β-catenin signaling using Bromoindirubin-30-Oxime (6-BIO), an inhibitor of glycogen synthase kinase-3β, protects hippocampal neurons from amyloid-β (Aβ) oligomers with the concomitant blockade of neuronal apoptosis. More importantly, activation with Wnt-5a, a non-canonical Wnt ligand, results in the modulation of mitochondrial dynamics, preventing the changes induced by Aβ oligomers (Aβo) in mitochondrial fission-fusion dynamics and modulates Bcl-2 increases induced by oligomers. The canonical Wnt-3a ligand neither the secreted Frizzled-Related Protein (sFRP), a Wnt scavenger, did not prevent these effects. In contrast, some of the Aβ oligomer effects were blocked by Ryanodine. We conclude that canonical Wnt/β-catenin signaling controls neuronal survival, and that non-canonical Wnt/Ca2+signaling modulates mitochondrial dysfunction. Since mitochondrial dysfunction is present in neurodegenerative diseases, the therapeutic possibilities of the activation of Wnt signaling are evident. PMID:23805073

  15. Ferulic acid antioxidant protection against hydroxyl and peroxyl radical oxidation in synaptosomal and neuronal cell culture systems in vitro: structure-activity studies.

    Science.gov (United States)

    Kanski, Jaroslaw; Aksenova, Marina; Stoyanova, Antonia; Butterfield, D Allan

    2002-05-01

    In this study, free radical scavenging abilities of ferulic acid in relation to its structural characteristics were evaluated in solution, cultured neurons, and synaptosomal systems exposed to hydroxyl and peroxyl radicals. Cultured neuronal cells exposed to the peroxyl radical initiator AAPH die in a dose-response manner and show elevated levels of protein carbonyls. The presence of ferulic acid or similar phenolic compounds, however, greatly reduces free radical damage in neuronal cell systems without causing cell death by themselves. In addition, synaptosomal membrane systems exposed to oxidative stress by hydroxyl and peroxyl radical generators show elevated levels of oxidation as indexed by protein oxidation, lipid peroxidation, and ROS measurement. Ferulic acid greatly attenuates these changes, and its effects are far more potent than those obtained for vanillic, coumaric, and cinnamic acid treatments. Moreover, ferulic acid protects against free radical mediated changes in conformation of synaptosomal membrane proteins as monitored by EPR spin labeling techniques. The results presented in this study suggest the importance of naturally occurring antioxidants such as ferulic acid in therapeutic intervention methodology against neurodegenerative disorders such as Alzheimer's disease in which oxidative stress is implicated.

  16. miR-7 and miR-153 protect neurons against MPP+- induced cell death via upregulation of mTOR pathway

    Directory of Open Access Journals (Sweden)

    Apostolia eFragkouli

    2014-07-01

    Full Text Available Differential expression of microRNAs (miRs in the brain of patients with neurodegenerative diseases suggests that they may have key regulatory roles in the development of these disorders. Two such miRs, miR-7 and miR-153 have recently been shown to target α-synuclein, a protein critically involved in the pathological process of Parkinson’s disease. By using a well-established in culture Parkinson’s disease model that of neurotoxin 1-Methyl-4-Phenyl-Pyridinium (MPP+, we examined whether miR-7 and miR-153 display neuroprotective properties. Herein, we demonstrate that treatment of cortical neurons with MPP+ induced a dose-dependent cell death with apoptotic characteristics. This was reflected in altered intracellular signaling characterized by increased levels of activated kinases p38MAPK and ERK1/2 and reduced levels of activated AKT, p70S6K and SAPK/JNK. Overexpression of miR-7 or miR-153 by adenoviral transduction protected cortical neurons from MPP+-induced toxicity, restored neuronal viability and anti-apoptotic BCL-2 protein levels while attenuated activation of caspase-3. Moreover, both miR-7 and miR-153 interfered with MPP+-induced alterations in intracellular signaling pathways in a partially overlapping manner; specifically, they preserved activation of mTOR and SAPK/JNK signaling pathways in the MPP+-treated neurons, while miR-153 also attenuated MPP+-induced activation of p38MAPK. No major effects were observed in the rest of signaling cascades or proteins investigated. Furthermore, the neuroprotective effect of miR-7 and miR-153 was alleviated when MPP+ was co-administered with rapamycin. Taken together, our results suggest that miR-7 and miR-153 protect neurons from cell death by interfering with the MPP+-induced downregulation of mTOR signaling.

  17. Protective effects of a polysaccharide from Spirulina platensis on dopaminergic neurons in an MPTP-induced Parkinson's disease model in C57BL/6J mice

    Science.gov (United States)

    Zhang, Fang; Lu, Jian; Zhang, Ji-guo; Xie, Jun-xia

    2015-01-01

    The present study aimed to determine whether a polysaccharide obtained from Spirulina platensis shows protective effects on dopaminergic neurons. A Parkinson's disease model was established through the intraperitoneal injection of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) in C57BL/6J mice. Prior to the MPTP injection, some mice were pretreated with intraperitoneal injections of a polysaccharide derived from Spirulina platensis once daily for 10 days. The results showed that the immunoreactive staining and mRNA expression of the dopamine transporter and tyrosine hydroxylase, the rate-limiting enzyme in dopamine synthesis, in the substantia nigra, were significantly increased in mice pretreated with 800 mg/kg of the polysaccharide compared with those in MPTP-treated mice. The activities of superoxide dismutase and glutathione peroxidase in the serum and midbrain were also increased significantly in mice injected with MPTP after pretreatment with the polysaccharide from Spirulina platensis. By contrast, the activity of monoamine oxidase B in serum and midbrain maintained unchanged. These experimental findings indicate that the polysaccharide obtained from Spirulina platensis plays a protective role against the MPTP-induced loss of dopaminergic neurons in C57BL/6J mice, and that the antioxidative properties of this polysaccharide likely underlie its neuroprotective effect. PMID:25883632

  18. 黄豆苷元神经保护作用研究进展%Research Progress in Neuronal Protection Mechanisms of Daidzein

    Institute of Scientific and Technical Information of China (English)

    周丽; 张永忠

    2012-01-01

    Daidzein is an isoflavone in an aglycone form. It has a series of biological activities. The animal experiments, clinical researches and epidemiological investigations indicated that daidzein has multiple functions for preventing and treating menopausal symptom, osteoporosis, breast cancer, prostate cancer and other diseases. More attentions have been paid to its capability for neuronal protection. In this paper, the functions and the neuronal protection mechanisms of daidzein have been discussed.%黄豆苷元是大豆异黄酮的3种苷元中的一种,具有多种生物学活性。动物实验、临床研究及流行病学调查表明黄豆苷元对更年期综合症、骨质疏松、乳腺癌、前列腺癌等具有防治作用。近来黄豆苷元的神经保护作用也日益受到重视。故本文对黄豆苷元神经保护方面的作用及其机理进行综述。

  19. Protective effects of a polysaccharide from Spirulina platensis on dopaminergic neurons in an MPTP-induced Parkinson′s disease model in C57BL/6J mice

    Directory of Open Access Journals (Sweden)

    Fang Zhang

    2015-01-01

    Full Text Available The present study aimed to determine whether a polysaccharide obtained from Spirulina platensis shows protective effects on dopaminergic neurons. A Parkinson′s disease model was established through the intraperitoneal injection of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP in C57BL/6J mice. Prior to the MPTP injection, some mice were pretreated with intraperitoneal injections of a polysaccharide derived from Spirulina platensis once daily for 10 days. The results showed that the immunoreactive staining and mRNA expression of the dopamine transporter and tyrosine hydroxylase, the rate-limiting enzyme in dopamine synthesis, in the substantia nigra, were significantly increased in mice pretreated with 800 mg/kg of the polysaccharide compared with those in MPTP-treated mice. The activities of superoxide dismutase and glutathione peroxidase in the serum and midbrain were also increased significantly in mice injected with MPTP after pretreatment with the polysaccharide from Spirulina platensis. By contrast, the activity of monoamine oxidase B in serum and midbrain maintained unchanged. These experimental findings indicate that the polysaccharide obtained from Spirulina platensis plays a protective role against the MPTP-induced loss of dopaminergic neurons in C57BL/6J mice, and that the antioxidative properties of this polysaccharide likely underlie its neuroprotective effect.

  20. S-allyl cysteine activates the Nrf2-dependent antioxidant response and protects neurons against ischemic injury in vitro and in vivo.

    Science.gov (United States)

    Shi, Huanying; Jing, Xu; Wei, Xinbing; Perez, Ruth G; Ren, Manru; Zhang, Xiumei; Lou, Haiyan

    2015-04-01

    Stroke is a devastating clinical condition for which an effective neuroprotective treatment is currently unavailable. S-allyl cysteine (SAC), the most abundant organosulfur compound in aged garlic extract, has been reported to possess neuroprotective effects against stroke. However, the mechanisms underlying its beneficial effects remain poorly defined. The present study tests the hypothesis that SAC attenuates ischemic neuronal injury by activating the nuclear factor erythroid-2-related factor 2 (Nrf2)-dependent antioxidant response in both in vitro and in vivo models. Our findings demonstrate that SAC treatment resulted in an increase in Nrf2 protein levels and subsequent activation of antioxidant response element pathway genes in primary cultured neurons and mice. Exposure of primary neurons to SAC provided protection against oxygen and glucose deprivation-induced oxidative insults. In wild-type (Nrf2(+/+) ) mice, systemic administration of SAC attenuated middle cerebral artery occlusion-induced ischemic damage, a protective effect not observed in Nrf2 knockout (Nrf2(-/-) ) mice. Taken together, these findings provide the first evidence that activation of the Nrf2 antioxidant response by SAC is strongly associated with its neuroprotective effects against experimental stroke and suggest that targeting the Nrf2 pathway may provide therapeutic benefit for the treatment of stroke. The transcription factor Nrf2 is involved in cerebral ischemic disease and may be a promising target for the treatment of stroke. We provide novel evidence that SAC confers neuroprotection against ischemic stroke by activating the antioxidant Nrf2 signaling pathway. ARE, antioxidant response element; GCLC, glutathione cysteine ligase regulatory subunit; GCLM, glutathione cysteine ligase modulatory subunit; HO-1, heme oxygenase-1; JNK, c-Jun N-terminal kinase; Keap1, Kelch-like ECH-associated protein 1; Maf, musculoaponeurotic fibrosarcoma; Nrf2, nuclear factor erythroid-2-related factor 2

  1. High-throughput functional genomics identifies genes that ameliorate toxicity due to oxidative stress in neuronal HT-22 cells: GFPT2 protects cells against peroxide.

    Science.gov (United States)

    Zitzler, Jürgen; Link, Dieter; Schäfer, Rolf; Liebetrau, Wolfgang; Kazinski, Michael; Bonin-Debs, Angelika; Behl, Christian; Buckel, Peter; Brinkmann, Ulrich

    2004-08-01

    We describe a novel genetic screen that is performed by transfecting every individual clone of an expression clone collection into a separate population of cells in a high-throughput mode. We combined high-throughput functional genomics with experimental validation to discover human genes that ameliorate cytotoxic responses of neuronal HT-22 cells upon exposure to oxidative stress. A collection of 5,000 human cDNAs in mammalian expression vectors were individually transfected into HT-22 cells, which were then exposed to H(2)O(2). Five genes were found that are known to be involved in pathways of detoxification of peroxide (catalase, glutathione peroxidase-1, peroxiredoxin-1, peroxiredoxin-5, and nuclear factor erythroid-derived 2-like 2). The presence of those genes in our "hit list" validates our screening platform. In addition, a set of candidate genes was found that has not been previously described as involved in detoxification of peroxide. One of these genes, which was consistently found to reduce H(2)O(2) -induced toxicity in HT-22, was GFPT2. This gene is expressed at significant levels in the central nervous system (CNS) and encodes glutamine-fructose-6-phosphate transaminase (GFPT) 2, a rate-limiting enzyme in hexosamine biosynthesis. GFPT has recently also been shown to ameliorate the toxicity of methylmercury in Saccharomyces cerevisiae. Methylmercury causes neuronal cell death in part by protein modification as well as enhancing the production of reactive oxygen species (ROS). The protective effect of GFPT2 against H(2)O(2) toxicity in neuronal HT-22 cells may be similar to its protection against methylmercury in yeast. Thus, GFPT appears to be conserved among yeast and men as a critical target of methylmercury and ROS-induced cytotoxicity.

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

    Science.gov (United States)

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

    2013-09-01

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

  3. Daucosterol protects neurons against oxygen-glucose deprivation/reperfusion-mediated injury by activating IGF1 signaling pathway.

    Science.gov (United States)

    Jiang, Li-hua; Yuan, Xiao-lin; Yang, Nian-yun; Ren, Li; Zhao, Feng-ming; Luo, Ban-xin; Bian, Yao-yao; Xu, Jian-ya; Lu, Da-xiang; Zheng, Yuan-yuan; Zhang, Chuan-juan; Diao, Yuan-ming; Xia, Bao-mei; Chen, Gang

    2015-08-01

    We previously reported that daucosterol (a sterolin) up-regulates the expression of insulin-like growth factor I (IGF1)(1) protein in neural stem cells. In this study, we investigated the effects of daucosterol on the survival of cultured cortical neurons after neurons were subjected to oxygen and glucose deprivation and simulated reperfusion (OGD/R)(2), and determined the corresponding molecular mechanism. The results showed that post-treatment of daucosterol significantly reduced neuronal loss, as well as apoptotic rate and caspase-3 activity, displaying the neuroprotective activity. We also found that daucosterol increased the expression level of IGF1 protein, diminished the down-regulation of p-AKT(3) and p-GSK-3β(4), thus activating the AKT(5) signal pathway. Additionally, it diminished the down-regulation of the anti-apoptotic proteins Mcl-1(6) and Bcl-2(7), and decreased the expression level of the pro-apoptotic protein Bax(8), thus raising the ratio of Bcl-2/Bax. The neuroprotective effect of daucosterol was inhibited in the presence of picropodophyllin (PPP)(9), the inhibitor of insulin-like growth factor I receptors (IGF1R)(10). Our study provided information about daucosterol as an efficient and inexpensive neuroprotectants, to which the IGF1-like activity of daucosterol contributes. Daucosterol could be potentially developed as a medicine for ischemic stroke treatment.

  4. δ-opioid receptors protect neurons against neuronal injury induced by oxygen-glucose deprivation%激活δ-阿片受体可对抗原代培养神经元氧糖剥夺损伤

    Institute of Scientific and Technical Information of China (English)

    李名伟; 朱敏; 田雪松; 区晓敏; 夏萤; 郭景春

    2009-01-01

    Objective To investigate the effect of cortical 8-opioid receptor (DOR) on oxygen-glucose deprivation-induced (OGD-induced) neuronal injury. Methods Primary cultured cortical neurons incubated with selective DOR agonist (TAN-67) and antagonist (naltrindole) or PKC inhibitor (chelerythrine, CHE) were exposed to OGD. Lactate dehydrogenase (LDH) release was detected after 24 h reperfusion. The expression levels of DOR were measured by Western blot. Results Compared with OGD group, TAN-67 significantly decreased OGD-indueed LDH release, and increased the expression levels of DOR, while nahrindole aggravated neuronal injury and decreased the DOR protein expression. CHE could abolish the LDH down-regulation induced by TAN-67 plus OGD (P< 0.05, compared with TAN-67 treated group). Conclusions DOR activation protects neurons against OGD injury. PKC might take part in the neuroprotection pathways of DOR.%目的 研究皮层δ-阿片受体(δ-opioid receptor,DOR)的抗神经元氧糖剥夺损伤作用.方法 采用原代培养胎鼠皮层神经元氧糖剥夺(oxygen-glucose deprivation,OGD)模型,分别加入DOR选择性激动剂TAN一67、拮抗剂nahrindole及PKC抑制剂chelerythrine(CHE),检测再灌注后培液中LDH水平、进行死/活细胞染色,并利用Western blot检测再灌注24 h后DOR蛋白表达水平.结果 与单纯OGD组相比,OGD+TAN-67组培液中的LDH水平明显下降,荧光染色显示活细胞增加死细胞减少,且DOR蛋白表达增加;OGD+naltrindole组则细胞受损加重.且DOR蛋白表达减少.PKC抑制剂CHE能抑制DOR激活后培液中LDH水平的下调.结论 DOR激动剂可以抗神经元氧糖剥夺损伤.拮抗DOR则加重该损伤.PKC可能参与了DOR的神经保护作用.

  5. 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 (P<0.05). These findings suggest that PostC inhibited OGD-induced neuron death. This neuro-protective effect is likely achieved by anti-apoptotic mechanisms and is associated with over-expression of HSP70.

  6. Protection of HT22 neuronal cells against glutamate toxicity mediated by the antioxidant activity of Pueraria candollei var. mirifica extracts.

    Science.gov (United States)

    Sucontphunt, Apirada; De-Eknamkul, Wanchai; Nimmannit, Ubonthip; Dan Dimitrijevich, S; Gracy, Robert W

    2011-01-01

    Neuronal degeneration is known to be due to oxidative stress acting through a pathway involving the excessive activation of glutamate receptors. We studied the neuroprotection potential of an ethyl acetate-ethanol extract of Pueraria mirifica (P. candollei var. mirifica) root (PM extract). PM extract was evaluated for its antioxidant and neuroprotective activities against glutamate toxicity in mouse hippocampal HT22 neuronal cells. The extract at concentrations of 10 and 50 μg/ml exhibited considerable antioxidant activity with significant neuroprotection, based on the microscopic observations of cell morphology and the determination of cell viability and cell number. Studies of the possible mechanisms of action indicated that the neuroprotection exerted by PM extract was related to its scavenging activity against H(2)O(2) and related reactive oxygen species. High-performance liquid chromatography (HPLC) and thin-layer chromatography (TLC) analyses showed that the extract contained daidzein and genistein as identified constituents, as well as additional components with antioxidant activity. While daidzein and genistein individually and in combination were observed not to be neuroprotective, we propose that the antioxidant and neuroprotective activities of PM extract are derived from the combined properties of its constituents.

  7. Point application withAngong Niuhuang sticker protects hippocampal and cortical neurons in rats with cerebral ischemia

    Institute of Scientific and Technical Information of China (English)

    Dong-shu Zhang; Yuan-liang Liu; Dao-qi Zhu; Xiao-jing Huang; Chao-hua Luo

    2015-01-01

    Angong Niuhuang pill, a Chinese materia medica preparation, can improve neurological func-tions after acute ischemic stroke. Because of its inconvenient application and toxic components (Cinnabaris andRealgar), we used transdermal enhancers to deliverAngong Niuhuang pill by modern technology, which expanded the safe dose range and clinical indications. In this study, Angong Niuhuang stickers administered at different point application doses (1.35, 2.7, and 5.4 g/kg) were administered to theDazhui (DU14), Qihai(RN6) andMingmen (DU4) of rats with chronic cerebral ischemia, for 4 weeks. The Morris water maze was used to determine the learning and memory ability of rats. Hematoxylin-eosin staining and Nissl staining were used to observe neuronal damage of the cortex and hippocampal CA1 region in rats with chronic cerebral ischemia. The middle- and high-dose point application ofAngong Niuhuangstickers attenuated neuronal damage in the cortex and hippocampal CA1 region, and improved the memory of rats with chronic cerebral ischemia with an efifcacy similar to interventions by electroacupuncture at Dazhui (DU14),Qihai (RN6) andMingmen (DU4). Our experimental ifndings indicate that point application withAngong Niuhuang stickers can improve cognitive function after chronic cerebral ischemia in rats and is neuroprotective with an equivalent efifcacy to acupuncture.

  8. Human Adipose Tissue Conditioned Media from Lean Subjects Is Protective against H2O2 Induced Neurotoxicity in Human SH-SY5Y Neuronal Cells

    Directory of Open Access Journals (Sweden)

    Zhongxiao Wan

    2015-01-01

    Full Text Available Adipose tissue secretes numerous hormone-like factors, which are known as adipokines. Adipokine receptors have been identified in the central nervous system but the potential role of adipokine signaling in neuroprotection is unclear. The aim of this study is to determine (1 Whether adipokines secreted from cultured adipose tissue of lean humans is protective against oxidative stress-induced neurotoxicity in human SH-SY5Y neuronal cells; and (2 To explore potential signaling pathways involved in these processes. Adipose tissue conditioned media (ATCM from healthy lean subjects completely prevented H2O2 induced neurotoxicity, while this effect is lost after heating ATCM. ATCM activated the phosphorylation of ERK1/2, JNK and Akt at serine 308 in SH-SY5Y cells. PD98059 (25 µM, SP600125 (5 µM and LY29400 (20 µM partially blocked the protective effects of ATCM against H2O2 induced neurotoxicity. Findings demonstrate that heat-sensitive factors secreted from human adipose tissue of lean subjects are protective against H2O2 induced neurotoxicity and ERK1/2, JNK, and PI3K signaling pathways are involved in these processes. In conclusion, this study demonstrates preliminary but encouraging data to further support that adipose tissue secreted factors from lean human subjects might possess neuroprotective properties and unravel the specific roles of ERK1/2, JNK and PI3K in these processes.

  9. Experimental Cancer Cachexia Changes Neuron Numbers and Peptide Levels in the Intestine: Partial Protective Effects after Dietary Supplementation with L-Glutamine

    Science.gov (United States)

    Vicentini, Geraldo E.; Fracaro, Luciane; de Souza, Sara R. G.; Martins, Heber A.; Guarnier, Flávia A.; Zanoni, Jacqueline N.

    2016-01-01

    Gastrointestinal dysmotility frequently occurs in cancer cachexia and may result from damage to enteric innervation caused by oxidative stress, especially due to glutathione depletion. We assessed the effect of dietary supplementation with 20 g/kg l-glutamine (a glutathione precursor) on the intrinsic innervation of the enteric nervous system in healthy and Walker 256 tumor-bearing Wistar rats during the development of experimental cachexia (14 days), in comparison with non-supplemented rats, by using immunohistochemical methods and Western blotting. The total neural population and cholinergic subpopulation densities in the myenteric plexus, as well as the total population and VIPergic subpopulation in the submucosal plexus of the jejunum and ileum, were reduced in cachectic rats, resulting in adaptive morphometric alterations and an increase in vasoactive intestinal peptide (VIP) and calcitonin gene-related peptide (CGRP) expression, suggesting a neuroplastic response. l-glutamine supplementation prevented decrease in myenteric neuronal density in the ileum, morphometric alterations in the neurons and nerve fibers (in both the plexuses of the jejunum and ileum), and the overexpression of VIP and CGRP. Cancer cachexia severely affected the intrinsic innervation of the jejunum and ileum to various degrees and this injury seems to be associated with adaptive neural plasticity. l-glutamine supplementation presented partial protective effects on the enteric innervation against cancer cachexia, possibly by attenuating oxidative stress. PMID:27635657

  10. Phosphatidylinositol 3-kinase/Akt signaling pathway mediates acupuncture-induced dopaminergic neuron protection and motor function improvement in a mouse model of Parkinson's disease.

    Science.gov (United States)

    Kim, Seung-Nam; Kim, Seung-Tae; Doo, Ah-Reum; Park, Ji-Yeun; Moon, Woongjoon; Chae, Younbyoung; Yin, Chang Shik; Lee, Hyejung; Park, Hi-Joon

    2011-10-01

    It has been reported that acupuncture treatment reduced dopaminergic neuron degeneration in Parkinson's disease (PD) models. However, the mechanistic pathways underlying, such neuroprotection, are poorly understood. Here, we investigated the effects and the underlying mechanism of acupuncture in a mouse model of PD using 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). First, we observed that MPTP-induced impairment of Akt activation, but not MPTP-induced c-Jun activation, was effectively restored by acupuncture treatment in the substantia nigra. Furthermore, we demonstrated for the first time that the brain-specific blockade of phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathway, by intranasal administration of LY294002, a specific inhibitor of PI3K/Akt signaling pathway, significantly blocked acupuncture-induced dopaminergic neuron protection and motor function improvement. Our results provide evidence that PI3K/Akt signaling pathway may play a central role in the mechanism underlying acupuncture-induced benefits in Parkinsonian mice.

  11. Expression of the neuronal adaptor protein X11alpha protects against memory dysfunction in a transgenic mouse model of Alzheimer's disease.

    LENUS (Irish Health Repository)

    Mitchell, Jacqueline C

    2010-01-01

    X11alpha is a neuronal-specific adaptor protein that binds to the amyloid-beta protein precursor (AbetaPP). Overexpression of X11alpha reduces Abeta production but whether X11alpha also protects against Abeta-related memory dysfunction is not known. To test this possibility, we crossed X11alpha transgenic mice with AbetaPP-Tg2576 mice. AbetaPP-Tg2576 mice produce high levels of brain Abeta and develop age-related defects in memory function that correlate with increasing Abeta load. Overexpression of X11alpha alone had no detectable adverse effect upon behavior. However, X11alpha reduced brain Abeta levels and corrected spatial reference memory defects in aged X11alpha\\/AbetaPP double transgenics. Thus, X11alpha may be a therapeutic target for Alzheimer\\'s disease.

  12. Early Cellular Responses of Purine Nucleoside-mediated Protection of Hypoxia-induced Injuries of Neuronal PC12 Cells

    Directory of Open Access Journals (Sweden)

    Bettina Tomaselli

    2005-01-01

    Full Text Available Hypoxia in brain may lead to cell death by apoptosis and necrosis. In parallel adenosine, a powerful endogenous neuroprotectant is formed. We wanted to investigate the effect of adenosine and its purine nucleoside relatives, inosine and guanosine on early cellular responses to hypoxia. O2-sensitive neuronal PC12-cells were subjected to chemical hypoxia induced with rotenone, an inhibitor of mitochondrial complex I. Loss of viability after hypoxic insult was impressively rescued by adenosine, guanosine and inosine. PC12-cells mainly express the A2A adenosine receptor. Its inhibition with a specific antagonist (CSC induced cell death of PC12-cells, which could be salvaged by adenosine but not with guanosine or inosine. We have previously demonstrated the important role of mitogen activated protein kinases 1/2 (p42/44 MAPK in purine-mediated rescue. In this study we were interested in the involvement of protein kinases whose activities mediate these processes, including protein kinase A (PKA, phosphoinositide 3-kinase (PI3-K and protein kinase C-related kinases (PRK 1/2. Pharmacological inhibition of PKA and PI3-K increased hypoxia-induced toxicity and likewise also affected the rescue by purine nucleosides. Nerve growth factor (NGF and purine nucleosides induced an activation of PRK 1/2, which to our knowledge indicates for the first time that these kinases are potentially involved in purine nucleoside-mediated rescue of hypoxic neuronal cells. Results suggest that A2A receptor expressing cells are mainly dependent on the purine nucleoside adenosine for their rescue after hypoxic insult. In addition to PKA, PI3-K is an important effector molecule in A2A-mediated signaling and for the rescue of PC12-cells after hypoxic insult.

  13. Rapamycin protects against neuronal death and improves neurological function with modulation of microglia after experimental intracerebral hemorrhage in rats.

    Science.gov (United States)

    Li, D; Liu, F; Yang, T; Jin, T; Zhang, H; Luo, X; Wang, M

    2016-09-30

    Intracerebral hemorrhage (ICH) results in a devastating brain disorder with high mortality and poor prognosis and effective therapeutic intervention for the disease remains a challenge at present. The present study investigated the neuroprotective effects of rapamycin on ICH-induced brain damage and the possible involvement of activated microglia. ICH was induced in rats by injection of type IV collagenase into striatum. Different dose of rapamycin was systemically administrated by intraperitoneal injection beginning at 1 h after ICH induction. Western blot analysis showed that ICH led to a long-lasting increase of phosphorylated mTOR and this hyperactivation of mTOR was reduced by systemic administration of rapamycin. Rapamycin treatment significantly improved the sensorimotor deficits induced by ICH, and attenuated ICH-induced brain edema formation as well as lesion volume. Nissl and Fluoro-Jade C staining demonstrated that administration with rapamycin remarkably decreased neuronal death surrounding the hematoma at 7 d after ICH insult. ELISA and real-time quantitative PCR demonstrated that rapamycin inhibited ICH-induced excessive expression of TNF-α and IL-1β in ipsilateral hemisphere. Furthermore, activation of microglia induced by ICH was significantly suppressed by rapamycin administration. These data indicated that treatment of rapamycin following ICH decreased the brain injuries and neuronal death at the peri-hematoma striatum, and increased neurological function, which associated with reduced the levels of proinflammatory cytokines and activated microglia. The results provide novel insight into the neuroprotective therapeutic strategy of rapamycin for ICH insult, which possibly involving the regulation of microglial activation.

  14. Protective effect of atmospheric pressure plasma on oxidative stress-induced neuronal injuries: an in vitro study

    Science.gov (United States)

    Yan, Xu; Qiao, Yajun; Ouyang, Jiting; Jia, Mei; Li, Jiaxin; Yuan, Fang

    2017-03-01

    Atmospheric pressure plasma jet (APPJ) can produce biological active species for biomedical applications. This work proves direct evidence of the protective effects of APPJ against oxidative stress. SH-SY5Y cells, a commonly used cell model for the study of neurotoxicity and neuroprotection, were treated with APPJ for different durations. Then, cells were exposed to 200 µM H2O2 for 24 h and cell viability was measured using a CCK-8 kit. Changes in cell apoptosis were further confirmed by calcein-AM fluorescence imaging and flow cytometry. Extracellular NO production was detected using the Griess method. The results showed that APPJ protected SH-SY5Y from H2O2-induced apoptosis in a time-dependent manner. Moreover, extracellular NO production was significantly increased with the APPJ treatment. The results show in vitro that APPJ treatment could protect SH-SY5Y cells from oxidative stress by reducing cell apoptosis, which might be related to the reactive nitrogen species induced by the APPJ treatment. Our results indicate that the APPJ may have therapeutic potential as a novel ‘NO donor drug’ in neuroprotection and in the treatment of neurodegenerative diseases.

