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Sample records for chronic hypoxic mouse

  1. Mechanical properties and reactivity of vessels in isolated perfused lungs of chronically hypoxic rats.

    Science.gov (United States)

    Emery, C J; Bee, D; Barer, G R

    1981-11-01

    1. Chronically hypoxic rats kept in 10% (v/v) O2 for 3--6 weeks, were compared with littermate control rats. Pulmonary vascular resistance, measured from the slope of the pressure-flow relationship in isolated lungs perfused with blood of normal packed cell volume was higher in chronically hypoxic than control rats even during normoxia. 2. Chronically hypoxic rats weighed less than control rats but their pulmonary vascular volume, measured with labelled albumin was similar to control rats. This, together with evidence that the number of precapillary vessels is not reduced, does not suggest a large reduction in the vascular bed in chronic hypoxia. 3. A greater vasodilator action of isoprenaline and adenosine in chronically hypoxic than control lungs suggested a higher normoxic vascular tone. This higher tone was not the sole cause of increased resistance in chronically hypoxic lungs, since maximal vasodilatation did not reduce resistance to control levels. The chief cause was probably encroachment of new muscle on the vascular lumen of small vessels. 4. Pulmonary arterial compliance was reduced in chronically hypoxic lungs. 5. Reactivity of vessels to ventilation hypoxia, over a wide range of oxygen tension, to angiotensin II (ANG II) and to adenosine 5'-triphosphate (ATP) was significantly greater in chronically hypoxic than control lungs, but thresholds to these stimuli were not reduced. PMID:7285503

  2. Effect of breviscapine on fractalkine expression in chronic hypoxic rats

    Institute of Scientific and Technical Information of China (English)

    CHEN Xiao-ju; CHENG De-yun; YANG Li; XIA Xiu-qiong; GUAN Jian

    2006-01-01

    @@ Fractalkine (FKN) is the only known chemokine that fulfils the dual functions of an adhesive molecule and a soluble chemoattractant.1 FKN expression was reported increase in lungs of patients with severe pulmonary arterial hypertension,2 suggesting that FKN may participate in pathogenesis of pulmonary hypertension.Breviscapine is a flavonoid extracted from Erigeron breviscapus (Vant.) Hand. Mazz. Breviscapine can prevent the development of hypoxic pulmonary hypertension3 but the mechanism is unknown. This study evaluated the role of FKN in the pathogenesis of hypoxic pulmonary hypertension and the effect of breviscapine on FKN in hypoxic pulmonary hypertension.

  3. The Effect of Ginkgo Biloba Extract on Hypoxic Fraction of C3H Mouse Fibrosarcoma

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Chul Koo; Yi, Chun Ja; Ha, Sung Whan; Park, Charn Il [Seoul National University College of Medicine, Seoul (Korea, Republic of)

    1995-09-15

    Purpose : To investigate the effect of Ginkgo biloba extract (GBE) on hypoxic cell fraction and metabolic status in fibrosarcoma (FSa II) of C3H mouse. Materials and Methods : Fibrosarcoma (Fsa II), 6mm in diameter, growing in the right hind leg muscle of C3H mouse was used for estimation of hypoxic cell fraction using comparison of TCD{sub 50}. Radiation was given one hour after administration of GBE (100 mg/Kg, i.p.) with or without priming dose of GBE (100 mg/Kg, i.p.) given 24 hours earlier. Radiation was also given under air breathing condition or clamp hypoxia without GBE as controls. {sup 31}P NMR spectroscopy was performed before and one hour after administration of GBE with or without priming dose of GBE. Results : TCD{sub 50/120's} were 81.7(77.7-86.0) Gy when irradiated under clamped hypoxia, 69.6 (66.8-72.5) Gy under air breathing condition,67.5(64.1-71.1) Gy with a single dose of GBE (100 mg/kg) given one hour before irradiation, and 62.2(59.1-65.5) Gy with two doses of GBE given at 25 hours and one hour before irradiation. The hypoxic cell fractions, estimated from TCD50/120's were 1.6% under air breathing condition, 7.2% after single dose of GBE, and 2.7% after two doses of GBE. Metabolic status of tumor, probably by increasing the blood flow and delivery of oxygen and nutrients, resulting in increased radiosensitivity of tumor.

  4. The Effect of Ginkgo Biloba Extract on Hypoxic Fraction of C3H Mouse Fibrosarcoma

    International Nuclear Information System (INIS)

    Purpose : To investigate the effect of Ginkgo biloba extract (GBE) on hypoxic cell fraction and metabolic status in fibrosarcoma (FSa II) of C3H mouse. Materials and Methods : Fibrosarcoma (Fsa II), 6mm in diameter, growing in the right hind leg muscle of C3H mouse was used for estimation of hypoxic cell fraction using comparison of TCD50. Radiation was given one hour after administration of GBE (100 mg/Kg, i.p.) with or without priming dose of GBE (100 mg/Kg, i.p.) given 24 hours earlier. Radiation was also given under air breathing condition or clamp hypoxia without GBE as controls. 31P NMR spectroscopy was performed before and one hour after administration of GBE with or without priming dose of GBE. Results : TCD50/120's were 81.7(77.7-86.0) Gy when irradiated under clamped hypoxia, 69.6 (66.8-72.5) Gy under air breathing condition,67.5(64.1-71.1) Gy with a single dose of GBE (100 mg/kg) given one hour before irradiation, and 62.2(59.1-65.5) Gy with two doses of GBE given at 25 hours and one hour before irradiation. The hypoxic cell fractions, estimated from TCD50/120's were 1.6% under air breathing condition, 7.2% after single dose of GBE, and 2.7% after two doses of GBE. Metabolic status of tumor, probably by increasing the blood flow and delivery of oxygen and nutrients, resulting in increased radiosensitivity of tumor

  5. Combination of nicotinamide and hyperthermia to eliminate radioresistant chronically and acutely hypoxic tumor cells

    International Nuclear Information System (INIS)

    The interaction among nicotinamide, radiation, and heat was studied in vivo using a C3H mouse mammary carcinoma grown in the feet of CDF1 mice. Response following local tumor treatment was assessed by tumor control and regrowth delay. Nicotinamide (1000 mg/kg i.p.) produced maximal radiosensitization when injected 30 min to 2 h before irradiation [enhancement ratios (ERs), 1.2-1.5]. Radiation damage was also increased by heating tumors (43.5 degrees C for 60 min) 4 h after irradiation (ERs = 1.6-2.6). This combined radiation and heat treatment was enhanced by nicotinamide but the effect depended on the assay procedure, such that although a significant increase was observed with the tumor control assay, only a slight increase was seen using regrowth delay as the end point. The development of moist desquamation in normal feet was used to estimate skin damage after irradiation. Nicotinamide and heat both resulted in a small yet significant increase in skin damage (ERs less than 1.2 and 1.1, respectively). A combined treatment resulted in a greater ER of 1.7, but when compared to the tumor response it still gave a therapeutic gain. A histological fluorescent staining technique was used to assess functional tumor vasculature at two periods in time separated by 20 min. Under normal conditions 7.7% of the vessels in this tumor were functional at one time but not the other. This value was reduced to 2.8% after nicotinamide administration. Since these fluctuations in blood flow can result in acute hypoxia we conclude that while heat eliminates chronically hypoxic tumor cells, nicotinamide probably removes the presence of acute hypoxia

  6. Lung angiotensin converting enzyme activity in chronically hypoxic rats.

    OpenAIRE

    Kay, J M; Keane, P. M.; Suyama, K L; Gauthier, D.

    1985-01-01

    A study was carried out to test the hypothesis that the reduced lung angiotensin converting enzyme (ACE) activity which occurs in chronic hypoxia is related to the development of pulmonary hypertension rather than to hypoxia per se. Right ventricular mean systolic pressure (Prvs, mm Hg) and ACE activity (nmol/mg protein/min) in lung tissue homogenates were measured in seven groups of four rats placed in a hypobaric chamber (380 mm Hg; 51 kPa) for two to 24 days. Identical measurements were ma...

  7. RELAXANT EFFECTS OF VASOACTIVE INTESTINAL PEPTIDE ON PULMONARY ARTERY IN CHRONICALLY HYPOXIC RATS

    Institute of Scientific and Technical Information of China (English)

    陈玉玲; 罗慰慈; 蔡英年

    1996-01-01

    The object of this study is to investigate the effect of VIP on pulmonary artery of chronically hypoxic rats. It was shown that chronic hypoxla depressed significantly pulmnonary artery relaxation induced by VIP as compared with those of control (Pchronic hypoxxia, and chronic hypoxiamay inhibit directly the soluble guanylate cyclase in vascular smooth muscle cells invioved in synthesis of cGMP and thus reduced the sensitivity and reactivity of pulmonary artery to VIP.

  8. General anesthetics inhibit erythropoietin induction under hypoxic conditions in the mouse brain.

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    Tomoharu Tanaka

    Full Text Available BACKGROUND: Erythropoietin (EPO, originally identified as a hematopoietic growth factor produced in the kidney and fetal liver, is also endogenously expressed in the central nervous system (CNS. EPO in the CNS, mainly produced in astrocytes, is induced under hypoxic conditions in a hypoxia-inducible factor (HIF-dependent manner and plays a dominant role in neuroprotection and neurogenesis. We investigated the effect of general anesthetics on EPO expression in the mouse brain and primary cultured astrocytes. METHODOLOGY/PRINCIPAL FINDINGS: BALB/c mice were exposed to 10% oxygen with isoflurane at various concentrations (0.10-1.0%. Expression of EPO mRNA in the brain was studied, and the effects of sevoflurane, halothane, nitrous oxide, pentobarbital, ketamine, and propofol were investigated. In addition, expression of HIF-2α protein was studied by immunoblotting. Hypoxia-induced EPO mRNA expression in the brain was significantly suppressed by isoflurane in a concentration-dependent manner. A similar effect was confirmed for all other general anesthetics. Hypoxia-inducible expression of HIF-2α protein was also significantly suppressed with isoflurane. In the experiments using primary cultured astrocytes, isoflurane, pentobarbital, and ketamine suppressed hypoxia-inducible expression of HIF-2α protein and EPO mRNA. CONCLUSIONS/SIGNIFICANCE: Taken together, our results indicate that general anesthetics suppress activation of HIF-2 and inhibit hypoxia-induced EPO upregulation in the mouse brain through a direct effect on astrocytes.

  9. Quantitative studies of the vasculature of the carotid body in the chronically hypoxic rat

    OpenAIRE

    Clarke, J.A.; Daly, M. B.; Marshall, J. M.; Ead, H. W.; Hennessy, E M

    2000-01-01

    The carotid bodies of rats made chronically hypoxic by breathing 12% O2 in a normobaric chamber (inspired PO2 91 mmHg) were compared with those of controls. Serial 5-µm sections of the organs were examined using an interactive image analysis system. The total volume of the carotid bodies was increased by 64%. The total vascular volume rose by 103% and was likely due to an increase in size of the large vessels (>12 µm lumen diameter) because the small vessel (5-12 µm lumen diameter) volume ...

  10. Effects of Neonatal Hypoxic-Ischemic Injury and Hypothermic Neuroprotection on Neural Progenitor Cells in the Mouse Hippocampus.

    Science.gov (United States)

    Kwak, Minhye; Lim, Sanghee; Kang, Eunchai; Furmanski, Orion; Song, Hongjun; Ryu, Yun Kyoung; Mintz, C David

    2015-01-01

    Neonatal hypoxic-ischemic injury (HI) results in widespread cerebral encephalopathy and affects structures that are essential for neurocognitive function, such as the hippocampus. The dentate gyrus contains a reservoir of neural stem and progenitor cells (NSPCs) that are critical for postnatal development and normal adult function of the hippocampus, and may also facilitate the recovery of function after injury. Using a neonatal mouse model of mild-to-moderate HI and immunohistochemical analysis of NSPC development markers, we asked whether these cells are vulnerable to HI and how they respond to both injury and hypothermic therapy. We found that cleaved caspase-3 labeling in the subgranular zone, where NSPCs are located, is increased by more than 30-fold after HI. The population of cells positive for both proliferating cell nuclear antigen and nestin (PCNA+Nes+), which represent primarily actively proliferating NSPCs, are acutely decreased by 68% after HI. The NSPC population expressing NeuroD1, a marker for NSPCs transitioning to become fate-committed neural progenitors, was decreased by 47%. One week after HI, there was a decrease in neuroblasts and immature neurons in the dentate gyrus, as measured by doublecortin (DCX) immunolabeling, and at the same time PCNA+Nes+ cell density was increased by 71%. NSPCs expressing Tbr2, which identifies a highly proliferative intermediate neural progenitor population, increased by 107%. Hypothermia treatment after HI partially rescues both the acute decrease in PCNA+Nes+ cell density at 1 day after injury and the chronic loss of DCX immunoreactivity and reduction in NeuroD1 cell density measured at 1 week after injury. Thus, we conclude that HI causes an acute loss of dentate gyrus NSPCs, and that hypothermia partially protects NSPCs from HI. PMID:26087836

  11. Influence of Ginkgo Biloba extract on beta-secretase in rat hippocampal neuronal cultures following chronic hypoxic and hypoglycemic conditions

    Institute of Scientific and Technical Information of China (English)

    Xueneng Guan; Fuling Yan

    2008-01-01

    BACKGROUND: Preparation of Ginkgo leaf has been widely used to improve cognitive deficits and dementia, in particular in Alzheimer's disease patients. However, the precise mechanism of action of Ginkgo leaf remains unclear.OBJECTIVE: To explore the effect of Ginkgo Biloba extract (Egb761), Ginaton, on β-secretase expression in rat hippocampal neuronal cultures following chronic hypoxic and hypoglycemic conditions.DESIGN, TIME AND SETTNG: Completely by randomized, grouping study. The experiment was performed at the Laboratory of Molecular Imaging, Southeast University between August 2006 and August 2007.MATERIALS: A total of 128 Wistar rats aged 24 hours were selected, and hippocampal neurons were harvested for primary cultures.METHODS: On day 7, primary hippocampal neuronal cultures were treated with Egb761 (0, 25, 50, 100, 150, and 200 μ g/mL) under hypoxic/hypoglycemic or hypoglycemic culture conditions for 12, 24, and 36 hours, respectively. Hippocampal neurons cultured in primary culture medium served as control.MAIN OUTCOME MEASURES: Cell viability was assayed using 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT); fluorescence detection of β-secretase activity was performed; Western Blot was used to measure β -secretase expression.RESULTS: Cell viability under hypoxic/hypoglycemic or hypoglycemic culture conditions was significantly less than control cells (P 25 μ g/mL Egb761 induced greater cell viability (P 0.05). Α -secretase activity was increased after 12 hours in hypoxic/hypoglycemic culture (P 0.05). Β -secretase activity was greater after 12, 24, and 36 hours in hypoxic/hypoglycemic culture conditions, compared with control conditions (P < 0.05). Β-secretase activity was significantly decreased in neurons treated with Egb761 for 12, 24, or 36 hours, compared with the hypoxic/hypoglycemic group (P < 0.05).β-secretase protein expression was significantly up-regulated in neurons cultured in hypoxic/hypoglycemic conditions for

  12. Hypoxic preconditioning involves system Xc- regulation in mouse neural stem cells.

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    Sims, Brian; Clarke, Melinda; Francillion, Ludwig; Kindred, Elijah; Hopkins, Elana Shuford; Sontheimer, Harald

    2012-03-01

    In animals, hypoxic preconditioning has been used as a form of neuroprotection. The exact mechanism involved in neuroprotective hypoxic preconditioning has not been described, yet could be valuable for possible neuroprotective strategies. The overexpression of the cystine-glutamate exchanger, system Xc-, has been demonstrated as being neuroprotective (Shih, Erb et al. 2006). Here, using immunohistochemistry, we demonstrate that C57BL/6 mice exposed to hypoxia showed an increase in system Xc- expression, with the highest level of intensity in the hippocampus. Western Blot analysis also showed an almost 2-fold increase in system Xc- protein in hypoxia-exposed versus control mice. The mRNA for the regulatory subunit of system Xc-, xCT, and the xCT/actin ratio were also increased under hypoxic conditions. Experiments using hypoxia-inducible factor (HIF-1α) siRNA showed a statistically significant decrease in HIF-1α and system Xc- expression. Under hypoxic conditions, system Xc- activity, as determined by cystine uptake, increased 2-fold. Importantly, hypoxic preconditioning was attenuated in neural stem cells by pharmacological inhibition of system Xc- activity with S4-carboxyphenylglycine. These data provide the first evidence of hypoxic regulation of the cystine glutamate exchanger system Xc-.

  13. Effect of L-arginine on renal blood flow in normal subjects and patients with hypoxic chronic obstructive pulmonary disease.

    OpenAIRE

    Howes, T. Q.; Keilty, S. E.; Maskrey, V. L.; Deane, C. R.; Baudouin, S. V.; Moxham, J

    1996-01-01

    BACKGROUND: L-arginine is the precursor of endothelium derived nitric oxide (NO) and increasing the available substrate may increase the production of NO. This has been shown by local infusion in peripheral vascular beds but there are few studies of the effects during systemic infusion. Renal vasoconstriction is known to be important in the pathogenesis of cor pulmonale in patients with hypoxic chronic obstructive pulmonary disease (COPD). The effects of a systemic infusion of L-arginine on r...

  14. Detection of hypoxic cells in a C3H mouse mammary carcinoma using the comet assay.

    OpenAIRE

    Olive, P. L.; Horsman, M R; C. Grau; Overgaard, J.

    1997-01-01

    The comet assay was used to estimate radiobiological hypoxic fraction across a full range of tumour oxygenations in C3H mammary tumours implanted into the feet of female CDF1 mice. Tumours were either clamped before irradiation or mice were allowed to breath air, 100% oxygen, carbogen or carbon monoxide for 5-35 min before and during exposure to 15 Gy. For the alkaline comet assay, tumours were excised after irradiation and individual tumour cells were analysed for DNA single-strand breaks. H...

  15. Effects of calcium-activated chloride channels on proliferation of pulmonary artery smooth muscle cells in rats under chronic hypoxic condition

    Institute of Scientific and Technical Information of China (English)

    Zhao Yang; Zhenxiang Zhang; Yongjian Xu; Tao Wang; Dan Ma; Tao Ye

    2008-01-01

    Objective: To investigate the effects of calcium-activated chloride (C1Ca) channels on proliferation of pulmonary artery smooth muscle cells(PASMCs) in rats under chronic hypoxic condition. Methods:The cultured PASMCs were placed under normoxic and chronic hypoxic conditions:The cells were observed by light and electron microscope; The cell cycles were observed by flow-cytometry; Immunocytochemistry staining was used to detect the expressions of PCNA, c-los and c-jun of PASMCs; Cytoplasmic free Ca2+ con-centration ([Ca2+]) in PASMCs was investigated by fluorescent quantitation using fluorospectrophotometer. Results:The PASMCs were contractile phenotype under normoxic conditions. Observation by transmission electron microscope: In kytoplasm of contractile phenotype cells, myofilament bundles were abundant and the content of cell organs such as Golgi's bodies were rare. The PASMCs were synthetic phenotype under chronic hypoxic condition. There were inereased free ribosomes, dilated rough endoplasmic reticulums, highly developed Golgi complexes, decreased or disappeared thick filaments and dense body in kytoplasm of synthetic phenotype cells. After NFA and IAA-94, the situations were reversed The number of S4,GzM PASMCs were significantly increased in chronic hypoxic condition; The NFA and IAA-94 were shown to significantly decrease them from (28.6±1.0)% to (16.0±1.6)% and the number of G0G1 PASMCs significantly increased from (71.4 ±1.9)% to (83.9±1.6)% (P< 0.01). In chronic hypoxic conditions, the expression of proliferating cell nucleus antigen was significantly increased; The NFA and IAA-94 were shown to significantly decrease it from (81±6)% to (27±7)%(P<0.01). The expression of c-los and c-jun were significantly increased in-chronic hypoxic conditions; The NFA and IAA-94 were shown to significantly decrease them from 0.15 ± 0.02, 0.32 ± 0.05 to 0.05 ± 0.01, 0.12±0.05, respectively (P< 0.01); Under chronic hypoxic conditions, [Ca2+]. Was increased

  16. Effect of chronic undernutrition on body mass and mechanical bone quality under normoxic and altitude hypoxic conditions.

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    Lezon, Christian; Bozzini, Clarisa; Agûero Romero, Alan; Pinto, Patricia; Champin, Graciela; Alippi, Rosa M; Boyer, Patricia; Bozzini, Carlos E

    2016-05-01

    Both undernutrition and hypoxia exert a negative influence on both growth pattern and bone mechanical properties in developing rats. The present study explored the effects of chronic food restriction on both variables in growing rats exposed to simulated high-altitude hypoxia. Male rats (n 80) aged 28 d were divided into normoxic (Nx) and hypoxic (Hx) groups. Hx rats were exposed to hypobaric air (380 mmHg) in decompression chambers. At T0, Nx and Hx rats were subdivided into four equal subgroups: normoxic control and hypoxic controls, and normoxic growth-restricted and hypoxic growth-restricted received 80 % of the amount of food consumed freely by their respective controls for a 4-week period. Half of these animals were studied at the end of this period (T4). The remaining rats in each group continued under the same environmental conditions, but food was offered ad libitum to explore the type of catch-up growth during 8 weeks. Structural bone properties (strength and stiffness) were evaluated in the right femur midshaft by the mechanical three-point bending test; geometric properties (length, cross-sectional area, cortical mass, bending cross-sectional moment of inertia) and intrinsic properties of the bone tissue (elastic modulus) were measured or derived from appropriate equations. Bone mineralisation was assessed by ash measurement of the left femur. These data indicate that the growth-retarded effects of diminished food intake, induced either by food restriction or hypoxia-related inhibition of appetite, generated the formation of corresponding smaller bones in which subnormal structural and geometric properties were observed. However, they seemed to be appropriate to the body mass of the animals and suggest, therefore, that the bones were not osteopenic. When food restriction was imposed in Hx rats, the combined effects of both variables were additive, inducing a further reduction of bone mass and bone load-carrying capacity. In all cases, the mechanical

  17. Fibroblast growth factor-2 induced by enriched environment enhances angiogenesis and motor function in chronic hypoxic-ischemic brain injury.

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    Jung Hwa Seo

    Full Text Available This study aimed to investigate the effects of enriched environment (EE on promoting angiogenesis and neurobehavioral function in an animal model of chronic hypoxic-ischemic (HI brain injury. HI brain damage was induced in seven day-old CD-1® mice by unilateral carotid artery ligation and exposure to hypoxia (8% O2 for 90 min. At six weeks of age, the mice were randomly assigned to either EE or standard cages (SC for two months. Rotarod, forelimb-use asymmetry, and grip strength tests were performed to evaluate neurobehavioral function. In order to identify angiogenic growth factors regulated by EE, an array-based multiplex ELISA assay was used to measure the expression in frontal cortex, striatum, and cerebellum. Among the growth factors, the expression of fibroblast growth factor-2 (FGF-2 was confirmed using western blotting. Platelet endothelial cell adhesion molecule-1 (PECAM-1 and α-smooth muscle actin (α-SMA were also evaluated using immunohistochemistry. As a result, mice exposed to EE showed significant improvements in rotarod and ladder walking performances compared to SC controls. The level of FGF-2 was significantly higher in the frontal cortex of EE mice at 8 weeks after treatment in multiplex ELISA and western blot. On the other hand, FGF-2 in the striatum significantly increased at 2 weeks after exposure to EE earlier than in the frontal cortex. Expression of activin A was similarly upregulated as FGF-2 expression pattern. Particularly, all animals treated with FGF-2 neutralizing antibody abolished the beneficial effect of EE on motor performance relative to mice not given anti-FGF-2. Immunohistochemistry showed that densities of α-SMA(+ and PECAM-1(+ cells in frontal cortex, striatum, and hippocampus were significantly increased following EE, suggesting the histological findings exhibit a similar pattern to the upregulation of FGF-2 in the brain. In conclusion, EE enhances endogenous angiogenesis and neurobehavioral functions

  18. KCa3.1 channel downregulation and impaired EDH-type relaxation in pulmonary arteries from chronic hypoxic rats

    DEFF Research Database (Denmark)

    Kroigaard, Christel; Kudryavtseva, Olga; Dalsgaard, Thomas;

    2013-01-01

    Calcium-activated potassium channels of small (K(Ca)2, SK) and intermediate (K(Ca)3.1, IK) conductance are involved in endothelium-dependent relaxation of pulmonary arteries. We hypothesized that the function and expression of K(Ca)2 and K(Ca)3.1 increase as a compensatory mechanism to counteract......-dependent relaxations, which were markedly reduced in arteries from chronically hypoxic rats compared with arteries from normoxic rats. The mRNA levels of K(Ca)2.3 and K(Ca)3.1 were unaltered, whereas K(Ca)2.3 protein expression was upregulated and K(Ca)3.1 protein expression downregulated in pulmonary arteries from.......3 channels. Since impaired EDH-type relaxation was accompanied by K(Ca)3.1 channel protein downregulation, these findings suggest that K(Ca)3.1 channels are important for the maintenance of EDH-type relaxation....

  19. Understanding Hypoxic Drive and the Release of Hypoxic Vasoconstriction.

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    Inkrott, Jon C

    2016-01-01

    Understanding the hypoxic drive and release of hypoxic vasoconstriction in the chronic obstructive pulmonary disease population can be somewhat confusing and misunderstood. Furthermore, the hypoxic drive theory is one in which there really is no scientific evidence to support and yet continues to prosper in every aspect of care in regard to the chronic lung patient, from prehospital all the way to intensive care unit and home care therapy. This subject review will hopefully enhance some understanding of what exactly goes on with these patients and the importance of providing oxygen when it is desperately needed.

  20. Expression profiling reveals novel hypoxic biomarkers in peripheral blood of adult mice exposed to chronic hypoxia.

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    Matias Mosqueira

    Full Text Available Hypoxia induces a myriad of changes including an increase in hematocrit due to erythropoietin (EPO mediated erythropoiesis. While hypoxia is of importance physiologically and clinically, lacunae exist in our knowledge of the systemic and temporal changes in gene expression occurring in blood during the exposure and recovery from hypoxia. To identify these changes expression profiling was conducted on blood obtained from cohorts of C57Bl-10 wild type mice that were maintained at normoxia (NX, exposed for two weeks to normobaric chronic hypoxia (CH or two weeks of CH followed by two weeks of normoxic recovery (REC. Using stringent bioinformatic cut-offs (0% FDR, 2 fold change cut-off, 230 genes were identified and separated into four distinct temporal categories. Class I contained 1 transcript up-regulated in both CH and REC; Class II contained 202 transcripts up-regulated in CH but down-regulated after REC; Class III contained 9 transcripts down-regulated both in CH and REC; Class IV contained 18 transcripts down-regulated after CH exposure but up-regulated after REC. Profiling was independently validated and extended by analyzing expression levels of selected genes as novel biomarkers from our profile (e.g. spectrin alpha-1, ubiquitin domain family-1 and pyrroline-5-carboxylate reductase-1 by performing qPCR at 7 different time points during CH and REC. Our identification and characterization of these genes define transcriptome level changes occurring during chronic hypoxia and normoxic recovery as well as novel blood biomarkers that may be useful in monitoring a variety of physiological and pathological conditions associated with hypoxia.

  1. HIF-VEGF pathways are critical for chronic otitis media in Junbo and Jeff mouse mutants.

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    Michael T Cheeseman

    2011-10-01

    Full Text Available Otitis media with effusion (OME is the commonest cause of hearing loss in children, yet the underlying genetic pathways and mechanisms involved are incompletely understood. Ventilation of the middle ear with tympanostomy tubes is the commonest surgical procedure in children and the best treatment for chronic OME, but the mechanism by which they work remains uncertain. As hypoxia is a common feature of inflamed microenvironments, moderation of hypoxia may be a significant contributory mechanism. We have investigated the occurrence of hypoxia and hypoxia-inducible factor (HIF mediated responses in Junbo and Jeff mouse mutant models, which develop spontaneous chronic otitis media. We found that Jeff and Junbo mice labeled in vivo with pimonidazole showed cellular hypoxia in inflammatory cells in the bulla lumen, and in Junbo the middle ear mucosa was also hypoxic. The bulla fluid inflammatory cell numbers were greater and the upregulation of inflammatory gene networks were more pronounced in Junbo than Jeff. Hif-1α gene expression was elevated in bulla fluid inflammatory cells, and there was upregulation of its target genes including Vegfa in Junbo and Jeff. We therefore investigated the effects in Junbo of small-molecule inhibitors of VEGFR signaling (PTK787, SU-11248, and BAY 43-9006 and destabilizing HIF by inhibiting its chaperone HSP90 with 17-DMAG. We found that both classes of inhibitor significantly reduced hearing loss and the occurrence of bulla fluid and that VEGFR inhibitors moderated angiogenesis and lymphangiogenesis in the inflamed middle ear mucosa. The effectiveness of HSP90 and VEGFR signaling inhibitors in suppressing OM in the Junbo model implicates HIF-mediated VEGF as playing a pivotal role in OM pathogenesis. Our analysis of the Junbo and Jeff mutants highlights the role of hypoxia and HIF-mediated pathways, and we conclude that targeting molecules in HIF-VEGF signaling pathways has therapeutic potential in the treatment of

  2. Chronic Myeloid Leukemia (CML) Mouse Model in Translational Research.

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    Peng, Cong; Li, Shaoguang

    2016-01-01

    Chronic myeloid leukemia (CML) is a myeloproliferative disorder characterized by increased proliferation of granulocytic cells without the loss of their capability to differentiate. CML is a clonal disease, originated at the level of Hematopoietic Stem Cells with the Philadelphia chromosome resulting from a reciprocal translocation between the chromosomes 9 and 22t(9;22)-(q34;q11). This translocation produces a fusion gene known as BCR-ABL which acquires uncontrolled tyrosine kinase activity, constantly turning on its downstream signaling molecules/pathways, and promoting proliferation of leukemia cell through anti-apoptosis and acquisition of additional mutations. To evaluate the role of each critical downstream signaling molecule of BCR-ABL and test therapeutic drugs in vivo, it is important to use physiological mouse disease models. Here, we describe a mouse model of CML induced by BCR-ABL retrovirus (MSCV-BCR-ABL-GFP; MIG-BCR-ABL) and how to use this model in translational research.Moreover, to expand the application of this retrovirus induced CML model in a lot of conditional knockout mouse strain, we modified this vector to a triple gene coexpression vector in which we can co-express BCR-ABL, GFP, and a third gene which will be tested in different systems. To apply this triple gene system in conditional gene knockout strains, we can validate the CML development in the knockout mice and trace the leukemia cell following the GFP marker. In this protocol, we also describe how we utilize this triple gene system to prove the function of Pten as a tumor suppressor in leukemogenesis. Overall, this triple gene system expands our research spectrum in current conditional gene knockout strains and benefits our CML translational research. PMID:27150093

  3. Neuroprotective and anti-inflammatory effects of the flavonoid-enriched fraction AF4 in a mouse model of hypoxic-ischemic brain injury.

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    Paul G W Keddy

    Full Text Available We report here neuroprotective and anti-inflammatory effects of a flavonoid-enriched fraction isolated from the peel of Northern Spy apples (AF4 in a mouse of model of hypoxic-ischemic (HI brain damage. Oral administration of AF4 (50 mg/kg, once daily for 3 days prior to 50 min of HI completely prevented motor performance deficits assessed 14 days later that were associated with marked reductions in neuronal cell loss in the dorsal hippocampus and striatum. Pre-treatment with AF4 (5, 10, 25 or 50 mg/kg, p.o.; once daily for 3 days produced a dose-dependent reduction in HI-induced hippocampal and striatal neuron cell loss, with 25 mg/kg being the lowest dose that achieved maximal neuroprotection. Comparison of the effects of 1, 3 or 7 doses of AF4 (25 mg/kg; p.o. prior to HI revealed that at least 3 doses of AF4 were required before HI to reduce neuronal cell loss in both the dorsal hippocampus and striatum. Quantitative RT-PCR measurements revealed that the neuroprotective effects of AF4 (25 mg/kg; p.o.; once daily for 3 days in the dorsal hippocampus were associated with a suppression of HI-induced increases in the expression of IL-1β, TNF-α and IL-6. AF4 pre-treatment enhanced mRNA levels for pro-survival proteins such as X-linked inhibitor of apoptosis and erythropoietin following HI in the dorsal hippocampus and striatum, respectively. Primary cultures of mouse cortical neurons incubated with AF4 (1 µg/ml, but not the same concentrations of either quercetin or quercetin-3-O-glucose or its metabolites, were resistant to cell death induced by oxygen glucose deprivation. These findings suggest that the inhibition of HI-induced brain injury produced by AF4 likely involves a transcriptional mechanism resulting from the co-operative actions of various phenolics in this fraction which not only reduce the expression of pro-inflammatory mediators but also enhance pro-survival gene signalling.

  4. Evidence of hypoxic tolerance in weak upper airway muscle from young mdx mice.

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    Burns, David P; O'Halloran, Ken D

    2016-06-01

    Duchenne muscular dystrophy (DMD) is a genetic disease characterised by deficiency in the protein dystrophin. The respiratory system is weakened and patients suffer from sleep disordered breathing and hypoventilation culminating in periods of hypoxaemia. We examined the effects of an acute (6h) hypoxic stress on sternohyoid muscle function (representative pharyngeal dilator). 8 week old male, wild-type (WT; C57BL/10ScSnJ; n=18) and mdx (C57BL/10ScSn-Dmd(mdx)/J; n=16) mice were exposed to sustained hypoxia (FIO2=0.10) or normoxia. Muscle functional properties were examined ex vivo. Additional WT (n=5) and mdx (n=5) sternohyoid muscle was exposed to an anoxic challenge. Sternohyoid dysfunction was observed in mdx mice with significant reductions in force and power. Following exposure to the acute in vivo hypoxic stress, WT sternohyoid muscle showed evidence of functional impairment (reduced force, work and power). Conversely, mdx sternohyoid showed an apparent tolerance to the acute hypoxic stress. This tolerance was not maintained for mdx following a severe hypoxic stress. A dysfunctional upper airway muscle phenotype is present at 8 weeks of age in the mdx mouse, which may have implications for the control of airway patency in DMD. Hypoxic tolerance in mdx respiratory muscle is suggestive of adaptation to chronic hypoxia, which could be present due to respiratory morbidity. We speculate a role for hypoxia in mdx respiratory muscle morbidity. PMID:26691169

  5. A reliable method for intracranial electrode implantation and chronic electrical stimulation in the mouse brain

    OpenAIRE

    Jeffrey, Melanie; Lang, Min; Gane, Jonathan; Wu, Chiping; Burnham, W McIntyre; Zhang, Liang

    2013-01-01

    Background Electrical stimulation of brain structures has been widely used in rodent models for kindling or modeling deep brain stimulation used clinically. This requires surgical implantation of intracranial electrodes and subsequent chronic stimulation in individual animals for several weeks. Anchoring screws and dental acrylic have long been used to secure implanted intracranial electrodes in rats. However, such an approach is limited when carried out in mouse models as the thin mouse skul...

  6. Nitric oxide availability in deeply hypoxic crucian carp: acute and chronic changes and utilization of ambient nitrite reservoirs.

    Science.gov (United States)

    Hansen, Marie N; Gerber, Lucie; Jensen, Frank B

    2016-03-15

    Recent research suggest that anoxia-tolerant fish transfer extracellular nitrite into the tissues, where it is used for nitric oxide (NO) generation, iron-nitrosylation, and S-nitrosation of proteins, as part of the cytoprotective response toward prolonged hypoxia and subsequent reoxygenation. We hypothesized that crucian carp take up ambient nitrite and use it as a source of cellular NO availability during hypoxia. Fish were exposed for 1 day to normoxia (Po2 > 140 mmHg) and deep hypoxia (1 nitric oxide synthase-2 gene variant. The data support that ambient nitrite is taken up across the gills to be distributed via the blood to the tissues, particularly the heart, where it assists in cytoprotection and other functions. Cardiac nitrite was not elevated in acutely exposed fish, revealing that the response requires time. NO metabolite levels were higher during acute than chronic exposures, possibly caused by increased swimming activity and stress in acutely exposed fish.

  7. A New Mouse Model That Spontaneously Develops Chronic Liver Inflammation and Fibrosis

    Science.gov (United States)

    Fransén-Pettersson, Nina; Duarte, Nadia; Nilsson, Julia; Lundholm, Marie; Mayans, Sofia; Larefalk, Åsa; Hannibal, Tine D.; Hansen, Lisbeth; Schmidt-Christensen, Anja; Ivars, Fredrik; Cardell, Susanna; Palmqvist, Richard; Rozell, Björn

    2016-01-01

    Here we characterize a new animal model that spontaneously develops chronic inflammation and fibrosis in multiple organs, the non-obese diabetic inflammation and fibrosis (N-IF) mouse. In the liver, the N-IF mouse displays inflammation and fibrosis particularly evident around portal tracts and central veins and accompanied with evidence of abnormal intrahepatic bile ducts. The extensive cellular infiltration consists mainly of macrophages, granulocytes, particularly eosinophils, and mast cells. This inflammatory syndrome is mediated by a transgenic population of natural killer T cells (NKT) induced in an immunodeficient NOD genetic background. The disease is transferrable to immunodeficient recipients, while polyclonal T cells from unaffected syngeneic donors can inhibit the disease phenotype. Because of the fibrotic component, early on-set, spontaneous nature and reproducibility, this novel mouse model provides a unique tool to gain further insight into the underlying mechanisms mediating transformation of chronic inflammation into fibrosis and to evaluate intervention protocols for treating conditions of fibrotic disorders. PMID:27441847

  8. Resveratrol Neuroprotection in a Chronic Mouse Model of Multiple Sclerosis

    OpenAIRE

    Zoe eFonseca-Kelly; Mayssa eNassrallah; Jorge eUribe; Khan, Reas S.; Kimberly eDine; Mahasweta eDutt; Shindler, Kenneth S.

    2012-01-01

    Resveratrol is a naturally-occurring polyphenol that activates SIRT1, an NAD-dependent deacetylase. SRT501, a pharmaceutical formulation of resveratrol with enhanced systemic absorption, prevents neuronal loss without suppressing inflammation in mice with relapsing experimental autoimmune encephalomyelitis (EAE), a model of multiple sclerosis. In contrast, resveratrol has been reported to suppress inflammation in chronic EAE, although neuroprotective effects were not evaluated. The current st...

  9. Defective tryptophan catabolism underlies inflammation in mouse chronic granulomatous disease.

    Science.gov (United States)

    Romani, Luigina; Fallarino, Francesca; De Luca, Antonella; Montagnoli, Claudia; D'Angelo, Carmen; Zelante, Teresa; Vacca, Carmine; Bistoni, Francesco; Fioretti, Maria C; Grohmann, Ursula; Segal, Brahm H; Puccetti, Paolo

    2008-01-10

    Half a century ago, chronic granulomatous disease (CGD) was first described as a disease fatally affecting the ability of children to survive infections. Various milestone discoveries have since been made, from an insufficient ability of patients' leucocytes to kill microbes to the underlying genetic abnormalities. In this inherited disorder, phagocytes lack NADPH oxidase activity and do not generate reactive oxygen species, most notably superoxide anion, causing recurrent bacterial and fungal infections. Patients with CGD also suffer from chronic inflammatory conditions, most prominently granuloma formation in hollow viscera. The precise mechanisms of the increased microbial pathogenicity have been unclear, and more so the reasons for the exaggerated inflammatory response. Here we show that a superoxide-dependent step in tryptophan metabolism along the kynurenine pathway is blocked in CGD mice with lethal pulmonary aspergillosis, leading to unrestrained Vgamma1(+) gammadelta T-cell reactivity, dominant production of interleukin (IL)-17, defective regulatory T-cell activity and acute inflammatory lung injury. Although beneficial effects are induced by IL-17 neutralization or gammadelta T-cell contraction, complete cure and reversal of the hyperinflammatory phenotype are achieved by replacement therapy with a natural kynurenine distal to the blockade in the pathway. Effective therapy, which includes co-administration of recombinant interferon-gamma (IFN-gamma), restores production of downstream immunoactive metabolites and enables the emergence of regulatory Vgamma4(+) gammadelta and Foxp3(+) alphabeta T cells. Therefore, paradoxically, the lack of reactive oxygen species contributes to the hyperinflammatory phenotype associated with NADPH oxidase deficiencies, through a dysfunctional kynurenine pathway of tryptophan catabolism. Yet, this condition can be reverted by reactivating the pathway downstream of the superoxide-dependent step.

  10. Chronic citalopram administration causes a sustained suppression of serotonin synthesis in the mouse forebrain.

    Directory of Open Access Journals (Sweden)

    Gerard Honig

    Full Text Available BACKGROUND: Serotonin (5-HT is a neurotransmitter with important roles in the regulation of neurobehavioral processes, particularly those regulating affect in humans. Drugs that potentiate serotonergic neurotransmission by selectively inhibiting the reuptake of serotonin (SSRIs are widely used for the treatment of psychiatric disorders. Although the regulation of serotonin synthesis may be an factor in SSRI efficacy, the effect of chronic SSRI administration on 5-HT synthesis is not well understood. Here, we describe effects of chronic administration of the SSRI citalopram (CIT on 5-HT synthesis and content in the mouse forebrain. METHODOLOGY/PRINCIPAL FINDINGS: Citalopram was administered continuously to adult male C57BL/6J mice via osmotic minipump for 2 days, 14 days or 28 days. Plasma citalopram levels were found to be within the clinical range. 5-HT synthesis was assessed using the decarboxylase inhibition method. Citalopram administration caused a suppression of 5-HT synthesis at all time points. CIT treatment also caused a reduction in forebrain 5-HIAA content. Following chronic CIT treatment, forebrain 5-HT stores were more sensitive to the depleting effects of acute decarboxylase inhibition. CONCLUSIONS/SIGNIFICANCE: Taken together, these results demonstrate that chronic citalopram administration causes a sustained suppression of serotonin synthesis in the mouse forebrain. Furthermore, our results indicate that chronic 5-HT reuptake inhibition renders 5-HT brain stores more sensitive to alterations in serotonin synthesis. These results suggest that the regulation of 5-HT synthesis warrants consideration in efforts to develop novel antidepressant strategies.

  11. Novel mouse model of chronic Pseudomonas aeruginosa lung infection mimicking cystic fibrosis

    DEFF Research Database (Denmark)

    Hoffmann, Nadine; Rasmussen, Thomas Bovbjerg; Jensen, Peter Østrup;

    2005-01-01

    Pseudomonas aeruginosa causes a chronic infection in the lungs of cystic fibrosis (CF) patients by establishing an alginate-containing biofilm. The infection has been studied in several animal models; however, most of the models required artificial embedding of the bacteria. We present here a new...... pulmonary mouse model without artificial embedding. The model is based on a stable mucoid CF sputum isolate (NH57388A) with hyperproduction of alginate due to a deletion in mucA and functional N-acylhomoserine lactone (AHL)-based quorum-sensing systems. Chronic lung infection could be established in both CF...

  12. Chronic UVR Causes Increased Immunostaining of CD44 and Accumulation of Hyaluronan in Mouse Epidermis

    OpenAIRE

    Siiskonen, Hanna; Törrönen, Kari; Kumlin, Timo; Rilla, Kirsi; Tammi, Markku I; Tammi, Raija H.

    2011-01-01

    Chronic intense UV radiation is the main cause of epidermal tumors. Because hyaluronan (HA), a large extracellular polysaccharide, is known to promote malignant growth, hyaluronan expression was studied in a model in which long-term UV radiation (UVR) induces epidermal tumors. Mouse back skin was exposed three times a week for 10.5 months to UVR corresponding to one minimal erythema dose, processed for histology, and stained for hyaluronan and the hyaluronan receptor CD44. This exposure proto...

  13. Prevention impact of atorvastatin on rats'chronic hypoxic pulmonary hypertension%阿托伐他汀预防大鼠慢性低氧性肺动脉高压的观察

    Institute of Scientific and Technical Information of China (English)

    于凤霞; 杨海燕; 范民忠; 孔令亭

    2012-01-01

    目的 探讨阿托伐他汀对大鼠慢性低氧性肺动脉高压的干预作用.方法 采用慢性低氧性肺动脉高压大鼠模型.30只大鼠随机分为常氧组、低氧组和低氧阿托伐他汀干预组.4周后观察肺动脉压及右心肥厚指数,HE染色和电镜观察各组大鼠肺组织病理和超微结构变化.结果 低氧组大鼠平均肺动脉压力、右心肥厚指数高于正常组和阿托伐他汀干预组(P<0.05);光镜显示:4周后低氧组肺细小动脉血管壁平滑肌层明显增生,电镜下内皮细胞向管腔突起,胶原纤维增多,平滑肌细胞增生;而正常组、阿托伐他汀组大鼠肺组织血管壁的改变明显减轻.结论 阿托伐他汀可减轻低氧性肺细小动脉血管平滑肌的增生,减轻血管重构,降低慢性低氧性肺动脉高压大鼠肺动脉压力.%Objective To exporle the effect of atorvastatin on rats ' chronic hypoxic pulmonary hypertension. Method Adopting chronic hypoxic pulmonary hypertension rats modeL Total of 30 rats were randomly divided into 3 groups, they were normal group, hypoxic group and atorvastatin group. Four weeks after treatment, the mean of pulmonary artery pressure (mPAP) , right ventricle hypertrophy index of all rats were measured. Observation the lungs tissue pathological and ultra - structure changes by HE and electron microscope. Results The mean pulmonary artery pressure and right ventricle hypertrophy index of hypoxic group were higher than normal group (P <0. 05) and atrovastatin group (P <0. 05) . Light microscope showed that the smooth muscle layer of pulmonary arterioles vessel wall in hypoxic group were hyperplasia. Endotheliocyte was apophysis to lumens, collagen fibers was increase, smooth muscle cell was proliferation, vessel walls' change were light in normal group and arorvastatin group. Conclusions Atorvastatin could reduce the hypoxic pulmonary vascular smooth muscle hyperplasia, lighten vascular remodeling, lower pulmonary arterial

  14. The enduring hypoxic response of Mycobacterium tuberculosis.

    Directory of Open Access Journals (Sweden)

    Tige R Rustad

    Full Text Available BACKGROUND: A significant body of evidence accumulated over the last century suggests a link between hypoxic microenvironments within the infected host and the latent phase of tuberculosis. Studies to test this correlation have identified the M. tuberculosis initial hypoxic response, controlled by the two-component response regulator DosR. The initial hypoxic response is completely blocked in a dosR deletion mutant. METHODOLOGY/PRINCIPAL FINDINGS: We show here that a dosR deletion mutant enters bacteriostasis in response to in vitro hypoxia with only a relatively mild decrease in viability. In the murine infection model, the phenotype of the mutant was indistinguishable from that of the parent strain. These results suggested that additional genes may be essential for entry into and maintenance of bacteriostasis. Detailed microarray analysis of oxygen starved cultures revealed that DosR regulon induction is transient, with induction of nearly half the genes returning to baseline within 24 hours. In addition, a larger, sustained wave of gene expression follows the DosR-mediated initial hypoxic response. This Enduring Hypoxic Response (EHR consists of 230 genes significantly induced at four and seven days of hypoxia but not at initial time points. These genes include a surprising number of transcriptional regulators that could control the program of bacteriostasis. We found that the EHR is independent of the DosR-mediated initial hypoxic response, as EHR expression is virtually unaltered in the dosR mutant. CONCLUSIONS/SIGNIFICANCE: Our results suggest a reassessment of the role of DosR and the initial hypoxic response in MTB physiology. Instead of a primary role in survival of hypoxia induced bacteriostasis, DosR may regulate a response that is largely optional in vitro and in mouse infections. Analysis of the EHR should help elucidate the key regulatory factors and enzymatic machinery exploited by M. tuberculosis for long-term bacteriostasis in

  15. A New Mouse Model That Spontaneously Develops Chronic Liver Inflammation and Fibrosis.

    Directory of Open Access Journals (Sweden)

    Nina Fransén-Pettersson

    Full Text Available Here we characterize a new animal model that spontaneously develops chronic inflammation and fibrosis in multiple organs, the non-obese diabetic inflammation and fibrosis (N-IF mouse. In the liver, the N-IF mouse displays inflammation and fibrosis particularly evident around portal tracts and central veins and accompanied with evidence of abnormal intrahepatic bile ducts. The extensive cellular infiltration consists mainly of macrophages, granulocytes, particularly eosinophils, and mast cells. This inflammatory syndrome is mediated by a transgenic population of natural killer T cells (NKT induced in an immunodeficient NOD genetic background. The disease is transferrable to immunodeficient recipients, while polyclonal T cells from unaffected syngeneic donors can inhibit the disease phenotype. Because of the fibrotic component, early on-set, spontaneous nature and reproducibility, this novel mouse model provides a unique tool to gain further insight into the underlying mechanisms mediating transformation of chronic inflammation into fibrosis and to evaluate intervention protocols for treating conditions of fibrotic disorders.

  16. Mitochondrial dysfunction in the striatum of aged chronic mouse model of Parkinson's disease

    Directory of Open Access Journals (Sweden)

    Gaurav Patki

    2009-12-01

    Full Text Available Mitochondrial oxidative stress and dysfunction has been implicated as a possible mechanism for the onset and progression of Parkinson-like neurodegeneration. However, long-term mitochondrial defects in chronic animal neurodegenerative models have not been demonstrated. In this study, we investigated the function of striatal mitochondria 6 weeks after the induction of a chronic 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP mouse model of Parkinson’s disease (MPD. Although severe depression of mitochondrial respiration was observed immediately after acute administrations of MPTP, we failed to detect a significant mitochondrial inhibition in presence of striatal dopamine deficit 6 weeks after the chronic MPD induction in young adult mice. In contrast, when aged mice were chronically treated with MPTP and at 6 weeks post-treatment, these animals suffered an inhibition of the basal (state 4 and ADP-stimulated (state 3 respiration and a fall in ATP level in the striatal mitochondria. The aged chronic MPD also brought about a sustained diminution of striatal anti-oxidant enzyme levels including that of superoxide dismutases and cytochrome c. The mitochondrial deficits in the striatum of aged chronic MPD 6 weeks after treatment were further correlated with significant losses of striatal dopamine, tyrosine hydroxylase, dopamine uptake transporter, and with impaired movement when tested on a challenging beam. Our findings suggest that MPTP may trigger the neurodegenerative process by obstructing the mitochondrial function; however, striatal mitochondria in young animals may potentially rejuvenate, whereas mitochondrial dysfunction is sustained in the aged chronic MPD. Therefore, the aged chronic MPD may serve as a suitable investigative model for further elucidating the integral relationship between mitochondrial dysfunction and neurodegenerative disorder, and for assessing the therapeutic efficacy of mitochondrial protective agents as potential

  17. Neuroprotective effects and mechanisms of exercise in a chronic mouse model of Parkinson’s disease with moderate neurodegeneration

    OpenAIRE

    Lau, Yuen-Sum; Patki, Gaurav; Das-Panja, Kaberi; Le, Wei-dong; Ahmad, S. Omar

    2011-01-01

    The protective impact of exercise on neurodegenerative processes has not been confirmed, and the mechanisms underlying the benefit of exercise have not been determined in human Parkinson’s disease or in chronic animal disease models. This research examined the long-term neurological, behavioral, and mechanistic consequences of endurance exercise in experimental chronic parkinsonism. We used a chronic 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced mouse model of Parkinson’s disease with ...