  15. PEG-PEI/siROCK2 Protects Against Aβ42-Induced Neurotoxicity in Primary Neuron Cells for Alzheimer Disease.

    Science.gov (United States)

    Liu, Yunyun; Yang, Xingyi; Lei, Qingfeng; Li, Zhong; Hu, Jingyang; Wen, Xiaojun; Wang, Huijun; Liu, Zhonglin

    2015-08-01

    Gene therapy that targets the ROCK2 gene has yielded promising results in the treatment of AD. Our previous study indicated that PEG-PEI/siROCK2 could effectively suppress ROCK2 mRNA expression and showed a promising prospect for the treatment of Alzheimer's disease. However, the ability of PEG-PEI/siROCK2 to reduce Aβ-induced cytotoxicity is unknown. To investigate the effect of PEG-PEI/siROCK2 against Aβ42-induced neurotoxicity, primary cultured cortical neurons were pretreated with PEG-PEI/siROCK2 for 24 h and then treated with 5 μM Aβ42 for 24 h. We found that PEG-PEI/siROCK2 increased the cell viability and reduced the number of apoptotic cells induced by Aβ42, as measured using an MTT assay and Annexin V/PI staining. A further study revealed that PEG-PEI/siROCK2 can activate p-Akt, and treatment with the PI3K inhibitor LY294002 attenuated the neuroprotective effects. These results suggest that PEG-PEI/siROCK2 prevents Aβ42-induced neurotoxicity and that the activation of PI3K/Akt pathway is involved in neuroprotection. Taken together, these findings shed light on the role of PEG-PEI/siROCK2 as a potential therapeutic agent for AD.

  16. Methylene blue induces macroautophagy through 5' adenosine monophosphate-activated protein kinase pathway to protect neurons from serum deprivation.

    Science.gov (United States)

    Xie, Luokun; Li, Wenjun; Winters, Ali; Yuan, Fang; Jin, Kunlin; Yang, Shaohua

    2013-01-01

    Methylene blue has been shown to be neuroprotective in multiple experimental neurodegenerative disease models. However, the mechanisms underlying the neuroprotective effects have not been fully elucidated. Previous studies have shown that macroautophagy has multiple beneficial roles for maintaining normal cellular homeostasis and that induction of macroautophagy after myocardial ischemia is protective. In the present study we demonstrated that methylene blue could protect HT22 hippocampal cell death induced by serum deprivation, companied by induction of macroautophagy. We also found that methylene blue-mediated neuroprotection was abolished by macroautophagy inhibition. Interestingly, 5' adenosine monophosphate-activated protein kinase (AMPK) signaling, but not inhibition of mammalian target of rapamycin signaling, was activated at 12 and 24 h after methylene blue treatment in a dose-dependent manner. Methylene blue-induced macroautophagy was blocked by AMPK inhibitor. Consistent with in vitro data, macroautophagy was induced in the cortex and hippocampus of mouse brains treated with methylene blue. Our findings suggest that methylene blue-induced neuroprotection is mediated, at least in part, by macroautophagy though activation of AMPK signaling.

  17. Rutin protects against neuronal damage in vitro and ameliorates doxorubicin-induced memory deficits in vivo in Wistar rats

    Directory of Open Access Journals (Sweden)

    Ramalingayya GV

    2017-03-01

    Full Text Available Grandhi Venkata Ramalingayya, Sri Pragnya Cheruku, Pawan G Nayak, Anoop Kishore, Rekha Shenoy, Chamallamudi Mallikarjuna Rao, Nandakumar Krishnadas Department of Pharmacology, Manipal College of Pharmaceutical Sciences, Manipal University, Manipal, Karnataka, India Abstract: Doxorubicin (DOX is the most widely used broad-spectrum anticancer agent, either alone or in combination, for most cancers including breast cancer. Long-term use of chemotherapeutic agents to treat breast cancer patients results in cognitive complications with a negative impact on survivors’ quality of life. The study objective was to evaluate rutin (RUT for its neuroprotective effect against DOX in human neuroblastoma (IMR32 cells in vitro and study its potential to ameliorate DOX-induced cognitive dysfunction in Wistar rats. Cell viability assay (3-[4,5 dimethyl thiazol-2-yl]-2,5-diphenyl tetrazolium bromide, neurite growth assay, detection of apoptosis by (acridine orange/ethidium bromide staining, intracellular reactive oxygen species (ROS assay, and flowcytometric analysis were carried out to assess neuroprotective potential against DOX. An in vivo study was conducted for assessing protective effect of RUT against memory deficit associated with DOX-induced chemobrain using object recognition task (ORT. Locomotion was assessed using open field test. Serum biochemistry, acetylcholinesterase, oxidative stress markers in hippocampus, and frontal cortex were assessed. Histopathological analysis of major organ systems was also carried out. Prior exposure to RUT at 100 µM protected IMR32 cells from DOX (1 µM neurotoxicity. DOX exposure resulted in increased cellular death, apoptosis, and intracellular ROS generation with inhibition of neurite growth in differentiated IMR32 cells, which was significantly ameliorated by RUT. Cognitive dysfunction was induced in Wistar rats by administering ten cycles of DOX (2.5 mg/kg, intraperitoneal, once in 5 days, as we observed

  18. Inhibition of aminoacylase 3 protects rat brain cortex neuronal cells from the toxicity of 4-hydroxy-2-nonenal mercapturate and 4-hydroxy-2-nonenal

    Energy Technology Data Exchange (ETDEWEB)

    Tsirulnikov, Kirill; Abuladze, Natalia [Department of Medicine, University of California at Los Angeles, CA 90095 (United States); Bragin, Anatol [Department of Neurology, University of California at Los Angeles, CA 90095 (United States); Brain Research Institute, University of California at Los Angeles, CA 90095 (United States); Faull, Kym [Brain Research Institute, University of California at Los Angeles, CA 90095 (United States); Department of Psychiatry and Biobehavioral Sciences, University of California at Los Angeles, CA 90095 (United States); Pasarow Mass Spectrometry Laboratory, University of California at Los Angeles, CA 90095 (United States); Cascio, Duilio [Institute of Genomics and Proteomics, University of California at Los Angeles, CA 90095 (United States); Damoiseaux, Robert; Schibler, Matthew J. [California NanoSystems Institute, University of California at Los Angeles, CA 90095 (United States); Pushkin, Alexander, E-mail: apushkin@mednet.ucla.edu [Department of Medicine, University of California at Los Angeles, CA 90095 (United States)

    2012-09-15

    4-Hydroxy-2-nonenal (4HNE) and acrolein (ACR) are highly reactive neurotoxic products of lipid peroxidation that are implicated in the pathogenesis and progression of Alzheimer's and Parkinson's diseases. Conjugation with glutathione (GSH) initiates the 4HNE and ACR detoxification pathway, which generates the mercapturates of 4HNE and ACR that can be excreted. Prior work has shown that the efficiency of the GSH-dependent renal detoxification of haloalkene derived mercapturates is significantly decreased upon their deacetylation because of rapid transformation of the deacetylated products into toxic compounds mediated by β-lyase. The enzymes of the GSH-conjugation pathway and β-lyases are expressed in the brain, and we hypothesized that a similar toxicity mechanism may be initiated in the brain by the deacetylation of 4HNE- and ACR-mercapturate. The present study was performed to identify an enzyme(s) involved in 4HNE- and ACR-mercapturate deacetylation, characterize the brain expression of this enzyme and determine whether its inhibition decreases 4HNE and 4HNE-mercapturate neurotoxicity. We demonstrated that of two candidate deacetylases, aminoacylases 1 (AA1) and 3 (AA3), only AA3 efficiently deacetylates both 4HNE- and ACR-mercapturate. AA3 was further localized to neurons and blood vessels. Using a small molecule screen we generated high-affinity AA3 inhibitors. Two of them completely protected rat brain cortex neurons expressing AA3 from the toxicity of 4HNE-mercapturate. 4HNE-cysteine (4HNE-Cys) was also neurotoxic and its toxicity was mostly prevented by a β-lyase inhibitor, aminooxyacetate. The results suggest that the AA3 mediated deacetylation of 4HNE-mercapturate may be involved in the neurotoxicity of 4HNE.

  19. FLZ protects dopaminergic neuron through activating protein kinase B/mammalian target of rapamycin pathway and inhibiting RTP801 expression in Parkinson's disease models.

    Science.gov (United States)

    Bao, X-Q; Kong, X-C; Qian, C; Zhang, D

    2012-01-27

    The pathogenesis of Parkinson's disease is characterized by progressive degeneration of dopaminergic neurons in substantia nigra (SNpc). FLZ, a novel synthetic squamosamide derivative from a Chinese herb, has been shown to have neuroprotective effects in experimental Parkinson's disease (PD) models. However, it is still unclear whether FLZ protects against PD through regulating the function of dopaminergic system. In this study, we carried out a set of in vitro and in vivo experiments to address these questions. Oral administration of FLZ significantly improved motor dysfunction of mice challenged by MPTP. The beneficial effects of FLZ on motor behavior attributed to the elevation of dopamine level in striatum, tyrosine hydroxylase (TH)-positive cells, and TH activity in the middle brain of mouse. Mechanism study showed that treatment of FLZ increased the phosphorylation of activating protein kinase B (Akt) and mammalian target of rapamycin (mTOR). Using LY294002 to block phosphoinositide 3-kinases (PI3K)/Akt signaling pathway prevented the phosphorylation of mTOR and attenuated the neuroprotection of FLZ in MN9D cells challenged by MPP(+). In addition, FLZ reduced the expression of RTP801, an important protein in PD, in mice and cells intoxicated by MPTP/MPP(+). Taken together, these results revealed a novel role that FLZ elevated TH expression and activity in dopaminergic neuron through activation of Akt/mTOR survival pathway and inhibition of RTP801 in MPTP/MPP(+)-induced PD models. The data also provided evidence that FLZ had potent neuroprotecive effects and might become a new promising anti-PD drug.

  20. Protective

    Directory of Open Access Journals (Sweden)

    Wessam M. Abdel-Wahab

    2013-10-01

    Full Text Available Many active ingredients extracted from herbal and medicinal plants are extensively studied for their beneficial effects. Antioxidant activity and free radical scavenging properties of thymoquinone (TQ have been reported. The present study evaluated the possible protective effects of TQ against the toxicity and oxidative stress of sodium fluoride (NaF in the liver of rats. Rats were divided into four groups, the first group served as the control group and was administered distilled water whereas the NaF group received NaF orally at a dose of 10 mg/kg for 4 weeks, TQ group was administered TQ orally at a dose of 10 mg/kg for 5 weeks, and the NaF-TQ group was first given TQ for 1 week and was secondly administered 10 mg/kg/day NaF in association with 10 mg/kg TQ for 4 weeks. Rats intoxicated with NaF showed a significant increase in lipid peroxidation whereas the level of reduced glutathione (GSH and the activity of superoxide dismutase (SOD, catalase (CAT, glutathione S-transferase (GST and glutathione peroxidase (GPx were reduced in hepatic tissues. The proper functioning of the liver was also disrupted as indicated by alterations in the measured liver function indices and biochemical parameters. TQ supplementation counteracted the NaF-induced hepatotoxicity probably due to its strong antioxidant activity. In conclusion, the results obtained clearly indicated the role of oxidative stress in the induction of NaF toxicity and suggested hepatoprotective effects of TQ against the toxicity of fluoride compounds.

  1. S-Glutathionylation of Keap1: a new role for glutathione S-transferase pi in neuronal protection.

    Science.gov (United States)

    Carvalho, Andreia Neves; Marques, Carla; Guedes, Rita C; Castro-Caldas, Margarida; Rodrigues, Elsa; van Horssen, Jack; Gama, Maria João

    2016-05-01

    Oxidative stress is a key pathological feature of Parkinson's disease (PD). Glutathione S-transferase pi (GSTP) is a neuroprotective antioxidant enzyme regulated at the transcriptional level by the antioxidant master regulator nuclear factor-erythroid 2-related factor 2 (Nrf2). Here, we show for the first time that upon MPTP-induced oxidative stress, GSTP potentiates S-glutathionylation of Kelch-like ECH-associated protein 1 (Keap1), an endogenous repressor of Nrf2, in vivo. S-glutathionylation of Keap1 leads to Nrf2 activation and subsequently increases expression of GSTP. This positive feedback regulatory loop represents a novel mechanism by which GSTP elicits antioxidant protection in the brain.

  2. Retinoic acids acting through retinoid receptors protect hippocampal neurons from oxygen-glucose deprivation-mediated cell death by inhibition of c-jun-N-terminal kinase and p38 mitogen-activated protein kinase.

    Science.gov (United States)

    Shinozaki, Y; Sato, Y; Koizumi, S; Ohno, Y; Nagao, T; Inoue, K

    2007-06-15

    Retinoic acids (RAs), including all-trans retinoic acid (ATRA) and 9-cis retinoic acid (9-cis RA), play fundamental roles in a variety of physiological events in vertebrates, through their specific nuclear receptors: retinoic acid receptor (RAR) and retinoid X receptor (RXR). Despite the physiological importance of RA, their functional significance under pathological conditions is not well understood. We examined the effect of ATRA on oxygen/glucose-deprivation/reperfusion (OGD/Rep)-induced neuronal damage in cultured rat hippocampal slices, and found that ATRA significantly reduced neuronal death. The cytoprotective effect of ATRA was observed not only in cornu ammonis (CA) 1 but also in CA2 and dentate gyrus (DG), and was attenuated by selective antagonists for RAR or RXR. By contrast, in the CA3 region, no protective effects of ATRA were observed. The OGD/Rep also increased phosphorylated forms of c-jun-N-terminal kinase (P-JNK) and p38 (P-p38) in hippocampus, and specific inhibitors for these kinases protected neurons. ATRA prevented the increases in P-JNK and P-p38 after OGD/Rep, as well as the decrease in NeuN and its shrinkage, all of which were inhibited by antagonists for RAR or RXR. These findings suggest that the ATRA signaling via retinoid receptors results in the inhibition of JNK and p38 activation, leading to the protection of neurons against OGD/Rep-induced damage in the rat hippocampus.

  3. A study on the mechanisms by which minocycline protects against MDMA ('ecstasy')-induced neurotoxicity of 5-HT cortical neurons.

    Science.gov (United States)

    Orio, Laura; Llopis, Noemi; Torres, Elisa; Izco, Maria; O'Shea, Esther; Colado, M Isabel

    2010-08-01

    3,4-Methylenedioxymethamphetamine (MDMA, 'ecstasy') is a selective 5-HT neurotoxin in rat brain which has been shown to produce acute neuroinflammation characterized by activation of microglia and release of interleukin-1beta (IL-1beta). We aimed to determine whether or not minocycline, a semi-synthetic tetracycline antibiotic capable of inhibiting microglial activation, could prevent the inflammatory response and reduce the toxicity induced by MDMA. Adult male Dark Agouti rats were given minocycline twice a day for 2 days (45 mg/kg on the first day and 90 mg/kg on the second day; 12-h apart, i.p.). MDMA (12.5 mg/kg; i.p.) was given after the third minocycline injection and animals were killed either 1 h later for the determination of NFkappaB binding activity, 3 h later for the determination of IL-1beta, 24 h later for the determination of microglial activation or 7 days later for the determination of [(3)H]-paroxetine binding as a measure of 5-HT neurotoxicity. MDMA increased NFkappaB activation, IL-1beta release and microglial activation both in the frontal cortex and in the hypothalamus and 7 days later produced a reduction in the density of 5-HT uptake sites in both these brain areas. Minocycline prevented the MDMA-induced increase in NFkappaB activation, IL-1beta release and microglial activation in the frontal cortex and prevented the 5-HT neurotoxicity 7 days later. However, in the hypothalamus, in spite of preventing MDMA-induced microglial activation, minocycline failed to prevent MDMA-induced NFkappaB activation, IL-1beta release and neurotoxicity. This suggests that the protective mechanism of minocycline against MDMA-induced neurotoxicity in frontal cortex involves inhibition of MDMA-induced NFkappaB activation possibly through a reduction in IL-1beta signalling.

  4. Inhibition of caspases and intracellular free Ca2+ concentrations are involved in resveratrol protection against apoptosis in rat primary neuron cultures

    Institute of Scientific and Technical Information of China (English)

    Qi-hai GONG; Qian WANG; Jing-shan SHI; Xie-nan HUANG; Qiong LIU; Hu MA

    2007-01-01

    Aim:To investigate the influence of resveratrol (Res),a nutritional antioxidant,on the inhibition of apoptosis in rat primary neuron cultures. Methods:The cultured cortical neurons of neonatal Sprague-Dawley rats were pretreated with Res (0. 1,1.0,and 10.0μmol/L) and oxygen-glucose deprivation/reperfusion (OGD/RP) with oxygen and glucose were initiated at d 10 in vitro. Neuronal apoptosis was determined by flow cytometry,and morphological changes of neurons were observed by an electron microscope. For the mechanism studies,the intracellular free calcium concentration ([Ca2+]i) and the transcription of caspases-3 and -12 in neurons were detected by Fura 2/AM loading and real-time RT-PCR,respectively.Results:OGD/RP insult could induce an increase in the apoptotic rate of neurons (from 11.1% to 49.0%),and elicit an obvious morphological change in neurons;pretreatments with Res (0.1,1.0,and 10.0 μmol/L,respectively) significantly reduced the elevated rate of apoptosis to 41.7%,40.8%,and 37.4%,respectively,and ameliorated the neuronal morphological injury. Similarly,the OGD/RP insult obviously elicited the elevated levels of the [Ca2+]i and the expressions of caspases-3 and-12 mRNA in neurons. Res pretreatments markedly depressed the neuronal abnormal elevation of [Ca2+]i and the overexpression of caspases-3 and -12 mRNA in a concentration-dependent manner. Conclusion:Res can attenuate the rat cortical neuronal apoptosis induced by OGD/RP. The mechanisms are,at least partly,due to the inhibition of the calcium overload and the overexpression of caspases-3 and - 12 mRNA.

  5. Partial Abstracts of East China Symposium of Biochemistry & Molecular Biology-2003 (Part Ⅱ)——Signal Transduction Pathway of the Protective Effects of Ginkgolides on Chemical Hypoxia Injury to CorticalNeurons

    Institute of Scientific and Technical Information of China (English)

    LiZHU; YeZHANG; Hong-ShanCHEN; Shu-YiJIN

    2004-01-01

    Ginkgolides (Gin), mainly including A, B, C, J, M and belonging to terpene lactone are one of the main active constituents in the extractof leaves of Ginkgo biloba L. Gin B is a specific and potent antagonist of platelet-activating factor (PAF). Some animal and clinical data showthe potential anti-ischemic/hypoxic effects and obvious protective effects of Gin on neurons, however the mechanisms of which and specially

  6. Innate immunity and protective neuroinflammation: new emphasis on the role of neuroimmune regulatory proteins.

    Science.gov (United States)

    Griffiths, M; Neal, J W; Gasque, P

    2007-01-01

    Brain inflammation due to infection, hemorrhage, and aging is associated with activation of the local innate immune system as expressed by infiltrating cells, resident glial cells, and neurons. The innate immune response relies on the detection of "nonself" and "danger-self" ligands behaving as "eat me signals" by a plethora of pattern recognition receptors (PRRs) expressed by professional and amateur phagocytes to promote the clearance of pathogens, toxic cell debris (amyloid fibrils, aggregated synucleins, prions), and apoptotic cells accumulating within the brain parenchyma and the cerebrospinal fluid (CSF). These PRRs (e.g., complement, TLR, CD14, scavenger receptors) are highly conserved between vertebrates and invertebrates and may represent the most ancestral innate scavenging system involved in tissue homeostasis. However, in some diseases, these protective mechanisms lead to neurodegeneration on the ground that several innate immune molecules have neurocytotoxic activities. The response is a "double-edged sword" representing a fine balance between protective and detrimental effects. Several key regulatory mechanisms have now been evidenced in the control of CNS innate immunity, and these could be harnessed to explore novel therapeutic avenues. We will herein provide new emphasis on the role of neuroimmune regulatory proteins (NIRegs), such as CD95L, TNF, CD200, CD47, sialic acids, CD55, CD46, fH, C3a, HMGB1, which are involved in silencing innate immunity at the cellular and molecular levels and suppression of inflammation. For instance, NIRegs may play an important role in controlling lymphocyte/macrophage/microglia hyperinflammatory responses, while sparing host defense and repair mechanisms. Moreover, NIRegs have direct beneficial effects on neurogenesis and contributing to brain tissue remodeling.

  7. 五味子酮保护大鼠皮层神经元对抗氯胺酮损伤的实验研究%Protective effect of schisandrone on ketamine-induced damage in cultured rat cortical neurons

    Institute of Scientific and Technical Information of China (English)

    张明; 蔡志平; 赵志英

    2012-01-01

    目的 研究五味子酮是否具有保护神经元免受氯胺酮损伤的作用.方法 原代培养的神经元分别加入不同浓度的氯胺酮、五味子酮后培养24 h,观察神经元形态特征和检测神经元存活率.结果 神经元经不同浓度氯胺酮处理后胞体立体感消失,颜色变暗,细胞轮廓不清,较高浓度氯胺酮组神经元轴突断裂,部分死亡.与对照组比较随着氯胺酮剂量的增加神经元存活率逐渐下降(P<0.05).20 μmol/L氯胺酮分别加入30、50、70 μmol/L五味子酮处理组神经元存活率明显高于20 μmol/L氯胺酮组(P<0.05),且70 μmol/L五味子酮组神经元存活率高于其他两组(P<0.05).结论 氯胺酮具有损伤体外培养神经元的作用且成剂量依赖性,五味子酮具有保护神经元免受氯胺酮损伤的作用.%Objective To investigate the protective effect of schisandrone on ketamine-induced damage in cultured rat cortical neurons. Methods Primary cultured neurons were treated respectively by ketamine and schisandrone with different concentration for 24 hours. Neuron morphology was observed and neuron vitality was measured by MTT assay. Results Lack of three-dimensional sense,faded color,uncleared outline were observed in neurons treated by ketamine with different concentrations. Fractured neuron axons or neurons death were observed in neurons treated by high dosage of ketamine. The neuron surviving rate was decreased with the increase of ketamine dosage compared with the figures in the control group ( P <0. 05 ). The surviving rate of neurons treated by 20 μmol/L ketamine combined with 30,50,70 μmol/L schisandrone was higher than those treated by 20 μmol/L ketamine. The surviving rate of neurons treated by 70 μmol/L schisandrone was higher than that of the other two groups ( P <0. 05 ). Conclusion Ketamine can induce injury in cultured neurons in a dosage-dependent way and schisandrone has protective effect on ketamin induced neuron damage.

  8. P2X7 receptor antagonists protect against N-methyl-D-aspartic acid-induced neuronal injury in the rat retina.

    Science.gov (United States)

    Sakamoto, Kenji; Endo, Kanako; Suzuki, Taishi; Fujimura, Kyosuke; Kurauchi, Yuki; Mori, Asami; Nakahara, Tsutomu; Ishii, Kunio

    2015-06-05

    Activation of N-methyl-d-aspartic acid (NMDA) receptors followed by a large Ca(2+) influx is thought to be a mechanism of glaucoma-induced neuronal cell death. It is possible that damage-associated molecular patterns leak from injured cells, such as adenosine triphosphate, causing retinal ganglion cell death in glaucoma. In the present study, we histologically investigated whether antagonists of the P2X7 receptor protected against NMDA-induced retinal injury in the rat in vivo. Under ketamine/xylazine anesthesia, male Sprague-Dawley rats were subjected to intravitreal injection of NMDA. We used A438079 (3-(5-(2,3-dichlorophenyl)-1H-tetrazol-1-yl)methyl pyridine) and brilliant blue G as P2X7 receptor antagonists. Upon morphometric evaluation 7 days after an intravitreal injection (200 nmol/eye), NMDA-induced cell loss was apparent in the ganglion cell layer. Intravitreal A438079 (50 pmol/eye) simultaneously injected with NMDA and intraperitoneal brilliant blue G (50 mg/kg) administered just before the NMDA injection as well as 24 and 48h after significantly reduced cell loss. In addition, A438079 decreased the number of terminal deoxynucleotidyl transferase dUTP nick end labeling-positive cells 12h after NMDA injection. P2X7 receptors were immunolocalized in the ganglion cell layer and the inner and outer plexiform layers, whereas the immunopositive P2X7 receptor signal was not detected on the Iba1-positive microglial cells that infiltrated the retina 12h after NMDA injection. The present study shows that stimulation of the P2X7 receptor is involved in NMDA-induced histological damage in the rat retina in vivo. P2X7 receptor antagonists may be effective in preventing retinal diseases caused by glutamate excitotoxicity, such as glaucoma and retinal artery occlusion.

  9. Protection of dopaminergic neurons in a mouse model of Parkinson's disease by a physically-modified saline containing charge-stabilized nanobubbles.

    Science.gov (United States)

    Khasnavis, Saurabh; Roy, Avik; Ghosh, Supurna; Watson, Richard; Pahan, Kalipada

    2014-03-01

    Neuroinflammation underlies the pathogenesis of various neurodegenerative disorders including Parkinson's disease (PD). Despite intense investigations, no effective therapy is available to stop its onset or halt its progression. RNS60 is a novel therapeutic containing charge-stabilized nanobubbles in saline, generated by subjecting normal saline to Taylor-Couette-Poiseuille flow under elevated oxygen pressure. Recently, we have delineated that RNS60 inhibits the expression of proinflammatory molecules in glial cells via type 1A phosphatidylinositol-3 kinase (PI3K)-mediated upregulation of IκBα. In this study, we demonstrate that RNS60 inhibited the expression of proinflammatory molecules in cultured microglial cells stimulated by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridium ion (MPP(+)) and in vivo in the nigra of MPTP-intoxicated mice. While investigating the underlying mechanisms, we found that MPTP intoxication rapidly stimulated the activation of type IB PI3K p110γ in the nigra, while suppressing the activation of type IA PI3K p110α/β. Interestingly, RNS60 treatment suppressed the activation of p110γ PI3K, while inducing the activation of p110α/β PI3K in the nigra of MPTP-intoxicated mice. Accordingly, RNS60 treatment increased the level of IκBα and inhibited the activation of NF-κB in the SNpc of MPTP-intoxicated mice. These findings paralleled dopaminergic neuronal protection, normalized striatal neurotransmitters, and improved motor functions in MPTP-intoxicated mice. These results strongly suggest a promising therapeutic role of this simple modified saline in PD and other neuroinflammatory disorders.

  10. 17β雌二醇对氯胺酮诱导皮层神经元凋亡的影响%17β-estradiol protects cortical neurons from ketamine-induced apoptosis

    Institute of Scientific and Technical Information of China (English)

    李建立; 高冬艳; 杜彦茹; 侯艳宁

    2014-01-01

    Aim To investigate the effects of 17β-es-tradiol on the apoptosis induced by ketamine in primary cultured cortical neurons. Methods Primary cultured cortical neurons were treated with different concentra-tions of ketamine or 17β-estradiol respectively. 24 hours after various treatments, neuron viability was measured by MTT assay. The structure of neurons was analyzed using microscope. Apoptotic neurons were de-termined by the TUNEL assay. The level of pAkt ex-pression was analyzed by Western blot. ResultsCompared with the control group, ketamine decreased neuron viability in a dose-dependent manner. Com-pared with ketamine group, 17β-estradiol increased neuron viability in a dose-dependent manner. Lack of three-dimensional sense,faded color,uncleared outline were observed, and fractured neuron axons or neurons death were also observed in neurons treated by 100μmol · L-1 ketamine. 100 μmol · L-1 ketamine in-creased the number of apoptotic neurons and decreased the expression of pAkt. 0.1 μmol · L-1 17β-estradiol decreased the number of apoptotic neurons and in-creased the expression of pAkt. LY294002 inhibited the protective effects of 17β-estradiol, the number of apoptotic neurons increased, and the level of pAkt de-creased significantly. Conclusion 17β-estradiol ex-erts the neuroprotective effects against ketamine-in-duced neuroapoptosis by activating the PI3 K/Akt sig-naling pathway.%目的:研究17β雌二醇对氯胺酮诱导的原代培养皮层神经元凋亡的影响。方法原代培养大鼠皮层神经元,分别给予不同浓度的氯胺酮及17β雌二醇培养24 h,MTT法检测神经元的存活率,显微镜下观察神经元的形态变化, TUNEL法检测神经元调亡,Western blot法测定pAkt蛋白的表达。结果与对照组比较,氯胺酮能剂量依赖性降低神经元存活率。与氯胺酮组比较,17β雌二醇能剂量依赖性提高神经元的存活率。100μmol·L-1氯胺酮组显微镜下神经元数量减少,胞体

  11. Activated microglia induce bone marrow mesenchymal stem cells to produce glial cell-derived neurotrophic factor and protect neurons against oxygen-glucose deprivation injury

    Directory of Open Access Journals (Sweden)

    Bingke Lv

    2016-12-01

    Full Text Available In this study, we investigated interactions among microglia (MG, bone marrow mesenchymal stem cells (BMSCs and neurons in cerebral ischemia and the potential mechanisms using an in vitro oxygen-glucose deprivation (OGD model. Rat BMSCs were incubated with conditioned medium (CM from in vitro cultures of OGD-activated rat MG and murine BV2 MG cells. Effects of glial cell-derived neurotrophic factor (GDNF on rat neuron viability, apoptosis, lactate dehydrogenase (LDH leakage and mitochondrial membrane potential (MMP were analyzed in this model. OGD-activated MG promoted GDNF production by BMSCs (P < 0.01. TNFα, but not IL6 or IL1β, promoted GDNF production by BMSCs (P < 0.001. GDNF or CM pre-treated BMSCs elevated neuronal viability and suppressed apoptosis (P < 0.05 or P < 0.01; these effects were inhibited by the RET antibody. GDNF activated MEK/ERK and PI3K/AKT signaling but not JNK/c-JUN. Furthermore, GDNF upregulated B cell lymphoma 2 (BCL2 and heat shock 60 kDa protein 1 (HSP60 levels, suppressed LDH leakage, and promoted MMP. Thus, activated MG produce TNFα to stimulate GDNF production by BMSCs, which prevents and repairs OGD-induced neuronal injury, possibly via regulating MEK/ERK and PI3K/AKT signaling. These findings will facilitate the prevention and treatment of neuronal injury by cerebral ischemia.