  18. Effects of dietary creatine supplementation for 8 weeks on neuromuscular coordination and learning in male albino mouse following neonatal hypoxic ischemic insult.

    Science.gov (United States)

    Iqbal, Shahid; Ali, Muhammad; Akbar, Atif; Iqbal, Furhan

    2015-05-01

    Creatine monohydrate (Cr) is a dietary supplement known to improve cognitive functions and has positive therapeutic results under various clinical conditions. The aim of this study was to determine the effect of 2 % Cr supplementation on learning, memory formation, neuromuscular coordination, exploratory and locomotory in male albino mice following hypoxic ischemic insult. At postnatal day, 10 male albino mice pups were subjected to right common carotid artery ligation followed by 8 % hypoxia for 25 min. On postnatal day 20, male mice were separated from the litter and divided into two groups on the basis of special diet supplementation. One group was supplemented with 2 % Cr in diet while the other group was raised on ordinary rodent chow for 8 weeks. Behavioral observations were made during rota rod, open field and Morris water maze test for both treatments. It was observed that supplementation with 2 % Cr for 8 weeks following neonatal brain damage resulted in enhanced muscular strength, neuromuscular coordination and improved body weight. In Morris water maze test, it was observed that Cr supplementation significantly improved mean swimming speed and mice on 2 % Cr diet covered more distance but the spatial memory was not improved significantly following hypoxia ischemia encephalopathy (HIE). Open field parameters and percentage of infarct volume remained unaffected following Cr supplementation. We concluded that 2 % dietary Cr supplementation has a potential to improve the muscle strength and body weight in male albino mice following (HIE) and should be considered for the treatment of neurological ailments. PMID:25511980

  19. In vitro effects of piracetam on the radiosensitivity of hypoxic cells (adaptation of MTT assay to hypoxic conditions)

    International Nuclear Information System (INIS)

    This paper describes the adaptation of the MTT assay to hypoxic conditions in order to test the in vitro effect of piracetam on hypoxic cells and particularly on the radiosensitivity of hypoxic cells since this drug has shown clinical effect on acute and chronic hypoxia. The V79 cell line was selected by reference to preliminary hypoxic experiments using clonogenic assay and euoxic experiments using clonogenic and MTT assays. Cell growth and survival in our hypoxic conditions were assessed using MTT assay with an enclosure and special 48-well plates both made of glass. Growth curves on glass plates after 1-hour exposure to nitrogen versus air were comparable, so there is no bias effect due to gas composition. Survival curves using MTT versus reference clonogenic assay were comparable after radiation exposure in eu- and hypoxic conditions, and confirm the validity of our original technique for creating hypoxia. The Oxygen Enhancement Ratio was of about 3 for 1-hour hypoxic exposure. Piracetam gave no cytotoxic effect up to 10 mM of piracetam. Growth curves after continuous drug exposure and 1-hour euoxic versus hypoxic exposure gave no cytotoxic effect up to 10 mM of piracetam. Survival curves after continuous drug exposure to 10 mM of piracetam gave no significant effect on the radiosensitivity of hypoxic V79 cells using MTT or clonogenic assay. (author). 32 refs., 6 figs

  20. Interleukins in chronic liver disease: lessons learned from experimental mouse models

    Directory of Open Access Journals (Sweden)

    Hammerich L

    2014-09-01

    Full Text Available Linda Hammerich, Frank Tacke Department of Medicine III, University Hospital Aachen, Aachen, Germany Abstract: Interleukins represent a class of immunomodulatory cytokines, small intercellular signaling proteins, that are critically involved in the regulation of immune responses. They are produced in large amounts by various cell types during inflammatory reactions, and the balance of cytokines determines the outcome of an immune response. Therefore, cytokines are regarded as interesting therapeutic targets for the treatment of patients with liver diseases. Mouse models provide a good tool for in vivo studies on cytokine function, as human and mouse cytokines share many homologies. Sophisticated mouse models either mimicking distinct pathological conditions or targeting cytokines and cytokine-signaling pathways in the liver or even in distinct cellular compartments have provided enormous insight into the different functions of interleukins during hepatic inflammation. Interleukins may have pro- as well as anti-inflammatory functions in chronic liver diseases, some interleukins even both, dependent on the inflammatory stimulus, the producing and the responding cell type. IL-17, for example, promotes hepatic fibrogenesis through activation of hepatic stellate cells and facilitates development of liver cancer through recruitment of myeloid-derived suppressor cells. IL-22, on the other hand, protects from development of fibrosis or steatohepatitis. IL-12 balances T-helper (Th-1 and Th2 cell responses in infectious disease models. IL-13 and IL-33, two cytokines related to Th2 cells and innate lymphoid cells, promote fibrotic responses in the liver. IL-10 is the prototypic anti-inflammatory interleukin with tissue-protective functions during chronic liver injury and fibrogenesis. Despite its critical role for inducing the acute-phase response in the liver, IL-6 signaling is protective during fibrosis progression, but promotes hepatocellular carcinoma

  1. 46. Micronuclei induced by chronical treatment of SO2 inhalation in mouse bone marrow cells

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    In the chronical experiment of treating with sulfur dioxide(SO2) inhalation, Micronuclei(MN) frequencies in the polychromatophilic erythroblasts(PCE) of mouse bone marrow and the frequencies of cells with MN were significantly increased in dose-dependent manner. There is a significant difference between the male and the female animals. The results also showed that SO2 inhibited urethone-induced MN formation, it is a antagonistic joint action to Urethone. These results furtherly confirm that SO2 inhalation is a clastogenetic and genotoxic agent to mammalian cells, and the combination roles of SO2 and other mutagens are complexity.

  2. Chronic administration of citalopram inhibited El mouse convulsions and decreased monoamine oxidase-A activity.

    OpenAIRE

    Kabuto, Hideaki; Yokoi, Isao; Endo, Atsushi; Takei, Mineo; Kurimoto, Tadashi; Mori, Akitane

    1994-01-01

    Serotonin (5-HT) is thought to play an important role in the seizures of El mice because the seizure threshold of El mice correlates with the 5-HT concentration in the central nervous system. In this study, the anticonvulsant effect of a 5-HT reuptake blocker, citalopram, was evaluated behaviorally and biochemically. El mouse convulsions were inhibited by chronic administration of citalopram (80 mg/kg/day, p.o. for 2 weeks), but were not inhibited by acute administration of citalopram (80 mg/...

  3. Hormetic Effect of Chronic Hypergravity in a Mouse Model of Allergic Asthma and Rhinitis

    OpenAIRE

    Tae Young Jang; Ah-Yeoun Jung; Young Hyo Kim

    2016-01-01

    We aimed to evaluate the effect of chronic hypergravity in a mouse model of allergic asthma and rhinitis. Forty BALB/c mice were divided as: group A (n = 10, control) sensitized and challenged with saline, group B (n = 10, asthma) challenged by intraperitoneal and intranasal ovalbumin (OVA) to induce allergic asthma and rhinitis, and groups C (n = 10, asthma/rotatory control) and D (n = 10, asthma/hypergravity) exposed to 4 weeks of rotation with normogravity (1G) or hypergravity (5G) during ...

  4. PPARα Protein Expression Was Increased by Four Weeks of Intermittent Hypoxic Training via AMPKα2-Dependent Manner in Mouse Skeletal Muscle.

    Directory of Open Access Journals (Sweden)

    Ge Li

    Full Text Available Peroxisome proliferator-activated receptor α (PPARα is critical for muscle endurance due to its role in the regulation of fatty acid oxidation. The 5'-AMP-activated protein kinase (AMPK is an energy sensor in cells, but its role in PPARα regulation in vivo remains unknown. In this study, we examined PPARα expression in the skeletal muscle of AMPKα2 overexpression (OE, knockout (KO and wild-type (WT mice after four weeks of exercise under intermittent hypoxia. WT, OE and KO mice were used at 40 mice/strain and randomly subdivided into four subgroups: control (C, running (R, hypoxia (H, and running plus hypoxia (R+H at 10 mice/group. The treadmill running was performed at the speed of 12 m/min, 60 min/day with a slope of 0 degree for four weeks. The hypoxia treatment was performed in daytime with normobaric hypoxia (11.20% oxygen, 8 hours/day. In the R+H group, the treadmill running was conducted in the hypoxic condition. AMPKα2, phosphor-AMPKα (p-AMPKα (Thr172, nuclear PPARα proteins were measured by Western blot and the medium chain acyl coenzyme A dehydrogenase (MCAD mRNA, the key enzyme for fatty acid oxidation and one of the PPARα target genes, was also measured in skeletal muscles after the interventions. The results showed that nuclear PPARα protein was significantly increased by R+H in WT muscles, the increase was enhanced by 41% (p<0.01 in OE mice, but was reduced by 33% (p<0.01 in KO mice. The MCAD mRNA expression was increased after four weeks of R+H intervention. The change in MCAD mRNA followed a similar trend as that of PPARα protein in OE and KO mice. Our data suggest that the increase in nuclear PPARα protein by four-week exercise training under the intermittent hypoxia was dependent on AMPK activation.

  5. Chronic morphine induces premature mitosis of proliferating cells in the adult mouse subgranular zone.

    Science.gov (United States)

    Mandyam, Chitra D; Norris, Rebekah D; Eisch, Amelia J

    2004-06-15

    The birth of cells with neurogenic potential in the adult brain is assessed commonly by detection of exogenous S phase markers, such as bromodeoxyuridine (BrdU). Analysis of other phases of the cell cycle, however, can provide insight into how external factors, such as opiates, influence the cycling of newly born cells. To this end, we examined the expression of two endogenous cell cycle markers in relation to BrdU: proliferating cell nuclear antigen (PCNA) and phosphorylated histone H3 (pHisH3). Two hours after one intraperitoneal BrdU injection, BrdU-, PCNA-, and pHisH3-immunoreactive (IR) cells exhibited similar distribution in the adult mouse subgranular zone (SGZ). Quantitative analysis within the SGZ revealed a relative abundance of cells labeled for PCNA > BrdU > pHisH3. Similar to our reports in rat SGZ, chronic morphine treatment decreased BrdU- and PCNA-IR cells in mouse SGZ by 28 and 38%, respectively. We also show that pHisH3-IR cells are influenced by chronic morphine to a greater extent (58% decrease) than are BrdU- or PCNA-IR cells. Cell cycle phase analysis of SGZ BrdU-IR cells using triple labeling for BrdU, PCNA, and pHisH3 revealed premature mitosis in chronic morphine-treated mice. These results suggest that morphine-treated mice have a shorter Gap2/mitosis (G(2)/M) phase when compared to sham-treated mice. These findings demonstrate the power of using a combination of exogenous and endogenous cell cycle markers and nuclear morphology to track proliferating cells through different phases of the cell cycle and to reveal the regulation of cell cycle phase by chronic morphine. PMID:15160390

  6. Transcriptomic responses in mouse brain exposed to chronic excess of the neurotransmitter glutamate

    Directory of Open Access Journals (Sweden)

    Pal Ranu

    2010-06-01

    Full Text Available Abstract Background Increases during aging in extracellular levels of glutamate (Glu, the major excitatory neurotransmitter in the brain, may be linked to chronic neurodegenerative diseases. Little is known about the molecular responses of neurons to chronic, moderate increases in Glu levels. Genome-wide gene expression in brain hippocampus was examined in a unique transgenic (Tg mouse model that exhibits moderate Glu hyperactivity throughout the lifespan, the neuronal Glutamate dehydrogenase (Glud1 mouse, and littermate 9 month-old wild type mice. Results Integrated bioinformatic analyses on transcriptomic data were used to identify bio-functions, pathways and gene networks underlying neuronal responses to increased Glu synaptic release. Bio-functions and pathways up-regulated in Tg mice were those associated with oxidative stress, cell injury, inflammation, nervous system development, neuronal growth, and synaptic transmission. Increased gene expression in these functions and pathways indicated apparent compensatory responses offering protection against stress, promoting growth of neuronal processes (neurites and re-establishment of synapses. The transcription of a key gene in the neurite growth network, the kinase Ptk2b, was significantly up-regulated in Tg mice as was the activated (phosphorylated form of the protein. In addition to genes related to neurite growth and synaptic development, those associated with neuronal vesicle trafficking in the Huntington's disease signalling pathway, were also up-regulated. Conclusions This is the first study attempting to define neuronal gene expression patterns in response to chronic, endogenous Glu hyperactivity at brain synapses. The patterns observed were characterized by a combination of responses to stress and stimulation of nerve growth, intracellular transport and recovery.

  7. Renal Impairment with Sublethal Tubular Cell Injury in a Chronic Liver Disease Mouse Model.

    Directory of Open Access Journals (Sweden)

    Tokiko Ishida

    Full Text Available The pathogenesis of renal impairment in chronic liver diseases (CLDs has been primarily studied in the advanced stages of hepatic injury. Meanwhile, the pathology of renal impairment in the early phase of CLDs is poorly understood, and animal models to elucidate its mechanisms are needed. Thus, we investigated whether an existing mouse model of CLD induced by 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC shows renal impairment in the early phase. Renal injury markers, renal histology (including immunohistochemistry for tubular injury markers and transmission electron microscopy, autophagy, and oxidative stress were studied longitudinally in DDC- and standard diet-fed BALB/c mice. Slight but significant renal dysfunction was evident in DDC-fed mice from the early phase. Meanwhile, histological examinations of the kidneys with routine light microscopy did not show definitive morphological findings, and electron microscopic analyses were required to detect limited injuries such as loss of brush border microvilli and mitochondrial deformities. Limited injuries have been recently designated as sublethal tubular cell injury. As humans with renal impairment, either with or without CLD, often show almost normal tubules, sublethal injury has been of particular interest. In this study, the injuries were associated with mitochondrial aberrations and oxidative stress, a possible mechanism for sublethal injury. Intriguingly, two defense mechanisms were associated with this injury that prevent it from progressing to apparent cell death: autophagy and single-cell extrusion with regeneration. Furthermore, the renal impairment of this model progressed to chronic kidney disease with interstitial fibrosis after long-term DDC feeding. These findings indicated that DDC induces renal impairment with sublethal tubular cell injury from the early phase, leading to chronic kidney disease. Importantly, this CLD mouse model could be useful for studying the

  8. 硫化氢对慢性低氧高二氧化碳模型大鼠学习记忆的影响%Hydrogen Sulfide on Rats' Learning Memory Deficit by Induced Chronic Hypoxic Hypercapnia

    Institute of Scientific and Technical Information of China (English)

    刘银花; 杨汉文; 王小同; 金露; 程英; 祝家群

    2011-01-01

    Aim: To explore the effect of hydrogen sulfide on learning memory deficit in rats induced by chronic hypoxic hypercapnia. Methods: Twenty-four male Sprague-Dawley rats selected by Morris water maze were randomly divided into three groups (8 in each group) : normal control (NC) group,hypoxic hypercapnia + saline solution (HHSS) group, hypoxic hypercapnia + sodium hydrosulfide (HHSH) group. The rats were received the intraperitoneal injecion with sodium hydrosulfide in the HHSH group and saline solution in the HHSS group. At the end of 4th week, all rats were tested by Morris water maze. Then the mPAP was measured by external jugularvein cannula the ratio of the right ventricle (RV) to the left ventricle+septum (LV+S) was calculated, and the hydrogen sulfide concentration in the plasma was measured. Results : ①Compared with the NC group, the value of mPAP and RV/(LV+S) in the HHSS group was higher (p<0. 05) , the level of hydrogen sulfide in the plasma was lower (p<0. 05) , the escape latency to find the platform and swirrming travel distance were longer, times of crossing the plantform were much reduced (p<0. 05) . ②Compared with the HHSS group, the value of mPAP and RV/(LV+S) in the HHSH group was lower (p<0. 05), the level of hydrogen sulfide in the plasma was higher (p<0. 05) , the escape latency and swimming travel distance were reduced (P <0. 05) . Conclusion: Ratslearning and memory deficit exposed to chronic hypoxic hypercapina may be ameliorated by hydrogen sulfide supplementation.%目的:探讨硫化氢对慢性低O2高CO2 模型大鼠学习记忆的影响.方法:经Morris水迷宫训练淘汰后的24只SD大鼠随机分为3组:正常对照(NC)组,低O2高CO 2+生理盐水(HHSS)组,低O2高CO2 +硫氢化钠(HHSH)组.HHSH组和HHSS组每天置常压低O 2高CO2舱内8 h,每周6d,共4周观察,4周后Morris水迷宫检查空间学习记忆变化,测定大鼠肺动脉平均压(mPAP)和右心室壁(RV)/左心室加室间隔(LV+S)比值、血浆

  9. Chronic brief restraint decreases in vivo binding of benzodiazepine receptor ligand to mouse brain.

    Science.gov (United States)

    Mosaddeghi, M; Burke, T F; Moerschbaecher, J M

    1993-01-01

    This study examines the effects of chronic brief restraint on in vivo benzodiazepine (BZD) receptor binding in mouse brain. Three groups of mice were used. Mice in group 1 were neither restrained nor injected (ACUTE control). Mice in group 2 were restrained for 5-6 s by grabbing the back skin and holding the subject upside-down at a 45 degrees angle as if to be injected (CHRONIC SHAM control) for 7 d. Mice in group 3 (CHRONIC SALINE) received daily single intraperitoneal (ip) injections of saline (5 mL/kg) for 7 d. On d 8 BZD receptors were labeled in vivo by administration of 3 microCi [3H]flumazenil (ip). The levels of ligand bound in vivo to cerebral cortex (CX), cerebellum (CB), brain stem (BS), striatum (ST), hippocampus (HP), and hypothalamus (HY) were determined. Results indicated that the level of binding was significantly (p stress produces a decrease in BZD receptor binding sites. PMID:8385464

  10. CFTR and sphingolipids mediate hypoxic pulmonary vasoconstriction

    OpenAIRE

    Tabeling, Christoph; Yu, Hanpo; Wang, Liming; Ranke, Hannes; Goldenberg, Neil M.; Zabini, Diana; Noe, Elena; Krauszman, Adrienn; Gutbier, Birgitt; Yin, Jun; Schaefer, Michael,; Arenz, Christoph; Hocke, Andreas C.; Suttorp, Norbert; Proia, Richard L.

    2015-01-01

    Hypoxic pulmonary vasoconstriction (HPV) is a physiological mechanism that protects against systemic hypoxemia by redistributing blood flow from poorly to better ventilated areas of the lung, thereby minimizing ventilation-perfusion mismatch. However, in chronic hypoxemia-associated lung disease, HPV contributes to pulmonary hypertension. In this study, we provide novel evidence for a dual role of sphingolipids as important signal mediators in HPV, which critically depends on the presence of ...

  11. An optimised mouse model of chronic pancreatitis with a combination of ethanol and cerulein

    Science.gov (United States)

    Ahmadi, Abbas; Nikkhoo, Bahram; Mokarizadeh, Aram; Rahmani, Mohammad-Reza; Fakhari, Shohreh; Mohammadi, Mehdi

    2016-01-01

    Introduction Chronic pancreatitis (CP) is an intractable and multi-factorial disorder. Developing appropriate animal models is an essential step in pancreatitis research, and the best ones are those which mimic the human disorder both aetiologically and pathophysiologically. The current study presents an optimised protocol for creating a murine model of CP, which mimics the initial steps of chronic pancreatitis in alcohol chronic pancreatitis and compares it with two other mouse models treated with cerulein or ethanol alone. Material and methods Thirty-two male C57BL/6 mice were randomly selected, divided into four groups, and treated intraperitoneally with saline (10 ml/kg, control group), ethanol (3 g/kg; 30% v/v), cerulein (50 µg/kg), or ethanol + cerulein, for six weeks. Histopathological and immunohistochemical assays for chronic pancreatitis index along with real-time PCR assessments for mRNA levels of inflammatory cytokines and fibrogenic markers were conducted to verify the CP induction. Results The results indicated that CP index (CPI) was significantly increased in ethanol-cerulein mice compared to the saline, ethanol, and cerulein groups (p < 0.001). Interleukin 1β (IL-1β), tumor necrosis factor α (TNF-α), transforming growth factor β (TGF-β), α-smooth muscle actin (α-SMA), and myeloperoxidase activity were also significantly greater in both cerulein and ethanol-cerulein groups than in the saline treated animals (p < 0.001). Immunohistochemical analysis revealed enhanced expression of TGF-β and α-SMA in ethanol-cerulein mice compared to the saline group. Conclusions Intraperitoneal (IP) injections of ethanol and cerulein could successfully induce CP in mice. IP injections of ethanol provide higher reproducibility compared to ethanol feeding. The model is simple, non-invasive, reproducible, and time-saving. Since the protocol mimics the initial phases of CP development in alcoholics, it can be used for investigating basic mechanisms and testing

  12. New Mouse Models to Investigate the Efficacy of Drug Combinations in Human Chronic Myeloid Leukemia.

    Science.gov (United States)

    Lin, Hanyang; Woolfson, Adrian; Jiang, Xiaoyan

    2016-01-01

    Chronic myeloid leukemia (CML) comprises a simple and effective paradigm for generating new insights into the cellular origin, pathogenesis, and treatment of many types of human cancer. In particular, mouse models of CML have greatly facilitated the understanding of the underlying molecular mechanisms and pathogenesis of this disease and have led to the identification of new drug targets that in some cases offer the possibility of functional cure. There are currently three established CML mouse models: the BCR-ABL transgenic model, the BCR-ABL retroviral transduction/transplantation model, and the xenotransplant immunodeficient model. Each has its own unique advantages and disadvantages. Depending on the question of interest, some models may be more appropriate than others. In this chapter, we describe a newly developed xenotransplant mouse model to determine the efficacy of novel therapeutic agents, either alone or in combination. The model facilitates the evaluation of the frequency of leukemic stem cells with long-term leukemia-initiating activity, a critical subcellular population that causes disease relapse and progression, through the utilization of primary CD34(+) CML stem/progenitor cells obtained from CML patients at diagnosis and prior to drug treatment. We have also investigated the effectiveness of new combination treatment strategies designed to prevent the development of leukemia in vivo using BCR-ABL (+) blast crisis cells as a model system. These types of in vivo studies are important for the prediction of individual patient responses to drug therapy, and have the potential to facilitate the design of personalized combination therapy strategies. PMID:27581149

  13. Hormetic Effect of Chronic Hypergravity in a Mouse Model of Allergic Asthma and Rhinitis

    Science.gov (United States)

    Jang, Tae Young; Jung, Ah-Yeoun; Kim, Young Hyo

    2016-06-01

    We aimed to evaluate the effect of chronic hypergravity in a mouse model of allergic asthma and rhinitis. Forty BALB/c mice were divided as: group A (n = 10, control) sensitized and challenged with saline, group B (n = 10, asthma) challenged by intraperitoneal and intranasal ovalbumin (OVA) to induce allergic asthma and rhinitis, and groups C (n = 10, asthma/rotatory control) and D (n = 10, asthma/hypergravity) exposed to 4 weeks of rotation with normogravity (1G) or hypergravity (5G) during induction of asthma/rhinitis. Group D showed significantly decreased eosinophils, neutrophils, and lymphocytes in their BAL fluid compared with groups B and C (p polymerase chain reaction using lung homogenate, the expression of IL-1β was significantly upregulated (p < 0.001) and IL-4 and IL-10 significantly downregulated (p < 0.05) in group D. Infiltration of inflammatory cells into lung parenchyma and turbinate, and the thickness of respiratory epithelium was significantly reduced in group D (p < 0.05). The expression of Bcl-2 and heme oxygenase-1 were significantly downregulated, Bax and extracellular dismutase significantly upregulated in Group D. Therefore, chronic hypergravity could have a hormetic effect for allergic asthma and rhinitis via regulation of genes involved in antioxidative and proapoptotic pathways. It is possible that we could use hypergravity machinery for treating allergic respiratory disorders.

  14. Selenoether oxytocin analogues have analgesic properties in a mouse model of chronic abdominal pain.

    Science.gov (United States)

    de Araujo, Aline Dantas; Mobli, Mehdi; Castro, Joel; Harrington, Andrea M; Vetter, Irina; Dekan, Zoltan; Muttenthaler, Markus; Wan, JingJing; Lewis, Richard J; King, Glenn F; Brierley, Stuart M; Alewood, Paul F

    2014-01-01

    Poor oral availability and susceptibility to reduction and protease degradation is a major hurdle in peptide drug development. However, drugable receptors in the gut present an attractive niche for peptide therapeutics. Here we demonstrate, in a mouse model of chronic abdominal pain, that oxytocin receptors are significantly upregulated in nociceptors innervating the colon. Correspondingly, we develop chemical strategies to engineer non-reducible and therefore more stable oxytocin analogues. Chemoselective selenide macrocyclization yields stabilized analogues equipotent to native oxytocin. Ultra-high-field nuclear magnetic resonance structural analysis of native oxytocin and the seleno-oxytocin derivatives reveals that oxytocin has a pre-organized structure in solution, in marked contrast to earlier X-ray crystallography studies. Finally, we show that these seleno-oxytocin analogues potently inhibit colonic nociceptors both in vitro and in vivo in mice with chronic visceral hypersensitivity. Our findings have potentially important implications for clinical use of oxytocin analogues and disulphide-rich peptides in general. PMID:24476666

  15. Transient and persistent metabolomic changes in plasma following chronic cigarette smoke exposure in a mouse model.

    Directory of Open Access Journals (Sweden)

    Charmion I Cruickshank-Quinn

    Full Text Available Cigarette smoke exposure is linked to the development of a variety of chronic lung and systemic diseases in susceptible individuals. Metabolomics approaches may aid in defining disease phenotypes, may help predict responses to treatment, and could identify biomarkers of risk for developing disease. Using a mouse model of chronic cigarette smoke exposure sufficient to cause mild emphysema, we investigated whether cigarette smoke induces distinct metabolic profiles and determined their persistence following smoking cessation. Metabolites were extracted from plasma and fractionated based on chemical class using liquid-liquid and solid-phase extraction prior to performing liquid chromatography mass spectrometry-based metabolomics. Metabolites were evaluated for statistically significant differences among group means (p-value≤0.05 and fold change ≥1.5. Cigarette smoke exposure was associated with significant differences in amino acid, purine, lipid, fatty acid, and steroid metabolite levels compared to air exposed animals. Whereas 60% of the metabolite changes were reversible, 40% of metabolites remained persistently altered even following 2 months of smoking cessation, including nicotine metabolites. Validation of metabolite species and translation of these findings to human plasma metabolite signatures induced by cigarette smoking may lead to the discovery of biomarkers or pathogenic pathways of smoking-induced disease.

  16. Prostatic inflammation induces fibrosis in a mouse model of chronic bacterial infection.

    Directory of Open Access Journals (Sweden)

    Letitia Wong

    Full Text Available Inflammation of the prostate is strongly correlated with development of lower urinary tract symptoms and several studies have implicated prostatic fibrosis in the pathogenesis of bladder outlet obstruction. It has been postulated that inflammation induces prostatic fibrosis but this relationship has never been tested. Here, we characterized the fibrotic response to inflammation in a mouse model of chronic bacterial-induced prostatic inflammation. Transurethral instillation of the uropathogenic E. coli into C3H/HeOuJ male mice induced persistent prostatic inflammation followed by a significant increase in collagen deposition and hydroxyproline content. This fibrotic response to inflammation was accompanied with an increase in collagen synthesis determined by the incorporation of 3H-hydroxyproline and mRNA expression of several collagen remodeling-associated genes, including Col1a1, Col1a2, Col3a1, Mmp2, Mmp9, and Lox. Correlation analysis revealed a positive correlation of inflammation severity with collagen deposition and immunohistochemical staining revealed that CD45+VIM+ fibrocytes were abundant in inflamed prostates at the time point coinciding with increased collagen synthesis. Furthermore, flow cytometric analysis demonstrated an increased percentage of these CD45+VIM+ fibrocytes among collagen type I expressing cells. These data show-for the first time-that chronic prostatic inflammation induces collagen deposition and implicates fibrocytes in the fibrotic process.

  17. Effect of chronic intermittent hypoxia on theophylline metabolism in mouse liver

    Institute of Scientific and Technical Information of China (English)

    CHEN Xiao-yang; ZENG Yi-ming; ZHANG Yi-xiang; WANG Wan-yu; WU Run-hua

    2013-01-01

    Background Chronic intermittent hypoxia (CIH) has been associated with abnormalities in the liver,which is the most important organ for drug metabolism.This study aimed to investigate the effect of CIH on theophylline metabolism in mouse liver.Methods Eight C57BL/6J mice were exposed to CIH for 12 weeks.Eight C57BL/6J mice were exposed to room air as a control group.Serum levels of alanine aminotransferase and aspartate aminotransferase were measured.Liver histology was observed by light and electron microscopy.Total hepatic cytochrome P450 concentration was measured.Hepatocytes were isolated and incubated with 15 mg/ml theophylline for four hours.After incubation,the theophylline concentration in the supernatant was measured and the theophylline metabolism rate was calculated.Results CIH did not affect the serum transaminase levels.Livers from mice exposed to CIH showed hepatocellular edema,and liver cells had fuzzy rough endoplasmic reticulum under the electron microscope.The theophylline metabolism rate was significantly inhibited by CIH compared with controls; (16.60±2.43)% vs.(21.58±4.52)% (P=0.02).The total liver cytochrome P450 concentration in the CIH group was significantly lower than in the control group;(0.83±0.08) vs.(1.13±0.21) mol/mg microsomal protein (P=0.004).Conclusion CIH decreases theophylline metabolism by mouse hepatocytes,which may correlate with the downregulation of cytochrome P450 expression by CIH.

  18. Chronic cellular imaging of mouse visual cortex during operant behavior and passive viewing

    Directory of Open Access Journals (Sweden)

    Mark L Andermann

    2010-03-01

    Full Text Available Nearby neurons in mammalian neocortex demonstrate a great diversity of cell types and connectivity patterns. The importance of this diversity for computation is not understood. While extracellular recording studies in visual cortex have provided a particularly rich description of behavioral modulation of neural activity, new methods are needed to dissect the contribution of specific circuit elements in guiding visual perception. Here, we describe a method for three-dimensional cellular imaging of neural activity in the awake mouse visual cortex during active discrimination and passive viewing of visual stimuli. Head-fixed mice demonstrated robust discrimination for many hundred trials per day after initial task acquisition. To record from multiple neurons during operant behavior with single-trial resolution and minimal artifacts, we built a sensitive microscope for two-photon calcium imaging, capable of rapid tracking of neurons in three dimensions. We demonstrate stable recordings of cellular calcium activity during discrimination behavior across hours, days, and weeks, using both synthetic and genetically-encoded calcium indicators. When combined with molecular and genetic technologies in mice (e.g., cell-type specific transgenic labeling, this approach allows the identification of neuronal classes in vivo. Physiological measurements from distinct classes of neighboring neurons will enrich our understanding of the coordinated roles of diverse elements of cortical microcircuits in guiding sensory perception and perceptual learning. Further, our method provides a high-throughput, chronic in vivo assay of behavioral influences on cellular activity that is applicable to a wide range of mouse models of neurologic disease.

  19. A low protein diet increases the hypoxic tolerance in Drosophila.

    Directory of Open Access Journals (Sweden)

    Paul Vigne

    Full Text Available Dietary restriction is well known to increase the life span of a variety of organisms from yeast to mammals, but the relationships between nutrition and the hypoxic tolerance have not yet been considered. Hypoxia is a major cause of cell death in myocardial infarction and stroke. Here we forced hypoxia-related death by exposing one-day-old male Drosophila to chronic hypoxia (5% O(2 and analysed their survival. Chronic hypoxia reduced the average life span from 33.6 days to 6.3 days when flies were fed on a rich diet. A demographic analysis indicated that chronic hypoxia increased the slope of the mortality trajectory and not the short-term risk of death. Dietary restriction produced by food dilution, by yeast restriction, or by amino acid restriction partially reversed the deleterious action of hypoxia. It increased the life span of hypoxic flies up to seven days, which represented about 25% of the life time of an hypoxic fly. Maximum survival of hypoxic flies required only dietary sucrose, and it was insensitive to drugs such as rapamycin and resveratrol, which increase longevity of normoxic animals. The results thus uncover a new link between protein nutrition, nutrient signalling, and resistance to hypoxic stresses.

  20. Complement protein C3 exacerbates prion disease in a mouse model of chronic wasting disease.

    Science.gov (United States)

    Michel, Brady; Ferguson, Adam; Johnson, Theodore; Bender, Heather; Meyerett-Reid, Crystal; Wyckoff, A Christy; Pulford, Bruce; Telling, Glenn C; Zabel, Mark D

    2013-12-01

    Accumulating evidence shows a critical role of the complement system in facilitating attachment of prions to both B cells and follicular dendritic cells and assisting in prion replication. Complement activation intensifies disease in prion-infected animals, and elimination of complement components inhibits prion accumulation, replication and pathogenesis. Chronic wasting disease (CWD) is a highly infectious prion disease of captive and free-ranging cervid populations that utilizes the complement system for efficient peripheral prion replication and most likely efficient horizontal transmission. Here we show that complete genetic or transient pharmacological depletion of C3 prolongs incubation times and significantly delays splenic accumulation in a CWD transgenic mouse model. Using a semi-quantitative prion amplification scoring system we show that C3 impacts disease progression in the early stages of disease by slowing the rate of prion accumulation and/or replication. The delayed kinetics in prion replication correlate with delayed disease kinetics in mice deficient in C3. Taken together, these data support a critical role of C3 in peripheral CWD prion pathogenesis. PMID:24038599

  1. Erythropoietin-mediated neuroprotection in a pediatric mouse model of chronic hypoxia.

    Science.gov (United States)

    Chung, Eugene; Kong, Xiangmei; Goldberg, Mark P; Stowe, Ann M; Raman, Lakshmi

    2015-06-15

    Chronic hypoxia (CH), a disease state that accounts for significant morbidity and mortality in pediatrics, occurs in many children during critical periods of hippocampal development and cortical myelination. Hippocampal neurogenesis occurs throughout postnatal life and is important for normal development, thus impairment results in long-term cognitive deficits. Erythropoietin (EPO), a drug commonly known for its role in erythrogenesis, has recently been evaluated in neuroprotection in neonatal injury models and preterm brain injury. However, the effects of EPO therapy on hippocampal neurogenesis and myelination in pediatric CH are unknown. We show that CH decreases hippocampal neurogenesis in a pediatric mouse model. This decrease in early and late progenitors, and actively dividing cells is rescued with EPO treatment. Furthermore, we show that CH during this critical time decreases oligodendrocyte progenitor (OPC) populations in the cortex, leading to defective myelination. However, EPO therapy is only able to rescue the OPC but not the loss of mature myelin. Overall, our findings demonstrate that CH in developing mice has significant effects on hippocampal neurogenesis and OPCs, which can be rescued with EPO treatment. Future studies should confirm the role of this FDA-approved therapy in neuroprotection in at-risk pediatric populations. PMID:25899777

  2. Restorative effect of endurance exercise on behavioral deficits in the chronic mouse model of Parkinson's disease with severe neurodegeneration

    OpenAIRE

    Lau Yuen-Sum; Kurz Max J; Pothakos Konstantinos

    2009-01-01

    Abstract Background Animal models of Parkinson's disease have been widely used for investigating the mechanisms of neurodegenerative process and for discovering alternative strategies for treating the disease. Following 10 injections with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP, 25 mg/kg) and probenecid (250 mg/kg) over 5 weeks in mice, we have established and characterized a chronic mouse model of Parkinson's disease (MPD), which displays severe long-term neurological and patholog...

  3. Hypoxic radiosensitization: adored and ignored

    DEFF Research Database (Denmark)

    Overgaard, Jens

    2007-01-01

    resistance can be eliminated or modified by normobaric or hyperbaric oxygen or by the use of nitroimidazoles as hypoxic radiation sensitizers. More recently, attention has been given to hypoxic cytotoxins, a group of drugs that selectively or preferably destroys cells in a hypoxic environment. An updated.......71 to 0.86) for the outcome of locoregional control and with an associated significant overall survival benefit (odds ratio = 0.87; 95% CI, 0.80 to 0.95). No significant influence was found on the incidence of distant metastases or on the risk of radiation-related complications. Ample data exist to...... support a high level of evidence for the benefit of hypoxic modification. However, hypoxic modification still has no impact on general clinical practice. Udgivelsesdato: 2007-Sep-10...

  4. Chronic unpredictable stress decreases expression of brain-derived neurotrophic factor (BDNF in mouse ovaries: relationship to oocytes developmental potential.

    Directory of Open Access Journals (Sweden)

    Li-Min Wu

    Full Text Available BACKGROUND: Brain-derived neurotropic factor (BDNF was originally described in the nervous system but has been shown to be expressed in ovary tissues recently, acting as a paracrine/autocrine regulator required for developments of follicles and oocytes. Although it is generally accepted that chronic stress impairs female reproduction and decreases the expression of BDNF in limbic structures of central nervous system, which contributes to mood disorder. However, it is not known whether chronic stress affects oocytes developments, nor whether it affects expression of BDNF in ovary. METHODS: Mice were randomly assigned into control group, stressed group, BDNF-treated group and BDNF-treated stressed group. The chronic unpredictable mild stress model was used to produce psychosocial stress in mice, and the model was verified by open field test and hypothalamic-pituitary-adrenal (HPA axis activity. The methods of immunohistochemistry and western blotting were used to detect BDNF protein level and distribution. The number of retrieved oocytes, oocyte maturation, embryo cleavage and the rates of blastocyst formation after parthenogenetic activation were evaluated. RESULTS: Chronic unpredictable stress decreased the BDNF expression in antral follicles, but didn't affect the BDNF expression in primordial, primary and secondary follicles. Chronic unpredictable stress also decreased the number of retrieved oocytes and the rate of blastocyst formation, which was rescued by exogenous BDNF treatment. CONCLUSION: BDNF in mouse ovaries may be related to the decreased number of retrieved oocytes and impaired oocytes developmental potential induced by chronic unpredictable stress.

  5. The Role of Endogenous Carbon Monoxide in the Hypoxic Vascular Remodeling of Rat Model of Hypoxic Pulmonary Hypertension

    Institute of Scientific and Technical Information of China (English)

    甄国华; 张珍祥; 徐永健

    2003-01-01

    We investigated the expression of heme oxygenase-1 (HO-l) gene and production of endogenous carbon monoxide (CO) in the rat lung tissue at different time points of chronic hypoxic pulmonary hypertension and the effect of hemin on the expression of HO-1 gene and pulmonary hypertension. A rat model of hypoxic pulmonary hypertension was recreated by exposure to intermittent normobaric hypoxic environment (10 % O2 ). Reverse transcriptase polymerase chain reaction (RT-PCR) was performed to determine the level of HO-1 mRNA in the rat lung tissue and double wave length spectrophotometry was used to evaluate the quantity of COHb in arterial blood. Cardiac catheterization was employed to measure the right ventricular systolic pressure (RVSP) and HE staining was performed in dissected lung tissue to observe the pathological changes of the intra-acinar pulmonary arteries (IAPA). It was found that (1) There was a low level of HO-1 mRNA in normal rat lung tissue, but the level of HO-1 mRNA increased by 2-4 times in the lung tissue of hypoxic rats (P<0.01). The quantity of COHb was 2-3 times those of control group (P<0.01or P<0. 05). These were accompanied by the increased of RVSP and the thickened IAPA; (2) Hemin could keep the HO-1 mRNA and COHb in the hypoxic rat lung tissue at a high level, and partially suppressed the increase of rat RVSP, thereby ameliorating the pathological changes of IAPA.In conclusion, the upregulation of the expression of HO-1 gene and production of CO in the rat lung of hypoxic pulmonary hypertension plays a role of inhibition in the development of hypoxic pulmonary hypertension. Hemin has a therapeutic effect on hypoxic pulmonary hypertension.

  6. Neuroprotective Effect of Compound Anisodine in a Mouse Model with Chronic Ocular Hypertension

    Institute of Scientific and Technical Information of China (English)

    Wen-Dong Liu; Lan-Lan Chen; Ce-Ying Shen; Li-Bin Jiang

    2015-01-01

    Background:Compound anisodine (CA) is a compound preparation made from hydrobromide anisodine and procaine hydrochloride.The former is an M-choline receptor blocker with the function of regulating the vegetative nervous system,improving microcirculation,and so on.The latter is an antioxidant with the activities ofneuroprotection.This study aimed to investigate the potential neuroprotection of CA,which affects the degeneration of the retinal ganglion cells (RGCs) in an animal model with chronic ocular hypertension.Methods:Female C57BL/6J mice (n =24) were divided randomly into four groups:Normal control group without any treatment (Group A,n =6);CA control group with feeding the CA solution (Group B,n =6);microbeads (MBs) control group with injecting MB into the anterior chamber (Group C,n =6);CA study group with MB injection and with feeding the CA solution (Group D,n =6).Intraocular pressure (IOP) was measured every 3 days after MB injection.At the 21st day,neurons were retrograde-labeled by Fluoro-Gold (FG).Animals were sacrificed on the 27th day.Retinal flat mounts were stained immunohistologically by β-Ⅲ-tubulin.FG-retrograde-labeled RGCs,β-Ⅲ-tubulin-positive RGCs,and β-Ⅲ-tubulin-positive nerve fibers were quantified.Results:Mice of Groups C and D expressed the incidence of consistent IOP elevation,which is above the IOP level of Group A with the normal one.There is no significant difference in IOP between Groups A and B (P > 0.05).On the 27th day,there were distinct loss in stained RGCs and nerve fibers from Groups C and D compared with Group A (all P < 0.00l).The quantity was significantly higher in Group D as compared to Group C (all P < 0.00l) but lower than Group A (all P < 0.001).There was no significant difference in the quantity of RGCs and nerve fibers between Groups A and B (all P > 0.05).Conclusions:These findings suggest that CA plays an importantly neuroprotective role on RGCs in a mouse model with chronic ocular hypertension.

  7. Chronic methamphetamine treatment reduces the expression of synaptic plasticity genes and changes their DNA methylation status in the mouse brain.

    Science.gov (United States)

    Cheng, Min-Chih; Hsu, Shih-Hsin; Chen, Chia-Hsiang

    2015-12-10

    Methamphetamine (METH) is a highly addictive psychostimulant that may cause long-lasting synaptic dysfunction and abnormal gene expression. We aimed to explore the differential expression of synaptic plasticity genes in chronic METH-treated mouse brain. We used the RT(2) Profiler PCR Array and the real-time quantitative PCR to characterize differentially expressed synaptic plasticity genes in the frontal cortex and the hippocampus of chronic METH-treated mice compared with normal saline-treated mice. We further used pyrosequencing to assess DNA methylation changes in the CpG region of the five immediate early genes (IEGs) in chronic METH-treated mouse brain. We detected six downregulated genes in the frontal cortex and the hippocampus of chronic METH-treated mice, including five IEGs (Arc, Egr2, Fos, Klf10, and Nr4a1) and one neuronal receptor gene (Grm1), compared with normal saline-treated group, but only four genes (Arc, Egr2, Fos, and Nr4a1) were confirmed to be different. Furthermore, we found several CpG sites of the Arc and the Fos that had significant changes in DNA methylation status in the frontal cortex of chronic METH-treated mice, while the klf10 and the Nr4a1 that had significant changes in the hippocampus. Our results show that chronic administration of METH may lead to significant downregulation of the IEGs expression in both the frontal cortex and the hippocampus, which may partly account for the molecular mechanism of the action of METH. Furthermore, the changes in DNA methylation status of the IEGs in the brain indicate that an epigenetic mechanism-dependent transcriptional regulation may contribute to METH addiction, which warrants additional study. PMID:26496011

  8. [Hypoxic lung failure].

    Science.gov (United States)

    David, S; Wiesner, O

    2016-04-01

    Hypoxic lung failure is among the major indications for patients' referral to intensive care units either for surveillance or if necessary therapy. There are a vast number of pathophysiological causes of lung failure and the optimal treatment highly depends on the underlying pathology; therefore, no standard algorithm exists. So-called acute respiratory distress syndrome (ARDS) represents a very severe manifestation of hypoxemic lung failure that is of particular relevance for intensivists and is therefore the focus of this review. In addition to fundamental pathophysiology of lung injury, the article also focuses on established and modern treatment strategies. Moreover, we will briefly highlight innovative concepts of ARDS treatment that might become relevant in the future. PMID:27084180

  9. 慢性缺氧模型与病证相关性的研究进展%Advances on Correlation between Chronic Hypoxic Animal Models and Diseases and Syndromes

    Institute of Scientific and Technical Information of China (English)

    张洁琼; 柴程芝; 寇俊萍; 余伯阳

    2012-01-01

    Prolonged or repeated hypoxia can affect the normal oxygen supply for tissues and organs and normal physiological function of the cardiovascular, respiratory and nervous systems. Multi-system injuries bring serious harm to human health. Along with the modern life style and dietary structure change, deficiency of aerobic exercise and the worsening earth pollution and destruction make human in a chronic hypoxic environment imperceptibly. Therefore, it is of importance to pay more attention to the harm of chronic hypoxia and take corresponding prevention measures. Scholars at home and abroad largely explored constructing animal models to simulate different diseases and syndromes through observing macro and micro indications, including performance and physiological or biochemical indexes. And different oxygen cycles and different hypoxia intensities were used. Various animal models of chronic hypoxia have been commonly used to investigate the various physiological or pathological processes of hypoxia-related diseases including obstructive sleep apnea syndrome, pulmonary artery hypertension, cardiovascular diseases, neurodegenerative disease and Deficiency of both Qi and Yin syndrome, Stagnation of Qi and blood stasis. In this paper, the recent studies on relationship of chronic hypoxia model and the related diseases and syndromes were reviewed. It is inclined to provide some clues not only for selecting reasonable animal models simulating the clinical features of diseases and syndrome but also for evaluating the characters of drug action reasonably.%长期或反复处于缺氧状态,可以影响机体组织器官的正常供氧,使心血管、呼吸和神经等系统功能紊乱,从而诱导机体多系统损伤,严重危害人体健康.随着现代人生活方式以及饮食结构的改变,生活中有氧运动不足再加上地球污染与破坏逐年加剧,人类不知不觉地处在一个慢性缺氧的环境中.因此,了解并重视慢性缺氧对生理功能的

  10. Restorative effect of endurance exercise on behavioral deficits in the chronic mouse model of Parkinson's disease with severe neurodegeneration

    Directory of Open Access Journals (Sweden)

    Lau Yuen-Sum

    2009-01-01

    Full Text Available Abstract Background Animal models of Parkinson's disease have been widely used for investigating the mechanisms of neurodegenerative process and for discovering alternative strategies for treating the disease. Following 10 injections with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP, 25 mg/kg and probenecid (250 mg/kg over 5 weeks in mice, we have established and characterized a chronic mouse model of Parkinson's disease (MPD, which displays severe long-term neurological and pathological defects resembling that of the human Parkinson's disease in the advanced stage. The behavioral manifestations in this chronic mouse model of Parkinson's syndrome remain uninvestigated. The health benefit of exercise in aging and in neurodegenerative disorders including the Parkinson's disease has been implicated; however, clinical and laboratory studies in this area are limited. In this research with the chronic MPD, we first conducted a series of behavioral tests and then investigated the impact of endurance exercise on the identified Parkinsonian behavioral deficits. Results We report here that the severe chronic MPD mice showed significant deficits in their gait pattern consistency and in learning the cued version of the Morris water maze. Their performances on the challenging beam and walking grid were considerably attenuated suggesting the lack of balance and motor coordination. Furthermore, their spontaneous and amphetamine-stimulated locomotor activities in the open field were significantly suppressed. The behavioral deficits in the chronic MPD lasted for at least 8 weeks after MPTP/probenecid treatment. When the chronic MPD mice were exercise-trained on a motorized treadmill 1 week before, 5 weeks during, and 8–12 weeks after MPTP/probenecid treatment, the behavioral deficits in gait pattern, spontaneous ambulatory movement, and balance performance were reversed; whereas neuronal loss and impairment in cognitive skill, motor coordination, and

  11. Further development of a model of chronic bone marrow aplasia in the busulphan-treated mouse.

    Science.gov (United States)

    Turton, John A; Sones, William R; Andrews, Charles M; Pilling, Andrew M; Williams, Thomas C; Molyneux, Gemma; Rizzo, Sian; Gordon-Smith, Edward C; Gibson, Frances M

    2006-02-01

    Aplastic anaemia (AA) in man is an often fatal disease characterized by pancytopenia of the peripheral blood and aplasia of the bone marrow. AA is a toxic effect of many drugs and chemicals (e.g. chloramphenicol, azathioprine, phenylbutazone, gold salts, penicillamine and benzene). However, there are no widely used or convenient animal models of drug-induced AA. Recently, we reported a new model of chronic bone marrow aplasia (CBMA = AA) in the busulphan (BU)-treated mouse: eight doses of BU (10.50 mg/kg) were administered to female BALB/c mice over a period of 23 days; CBMA was evident at day 91/112 post-dosing with significantly reduced erythrocytes, platelets, leucocytes and nucleated bone marrow cell counts. However, mortality was high (49.3%). We have now carried out a study to modify the BU-dosing regime to induce CBMA without high mortality, and investigated the patterns of cellular responses in the blood and marrow in the post-dosing period. Mice (n = 64/65) were dosed 10 times with BU at 0 (vehicle control), 8.25, 9.0 and 9.75 mg/kg over 21 days and autopsied at day 1, 23, 42, 71, 84, 106 and 127 post-dosing (n = 7-15); blood and marrow samples were examined. BU induced a predictable bone marrow depression at day 1 post-dosing; at day 23/42 post-dosing, parameters were returning towards normal during a period of recovery. At day 71, 84, 106 and 127 post-dosing, a stabilized, late-stage, nondose-related CBMA was evident in BU-treated mice, with decreased erythrocytes, platelets and marrow cell counts, and increased MCV. At day 127 post-dosing, five BU-treated mice showed evidence of lymphoma. In this study, mortality was low, ranging from 3.1% (8.25 mg/kg BU) to 12.3% (9.75 mg/kg BU). It is concluded that BU at 9.0 mg/kg (or 9.25 mg/kg) is an appropriate dose level to administer (10 times over 21 days) to induce CBMA at approximately day 50-120 post-dosing.