  12. Isoflurane post-conditioning protects primary cultures of cortical neurons against oxygen and glucose deprivation injury via upregulation of Slit2/Robo1.

    Science.gov (United States)

    Zhao, Xiao-Chun; Zhang, Li-Min; Li, Qiang; Tong, Dong-Yi; Fan, Long-Chang; An, Ping; Wu, Xiu-Ying; Chen, Wei-Min; Zhao, Ping; Wang, Jian

    2013-11-01

    Different mechanisms have been suggested to contribute to isoflurane-mediated neuroprotection. Previous studies have suggested that the protein Slit can abrogate neuronal death in mixed neuronal-glial cultures exposed to oxygen-glucose deprivation (OGD) and reperfusion (OGD/R). We hypothesized that isoflurane increases the expression of Slit and its receptor Robo when cortical neurons are exposed to OGD/R. To test this hypothesis, we exposed primary cortical neurons to OGD for 90 min and reperfusion for 24h and investigated how isoflurane post-conditioning affected cell survival and expression of Slit2 and receptors Robo1 and Robo4. Cell survival increased after administration of isoflurane, as assessed by the lactate dehydrogenase assay, trypan blue analysis, and propidium iodide staining. Western blot analysis showed that cleaved caspase-3 was increased after OGD/R(PSlit2 and Robo1, but not Robo4, were increased after OGD/R (PSlit2 and Robo1 expression. These findings provide a novel explanation for the pleiotropic effects of isoflurane that could benefit the central nervous system.

  13. Inhibition on the S-nitrosylation of MKK4 can protect hippocampal CA1 neurons in rat cerebral ischemia/reperfusion.

    Science.gov (United States)

    Wei, Xue Wen; Hao, Ling Yun; Qi, Su Hua

    2016-06-01

    S-nitrosylation, the nitric oxide-derived post-translational modification of proteins, plays critical roles in various physiological and pathological functions. In this present study, a rat model of cerebral ischemia and reperfusion by four-vessel occlusion was generated to assess MKK4 S-nitrosylation. Immunoprecipitation and immunoblotting were performed to evaluate MKK4 S-nitrosylation and phosphorylation. Neuronal loss was observed using histological detection. These results indicated that endogenous NO promoted the S-nitrosylation of MKK4. However, application of the exogenous NO donor S-nitrosoglutathione (GNSO), an inhibitor of the neuronal nitric oxide synthase 7-nitroindazole (7-NI), and the N-methyl-d-aspartate receptor (NMDAR) antagonist MK801 diminished I/R-induced S-nitrosylation and phosphorylation. These compounds also markedly decreased cerebral I/R-induced degeneration and death of neurons in hippocampal CA1 region in rats. Taken together, we demonstrated for the first time, that cerebral ischemia/reperfusion can induce S-nitrosylation of MKK4. We also found that inhibiting S-nitrosylation and activation of MKK4 resulted in marked decreases in neuronal degeneration and apoptosis, potentially via NMDAR-mediated mechanisms. These findings may lead to a new field of inquiry to investigate the underlying pathogenesis of stoke and the development of novel treatment strategies.

  14. Quercetin and sesamin protect dopaminergic cells from MPP+-induced neuroinflammation in a microglial (N9)-neuronal (PC12) coculture system.

    Science.gov (United States)

    Bournival, Julie; Plouffe, Marilyn; Renaud, Justine; Provencher, Cindy; Martinoli, Maria-Grazia

    2012-01-01

    A growing body of evidence indicates that the majority of Parkinson's disease (PD) cases are associated with microglia activation with resultant elevation of various inflammatory mediators and neuroinflammation. In this study, we investigated the effects of 2 natural molecules, quercetin and sesamin, on neuroinflammation induced by the Parkinsonian toxin 1-methyl-4-phenylpyridinium (MPP(+)) in a glial-neuronal system. We first established that quercetin and sesamin defend microglial cells against MPP(+)-induced increases in the mRNA or protein levels of 3 pro-inflammatory cytokines (interleukin-6, IL-1β and tumor necrosis factor-alpha), as revealed by real time-quantitative polymerase chain reaction and enzyme-linked immunoabsorbent assay, respectively. Quercetin and sesamin also decrease MPP(+)-induced oxidative stress in microglial cells by reducing inducible nitric oxide synthase protein expression as well as mitochondrial superoxide radicals. We then measured neuronal cell death and apoptosis after MPP(+) activation of microglia, in a microglial (N9)-neuronal (PC12) coculture system. Our results revealed that quercetin and sesamin rescued neuronal PC12 cells from apoptotic death induced by MPP(+) activation of microglial cells. Altogether, our data demonstrate that the phytoestrogen quercetin and the lignan sesamin diminish MPP(+)-evoked microglial activation and suggest that both these molecules may be regarded as potent, natural, anti-inflammatory compounds.

  15. Quercetin and Sesamin Protect Dopaminergic Cells from MPP+-Induced Neuroinflammation in a Microglial (N9-Neuronal (PC12 Coculture System

    Directory of Open Access Journals (Sweden)

    Julie Bournival

    2012-01-01

    Full Text Available A growing body of evidence indicates that the majority of Parkinson’s disease (PD cases are associated with microglia activation with resultant elevation of various inflammatory mediators and neuroinflammation. In this study, we investigated the effects of 2 natural molecules, quercetin and sesamin, on neuroinflammation induced by the Parkinsonian toxin 1-methyl-4-phenylpyridinium (MPP+ in a glial-neuronal system. We first established that quercetin and sesamin defend microglial cells against MPP+-induced increases in the mRNA or protein levels of 3 pro-inflammatory cytokines (interleukin-6, IL-1β and tumor necrosis factor-alpha, as revealed by real time-quantitative polymerase chain reaction and enzyme-linked immunoabsorbent assay, respectively. Quercetin and sesamin also decrease MPP+-induced oxidative stress in microglial cells by reducing inducible nitric oxide synthase protein expression as well as mitochondrial superoxide radicals. We then measured neuronal cell death and apoptosis after MPP+ activation of microglia, in a microglial (N9-neuronal (PC12 coculture system. Our results revealed that quercetin and sesamin rescued neuronal PC12 cells from apoptotic death induced by MPP+ activation of microglial cells. Altogether, our data demonstrate that the phytoestrogen quercetin and the lignan sesamin diminish MPP+-evoked microglial activation and suggest that both these molecules may be regarded as potent, natural, anti-inflammatory compounds.

  16. Geniposide, the component of the Chinese herbal formula Tongluojiunao, protects amyloid-βpeptide (1-42)-mediated death of hippocampal neurons via the non-classical estrogen signaling pathway

    Institute of Scientific and Technical Information of China (English)

    Jiao Li; Yan Tan; Qi Zhang; Xu Wang; Angran Fan; Qian Hua; Feng Wang; Haimin Ding; Chunyan Jin; Jinyan Chen; Yanan Zhao; Xiaojing Li; Wenju Chen; Ping Sun

    2014-01-01

    Tongluojiunao (TLJN) is an herbal medicine consisting of two main components, geniposide and ginsenoside Rg1. TLJN has been shown to protect primary cultured hippocampal neurons. How-ever, its mechanism of action remains unclear. In the present study, primary cultured hippocampal neurons treated with Aβ1-42 (10 µmol/L) signiifcantly increased the release of lactate dehydroge-nase, which was markedly reduced by TLJN (2 µL/mL), speciifcally by the component geniposide (26 µmol/L), but not ginsenoside Rg1 (2.5 µmol/L). hTe estrogen receptor inhibitor, ICI182780 (1 µmol/L), did not block TLJN-or geniposide-mediated decrease of lactate dehydrogenase under Aβ1-42-exposed conditions. However, the phosphatidyl inositol 3-kinase or mitogen-activated protein kinase pathway inhibitor, LY294002 (50 µmol/L) or U0126 (10 µmol/L), respectively blo cked the decrease of lactate dehydrogenase mediated by TLJN or geniposide. hTerefore, these results suggest that the non-classical estrogen pathway (i.e., phosphatidyl inositol 3-kinase or mitogen-activated protein kinase) is involved in the neuroprotective effect of TLJN, speciifcally its component, geniposide, against Aβ1-42-mediated cell death in primary cultured hippocampal neurons.

  17. Pinocembrin protects against β-amyloid-induced toxicity in neurons through inhibiting receptor for advanced glycation end products (RAGE-independent signaling pathways and regulating mitochondrion-mediated apoptosis

    Directory of Open Access Journals (Sweden)

    Liu Rui

    2012-09-01

    Full Text Available Abstract Background It is known that amyloid-β peptide (Aβ plays a pivotal role in the pathogenesis of Alzheimer's disease (AD. Interaction between Aβ and the receptor for advanced glycation end products (RAGE has been implicated in neuronal degeneration associated with this disease. Pinocembrin, a flavonoid abundant in propolis, has been reported to possess numerous biological activities beneficial to health. Our previous studies have demonstrated that pinocembrin has neuroprotective effects on ischemic and vascular dementia in animal models. It has been approved by the State Food and Drug Administration of China for clinical use in stroke patients. Against this background, we investigated the effects of pinocembrin on cognitive function and neuronal protection against Aβ-induced toxicity and explored its potential mechanism. Methods Mice received an intracerebroventricular fusion of Aβ25-35. Pinocembrin was administrated orally at 20 mg/kg/day and 40 mg/kg/day for 8 days. Behavioral performance, cerebral cortex neuropil ultrastructure, neuronal degeneration and RAGE expression were assessed. Further, a RAGE-overexpressing cell model and an AD cell model were used for investigating the mechanisms of pinocembrin. The mechanisms underlying the efficacy of pinocembrin were conducted on target action, mitochondrial function and potential signal transduction using fluorescence-based multiparametric technologies on a high-content analysis platform. Results Our results showed that oral administration of pinocembrin improved cognitive function, preserved the ultrastructural neuropil and decreased neurodegeneration of the cerebral cortex in Aβ25-35-treated mice. Pinocembrin did not have a significant effect on inhibiting Aβ1-42 production and scavenging intracellular reactive oxygen species (ROS. However, pinocembrin significantly inhibited the upregulation of RAGE transcripts and protein expression both in vivo and in vitro, and also markedly

  18. Heat shock protein 70 protects against seizure-induced neuronal cell death in the hippocampus following experimental status epilepticus via inhibition of nuclear factor-κB activation-induced nitric oxide synthase II expression.

    Science.gov (United States)

    Chang, Chiung-Chih; Chen, Shang-Der; Lin, Tsu-Kung; Chang, Wen-Neng; Liou, Chia-Wei; Chang, Alice Y W; Chan, Samuel H H; Chuang, Yao-Chung

    2014-02-01

    Status epilepticus induces subcellular changes that may eventually lead to neuronal cell death in the hippocampus. Based on an animal model of status epilepticus, our laboratory showed previously that sustained hippocampal seizure activity activates nuclear factor-κB (NF-κB) and upregulates nitric oxide synthase (NOS) II gene expression, leading to apoptotic neuronal cell death in the hippocampus. The present study examined the potential modulatory role of heat shock protein 70 (HSP70) on NF-κB signaling in the hippocampus following experimental status epilepticus. In Sprague-Dawley rats, kainic acid (KA) was microinjected unilaterally into the hippocampal CA3 subfield to induce prolonged bilateral seizure activity. Expression of HSP70 was elevated as early as 1h after the elicitation of sustained seizure activity, followed by a progressive elevation that peaked at 24h. Pretreatment with an antisense oligonucleotide against hsp70 decreased the HSP70 expression, and significantly augmented IκB kinase (IKK) activity and phosphorylation of IκBα, alongside enhanced nuclear translocation and DNA binding activity of NF-κB in the hippocampal CA3 neurons and glial cells. These cellular events were followed by enhanced upregulation of NOS II and peroxynitrite expression 3h after sustained seizure activity that led to an increase of caspase-3 and DNA fragmentation in the hippocampal CA3 neurons 7days after experimental status epilepticus. We concluded that HSP70 protects against apoptotic cell death induced by NF-κB activation and NOS II-peroxynitrite signaling cascade in the hippocampal CA3 and glial cells following experimental status epilepticus via suppression of IKK activity and deactivation of IκBα.

  19. 梓醇对MPP+诱导的中脑多巴胺能神经元损伤的保护作用%The protective effect of catalpol against MPP+-induce stress in mesencephalic neurons

    Institute of Scientific and Technical Information of China (English)

    田媛媛; 尹忠慧; 王海军

    2013-01-01

    为探讨梓醇对多巴胺能神经元的保护作用,本研究采用梓醇预处理中脑原代细胞,再给予MPP+(10uM)诱导多巴胺能神经元损伤。通过酪氨酸羟化酶(TH)的免疫细胞化学染色、脂质过氧化产物和细胞内活性氧类物质的检测,观察了梓醇对MPP+诱导的多巴胺神经元的影响。结果显示:经梓醇预处理可以明显对多巴胺能神经元起到保护作用,并且抑制脂质过氧化产物和活性氧自由基的生成。本研究结果提示,梓醇很可能成为氧化应激导致的神经细胞损伤性疾病的代替性化学药品。%The present study was to investigate the protective effects of catalpol on dopaminergic neurons were exposured to 1-methyl-4-phenylpyridinium (MPP+10uM)after pretreated with catalpol. The effests of catalpol on MPP+-induced oxidative stress in cultured dopaminergic neurons were observed by immunocytochemical staining for tyrosine hydroxylase(TH) and measuring intracellular reactive oxygen species(ROS). The results showed that catalpol increased neurons cellular viability and markedly attenuated MPP+-induced dopaminergic neurons death and reduced the content of ROS. These findings suggest that catalpol may be a candidate chemical for the treatment of oxidative stress-induced neurodegenerative disease.

  20. Sevoflurane Post-conditioning Protects Primary Rat Cortical Neurons Against Oxygen-Glucose Deprivation/Resuscitation: Roles of Extracellular Signal-Regulated Kinase 1/2 and Bid, Bim, Puma.

    Science.gov (United States)

    Zhang, Limin; Zhao, Xiaochun; Jiang, Xiaojing

    2015-08-01

    Temporal post-conditioning to induce neuroprotection against brain ischemia-reperfusion injury insult is considered to be an effective intervention, but the exact mechanisms of sevoflurane post-conditioning are poorly understood. Extracellular signal-related kinases 1/2 (Erk1/2) play a pivotal role in the cell growth and proliferation. The essential axis of activator Bid, Bim, Puma (BH3s) and BAX, BAK in activating the mitochondrial death program might offer common ground for cell death signal. We hypothesized that, sevoflurane post-conditioning might inhibit the expression of Bid, Bim and Puma and is activated by phosphor-Erk1/2 to reduce neuronal death. To test this hypothesis, we exposed primary cultured cortical neurons to oxygen-glucose deprivation for 1 h and resuscitation for 24 h (OGD/R). The assays of MTT, propidium iodide uptake, JC-1 fluorescence and western blot demonstrated that OGD/R exposure reduced cell viability, increased cell death, decreased mitochondrial membrane potential and the expressions of Bid, Bim, and Puma. Inhibition of Erk1/2 phosphorylation could partially attenuate 2 % of sevoflurane post-conditioning mediated increase in neuronal viability and mitochondrial membrane potential, and also a decrease in cell death and expression of Bid, Bim and Puma after OGD/R treatment. The results demonstrated that, the protection of sevoflurane post-conditioning markedly reducing death of cortical neurons exposed to OGD/R could be correlated with down-regulation of Bid, Bim and Puma expression mediated by phosphorylation/activation of Erk1/2.

  1. Protective effects of a polysaccharide fromSpirulina platensis on dopaminergic neurons in an MPTP-induced Parkinson’s disease model in C57BL/6J mice

    Institute of Scientific and Technical Information of China (English)

    Fang Zhang; Jian Lu; Ji-guo Zhang; Jun-xia Xie

    2015-01-01

    The present study aimed to determine whether a polysaccharide obtained fromSpirulina platensis shows protective effects on dopaminergic neurons. A Parkinson’s disease model was established through the intraperitoneal injection of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyr-idine (MPTP) in C57BL/6J mice. Prior to the MPTP injection, some mice were pretreated with intraperitoneal injections of a polysaccharide derived fromSpirulina platensis once daily for 10 days. The results showed that the immunoreactive staining and mRNA expression of the dopa-mine transporter and tyrosine hydroxylase, the rate-limiting enzyme in dopamine synthesis, in the substantia nigra, were signiifcantly increased in mice pretreated with 800 mg/kg of the poly-saccharide compared with those in MPTP-treated mice. The activities of superoxide dismutase and glutathione peroxidase in the serum and midbrain were also increased signiifcantly in mice injected with MPTP after pretreatment with the polysaccharide fromSpirulina platensis. By con-trast, the activity of monoamine oxidase B in serum and midbrain maintained unchanged. These experimental ifndings indicate that the polysaccharide obtained fromSpirulina platensis plays a protective role against the MPTP-induced loss of dopaminergic neurons in C57BL/6J mice, and that the antioxidative properties of this polysaccharide likely underlie its neuroprotective effect.

  2. Tetramethylpyrazine Analogue CXC195 Protects Against Dopaminergic Neuronal Apoptosis via Activation of PI3K/Akt/GSK3β Signaling Pathway in 6-OHDA-Induced Parkinson's Disease Mice.

    Science.gov (United States)

    Chen, Lin; Cheng, Li; Wei, Xinbing; Yuan, Zheng; Wu, Yanmei; Wang, Shuaishuai; Ren, Zhiping; Liu, Xinyong; Liu, Huiqing

    2016-12-22

    Parkinson's disease (PD) is a progressive neurodegenerative disorder and characterized by motor system disorders resulting in loss of dopaminergic (DA) neurons. CXC195, a novel tetramethylpyrazine derivative, has been shown strongest neuroprotective effects due to its anti-apoptotic activity. However, whether CXC195 protects against DA neuronal damage in PD and the mechanisms underlying its beneficial effects are unknown. The purpose of our study was to investigate the potential neuroprotective role of CXC195 and to elucidate its mechanism of action against 6-hydroxydopamine (6-OHDA)-induced mouse model of PD. CXC195 administration improved DA neurodegeneration in PD mice induced by 6-OHDA. Our further findings confirmed treatment of CXC195 at the dose of 10 mg/kg significantly inhibited the apoptosis by decreasing the level of cleaved caspase-3 and Bax, and increasing the level of Bcl-2 in 6-OHDA-lesioned mice. Meanwhile, 6-OHDA also decreased the amount of phosphorylated Akt while increased GSK-3β activity (the amount of phosphorylated GSK-3β at Ser9 was decreased) which was prevented by CXC195. Wortmannin, a specific PI3K inhibitor, dramatically abolished the changes induced by CXC195. Our study firstly demonstrated that CXC195 protected against DA neurodegeneration in 6-OHDA-induced PD model by its anti-apoptotic properties and PI3K/Akt/GSK3β signaling pathway was involved in it.

  3. Protein Kinase C-Related Kinase (PKN/PRK). Potential Key-Role for PKN1 in Protection of Hypoxic Neurons.

    Science.gov (United States)

    Thauerer, Bettina; Zur Nedden, Stephanie; Baier-Bitterlich, Gabriele

    2014-05-01

    Serine/threonine protein kinase C-related kinase (PKN/PRK) is a family of three isoenzymes (PKN1, PKN2, PKN3), which are widely distributed in eukaryotic organisms and share the same overall domain structure. The Nterminal region encompasses a conserved repeated domain, termed HR1a-c as well as a HR2/C2 domain. The serine/threonine kinase domain is found in the C-terminal region of the protein and shows high sequence homology to other members of the PKC superfamily. In neurons, PKN1 is the most abundant isoform and has been implicated in a variety of functions including cytoskeletal organization and neuronal differentiation and its deregulation may contribute to neuropathological processes such as amyotrophic lateral sclerosis and Alzheimer's disease. We have recently identified a candidate role of PKN1 in the regulation of neuroprotective processes during hypoxic stress. Our key findings were that: 1) the activity of PKN1 was significantly increased by hypoxia (1% O2) and neurotrophins (nerve growth factor and purine nucleosides); 2) Neuronal cells, deficient of PKN1 showed a decrease of cell viability and neurite formation along with a disturbance of the F-actinassociated cytoskeleton; 3) Purine nucleoside-mediated neuroprotection during hypoxia was severely hampered in PKN1 deficient neuronal cells, altogether suggesting a potentially critical role of PKN1 in neuroprotective processes. This review gives an up-to-date overview of the PKN family with a special focus on the neuroprotective role of PKN1 in hypoxia.

  4. Protein Kinase C-Related Kinase (PKN/PRK). Potential Key-Role for PKN1 in Protection of Hypoxic Neurons

    Science.gov (United States)

    Thauerer, Bettina; zur Nedden, Stephanie; Baier-Bitterlich, Gabriele

    2014-01-01

    Serine/threonine protein kinase C-related kinase (PKN/PRK) is a family of three isoenzymes (PKN1, PKN2, PKN3), which are widely distributed in eukaryotic organisms and share the same overall domain structure. The Nterminal region encompasses a conserved repeated domain, termed HR1a-c as well as a HR2/C2 domain. The serine/threonine kinase domain is found in the C-terminal region of the protein and shows high sequence homology to other members of the PKC superfamily. In neurons, PKN1 is the most abundant isoform and has been implicated in a variety of functions including cytoskeletal organization and neuronal differentiation and its deregulation may contribute to neuropathological processes such as amyotrophic lateral sclerosis and Alzheimer’s disease. We have recently identified a candidate role of PKN1 in the regulation of neuroprotective processes during hypoxic stress. Our key findings were that: 1) the activity of PKN1 was significantly increased by hypoxia (1% O2) and neurotrophins (nerve growth factor and purine nucleosides); 2) Neuronal cells, deficient of PKN1 showed a decrease of cell viability and neurite formation along with a disturbance of the F-actinassociated cytoskeleton; 3) Purine nucleoside-mediated neuroprotection during hypoxia was severely hampered in PKN1 deficient neuronal cells, altogether suggesting a potentially critical role of PKN1 in neuroprotective processes. This review gives an up-to-date overview of the PKN family with a special focus on the neuroprotective role of PKN1 in hypoxia. PMID:24851086

  5. Nesfatin-1 protects dopaminergic neurons against MPP+/MPTP-induced neurotoxicity through the C-Raf–ERK1/2-dependent anti-apoptotic pathway

    Science.gov (United States)

    Shen, Xiao-Li; Song, Ning; Du, Xi-Xun; Li, Yong; Xie, Jun-Xia; Jiang, Hong

    2017-01-01

    Several brain-gut peptides have been reported to have a close relationship with the central dopaminergic system; one such brain-gut peptide is nesfatin-1. Nesfatin-1 is a satiety peptide that is predominantly secreted by X/A-like endocrine cells in the gastric glands, where ghrelin is also secreted. We previously reported that ghrelin exerted neuroprotective effects on nigral dopaminergic neurons, which implied a role for ghrelin in Parkinson’s disease (PD). In the present study, we aim to clarify whether nesfatin-1 has similar effects on dopaminergic neurons both in vivo and in vitro. We show that nesfatin-1 attenuates the loss of nigral dopaminergic neurons in the 1-methyl-4-phenyl-1, 2,3,6-tetrahydropyridine (MPTP)-induced mouse model of PD. In addition, nesfatin-1 antagonized 1-methyl-4-phenylpyridillium ion (MPP+)-induced toxicity by restoring mitochondrial function, inhibiting cytochrome C release and preventing caspase-3 activation in MPP+-treated MES23.5 dopaminergic cells. These neuroprotective effects could be abolished by selective inhibition of C-Raf and the extracellular signal-regulated protein kinase 1/2 (ERK1/2). Our data suggest that C-Raf-ERK1/2, which is involved in an anti-apoptotic pathway, is responsible for the neuroprotective effects of nesfatin-1 in the context of MPTP-induced toxicity. These results imply that nesfatin-1 might have therapeutic potential for PD. PMID:28106099

  6. The calmodulin-dependent protein kinase II inhibitor KN-93 protects rat cerebral cortical neurons from N-methyl-D-aspartic acid-induced injury

    Institute of Scientific and Technical Information of China (English)

    Xuewen Liu; Cui Ma; Ruixian Xing; Weiwei Zhang; Buxian Tian; Xidong Li; Qiushi Li; Yanhui Zhang

    2013-01-01

    In this study, primary cultured cerebral cortical neurons of Sprague-Dawley neonatal rats were treated with 0.25, 0.5, and 1.0 μM calmodulin-dependent protein kinase II inhibitor KN-93 after 50 μM N-methyl-D-aspartic acid-induced injury. Results showed that, compared with N-methyl-Daspartic acid-induced injury neurons, the activity of cells markedly increased, apoptosis was significantly reduced, leakage of lactate dehydrogenase decreased, and intracellular Ca2+ concentrations in neurons reduced after KN-93 treatment. The expression of caspase-3, phosphorylated calmodulin-dependent protein kinase II and total calmodulin-dependent protein kinase II protein decreased after KN-93 treatment. And the effect was apparent at a dose of 1.0 μM KN-93. Experimental findings suggest that KN-93 can induce a dose-dependent neuroprotective effect, and that the underlying mechanism may be related to the down-regulation of caspase-3 and calmodulin- dependent protein kinase II expression.

  7. Orexin-A promotes Glu uptake by OX1R/PKCα/ERK1/2/GLT-1 pathway in astrocytes and protects co-cultured astrocytes and neurons against apoptosis in anoxia/hypoglycemic injury in vitro.

    Science.gov (United States)

    Shu, Qing; Zhang, Jianhuai; Ma, Wei; Lei, Youying; Zhou, Dan

    2017-01-01

    Orexin-A, which is an endogenous neuropeptide, is reported to have a protective role in ischemic stroke. High-concentration glutamic acid (Glu) induced by hypoxia injury in ischemic stroke can be inhibited by glial glutamate transporter GLT-1 which is only expressed in astroglia cells. A previous study reported that Orexin-A may regulate GLT-1 expression. However, the role of orexin-A in the regulation of GLT-1 in ischemic stroke still remains unclear. In this study, we aimed to investigate the effect and the underlying mechanism of orexin-A on Glu uptake in astrocytes in vitro and this effect on protecting the neurons from anoxia/hypoglycemic injury. The expression of GLT-1 significantly increased in the astrocytes with orexin-A treatment under anoxia/hypoglycemic conditions, promoting the uptake of Glu and inhibiting the apoptosis of co-cultured cells of astrocytes and neurons. However, these effects were significantly weakened by treatment with orexin-A receptor 1 (OX1R) antagonist. Orexin-A significantly up-regulated the expressions of PKCα and ERK1/2 under anoxia/hypoglycemic conditions in astrocytes, whereas the OX1R antagonist markedly reversed the effect. Furthermore, PKCα or ERK1/2 inhibitor significantly constrained the GLT-1 expression in astrocytes and facilitated the apoptosis of co-cultured cells, and GLT-1 overexpression could reverse those effects of PKCα or ERK1/2 inhibitor. Taken together, orexin-A promoted the GLT-1 expression via OX1R/PKCα/ERK1/2 pathway in astrocytes and protected co-cultured cells against anoxia/hypoglycemic injury.

  8. 1-[2-(4-Benzyloxyphenoxy)Ethyl]Imidazole inhibits monoamine oxidase B and protects against neuronal loss and behavioral impairment in rodent models of Parkinson's disease.