  12. ENDURANCE EXERCISE PROMOTES CARDIORESPIRATORY REHABILITATION WITHOUT NEURORESTORATION IN THE CHRONIC MOUSE MODEL OF PARKINSONISM WITH SEVERE NEURODEGENERATION

    OpenAIRE

    Al-Jarrah, Muhammed; Pothakos, Konstantinos; Novikova, Lesya; Smirnova, Irina V; Kurz, Max J.; Stehno-Bittel, Lisa; Lau, Yuen-Sum

    2007-01-01

    Physical rehabilitation with endurance exercise for patients with Parkinson's disease has not been well established, although some clinical and laboratory reports suggest that exercise may produce neuroprotective effect and restore dopaminergic and motor functions. In this study, we used a chronic mouse model of Parkinsonism, which was induced by injecting male C57BL/6 mice with 10 doses of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (25 mg/kg) and probenecid (250 mg/kg) over five weeks. Thi...

  13. Hypoxic training methods for improving endurance exercise performance

    Directory of Open Access Journals (Sweden)

    Jacob A. Sinex

    2015-12-01

    Full Text Available Endurance athletic performance is highly related to a number of factors that can be altered through altitude and hypoxic training including increases in erythrocyte volume, maximal aerobic exercise capacity, capillary density, and economy. Physiological adaptations in response to acute and chronic exposure to hypoxic environments are well documented and range from short-term detrimental effects to longer-term adaptations that can improve performance at altitude and in sea-level competitions. Many altitude and hypoxic training protocols have been developed, employing various combinations of living and training at sea-level, low, moderate, and high altitudes and utilizing natural and artificial altitudes, with varying degrees of effectiveness. Several factors have been identified that are associated with individual responses to hypoxic training, and techniques for identifying those athletes most likely to benefit from hypoxic training continue to be investigated. Exposure to sufficiently high altitude (2000–3000 m for more than 12 h/day, while training at lower altitudes, for a minimum of 21 days is recommended. Timing of altitude training related to competition remains under debate, although general recommendations can be considered.

  14. Hypoxic preconditioning in an autohypoxic animal model

    Institute of Scientific and Technical Information of China (English)

    Guo Shao; Guo-Wei Lu

    2012-01-01

    Hypoxic preconditioning refers to the exposure of organisms,systems,organs,tissues or cells to moderate hypoxia/ischemia that [Results]in increased resistance to a subsequent episode of severe hypoxia/ischemia.In this article,we review recent research based on a mouse model of repeated exposure to autohypoxia.Pre-exposure markedly increases the tolerance to or protection against hypoxic insult,and preserves the cellular structure of the brain.Furthermore,the hippocampal activity amplitude and frequency of electroencephalogram,latency of cortical somatosensory-evoked potential and spinal somatosensory-evoked potential progressively decrease,while spatial learning and memory improve.In the brain,detrimental neurochemicals such as free radicals are down-regulated,while beneficial ones such as adenosine are upregulated.Also,antihypoxia factor(s) and gene(s) are activated.We propose that the tolerance and protective effects depend on energy conservation and plasticity triggered by exposure to hypoxia via oxygen-sensing transduction pathways and hypoxia-inducible factor-initiated cascades.A potential path for further research is the development of devices and pharmaceuticals acting on antihypoxia factor(s) and gene(s) for the prevention and treatment of hypoxia and related syndromes.

  15. Chronic Fluoxetine Induces the Enlargement of Perforant Path-Granule Cell Synapses in the Mouse Dentate Gyrus.

    Science.gov (United States)

    Kitahara, Yosuke; Ohta, Keisuke; Hasuo, Hiroshi; Shuto, Takahide; Kuroiwa, Mahomi; Sotogaku, Naoki; Togo, Akinobu; Nakamura, Kei-ichiro; Nishi, Akinori

    2016-01-01

    A selective serotonin reuptake inhibitor is the most commonly prescribed antidepressant for the treatment of major depression. However, the mechanisms underlying the actions of selective serotonin reuptake inhibitors are not fully understood. In the dentate gyrus, chronic fluoxetine treatment induces increased excitability of mature granule cells (GCs) as well as neurogenesis. The major input to the dentate gyrus is the perforant path axons (boutons) from the entorhinal cortex (layer II). Through voltage-sensitive dye imaging, we found that the excitatory neurotransmission of the perforant path synapse onto the GCs in the middle molecular layer of the mouse dentate gyrus (perforant path-GC synapse) is enhanced after chronic fluoxetine treatment (15 mg/kg/day, 14 days). Therefore, we further examined whether chronic fluoxetine treatment affects the morphology of the perforant path-GC synapse, using FIB/SEM (focused ion beam/scanning electron microscopy). A three-dimensional reconstruction of dendritic spines revealed the appearance of extremely large-sized spines after chronic fluoxetine treatment. The large-sized spines had a postsynaptic density with a large volume. However, chronic fluoxetine treatment did not affect spine density. The presynaptic boutons that were in contact with the large-sized spines were large in volume, and the volumes of the mitochondria and synaptic vesicles inside the boutons were correlated with the size of the boutons. Thus, the large-sized perforant path-GC synapse induced by chronic fluoxetine treatment contains synaptic components that correlate with the synapse size and that may be involved in enhanced glutamatergic neurotransmission. PMID:26788851

  16. Chronic Fluoxetine Induces the Enlargement of Perforant Path-Granule Cell Synapses in the Mouse Dentate Gyrus.

    Science.gov (United States)

    Kitahara, Yosuke; Ohta, Keisuke; Hasuo, Hiroshi; Shuto, Takahide; Kuroiwa, Mahomi; Sotogaku, Naoki; Togo, Akinobu; Nakamura, Kei-ichiro; Nishi, Akinori

    2016-01-01

    A selective serotonin reuptake inhibitor is the most commonly prescribed antidepressant for the treatment of major depression. However, the mechanisms underlying the actions of selective serotonin reuptake inhibitors are not fully understood. In the dentate gyrus, chronic fluoxetine treatment induces increased excitability of mature granule cells (GCs) as well as neurogenesis. The major input to the dentate gyrus is the perforant path axons (boutons) from the entorhinal cortex (layer II). Through voltage-sensitive dye imaging, we found that the excitatory neurotransmission of the perforant path synapse onto the GCs in the middle molecular layer of the mouse dentate gyrus (perforant path-GC synapse) is enhanced after chronic fluoxetine treatment (15 mg/kg/day, 14 days). Therefore, we further examined whether chronic fluoxetine treatment affects the morphology of the perforant path-GC synapse, using FIB/SEM (focused ion beam/scanning electron microscopy). A three-dimensional reconstruction of dendritic spines revealed the appearance of extremely large-sized spines after chronic fluoxetine treatment. The large-sized spines had a postsynaptic density with a large volume. However, chronic fluoxetine treatment did not affect spine density. The presynaptic boutons that were in contact with the large-sized spines were large in volume, and the volumes of the mitochondria and synaptic vesicles inside the boutons were correlated with the size of the boutons. Thus, the large-sized perforant path-GC synapse induced by chronic fluoxetine treatment contains synaptic components that correlate with the synapse size and that may be involved in enhanced glutamatergic neurotransmission.

  17. Mitogen-Activated Protein Kinases and Hypoxic/Ischemic Nephropathy

    Directory of Open Access Journals (Sweden)

    Fengbao Luo

    2016-08-01

    Full Text Available Tissue hypoxia/ischemia is a pathological feature of many human disorders including stroke, myocardial infarction, hypoxic/ischemic nephropathy, as well as cancer. In the kidney, the combination of limited oxygen supply to the tissues and high oxygen demand is considered the main reason for the susceptibility of the kidney to hypoxic/ischemic injury. In recent years, increasing evidence has indicated that a reduction in renal oxygen tension/blood supply plays an important role in acute kidney injury, chronic kidney disease, and renal tumorigenesis. However, the underlying signaling mechanisms, whereby hypoxia alters cellular behaviors, remain poorly understood. Mitogen-activated protein kinases (MAPKs are key signal-transducing enzymes activated by a wide range of extracellular stimuli, including hypoxia/ischemia. There are four major family members of MAPKs: the extracellular signal-regulated kinases-1 and -2 (ERK1/2, the c-Jun N-terminal kinases (JNK, p38 MAPKs, and extracellular signal-regulated kinase-5 (ERK5/BMK1. Recent studies, including ours, suggest that these MAPKs are differentially involved in renal responses to hypoxic/ischemic stress. This review will discuss their changes in hypoxic/ischemic pathophysiology with acute kidney injury, chronic kidney diseases and renal carcinoma.

  18. Chronic treatment with the GLP1 analogue liraglutide increases cell proliferation and differentiation into neurons in an AD mouse model.

    Directory of Open Access Journals (Sweden)

    Vadivel Parthsarathy

    Full Text Available Neurogenesis is a life long process, but the rate of cell proliferation and differentiation decreases with age. In Alzheimer's patients, along with age, the presence of Aβ in the brain inhibits this process by reducing stem cell proliferation and cell differentiation. GLP-1 is a growth factor that has neuroprotective properties. GLP1 receptors are present on neuronal progenitor cells, and the GLP-1 analogue liraglutide has been shown to increase cell proliferation in an Alzheimer's disease (AD mouse model. Here we investigated acute and chronic effects of liraglutide on progenitor cell proliferation, neuroblast differentiation and their subsequent differentiation into neurons in wild type and APP/PS-1 mice at different ages. APP/PS1 and their littermate controls, aged 3, 6, 12, 15 months were injected acutely or chronically with 25 nmol/kg liraglutide. Acute treatment with liraglutide showed an increase in cell proliferation in APP/PS1 mice, but not in controls whereas chronic treatment increased cell proliferation at all ages (BrdU and Ki67 markers. Moreover, numbers of immature neurons (DCX were increased in both acute and chronic treated animals at all ages. Most newly generated cells differentiated into mature neurons (NeuN marker. A significant increase was observed with chronically treated 6, 12, 15 month APP/PS1 and WT groups. These results demonstrate that liraglutide, which is currently on the market as a treatment for type 2 diabetes (Victoza(TM, increases neurogenesis, which may have beneficial effects in neurodegenerative disorders like AD.

  19. L-tyrosine improves neuroendocrine function in a mouse model of chronic stress

    Institute of Scientific and Technical Information of China (English)

    Zhihua Wang; Jinghua Li; Zhiming Wang; Lingyan Xue; Yi Zhang; Yingjie Chen; Jun Su; Zhongming Li

    2012-01-01

    Adult BALB/c mice, individually housed, were stimulated with nine different stressors, arranged randomly, for 4 continuous weeks to generate an animal model of chronic stress. In chronically stressed mice, spontaneous locomotor activity was significantly decreased, escape latency in the Morris water maze test was prolonged, serum levels of total thyrotropin and total triiodothyronine were significantly decreased, and dopamine and norepinephrine content in the pallium, hippocampus and hypothalamus were significantly reduced. All of these changes were suppressed, to varying degrees, by L-tyrosine supplementation. These findings indicate that the neuroendocrine network plays an important role in chronic stress, and that L-tyrosine supplementation has therapeutic effects.

  20. Longitudinal study of a mouse model of chronic pulmonary inflammation using breath hold gated micro-CT

    International Nuclear Information System (INIS)

    To evaluate the feasibility of using automatic quantitative analysis of breath hold gated micro-CT images to detect and monitor disease in a mouse model of chronic pulmonary inflammation, and to compare image-based measurements with pulmonary function tests and histomorphometry. Forty-nine A/J mice were used, divided into control and inflammation groups. Chronic inflammation was induced by silica aspiration. Fourteen animals were imaged at baseline, and 4, 14, and 34 weeks after silica aspiration, using micro-CT synchronized with ventilator-induced breath holds. Lung input impedance was measured as well using forced oscillation techniques. Five additional animals from each group were killed after micro-CT for comparison with histomorphometry. At all time points, micro-CT measurements show statistically significant differences between the two groups, while first differences in functional test parameters appear at 14 weeks. Micro-CT measurements correlate well with histomorphometry and discriminate diseased and healthy groups better than functional tests. Longitudinal studies using breath hold gated micro-CT are feasible on the silica-induced model of chronic pulmonary inflammation, and automatic measurements from micro-CT images correlate well with histomorphometry, being more sensitive than functional tests to detect lung damage in this model. (orig.)

  1. Longitudinal study of a mouse model of chronic pulmonary inflammation using breath hold gated micro-CT

    Energy Technology Data Exchange (ETDEWEB)

    Artaechevarria, Xabier; Perez-Martin, Daniel; Munoz-Barrutia, Arrate; Ortiz-de-Solorzano, Carlos [Center for Applied Medical Research, University of Navarra, Cancer Imaging Laboratory, Oncology Division, Pamplona (Spain); Blanco, David; Biurrun, Gabriel de; Montuenga, Luis M. [Center for Applied Medical Research, University of Navarra, Biomarkers Laboratory, Pamplona (Spain); Torres, Juan P. de; Zulueta, Javier J. [Clinica Universidad de Navarra, Pneumology Department, Pamplona (Spain); Bastarrika, Gorka [Clinica Universidad de Navarra, Radiology Department, Pamplona (Spain)

    2010-11-15

    To evaluate the feasibility of using automatic quantitative analysis of breath hold gated micro-CT images to detect and monitor disease in a mouse model of chronic pulmonary inflammation, and to compare image-based measurements with pulmonary function tests and histomorphometry. Forty-nine A/J mice were used, divided into control and inflammation groups. Chronic inflammation was induced by silica aspiration. Fourteen animals were imaged at baseline, and 4, 14, and 34 weeks after silica aspiration, using micro-CT synchronized with ventilator-induced breath holds. Lung input impedance was measured as well using forced oscillation techniques. Five additional animals from each group were killed after micro-CT for comparison with histomorphometry. At all time points, micro-CT measurements show statistically significant differences between the two groups, while first differences in functional test parameters appear at 14 weeks. Micro-CT measurements correlate well with histomorphometry and discriminate diseased and healthy groups better than functional tests. Longitudinal studies using breath hold gated micro-CT are feasible on the silica-induced model of chronic pulmonary inflammation, and automatic measurements from micro-CT images correlate well with histomorphometry, being more sensitive than functional tests to detect lung damage in this model. (orig.)

  2. Chronic low-dose-rate ionising radiation affects the hippocampal phosphoproteome in the ApoE−/− Alzheimer mouse model

    DEFF Research Database (Denmark)

    Kempf, Stefan; Janik, Dirk; Barjaktarovic, Zarko;

    2016-01-01

    Accruing data indicate that radiation-induced consequences resemble pathologies of neurodegenerative diseases such as Alzheimer´s. The aim of this study was to elucidate the effect on hippocampus of chronic low-dose-rate radiation exposure (1 mGy/day or 20 mGy/day) given over 300 days with cumula......Accruing data indicate that radiation-induced consequences resemble pathologies of neurodegenerative diseases such as Alzheimer´s. The aim of this study was to elucidate the effect on hippocampus of chronic low-dose-rate radiation exposure (1 mGy/day or 20 mGy/day) given over 300 days...... with cumulative doses of 0.3 Gy and 6.0 Gy, respectively. ApoE deficient mutant C57Bl/6 mouse was used as an Alzheimer´s model. Using mass spectrometry, a marked alteration in the phosphoproteome was found at both dose rates. The radiation-induced changes in the phosphoproteome were associated with the control...... that several molecular targets induced by chronic low-dose-rate radiation overlap with those of Alzheimer´s pathology. It may suggest that ionising radiation functions as a contributing risk factor to this neurodegenerative disease....

  3. L-tyrosine improves neuroendocrine function in a mouse model of chronic stress

    OpenAIRE

    Wang, Zhihua; Li, Jinghua; Wang, Zhiming; Xue, Lingyan; Zhang, Yi; Chen, Yingjie; Su, Jun; Li, Zhongming

    2012-01-01

    Adult BALB/c mice, individually housed, were stimulated with nine different stressors, arranged randomly, for 4 continuous weeks to generate an animal model of chronic stress. In chronically stressed mice, spontaneous locomotor activity was significantly decreased, escape latency in the Morris water maze test was prolonged, serum levels of total thyrotropin and total triiodothyronine were significantly decreased, and dopamine and norepinephrine content in the pallium, hippocampus and hypothal...

  4. Chronic Intake of Japanese Sake Mediates Radiation-Induced Metabolic Alterations in Mouse Liver.

    Directory of Open Access Journals (Sweden)

    Tetsuo Nakajima

    Full Text Available Sake is a traditional Japanese alcoholic beverage that is gaining popularity worldwide. Although sake is reported to have beneficial health effects, it is not known whether chronic sake consumption modulates health risks due to radiation exposure or other factors. Here, the effects of chronic administration of sake on radiation-induced metabolic alterations in the livers of mice were evaluated. Sake (junmai-shu was administered daily to female mice (C3H/He for one month, and the mice were exposed to fractionated doses of X-rays (0.75 Gy/day for the last four days of the sake administration period. For comparative analysis, a group of mice were administered 15% (v/v ethanol in water instead of sake. Metabolites in the liver were analyzed by capillary electrophoresis-time-of-flight mass spectrometry one day following the last exposure to radiation. The metabolite profiles of mice chronically administered sake in combination with radiation showed marked changes in purine, pyrimidine, and glutathione (GSH metabolism, which were only partially altered by radiation or sake administration alone. Notably, the changes in GSH metabolism were not observed in mice treated with radiation following chronic administration of 15% ethanol in water. Changes in several metabolites, including methionine and valine, were induced by radiation alone, but were not detected in the livers of mice who received chronic administration of sake. In addition, the chronic administration of sake increased the level of serum triglycerides, although radiation exposure suppressed this increase. Taken together, the present findings suggest that chronic sake consumption promotes GSH metabolism and anti-oxidative activities in the liver, and thereby may contribute to minimizing the adverse effects associated with radiation.

  5. Computer mouse use predicts acute pain but not prolonged or chronic pain in the neck and shoulder

    DEFF Research Database (Denmark)

    Gerster, Mette; Grimstrup, S; Lassen, C F;

    2008-01-01

    BACKGROUND: Computer use may have an adverse effect on musculoskeletal outcomes. This study assessed the risk of neck and shoulder pain associated with objectively recorded professional computer use. METHODS: A computer programme was used to collect data on mouse and keyboard usage and weekly...... reports of neck and shoulder pain among 2146 technical assistants. Questionnaires were also completed at baseline and at 12 months. The three outcome measures were: (1) acute pain (measured as weekly pain); (2) prolonged pain (no or minor pain in the neck and shoulder region over four consecutive weeks...... followed by three consecutive weeks with a high pain score); and (3) chronic pain (reported pain or discomfort lasting more than 30 days and "quite a lot of trouble" during the past 12 months). RESULTS: Risk for acute neck pain and shoulder pain increased linearly by 4% and 10%, respectively, for each...

  6. The effects of chronic social defeat stress on mouse self-grooming behavior and its patterning.

    Science.gov (United States)

    Denmark, Ashley; Tien, David; Wong, Keith; Chung, Amanda; Cachat, Jonathan; Goodspeed, Jason; Grimes, Chelsea; Elegante, Marco; Suciu, Christopher; Elkhayat, Salem; Bartels, Brett; Jackson, Andrew; Rosenberg, Michael; Chung, Kyung Min; Badani, Hussain; Kadri, Ferdous; Roy, Sudipta; Tan, Julia; Gaikwad, Siddharth; Stewart, Adam; Zapolsky, Ivan; Gilder, Thomas; Kalueff, Allan V

    2010-04-01

    Stress induced by social defeat is a strong modifier of animal anxiety and depression-like phenotypes. Self-grooming is a common rodent behavior, and has an ordered cephalo-caudal progression from licking of the paws to head, body, genitals and tail. Acute stress is known to alter grooming activity levels and disrupt its patterning. Following 15-17 days of chronic social defeat stress, grooming behavior was analyzed in adult male C57BL/6J mice exhibiting either dominant or subordinate behavior. Our study showed that subordinate mice experience higher levels of anxiety and display disorganized patterning of their grooming behaviors, which emerges as a behavioral marker of chronic social stress. These findings indicate that chronic social stress modulates grooming behavior in mice, thus illustrating the importance of grooming phenotypes for neurobehavioral stress research.

  7. Effects of chronic intermittent hypoxia on the cognitive function and neuron structure of hippocampus in mouse model of Parkinson's disease

    Directory of Open Access Journals (Sweden)

    LIU Hai-lin

    2013-06-01

    Full Text Available Objective To investigate the effects of chronic intermittent hypoxia (CIH on the cognitive function, neuron structure and synaptophysin (Syn expression of the hippocampus in mouse model of Parkinson's disease (PD. Methods A hypoxia-reoxygen device was used to prepare the model of CIH. Meanwhile, the PD mouse model was built by intraperitoneal injection of paraquat (PQ. The cognitive function was evaluated by Y-type electric maze and step-down test. Syn expression in the hippocampus was estimated by immunohistochemistry. The neuron structure in the hippocampus was observed by HE staining, Nissl staining and the electron microscope. Results Comparing to control group, a significant decrease was found in learning and memorizing performance (P < 0.05, for all and the amount of neuron, while a significant increase was seen in total reaction time (TRT and error reaction (ER in Y-type electric maze and step-down test and the gray value of Syn in the hippocampus in PQ, CIH, and PQ + CIH groups. Various degrees of anomaly were observed in neuron structure of hippocampus by HE staining, Nissl staining and electron microscopy in PQ, CIH, and PQ + CIH groups, while presented most obviously in thelatter group. Conclusion The PQ-induced impairment of cognitive function in PD model mice was aggravated by CIH, which may be related to the damage of neuron structure and the decrease of synaptic function in hippocampus.

  8. Fasting reduces liver fibrosis in a mouse model for chronic cholangiopathies

    NARCIS (Netherlands)

    Sokolovic, Aleksandar; van Roomen, Cindy P. A. A.; Ottenhoff, Roelof; Scheij, Saskia; Hiralall, Johan K.; Claessen, Nike; Aten, Jan; Elferink, Ronald P. J. Oude; Groen, Albert K.; Sokolovic, Milka

    2013-01-01

    Chronic cholangiopathies often lead to fibrosis, as a result of a perpetuated wound healing response, characterized by increased inflammation and excessive deposition of proteins of the extracellular matrix. Our previous studies have shown that food deprivation suppresses the immune response, which

  9. Chronic ethanol exposure inhibits distraction osteogenesis in a mouse model: role of the TNF signaling axis

    Science.gov (United States)

    Tumor necrosis factor-alpha (TNF-alpha) is an inflammatory cytokine that modulates osteoblastogenesis. In addition, the demonstrated inhibitory effects of chronic ethanol exposure on direct bone formation in rats are hypothetically mediated by TNF-alpha signaling. The effects in mice are unreported....

  10. Weaver mutant mouse cerebellar granule cells respond normally to chronic depolarization

    DEFF Research Database (Denmark)

    Bjerregaard, Annette; Mogensen, Helle Smidt; Hack, N;

    1997-01-01

    We studied the effects of chronic K(+)-induced membrane depolarization and treatment with N-methyl-D-aspartate (NMDA) on cerebellar granule cells (CGCs) from weaver mutant mice and non-weaver litter-mates. The weaver mutation is a Gly-to-Ser substitution in a conserved region of the Girk2 G prote...

  11. 慢性间歇低氧对大鼠肝细胞SOCS3表达的影响%The effect of SOCS3 expression on rat liver cells by chronic intermittent hypoxic

    Institute of Scientific and Technical Information of China (English)

    任寿安; 康耀文; 蔡月伟

    2014-01-01

    Objective To established chronic intermittent hypoxic (CIH) animal model for investigate the mechanism of insulin resistance caused by CIH.Methods Twenty-four healthy male SD rats were randomly divided into four groups:normal control group (NC group),CIH 2 weeks group (CIH2 group),and CIH 5 weeks group (CIH5 group),with 8 rats in each group.The minimum oxygen concentration was 6%-7% in animal chamber.About 8 hours per day (from 9AM to 5 PM),the experimental lasted for 35 days.The rats in control group were placed in the same animal box without CIH.After the experiment,to measure fasting blood glucose and insulin levels by radioimmunoassay and then according to the homeostasis model of insulin resistance index (HOMA) was calculated.The expressions of SOCS3 protein were detected with immunohistochemical method in rat liver cells.To detect the SOCS3-mRNA gene expression by reverse transcription and polymerase chain reaction (RT-PCR).Results Compared with the NC group,fasting blood glucose(F =33.582,P <0.05),insulin level (F =35.633,P <0.05) and HOMA-IR (F =49.045,P <0.05) of the CIH2.CIH5 group was higher than other groups (P <0.05).Compared with the NC group,the expression of SOCS3 protein was increased in CIH2 and CHI5 group (F =9.472,P <0.05),but in CIH2 and CIH5 group were no significantly differences (P >0.05).And then the expression of SOCS3-mRNA in CIH5 was higher than CIH2 and CIH5 group (F =8.665,P < 0.05).Pearson correlation analysis showed that HOMA-IR and the expression of SOCS3 protein was negatively correlated (r =-0.759,P <0.001) and was positively correlated with SOCS3-mRNA (r =0.603,P =0.01).Conclusions ①CIH exposure caused fasting blood glucose level and increase insulin level and insulin resistance in rats with CIH.With the intermittent hypoxic exposure time prolonged,the degree of insulin resistance was increased.②CIH leads to increased expression of SOCS3 protein and SOCS3-mRNA gene in rat liver cells with CIH exposure

  12. Influence of chronic ethanol intake on mouse synaptosomal aspartyl aminopeptidase and aminopeptidase A: relationship with oxidative stress indicators.