    Science.gov (United States)

    Chung, Jin Yong; Lee, Ji Won; Ryu, Choon Ho; Min, Hye Kyung; Yoon, Yeo Jin; Lim, Mi Jung; Park, Cheol Hyoung

    2015-08-01

    Monoamine oxidase B (MAO-B) is well known as a therapeutic target for Parkinson's disease (PD). MAO-B inhibitors retain antiparkinsonism abilities to improve motor function and prevent neuronal loss by decreasing dopamine metabolism and oxidative stress in the brain. From the study to find novel antiparkinsonism drugs that can inhibit MAO-B activity, neuronal loss, and behavioral deficits in the mouse model of PD, we identified that 1-[2-(4-benzyloxyphenoxy)ethyl]imidazole (BPEI) or safinamide strongly and selectively inhibited MAO-B activities in a dose-dependent manner (IC50 of BPEI and safinamide for MAO-B were 0.016 and 0.0021 µM and for MAO-A were 70.0 and 370 µM, respectively). In ex vivo studies after an administration (30 mg/kg, i.p.) of BPEI or safinamide to normal mice, the MAO-B activity in the brain was reduced by up to 90.6% or 82.4% at 1.0 hr. BPEI (20 mg/kg, i.p.) or safinamide (20 mg/kg, i.p.) significantly reversed the behavioral impairments, dopamine levels in the striatum, and neuronal loss in the substantia nigra of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-treated mice compared with the MPTP-alone-treated group. In the 6-hydroxydopamine-induced PD rat model, behavioral improvement by levodopa sparing activity was observed in the BPEI- or safinamide-treated (20 mg/kg, i.p.) rats. Moreover, BPEI revealed additional curative activities for nonmotor symptoms of PD such as pain, anxiety, epilepsy, and depression in rodent disease models. Therefore, BPEI has broad therapeutic potential for treating motor symptoms via strong and selective inhibitory effects on MAO-B, with additional benefits for comorbid symptoms in PD.

  9. Deficiency in p38β MAPK fails to inhibit cytokine production or protect neurons against inflammatory insult in in vitro and in vivo mouse models.

    Directory of Open Access Journals (Sweden)

    Bin Xing

    Full Text Available The p38 MAPK pathway plays a key role in regulating the production of proinflammatory cytokines, such as TNFα and IL-1β, in peripheral inflammatory disorders. There are four major isoforms of p38 MAPK (p38α, β, δ, γ, with p38α and p38β the targets of most p38 MAPK inhibitor drugs. Our previous studies demonstrated that the p38α MAPK isoform is an important contributor to stressor-induced proinflammatory cytokine up-regulation and neurotoxicity in the brain. However, the potential role of the p38β MAPK isoform in CNS proinflammatory cytokine overproduction and neurotoxicity is poorly understood. In the current studies, we used primary microglia from wild type (WT and p38β knockout (KO mice in co-culture with WT neurons, and measured proinflammatory cytokines and neuron death after LPS insult. We also measured neuroinflammatory responses in vivo in WT and p38β KO mice after administration of LPS by intraperitoneal or intracerebroventricular injection. WT and p38β KO microglia/neuron co-cultures showed similar levels of TNFα and IL-1β production in response to LPS treatment, and no differences in LPS-induced neurotoxicity. The in vitro results were confirmed in vivo, where levels of TNFα and IL-1β in the CNS were not significantly different between WT or p38β KO mice after LPS insult. Our results suggest that, similar to peripheral inflammation, p38α is critical but p38β MAPK is dispensable in the brain in regards to proinflammatory cytokine production and neurotoxicity induced by LPS inflammatory insult.

  10. Dimethyl Fumarate Protects Neural Stem/Progenitor Cells and Neurons from Oxidative Damage through Nrf2-ERK1/2 MAPK Pathway

    Directory of Open Access Journals (Sweden)

    Qin Wang

    2015-06-01

    Full Text Available Multiple sclerosis (MS is the most common multifocal inflammatory demyelinating disease of the central nervous system (CNS. Due to the progressive neurodegenerative nature of MS, developing treatments that exhibit direct neuroprotective effects are needed. Tecfidera™ (BG-12 is an oral formulation of the fumaric acid esters (FAE, containing the active metabolite dimethyl fumarate (DMF. Although BG-12 showed remarkable efficacy in lowering relapse rates in clinical trials, its mechanism of action in MS is not yet well understood. In this study, we reported the potential neuroprotective effects of dimethyl fumarate (DMF on mouse and rat neural stem/progenitor cells (NPCs and neurons. We found that DMF increased the frequency of the multipotent neurospheres and the survival of NPCs following oxidative stress with hydrogen peroxide (H2O2 treatment. In addition, utilizing the reactive oxygen species (ROS assay, we showed that DMF reduced ROS production induced by H2O2. DMF also decreased oxidative stress-induced apoptosis. Using motor neuron survival assay, DMF significantly promoted survival of motor neurons under oxidative stress. We further analyzed the expression of oxidative stress-induced genes in the NPC cultures and showed that DMF increased the expression of transcription factor nuclear factor-erythroid 2-related factor 2 (Nrf2 at both levels of RNA and protein. Furthermore, we demonstrated the involvement of Nrf2-ERK1/2 MAPK pathway in DMF-mediated neuroprotection. Finally, we utilized SuperArray gene screen technology to identify additional anti-oxidative stress genes (Gstp1, Sod2, Nqo1, Srxn1, Fth1. Our data suggests that analysis of anti-oxidative stress mechanisms may yield further insights into new targets for treatment of multiple sclerosis (MS.

  11. Interleukin-1 receptor associated kinases-1/4 inhibition protects against acute hypoxia/ischemia-induced neuronal injury in vivo and in vitro.

    Science.gov (United States)

    Yang, Y-F; Chen, Z; Hu, S-L; Hu, J; Li, B; Li, J-T; Wei, L-J; Qian, Z-M; Lin, J-K; Feng, H; Zhu, G

    2011-11-24

    Neuronal Toll-like receptors (TLRs)-2 and -4 have been shown to play a pivotal role in ischemic brain injury, and the interleukin-1 receptor associated kinases (IRAKs) are considered to be the key signaling molecules involved downstream of TLRs. Here, we investigated the expression levels of IRAK-1 and -4 and the effects of IRAK-1/4 inhibition on brain ischemic insult and neuronal hypoxia-induced injury. Male Sprague-Dawley (SD) rats and the rat neuroblastoma B35 cell line were used in these experiments. Permanent middle cerebral artery occlusion (MCAO) was induced by the intraluminal filament technique, and B35 cells were stimulated with the hypoxia-mimetic, cobalt chloride (CoCl(2)). Following induction of hypoxia/ischemia (H/I), B35 cells and cerebral cortical neurons expressed higher levels of IRAK-1 and -4. Furthermore, IRAK-1/4 inhibition decreased the mortality rate, functional deficits, and ischemic infarct volume by 7 days after MCAO. Similarly, IRAK-1/4 inhibition attenuated CoCl(2)-induced cytotoxicity and apoptosis in B35 cells in vitro. Our results show that IRAK-1/4 inhibition decreased the nuclear translocation of the nuclear factor-kappaB (NF-κB) p65 subunit, the levels of activated (phosphorylated) c-jun N-terminal kinase (JNK) and cleaved caspase-3, and the secretion of TNF-α and IL-6 in B35 cells at 6 h after CoCl(2) treatment. These data suggest that IRAK-1/4 inhibition plays a neuroprotective role in H/I-induced brain injury.

  12. Protein Kinase C-Related Kinase (PKN/PRK). Potential Key-Role for PKN1 in Protection of Hypoxic Neurons

    OpenAIRE

    Thauerer, Bettina; Zur Nedden, Stephanie; Baier-Bitterlich, Gabriele

    2014-01-01

    Serine/threonine protein kinase C-related kinase (PKN/PRK) is a family of three isoenzymes (PKN1, PKN2, PKN3), which are widely distributed in eukaryotic organisms and share the same overall domain structure. The Nterminal region encompasses a conserved repeated domain, termed HR1a-c as well as a HR2/C2 domain. The serine/threonine kinase domain is found in the C-terminal region of the protein and shows high sequence homology to other members of the PKC superfamily. In neurons, PKN1 is the mo...

  13. Isoquercetin protects cortical neurons from oxygen-glucose deprivation-reperfusion induced injury via suppression of TLR4-NF-кB signal pathway.

    Science.gov (United States)

    Wang, Cai-Ping; Li, Jian-Long; Zhang, Lu-Zhong; Zhang, Xiao-Chuan; Yu, Shu; Liang, Xin-Miao; Ding, Fei; Wang, Zhi-Wei

    2013-12-01

    In the present study, oxygen-glucose deprivation followed by reperfusion (OGD/R), an in vitro model of ischemia, was used to evaluate the neuroprotective effect of isoquercetin in primary culture of rat cortical neuronal cells. It was found that isoquercetin administered prior to the insult could prevent OGD/R-induced intracellular calcium concentrations ([Ca(2+)]i) increase, lactate dehydrogenase (LDH) release and cell viability decrease. For the first time, isoquercetin is described as a neuroprotective agent that potentially explains the alleviation and prevention from OGD/R-induced injury in neurons. Mechanistic studies showed that the neuroprotective effect of isoquercetin was carried out by anti-inflammatory signaling pathway of inhibiting protein expression of toll-like receptor 4 (TLR4) and nuclear factor-kappa B (NF-κB), and mRNA expression of TNF-α and IL-6, accompanied by the anti-apoptotic signaling pathway of deactivation of extracellular-regulated kinase (ERK), Jun kinase (JNK) and p38, and inhibition of activity of caspase-3. Therefore, these studies highlighted the confirmation of isoquercetin, a flavonoid compound, as an anti-inflammation and anti-apoptosis factor which might be used as a therapeutic strategy for the ischemia/reperfusion (I/R) brain injury and related diseases.

  14. 孕酮抑制Aβ诱导星形胶质细胞活化所致神经元损伤%Progesterone protects neurons against impairment induced by Aβactivated astrocytes

    Institute of Scientific and Technical Information of China (English)

    吴洁; 吴红海; 于洋; 秦亚彬; 韩晓磊; 侯艳宁

    2014-01-01

    Aim To investigate the effect of progester-one ( PROG) in protecting the neurons against impair-ment induced by the Aβ1-42 activated astrocytes, and the underlying molecular mechanism. Methods The astrocytes were divided into 5 groups: control, Aβ, and Aβplus PROG groups treated with 3 different con-centrations of progesterone for 24h. Then, Aβand pro-gesterone were removed, and neurons were co-cultured with the treated astrocytes. MTT assay was used to e-valuate the viability of cultured neurons; ELISA was used to detect the levels of IL-1βand TNF-αin culture media of astrocytes; immunofluorescence and Western blot were performed to detect the activation of NF-κB in astrocytes. Results PROG dose dependently pro-tected against Aβ1-42 activated astrocytes induced via-bility decrease in co-cultured neurons. Aβ induced release of IL-1β and TNF-α from astrocytes, and in-crease of NF-κB activity was abolished by progesterone treatment. Conclusion PROG protects the neurons through inhibiting the reactivity of astrocytes, and the underlying mechanism involves the NF-κB signal trans-duction.%目的:探究孕酮抑制Aβ诱导的星形胶质细胞活化,发挥神经元保护作用及其机制,为孕酮在阿尔采末病( Alzheimer’ s disease, AD)防治中的应用提供实验依据。方法将原代培养的星形胶质细胞随机分为对照组、Aβ组及Aβ加3个浓度孕酮组,分别处理24 h后,与神经元共培养。MTT法检测神经元的存活率;ELISA检测条件培养液中炎症因子IL-1β和TNF-α的水平;免疫荧光法和Western blot检测星形胶质细胞NF-κB的活性。结果孕酮浓度依赖地抑制Aβ诱导的星形胶质细胞活化引起的神经元存活率下降;抑制Aβ诱导的星形胶质细胞IL-1β和TNF-α释放的升高;抑制Aβ诱导星形胶质细胞NF-κB的活性增加。结论孕酮通过抑制Aβ诱导的星形胶质细胞活化,发挥神经元保护作用,其作用机制可能与NF-κB信号通路有关。

  15. The high-affinity D2/D3 agonist D512 protects PC12 cells from 6-OHDA-induced apoptotic cell death and rescues dopaminergic neurons in the MPTP mouse model of Parkinson's disease.

    Science.gov (United States)

    Shah, Mrudang; Rajagopalan, Subramanian; Xu, Liping; Voshavar, Chandrashekhar; Shurubor, Yevgeniya; Beal, Flint; Andersen, Julie K; Dutta, Aloke K

    2014-10-01

    In this study, in vitro and in vivo experiments were carried out with the high-affinity multifunctional D2/D3 agonist D-512 to explore its potential neuroprotective effects in models of Parkinson's disease and the potential mechanism(s) underlying such properties. Pre-treatment with D-512 in vitro was found to rescue rat adrenal Pheochromocytoma PC12 cells from toxicity induced by 6-hydroxydopamine administration in a dose-dependent manner. Neuroprotection was found to coincide with reductions in intracellular reactive oxygen species, lipid peroxidation, and DNA damage. In vivo, pre-treatment with 0.5 mg/kg D-512 was protective against neurodegenerative phenotypes associated with systemic administration of MPTP, including losses in striatal dopamine, reductions in numbers of DAergic neurons in the substantia nigra (SN), and locomotor dysfunction. These observations strongly suggest that the multifunctional drug D-512 may constitute a novel viable therapy for Parkinson's disease.

  16. Protective effect of bone marrow-derived mesenchymal stem cells on dopaminergic neurons against 1-methyl-4-phenylpyridinium ion-induced neurotoxicity in rat brain slices

    Institute of Scientific and Technical Information of China (English)

    Lirong Jin; Zhen Hong; Chunjiu Zhong; Yang Wang

    2009-01-01

    BACKGROUND: To date, the use of bone marrow-derived mesenchymal stem cells (MSCs) for the treatment of Parkinson's disease have solely focused on in vivo animal models. Because of the number of influencing factors, it has been difficult to determine a consistent outcome. OBJECTIVE: To establish an injury model in brain slices of substantia nigra and striatum using 1-methyl-4-phenylpytidinium ion (MPP+), and to investigate the effect of MSCs on dopaminergic neurons following MPP+ induced damage.DESIGN, TIME AND SETTING: An in vitro, randomized, controlled, animal experiment using immunohistochemistry was performed at the Laboratory of the Department of Anatomy, Fudan University between January 2004 and December 2006.MATERIALS: Primary MSC cultures were obtained from femurs and tibias of adult Sprague Dawley rats. Organotypic brain slices were isolated from substantia nigra and striatum of 1-day-old Sprague Dawley rat pups. Monoclonal antibodies for tyrosine hydroxylase (TH, 1:5 000) were from Santa Cruz (USA); goat anti-rabbit IgG antibodies labeled with FITC were from Boster Company (China).METHODS: Organotypic brain slices were cultured for 5 days in whole culture medium supplemented with 50% DMEM, 25% equine serum, and 25% Tyrode's balanced salt solution. The medium was supplemented with 5 μg/mL Ara-C, and the culture was continued for an additional 5 days. The undergrowth of brain slices was discarded at day 10. Eugonic brain slices were cultured with basal media for an additional 7 days. The brain slices were divided into three groups: control, MPP+ exposure, and co-culture. For the MPP+ group, MPP+ (30 μmol/L) was added to the media at day 17 and brain slices were cultured for 4 days, followed by control media. For the co-culture group, the MPP+ injured brain slices were placed over MSCs in the well and were further cultured for 7 days.MAIN OUTCOME MEASURES: After 28 days in culture, neurite outgrowth was examined in the brain slices under phase

  17. Anti-Inflammatory Modulation of Microglia via CD163-Targeted Glucocorticoids Protects Dopaminergic Neurons in the 6-OHDA Parkinson's Disease Model

    DEFF Research Database (Denmark)

    Tentillier, Noemie; Etzerodt, Anders; Olesen, Mads N;

    2016-01-01

    intravenous CD163-targeted liposomes with Dexa for 3 weeks exhibited better motor performance than the control groups and had minimal glucocorticoid-driven side effects. Furthermore, these animals showed better survival of dopaminergic neurons in substantia nigra and an increased number of microglia......UNLABELLED: Increasing evidence supports a decisive role for inflammation in the neurodegenerative process of Parkinson's disease (PD). The immune response in PD seems to involve, not only microglia, but also other immune cells infiltrated into the brain. Indeed, we observed here the infiltration...... for the modulation of brain neurodegeneration and specifically highlight the potential of CD163-targeted liposomes as a therapeutic tool in PD. SIGNIFICANCE STATEMENT: The immune response now evident in the progression of Parkinson's disease comprises both local microglia and other immune cells. We provide evidence...

  18. Synthetic and endogenous cannabinoids protect retinal neurons from AMPA excitotoxicity in vivo, via activation of CB1 receptors: Involvement of PI3K/Akt and MEK/ERK signaling pathways.

    Science.gov (United States)

    Kokona, Despina; Thermos, Kyriaki

    2015-07-01

    Cannabinoids have been suggested to protect retinal ganglion cells in different models of toxicity, but their effects on other retinal neurons are poorly known. We investigated the neuroprotective actions of the endocannabinoid N-arachidonoyl ethanolamine (Anandamide/AEA) and the synthetic cannabinoids R1-Methanandamide (MethAEA) and HU-210, in an in vivo retinal model of AMPA excitotoxicity, and the mechanisms involved in the neuroprotection. Sprague-Dawley rats were intravitreally injected with PBS or AMPA in the absence or presence of the cannabinoid agonists. Brain nitric oxide synthase (bNOS) and choline acetyltransferase (ChAT) immunoreactivity (IR), as well as TUNEL staining, assessed the AMPA-induced retinal amacrine cell loss and the dose-dependent neuroprotection afforded by cannabinoids. The CB1 receptor selective antagonist AM251 and the PI3K/Akt inhibitor wortmannin reversed the cannabinoid-induced neuroprotection, suggesting the involvement of CB1 receptors and the PI3K/Akt pathway in cannabinoids' actions. Experiments with the CB2 agonist JWH015 and [(3)H]CP55940 radioligand binding suggested that the CB2 receptor is not involved in the neuroprotection. AEA and HU-210 induced phosphorylation of Akt but only AEA induced phosphorylation of ERK1/2 kinases, as revealed by western blot analysis. To investigate the role of caspase-3 in the AMPA-induced cell death, the caspase-3 inhibitor Z-DEVD-FMK was co-injected with AMPA. Z-DEVD-FMK had no effect on AMPA excitotoxicity. Moreover, no difference was observed in the phosphorylation of SAPK/JNK kinases between PBS- and AMPA-treated retinas. These results suggest that endogenous and synthetic cannabinoids protect retinal amacrine neurons from AMPA excitotoxicity in vivo via a mechanism involving the CB1 receptors, and the PI3K/Akt and/or MEK/ERK1/2 signaling pathways.

  19. 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.

  20. Voltage-dependent anion channels (VDACs) promote mitophagy to protect neuron from death in an early brain injury following a subarachnoid hemorrhage in rats.

    Science.gov (United States)

    Li, Jian; Lu, Jianfei; Mi, Yongjie; Shi, Zhao; Chen, Chunhua; Riley, John; Zhou, Changman

    2014-07-21

    The term mitophagy is coined to describe the selective removal of mitochondria by autophagy but the process itself is still contentious, especially in the early period following subarachnoid hemorrhage (SAH). In the present study, we investigated the role of mitophagy following 48h after SAH injury in rats. Specifically evaluating whether mitophagy, through voltage dependant anion channels (VDACs) interacting with microtubule-associated protein 1 light chain 3, could orchestrate the induction of apoptotic and necrotic cell death in neurons, a VDAC1siRNA and an activitor Rapamycian (RAPA), were engaged. One hundred and twelve male Sprague-Dawley rats were randomly divided into 4 groups: Sham, SAH, SAH+VDAC1siRNA, and SAH+RAPA. Outcomes measured included mortality rate, brain edema, BBB disruption, and neurobehavioral testing. We also used western blotting techniques to analyze the expressions of key mitophagic/autophagic proteins and pro-apoptotic protein such as ROS, VDAC1, LC-3II and Caspase-3. Rapamycin treatment significantly improved the mortality rate, cerebral edema, and neurobehavioral deficits; apoptotic and necrotic cell death in neurons were reduced by Rapamycin following SAH injury. However, VDAC1siRNA worsened the brain injury following SAH. Immunohistochemical staining and western blot analysis demonstrated a decreased expression of VDAC1, LC3II, and an increase of ROS and Caspase-3 followed by VDAC1siRNA administration. In conclusion, mitophagy induced by VDAC1 following SAH injury may in fact play a significant role in neuroprotection, the mechanism which may be through the attenuation of the apoptosic and necrosic molecular pathways. This translates a preservation of functional integrity and an improvement in mortality.

  1. Antagomirs targeting microRNA-134 increase hippocampal pyramidal neuron spine volume in vivo and protect against pilocarpine-induced status epilepticus.

    Science.gov (United States)

    Jimenez-Mateos, Eva M; Engel, Tobias; Merino-Serrais, Paula; Fernaud-Espinosa, Isabel; Rodriguez-Alvarez, Natalia; Reynolds, James; Reschke, Cristina R; Conroy, Ronan M; McKiernan, Ross C; deFelipe, Javier; Henshall, David C

    2015-07-01

    Emerging data support roles for microRNA (miRNA) in the pathogenesis of various neurologic disorders including epilepsy. MicroRNA-134 (miR-134) is enriched in dendrites of hippocampal neurons, where it negatively regulates spine volume. Recent work identified upregulation of miR-134 in experimental and human epilepsy. Targeting miR-134 in vivo using antagomirs had potent anticonvulsant effects against kainic acid-induced seizures and was associated with a reduction in dendritic spine number. In the present study, we measured dendritic spine volume in mice injected with miR-134-targeting antagomirs and tested effects of the antagomirs on status epilepticus triggered by the cholinergic agonist pilocarpine. Morphometric analysis of over 6,400 dendritic spines in Lucifer yellow-injected CA3 pyramidal neurons revealed increased spine volume in mice given antagomirs compared to controls that received a scrambled sequence. Treatment of mice with miR-134 antagomirs did not alter performance in a behavioral test (novel object location). Status epilepticus induced by pilocarpine was associated with upregulation of miR-134 within the hippocampus of mice. Pretreatment of mice with miR-134 antagomirs reduced the proportion of animals that developed status epilepticus following pilocarpine and increased animal survival. In antagomir-treated mice that did develop status epilepticus, seizure onset was delayed and total seizure power was reduced. These studies provide in vivo evidence that miR-134 regulates spine volume in the hippocampus and validation of the seizure-suppressive effects of miR-134 antagomirs in a model with a different triggering mechanism, indicating broad conservation of anticonvulsant effects.

  2. Late treatment with choline alfoscerate (l-alpha glycerylphosphorylcholine, α-GPC) increases hippocampal neurogenesis and provides protection against seizure-induced neuronal death and cognitive impairment.

    Science.gov (United States)

    Lee, Song Hee; Choi, Bo Young; Kim, Jin Hee; Kho, A Ra; Sohn, Min; Song, Hong Ki; Choi, Hui Chul; Suh, Sang Won

    2017-01-01

    Choline alfoscerate (α-GPC) is a common choline compound and acetylcholine precursor in the brain, which has been shown to be effective in the treatment of Alzheimer's disease and dementia. α-GPC has been shown to enhance memory and cognitive function in stroke and Alzheimer's patients but currently remains untested in patients suffering from epilepsy. This study aimed to evaluate whether α-GPC treatment after seizure can ameliorate seizure-induced cognitive impairment and neuronal injury. The potential therapeutic effects of α-GPC on seizure-induced cognitive impairment were tested in an animal model of pilocarpine-induced seizure. Seizures were induced by intraperitoneal injection of pilocarpine (25mg/kg) in male rats. α-GPC (250mg/kg) was injected into the intramuscular space once daily for one or three weeks from immediately after seizure, or from 3 weeks after the seizure onset for 3 weeks. Here we found that immediate 1-week treatment of α-GPC showed no neuroprotective effects and neurogenesis. Immediate 3-week treatment of α-GPC showed neuroprotective effect but no effect on neurogenesis. To evaluate the effect of late treatment of α-GPC on cognitive impairment following seizure, rats were injected α-GPC from 3 weeks after seizure for 3 weeks and subjected to a water maze test. In the present study, we found that administration of α-GPC starting at 3 weeks after seizure improved cognitive function through reduced neuronal death and BBB disruption, and increased neurogenesis. Therefore, α-GPC injection may serve as a beneficial treatment for improvement of cognitive function in epilepsy patients.

  3. 喜树碱对炎症诱导的多巴胺能神经元损伤的保护作用%The protective effect of camptothecin on inflammation-induced dopaminergic neurons injury

    Institute of Scientific and Technical Information of China (English)

    沈荣; 李学忠; 周小平; 丁卫祥; 陈强; 沈卉君

    2011-01-01

    目的 探讨喜树碱对炎症诱导的多巴胺能神经元(DN)损伤的保护作用及其可能机制.方法 建立DN培养体系及混合培养体系,观察不同干预下DN的生存率、酪氨酸羟化酶(TH)mRNA表达及肿瘤坏死因子α(TNF-α)、一氧化氮(NO)、白细胞介素6(IL-6)、胶质源性神经生长因子(GDNF)含量的变化.结果 在DN培养体系中,喜树碱10 mg/L较对照组明显促进DN凋亡(P<0.05).在混合培养体系中,与对照组比较,不同浓度喜树碱均增加TH阳性细胞数和THmRNA的表达(P<0.05),降低NO、TNF-α及IL-6的含量(P<0.05),但只有喜树碱10 mg/L能促进DN的凋亡(P<0.05).结论 适量的喜树碱能抑制星形胶质细胞分泌炎性介质,保护神经元.%Objective To investigate the protective effect and possible mechanism of camptothecin in the lipopolysaccharide-induced dopaminergic neurons (DN) injury. Methods After establishing DN and neuron-astrocyte mixed culture systems, the survival rate of DN, expression of tyrosine hydroxylase(TH) mRNA, the levels of tumor necrosis factor-α(TNFα), nitrogen monoxidum (NO), interleukin 6 (IL-6) and glial cell line-derived neurotrophic factor(GDNF) were detected in response to different treatments. Results Camptothecin 10 mg/L significantly promoted DN apoptosis in DN culture system (P< 0. 05 ). Compared with control group, different concentrations of camptothecin increased positive cell population and mRNA expression of TH (P<0. 05), decreased the levels of NO, TNF-α and IL-6(P<0. 05), but only carnptothecin 10 mg/L enhanced DN apoptosis in neuroN-astrocyte mixed culture system (P< 0. 05 ). Conclusion Camptothecin in a proper concentration can inhibit proinflammatory factors secreted by astrocyte, which in turn protects neuron.

  4. Phytic Acid Protects against 6-Hydroxydopamine-Induced Dopaminergic Neuron Apoptosis in Normal and Iron Excess Conditions in a Cell Culture Model

    Directory of Open Access Journals (Sweden)

    Qi Xu

    2011-01-01

    Full Text Available Iron may play an important role in Parkinson's disease (PD since it can induce oxidative stress-dependent neurodegeneration. The objective of this study was to determine whether the iron chelator, phytic acid (IP6 can protect against 6-hydroxydopamine- (6-OHDA- induced apoptosis in immortalized rat mesencephalic dopaminergic cells under normal and iron-excess conditions. Caspase-3 activity was increased about 6-fold after 6-OHDA treatment (compared to control; <.001 and 30 μmol/L IP6 pretreatment decreased it by 38% (<.05. Similarly, a 63% protection (<.001 against 6-OHDA induced DNA fragmentation was observed with IP6 pretreatment. Under iron-excess condition, a 6-fold increase in caspase-3 activity (<.001 and a 42% increase in DNA fragmentation (<.05 with 6-OHDA treatment were decreased by 41% (<.01 and 27% (<.05, respectively, with 30 μmol/L IP6. Together, our data suggest that IP6 protects against 6-OHDA-induced cell apoptosis in both normal and iron-excess conditions, and IP6 may offer neuroprotection in PD.

  5. The protective effect of myo-inositol on hippocamal cell loss and structural alterations in neurons and synapses triggered by kainic acid-induced status epilepticus.

    Science.gov (United States)

    Kotaria, Nato; Kiladze, Maia; Zhvania, Mzia G; Japaridze, Nadezhda J; Bikashvili, Tamar; Solomonia, Revaz O; Bolkvadze, Tamar

    2013-07-01

    It is known that myo-inositol pretreatment attenuates the seizure severity and several biochemical changes provoked by experimentally induced status epilepticus. However, it remains unidentified whether such properties of myo-inositol influence the structure of epileptic brain. In the present light and electron microscopic research we elucidate if pretreatment with myo-inositol has positive effect on hippocampal cell loss, and cell and synapses damage provoked by kainic acid-induced status epilepticus. Adult male Wistar rats were treated with (i) saline, (ii) saline + kainic acid, (iii) myo-inositol + kainic acid. Assessment of cell loss at 2, 14, and 30 days after treatment demonstrate cytoprotective effect of myo-inositol in CA1 and CA3 areas. It was strongly expressed in pyramidal layer of CA1, radial and oriental layers of CA3 and in less degree-in other layers of both fields. Ultrastructural alterations were described in CA1, 14 days after treatment. The structure of neurons, synapses, and porosomes are well preserved in the rats pretreated with myo-inositol in comparing with rats treated with only kainic acid.

  6. Quercetin Protects against Okadaic Acid-Induced Injury via MAPK and PI3K/Akt/GSK3β Signaling Pathways in HT22 Hippocampal Neurons.

    Directory of Open Access Journals (Sweden)

    Wei Jiang

    Full Text Available Increasing evidence shows that oxidative stress and the hyperphosphorylation of tau protein play essential roles in the progression of Alzheimer's disease (AD. Quercetin is a major flavonoid that has anti-oxidant, anti-cancer and anti-inflammatory properties. We investigated the neuroprotective effects of quercetin to HT22 cells (a cell line from mouse hippocampal neurons. We found that Okadaic acid (OA induced the hyperphosphorylation of tau protein at Ser199, Ser396, Thr205, and Thr231 and produced oxidative stress to the HT22 cells. The oxidative stress suppressed the cell viability and decreased the levels of lactate dehydrogenase (LDH, superoxide dismutase (SOD, mitochondria membrane potential (MMP and Glutathione peroxidase (GSH-Px. It up-regulated malondialdehyde (MDA production and intracellular reactive oxygen species (ROS. In addition, phosphoinositide 3 kinase/protein kinase B/Glycogen synthase kinase3β (PI3K/Akt/GSK3β and mitogen activated protein kinase (MAPK were also involved in this process. We found that pre-treatment with quercetin can inhibited OA-induced the hyperphosphorylation of tau protein and oxidative stress. Moreover, pre-treatment with quercetin not only inhibited OA-induced apoptosis via the reduction of Bax, and up-regulation of cleaved caspase 3, but also via the inhibition of PI3K/Akt/GSK3β, MAPKs and activation of NF-κB p65. Our findings suggest the therapeutic potential of quercetin to treat AD.

  7. [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.

  8. Erythropoietin protects neuron against ketamine induced injuries%促红细胞生成素保护神经元免受氯胺酮所致的损伤

    Institute of Scientific and Technical Information of China (English)

    尚游; 姚尚龙; 吴艳

    2008-01-01

    目的 研究促红细胞生成素(EPO)是否可以保护神经元免受氯胺酮所致损伤.方法 原代培养神经元,分别加入不同浓度的氯胺酮、EPO后培养24 h.噻唑蓝(MTT)法检测神经元存活率,TdT介导的dUTP缺口末端标记技术(TUNEL)检测凋亡神经元,荧光法测定半胱氨酸蛋白水解酶(caspase)-3活性,蛋白质印迹法检测磷酸化蛋白激酶B(pAkt)的表达.结果 1、10、30 μmol/L氯胺酮处理组神经元的存活率分别为(91±5)%、(42±6)%和(23±7)%,明显低于对照组(P<0.05或0.01);10 μmol/L氯胺酮分别加0.3、1、3、10 U/mlEPO处理组神经元存活率分别为(73±6)%、(86±9)%、(78±8)%和(71±10)%,明显高于10 μmol/L氯胺酮组(P<0.05或0.01).10 μmol/L氯胺酮组神经元凋亡增加,caspase-3相对活性为(280±60)%,明显高于对照组[(97±15)%,P<0.01],而pAkt的表达减少.10 μmol/L氯胺酮+1 U/mlEPO组caspase-3相对活性为(130±30)%,明显低于10 μmol/L氯胺酮组,而pAkt表达增加.磷酸肌醇3激酶(PI3K)抑制剂LY294002拮抗了EPO的作用.结论 EPO可以保护神经元免受氯胺酮导致的损伤,其保护作用是通过促进pAkt表达实现的.%Objective To investigate whether erythropoietin(EPO)protects neuron against ketamine induced injuries.Methods Neurons were obtained from SD rat brain,cultured.and treated with ketamine of the concentrations of 0.1,1,10,and 30 μmol/L respectively.Neurons not treated by any agent were used as control group.Another neurons were divided into 3 groups undergoing the treatment of ketamine of the terminal concentration of 10 μmol/L,EPO+ketamine group undergoing the treatment of 10 μmol/L ketamine and EPO of the terminal concentrations of 0.3,1,3,and 10 U/ml,and ketamine+EPO+LY294002 group undergoing the treatment of 10 μmol/L ketamine, 1 U/ml EPO, and 10 μmol/L LY294002,a P13k inhibitor.Twenty-four hours after the co-inoculation the survival rates of the neurons were detected by MTT method.The apoptotic rate

  9. The alpha7 nicotinic acetylcholine receptor-selective antagonist, methyllycaconitine, partially protects against beta-amyloid1-42 toxicity in primary neuron-enriched cultures.

    Science.gov (United States)

    Martin, Shelley E; de Fiebre, Nancy Ellen C; de Fiebre, Christopher M

    2004-10-01

    Studies have suggested that the neuroprotective actions of alpha7 nicotinic agonists arise from activation of receptors and not from the extensive desensitization which rapidly follows activation. Here, we report that the alpha7-selective nicotinic antagonist, methyllycaconitine (MLA), protects against beta-amyloid-induced neurotoxicity; whereas the alpha4beta2-selective antagonist, dihydro-beta-erythroidine, does not. These findings suggest that neuroprotective actions of alpha7-acting agents arise from receptor inhibition/desensitization and that alpha7 antagonists may be useful neuroprotective agents.

  10. Cigarette smoke and nicotine protect dopaminergic neurons against the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine Parkinsonian toxin.

    Science.gov (United States)

    Parain, Karine; Hapdey, Céline; Rousselet, Estelle; Marchand, Véronique; Dumery, Bernard; Hirsch, Etienne C

    2003-09-12

    Epidemiological studies have found a negative association between cigarette smoking and Parkinson's disease (PD). In order to analyze the putative neuroprotective effect of cigarette smoke and nicotine, one of its major constituents, we examined their effects in an animal model of PD provoked by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) intoxication. Two groups of mice were chronically exposed to cigarette smoke (a low exposure subgroup and a high exposure subgroup; 5 exposures per day at 2-h intervals), two other groups received nicotine treatment (two doses tested 0.2 and 2 mg/kg, 5 injections i.p. per day at 2-h intervals) and one group placebo. On day 8 after the beginning of the treatment, 4 injections of MPTP hydrochloride (15 mg/kg, i.p., at 2-h intervals) or saline were administered to these animals. Nicotine and cotinine plasmatic concentration was quantified by the HPLC method, and degeneration of the nigrostriatal system was assessed by tyrosine hydroxylase (TH) immunohistochemistry. The loss of dopaminergic neurons induced by MPTP in the substantia nigra was significantly less severe in the chronic nicotine treatment groups (at 0.2 and 2 mg/kg) and the low exposure to cigarette smoke group than in the high exposure to cigarette smoke subgroup and the placebo treated subgroup. In contrast, no preservation of TH immunostaining of nerve terminals was observed in the striatum in any group. This suggests that nicotine and low exposure to cigarette smoke may have a neuroprotective effect on the dopaminergic nigrostriatal system by an as yet unknown mechanism.

  11. The N-methyl-D-aspartate antagonist, MK-801, fails to protect against neuronal damage caused by transient, severe forebrain ischemia in adult rats.

    Science.gov (United States)

    Buchan, A; Li, H; Pulsinelli, W A

    1991-04-01

    The neuroprotective effects of dizocilipine maleate (MK-801), a noncompetitive antagonist of the N-methyl-D-aspartate (NMDA) receptor/channel, were tested in the 4-vessel occlusion rat model of forebrain ischemia. Adult Wistar rats, treated intraperitoneally with MK-801 or saline using several different treatment paradigms were subjected to 5 (n = 208) or 15 (n = 62) min of severe, transient forebrain ischemia. In saline-treated animals, 15 min of ischemia (n = 13) produced extensive and consistent loss of pyramidal neurons in the CA1 zone of hippocampus. The degree and distribution of cell loss were not reduced by single dose preischemic administration of MK-801 at 1 (n = 7), 2.5 (n = 4), or 5 mg/kg (n = 8). In other animals subjected to 15 min of forebrain ischemia, multiple doses of MK-801 (5, 2.5, and 2.5 mg/kg) given immediately and at approximately 8 and 20 hr after cerebral reperfusion (n = 5) did not alter CA1 injury compared to saline-treated controls (n = 5). Five minutes of forebrain ischemia in saline-treated animals, (n = 82) resulted in significantly fewer (p less than 0.001) dead CA1 pyramidal cells and a greater variance compared to animals subjected to 15 min of ischemia. Power analysis of the preliminary saline-treated animals subjected to 5 min of ischemia (n = 22) indicated that 60 animals per group were necessary to detect a 15% difference between MK-801 and vehicle-treated groups. Multidose treatment with MK-801 (1 mg/kg) given 1 hr prior to 5 min of ischemia (n = 60) and again at approximately 8 and 16 hr after recirculation failed to attenuate hippocampal injury.(ABSTRACT TRUNCATED AT 250 WORDS)

  12. Select estrogens within the complex formulation of conjugated equine estrogens (Premarin® are protective against neurodegenerative insults: implications for a composition of estrogen therapy to promote neuronal function and prevent Alzheimer's disease

    Directory of Open Access Journals (Sweden)

    Brinton Roberta

    2006-03-01

    Full Text Available Abstract Background Results of the Women's Health Initiative Memory Study (WHIMS raised concerns regarding the timing and formulation of hormone interventions. Conjugated equine estrogens (CEE, used as the estrogen therapy in the WHIMS trial, is a complex formulation containing multiple estrogens, including several not secreted by human ovaries, as well as other biologically active steroids. Although the full spectrum of estrogenic components present in CEE has not yet been resolved, 10 estrogens have been identified. In the present study, we sought to determine which estrogenic components, at concentrations commensurate with their plasma levels achieved following a single oral dose of 0.625 mg CEE (the dose used in the WHIMS trial in women, are neuroprotective and whether combinations of those neuroprotective estrogens provide added benefit. Further, we sought, through computer-aided modeling analyses, to investigate the potential correlation of the molecular mechanisms that conferred estrogen neuroprotection with estrogen interactions with the estrogen receptor (ER. Results Cultured basal forebrain neurons were exposed to either β-amyloid25–35 or excitotoxic glutamate with or without pretreatment with estrogens followed by neuroprotection analyses. Three indicators of neuroprotection that rely on different aspects of neuronal damage and viability, LDH release, intracellular ATP level and MTT formazan formation, were used to assess neuroprotective efficacy. Results of these analyses indicate that the estrogens, 17α-estradiol, 17β-estradiol, equilin, 17α-dihydroequilin, equilinen, 17α-dihydroequilenin, 17β-dihydroequilenin, and Δ8,9-dehydroestrone were each significantly neuroprotective in reducing neuronal plasma membrane damage induced by glutamate excitotoxicity. Of these estrogens, 17β-estradiol and Δ8,9-dehydroestrone were effective in protecting neurons against β-amyloid25–35-induced intracellular ATP decline

  13. Protective effect of paclitaxel on injury of hippocampal neurons induced by cerebral ischemia-reperfusion%紫杉醇对脑缺血-再灌注诱导海马神经元损伤的保护作用

    Institute of Scientific and Technical Information of China (English)

    齐素华; 巩娟娟; 倪小宇

    2012-01-01

    目的 研究紫杉醇对脑缺血-再灌注(I-R)后海马神经元损伤的保护作用及分子机制.方法 SD大鼠随机分为假手术对照组(A组)、I-R对照组(B组)、1% DMSO溶剂处理组(C组)、紫杉醇8 μg/kg组(D组,缺血前30 min脑室注射),每组各10只.采用大鼠四动脉结扎全脑缺血模型,应用免疫印迹法检测紫杉醇对B细胞淋巴瘤-白血病2(Bcl-2)、半胱天冬氨酸蛋白酶3(Caspase-3)表达的影响.结果 与A组相比,B、C组Bcl-2及Caspase-3磷酸化表达增加(P<0.05),而D组Bcl-2及Caspase-3磷酸化表达较B组明显减少(P<0.05).结论 紫杉醇可能对脑I-R诱导海马神经元的损伤有保护作用;这种保护作用可能与Bcl-2、Caspase-3蛋白活性密切相关.%Objective To investigate the effect and molecular mechanism of paclitaxel on the injury of hippocampal neurons induced by cerebral ischemia-reperfusion(I-R). Methods SD rats were randomly divided into four groups of A(sham operation) ,B(I-R model) ,C(injection of 1% DMSO) and D(intraventricular injection of paclitaxel 8 μg/kg 30 min before ischemia) with 10 rats each. The cerebral ischemia model was established by four-vessel occlusion, and the expressions of B cell lymphoma/leukemia-2(Bcl-2) and cystein asparate proteinase-3(Caspase-3) were detected by Western blot Results Compared with group A, the phosphorylation of Bcl-2 and Caspase-3 was increased in groups of B and C(P<0. 05). However, the phosphorylation of Bcl-2 and Caspase-3 in group D was significantly lower than that in group B(P<0. 05). Conclusion Paclitaxel may protect I-R-induced injury of hippocampal neurons, which is probably related with the activation of Bcl-2 and Caspase-3.

  14. Protective effects of panax notoginseng saponins on cholinergic neurons in rats with Alzheimer disease%三七总皂苷对阿尔茨海默病大鼠脑胆碱能神经的保护作用

    Institute of Scientific and Technical Information of China (English)

    钟振国; 屈泽强; 王乃平; 王进声; 谢智光; 张凤芬; 张雯艳; 卢忠朋

    2006-01-01

    .④采用单因素方差分析进行计量资料间差异比较.主要观察指标:三七总皂苷对阿尔茨海默病大脑胆碱能神经元分布和胆碱乙酰基转移酶的影响.结果:老年大鼠75只和青年大鼠15只均进入结果分析.①青年对照组胆碱乙酰转移酶免疫阳性神经元最多,免疫阳性物质染色最深;三七总皂苷高剂量组免疫阳性神经元明显多于石杉碱甲组和模型组;模型组免疫阳性神经元较其他各组的神经元小,且数目明显减少,胞体的轴突及树突变短.②基底前脑胆碱乙酰转移酶免疫阳性细胞数:模型组明显少于其他各组(P<0.05),三七总皂苷低剂量组、石杉碱甲组、模型组明显少于老年对照组(P<0.05),石杉碱甲组、模型组明显少于三七总皂苷高、低剂量组(P<0.05),青年对照组明显高于其他各组(P<0.05).基底前脑胆碱乙酰转移酶免疫阳性细胞平均A值:变化与各组免疫阳性细胞数变化基本相同.基底前脑胆碱乙酰转移酶免疫阳性细胞平均截面积:三七总皂苷低剂量组和模型组明显小于青年对照组(P<0.05),其他各组间差异不明显(P>0.05).结论:三七总皂苷对老年性痴呆大鼠动物模型大脑胆碱能神经元具有较强的保护作用,通过改善和修复受损神经元而提高细胞存活的数量和质量、提高胆碱乙酰转移酶的含量和活性,从而保护和改善中枢胆碱能系统的功能,发挥抗老化、抗痴呆的作用.%BACKGROUND: There are no effective methods to cure Alzheimer disease (AD). Now, researches have shown that panax notoginseng saponins (PNS) play an important role in improving AD, but its mechanism is unclear.OBJECTIVE: To observe the protective effect of PNS characterized by removing blood stasis to stop bleeding and promoting blood circulation to relieve pain on pathological lesion of cholinergic neuron in rat with AD.DESIGN: Completely randomized grouping design and controlled study

  15. Protective effects of Chinese nourishing kidney herbs on neurons of striatal neurons in Parkinson's disease model mouse%补肾中药对帕金森病模型小鼠黑质-纹状体神经元的保护作用

    Institute of Scientific and Technical Information of China (English)

    田允; 蔡晶; 陈旭征; 林如辉; 刘志臻; 赵锦燕

    2011-01-01

    Objective To explore the protective effects of Chinese nourishing kidney herbs on neurons of striatal neurons in Parkinson's disease (PD) model mouse. Methods 40 PD model mice were randomly divided into five groups: epimedium, ligustrum lucidum,polygonatum, selegiline and model control groups. 8 normal male C57BL/6J strains of mice were selected into normal control group. The normal control and model control groups were administrated with water, the mice in epimedium group, ligustrum lucidum group, polygonatum group and selegiline group were administrated with epimedium, ligustrum lucidum, polygonatum and selegiline water decoction O. 5 ml, bid,respectively. After 4 weeks, striatal neurons were quickly separated on the ice. Flow cytometry analysis was used to detect the level of caspase-3, Fas, Fas-L and bcl-2. ELISA was used to detect the level of GDNF, NGF, BNGF and observe cell morphology on microscopy electron. Results The level of FasL in polygonatum group was significantly lower than that of model control group ( P < O. 05 ), not significantly lower than that of selegiline group and blank control group (P >0. 05 ); The level of Caspase-3 in epimedium, ligustrum lucidum and polygonatum groups was lower than that of model group ( P < O. 05 ), not significantly higher than that of blank control and the selegiline groups ( P >0. 05 ). Compared with selegiline and model groups, the level of NGF in polygonatum group had increased ( P <0. 05 ), not increased compared with the blank control group ( P > 0. 05 ). The level of BDNF were significantly higher in epimedium and polygonatum groups than that of model and blank control groups ( P < 0. 05 ), while the polygonatum group had higher level than the selegiline group ( P < 0. 05 ); The extent of apoptosis in treatment group had improved compared with model group. Conclusions The protective effects of Chinese nourishing kidney herbs on neurons of striatal neurons is possibly through decreasing

  16. Protective Effects of Hericium erinaceus Mycelium and Its Isolated Erinacine A against Ischemia-Injury-Induced Neuronal Cell Death via the Inhibition of iNOS/p38 MAPK and Nitrotyrosine

    Directory of Open Access Journals (Sweden)

    Kam-Fai Lee

    2014-08-01

    Full Text Available Hericium erinaceus, an edible mushroom, has been demonstrated to potentiate the effects of numerous biological activities. The aim of this study was to investigate whether H. erinaceus mycelium could act as an anti-inflammatory agent to bring about neuroprotection using a model of global ischemic stroke and the mechanisms involved. Rats were treated with H. erinaceus mycelium and its isolated diterpenoid derivative, erinacine A, after ischemia reperfusion brain injuries caused by the occlusion of the two common carotid arteries. The production of inflammatory cytokines in serum and the infracted volume of the brain were measured. The proteins from the stroke animal model (SAM were evaluated to determine the effect of H. erinaceus mycelium. H. erinaceus mycelium reduced the total infarcted volumes by 22% and 44% at a concentration of 50 and 300 mg/kg, respectively, compared to the SAM group. The levels of acute inflammatory cytokines, including interleukin-1β, interleukin-6 and tumor necrosis factor á, were all reduced by erinacine A. Levels of nitrotyrosine-containing proteins, phosphorylation of p38 MAPK and CCAAT enhancer-binding protein (C/EBP and homologous protein (CHOP expression were attenuated by erinacine A. Moreover, the modulation of ischemia injury factors present in the SAM model by erinacine A seemed to result in the suppression of reactive nitrogen species and the downregulation of inducible NO synthase (iNOS, p38 MAPK and CHOP. These findings confirm the nerve-growth properties of Hericium erinaceus mycelium, which include the prevention of ischemic injury to neurons; this protective effect seems to be involved in the in vivo activity of iNOS, p38 MAPK and CHOP.

  17. β-Amyloid1-42, HIV-1Ba-L (clade B infection and drugs of abuse induced degeneration in human neuronal cells and protective effects of ashwagandha (Withania somnifera and its constituent Withanolide A.

    Directory of Open Access Journals (Sweden)

    Kesava Rao Venkata Kurapati

    Full Text Available Alzheimer's disease (AD is characterized by progressive dysfunction of memory and higher cognitive functions with abnormal accumulation of extracellular amyloid plaques and intracellular neurofibrillary tangles throughout cortical and limbic brain regions. Withania somnifera (WS also known as 'ashwagandha' (ASH is used widely in Ayurvedic medicine as a nerve tonic and memory enhancer. However, there is paucity of data on potential neuroprotective effects of ASH against β-Amyloid (1-42 (Aβ induced neuropathogenesis. In the present study, we have tested the neuroprotective effects of Methanol: Chloroform (3:1 extract of ASH and its constituent Withanolide A (WA against Aβ induced toxicity, HIV-1(Ba-L (clade B infection and the effects of drugs of abuse using a human neuronal SK-N-MC cell line. Aβ when tested individually, induced cytotoxic effects in SK-N-MC cells as shown by increased trypan blue stained cells. However, when ASH was added to Aβ treated cells the toxic effects were neutralized. This observation was supported by cellular localization of Aβ, MTT formazan exocytosis, and the levels of acetylcholinesterase activity, confirming the chemopreventive or protective effects of ASH against Aβ induced toxicity. Further, the levels of MAP2 were significantly increased in cells infected with HIV-1(Ba-L (clade B as well as in cells treated with Cocaine (COC and Methamphetamine (METH compared with control cells. In ASH treated cells the MAP2 levels were significantly less compared to controls. Similar results were observed in combination experiments. Also, WA, a purified constituent of ASH, showed same pattern using MTT assay as a parameter. These results suggests that neuroprotective properties of ASH observed in the present study may provide some explanation for the ethnopharmacological uses of ASH in traditional medicine for cognitive and other HIV associated neurodegenerative disorders and further ASH could be a potential novel drug to

  18. Stem cells decreased neuronal cell death after hypoxic stress in primary fetal rat neurons in vitro.

    Science.gov (United States)

    Sakai, Tetsuro; Xu, Yan

    2012-01-01

    To explore stem cell-mediated neuronal protection through extracellular signaling pathways by transplanted stem cells, we sought to identify potential candidate molecules responsible for neuronal protection using an in vitro coculture system. Primary fetal rat hippocampal neurons underwent hypoxia (≤1% oxygen) for 96 h nad then were returned to a normoxic condition. The study group then received rat umbilical cord matrix-derived stem cells, while the control group received fresh media only. The experimental group showed decreased neuronal apoptosis compared to the control group [44.5 ± 1.6% vs. 71.0 ± 4.2% (mean ± SD, p = 0.0005) on day 5] and higher neuronal survival (4.9 ± 1.2 cells/100× field vs. 2.2 ± 0.3, p = 0.02 on day 5). Among 90 proteins evaluated using a protein array, stem cell coculture media showed increased protein secretion of TIMP-1 (5.61-fold), TIMP-2 (4.88), CNTF-Rα (3.42), activin A (2.20), fractalkine (2.04), CCR4 (2.02), and decreased secretion in MIP-2 (0.30-fold), AMPK α1 (0.43), TROY (0.48), and TIMP-3 (0.50). This study demonstrated that coculturing stem cells with primary neurons in vitro decreased neuronal cell death after hypoxia with significantly altered protein secretion. The results suggest that stem cells may offer neuronal protection through extracellular signaling.

  19. Possibility of medicine in preventing and protecting electromagnetic pulse-induced injury of hippocampal neurons%药物防护电磁脉冲所致海马神经元损伤的可能性

    Institute of Scientific and Technical Information of China (English)

    龚秀云; 胡亚涛; 李玉红; 许倩; 张迎春

    2006-01-01

    组在照后即刻的细胞凋亡率显著高于正常对照组,差异有显著性意义[(68.63±9.04)%,(20.14±4.34)%,P<0.01];MK801 20 μmol/L组比电磁脉冲照射组的细胞凋亡率有所下降(62.12±11.08)%,MK80120μmol/L+尼非地平1 μmol/L组的细胞凋亡率呈进一步下降趋势[(53.69±13.60)%,P<0.05)],但两个给药组的细胞凋亡率仍高于正常对照组(P<0.01).结论:MK801和尼非地平预处理可部分阻断电磁脉冲所致的海马神经元损伤;细胞内钙超载在电磁脉冲损伤机制中发挥重要作用.%BACKGROUND: Electromagnetic pulse (EMP) irradiation can cause the decline of learning and memory abilities of rats, and lead to the intracellular calcium overloading of hippocampal neurons in vitro, and then result in necrosis and apoptosis. Physical shield can alleviate the damage of electromagnetic irradiation on experimental animals, but studies of the medicine prevention and protection on cell models are still in lack.OBJECTIVE: To observe the possibility of medicine in preventing and protecting the EMP-induced injury of hippocampal neurons in vitro.DESIGN: A randomized controlled animal experiment.SETTING: Division of Basic Medical Sciences, Chengde Medical College.MATERIALS: The experiments were carried out in the Academy of Military Medical Sciences and Chengde Medical College from January 2004 to January 2005. Several neonatal Wistar rats were used.METHODS: The neonatal Wistar rats were killed by cutting heads to remove brain, and the hippocampal neurons were primarily cultured and identified. After pretreatment with MK801 [N-methyl-D-aspartate (NMDA)receptor antagonist] and nifedipine (L-type Ca2+ channel blocking agent),the primarily cultured hippocampal neurons were irradiated with EMP. The condition of our experiment was 6×l04 Y/m, pulse rise time was 20 ns,pulse width was 30 ms, and frequency was 2.5 pulse per minute for 2 minutes. The neurons cultured in special petri dish, which could be observed

  20. Protection of berberin on cortical neurons of rat injured by Aβ25-35%小檗碱对Aβ25-35损伤大鼠皮层神经元的保护作用

    Institute of Scientific and Technical Information of China (English)

    王静; 张艳军; 常亮堂

    2011-01-01

    Objective To observe the protective effect of berberin on the cortical neurons of rat injured by Aβ25-35 and investigate its mechamism. Methods Aβ25-35 was used to treat the cortical neurons of primary culture rat, at the final concentration of 40 μg/mL for 36 h, Alzheimer's disease (AD) model was reproduced, and then interferred with berberin together. The experiments were divided into control, model, 0.5 μmol/L berberin, and 2 μmol/L berberin groups. Hoechst33258 stain assay was used to observe the morphological change, Annexin V-FITC/PI double stain flow cytometry assay was used to examine the early neural apoptisis; Western blotting assay was used to observe the activated Caspase-3 protien expression; and RT-PCR assay was used to investigate the mRNA expression of target of Rapamycin (mTOR) related genes. Results Neural apoptosis of AD model significantly increased when treated with 40 μg/mL Aβ25-35 for 36 h compared with the control group (P<0.01). Following 2 μmol/L berberin treatment, the percentage of Aβ25-35-induced cell apoptosis significantly decreased (P<0.05) compared with the model group. Berberin (0.5 and 2 μmol/mL) inhibited Aβ25-35-induced abnormal activated Caspase-3 expression, down-regulated the expression of abnormal activated mTOR mRNA and S6kinase P70S6K mRNA (P<0.05, 0.01), and up-regulated the expression of 4E binding protein (4EBP1) mRNA of AD model (P<0.01). Conclusion Berberin exhibits the protective effects against Aβ25-35-induced toxicity in cortical neurons of primary cultured rat, which maybe relates with the inhibition of mTOR signal pathway.%目的 考察小檗碱对Aβ25-35损伤的神经元的保护作用,并初步探讨其机制.方法 40μg/mL Aβ25-35作用原代培养大鼠脑皮层神经元36 h,复制阿尔茨海默病(Alzheimer's disease,AD)细胞模型,同时加入小檗碱进行干预,实验分为对照组、模型组、0.5μmol/L小檗碱组、2μmol/L小檗碱组.通过Hoechst33258染色

  1. Role of propofol in protection of neurons against ischemia/reperfusion injury%异丙酚对缺血再灌注损伤神经细胞的保护作用

    Institute of Scientific and Technical Information of China (English)

    陈娜; 周建平; 黄安宁; 袁京; 许秀丽; 冯泽国

    2011-01-01

    Objective To study the role of propofol in protection of neurons against ischemia/reperfusion (I/R) injury. Methods Hippocampal cells of Wistar rats at the age of 12h were cultured in vitro and a hypoxia and reoxygenation model of primary hippocampal cells was established. Morphology of hippocampal cells was observed. Cell survival rate was calculated with trypan blue staining. An in vivo model of I/R injury was established. The rats were divided into middle cerebral artery occlusion(MCAO) model group, propofol treatment group, and normal control group. Longa's neurological symptoms were scored. Cerebral infarction size was measured with TTC and H&E staining. Results The survived hippocampal cells were characterized by a large number of cytodendrites with a dense neuron net in hypoxia and reoxygenation model group after propofol treatment. The cell survival rate was significantly higher in propofol(100μmol/L) treatment group than in MCAO model group(56.2 ± 3.7 vs 38.6 ± 4.3, P<0.05). The score of neurological symptoms was significantly higher in 24h MCAO model group than in propofol treatment group (0.8 ± 0.5 vs 2.3 ± 0.5, P<0.05). TTC and H&E staining indicated that the infarction size was significantly smaller in propofol treatment group than in MCAO model group (123.21 ± 11.04 vs 214.95 ± 16.79, P<0.05). H&E staining showed more normal cells in propofol treatment group than in MCAO model group. Conclusion Propofol can protect neurons against I/R injury.%目的 研究异丙酚对缺血再灌注损伤神经细胞的保护作用.方法 取12h新生Wistar大鼠海马细胞进行体外培养,建立原代海马细胞缺糖缺氧再给氧模型(oxygen glucose deprivation,OGD).观察海马细胞形态,苔盼蓝染色计算细胞存活率.建立SD大鼠脑缺血再灌注损伤模型,分为模型组、异丙酚用药组、正常对照组.观测各组动物术后神经症状评分、TTC染色测定脑梗死体积大小及HE染色.结果 海马细胞缺糖缺氧再

  2. [Neuronal network].