    Science.gov (United States)

    Mayas, María Dolores; Ramírez-Expósito, María Jesús; García, María Jesús; Carrera, María Pilar; Martínez-Martos, José Manuel

    2012-08-01

    Aminopeptidase A (APA) and aspartyl aminopeptidase (ASAP) not only act as neuromodulators in the regional brain renin-angiotensin system, but also release N-terminal acidic amino acids (glutamate and aspartate). The hyperexcitability of amino acid neurotransmitters is responsible for several neurodegenerative processes affecting the central nervous system. The purpose of the present work was to study the influence of chronic ethanol intake, a well known neurotoxic compound, on APA and ASAP activity under resting and K(+)-stimulated conditions at the synapse level. APA and ASAP activity were determined against glutamate- and aspartate-β-naphthylamide respectively in mouse frontal cortex synaptosomes and in their incubation supernatant in a Ca(2+)-containing or Ca(2+)-free artificial cerebrospinal fluid. The neurotoxic effects were analyzed by determining free radical generation, peroxidation of membrane lipids and the oxidation of synaptosomal proteins. In addition, the bioenergetic behavior of synaptosomes was analyzed under different experimental protocols. We obtained several modifications in oxidative stress parameters and a preferential inhibitor effect of chronic ethanol intake on APA and ASAP activities. Although previous in vitro studies failed to show signs of neurodegeneration, these in vivo modifications in oxidative stress parameters do not seem to be related to changes in APA and ASAP, invalidating the idea that an excess of free acidic amino acids released by APA and ASAP induces neurodegeneration.

  13. Astrocytic adaptation during cerebral angiogenesis follows the new vessel formation induced through chronic hypoxia in adult mouse cortex

    Science.gov (United States)

    Masamoto, Kazuto; Kanno, Iwao

    2014-03-01

    We examined longitudinal changes of the neuro-glia-vascular unit during cerebral angiogenesis induced through chronic hypoxia in the adult mouse cortex. Tie2-GFP mice in which the vascular endothelial cells expressed green fluorescent proteins (GFP) were exposed to chronic hypoxia, while the spatiotemporal developments of the cortical capillary sprouts and the neighboring astrocytic remodeling were characterized with repeated two-photon microscopy. The capillary sprouts appeared at early phases of the hypoxia adaptation (1-2 weeks), while the morphological changes of the astrocytic soma and processes were not detected in this phase. In the later phases of the hypoxia adaptation (> 2 weeks), the capillary sprouts created a new connection with existing capillaries, and its neighboring astrocytes extended their processes to the newly-formed vessels. The findings show that morphological adaptation of the astrocytes follow the capillary development during the hypoxia adaptation, which indicate that the newly-formed vessels provoke cellular interactions with the neighboring astrocytes to strengthen the functional blood-brain barrier.

  14. Deficiency in mouse hyaluronidase 2: a new mechanism of chronic thrombotic microangiopathy.

    OpenAIRE

    Onclinx, Cecile; Dogne, Sophie; Jadin, Laurence; Andris, Fabienne; Grandfils, Christian; Jouret, François; Mullier, Francois; Flamion, Bruno

    2015-01-01

    Hyaluronan is a major component of the extracellular matrix and glycocalyx. Its main somatic degrading enzymes are the hyaluronidases 1 and 2, none of which is active in the bloodstream. We generated hyaluronidase 2 deficient mice. They suffer from mild chronic anemia and thrombocytopenia, in parallel with a 10-fold increase in plasma hyaluronan concentration. The current study explores the mechanism of these hematological anomalies. The decreased erythrocyte and platelet counts were assigned...

  15. Chronic amiodarone remodels expression of ion channel transcripts in the mouse heart

    Institute of Scientific and Technical Information of China (English)

    S.LEBOUTER; A.ELHARCHI; C.MARIONNEAU; C.BELLOCQ; A.CHAMBELLAN; K.LEQUANG; JCBELLOCQ; JCCHEVALIER; GLANDE; JJLEGER; FCHARPENTIER; DESCANDE; SDEMOLOMBE

    2004-01-01

    AIM: The basis for the unique effectiveness of chronic amiodarone on cardiac arrhythmias is incompletely understood. The present study investigated the pharmacogenomics profile of amiodarone on genes encoding ion channel subunits. METHODS AND RESULTS: Adult male mice were treated for 6 weeks with vehicle or oral amiodarone at 30,90,or 180 mg·kg-1·d-1, Plasma and myocardial levels of amiodarone and n-desethyl-amiodarone in

  16. The development and characterization of two types of chronic responses in irradiated mouse colon

    International Nuclear Information System (INIS)

    The hypothesis to be tested is that there are two distinct types of chronic responses in irradiated normal tissues, each resulting from damage to different cell populations in the tissue. The first is a sequela of chronic epithelial depletion in which the tissue's integrity cannot be maintained. The other response is due to cell loss in the connective tissue and/or vascular stroma, i.e. a 'primary' chronic response. The purpose of this study was to test the hypothesis in the murine colon by first, establishing a model of each chronic response and then, by determining whether the responses differed in timing of expression, histology, and expression of specific collagen types. The model of late damage used was colonic obstructions/strictures induced by a single dose of 27 Gy ('consequential' response) and two equal doses of 14.75 Gy (t = 10 days) ('primary' response). 'Consequential' lesions appeared as early as 5 weeks after 27 Gy and were characterized by a deep mucosal ulceration and a thickened fibrotic serosa containing excessive accumulations of collagen types I and III. Both types were commingled in the scar at the base of the ulcer. Fibroblasts were synthesizing pro-collagen types I and III mRNA 10 weeks prior to measurable increases in collagen. A significant decrease in the ratio of collagen types I:III was associated with the 'consequential' response at 4-5 months post-irradiation. The 'primary' response, on the other hand, did not appear until 40 weeks after the split dose even though the total dose delivered was approximately the same as that for the 'consequential' response. The 'primary' response was characterized with an intact mucosa and a thickened fibrotic submucosa which contained excessive amounts of only collagen type I. An increased number of fibroblasts were synthesizing pro-collagen type I mRNA nearly 25 weeks before collage type I levels were increased

  17. Chronic Citalopram Administration Causes a Sustained Suppression of Serotonin Synthesis in the Mouse Forebrain

    OpenAIRE

    Gerard Honig; Jongsma, Minke E.; Marieke C G van der Hart; Tecott, Laurence H.

    2009-01-01

    BACKGROUND: Serotonin (5-HT) is a neurotransmitter with important roles in the regulation of neurobehavioral processes, particularly those regulating affect in humans. Drugs that potentiate serotonergic neurotransmission by selectively inhibiting the reuptake of serotonin (SSRIs) are widely used for the treatment of psychiatric disorders. Although the regulation of serotonin synthesis may be an factor in SSRI efficacy, the effect of chronic SSRI administration on 5-HT synthesis is not well un...

  18. Altered colonic function and microbiota profile in a mouse model of chronic depression

    OpenAIRE

    Park, A J; Collins, J.; BLENNERHASSETT, P. A.; Ghia, J E; Verdu, E. F.; Bercik, P; COLLINS, S. M.

    2013-01-01

    Background Depression often coexists with the irritable bowel syndrome (IBS) which is characterized by alterations in gut function. There is emerging evidence that the microbial composition (microbiota) of the gut is altered in IBS, but the basis for this is poorly understood. The aim of this study was to determine whether the induction of chronic depression results in changes in the colonic function and in its microbial community, and to explore underlying mechanisms. Methods Bilateral olfac...

  19. The influence of chronic ibuprofen treatment on proteins expressed in the mouse hippocampus.

    Science.gov (United States)

    Matsuura, Kenji; Otani, Mieko; Takano, Masaoki; Kadoyama, Keiichi; Matsuyama, Shogo

    2015-04-01

    Ibuprofen is a nonsteroidal anti-inflammatory drug (NSAID), treatment with which has been shown to delay the onset, slows the cognitive decline, and decreases the incidence of Alzheimer׳s disease (AD) in epidemiological and clinical studies. However, a comprehensive understanding of its mechanism of action remains unclear. To elucidate the prophylactic effect of ibuprofen on the onset of the learning and memory disturbances of AD, we performed proteomic analysis of the hippocampus of chronic ibuprofen-treated mice using two-dimensional gel electrophoresis (2-DE) followed by mass spectrometry. Twenty-eight proteins and seven phosphoproteins were identified to be significantly changed in the hippocampus of chronic ibuprofen-treated mice: translationally controlled tumor protein, thioredoxin-dependent peroxide reductase, and peroxiredoxin 6 were increased, and glial fibrillary acidic protein, dihydropyrimidinase-related protein 2, EF-hand domain-containing protein D2, and 14-3-3ζ were decreased. These identified proteins and phosphoproteins could be classified as cytoskeletal, neuronal development, chaperone, metabolic, apoptosis, neurotransmitter release, ATP synthase, deubiquitination, proteasome, NOS inhibitor, adapter, vesicle transport, signal transduction, antioxidant enzyme, proton transport, synaptogenesis, and serine/threonine phosphatase types. Western blot analysis showed the changes in dihydropyrimidinase-related protein 2, heat shock protein 8, ubiquitin carboxyl-terminal hydrolase PGP9.5, and γ-enolase levels in the hippocampus of chronic ibuprofen-treated mice. These findings showed that the chronic treatment with ibuprofen changed the levels of some proteins and phosphoproteins in the hippocampus. We propose that these identified proteins and phosphoproteins play an important role in decreasing the incidence of AD, especially impaired learning and memory functions.

  20. microRNA regulation of the embryonic hypoxic response in Caenorhabditis elegans.

    Science.gov (United States)

    Kagias, Konstantinos; Pocock, Roger

    2015-01-01

    Layered strategies to combat hypoxia provide flexibility in dynamic oxygen environments. Here we show that multiple miRNAs are required for hypoxic survival responses during C. elegans embryogenesis. Certain miRNAs promote while others antagonize the hypoxic survival response. We found that expression of the mir-35 family is regulated by hypoxia in a HIF-1-independent manner and loss of mir-35-41 weakens hypoxic survival mechanisms in embryos. In addition, correct regulation of the RNA binding protein, SUP-26, a mir-35 family target, is needed for survival in chronic hypoxia. The identification of the full mRNA target repertoire of these miRNAs will reveal the miRNA-regulated network of hypoxic survival mechanisms in C. elegans. PMID:26063315

  1. Nicotinamide and other benzamide analogs as agents for overcoming hypoxic cell radiation resistance in tumours

    International Nuclear Information System (INIS)

    Oxygen deficient hypoxic cells, which are resistant to sparsely ionising radiation, have now been identified in most animal and some human solid tumours and will influence the response of those tumours to radiation treatment. This hypoxia can be either chronic, arising from an oxygen diffusion limitation, or acute, resulting from transient stoppages in microregional blood flow. Extensive experimental studies, especially in the last decade, have shown that nicotinamide and structurally related analogs can effectively sensitize murine tumours to both single and fractionated radiation treatments and that they do so in preference to the effects seen in mouse normal tissues. The earliest studies suggested that this enhancement of radiation damage was the result of an inhibition of the repair mechanisms. However, recent studies in mouse tumours have shown that these drugs prevent transient cessations in blood flow, thus inhibiting the development of acute hypoxia. This novel discovery led to the suggestion that the potential role of these agents as radiosensitizers would be when combined with treatments that overcame chronic hypoxia. The combined nicotinamide with hyperthermia proved that the enhancement of radiation damage by both agents together was greater than that seen with each agent alone. Similar results were later seen for nicotinamide combined with a perfluorochemical emulsion, carbogen breathing, and pentoxifylline, and in all these studies the effects in tumours were always greater than those seen in appropriate normal tissues. Of all the analogs, it is nicotinamide itself which has been the most extensively studied as a radiosensitizer in vivo and the one that shows the greatest effect in animal tumours. It is also an agent that has been well established clinically, with daily doses of up to 6 g, associated with a low incidence of side effects. This human dose is equivalent to 100-200 mg/kg in mice and such doses will maximally sensitize murine tumours to

  2. The influence of chronic nicotine treatment on proteins expressed in the mouse hippocampus and cortex.

    Science.gov (United States)

    Matsuura, Kenji; Otani, Mieko; Takano, Masaoki; Kadoyama, Keiichi; Matsuyama, Shogo

    2016-06-01

    Chronic treatment with nicotine, the primary psychoactive substance in tobacco smoke, affects central nervous system functions, such as synaptic plasticity. Here, to clarify the effects of chronic nicotine treatment on the higher brain functions, proteomic analysis of the hippocampus and cortex of mice treated for 6 months with nicotine was performed using two-dimensional gel electrophoresis (2-DE) followed by mass spectrometry. There was significant change in the expression of 16 proteins and one phosphoprotein in the hippocampus (increased tubulin β-5, atp5b, MDH1, cytochrome b-c1 complex subunit 1, Hsc70, dynamin, profilin-2, 4-aminobutyrate aminotransferase, mitochondrial isoform 1 precursor, calpain small subunit 1, and vacuolar adenosine triphosphatase subunit B and decreased γ-actin, α-tubulin isotype M-α-2, putative β-actin, tubulin β-2A, NDUFA10, and G6PD) and 24 proteins and two phosphoproteins in the cortex (increased spectrin α chain, non-erythrocytic 1 isoform 1, tubulin β-5, γ-actin, creatine kinase B-type, LDH-B, secernin-1, UCH-L1, 14-3-3 γ, type II peroxiredoxin 1, PEBP-1, and unnamed protein product and decreased tubulin α-1C, α-internexin, γ-enolase, PDHE1-B, DPYL2, vacuolar adenosine triphosphatase subunit A, vacuolar adenosine triphosphatase subunit B, TCTP, NADH dehydrogenase Fe-S protein 1, protein disulfide-isomerase A3, hnRNP H2, γ-actin, atp5b, and unnamed protein product). Additionally, Western blotting validated the changes in dynamin, Hsc70, MDH1, NDUFA10, α-internexin, tubulin β-5 chain, and secernin-1. Thus, these findings indicate that chronic nicotine treatment changes the expression of proteins and phosphoproteins in the hippocampus and cortex. We propose that effect of smoking on higher brain functions could be mediated by alterations in expression levels of these proteins. PMID:26988295

  3. Thioredoxin-1 protects against neutrophilic inflammation and emphysema progression in a mouse model of chronic obstructive pulmonary disease exacerbation.

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    Naoya Tanabe

    Full Text Available BACKGROUND: Exacerbations of chronic obstructive pulmonary disease (COPD are characterized by acute enhancement of airway neutrophilic inflammation under oxidative stress and can be involved in emphysema progression. However, pharmacotherapy against the neutrophilic inflammation and emphysema progression associated with exacerbation has not been established. Thioredoxin-1 has anti-oxidative and anti-inflammatory properties and it can ameliorate neutrophilic inflammation through anti-chemotactic effects and prevent cigarette smoke (CS-induced emphysema. We aimed to determine whether thioredoxin-1 can suppress neutrophilic inflammation and emphysema progression in a mouse model of COPD exacerbation and if so, to reveal the underlying mechanisms. RESULTS: Mice were exposed to CS and then challenged with polyinosine-polycytidylic acid [poly(I:C], an agonist for virus-induced innate immunity. Airway neutrophilic inflammation, oxidative stress and lung apoptosis were enhanced in smoke-sensitive C57Bl/6, but not in smoke-resistant NZW mice. Exposure to CS and poly(I:C challenge accelerated emphysema progression in C57Bl/6 mice. Thioredoxin-1 suppressed neutrophilic inflammation and emphysema progression. Poly(I:C caused early neutrophilic inflammation through keratinocyte-derived chemokine and granulocyte-macrophage colony-stimulating factor (GM-CSF release in the lung exposed to CS. Late neutrophilic inflammation was caused by persistent GM-CSF release, which thioredoxin-1 ameliorated. Thioredoxin-1 enhanced pulmonary mRNA expression of MAP kinase phosphatase 1 (MKP-1, and the suppressive effects of thioredoxin-1 on prolonged GM-CSF release and late neutrophilic inflammation disappeared by inhibiting MKP-1. CONCLUSION: Using a mouse model of COPD exacerbation, we demonstrated that thioredoxin-1 ameliorated neutrophilic inflammation by suppressing GM-CSF release, which prevented emphysema progression. Our findings deepen understanding of the mechanisms

  4. Perinatal Hypoxic-Ischemic Encephalopathy

    OpenAIRE

    Ming-Chi Lai; San-Nan Yang

    2011-01-01

    Perinatal hypoxic-ischemic encephalopathy (HIE) is an important cause of brain injury in the newborn and can result in long-term devastating consequences. Perinatal hypoxia is a vital cause of long-term neurologic complications varying from mild behavioural deficits to severe seizure, mental retardation, and/or cerebral palsy in the newborn. In the mammalian developing brain, ongoing research into pathophysiological mechanism of neuronal injury and therapeutic strategy after perinatal hypoxia...

  5. Influence on the mouse immune system of chronic ingestion of {sup 137}Cs

    Energy Technology Data Exchange (ETDEWEB)

    Bertho, Jean-Marc; Faure, Marie-Cecile; Louiba, Sonia; Tourlonias, Elie; Stefani, Johanna; Siffert, Baptiste; Paquet, Francois; Dublineau, Isabelle, E-mail: Jean-marc.bertho@irsn.fr [IRSN, Laboratoire de Radiotoxicologie Experimentale, Fontenay aux Roses (France)

    2011-03-01

    The aim of this work was to determine the possible occurrence of damage to the immune system during the course of chronic ingestion of {sup 137}Cs. BALB/C mice were used, with {sup 137}Cs intake via drinking water at a concentration of 20 kBq l{sup -1}. Adults received {sup 137}Cs before mating and offspring were sacrificed at various ages between birth and 20 weeks. Phenotypic analysis of circulating blood cells and thymocytes did not show any significant modification of immune cell populations in animals ingesting {sup 137}Cs as compared with control animals, with the exception of a slight increase in Treg percentage at the age of 12 weeks. Functional tests, including proliferative response to mitogens such as phytohaemagglutinin, response to alloantigens in mixed lymphocyte reaction and immunoglobulin response to vaccine antigens such as tetanus toxin and keyhole limpet haemocyanin did not show any significant functional modification of the immune system in {sup 137}Cs-ingesting animals as compared with control animals. Overall, our results suggest that chronic ingestion of a low concentration of {sup 137}Cs in drinking water in the long term does not have any biologically relevant effect on the immune system.

  6. Chronic stress induced cognitive impairment in APP/PS-1 double transgenic mouse model of Alzheimer's disease

    Directory of Open Access Journals (Sweden)

    Bing HAN

    2015-08-01

    Full Text Available Objective  To observe the effect of chronic unpredictable mild stress (CUMS on the cognitive function and brain morphological changes in APP/PS-1 mice, one of the genetic mouse models of Alzheimer's disease (AD, and to investigate the possible role of environmental factors in genetic mouse model of AD. Methods  There were 22-week-old wild-type C57BL/6 male mice (control group, N = 15 and APP/PS-1 double transgenic male mice [N = 27: AD group (N = 13 and AD + CUMS group (N = 14] tested in this study. Morris water maze test was used to evaluate spatial learning and memory of the mice. Amyloid deposition in the hippocampus was determined by Congo red staining. The ultrastructure of neurons in hippocampal CA1 region was observed by transmission electron microscope (TEM.  Results  Compared with control group, AD + CUMS group had significantly longer fifth-day escape latency [(33.14 ± 14.37 s vs (21.22 ± 12.16 s; t = -2.701, P = 0.045], and significantly shortened time spent in platform quadrant [(9.74±1.35 s vs (15.02 ± 1.33 s; t = 2.639, P = 0.012] in Morris water maze test. Compared with AD group, the percentage of amyloid plaque area in hippocampal area was increased in AD + CUMS group [(0.59 ± 0.03% vs (0.04 ± 0.03%; t = -2.900, P = 0.005]. The ultrastructure of hippocampal neurons in AD group was slightly damaged: cellular membrane was intact; cell matrix was uniform; intracelluar lipofuscin could be seen; the structure of nucleus and nuclear membrane had no obvious changes; mild fusion of cristae and membrane was seen in mitochondria; Golgi apparatus was partially indistinct; endoplasmic reticulum was mildly expanded. The ultrastructure of hippocampal neurons in AD + CUMS group was obviously damaged, including blurred cell membrane, reduced low-density and high-density granules in cytoplasm, uneven cell matrix, reduced number of organelles, lipofuscin and autophagosome deposition, obvious condensation of chromatin distributing over

  7. Evaluation of skeletal and cardiac muscle function after chronic administration of thymosin beta-4 in the dystrophin deficient mouse.

    Directory of Open Access Journals (Sweden)

    Christopher F Spurney

    Full Text Available Thymosin beta-4 (Tbeta4 is a ubiquitous protein with many properties relating to cell proliferation and differentiation that promotes wound healing and modulates inflammatory mediators. We studied the effects of chronic administration of Tbeta4 on the skeletal and cardiac muscle of dystrophin deficient mdx mice, the mouse model of Duchenne muscular dystrophy. Female wild type (C57BL10/ScSnJ and mdx mice, 8-10 weeks old, were treated with 150 microg of Tbeta4 twice a week for 6 months. To promote muscle pathology, mice were exercised for 30 minutes twice a week. Skeletal and cardiac muscle function were assessed via grip strength and high frequency echocardiography. Localization of Tbeta4 and amount of fibrosis were quantified using immunohistochemistry and Gomori's tri-chrome staining, respectively. Mdx mice treated with Tbeta4 showed a significant increase in skeletal muscle regenerating fibers compared to untreated mdx mice. Tbeta4 stained exclusively in the regenerating fibers of mdx mice. Although untreated mdx mice had significantly decreased skeletal muscle strength compared to untreated wild type, there were no significant improvements in mdx mice after treatment. Systolic cardiac function, measured as percent shortening fraction, was decreased in untreated mdx mice compared to untreated wild type and there was no significant difference after treatment in mdx mice. Skeletal and cardiac muscle fibrosis were also significantly increased in untreated mdx mice compared to wild type, but there was no significant improvement in treated mdx mice. In exercised dystrophin deficient mice, chronic administration of Tbeta4 increased the number of regenerating fibers in skeletal muscle and could have a potential role in treatment of skeletal muscle disease in Duchenne muscular dystrophy.

  8. Chronic Contractile Dysfunction without Hypertrophy Does Not Provoke a Compensatory Transcriptional Response in Mouse Hearts.

    Directory of Open Access Journals (Sweden)

    Scot J Matkovich

    Full Text Available Diseased myocardium from humans and experimental animal models shows heightened expression and activity of a specific subtype of phospholipase C (PLC, the splice variant PLCβ1b. Previous studies from our group showed that increasing PLCβ1b expression in adult mouse hearts by viral transduction was sufficient to cause sustained contractile dysfunction of rapid onset, which was maintained indefinitely in the absence of other pathological changes in the myocardium. We hypothesized that impaired contractility alone would be sufficient to induce a compensatory transcriptional response. Unbiased, comprehensive mRNA-sequencing was performed on 6 biological replicates of rAAV6-treated blank, PLCβ1b and PLCβ1a (closely related but inactive splice variant hearts 8 weeks after injection, when reduced contractility was manifest in PLCβ1b hearts without evidence of induced hypertrophy. Expression of PLCβ1b resulted in expression changes in only 9 genes at FDR<0.1 when compared with control and these genes appeared unrelated to contractility. Importantly, PLCβ1a caused similar mild expression changes to PLCβ1b, despite a complete lack of effect of this isoform on cardiac contractility. We conclude that contractile depression caused by PLCβ1b activation is largely independent of changes in the transcriptome, and thus that lowered contractility is not sufficient in itself to provoke measurable transcriptomic alterations. In addition, our data stress the importance of a stringent control group to filter out transcriptional changes unrelated to cardiac function.

  9. Chronic Contractile Dysfunction without Hypertrophy Does Not Provoke a Compensatory Transcriptional Response in Mouse Hearts.

    Science.gov (United States)

    Matkovich, Scot J; Grubb, David R; McMullen, Julie R; Woodcock, Elizabeth A

    2016-01-01

    Diseased myocardium from humans and experimental animal models shows heightened expression and activity of a specific subtype of phospholipase C (PLC), the splice variant PLCβ1b. Previous studies from our group showed that increasing PLCβ1b expression in adult mouse hearts by viral transduction was sufficient to cause sustained contractile dysfunction of rapid onset, which was maintained indefinitely in the absence of other pathological changes in the myocardium. We hypothesized that impaired contractility alone would be sufficient to induce a compensatory transcriptional response. Unbiased, comprehensive mRNA-sequencing was performed on 6 biological replicates of rAAV6-treated blank, PLCβ1b and PLCβ1a (closely related but inactive splice variant) hearts 8 weeks after injection, when reduced contractility was manifest in PLCβ1b hearts without evidence of induced hypertrophy. Expression of PLCβ1b resulted in expression changes in only 9 genes at FDRcaused similar mild expression changes to PLCβ1b, despite a complete lack of effect of this isoform on cardiac contractility. We conclude that contractile depression caused by PLCβ1b activation is largely independent of changes in the transcriptome, and thus that lowered contractility is not sufficient in itself to provoke measurable transcriptomic alterations. In addition, our data stress the importance of a stringent control group to filter out transcriptional changes unrelated to cardiac function. PMID:27359099

  10. The role of polyamines in protein-dependent hypoxic tolerance of Drosophila

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    Vigne Paul

    2008-12-01

    Full Text Available Abstract Background Chronic hypoxia is a major component of ischemic diseases such as stroke or myocardial infarction. Drosophila is more tolerant to hypoxia than most mammalian species. It is considered as a useful model organism to identify new mechanisms of hypoxic tolerance. The hypoxic tolerance of flies has previously been reported to be enhanced by low protein diets. This study analyses the mechanisms involved. Results Feeding adult Drosophila on a yeast diet dramatically reduced their longevities under chronic hypoxic conditions (5% O2. Mean and maximum longevities became close to the values observed for starving flies. The action of dietary yeast was mimicked by a whole casein hydrolysate and by anyone of the 20 natural amino acids that compose proteins. It was mimicked by amino acid intermediates of the urea cycle such as L-citrulline and L-ornithine, and by polyamines (putrescine, spermidine and spermine. α-difluoromethylornithine, a specific inhibitor of ornithine decarboxylase, partially protected hypoxic flies from amino acid toxicity but not from polyamine toxicity. N1-guanyl-1,7 diaminoheptane, a specific inhibitor of eIF5A hypusination, partially relieved the toxicities of both amino acids and polyamines. Conclusion Dietary amino acids reduced the longevity of chronically hypoxic flies fed on a sucrose diet. Pharmacological evidence suggests that the synthesis of polyamines and the hypusination of eIF5A contributed to the life-shortening effect of dietary amino acids.