    Science.gov (United States)

    Langmeier, M; Maresová, D

    2005-01-01

    Function of the central nervous system is based on mutual relations among the nerve cells. Description of nerve cells and their processes, including their contacts was enabled by improvement of optical features of the microscope and by the development of impregnation techniques. It is associated with the name of Antoni van Leeuwenhoek (1632-1723), J. Ev. Purkyne (1787-1869), Camillo Golgi (1843-1926), and Ramón y Cajal (1852-1934). Principal units of the neuronal network are the synapses. The term synapse was introduced into neurophysiology by Charles Scott Sherrington (1857-1952). Majority of the interactions between nerve cells is mediated by neurotransmitters acting at the receptors of the postsynaptic membrane or at the autoreceptors of the presynaptic part of the synapse. Attachment of the vesicles to the presynaptic membrane and the release of the neurotransmitter into the synaptic cleft depend on the intracellular calcium concentration and on the presence of several proteins in the presynaptic element.

  3. Reynosin protects against neuronal toxicity in dopamine-induced SH-SY5Y cells and 6-hydroxydopamine-lesioned rats as models of Parkinson's disease: Reciprocal up-regulation of E6-AP and down-regulation of α-synuclein.

    Science.gov (United States)

    Ham, Ahrom; Kim, Dong-Woo; Kim, Kyeong Ho; Lee, Sung-Jin; Oh, Ki-Bong; Shin, Jongheon; Mar, Woongchon

    2013-08-01

    Aggregation of α-synuclein (ASYN) is considered a major determinant of neuronal loss in Parkinson's disease (PD). E6-associated protein (E6-AP), an E3 ubiquitin protein ligase, has been known to promote the degradation of α-synuclein. The aim of this study was to assess the effects of the sesquiterpene lactone reynosin on dopamine (DA)-induced neuronal toxicity and regulation of E6-associated protein and α-synuclein proteins in both in vitro and in vivo models of Parkinson's disease. Usi"ng flow cytometry and western blot analysis, we determined that reynosin significantly protected both against cell death from dopamine-induced toxicity in human neuroblastoma SH-SY5Y cells and against the loss of tyrosine hydroxylase (TH)-positive cells in 6-hydroxydopamine (6-OHDA)-lesioned rats (a rodent Parkinson's disease model system). In addition, reynosin made up-regulation of E6-associated protein expression and down-regulation of the over-expression of α-synuclein protein in both dopamine-treated SH-SY5Y cells and 6-hydroxydopamine-lesioned rats. These results suggest that the protective effect of reynosin against dopamine-induced neuronal cell death may be due to the reciprocal up-regulation of E6-associated protein and down-regulation of α-synuclein protein expression.

  4. Protective effects of H2S on dopamine neurons in rats with Parkinson's disease%硫化氢对帕金森病模型大鼠多巴胺神经元的保护作用

    Institute of Scientific and Technical Information of China (English)

    尹蔚兰; 何剑琴; 张恺芳; 欧阳新平

    2011-01-01

    目的:观察硫化氢对帕金森病(Parkinson's disease,PD)大鼠神经行为学、氧化应激以及多巴胺及其代谢产物的影响.方法:采用6-羟基多巴胺(6-OHDA)注射于脑右侧黑质造成偏侧PD模型.将模型动物随机分为模型组、硫化氢组(硫氢化钠做供体),每组10只;另分别取10只正常大鼠为正常组及假手术组(以抗坏血酸注射).观察PD大鼠经过硫化氢处理后神经行为学、脑组织丙二醛(MDA)、谷胱甘肽(GSH)、超氧化物歧化酶(SOD)含量以及多巴胺代谢产物的变化.结果:与模型组比较硫化氧组大鼠行为学明显改善(P<0.01),同时脑组织中GSH、SOD含量均升高,MDA含量降低,多巴胺及其代谢产物升高.结论:硫化氢对PD模型大鼠多巴胺神经元具有保护作用.%Objective: To observe the effects of H2S prescription on neuroethology, oxidative stress, dopamine and its metabolites in rats with Parkinson's disease (PD).Methods: Model of hemilateral PD mt was established with injection of 6-hydroxydopamine( 6-OHDA )into the right substantia nigra of midbrain.The PD model rats were randomly divided into model group, H2S group (sodium hydrosulfide, NariS, was used as H2S donor), control group and sham-operated group( injected by ascorbic acid) ,10 rats for each group.The changes of neuroethology, the contents of malondialdehyde (MDA), glutathione (GSH), superoxide dismutase (SOD), and the levels of dopamine and its metabolites were compared among groups.Results: Compared with model group, the neuroethology of rats in H2S group were significantly improved.The contents of GSH, SOD were reduced significanfiy; The contents of MDA and the levels of dopamine( DA ),HVA, dihydroxv-phenyl acetic acid (DOPAC) were elevated significantly.Conclusion: H2S can protect the dopamine neurons in rats with Parkinson's disease.

  5. Protective effect of HSV-mediated gene transfer of nerve growth factor in pyridoxine neuropathy demonstrates functional activity of trkA receptors in large sensory neurons of adult animals.

    Science.gov (United States)

    Chattopadhyay, Munmun; Goss, James; Lacomis, David; Goins, William C; Glorioso, Joseph C; Mata, Marina; Fink, David J

    2003-02-01

    The distinct distribution of trkA receptors on small neurons and trkC receptors on large neurons in the dorsal root ganglion correlates with the dependence of these two classes of neurons on nerve growth factor and neurotrophin-3, respectively, for survival during development. In adult animals, the distribution of high affinity neurotrophin (trk) is complex and overlapping; neurotrophins are not required for cell survival, but may influence cell phenotype and the response to injury. In order to test the functional activity of trkA receptors in the sensory ganglia of adult animals in vivo, we examined the ability of a nerve growth factor-expressing recombinant replication-defective herpes simplex virus-based vector to prevent the selective degeneration of large sensory fibres caused by intoxication with pyridoxine. Transduction of dorsal root ganglion neurons in vivo by subcutaneous inoculation of the nerve growth factor-expressing vector prevented the development of pyridoxine-induced neuropathy measured by electrophysiological, morphological and behavioural measures. These results demonstrate a functional activity of trkA receptors expressed on large neurons in the dorsal root ganglion in mature animals; this observation has important implications for the choice of neurotrophic factors for treatment of peripheral nerve disease.

  6. General artificial neuron

    Science.gov (United States)

    Degeratu, Vasile; Schiopu, Paul; Degeratu, Stefania

    2007-05-01

    In this paper the authors present a model of artificial neuron named the general artificial neuron. Depending on application this neuron can change self number of inputs, the type of inputs (from excitatory in inhibitory or vice versa), the synaptic weights, the threshold, the type of intensifying functions. It is achieved into optoelectronic technology. Also, into optoelectronic technology a model of general McCulloch-Pitts neuron is showed. The advantages of these neurons are very high because we have to solve different applications with the same neural network, achieved from these neurons, named general neural network.

  7. NEURON and Python

    OpenAIRE

    Michael Hines; Davison, Andrew P.; Eilif Muller

    2009-01-01

    The NEURON simulation program now allows Python to be used, alone or in combination with NEURON's traditional Hoc interpreter. Adding Python to NEURON has the immediate benefit of making available a very extensive suite of analysis tools written for engineering and science. It also catalyzes NEURON software development by offering users a modern programming tool that is recognized for its flexibility and power to create and maintain complex programs. At the same time, nothing is lost because ...

  8. Blocking GSK3β-mediated dynamin1 phosphorylation enhances BDNF-dependent TrkB endocytosis and the protective effects of BDNF in neuronal and mouse models of Alzheimer's disease.

    Science.gov (United States)

    Liu, Xiang-Hua; Geng, Zhao; Yan, Jing; Li, Ting; Chen, Qun; Zhang, Qun-Ye; Chen, Zhe-Yu

    2015-02-01

    Endocytosis of tropomyosin related kinase B (TrkB) receptors has critical roles in brain-derived neurotrophic factor (BDNF) mediated signal transduction and biological function, however the mechanism that is governing TrkB endocytosis is still not completely understood. In this study, we showed that GSK3β, a key kinase in neuronal development and survival, could regulate TrkB endocytosis through phosphorylating dynamin1 (Dyn1) but not dynamin2 (Dyn2). Moreover, we found that beta-amyloid (Aβ) oligomer exposure could impair BDNF-dependent TrkB endocytosis and Akt activation through enhancing GSK3β activity in cultured hippocampal neurons, which suggested that BDNF-induced TrkB endocytosis and the subsequent signaling were impaired in neuronal model of Alzheimer's disease (AD). Notably, we found that inhibiting GSK3β phosphorylating Dyn1 by using TAT-Dyn1SpS could rescue the impaired TrkB endocytosis and Akt activation upon BDNF stimuli under Aβ exposure. Finally, TAT-Dyn1SpS could facilitate BDNF-mediated neuronal survival and cognitive enhancement in mouse models of AD. These results clarified a role of GSK3β in BDNF-dependent TrkB endocytosis and the subsequent signaling, and provided a potential new strategy by inhibiting GSK3β-induced Dyn1 phosphorylation for AD treatment.

  9. Neurite outgrowth in human iPSC-derived neurons

    Data.gov (United States)

    U.S. Environmental Protection Agency — Data on morphology of rat and human neurons in cell culture. This dataset is associated with the following publication: Druwe, I., T. Freudenrich , K. Wallace , T....

  10. Prolonged exposure of cortical neurons to oligomeric amyloid-β impairs NMDA receptor function via NADPH oxidase-mediated ROS production: protective effect of green tea (–-epigallocatechin-3-gallate

    Directory of Open Access Journals (Sweden)

    Grace Y Sun

    2011-02-01

    Full Text Available Excessive production of Aβ (amyloid β-peptide has been shown to play an important role in the pathogenesis of AD (Alzheimer's disease. Although not yet well understood, aggregation of Aβ is known to cause toxicity to neurons. Our recent study demonstrated the ability for oligomeric Aβ to stimulate the production of ROS (reactive oxygen species in neurons through an NMDA (N-methyl-d-aspartate-dependent pathway. However, whether prolonged exposure of neurons to aggregated Aβ is associated with impairment of NMDA receptor function has not been extensively investigated. In the present study, we show that prolonged exposure of primary cortical neurons to Aβ oligomers caused mitochondrial dysfunction, an attenuation of NMDA receptor-mediated Ca2+ influx and inhibition of NMDA-induced AA (arachidonic acid release. Mitochondrial dysfunction and the decrease in NMDA receptor activity due to oligomeric Aβ are associated with an increase in ROS production. Gp91ds-tat, a specific peptide inhibitor of NADPH oxidase, and Mn(III-tetrakis(4-benzoic acid-porphyrin chloride, an ROS scavenger, effectively abrogated Aβ-induced ROS production. Furthermore, Aβ-induced mitochondrial dysfunction, impairment of NMDA Ca2+ influx and ROS production were prevented by pre-treatment of neurons with EGCG [(−-epigallocatechin-3-gallate], a major polyphenolic component of green tea. Taken together, these results support a role for NADPH oxidase-mediated ROS production in the cytotoxic effects of Aβ, and demonstrate the therapeutic potential of EGCG and other dietary polyphenols in delaying onset or retarding the progression of AD.

  11. Sevoflurane post-conditioning protects primary rat cortical neurons against oxygen-glucose deprivation/resuscitation via down-regulation in mitochondrial apoptosis axis of Bid, Bim, Puma-Bax and Bak mediated by Erk1/2.

    Science.gov (United States)

    Zhang, Li-Min; Zhao, Xiao-Chun; Sun, Wen-Bo; Li, Rui; Jiang, Xiao-Jing

    2015-10-15

    Temporal post-conditioning helps provide neuroprotection against brain injury secondary to ischemia-reperfusion and is considered an effective intervention, but the exact mechanism of sevoflurane post-conditioning is unclear. The essential axis involves activator Bid, Bim, Puma (BH3s), Bax, and Bak; activates the mitochondrial death program; and might be involved in a cell death signal. Extracellular signal-related kinases 1/2 (Erk1/2) play a pivotal role in cell growth and proliferation. We hypothesized that sevoflurane post-conditioning might inhibit Bid, Bim, Puma, Bax, and Bak expression and is activated by phosphor-Erk1/2 to decrease neuronal death. To test this hypothesis, we exposed primary cortical neuron cultures to oxygen-glucose deprivation for 1h, along with resuscitation for 24h (OGD/R). MTT assays, propidium iodide uptake (PI), JC-1 fluorescence, and Western blot indicated the following: decreased cell viability (PPuma, Bax, and Bak expression with OGD/R exposure. Inhibition of Erk1/2 phosphorylation could attenuate sevoflurane post-conditioning that mediated an increase in neuronal viability and mitochondrial membrane potential, as well as a decrease in cell death and Bid, Bim, Puma, Bax, and Bak expression after OGD/R treatment. The results demonstrated that sevoflurane post-conditioning caused a marked decrease in cortical neuronal death secondary to OGD/R exposure through the downregulation of the mitochondrial apoptosis axis involving Bid, Bim, Puma, Bax, and Bak that was mediated by the phosphorylation/activation of Erk1/2.

  12. Oxygen-glucose deprivation preconditioning protects neurons against oxygen-glucose deprivation/reperfusion induced injury via bone morphogenetic protein-7 mediated ERK, p38 and Smad signalling pathways.

    Science.gov (United States)

    Guan, Junhong; Du, Shaonan; Lv, Tao; Qu, Shengtao; Fu, Qiang; Yuan, Ye

    2016-01-01

    Bone morphogenetic protein (BMP)-7 mediated neuroprotective effect of cerebral ischemic preconditioning (IPC) has been studied in an ischemic animal model, but the underlying cellular mechanisms have not been clearly clarified. In this study, primary cortical neurons and the SH-SY5Y cell line were used to investigate the role of BMP-7 and its downstream signals in the neuroprotective effects of oxygen-glucose deprivation preconditioning (OGDPC). Immunocytochemistry was used to detect the expression of neurofilament in neurons. MTT and lactate dehydrogenase activity assays were used to measure the cytotoxicity. Western blot was used to detect the protein expression of BMP-7 and downstream signals. BMP inhibitor, mitogen-activated protein kinase inhibitors, Smad inhibitor and siRNA of Smad 1 were used to investigate the role of corresponding signalling pathways in the OGDPC. Results showed that OGDPC-induced overexpression of BMP-7 in primary cortical neurons and SH-SY5Y cells. Both of endogenous and exogenous BMP-7 could replicate the neuroprotective effects seen in OGDPC pretreatment. In addition, extracellular regulated protein kinases, p38 and Smad signalling pathway were found to be involved in the neuroprotective effects mediated by OGDPC via BMP-7. This study primarily reveals the cellular mechanisms of the neuroprotection mediated by OGDPC, and provides evidence for better understanding of this intrinsic factor against ischemia.

  13. Study of a new neuron

    CERN Document Server

    Adler, Stephen Louis; Weckel, J D

    1994-01-01

    We study a modular neuron alternative to the McCulloch-Pitts neuron that arises naturally in analog devices in which the neuron inputs are represented as coherent oscillatory wave signals. Although the modular neuron can compute XOR at the one neuron level, it is still characterized by the same Vapnik-Chervonenkis dimension as the standard neuron. We give the formulas needed for constructing networks using the new neuron and training them using back-propagation. A numerical study of the modular neuron on two data sets is presented, which demonstrates that the new neuron performs at least as well as the standard neuron.

  14. Cajal bodies in neurons.

    Science.gov (United States)

    Lafarga, Miguel; Tapia, Olga; Romero, Ana M; Berciano, Maria T

    2016-09-14

    Cajal is commonly regarded as the father of modern neuroscience in recognition of his fundamental work on the structure of the nervous system. But Cajal also made seminal contributions to the knowledge of nuclear structure in the early 1900s, including the discovery of the "accessory body" later renamed "Cajal body" (CB). This important nuclear structure has emerged as a center for the assembly of ribonucleoproteins (RNPs) required for splicing, ribosome biogenesis and telomere maintenance. The modern era of CB research started in the 1990s with the discovery of coilin, now known as a scaffold protein of CBs, and specific probes for small nuclear RNAs (snRNAs). In this review, we summarize what we have learned in the recent decades concerning CBs in post-mitotic neurons, thereby ruling out dynamic changes in CB functions during the cell cycle. We show that CBs are particularly prominent in neurons, where they frequently associate with the nucleolus. Neuronal CBs are transcription-dependent nuclear organelles. Indeed, their number dynamically accommodates to support the high neuronal demand for splicing and ribosome biogenesis required for sustaining metabolic and bioelectrical activity. Mature neurons have canonical CBs enriched in coilin, survival motor neuron protein and snRNPs. Disruption and loss of neuronal CBs associate with severe neuronal dysfunctions in several neurological disorders such as motor neuron diseases. In particular, CB depletion in motor neurons seems to reflect a perturbation of transcription and splicing in spinal muscular atrophy, the most common genetic cause of infant mortality.

  15. Radiation Protection

    Science.gov (United States)

    ... EPA United States Environmental Protection Agency Search Search Radiation Protection Share Facebook Twitter Google+ Pinterest Contact Us Radiation Protection Document Library View and download EPA radiation ...

  16. Noise and Neuronal Heterogeneity

    CERN Document Server

    Barber, Michael J

    2010-01-01

    We consider signal transaction in a simple neuronal model featuring intrinsic noise. The presence of noise limits the precision of neural responses and impacts the quality of neural signal transduction. We assess the signal transduction quality in relation to the level of noise, and show it to be maximized by a non-zero level of noise, analogous to the stochastic resonance effect. The quality enhancement occurs for a finite range of stimuli to a single neuron; we show how to construct networks of neurons that extend the range. The range increases more rapidly with network size when we make use of heterogeneous populations of neurons with a variety of thresholds, rather than homogeneous populations of neurons all with the same threshold. The limited precision of neural responses thus can have a direct effect on the optimal network structure, with diverse functional properties of the constituent neurons supporting an economical information processing strategy that reduces the metabolic costs of handling a broad...

  17. Mesmerising mirror neurons.

    Science.gov (United States)

    Heyes, Cecilia

    2010-06-01

    Mirror neurons have been hailed as the key to understanding social cognition. I argue that three currents of thought-relating to evolution, atomism and telepathy-have magnified the perceived importance of mirror neurons. When they are understood to be a product of associative learning, rather than an adaptation for social cognition, mirror neurons are no longer mesmerising, but they continue to raise important questions about both the psychology of science and the neural bases of social cognition.

  18. Pacemaking Kisspeptin Neurons

    Science.gov (United States)

    Kelly, Martin J.; Zhang, Chunguang; Qiu, Jian; Rønnekleiv, Oline K.

    2013-01-01

    Kisspeptin (Kiss1) neurons are vital for reproduction. GnRH neurons express the kisspeptin receptor, GPR 54, and kisspeptins potently stimulate the release of GnRH by depolarising and inducing sustained action potential firing in GnRH neurons. As such Kiss1 neurons may be the pre-synaptic pacemaker neurons in the hypothalamic circuitry that controls reproduction. There are at least two different populations of Kiss1 neurons: one in the rostral periventricular area (RP3V) that is stimulated by oestrogens and the other in the arcuate nucleus that is inhibited by oestrogens. How each of these Kiss1 neuronal populations participate in the regulation of the reproductive cycle is currently under intense investigation. Based on electrophysiological studies in the guinea pig and mouse, Kiss1 neurons in general are capable of generating burst firing behavior. Essentially all Kiss1 neurons, which have been studied thus far in the arcuate nucleus, express the ion channels necessary for burst firing, which include hyperpolarization-activated, cyclic nucleotide gated cation (HCN) channels and the T-type calcium (Cav3.1) channels. Under voltage clamp conditions, these channels produce distinct currents that under current clamp conditions can generate burst firing behavior. The future challenge is to identify other key channels and synaptic inputs involved in the regulation of the firing properties of Kiss1 neurons and the physiological regulation of the expression of these channels and receptors by oestrogens and other hormones. The ultimate goal is to understand how Kiss1 neurons control the different phases of GnRH neurosecretion and hence reproduction. PMID:23884368

  19. Juvenil neuronal ceroid lipofuscinosis

    DEFF Research Database (Denmark)

    Ostergaard, J R; Hertz, Jens Michael

    1998-01-01

    Neuronal ceroid-lipofuscinosis is a group of neurodegenerative diseases which are characterized by an abnormal accumulation of lipopigment in neuronal and extraneuronal cells. The diseases can be differentiated into several subgroups according to age of onset, the clinical picture, neurophysiolog...

  20. Corticospinal mirror neurons.

    Science.gov (United States)

    Kraskov, A; Philipp, R; Waldert, S; Vigneswaran, G; Quallo, M M; Lemon, R N

    2014-01-01

    Here, we report the properties of neurons with mirror-like characteristics that were identified as pyramidal tract neurons (PTNs) and recorded in the ventral premotor cortex (area F5) and primary motor cortex (M1) of three macaque monkeys. We analysed the neurons' discharge while the monkeys performed active grasp of either food or an object, and also while they observed an experimenter carrying out a similar range of grasps. A considerable proportion of tested PTNs showed clear mirror-like properties (52% F5 and 58% M1). Some PTNs exhibited 'classical' mirror neuron properties, increasing activity for both execution and observation, while others decreased their discharge during observation ('suppression mirror-neurons'). These experiments not only demonstrate the existence of PTNs as mirror neurons in M1, but also reveal some interesting differences between M1 and F5 mirror PTNs. Although observation-related changes in the discharge of PTNs must reach the spinal cord and will include some direct projections to motoneurons supplying grasping muscles, there was no EMG activity in these muscles during action observation. We suggest that the mirror neuron system is involved in the withholding of unwanted movement during action observation. Mirror neurons are differentially recruited in the behaviour that switches rapidly between making your own movements and observing those of others.

  1. Culturing rat hippocampal neurons.

    Science.gov (United States)

    Audesirk, G; Audesirk, T; Ferguson, C

    2001-01-01

    Cultured neurons are widely used to investigate the mechanisms of neurotoxicity. Embryonic rat hippocampal neurons may be grown as described under a wide variety of conditions to suit differing experimental procedures, including electrophysiology, morphological analysis of neurite development, and various biochemical and molecular analyses.

  2. NEURON and Python.

    Science.gov (United States)

    Hines, Michael L; Davison, Andrew P; Muller, Eilif

    2009-01-01

    The NEURON simulation program now allows Python to be used, alone or in combination with NEURON's traditional Hoc interpreter. Adding Python to NEURON has the immediate benefit of making available a very extensive suite of analysis tools written for engineering and science. It also catalyzes NEURON software development by offering users a modern programming tool that is recognized for its flexibility and power to create and maintain complex programs. At the same time, nothing is lost because all existing models written in Hoc, including graphical user interface tools, continue to work without change and are also available within the Python context. An example of the benefits of Python availability is the use of the xml module in implementing NEURON's Import3D and CellBuild tools to read MorphML and NeuroML model specifications.

  3. Imaging calcium in neurons.

    Science.gov (United States)

    Grienberger, Christine; Konnerth, Arthur

    2012-03-08

    Calcium ions generate versatile intracellular signals that control key functions in all types of neurons. Imaging calcium in neurons is particularly important because calcium signals exert their highly specific functions in well-defined cellular subcompartments. In this Primer, we briefly review the general mechanisms of neuronal calcium signaling. We then introduce the calcium imaging devices, including confocal and two-photon microscopy as well as miniaturized devices that are used in freely moving animals. We provide an overview of the classical chemical fluorescent calcium indicators and of the protein-based genetically encoded calcium indicators. Using application examples, we introduce new developments in the field, such as calcium imaging in awake, behaving animals and the use of calcium imaging for mapping single spine sensory inputs in cortical neurons in vivo. We conclude by providing an outlook on the prospects of calcium imaging for the analysis of neuronal signaling and plasticity in various animal models.

  4. NEURON and Python

    Directory of Open Access Journals (Sweden)

    Michael Hines

    2009-01-01

    Full Text Available The NEURON simulation program now allows Python to be used, alone or in combination with NEURON's traditional Hoc interpreter. Adding Python to NEURON has the immediate benefit of making available a very extensive suite of analysis tools written for engineering and science. It also catalyzes NEURON software development by offering users a modern programming tool that is recognized for its flexibility and power to create and maintain complex programs. At the same time, nothing is lost because all existing models written in Hoc, including GUI tools, continue to work without change and are also available within the Python context. An example of the benefits of Python availability is the use of the XML module in implementing NEURON's Import3D and CellBuild tools to read MorphML and NeuroML model specifications.

  5. 依达拉奉对海人酸诱导癫痫大鼠海马神经元损伤的保护作用%Protective effect of edaravone against neuron injury in KA-induced seizure of rats

    Institute of Scientific and Technical Information of China (English)

    魏学文; 张晓伟; 常卫东

    2011-01-01

    目的:研究依达拉奉对海人酸诱导大鼠癫痫引起神经元损伤的保护作用及其分子机制.方法:SD大鼠随机分为癫痫对照组(saline组)、癫痫组(KA组)和药物对照组(KA+ saline组)及依达拉奉组(KA+ Ed组).采用脑室注射海人酸制作大鼠癫痫模型.取海马组织应用Western-blot法检测cleaved caspase-3、FasL和Fas的表达,以免疫共沉淀法检测FasL与Fas的结合;焦油紫染色来观察海马CA1区CA3/DG区锥体细胞形态并计数成活的细胞.结果:癫痫组和药物对照组FasL的表达及其与Fas的结合以及cleaved caspase-3的表达较癫痫对照组显著增加(P<0.05),而依达拉奉组较药物对照组显著降低(P<0.05),Fas的蛋白表达各组间差异未见显著性(P>0.05);依达拉奉明显改善海人酸诱导损伤的神经细胞形态,减少CA1区CA3区神经元的缺失(P<0.05).结论:依达拉奉可以通过抑制KA诱导FasL的表达及其与Fas的结合,抑制Fas/FasL通路,进而抑制easpase-3的活化对神经细胞发挥保护作用.%OBJECTIVE To investigate the neuroprotection of edaravone against neuronal death induced by kainic acid and to elucidate the molecular mechanisms. METHODS Adult male Sprague-Daley rats weighing 200-300 g were allotted into 4 groups as follows: control group (saline) .seizure group (KA) ,drug control group (KA+ saline) ,and edaravone group (Eld + KA). Seizures were induced by intracerebroventricular injection of KA dissolved in sterile saline. Edaravone was intraperitone-ally administrated to the rats 40 min before KA injection. Subsequently a series of methods including immunoprecipitation.im-munoblotting,histologic analysis were used to analyze the interaction,expression of relevant proteins as well as the survival of the CA1/CA3 pyramidal neurons. RESULTS Neuroprotective effect of edaravone was observed on neuronal injury induced by KA to hippocampal CA1 and CA3 pyramidal neurons. Edaravone could inhibit the expression of Fas

  6. Assessment of the Protection of Dopaminergic Neurons by an α7 Nicotinic Receptor Agonist, PHA 543613 Using [18F]LBT-999 in a Parkinson’s Disease Rat Model

    Science.gov (United States)

    Sérrière, Sophie; Doméné, Aurélie; Vercouillie, Johnny; Mothes, Céline; Bodard, Sylvie; Rodrigues, Nuno; Guilloteau, Denis; Routier, Sylvain; Page, Guylène; Chalon, Sylvie

    2015-01-01

    The inverse association between nicotine intake and Parkinson’s disease (PD) is well established and suggests that this molecule could be neuroprotective through anti-inflammatory action mediated by nicotinic receptors, including the α7-subtype (α7R). The objective of this study was to evaluate the effects of an agonist of α7R, PHA 543613, on striatal dopaminergic neurodegeneration and neuroinflammation in a rat model of PD induced by 6-hydroxydopamine (6-OHDA) lesion. Adult male Wistar rats were lesioned in the right striatum and assigned to either the PHA group (n = 7) or the Sham group (n = 5). PHA 543613 hydrochloride at the concentration of 6 mg/kg (PHA group) or vehicle (Sham group) was intra-peritoneally injected 2 h before 6-OHDA lesioning and then at days 2, 4, and 6 post-lesion. Positron emission tomography (PET) imaging was performed at 7 days post-lesion using [18F]LBT-999 to quantify the striatal dopamine transporter (DAT). After PET imaging, neuroinflammation was evaluated in same animals in vitro through the measurement of the microglial activation marker 18 kDa translocator protein (TSPO) by quantitative autoradiography with [3H]PK-11195. The DAT density reflecting the integrity of dopaminergic neurons was significantly decreased while the intensity of neuroinflammation measured by TSPO density was significantly increased in the lesioned compared to intact striatum in both groups. However, these both modifications were partially reversed in the PHA group compared to Sham. In addition, a significant positive correlation between the degree of lesion and the intensity of neuroinflammation was evidenced. These findings indicate that PHA 543613 exerts neuroprotective effects on the striatal dopaminergic neurons associated with a reduction in microglial activation in this model of PD. This reinforces the hypothesis that an α7R agonist could provide beneficial effects for the treatment of PD. PMID:26389120

  7. Single neuron computation

    CERN Document Server

    McKenna, Thomas M; Zornetzer, Steven F

    1992-01-01

    This book contains twenty-two original contributions that provide a comprehensive overview of computational approaches to understanding a single neuron structure. The focus on cellular-level processes is twofold. From a computational neuroscience perspective, a thorough understanding of the information processing performed by single neurons leads to an understanding of circuit- and systems-level activity. From the standpoint of artificial neural networks (ANNs), a single real neuron is as complex an operational unit as an entire ANN, and formalizing the complex computations performed by real n

  8. Neuromorphic silicon neuron circuits

    Directory of Open Access Journals (Sweden)

    Giacomo eIndiveri

    2011-05-01

    Full Text Available Hardware implementations of spiking neurons can be extremely useful for a large variety of applications, ranging from high-speed modeling of large-scale neural systems to real-time behaving systems, to bidirectional brain-machine interfaces. The specific circuit solutions used to implement silicon neurons depend on the application requirements. In this paper we describe the most common building blocks and techniques used to implement these circuits, and present an overview of a wide range of neuromorphic silicon neurons, which implement different computational models, ranging from biophysically realistic and conductance based Hodgkin-Huxley models to bi-dimensional generalized adaptive Integrate and Fire models. We compare the different design methodologies used for each silicon neuron design described, and demonstrate their features with experimental results, measured from a wide range of fabricated VLSI chips.

  9. Acupuncture does not protect against 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced damage of dopaminergic neurons in a preclinical mouse model of Parkinson's disease.

    Science.gov (United States)

    Yang, Hui-Jun; Gao, Yu; Yun, Ji Young; Kim, Young Eun; Ehm, Gwanhee; Lee, Ji Yeon; Yoon, Min-Yung; Lee, Young-Shin; Kim, Han-Joon; Jeon, Beomseok

    2017-01-01

    Acupuncture treatment, a complementary and alternative medicine, is associated with a suggested neuroprotective effect in previous preclinical studies of Parkinson's disease (PD); however, results from human clinical trials have been mixed or unsuccessful. Recent systematic reviews of translational neuroprotective studies showed that the supposed efficacy is confounded by low methodological quality, particularly by a lack of randomization and concealed allocation. We sought to replicate previous experimental findings with a study design that mitigates the introduction of bias, including randomization, blinded outcome measures, sham acupuncture application, and allocation concealment by blinded neurotoxin administration. We performed 12 sessions of manual acupuncture at acupoint GB34 (yanglingquan) in mice that were administered the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine neurotoxin for five consecutive days. In this animal model of PD, acupuncture treatment did not attenuate tyrosine hydroxylase-immunoreactive neuronal death, depletion of striatal dopamine levels, or reduced striatal tyrosine hydroxylase expression. Our results indicate that acupuncture is not neuroprotective against nigrostriatal loss in a subacute 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine mouse model of PD.

  10. Motor neurone disease.

    Science.gov (United States)

    2016-03-23

    Essential facts Motor neurone disease describes a group of related diseases, affecting the neurones in the brain and spinal cord. Progressive, incurable and life-limiting, MND is rare, with about 1,100 people developing it each year in the UK and up to 5,000 people affected at any one time. One third of people will die within a year of diagnosis and more than half within two years. About 5% to 10% are alive at ten years.

  11. Planar multipolar cells in the cochlear nucleus project to medial olivocochlear neurons in mouse.

    Science.gov (United States)

    Darrow, Keith N; Benson, Thane E; Brown, M Christian

    2012-05-01

    Medial olivocochlear (MOC) neurons originate in the superior olivary complex and project to the cochlea, where they act to reduce the effects of noise masking and protect the cochlea from damage. MOC neurons respond to sound via a reflex pathway; however, in this pathway the cochlear nucleus cell type that provides input to MOC neurons is not known. We investigated whether multipolar cells of the ventral cochlear nucleus have projections to MOC neurons by labeling them with injections into the dorsal cochlear nucleus. The projections of one type of labeled multipolar cell, planar neurons, were traced into the ventral nucleus of the trapezoid body, where they were observed terminating on MOC neurons (labeled in some cases by a second cochlear injection of FluoroGold). These terminations formed what appear to be excitatory synapses, i.e., containing small, round vesicles and prominent postsynaptic densities. These data suggest that cochlear nucleus planar multipolar neurons drive the MOC neuron's response to sound.

  12. Acute upregulation of neuronal mitochondrial type-1 cannabinoid receptor and it's role in metabolic defects and neuronal apoptosis after TBI.

    Science.gov (United States)

    Xu, Zhen; Lv, Xiao-Ai; Dai, Qun; Ge, Yu-Qing; Xu, Jie

    2016-08-02

    Metabolic defects and neuronal apoptosis initiated by traumatic brain injury (TBI) contribute to subsequent neurodegeneration. They are all regulated by mechanisms centered around mitochondrion. Type-1 cannabinoid receptor (CB1) is a G-protein coupled receptor (GPCR) enriched on neuronal plasma membrane. Recent evidences point to the substantial presence of CB1 receptors on neuronal mitochondrial outer membranes (mtCB1) and the activation of mtCB1 influences aerobic respiration via inhibiting mitochondrial cyclic adenosine monophosphate (cAMP)/protein kinase A (PKA)/complex I pathway. The expression and role of neuronal mtCB1 under TBI are unknown. Using TBI models of cultured neurons, wild type and CB1 knockout mice, we found mtCB1 quickly upregulated after TBI. Activation of mtCB1 promoted metabolic defects accompanied with ATP shortage but protected neurons from apoptosis. Selective activation of plasma membrane CB1 showed no effects on neuronal metabolism and apoptosis. Activation of mtCB1 receptors inhibited mitochondrial cAMP/PKA/complex I and resulted in exacerbated metabolic defects accompanied with a higher ratio of ATP reduction to oxygen consumption decrease as well as neuronal apoptosis. Further research found the remarkable accumulation of protein kinase B (AKT) on neuronal mitochondria following TBI and the activation of mtCB1 upregulated mitochondrial AKT/complex V activity. Upregulation of mitochondrial AKT/complex V activity showed anti-apoptosis effects and alleviated ATP shortage in metabolic defects. Taken together, we have identified mtCB1 quickly upregulate after TBI and a dual role the mtCB1 might play in metabolic defects and neuronal apoptosis initiated by TBI: the inhibition of mitochondrial cAMP/PKA/complex I aggravates metabolic defects, energy insufficiency as well as neuronal apoptosis, but the coactivation of mitochondrial AKT/complex V mitigates energy insufficiency and neuronal apoptosis.

  13. Neuron division or enucleation.

    Science.gov (United States)

    Sotnikov, O S; Laktionova, A A; Solovieva, I A; Krasnova, T V

    2010-10-01

    The classical Bielschowsky-Gross neurohistological method was used to reproduce all the morphological phenomena interpreted by many authors as signs of neuron division, budding, and fission. It is suggested that these signs are associated with the effects of enucleation, which occurs in many cells of other tissue types in response to a variety of chemical and physical treatments. Studies were performed using neurons isolated from the mollusk Lymnaea stagnalis and exposed in tissue culture to the actin microfilament inhibitor cytochalasin B. Phase contrast time-lapse video recording over periods of 4-8 h demonstrated nuclear displacement, ectopization, and budding, to the level of almost complete fission of the neuron body. This repeats the pattern seen in static fixed preparations in "normal" conditions and after different experimental treatments. Budding of the cytoplasm was also sometimes seen at the early stages of the experiments. Control experiments in which cultured neurons were exposed to the solvent for cytochalasin B, i.e., dimethylsulfoxide (DMSO), did not reveal any changes in neurons over a period of 8 h. We take the view that the picture previously interpreted as neuron division and fission can be explained in terms of the inhibition of actin microfilaments, sometimes developing spontaneously in cells undergoing individual metabolic changes preventing the maintenance of cytoskeleton stability.

  14. NeuronBank: A Tool for Cataloging Neuronal Circuitry.

    Science.gov (United States)

    Katz, Paul S; Calin-Jageman, Robert; Dhawan, Akshaye; Frederick, Chad; Guo, Shuman; Dissanayaka, Rasanjalee; Hiremath, Naveen; Ma, Wenjun; Shen, Xiuyn; Wang, Hsui C; Yang, Hong; Prasad, Sushil; Sunderraman, Rajshekhar; Zhu, Ying

    2010-01-01

    The basic unit of any nervous system is the neuron. Therefore, understanding the operation of nervous systems ultimately requires an inventory of their constituent neurons and synaptic connectivity, which form neural circuits. The presence of uniquely identifiable neurons or classes of neurons in many invertebrates has facilitated the construction of cellular-level connectivity diagrams that can be generalized across individuals within a species. Homologous neurons can also be recognized across species. Here we describe NeuronBank.org, a web-based tool that we are developing for cataloging, searching, and analyzing neuronal circuitry within and across species. Information from a single species is represented in an individual branch of NeuronBank. Users can search within a branch or perform queries across branches to look for similarities in neuronal circuits across species. The branches allow for an extensible ontology so that additional characteristics can be added as knowledge grows. Each entry in NeuronBank generates a unique accession ID, allowing it to be easily cited. There is also an automatic link to a Wiki page allowing an encyclopedic explanation of the entry. All of the 44 previously published neurons plus one previously unpublished neuron from the mollusc, Tritonia diomedea, have been entered into a branch of NeuronBank as have 4 previously published neurons from the mollusc, Melibe leonina. The ability to organize information about neuronal circuits will make this information more accessible, ultimately aiding research on these important models.

  15. NeuronBank: a tool for cataloging neuronal circuitry

    Directory of Open Access Journals (Sweden)

    Paul S Katz

    2010-04-01

    Full Text Available The basic unit of any nervous system is the neuron. Therefore, understanding the operation of nervous systems ultimately requires an inventory of their constituent neurons and synaptic connectivity, which form neural circuits. The presence of uniquely identifiable neurons or classes of neurons in many invertebrates has facilitated the construction of cellular-level connectivity diagrams that can be generalized across individuals within a species. Homologous neurons can also be recognized across species. Here we describe NeuronBank.org, a web-based tool that we are developing for cataloging, searching, and analyzing neuronal circuitry within and across species. Information from a single species is represented in an individual branch of NeuronBank. Users can search within a branch or perform queries across branches to look for similarities in neuronal circuits across species. The branches allow for an extensible ontology so that additional characteristics can be added as knowledge grows. Each entry in NeuronBank generates a unique accession ID, allowing it to be easily cited. There is also an automatic link to a Wiki page allowing an encyclopedic explanation of the entry. All of the 44 previously published neurons plus one previously unpublished neuron from the mollusc, Tritonia diomedea, have been entered into a branch of NeuronBank as have 4 previously published neurons from the mollusc, Melibe leonina. The ability to organize information about neuronal circuits will make this information more accessible, ultimately aiding research on these important models.

  16. NeuronBank: A Tool for Cataloging Neuronal Circuitry

    Science.gov (United States)

    Katz, Paul S.; Calin-Jageman, Robert; Dhawan, Akshaye; Frederick, Chad; Guo, Shuman; Dissanayaka, Rasanjalee; Hiremath, Naveen; Ma, Wenjun; Shen, Xiuyn; Wang, Hsui C.; Yang, Hong; Prasad, Sushil; Sunderraman, Rajshekhar; Zhu, Ying

    2010-01-01

    The basic unit of any nervous system is the neuron. Therefore, understanding the operation of nervous systems ultimately requires an inventory of their constituent neurons and synaptic connectivity, which form neural circuits. The presence of uniquely identifiable neurons or classes of neurons in many invertebrates has facilitated the construction of cellular-level connectivity diagrams that can be generalized across individuals within a species. Homologous neurons can also be recognized across species. Here we describe NeuronBank.org, a web-based tool that we are developing for cataloging, searching, and analyzing neuronal circuitry within and across species. Information from a single species is represented in an individual branch of NeuronBank. Users can search within a branch or perform queries across branches to look for similarities in neuronal circuits across species. The branches allow for an extensible ontology so that additional characteristics can be added as knowledge grows. Each entry in NeuronBank generates a unique accession ID, allowing it to be easily cited. There is also an automatic link to a Wiki page allowing an encyclopedic explanation of the entry. All of the 44 previously published neurons plus one previously unpublished neuron from the mollusc, Tritonia diomedea, have been entered into a branch of NeuronBank as have 4 previously published neurons from the mollusc, Melibe leonina. The ability to organize information about neuronal circuits will make this information more accessible, ultimately aiding research on these important models. PMID:20428500

  17. Protective effect of Mrh-aFGF on the neurons in ventral tegmental area of rats with Parkinson’ s disease%Mrh-aFGF对帕金森病大鼠中脑腹侧被盖区神经元的保护

    Institute of Scientific and Technical Information of China (English)

    肖春苟; 蒋威; 李力强; 邹锦慧; 沈伟哉

    2016-01-01

    Objepctive To explore the protective effect of modified recombinant human aFGF ( Mrh-aFGF) on the neurons in ventral tegmental area of rats with Parkinson’ s disease ( PD) . Methods The 54 SD rats were ramdomly divided into the control group,the model group and the treatment group,and there were 18 rats in each group. PD rats of the model group and the treatment group were induced by in-jecting 6-OHDA into the left substantia nigra compacta ( SNC) and ventral tegmental area ( VTA) to build the PD model. Rats in the treat-ment group were given Mrh-aFGF injection after lateral ventricle injection,and the behavioral changes of the rats were detected after apomor-phine injection. The morphologic features and pathological changes of neurons in the ventral tegmental area were observed by Nissl’ s staining and electronic microscope. Results Compared to the right VTA of PD rats,the number of neurons in left side ( the injured side) decreased significantly in the model group(P<0. 05). In the treatment group,the structure of left (the injured side) VTA was markedly improved and the number of neurons was increased one week,two weeks and four weeks after operation compared with the model group (P<0. 05). The neurons in the VTA of the model group were found to have karyopyknosis,endoplasmic reticulum,degranulation,mitochondria swelling,cristae disappear,pre-synaptic and post-synaptic membranes swelling,and synaptic cleft disappear. In the treatment group,the ultrastructure of the neurons in the VTA,such as nuclei,mitochondria,synaptic structure,kept well compared to the model group. Conclusion Mrh-aFGF could protect the neurons in the ventral tegmental area from the loss and improve the ultrastructure of the neurons of PD rats.%目的:探讨重组人改构体酸性成纤维细胞生长因子( Mrh-aFGF)对帕金森病( PD)大鼠中脑腹侧被盖区神经元病变的影响。方法将54只SPF级雄性SD大鼠随机分为对照组、模型组和治疗组,每组18只。6-

  18. The Endogenous Hallucinogen and Trace Amine N,N-Dimethyltryptamine (DMT) Displays Potent Protective Effects against Hypoxia via Sigma-1 Receptor Activation in Human Primary iPSC-Derived Cortical Neurons and Microglia-Like Immune Cells.

    Science.gov (United States)

    Szabo, Attila; Kovacs, Attila; Riba, Jordi; Djurovic, Srdjan; Rajnavolgyi, Eva; Frecska, Ede

    2016-01-01

    N,N-dimethyltryptamine (DMT) is a potent endogenous hallucinogen present in the brain of humans and other mammals. Despite extensive research, its physiological role remains largely unknown. Recently, DMT has been found to activate the sigma-1 receptor (Sig-1R), an intracellular chaperone fulfilling an interface role between the endoplasmic reticulum (ER) and mitochondria. It ensures the correct transmission of ER stress into the nucleus resulting in the enhanced production of antistress and antioxidant proteins. Due to this function, the activation of Sig-1R can mitigate the outcome of hypoxia or oxidative stress. In this paper, we aimed to test the hypothesis that DMT plays a neuroprotective role in the brain by activating the Sig-1R. We tested whether DMT can mitigate hypoxic stress in in vitro cultured human cortical neurons (derived from induced pluripotent stem cells, iPSCs), monocyte-derived macrophages (moMACs), and dendritic cells (moDCs). Results showed that DMT robustly increases the survival of these cell types in severe hypoxia (0.5% O2) through the Sig-1R. Furthermore, this phenomenon is associated with the decreased expression and function of the alpha subunit of the hypoxia-inducible factor 1 (HIF-1) suggesting that DMT-mediated Sig-1R activation may alleviate hypoxia-induced cellular stress and increase survival in a HIF-1-independent manner. Our results reveal a novel and important role of DMT in human cellular physiology. We postulate that this compound may be endogenously generated in situations of stress, ameliorating the adverse effects of hypoxic/ischemic insult to the brain.

  19. The endogenous hallucinogen and trace amine N,N-dimethyltryptamine (DMT displays potent protective effects against hypoxia via sigma-1 receptor activation in human primary iPSC-derived cortical neurons and microglia-like immune cells

    Directory of Open Access Journals (Sweden)

    Attila Szabo

    2016-09-01

    Full Text Available N,N-dimethyltryptamine (DMT is a potent endogenous hallucinogen present in the brain of humans and other mammals. Despite extensive research, its physiological role remains largely unknown. Recently, DMT has been found to activate the sigma-1 receptor (Sig-1R, an intracellular chaperone fulfilling an interface role between the endoplasmic reticulum (ER and mitochondria. It ensures the correct transmission of ER stress into the nucleus resulting in the enhanced production of antistress and antioxidant proteins. Due to this function, the activation of Sig-1R can mitigate the outcome of hypoxia or oxidative stress. In this paper we aimed to test the hypothesis that DMT plays a neuroprotective role in the brain by activating the Sig-1R. We tested whether DMT can mitigate hypoxic stress in in vitro cultured human cortical neurons (derived from induced pluripotent stem cells, and in monocyte-derived macrophages and dendritic cells. Here we report that DMT robustly increases the survival of these cell types in severe hypoxia (0.5% O2 through the Sig-1R. Furthermore, this phenomenon is associated with the decreased expression and function of the alpha subunit of the hypoxia-inducible factor 1 (HIF-1 suggesting that DMT-mediated Sig-1R activation may alleviate hypoxia-induced cellular stress and increase survival in a HIF-1-independent manner. Our results reveal a novel and important role of DMT in human cellular physiology. We postulate that this compound may be endogenously generated in situations of stress, ameliorating the adverse effects of hypoxic/ischemic insult to the brain.

  20. Neurons of human nucleus accumbens

    Directory of Open Access Journals (Sweden)

    Sazdanović Maja

    2011-01-01

    Full Text Available Background/Aim. Nucleus accumbens is a part of the ventral striatum also known as a drug active brain region, especially related with drug addiction. The aim of the study was to investigate the Golgi morphology of the nucleus accumbens neurons. Methods. The study was performed on the frontal and sagittal sections of 15 human brains by the Golgi Kopsch method. We classified neurons in the human nucleus accumbens according to their morphology and size into four types: type I - fusiform neurons; type II - fusiform neurons with lateral dendrite, arising from a part of the cell body; type III - pyramidal-like neuron; type IV - multipolar neuron. The medium spiny neurons, which are mostly noted regarding to the drug addictive conditions of the brain, correspond to the type IV - multipolar neurons. Results. Two regions of human nucleus accumbens could be clearly recognized on Nissl and Golgi preparations each containing different predominant neuronal types. Central part of nucleus accumbens, core region, has a low density of impregnated neurons with predominant type III, pyramidal-like neurons, with spines on secondary branches and rare type IV, multipolar neurons. Contrary to the core, peripheral region, shell of nucleus, has a high density of impregnated neurons predominantly contained of type I and type IV - multipolar neurons, which all are rich in spines on secondary and tertiary dendritic branches. Conclusion. Our results indicate great morphological variability of human nucleus accumbens neurons. This requires further investigations and clarifying clinical significance of this important brain region.

  1. 吡格列酮对缺血-再灌注损伤大鼠皮质神经元的保护作用%Protective effect of pioglitazone and the role on the cultured cortical neuron after ischemia-reperfusion injury

    Institute of Scientific and Technical Information of China (English)

    黄昭; 王思荣; 刘继云

    2009-01-01

    Objective To explore the protective effect of proliferator activated receptor-γ (PPAR-γ)activator pioglitazone on the expression of inflammatory cytokines in cultured cortical neurons after ischemia-reperfusion injury and its mechanism. Method The ischemie-reperfusion model was established by deprivating both glucose an oxygen in medium and then gave them back. Medium or that with pioglitazone was added at the beginning of reperfusion. The MTT values of neurons were determined in control or treatment groups, ANOVA was used to detect the expression of PPAR-γ. The expression of tumor necrosis factors-α(TNF-α) and interleukin-lβ(IL-lβ) were detected by Western Blotting. Results Compared to control group, the markedly reduction of MTT values and enhanced expression of PPAR-γ, TNF-a and IL-1β was observed in the ischemia-reperfusion neurons (P < 0.05). After they were treated by pioglitazone, the reduction of MTT values and enhanced expression of TNF-a and IL-1β were prominently reversed by the further activation of PPAR-γ ( P < 0.05). Conclusions Treatment of PPAR-γ activator pioglitazone has protective effect on neurons after ischemia-reperfusion injury. Its mechanism may be associated with the inhibition of inflammation after injury.%目的 探讨过氧化物酶增值物激活受体-γ(PPAR-γ)及其激活剂噻唑烷二酮类药物-吡格列酮(pioglitazone)对缺血.再灌注损伤大鼠皮质神经元肿瘤坏死因子(TNF-α)、白介素(IL-1β)表达的影响.方法 采用原代培养的皮质神经元,通过去除培养液中的糖和氧,模拟缺血缺氧,恢复糖氧供给模拟再灌注.再灌注时分别加用普通培养或含吡格列酮20 μmol/L培养基分别再培养6 h后,以上各组及正常细胞组均采用RT-PCR检测PPAR-γ mRNA表达,MTT法检测细胞活性,同时免疫蛋白印记法检测TNF-α,IL-β蛋白表达.统计学采用单因素方差分析进行统计处理.结果 与正常细胞对照组相比,缺血-再灌注组细

  2. Neuronal survival in the brain: neuron type-specific mechanisms.

    Science.gov (United States)

    Pfisterer, Ulrich; Khodosevich, Konstantin

    2017-03-02

    Neurogenic regions of mammalian brain produce many more neurons that will eventually survive and reach a mature stage. Developmental cell death affects both embryonically produced immature neurons and those immature neurons that are generated in regions of adult neurogenesis. Removal of substantial numbers of neurons that are not yet completely integrated into the local circuits helps to ensure that maturation and homeostatic function of neuronal networks in the brain proceed correctly. External signals from brain microenvironment together with intrinsic signaling pathways determine whether a particular neuron will die. To accommodate this signaling, immature neurons in the brain express a number of transmembrane factors as well as intracellular signaling molecules that will regulate the cell survival/death decision, and many of these factors cease being expressed upon neuronal maturation. Furthermore, pro-survival factors and intracellular responses depend on the type of neuron and region of the brain. Thus, in addition to some common neuronal pro-survival signaling, different types of neurons possess a variety of 'neuron type-specific' pro-survival constituents that might help them to adapt for survival in a certain brain region. This review focuses on how immature neurons survive during normal and impaired brain development, both in the embryonic/neonatal brain and in brain regions associated with adult neurogenesis, and emphasizes neuron type-specific mechanisms that help to survive for various types of immature neurons. Importantly, we mainly focus on in vivo data to describe neuronal survival specifically in the brain, without extrapolating data obtained in the PNS or spinal cord, and thus emphasize the influence of the complex brain environment on neuronal survival during development.

  3. Kappe neurons, a novel population of olfactory sensory neurons

    Science.gov (United States)

    Ahuja, Gaurav; Nia, Shahrzad Bozorg; Zapilko, Veronika; Shiriagin, Vladimir; Kowatschew, Daniel; Oka, Yuichiro; Korsching, Sigrun I.

    2014-02-01

    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 report here a novel, fourth olfactory sensory neuron population in zebrafish, which we named kappe neurons for their characteristic shape. Kappe neurons are identified by their Go-like immunoreactivity, and show a distinct spatial distribution within the olfactory epithelium, similar to, but significantly different from that of crypt neurons. Furthermore, kappe neurons project to a single identified target glomerulus within the olfactory bulb, mdg5 of the mediodorsal cluster, whereas crypt neurons are known to project exclusively to the mdg2 glomerulus. Kappe neurons are negative for established markers of ciliated, microvillous and crypt neurons, but appear to have microvilli. Kappe neurons constitute the fourth type of olfactory sensory neurons reported in teleost fishes and their existence suggests that encoding of olfactory stimuli may require a higher complexity than hitherto assumed already in the peripheral olfactory system.

  4. Stochastic neuron models

    CERN Document Server

    Greenwood, Priscilla E

    2016-01-01

    This book describes a large number of open problems in the theory of stochastic neural systems, with the aim of enticing probabilists to work on them. This includes problems arising from stochastic models of individual neurons as well as those arising from stochastic models of the activities of small and large networks of interconnected neurons. The necessary neuroscience background to these problems is outlined within the text, so readers can grasp the context in which they arise. This book will be useful for graduate students and instructors providing material and references for applying probability to stochastic neuron modeling. Methods and results are presented, but the emphasis is on questions where additional stochastic analysis may contribute neuroscience insight. An extensive bibliography is included. Dr. Priscilla E. Greenwood is a Professor Emerita in the Department of Mathematics at the University of British Columbia. Dr. Lawrence M. Ward is a Professor in the Department of Psychology and the Brain...

  5. 感觉神经(元)对失神经骨骼肌超微结构保护作用的实验研究%Experimental study of the influence of sensory nerve (neuron) protection on the ultrastructure of denervated skeletal muscles

    Institute of Scientific and Technical Information of China (English)

    王欢; 李继峰; 钟慈声; 顾玉东

    2001-01-01

    Objective To observe the influence of sensory nerve (neuron)protection on the ultrastructure of denervated skeletal muscle. Methods 60 SD rats were randomly divided into 10 groups, with 6 each. Group A of simple complete denervation of biceps brachii served as control. Groups B ~ E were experimental groups which standed for complete denervation with sensory nerve implantation, complete denervation with sensory nerve “ baby - sitting”, complete denervation with dorsal root ganglia implantation, and complete denervation with implantation of preganglionically avulsed sensory nerve respectively. 1 month and 3 months postoperatively, electron microscopic observation of the muscles was done. Results Compared to the control, less degenerated nucleus, minor mitochondria edema and sarcoplasmic reticulum enlargement, higher capillary/myofiber ratio, less interstitial fibroblast and collagen fibers, better oriented myomere and myofilament were seen in the experimental groups. Conclusions Sensory nerves or neurons can protect the ultrastructure of denervated skeletal muscle.%目的观察感觉神经(元)对失神经骨骼肌超微结构的保护作用。方法60只SD大鼠,按手术先后顺序随机分成10组,每组6只。A组(对照组):肱二头肌完全失神经支配。B~E组(实验组):B组为失神经支配加感觉神经种植组,C组为失神经支配加感觉神经寄养组,D组为失神经支配加背根神经节种植组,E组为节前撕脱的感觉神经种植组。术后1、3个月取材,各组又分为二个时间组。用透射电镜观察肌肉超微结构的变化。结果与对照组相比,各实验组肌肉退变核数少、线粒体肿胀及肌质网扩张程度轻、毛细血管/肌纤维数比值大、间质胶原纤维和成纤维细胞少、肌丝肌节排列整齐。结论感觉神经(元)对失神经骨骼肌超微结构有保护作用。

  6. H2对大鼠全脑缺血再灌注损伤后海马CA1区神经元及树突棘的保护作用%Protective effect of hydrogen gas on neurons and dendritic spines of hippocampus CA1 region in rats after global cerebral ischemia/reperfusion injury

    Institute of Scientific and Technical Information of China (English)

    谭永星; 袁楠楠; 夏裕宁; 张鑫磊; 梁维; 魏佑震

    2016-01-01

    Objective To explore the protective effect of in-taking high concentration hydrogen gas on neurons and dendritic spines in hippocampus CA1 region of rats after globe cerebral ischemia/reperfusion (I/R) injury and its mechanism.Methods Four-vessel occlusion (4VO) was used to establish the models of global cerebral I/R injury in rats.One hundred and twenty healthy male Sprague-Dawley rats were randomly divided into 3 groups using a random number table:sham-operated group (inhaled 67% N2 and 67% O2,n=40),model group (inhaled 67% N2 and 67% O2 during reperfusion,n=40),and treatment group (inhaled 67% H2 and 67% O2 during reperfusion,n=40).After 72 h,5 and 9 d reperfusion,neuron-specific nuclear (NeuN) protein expression in the pyramidal neurons of the hippocampal CA1 region was detected with immumohistochemical staining and the positive cells were counted.And the contents of superoxide dismutase (SOD) and malondialdehyde (MDA) in serum were tested with colorimetry.Water maze test was used to measure the spatial orientation and memory function and Golgi staining to detect the number of dendritic spines in neurons 9 d after reperfusion.Results (1) Immunohistochemical staining of NeuN results showed that as compared with those in the model group,the neurons ofhippocampus CA1 region were significantly closer to normal with relatively intact structure,and the number of positive neurons was significantly increased in the treatment group 72 h,5 d,and 9 d after reperfusion (P<0.05).With the reperfusion time being prolonged,the number of NeuN stained positive neurons at different time points of reperfusion in model group was gradually decreased (P<0.05),and the numeric of the NeuN stained positive neurons at different time points of reperfusion in treatment group was slightly declined without significant difference (P>0.05).(2) The serum SOD activity in the treatment group was significantly higher than that in the model group and sham-operated group (P<0

  7. 星形胶质细胞通过谷胱甘肽保护MN9D细胞抵抗鱼藤酮所致氧化应激%Astrocytes protect MN9D neuronal cells against rotenone-induced oxidative stress by a glutathione-dependent mechanism

    Institute of Scientific and Technical Information of China (English)

    曹倩; 魏灵荣; 鲁玲玲; 赵春礼; 赵焕英; 杨慧

    2007-01-01

    星形胶质细胞维持神经元微环境,给予营养和代谢支持,并调节其对损伤的反应.鱼藤酮特异阻断线粒体复合物I,长期暴露于鱼藤酮可能增加患帕金森病的几率,并引起帕金森综合征.然而,星形胶质细胞在鱼藤酮所致多巴胺能神经元损伤过程中的作用尚无报道.本研究采用多巴胺能神经元细胞系MN9D细胞模型,将经过或未经过星形胶质细胞条件培养基处理的MN9D细胞暴露于不同浓度的鱼藤酮中,用计数法测生长曲线,MTT法测细胞活性,DCFH染色流式细胞仪测氧化应激水平,比色法测还原型谷胱甘肽含量.结果显示,MN9D细胞在条件和普通培养基培养条件下生长曲线无明显差别;鱼藤酮浓度依赖性地降低细胞活性;不同浓度鱼藤酮作用24、48h后,经条件培养基处理的细胞其活性显著高于普通培养基培养的细胞;不同浓度的条件培养基都有保护作用,纯的条件培养基保护作用稍弱;预先24h条件培养基处理或同时给予鱼藤酮和条件培养基处理都有保护作用,鱼藤酮作用12h后再给予条件培养基则无保护作用;经条件培养基处理的细胞氧化应激水平降低;另外,条件培养基提高了细胞内还原型谷胱甘肽含量,缓解了鱼藤酮所致的谷胱甘肽耗竭.结果提示,星形胶质细胞可保护MN9D细胞抵抗鱼藤酮所致的氧化应激,还原型谷胱甘肽可能参与了该保护过程.%Astrocytes maintain homeostasis of neuronal microenvironment, provide metabolic and trophic support to neurons and modulate neuronal responses to injury. Rotenone specifically inhibits mitochondrial complex I, and long exposure to rotenone may increase the risk for Parkinson's disease (PD) and cause Parkinsonism. However,little is known about the role of astrocytes in the process of rotenone-induced dopaminergic neuron injury. In order to investigate this issue, we used MN9D cells as a cell model of dopaminergic neurons and

  8. Neuronal survival in the brain: neuron type-specific mechanisms

    DEFF Research Database (Denmark)

    Pfisterer, Ulrich Gottfried; Khodosevich, Konstantin

    2017-01-01

    Neurogenic regions of mammalian brain produce many more neurons that will eventually survive and reach a mature stage. Developmental cell death affects both embryonically produced immature neurons and those immature neurons that are generated in regions of adult neurogenesis. Removal of substantial...... a particular neuron will die. To accommodate this signaling, immature neurons in the brain express a number of transmembrane factors as well as intracellular signaling molecules that will regulate the cell survival/death decision, and many of these factors cease being expressed upon neuronal maturation...... numbers of neurons that are not yet completely integrated into the local circuits helps to ensure that maturation and homeostatic function of neuronal networks in the brain proceed correctly. External signals from brain microenvironment together with intrinsic signaling pathways determine whether...