  11. Immunoendocrine interactions during chronic cysticercosis determine male mouse feminization: role of IL-6.

    Science.gov (United States)

    Morales-Montor, J; Baig, S; Mitchell, R; Deway, K; Hallal-Calleros, C; Damian, R T

    2001-10-15

    Taenia crassiceps cysticercosis results in an impressive feminization in male mice during chronic infection, characterized by increased serum estradiol levels 100 times their normal values, while those of testosterone and dihydrotestosterone are decreased by 85 and 95% respectively. Concomitantly, the levels of follicle-stimulating hormone and IL-6 are increased 70 and 90 times their normal values in the infected male mice. Since a specific Th1/Th2 shift of the immune response has been previously reported during the chronic infection, and this shift may be associated with the feminization process, we proposed that this shift is induced by immunoendocrine interactions during the disease, and this gives way to a change in the initial resistance to the infection in the male mice, which become as susceptible as female mice. To confirm this hypothesis, we depleted immune system activity in two different ways: total body irradiation and neonatal thymectomy. Our results show that when immune system activity is depleted using either strategy, the male mice do not feminize, and the levels of follicle-stimulating hormone and IL-6 are inhibited. Depletion of IL-6 using IL-6(-/-) knockout mice does not produce the feminization process stated above, while restitution of the IL-6(-/-) knockout, irradiated, and thymectomized mice with murine recombinant IL-6 restores the feminization process. Expression of the IL-6 gene was found only in the testes and spleen of infected animals. Our results illustrate the importance of immunoendocrine interactions during a parasitic disease and show a possible new mechanism of parasite establishment in an initially resistant host.

  12. The Enduring Hypoxic Response of Mycobacterium tuberculosis

    OpenAIRE

    Rustad, Tige R; Harrell, Maria. I.; Liao, Reiling; David R Sherman

    2008-01-01

    Background A significant body of evidence accumulated over the last century suggests a link between hypoxic microenvironments within the infected host and the latent phase of tuberculosis. Studies to test this correlation have identified the M. tuberculosis initial hypoxic response, controlled by the two-component response regulator DosR. The initial hypoxic response is completely blocked in a dosR deletion mutant. Methodology/Principal Findings We show here that a dosR deletion mutant enters...

  13. Chronic Myelogenous Leukemia Cells Contribute to the Stromal Myofibroblasts in Leukemic NOD/SCID Mouse In Vivo

    Directory of Open Access Journals (Sweden)

    Ryosuke Shirasaki

    2012-01-01

    Full Text Available We recently reported that chronic myelogenous leukemia (CML cells converted into myofibroblasts to create a microenvironment for proliferation of CML cells in vitro. To analyze a biological contribution of CML-derived myofibroblasts in vivo, we observed the characters of leukemic nonobese diabetes/severe combined immunodeficiency (NOD/SCID mouse. Bone marrow nonadherent mononuclear cells as well as human CD45-positive cells obtained from CML patients were injected to the irradiated NOD/SCID mice. When the chimeric BCR-ABL transcript was demonstrated in blood, human CML cells were detected in NOD/SCID murine bone marrow. And CML-derived myofibroblasts composed with the bone marrow-stroma, which produced significant amounts of human vascular endothelial growth factor A. When the parental CML cells were cultured with myofibroblasts separated from CML cell-engrafted NOD/SCID murine bone marrow, CML cells proliferated significantly. These observations indicate that CML cells make an adequate microenvironment for their own proliferation in vivo.

  14. Chronic Microdose Lithium Treatment Prevented Memory Loss and Neurohistopathological Changes in a Transgenic Mouse Model of Alzheimer's Disease.

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    Marielza Andrade Nunes

    Full Text Available The use of lithium is well established in bipolar disorders and the benefits are being demonstrated in neurodegenerative disorders. Recently, our group showed that treatment with microdose lithium stabilized the cognitive deficits observed in Alzheimer's disease (AD patients. In order to verify the lithium microdose potential in preventing the disease development, the aim of this work was to verify the effects of chronic treatment with microdose lithium given before and after the appearance of symptoms in a mouse model of a disease similar to AD. Transgenic mice (Cg-Tg(PDGFB-APPSwInd20Lms/2J and their non-transgenic litter mate genetic controls were treated with lithium carbonate (0.25mg/Kg/day in drinking water for 16 or 8 months starting at two and ten months of age, respectively [corrected]. Similar groups were treated with water. At the end of treatments, both lithium treated transgenic groups and non-transgenic mice showed no memory disruption, different from what was observed in the water treated transgenic group. Transgenic mice treated with lithium since two months of age showed decreased number of senile plaques, no neuronal loss in cortex and hippocampus and increased BDNF density in cortex, when compared to non-treated transgenic mice. It is suitable to conclude that these data support the use of microdose lithium in the prevention and treatment of Alzheimer's disease, once the neurohistopathological characteristics of the disease were modified and the memory of transgenic animals was maintained.

  15. Chronic Microdose Lithium Treatment Prevented Memory Loss and Neurohistopathological Changes in a Transgenic Mouse Model of Alzheimer's Disease.

    Science.gov (United States)

    Nunes, Marielza Andrade; Schöwe, Natalia Mendes; Monteiro-Silva, Karla Cristina; Baraldi-Tornisielo, Ticiana; Souza, Suzzanna Ingryd Gonçalves; Balthazar, Janaina; Albuquerque, Marilia Silva; Caetano, Ariadiny Lima; Viel, Tania Araujo; Buck, Hudson Sousa

    2015-01-01

    The use of lithium is well established in bipolar disorders and the benefits are being demonstrated in neurodegenerative disorders. Recently, our group showed that treatment with microdose lithium stabilized the cognitive deficits observed in Alzheimer's disease (AD) patients. In order to verify the lithium microdose potential in preventing the disease development, the aim of this work was to verify the effects of chronic treatment with microdose lithium given before and after the appearance of symptoms in a mouse model of a disease similar to AD. Transgenic mice (Cg-Tg(PDGFB-APPSwInd)20Lms/2J) and their non-transgenic litter mate genetic controls were treated with lithium carbonate (0.25mg/Kg/day in drinking water) for 16 or 8 months starting at two and ten months of age, respectively [corrected]. Similar groups were treated with water. At the end of treatments, both lithium treated transgenic groups and non-transgenic mice showed no memory disruption, different from what was observed in the water treated transgenic group. Transgenic mice treated with lithium since two months of age showed decreased number of senile plaques, no neuronal loss in cortex and hippocampus and increased BDNF density in cortex, when compared to non-treated transgenic mice. It is suitable to conclude that these data support the use of microdose lithium in the prevention and treatment of Alzheimer's disease, once the neurohistopathological characteristics of the disease were modified and the memory of transgenic animals was maintained. PMID:26605788

  16. Metabolomic identification of biochemical changes induced by fluoxetine and imipramine in a chronic mild stress mouse model of depression

    Science.gov (United States)

    Zhao, Jing; Jung, Yang-Hee; Jang, Choon-Gon; Chun, Kwang-Hoon; Kwon, Sung Won; Lee, Jeongmi

    2015-03-01

    Metabolomics was applied to a C57BL/6N mouse model of chronic unpredictable mild stress (CMS). Such mice were treated with two antidepressants from different categories: fluoxetine and imipramine. Metabolic profiling of the hippocampus was performed using gas chromatography-mass spectrometry analysis on samples prepared under optimized conditions, followed by principal component analysis, partial least squares-discriminant analysis, and pair-wise orthogonal projections to latent structures discriminant analyses. Body weight measurement and behavior tests including an open field test and the forced swimming test were completed with the mice as a measure of the phenotypes of depression and antidepressive effects. As a result, 23 metabolites that had been differentially expressed among the control, CMS, and antidepressant-treated groups demonstrated that amino acid metabolism, energy metabolism, adenosine receptors, and neurotransmitters are commonly perturbed by drug treatment. Potential predictive markers for treatment effect were identified: myo-inositol for fluoxetine and lysine and oleic acid for imipramine. Collectively, the current study provides insights into the molecular mechanisms of the antidepressant effects of two widely used medications.

  17. Chronic Pharmacological mGluR5 Inhibition Prevents Cognitive Impairment and Reduces Pathogenesis in an Alzheimer Disease Mouse Model.

    Science.gov (United States)

    Hamilton, Alison; Vasefi, Maryam; Vander Tuin, Cheryl; McQuaid, Robyn J; Anisman, Hymie; Ferguson, Stephen S G

    2016-05-31

    Beta-amyloid (Aβ) oligomers contribute to the pathophysiology of Alzheimer disease (AD), and metabotropic glutamate receptor 5 (mGluR5) has been shown to act as a receptor for both Aβ oligomers and cellular prion proteins. Furthermore, the genetic deletion of mGluR5 in an APPswe/PS1ΔE9 mouse model of AD improves cognitive function and reduces Aβ plaques and Aβ oligomer concentrations. Here, we show that chronic administration of the orally bioavailable mGluR5-selective negative allosteric modulator CTEP, which is similar in structure, potency, and selectivity to Basimglurant (RO4917523), which is currently in phase II clinical development for major depressive disorder and fragile X syndrome, reverses cognitive decline in APPswe/PS1ΔE9 mice and reduces Aβ plaque deposition and soluble Aβ oligomer concentrations in both APPswe/PS1ΔE9 and 3xTg-AD male mice. These findings suggest that CTEP or its analogue Basimglutant might potentially be an effective therapeutic for the treatment of AD patients. PMID:27210751

  18. The mouse as a model for understanding chronic diseases of aging: the histopathologic basis of aging in inbred mice

    Directory of Open Access Journals (Sweden)

    David Harrison

    2011-06-01

    Full Text Available Inbred mice provide a unique tool to study aging populations because of the genetic homogeneity within an inbred strain, their short life span, and the tools for analysis which are available. A large-scale longitudinal and cross-sectional aging study was conducted on 30 inbred strains to determine, using histopathology, the type and diversity of diseases mice develop as they age. These data provide tools that when linked with modern in silico genetic mapping tools, can begin to unravel the complex genetics of many of the common chronic diseases associated with aging in humans and other mammals. In addition, novel disease models were discovered in some strains, such as rhabdomyosarcoma in old A/J mice, to diseases affecting many but not all strains including pseudoxanthoma elasticum, pulmonary adenoma, alopecia areata, and many others. This extensive data set is now available online and provides a useful tool to help better understand strain-specific background diseases that can complicate interpretation of genetically engineered mice and other manipulatable mouse studies that utilize these strains.

  19. Role of bile acids, prostaglandins and COX inhibitors in chronic esophagitis in a mouse model

    Institute of Scientific and Technical Information of China (English)

    C Poplawski; D Sosnowski; A Szaflarska-Poplawska; J Sarosiek; R McCallum; Z Bartuzi

    2006-01-01

    33 %). In HCl/P/BA/INDO group the esophagitis surface was larger than that in not treated group (33%). In HCL/P group the surface of esophagus with ulceration was significantly larger (10-fold) than that in HCl/P/BA group. The PGE2 concentration was significantly higher in HCl/P group than in HCl/P/BA group.The PGE2 concentration in lower part of esophagus was also significantly higher in middle than those in HCl and HCl/P/BA groups. In upper part of esophagus the PGE2 concentration was significantly higher in HCl/P/BA group than that in group treated with indometacine (46%). We also observed higher PGE2 concentration in middle part of esophagus in HCl/P/BA group than those in group treated with indometacine and in group treated with indometacin and NS-398 (by 52% and 43% respectively).CONCLUSION: Pepsin is the pivotal factor in the development of chronic esophageal injury. Bile acids diminish chronic esophageal injury induced by HCl/P, indicating its potential negative impact on pepsin proteolytic potential,pivotal for mucosal injury in low pH. The role of selective COX inhibitors is still unclear, and needs more investigations. This novel chronic experimental esophagitis is an excellent model for further study on the role of cytokines in genetically modified animals.

  20. Chronic antidiabetic sulfonylureas in vivo: reversible effects on mouse pancreatic beta-cells.

    Directory of Open Access Journals (Sweden)

    Maria Sara Remedi

    2008-10-01

    Full Text Available BACKGROUND: Pancreatic beta-cell ATP-sensitive potassium (K ATP channels are critical links between nutrient metabolism and insulin secretion. In humans, reduced or absent beta-cell K ATP channel activity resulting from loss-of-function K ATP mutations induces insulin hypersecretion. Mice with reduced K ATP channel activity also demonstrate hyperinsulinism, but mice with complete loss of K ATP channels (K ATP knockout mice show an unexpected insulin undersecretory phenotype. Therefore we have proposed an "inverse U" hypothesis to explain the response to enhanced excitability, in which excessive hyperexcitability drives beta-cells to insulin secretory failure without cell death. Many patients with type 2 diabetes treated with antidiabetic sulfonylureas (which inhibit K ATP activity and thereby enhance insulin secretion show long-term insulin secretory failure, which we further suggest might reflect a similar progression. METHODS AND FINDINGS: To test the above hypotheses, and to mechanistically investigate the consequences of prolonged hyperexcitability in vivo, we used a novel approach of implanting mice with slow-release sulfonylurea (glibenclamide pellets, to chronically inhibit beta-cell K ATP channels. Glibenclamide-implanted wild-type mice became progressively and consistently diabetic, with significantly (p < 0.05 reduced insulin secretion in response to glucose. After 1 wk of treatment, these mice were as glucose intolerant as adult K ATP knockout mice, and reduction of secretory capacity in freshly isolated islets from implanted animals was as significant (p < 0.05 as those from K ATP knockout animals. However, secretory capacity was fully restored in islets from sulfonylurea-treated mice within hours of drug washout and in vivo within 1 mo after glibenclamide treatment was terminated. Pancreatic immunostaining showed normal islet size and alpha-/beta-cell distribution within the islet, and TUNEL staining showed no evidence of apoptosis

  1. Complement activation and expression during chronic relapsing experimental autoimmune encephalomyelitis in the Biozzi ABH mouse.

    Science.gov (United States)

    Ramaglia, V; Jackson, S J; Hughes, T R; Neal, J W; Baker, D; Morgan, B P

    2015-06-01

    Chronic relapsing experimental autoimmune encephalomyelitis (crEAE) in mice recapitulates many of the clinical and histopathological features of human multiple sclerosis (MS), making it a preferred model for the disease. In both, adaptive immunity and anti-myelin T cells responses are thought to be important, while in MS a role for innate immunity and complement has emerged. Here we sought to test whether complement is activated in crEAE and important for disease. Disease was induced in Biozzi ABH mice that were terminated at different stages of the disease to assess complement activation and local complement expression in the central nervous system. Complement activation products were abundant in all spinal cord areas examined in acute disease during relapse and in the progressive phase, but were absent in early disease remission, despite significant residual clinical disease. Local expression of C1q and C3 was increased at all stages of disease, while C9 expression was increased only in acute disease; expression of the complement regulators CD55, complement receptor 1-related gene/protein y (Crry) and CD59a was reduced at all stages of the disease compared to naive controls. These data show that complement is activated in the central nervous system in the model and suggest that it is a suitable candidate for exploring whether anti-complement agents might be of benefit in MS.

  2. Detection of hypoxic cells in murine tumors using the comet assay. Comparison with a conventional radiobiological assay

    International Nuclear Information System (INIS)

    The comet (single-cell electrophoresis) assay has been developed as a method for measuring DNA damage in single cells after irradiation. We have developed our own methods and image analysis system for the comet assay to identify hypoxic fractions. In vitro, we tested our system using a cultured tumor cell line (SCCVII). In vivo, we compared the hypoxic fractions detected by this assay with those determined by the in vivo-in vitro clonogenic assay using two rodent tumors (SCCVII/C3H, EMT6/KU/balb/c), which exhibit different types of hypoxia: acute and chronic. In vitro, our method could differentiate hypoxic cells from oxic cells, using the parameter of tail moment. In vivo, there were good correlations between the hypoxic fractions determined by the comet assay and by the clonogenic assay, in SCCVII/C3H (r=0.85) and in EMT6/KU/balb/c (r=0.75) tumors. By comparison of the two methods in chronically hypoxic and acutely hypoxic tumors, we further confirmed that the comet assay is clinically useful for estimating hypoxic fractions of solid tumors. (author)

  3. Perinatal Hypoxic-Ischemic Encephalopathy

    Directory of Open Access Journals (Sweden)

    Ming-Chi Lai

    2011-01-01

    Full Text Available Perinatal hypoxic-ischemic encephalopathy (HIE is an important cause of brain injury in the newborn and can result in long-term devastating consequences. Perinatal hypoxia is a vital cause of long-term neurologic complications varying from mild behavioural deficits to severe seizure, mental retardation, and/or cerebral palsy in the newborn. In the mammalian developing brain, ongoing research into pathophysiological mechanism of neuronal injury and therapeutic strategy after perinatal hypoxia is still limited. With the advent of promising therapy of hypothermia in HIE, this paper reviews the pathophysiology of HIE and the future potential neuroprotective strategies for clinical potential for hypoxia sufferers.

  4. Hypoxic pulmonary vasodilation: a paradigm shift with a hydrogen sulfide mechanism

    OpenAIRE

    Olson, Kenneth R.; Whitfield, Nathan L.; Bearden, Shawn E.; St. Leger, Judy; Nilson, Erika; Gao, Yan; Madden, Jane A.

    2009-01-01

    Hypoxic pulmonary vasoconstriction (HVC), an intrinsic and assumed ubiquitous response of mammalian pulmonary blood vessels, matches regional ventilation to perfusion via an unknown O2-sensing mechanism. Global pulmonary hypoxia experienced by individuals suffering from chronic obstructive pulmonary disease or numerous hypoventilation syndromes, including sleep apnea, often produces maladaptive pulmonary hypertension, but pulmonary hypertension is not observed in diving mammals, where profoun...

  5. Neurodegeneration severity can be predicted from early microglia alterations monitored in vivo in a mouse model of chronic glaucoma

    Directory of Open Access Journals (Sweden)

    Alejandra Bosco

    2015-05-01

    Full Text Available Microglia serve key homeostatic roles, and respond to neuronal perturbation and decline with a high spatiotemporal resolution. The course of all chronic CNS pathologies is thus paralleled by local microgliosis and microglia activation, which begin at early stages of the disease. However, the possibility of using live monitoring of microglia during early disease progression to predict the severity of neurodegeneration has not been explored. Because the retina allows live tracking of fluorescent microglia in their intact niche, here we investigated their early changes in relation to later optic nerve neurodegeneration. To achieve this, we used the DBA/2J mouse model of inherited glaucoma, which develops progressive retinal ganglion cell degeneration of variable severity during aging, and represents a useful model to study pathogenic mechanisms of retinal ganglion cell decline that are similar to those in human glaucoma. We imaged CX3CR1+/GFP microglial cells in vivo at ages ranging from 1 to 5 months by confocal scanning laser ophthalmoscopy (cSLO and quantified cell density and morphological activation. We detected early microgliosis at the optic nerve head (ONH, where axonopathy first manifests, and could track attenuation of this microgliosis induced by minocycline. We also observed heterogeneous and dynamic patterns of early microglia activation in the retina. When the same animals were aged and analyzed for the severity of optic nerve pathology at 10 months of age, we found a strong correlation with the levels of ONH microgliosis at 3 to 4 months. Our findings indicate that live imaging and monitoring the time course and levels of early retinal microgliosis and microglia activation in glaucoma could serve as indicators of future neurodegeneration severity.

  6. CFTR and sphingolipids mediate hypoxic pulmonary vasoconstriction.

    Science.gov (United States)

    Tabeling, Christoph; Yu, Hanpo; Wang, Liming; Ranke, Hannes; Goldenberg, Neil M; Zabini, Diana; Noe, Elena; Krauszman, Adrienn; Gutbier, Birgitt; Yin, Jun; Schaefer, Michael; Arenz, Christoph; Hocke, Andreas C; Suttorp, Norbert; Proia, Richard L; Witzenrath, Martin; Kuebler, Wolfgang M

    2015-03-31

    Hypoxic pulmonary vasoconstriction (HPV) optimizes pulmonary ventilation-perfusion matching in regional hypoxia, but promotes pulmonary hypertension in global hypoxia. Ventilation-perfusion mismatch is a major cause of hypoxemia in cystic fibrosis. We hypothesized that cystic fibrosis transmembrane conductance regulator (CFTR) may be critical in HPV, potentially by modulating the response to sphingolipids as mediators of HPV. HPV and ventilation-perfusion mismatch were analyzed in isolated mouse lungs or in vivo. Ca(2+) mobilization and transient receptor potential canonical 6 (TRPC6) translocation were studied in human pulmonary (PASMCs) or coronary (CASMCs) artery smooth muscle cells. CFTR inhibition or deficiency diminished HPV and aggravated ventilation-perfusion mismatch. In PASMCs, hypoxia caused CFTR to interact with TRPC6, whereas CFTR inhibition attenuated hypoxia-induced TRPC6 translocation to caveolae and Ca(2+) mobilization. Ca(2+) mobilization by sphingosine-1-phosphate (S1P) was also attenuated by CFTR inhibition in PASMCs, but amplified in CASMCs. Inhibition of neutral sphingomyelinase (nSMase) blocked HPV, whereas exogenous nSMase caused TRPC6 translocation and vasoconstriction that were blocked by CFTR inhibition. nSMase- and hypoxia-induced vasoconstriction, yet not TRPC6 translocation, were blocked by inhibition or deficiency of sphingosine kinase 1 (SphK1) or antagonism of S1P receptors 2 and 4 (S1P2/4). S1P and nSMase had synergistic effects on pulmonary vasoconstriction that involved TRPC6, phospholipase C, and rho kinase. Our findings demonstrate a central role of CFTR and sphingolipids in HPV. Upon hypoxia, nSMase triggers TRPC6 translocation, which requires its interaction with CFTR. Concomitant SphK1-dependent formation of S1P and activation of S1P2/4 result in phospholipase C-mediated TRPC6 and rho kinase activation, which conjointly trigger vasoconstriction. PMID:25829545

  7. Cardiac biomarkers in neonatal hypoxic ischaemia.

    LENUS (Irish Health Repository)

    Sweetman, D

    2012-04-01

    Following a perinatal hypoxic-ischaemic insult, term infants commonly develop cardiovascular dysfunction. Troponin-T, troponin-I and brain natriuretic peptide are sensitive indicators of myocardial compromise. The long-term effects of cardiovascular dysfunction on neurodevelopmental outcome following perinatal hypoxic ischaemia remain controversial. Follow-up studies are warranted to ensure optimal cardiac function in adulthood. CONCLUSION: Cardiac biomarkers may improve the diagnosis of myocardial injury, help guide management, estimate mortality risk and may also aid in longterm neurodevelopmental outcome prediction following neonatal hypoxic-ischaemia.

  8. Chronic Anatabine Treatment Reduces Alzheimer's Disease (AD-Like Pathology and Improves Socio-Behavioral Deficits in a Transgenic Mouse Model of AD.

    Directory of Open Access Journals (Sweden)

    Megha Verma

    Full Text Available Anatabine is a minor tobacco alkaloid, which is also found in plants of the Solanaceae family and displays a chemical structure similarity with nicotine. We have shown previously that anatabine displays some anti-inflammatory properties and reduces microgliosis and tau phosphorylation in a pure mouse model of tauopathy. We therefore investigated the effects of a chronic oral treatment with anatabine in a transgenic mouse model (Tg PS1/APPswe of Alzheimer's disease (AD which displays pathological Aβ deposits, neuroinflammation and behavioral deficits. In the elevated plus maze, Tg PS1/APPswe mice exhibited hyperactivity and disinhibition compared to wild-type mice. Six and a half months of chronic oral anatabine treatment, suppressed hyperactivity and disinhibition in Tg PS1/APPswe mice compared to Tg PS1/APPswe receiving regular drinking water. Tg PS1/APPswe mice also elicited profound social interaction and social memory deficits, which were both alleviated by the anatabine treatment. We found that anatabine reduces the activation of STAT3 and NFκB in the vicinity of Aβ deposits in Tg PS1/APPswe mice resulting in a reduction of the expression of some of their target genes including Bace1, iNOS and Cox-2. In addition, a significant reduction in microgliosis and pathological deposition of Aβ was observed in the brain of Tg PS1/APPswe mice treated with anatabine. This is the first study to investigate the impact of chronic anatabine treatment on AD-like pathology and behavior in a transgenic mouse model of AD. Overall, our data show that anatabine reduces β-amyloidosis, neuroinflammation and alleviates some behavioral deficits in Tg PS1/APPswe, supporting further exploration of anatabine as a possible disease modifying agent for the treatment of AD.