  9. Sun Protection

    Science.gov (United States)

    ... 100% UV ray protection (look for models that advertise both UVB and UVA protection). Use a broad- ... feeds Follow FDA on Twitter Follow FDA on Facebook View FDA videos on YouTube View FDA photos ...

  10. Ginsenoside Rb1 attenuates activated microglia-induced neuronal damage

    Institute of Scientific and Technical Information of China (English)

    Lining Ke; Wei Guo; Jianwen Xu; Guodong Zhang; Wei Wang; Wenhua Huang

    2014-01-01

    The microglia-mediated inlfammatory reaction promotes neuronal damage under cerebral isch-emia/hypoxia conditions. We therefore speculated that inhibition of hypoxia-induced microglial activation may alleviate neuronal damage. To test this hypothesis, we co-cultured ginsenoside Rb1, an active component of ginseng, and cortical neurons. Ginsenoside Rb1 protected neuronal morphology and structure in a single hypoxic culture system and in a hypoxic co-culture system with microglia, and reduced neuronal apoptosis and caspase-3 production. The protective effect was observable prior to placing in co-culture. Additionally, ginsenoside Rb1 inhibited levels of tumor necrosis factor-αin a co-culture system containing activated N9 microglial cells. Ginse-noside Rb1 also signiifcantly decreased nitric oxide and superoxide production induced by N9 microglia. Our ifndings indicate that ginsenoside Rb1 attenuates damage to cerebral cortex neu-rons by downregulation of nitric oxide, superoxide, and tumor necrosis factor-αexpression in hypoxia-activated microglia.

  11. Nanoresolution radiology of neurons

    Energy Technology Data Exchange (ETDEWEB)

    Wu, H.R.; Chen, S.T.; Chu, Y.S.; Conley, R.; Bouet, N.; Chien, C.C.; Chen, H.H.; Lin, C.H.; Tung, H.T.; Chen, Y.S.; Margaritondo, G.; Je, J.H.; Hwu, Y. (IP-Taiwan); (Ecole); (BNL); (POSTECH)

    2013-04-08

    We report recent advances in hard-x-ray optics - including record spatial resolution - and in staining techniques that enable synchrotron microradiology to produce neurobiology images of quality comparable to electron and visible microscopy. In addition, microradiology offers excellent penetration and effective three-dimensional detection as required for many neuron studies. Our tests include tomographic reconstruction based on projection image sets.

  12. Human embryonic stem cells for neuronal repair.

    Science.gov (United States)

    Ben-Hur, Tamir

    2006-02-01

    Human embryonic stem cells may serve as a potentially endeless source of transplantable cells to treat various neurologic disorders. Accumulating data have shown the therapeutic value of various neural precursor cell types in experimental models of neurologic diseases. Tailoring cell therapy for specific disorders requires the generation of cells that are committed to specific neural lineages. To this end, protocols were recently developed for the derivation of dopaminergic neurons, spinal motor neurons and oligodendrocytes from hESC. These protocols recapitulate normal development in culture conditions. However, a novel concept emerging from these studies is that the beneficial effect of transplanted stem cells is not only via cell replacement in damaged host tissue, but also by trophic and protective effects, as well as by an immunomodulatory effect that down-regulates detrimental brain inflammation.

  13. Exploring neuronal activity with photons

    Science.gov (United States)

    Bourdieu, Laurent; Léger, Jean-François

    2015-10-01

    The following sections are included: * Introduction * Information coding * Optical recordings of neuronal activity * Functional organization of the cortex at the level of a cortical column * Microarchitecture of a cortical column * Dynamics of neuronal populations * Outlook * Bibliography

  14. New findings on neuron development

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    @@ A mature neuron receives inputs from multiple dendrites and sends its output to other neurons via a single axon.This polarized morphology requires proper axonal/dendritic differentiation during development.

  15. Binary neuron with optical devices

    Science.gov (United States)

    Degeratu, Vasile; Degeratu, Ştefania; Şchiopu, Paul; Şchiopu, Carmen

    2009-01-01

    In this paper the authors present a model of binary neuron, a model of McCulloch-Pitts neuron with optical devices. This model of neuron can be implemented not only in the optic integrated circuits but also in the classic optical circuits it being cheap and immune not only into electromagnetic fields but also into any kind of radiation. The transfer speed of information through the neuron is very higher, it being limited only by the light speed from the received medium.

  16. Radiation induces acute alterations in neuronal function.

    Directory of Open Access Journals (Sweden)

    Peter H Wu

    Full Text Available Every year, nearly 200,000 patients undergo radiation for brain tumors. For both patients and caregivers the most distressing adverse effect is impaired cognition. Efforts to protect against this debilitating effect have suffered from inadequate understanding of the cellular mechanisms of radiation damage. In the past it was accepted that radiation-induced normal tissue injury resulted from a progressive reduction in the survival of clonogenic cells. Moreover, because radiation-induced brain dysfunction is believed to evolve over months to years, most studies have focused on late changes in brain parenchyma. However, clinically, acute changes in cognition are also observed. Because neurons are fully differentiated post-mitotic cells, little information exists on the acute effects of radiation on synaptic function. The purpose of our study was to assess the potential acute effects of radiation on neuronal function utilizing ex vivo hippocampal brain slices. The cellular localization and functional status of excitatory and inhibitory neurotransmitter receptors was identified by immunoblotting. Electrophysiological recordings were obtained both for populations of neuronal cells and individual neurons. In the dentate gyrus region of isolated ex vivo slices, radiation led to early decreases in tyrosine phosphorylation and removal of excitatory N-methyl-D-aspartate receptors (NMDARs from the cell surface while simultaneously increasing the surface expression of inhibitory gamma-aminobutyric acid receptors (GABA(ARs. These alterations in cellular localization corresponded with altered synaptic responses and inhibition of long-term potentiation. The non-competitive NMDAR antagonist memantine blocked these radiation-induced alterations in cellular distribution. These findings demonstrate acute effects of radiation on neuronal cells within isolated brain slices and open new avenues for study.

  17. 许旺细胞源神经营养因子对脊髓背根节感觉神经元的保护作用%Protective effect of Schwann cell-derived neurotrophic factor on sensory neurons in spinal dorsal root ganglia

    Institute of Scientific and Technical Information of China (English)

    刘黎军; 朱家恺; 王大平; 肖建德; 杨雷

    2006-01-01

    BACKGROUND: Schwann cell-derived neurotrophic factor is a bioactive protein isolated and purified from the kytoplasm of Schwann cell. It can obviously maintain the survival of spinal cord anterior horn motor neuron and promote the regeneration of peripheral nerve.OBJECTIVE: To observe the protective effect of Schwann cell-derived neurotrophic factor on the high injury of peripheral nerve-induced apoptosis of sensory neurons in spinal dorsal root ganglia.DESIGN: Randomized and controlled animal experiment.SETTING: Shenzhen Second People's Hospital.MATERIALS: Totally 30 3-week-old SD infant rats, of clean grade and either gender, were used in this experiment. They were randomly divided into neurotrophic factor group and control group with 15 rats in each one.Left sides of the animals in both two groups were set as normal sides and right sides as injured sides.METHODS: This experiment was carried out at the Experimental Animal Center, Medical College of Sun Yat-sen University from May 2003 to July 2003. ① L4.5 nerve root high-mutilation animal models were developed on the rats in two groups. Proximal nerve stump was connected with silicone tube. According to grouping, 60 mg/L Schwann cell-derived neurotrophic factors and 20 μL normal saline were injected into the silicone tubes respectively. Two ends of silicone tube were enveloped with vaseline.② Sample collecting was conducted at postoperative 4 weeks, survival rate and morphological change of sensory neurons in dorsal root ganglia of injured nerve was observed.MAIN OUTCOME MEASURES: ① Gross observation of sciatic nerve regeneration at injured side of the rats in two groups ② Survival of sensory neurons in dorsal root ganglia ③ Morphological change of sensory neurons in dorsal root ganglia.RESULTS: All the 30 rats entered the stage of result analysis. ① Gross observation of sciatic nerve regeneration: In the neurotrophic factor group,nerve new born axon grew along silicone tube, with 1cm in length

  18. Rhythm dynamics of complex neuronal networks with mixed bursting neurons

    Institute of Scientific and Technical Information of China (English)

    Lü Yong-Bing; Shi Xia; Zheng Yan-Hong

    2013-01-01

    The spatiotemporal order and rhythm dynamics of a complex neuronal network with mixed bursting neurons are studied in this paper.A quantitative characteristic,the width factor,is introduced to describe the rhythm dynamics of an individual neuron,and the average width factor is used to characterize the rhythm dynamics of a neuronal network.An r parameter is introduced to denote the ratio of the short bursting neurons in the network.Then we investigate the effect of the ratio on the rhythm dynamics of the neuronal network.The critical value of r is derived,and the neurons in the network always remain short bursting when the r ratio is larger than the critical value.

  19. Bacteria activate sensory neurons that modulate pain and inflammation

    NARCIS (Netherlands)

    Chiu, Isaac M.; Heesters, Balthasar A.; Ghasemlou, Nader; Von Hehn, Christian A.; Zhao, Fan; Tran, Johnathan; Wainger, Brian; Strominger, Amanda; Muralidharan, Sriya; Horswill, Alexander R.; Wardenburg, Juliane Bubeck; Hwang, Sun Wook; Carroll, Michael C.; Woolf, Clifford J.

    2013-01-01

    Nociceptor sensory neurons are specialized to detect potentially damaging stimuli, protecting the organism by initiating the sensation of pain and eliciting defensive behaviours. Bacterial infections produce pain by unknown molecular mechanisms, although they are presumed to be secondary to immune a

  20. Muscle-Derived GDNF: A Gene Therapeutic Approach for Preserving Motor Neuron Function in ALS

    Science.gov (United States)

    2015-08-01

    neural progenitor cells (hNPC) secreting GDNF to the spinal of SOD1G93A rats protects motor neurons from degeneration. Supported by the California...56S-61S. 12. Suzuki, M., et al., GDNF secreting human neural progenitor cells protect dying motor neurons, but not their projection to muscle, in a rat ...into astrocytes, and no tumor formation following transplantation into the spinal cord of immunocompromised rats . Neuroreport, 2013. 21. Emborg, M.E

  1. 苦参碱对缺血性脑中风小鼠神经元及星形胶质细胞的保护作用%Protective effects of matrine on Neurons and Astrocytes in focal ischemia induced by pMCAO in mouse

    Institute of Scientific and Technical Information of China (English)

    程丽艳; 沈佳; 沈陶冶; 史红

    2012-01-01

    目的:观察苦参碱(Matrine)对缺血性脑中风小鼠的神经保护作用及对缺氧缺糖诱导的神经元和星形胶质细胞损伤的减轻作用,并初步探讨可能的作用机制.方法:采用原代培养小鼠大脑皮层神经元及星形胶质细胞缺氧缺糖模型(Oxygen and glucose deprivation,OGD),MTT法和测定乳酸脱氢酶(LDH)观察Matrine对OGD神经元及星形胶质细胞的损伤是否有减轻作用;建立小鼠永久性大脑中动脉阻塞(Permanent middle cerebral artery occlusion,pMCAO)模型,观察Matrine 10 min、1h、3h及6h四个不同时间点给药后,脑梗死面积和神经症状的改善情况及其分子机制是否与抑制神经元及星形胶质细胞NF-κB信号通路有关.结果:经OGD诱导后,原代培养小鼠大脑皮层神经元及星形胶质细胞活力明显下降,与OGD模型组比较,给予Matrine(50 μmol/L)干预后,神经元及星形胶质细胞的存活率明显提高(P<0.01);与此同时,OGD可使小鼠大脑皮层星形胶质细胞LDH漏出量增高(P<0.01),Matrine(50 μmol/L)与模型组比较,LDH漏出量明显降低(P<0.01);Matrine(37.5 mg/kg) 10 min、1h两个给药时间点的脑梗死面积与模型组比较明显减少(P<0.01);与模型组比较,Martine 10 min、1h两个给药时间点术后24 h的神经症状评分明显降低(P<0.01);Matrine可降低pMCAO缺血区IκBα与IKK蛋白的表达水平(P<0.01,P<0.05),同时降低细胞核NF-κB蛋白的表达(P<0.01).结论:Matrine可通过直接保护神经元及星形胶质细胞改善缺血性脑中风症状,其作用时间窗可能在发病1h以内,Matrine保护作用可能与NF-κB信号通路有关.%AIM: To investigate the protective effects of matrine on neurons and astrocytes in focal ischemia induced by permanent middle cer-ebral artery occlusion (pMCAO) in mouse and explore the possible mechanism. METHODS: MTT and LDH assays were used to assess the protective effects of matrine in primary culture of neurons

  2. 灵芝孢子粉对杏仁核点燃模型大鼠神经元的功能性保护作用及机制%The effect of Reishi Mushroom Powder on protection of amygdala lighting model rat neurons and its mechanism

    Institute of Scientific and Technical Information of China (English)

    张继国; 王艺; 张静

    2012-01-01

    Purpose To observe the IL-6 and TNF-α level of amygdala lighting model rat neurons after treatment by Reishi Mushroom Powder and to explore the effect of Reishi Mushroom Powder on epilepsy and its mechanism. Methods 24 male rats were made as amygdala lighting model,and divided into three groups, including Reishi Mushroom Powder( dosing group) , physiological saline( control group) ,and phenobarbital(positive group). All of the treatment was given by gastric lavage for 2 weeks. After treatment, IL-6 and TNF-α level of the hippocampus tissue cells were detected. Results The IL-6 level and TNF-α level of dosing group and positive group were significantly lower than those of control group ( P 0. 05). Conclusion Reishi Mushroom Powder could dramatically reduce the cytokine of neurons caused by epilepsy, and had a sedative and protection function for nervous system.%目的 观察灵芝孢子粉治疗后杏仁核点燃模型大鼠神经元IL-6和TNF-α mRNA表达水平的变化,探讨灵芝孢子粉对癫痫的作用及机制.方法 雄性大鼠24只,制备杏仁核点燃模型后,分为灵芝孢子粉组、阴性对照组(生理盐水)、阳性对照组(苯巴比妥).治疗2周后,检测海马组织IL-6和TNF-α mRNA表达情况.结果 灵芝孢子粉组及阳性对照组TNF-α、IL-6的mRNA表达均较阴性对照组明显减低(P<0.05),灵芝孢子粉组与阳性对照组之间TNF-α、IL-6的mRNA表达无明显差异(P>0.05).结论 灵芝孢子粉能够影响癫痫发病过程中的细胞因子,并对神经系统具有镇静和保护功能.

  3. Neuronal synchrony 

    OpenAIRE

    Buzsáki, Gyorgy

    2010-01-01

    1. Neuronal synchrony: metabolic and wiring costs of excitatory and inhibitory systems The major part of the brain’s energy budget (~ 60-80%) is devoted to its communication activities. While inhibition is critical to brain function, relatively little attention has been paid to its metabolic costs. Understanding how inhibitory interneurons contribute to brain energy consumption (brain work) is not only of interest in understanding a fundamental aspect of brain function but also in understandi...

  4. Micropatterning neuronal networks.

    Science.gov (United States)

    Hardelauf, Heike; Waide, Sarah; Sisnaiske, Julia; Jacob, Peter; Hausherr, Vanessa; Schöbel, Nicole; Janasek, Dirk; van Thriel, Christoph; West, Jonathan

    2014-07-01

    Spatially organised neuronal networks have wide reaching applications, including fundamental research, toxicology testing, pharmaceutical screening and the realisation of neuronal implant interfaces. Despite the large number of methods catalogued in the literature there remains the need to identify a method that delivers high pattern compliance, long-term stability and is widely accessible to neuroscientists. In this comparative study, aminated (polylysine/polyornithine and aminosilanes) and cytophobic (poly(ethylene glycol) (PEG) and methylated) material contrasts were evaluated. Backfilling plasma stencilled PEGylated substrates with polylysine does not produce good material contrasts, whereas polylysine patterned on methylated substrates becomes mobilised by agents in the cell culture media which results in rapid pattern decay. Aminosilanes, polylysine substitutes, are prone to hydrolysis and the chemistries prove challenging to master. Instead, the stable coupling between polylysine and PLL-g-PEG can be exploited: Microcontact printing polylysine onto a PLL-g-PEG coated glass substrate provides a simple means to produce microstructured networks of primary neurons that have superior pattern compliance during long term (>1 month) culture.

  5. Effect of deep brain stimulation on substantia nigra neurons in a rat model of Parkinson's disease

    Institute of Scientific and Technical Information of China (English)

    WU Sheng-tian; MA Yu; ZHANG Kai; ZHANG Jian-guo

    2012-01-01

    Background Parkinson's disease(PD)is a common neurodegenerative disease,which occurs mainly in the elderly.Recent studies have demonstrated that apoptosis plays an important role in the occurrence and development of PD.Subthalamic nucleus deep brain stimulation(STN-DBS)has been recognized as an effective treatment for PD.Recent clinical observations have shown that STN-DBS was able to delay early PD progression,and experiments in animal models have also demonstrated a protective effect of STN-DBS on neurons.However,the correlation between the neuron-protective effect of STN-DBS and the progression of substantia nigra pars compacta(SNc)neuronal apoptosis is still unknown.The aim of this study was to investigate the protective effect and potential mechanism of STN-DBS on SNc neurons in PD rats.Methods After the establishment of a PD rat model by unilateral/2-point injection of 6-hydroxydopamine in the medial forebrain bundle of the brain,DBS by implanting electrodes in the STN was administered.Behavioral changes were observed,and morphological changes of SNc neurons were analyzed by Nissl staining and DNA in situ end-labeling.Through extracellular recording of single neuron discharges and microelectrophoresis,the causes of and changes in SNc excitability during STN-DBS were analyzed,and the protective effect and potential mechanism of action of STN-DBS on SNc neurons in PD rats was investigated.Results SNc neuron apoptosis was significantly decreased(P<0.05)in the stimulation group,compared with the sham stimulation PD group.Spontaneous discharges of SNc neurons were observed in normal rats and PD model rats,and the mean frequency of spontaneous discharges of SNc neurons in normal rats((40.65±11.08)Hz)was higher than that of residual SNc neurons in PD rats((36.71±9.23)Hz).Electrical stimulation of the STN in rats was associated with elevated excitation in unilateral SNc neurons.However,administering the gamma-aminobutyric acid receptor blocker

  6. Trophic factors as modulators of motor neuron physiology and survival: implications for ALS therapy

    Directory of Open Access Journals (Sweden)

    Luis B Tovar-y-Romo

    2014-02-01

    Full Text Available Motor neuron physiology and development depend on a continuous and tightly regulated trophic support from a variety of cellular sources. Trophic factors guide the generation and positioning of motor neurons during every stage of the developmental process. As well, they are involved in axon guidance and synapse formation. Even in the adult spinal cord an uninterrupted trophic input is required to maintain neuronal functioning and protection from noxious stimuli. Among the trophic factors that have been demonstrated to participate in motor neuron physiology are vascular endothelial growth factor (VEGF, glial-derived neurotrophic factor (GDNF, ciliary neurotrophic factor (CNTF and insulin-like growth factor 1 (IGF-1. Upon binding to membrane receptors expressed in motor neurons or neighboring glia, these trophic factors activate intracellular signaling pathways that promote cell survival and have protective action on motor neurons, in both in vivo and in vitro models of neuronal degeneration. For these reasons these factors have been considered a promising therapeutic method for amyotrophic lateral sclerosis (ALS and other neurodegenerative diseases, although their efficacy in human clinical trials have not yet shown the expected protection. In this review we summarize experimental data on the role of these trophic factors in motor neuron function and survival, as well as their mechanisms of action. We also briefly discuss the potential therapeutic use of the trophic factors and why these therapies may have not been yet successful in the clinical use.

  7. Neurotoxicity of isoniazid and its metabolites in cultures of mouse dorsal root ganglion neurons and hybrid neuronal cell line.

    Science.gov (United States)

    Sanfeliu, C; Wright, J M; Kim, S U

    1999-12-01

    Isoniazid (INH) is one of the anti-tuberculosis drugs widely prescribed for patients since the early 1950s. It is relatively nontoxic but some patients develop peripheral neuropathy attributed to a disturbance of vitamin B6 metabolism. Some isoniazid metabolites are hepatotoxic but little is known about their neurotoxic property. Isoniazid and its metabolites including acetylisoniazid, acetylhydrazine, diacetylhydrazine, isonicotinic acid and hydrazine were examined for their potential neurotoxic effects in cultured mouse dorsal root ganglion (DRG) neurons and mouse neuroblastoma x DRG neuron hybrid cell line N18D3. Isoniazid did not cause neurotoxicity at exposures up to 7 days. Hydrazine was found to be the most toxic metabolite with LC50 values of 2.7 mM and 0.3 mM after 7 days of exposure in DRG neurons and N18D3 hybrid neurons, respectively. Other metabolites including acetylisoniazid, acetylhydrazine, diacetylhydrazine and isonicotinic acid had moderate to minor neurotoxic effects on N18D3 hybrid neurons. Pyridoxine, which is used in clinical practice to prevent or ameliorate the isoniazid-induced neuropathy, did not consistently reverse the neurotoxicity of any of the metabolites in the cell cultures, but some interaction with hydrazine cannot be ruled out. Pyridoxine itself was found to be neurotoxic both in DRG neurons and N18D3 hybrid neurons, in agreement with human peripheral sensory neuropathy caused by prolonged overdosage. The enzymes catalase and superoxide dismutase and the antioxidant agent selenium showed some protection against hydrazine neurotoxicity, suggesting an involvement of the generation of reactive oxygen species in the pathogenesis of isoniazid neuropathy. Both mouse DRG neurons and N18D3 mouse hybrid neurons were shown to be useful culture systems for elucidating the neurotoxicity mechanisms of agents causing sensory neuropathies and general neurotoxic effects in the nervous system.

  8. Brainstem neurons survive the identical ischemic stress that kills higher neurons: insight to the persistent vegetative state.

    Directory of Open Access Journals (Sweden)

    C Devin Brisson

    Full Text Available Global ischemia caused by heart attack, pulmonary failure, near-drowning or traumatic brain injury often damages the higher brain but not the brainstem, leading to a 'persistent vegetative state' where the patient is awake but not aware. Approximately 30,000 U.S. patients are held captive in this condition but not a single research study has addressed how the lower brain is preferentially protected in these people. In the higher brain, ischemia elicits a profound anoxic depolarization (AD causing neuronal dysfunction and vasoconstriction within minutes. Might brainstem nuclei generate less damaging AD and so be more resilient? Here we compared resistance to acute injury induced from simulated ischemia by 'higher' hippocampal and striatal neurons versus brainstem neurons in live slices from rat and mouse. Light transmittance (LT imaging in response to 10 minutes of oxygen/glucose deprivation (OGD revealed immediate and acutely damaging AD propagating through gray matter of neocortex, hippocampus, striatum, thalamus and cerebellar cortex. In adjacent brainstem nuclei, OGD-evoked AD caused little tissue injury. Whole-cell patch recordings from hippocampal and striatal neurons under OGD revealed sudden membrane potential loss that did not recover. In contrast brainstem neurons from locus ceruleus and mesencephalic nucleus as well as from sensory and motor nuclei only slowly depolarized and then repolarized post-OGD. Two-photon microscopy confirmed non-recoverable swelling and dendritic beading of hippocampal neurons during OGD, while mesencephalic neurons in midbrain appeared uninjured. All of the above responses were mimicked by bath exposure to 100 µM ouabain which inhibits the Na+/K+ pump or to 1-10 nM palytoxin which converts the pump into an open cationic channel. Therefore during ischemia the Na+/K+ pump of higher neurons fails quickly and extensively compared to naturally resilient hypothalamic and brainstem neurons. The selective survival

  9. Negotiating Protection

    DEFF Research Database (Denmark)

    Bille, Mikkel

    strategies are confirming their efficacy, and act as material anchors for negotiating Bedouin identities in response to a rapid transformation from nomadic pastoralists to sedentary wageworkers. The tensions surrounding the materiality of protection, along with the role of the past in the present is further...... strategies are entangled in cultural, religious, and national identities. Using ethnographic methods, I investigate protection against selected risks: harm from evil eyes, violation of domestic sanctity, and cultural heritage dilapidation. Protection against these risks is examined through studies...... investigated through the contested public representations of Ammarin culture, along with a detailed study of the process leading to the protection of Bedouin culture by UNESCO Intangible Cultural Heritage. The overall conclusion of this research is that negotiating efficacious protection against perceived...

  10. 松果菊苷对鱼藤酮诱导的大鼠帕金森病模型黑质多巴胺能神经元的选择性保护作用%Selective protection of nigral dopaminergic neurons by echinacoside in a rat model of Parkinson disease induced by rotenone

    Institute of Scientific and Technical Information of China (English)

    封新影; 朱敏; 张琦琪; 陈依萍; 李文伟

    2012-01-01

    OBJECTIVE: To observe the protective effects of echinacoside on rotenone-induced damages in rats.METHODS:Healthy male Sprague-Dawley rats,weighing from 200 to 220 g,were randomly divided into five groups with 20 rats in each group:control group,rotenone group and echinacoside groups of low,medium and high doses (20,40 and 80 mg/(kg·d)).Rats in the rotenone group were injected intraperitoneally for four weeks with rotenone (2.75 mg/(kg·d)),dissolved into dimethyl sulfoxide; rats in the control group were injected intraperitoneally with dimethyl sulfoxide daily,and rats in the echinacoside groups received daily intraperitoneal injection of rotenone along with echinacoside gastric perfusion for four weeks.Modified neurological severity score was used to evaluate neurobehavior of the animals; dopaminergic neurons in substantia nigra were observed by immunochemical method and dopamine concentration in striatum was determined by a fluorescence spectrophotometer.Biomarkers of liver and kidney damage were also measured.RESULTS:In the rotenone group,the rats suffered from severe neurological disability (P<0.01),and the number of dopaminergic neurons in substantia nigra and dopamine concentration in striatum were decreased (P<0.05) compared with the normal control group; levels of the biomarkers for evaluating liver and kidney damage were increased (P<0.05).In the echinacoside groups,the neurological disability and the loss of dopaminergic neurons in substantia nigra were suppressed and dopamine concentrations in striatum were increased (P<0.05),but the liver and kidney damage was not improved (P>0.05).CONCLUSION:Rotenone causes severe damages to dopaminergic