  9. Impaired Bronchoprotection Is Not Induced by Increased Smooth Muscle Mass in Chronic Treatment In Vivo with Formoterol in Asthmatic Mouse Model

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    W Luo

    2014-09-01

    Full Text Available Objective: Inhaling β2-adrenoceptor agonist is first-line asthma treatment, which is used for both acute relief and prevention of bronchoconstriction. However, chronic use of β-agonists results in impaired bronchoprotection and increasing occurrences of severe asthma exacerbation, even death in clinical practice. The mechanism of β-adrenoceptor hyposensitivity has not been thoroughly elucidated thus far. Bronchial smooth muscle contraction induces airway narrowing and also mediates airway inflammation. Moreover, bronchial smooth muscle mass significantly increases in asthmatics. We aimed to establish an asthmatic model that demonstrated that formoterol induced impaired bronchoprotection and to see whether increased smooth muscle mass played a role in it. Methods: We combined routine allergen challenging (seven weeks with repeated application of formoterol, formoterol plus budesonide or physiological saline in allergen-sensitized BALB/c mouse. The bronchoprotection mediated by β-agonist was measured in five consecutive weeks. Smooth muscle mass was shown by morphometric analysis, and α-actin expression was detected by western blot. Results: The trend of bronchoprotection was wavy in drug interventional groups, which initially increased and then decreased. Chronic treatment with formoterol significantly impaired bronchoprotection. According to the morphometric analysis and α-actin expression, no significant difference was detected in smooth muscle mass in all groups. Conclusion: This experiment successfully established that a chronic asthmatic mouse model, which manifested typical features of asthmatic patients, with chronic use of formoterol, results in a loss of bronchoprotection. No significant difference was detected in smooth muscle mass in all groups, which implied some subcellular signalling changes may be the key points.

  10. Adapting radiotherapy to hypoxic tumours

    Energy Technology Data Exchange (ETDEWEB)

    Malinen, Eirik [Department of Radiation Biology, Institute for Cancer Research, Norwegian Radium Hospital, Oslo (Norway); Soevik, Aste [Department of Medical Physics and Technology, Norwegian Radium Hospital, Oslo (Norway); Hristov, Dimitre [Siemens Medical Solutions Inc., Concord, CA (United States); Bruland, Oeyvind S [Department of Oncology, Norwegian Radium Hospital, Oslo (Norway); Olsen, Dag Rune [Department of Radiation Biology, Institute for Cancer Research, Norwegian Radium Hospital, Oslo (Norway)

    2006-10-07

    In the current work, the concepts of biologically adapted radiotherapy of hypoxic tumours in a framework encompassing functional tumour imaging, tumour control predictions, inverse treatment planning and intensity modulated radiotherapy (IMRT) were presented. Dynamic contrast enhanced magnetic resonance imaging (DCEMRI) of a spontaneous sarcoma in the nasal region of a dog was employed. The tracer concentration in the tumour was assumed related to the oxygen tension and compared to Eppendorf histograph measurements. Based on the pO{sub 2}-related images derived from the MR analysis, the tumour was divided into four compartments by a segmentation procedure. DICOM structure sets for IMRT planning could be derived thereof. In order to display the possible advantages of non-uniform tumour doses, dose redistribution among the four tumour compartments was introduced. The dose redistribution was constrained by keeping the average dose to the tumour equal to a conventional target dose. The compartmental doses yielding optimum tumour control probability (TCP) were used as input in an inverse planning system, where the planning basis was the pO{sub 2}-related tumour images from the MR analysis. Uniform (conventional) and non-uniform IMRT plans were scored both physically and biologically. The consequences of random and systematic errors in the compartmental images were evaluated. The normalized frequency distributions of the tracer concentration and the pO{sub 2} Eppendorf measurements were not significantly different. 28% of the tumour had, according to the MR analysis, pO{sub 2} values of less than 5 mm Hg. The optimum TCP following a non-uniform dose prescription was about four times higher than that following a uniform dose prescription. The non-uniform IMRT dose distribution resulting from the inverse planning gave a three times higher TCP than that of the uniform distribution. The TCP and the dose-based plan quality depended on IMRT parameters defined in the inverse

  11. Chronic ethanol intake modifies pyrrolidon carboxypeptidase activity in mouse frontal cortex synaptosomes under resting and K+ -stimulated conditions: role of calcium.

    Science.gov (United States)

    Mayas, María Dolores; Ramírez-Expósito, María Jesús; García-López, María Jesús; Carrera, María Pilar; Martínez-Martos, José Manuel

    2008-07-01

    Pyrrolidon carboxypeptidase (Pcp) is an omega peptidase that removes pyroglutamyl N-terminal residues of peptides such as thyrotrophin-releasing hormone (TRH), which is one of the neuropeptides that has been localized into many areas of the brain and acts as an endogenous neuromodulator of several parameters related to ethanol (EtOH) consumption. In this study, we analysed the effects of chronic EtOH intake on Pcp activity on mouse frontal cortex synaptosomes and their corresponding supernatant under basal and K+ -stimulated conditions, in presence and absence of calcium (Ca2+) to know the regulation of Pcp on TRH. In basal conditions, chronic EtOH intake significantly decreased synaptosomes Pcp activity but only in absence of Ca2+. However, supernatant Pcp activity is also decreased in presence and absence of calcium. Under K+-stimulated conditions, chronic EtOH intake decreased synaptosomes Pcp activity but only in absence of Ca2+, whereas supernatant Pcp activity was significantly decreased only in presence of Ca2+. The general inhibitory effect of chronic EtOH intake on Pcp activity suggests an inhibition of TRH metabolism and an enhancement of TRH neurotransmitter/neuromodulator functions, which could be related to putative processes of tolerance to EtOH in which TRH has been involved. Our data may also indicate that active peptides and their degrading peptidases are released together to the synaptic cleft to regulate the neurotransmitter/neuromodulator functions of these peptides, through a Ca2+ -dependent mechanism.

  12. Clinical observation of cytidine disodium triphosphate combined with mouse nerve growth factor in treatment of neonatal hypoxic ischemic encephalopathy%三磷酸胞苷二钠联合鼠神经生长因子治疗新生儿缺氧缺血性脑病的疗效观察

    Institute of Scientific and Technical Information of China (English)

    丁玉红; 闫俊梅; 闫静

    2015-01-01

    hypoxic ischemic encephalopathy.Methods Patients (80 cases) with hypoxic ischemic encephalopathy in Department of Neonatology of Xuzhou Maternity and Child Health Hospital from January 2013 to January 2014 were randomly divided into control and treatment groups, and each group had 40 cases. The patients in control group were imadministered with Mouse Nerve Growth Factor for injection 6 h after birth on the basis of foundation treatment, 30μg/time, once daily. The patients in treatment group were ivadministered with Cytidine Disodium Triphosphate for injection on the basis of control group, 100 mg/time added into 5% glucose injection 30 mL, once daily. Children with moderate were treated for 14 d, and children with severe were treated for 21 d. After treatment, the efficacy was evaluated, and symptoms and signs improved time, NBNA scores, and CDCC test results in two groups were compared.Results After treatment, the efficacies in the control and treatment groups were 72.5% and 92.5%, respectively, and there were differences between two groups (P < 0.05). After treatment, consciousness disturbance recovery time, seizures stop time, primitive reflex normal time, and muscle tension normal time in the treatment group were shorter than those in the control group, and there were differences between two groups (P < 0.05). After treatment, behavior ability score, passive muscle tension score, general assessment score and total score in two groups were significantly increased, and active muscle tension score and primitive reflex score in the treatment group were significantly increased, and the difference was statistically significant in the same group (P < 0.05). These observational indexes in the treatment group were better than those in the control group, withsignificant difference between two groups (P < 0.05). After birth of 6 and 12 months, MDI and PDI in treatment group were higher than those in the control group, with significant difference between two groups (P < 0

  13. Early onset of hypersynchronous network activity and expression of a marker of chronic seizures in the Tg2576 mouse model of Alzheimer's disease.

    Directory of Open Access Journals (Sweden)

    Charlotte Bezzina

    Full Text Available Cortical and hippocampal hypersynchrony of neuronal networks seems to be an early event in Alzheimer's disease pathogenesis. Many mouse models of the disease also present neuronal network hypersynchrony, as evidenced by higher susceptibility to pharmacologically-induced seizures, electroencephalographic seizures accompanied by spontaneous interictal spikes and expression of markers of chronic seizures such as neuropeptide Y ectopic expression in mossy fibers. This network hypersynchrony is thought to contribute to memory deficits, but whether it precedes the onset of memory deficits or not in mouse models remains unknown. The earliest memory impairments in the Tg2576 mouse model of Alzheimer's disease have been observed at 3 months of age. We thus assessed network hypersynchrony in Tg2576 and non-transgenic male mice at 1.5, 3 and 6 months of age. As soon as 1.5 months of age, Tg2576 mice presented higher seizure susceptibility to systemic injection of a GABAA receptor antagonist. They also displayed spontaneous interictal spikes on EEG recordings. Some Tg2576 mice presented hippocampal ectopic expression of neuropeptide Y which incidence seems to increase with age among the Tg2576 population. Our data reveal that network hypersynchrony appears very early in Tg2576 mice, before any demonstrated memory impairments.

  14. The Functional Study of a Chinese Herbal Compounded Antidepressant Medicine--Jie Yu Chu Fan Capsule on Chronic Unpredictable Mild Stress Mouse Model.

    Directory of Open Access Journals (Sweden)

    Lingling Ding

    Full Text Available Jie Yu Chu Fan capsule (JYCF is a new compounded Chinese herbal medicine for the treatment of depression. The present study was designed to explore the antidepressant effects and the possible mechanisms of JYCF by using chronic unpredictable mild stress (CUMS mouse model and comparing results to that of fluoxetine. Behavioral tests including an open field test, sucrose preference test and forced swim test were performed to evaluate the antidepressant effects of JYCF. The concentrations of monoamine neurotransmitters and metabolic products including norepinephrine (NE, 5-hydroxytryptamine (5-HT, dopamine (DA, 5-hydroxyindoleacetic acid (5-HIAA, homovanillic acid (HVA and 3,4-dihydroxyphenylacetic acid (DOPAC in the cerebral cortex and hippocampus of mice were determined by means of high performance liquid chromatography with electrochemical detection (HPLC-EC. The results show that a successful mouse CUMS model was established through 5 weeks of continuous unpredictable stimulation, as indicated by the significant decrease in sucrose preference and locomotor activity and increase in immobility time in the forced swim test. Chronic treatment of JYCF (1.25, 2.5 and 5 g/kg and fluoxetine (20 mg/kg significantly reversed the CUMS-induced behavioral abnormalities. JYCF (1.25, 2.5 and 5 g/kg significantly increased NE in CUMS mouse prefrontal cortex (P < 0.01, P < 0.01, P < 0.05 respectively and 5-HT in hippocampus (P < 0.05. In summary, our findings suggest that JYCF exerts comparable antidepressant-like effects to that of fluoxetine in CUMS mice. Besides, the antidepressant-like effect of JYCF is mediated by the increase of monoaminergic transmitters including 5-HT and NE.

  15. Chronic GluN2B antagonism disrupts behavior in wild-type mice without protecting against synapse loss or memory impairment in Alzheimer's disease mouse models.

    Science.gov (United States)

    Hanson, Jesse E; Meilandt, William J; Gogineni, Alvin; Reynen, Paul; Herrington, James; Weimer, Robby M; Scearce-Levie, Kimberly; Zhou, Qiang

    2014-06-11

    Extensive evidence implicates GluN2B-containing NMDA receptors (GluN2B-NMDARs) in excitotoxic-insult-induced neurodegeneration and amyloid β (Aβ)-induced synaptic dysfunction. Therefore, inhibiting GluN2B-NMDARs would appear to be a potential therapeutic strategy to provide neuroprotection and improve cognitive function in Alzheimer's disease (AD). However, there are no reports of long-term in vivo treatment of AD mouse models with GluN2B antagonists. We used piperidine18 (Pip18), a potent and selective GluN2B-NMDAR antagonist with favorable pharmacokinetic properties, for long-term dosing in AD mouse models. Reduced freezing behavior in Tg2576 mice during fear conditioning was partially reversed after subchronic (17 d) Pip18 treatment. However, analysis of freezing behavior in different contexts indicated that this increased freezing likely involves elevated anxiety or excessive memory generalization in both nontransgenic (NTG) and Tg2576 mice. In PS2APP mice chronically fed with medicated food containing Pip18 for 4 months, spatial learning and memory deficits were not rescued, plaque-associated spine loss was not affected, and synaptic function was not altered. At the same time, altered open field activity consistent with increased anxiety and degraded performance in an active avoidance task were observed in NTG after chronic treatment. These results indicate that long-term treatment with a GluN2B-NMDAR antagonist does not provide a disease-modifying benefit and could cause cognitive liabilities rather than symptomatic benefit in AD mouse models. Therefore, these results challenge the expectation of the therapeutic potential for GluN2B-NMDAR antagonists in AD.

  16. In Vivo Acute on Chronic Ethanol Effects in Liver: A Mouse Model Exhibiting Exacerbated Injury, Altered Metabolic and Epigenetic Responses.

    Science.gov (United States)

    Shukla, Shivendra D; Aroor, Annayya R; Restrepo, Ricardo; Kharbanda, Kusum K; Ibdah, Jamal A

    2015-11-20

    Chronic alcoholics who also binge drink (i.e., acute on chronic) are prone to an exacerbated liver injury but its mechanism is not understood. We therefore investigated the in vivo effects of chronic and binge ethanol ingestion and compared to chronic ethanol followed by three repeat binge ethanol on the liver of male C57/BL6 mice fed ethanol in liquid diet (4%) for four weeks followed by binge ethanol (intragastric administration, 3.5 g/kg body weight, three doses, 12h apart). Chronic followed by binge ethanol exacerbated fat accumulation, necrosis, decrease in hepatic SAM and SAM:SAH ratio, increase in adenosine levels, and elevated CYP2E1 levels. Histone H3 lysine acetylation (H3AcK9), dually modified phosphoacetylated histone H3 (H3AcK9/PS10), and phosphorylated H2AX increased after binge whereas phosphorylation of histone H3 ser 10 (H3S10) and H3 ser 28 (H3S28) increased after chronic ethanol-binge. Histone H3 lysine 4 and 9 dimethylation increased with a marked dimethylation in H3K9 in chronic ethanol binge group. Trimethylated histone H3 levels did not change. Nuclear levels of histone acetyl transferase GCN5 and histone deacetylase HDAC3 were elevated whereas phospho-CREB decreased in a distinctive manner. Taken together, acute on chronic ethanol ingestion caused amplification of liver injury and elicited characteristic profiles of histone modifications, metabolic alterations, and changes in nuclear protein levels. These findings demonstrate that chronic ethanol exposure renders liver more susceptible to repeat acute/binge ethanol induced acceleration of alcoholic liver disease.

  17. Chronic 5-HT4 receptor agonist treatment restores learning and memory deficits in a neuroendocrine mouse model of anxiety/depression.

    Science.gov (United States)

    Darcet, Flavie; Gardier, Alain M; David, Denis J; Guilloux, Jean-Philippe

    2016-03-11

    Cognitive disturbances are often reported as serious invalidating symptoms in patients suffering from major depression disorders (MDD) and are not fully corrected by classical monoaminergic antidepressant drugs. If the role of 5-HT4 receptor agonists as cognitive enhancers is well established in naïve animals or in animal models of cognitive impairment, their cognitive effects in the context of stress need to be examined. Using a mouse model of anxiety/depression (CORT model), we reported that a chronic 5-HT4 agonist treatment (RS67333, 1.5mg/kg/day) restored chronic corticosterone-induced cognitive deficits, including episodic-like, associative and spatial learning and memory impairments. On the contrary, a chronic monoaminergic antidepressant drug treatment with fluoxetine (18mg/kg/day) only partially restored spatial learning and memory deficits and had no effect in the associative/contextual task. These results suggest differential mechanisms underlying cognitive effects of these drugs. Finally, the present study highlights 5-HT4 receptor stimulation as a promising therapeutic mechanism to alleviate cognitive symptoms related to MDD. PMID:26850572

  18. Overendocytosis of gold nanoparticles increases autophagy and apoptosis in hypoxic human renal proximal tubular cells

    Directory of Open Access Journals (Sweden)

    Ding F

    2014-09-01

    Full Text Available Fengan Ding,1 Yiping Li,1 Jing Liu,1 Lei Liu,1 Wenmin Yu,1 Zhi Wang,1 Haifeng Ni,2 Bicheng Liu,2 Pingsheng Chen1,2 1School of Medicine, Southeast University, Nanjing, People’s Republic of China; 2Institute of Nephrology, The Affiliated Zhongda Hospital, Southeast University, Nanjing, People’s Republic of China Background: Gold nanoparticles (GNPs can potentially be used in biomedical fields ranging from therapeutics to diagnostics, and their use will result in increased human exposure. Many studies have demonstrated that GNPs can be deposited in the kidneys, particularly in renal tubular epithelial cells. Chronic hypoxic is inevitable in chronic kidney diseases, and it results in renal tubular epithelial cells that are susceptible to different types of injuries. However, the understanding of the interactions between GNPs and hypoxic renal tubular epithelial cells is still rudimentary. In the present study, we characterized the cytotoxic effects of GNPs in hypoxic renal tubular epithelial cells.Results: Both 5 nm and 13 nm GNPs were synthesized and characterized using various biophysical methods, including transmission electron microscopy, dynamic light scattering, and ultraviolet–visible spectrophotometry. We detected the cytotoxicity of 5 and 13 nm GNPs (0, 1, 25, and 50 nM to human renal proximal tubular cells (HK-2 by Cell Counting Kit-8 assay and lactate dehydrogenase release assay, but we just found the toxic effect in the 5 nm GNP-treated cells at 50 nM dose under hypoxic condition. Furthermore, the transmission electron microscopy images revealed that GNPs were either localized in vesicles or free in the lysosomes in 5 nm GNPs-treated HK-2 cells, and the cellular uptake of the GNPs in the hypoxic cells was significantly higher than that in normoxic cells. In normoxic HK-2 cells, 5 nm GNPs (50 nM treatment could cause autophagy and cell survival. However, in hypoxic conditions, the GNP exposure at the same condition led to the

  19. Relationship of Intracellular Free Ca2+ Concentration and Calcium-activated Chloride Channels of Pulmonary Artery Smooth Muscle Cells in Rats under Hypoxic Conditions

    Institute of Scientific and Technical Information of China (English)

    YANG Zhao; ZHANG Zhenxiang; XU Yongjian; LI Yaqing; YE Tao

    2006-01-01

    To investigate the relationship between intracellular free Ca2+ concentration ([Ca2+]i)and calcium-activated chloride (Clca) channels of pulmonary artery smooth muscle cells (PASMCs) in rats under acute and chronic hypoxic conditions, acute hypoxia-induced contraction was observed in rat pulmonary artery by using routine blood vascular perfusion in vitro. The fluorescence Ca2+indicator Fura-2/AM was used to observe [Ca2+]i of rat PASMCs under normal and chronic hypoxic condition. The effect of Clca channels on PASMCs proliferation was assessed by MTT assay.The Clca channel blockersniflumic acid (NFA) and indaryloxyacetic acid (IAA-94) exerted inhibitory effects on acute hypoxia-evoked contractions in the pulmonary artery. Under chronic hypoxic condition, [Ca2+ ]i was increased. Under normoxic condition, [Ca2+]i was (123.63±18.98) nmol/L, and in hypoxic condition, [Ca2+]i was (281. 75±16.48) nmol/L (P<0.01). Under normoxic condition, [Ca2+]i showed no significant change and no effect on Clca channels was observed (P>0. 05). Chronic hypoxia increased [Ca2+]i which opened Clca channels. The NFA and IAA-94blocked the channels and decreased [Ca2+]i from (281. 75±16.48) nmol/L to (117.66±15.36)nmol/L (P<0.01). MTT assay showed that under chronic hypoxic condition NFA and IAA-94 decreased the value of absorbency (A value) from 0. 459±0. 058 to 0. 224±0. 025 (P<0.01).Hypoxia increased [Ca2+]i which opened Clca channels and had a positive-feedback in [Ca2+]i. Thismay play an important role in hypoxic pulmonary hypertension. Under chronic hypoxic condition,Clca channel may play a part in the regulation of proliferation of PASMCs.

  20. [STRESS AND INFARCT LIMITING EFFECTS OF EARLY HYPOXIC PRECONDITIONING].

    Science.gov (United States)

    Lishmanov, Yu B; Maslov, L N; Sementsov, A S; Naryzhnaya, N V; Tsibulnikov, S Yu

    2015-09-01

    It was established that early hypoxic preconditioning is an adaptive state different from eustress and distress. Hypoxic preconditioning has the cross effects, increasing the tolerance of the heart to ischemia-reperfusion and providing antiulcerogenic effect during immobilization stress.

  1. Peripheral nerve injury is associated with chronic, reversible changes in global DNA methylation in the mouse prefrontal cortex.

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    Maral Tajerian

    Full Text Available Changes in brain structure and cortical function are associated with many chronic pain conditions including low back pain and fibromyalgia. The magnitude of these changes correlates with the duration and/or the intensity of chronic pain. Most studies report changes in common areas involved in pain modulation, including the prefrontal cortex (PFC, and pain-related pathological changes in the PFC can be reversed with effective treatment. While the mechanisms underlying these changes are unknown, they must be dynamically regulated. Epigenetic modulation of gene expression in response to experience and environment is reversible and dynamic. Epigenetic modulation by DNA methylation is associated with abnormal behavior and pathological gene expression in the central nervous system. DNA methylation might also be involved in mediating the pathologies associated with chronic pain in the brain. We therefore tested a whether alterations in DNA methylation are found in the brain long after chronic neuropathic pain is induced in the periphery using the spared nerve injury modal and b whether these injury-associated changes are reversible by interventions that reverse the pathologies associated with chronic pain. Six months following peripheral nerve injury, abnormal sensory thresholds and increased anxiety were accompanied by decreased global methylation in the PFC and the amygdala but not in the visual cortex or the thalamus. Environmental enrichment attenuated nerve injury-induced hypersensitivity and reversed the changes in global PFC methylation. Furthermore, global PFC methylation correlated with mechanical and thermal sensitivity in neuropathic mice. In summary, induction of chronic pain by peripheral nerve injury is associated with epigenetic changes in the brain. These changes are detected long after the original injury, at a long distance from the site of injury and are reversible with environmental manipulation. Changes in brain structure and

  2. Essential Contributions of Serotonin Transporter Inhibition to the Acute and Chronic Actions of Fluoxetine and Citalopram in the SERT Met172 Mouse.

    Science.gov (United States)

    Nackenoff, Alex G; Moussa-Tooks, Alexandra B; McMeekin, Austin M; Veenstra-VanderWeele, Jeremy; Blakely, Randy D

    2016-06-01

    Depression is a common mental illness and a leading cause of disability. The most widely prescribed antidepressant medications are serotonin (5-HT) selective reuptake inhibitors (SSRIs). Although there is much support for 5-HT transporter (SERT) antagonism as a basis of antidepressant efficacy, this evidence is indirect and other targets and mechanisms have been proposed. In order to distinguish SERT-dependent and -independent effects of SSRIs, we developed a knock-in mouse model whereby high-affinity interactions of many antidepressants at SERT have been ablated via knock-in substitution (SERT Met172) without disrupting 5-HT recognition or uptake. Here we utilize the C57BL/6J SERT Met172 model to evaluate SERT dependence for the actions of two widely prescribed SSRIs, fluoxetine and citalopram, in tests sensitive to acute and chronic actions of antidepressants. In the tail suspension and forced swim tests, fluoxetine and citalopram fail to reduce immobility in SERT Met172 mice. In addition, SERT Met172 mice are insensitive to chronic fluoxetine and citalopram administration in the novelty induced hypophagia test (NIH) and fail to exhibit enhanced proliferation or survival of hippocampal stem cells. In both acute and chronic studies, SERT Met172 mice maintained sensitivity to paroxetine, an antidepressant that is unaffected by the Met172 mutation. Together, these studies provide definitive support for an essential role of SERT antagonism in the acute and chronic actions of two commonly used SSRIs in these tests, and reinforce the utility of the SERT Met172 model for isolating SERT/5-HT contributions of drug actions in vivo. PMID:26514584

  3. Development of a Model of Chronic Kidney Disease in the C57BL/6 Mouse with Properties of Progressive Human CKD

    Directory of Open Access Journals (Sweden)

    Zahraa Mohammed-Ali

    2015-01-01

    Full Text Available Chronic kidney disease (CKD is a major healthcare problem with increasing prevalence in the population. CKD leads to end stage renal disease and increases the risk of cardiovascular disease. As such, it is important to study the mechanisms underlying CKD progression. To this end, an animal model was developed to allow the testing of new treatment strategies or molecular targets for CKD prevention. Many underlying risk factors result in CKD but the disease itself has common features, including renal interstitial fibrosis, tubular epithelial cell loss through apoptosis, glomerular damage, and renal inflammation. Further, CKD shows differences in prevalence between the genders with premenopausal women being relatively resistant to CKD. We sought to develop and characterize an animal model with these common features of human CKD in the C57BL/6 mouse. Mice of this genetic background have been used to produce transgenic strains that are commercially available. Thus, a CKD model in this strain would allow the testing of the effects of numerous genes on the severity or progression of CKD with minimal cost. This paper describes such a mouse model of CKD utilizing angiotensin II and deoxycorticosterone acetate as inducers.

  4. Important role of PLC-γ1 in hypoxic increase in intracellular calcium in pulmonary arterial smooth muscle cells.

    Science.gov (United States)

    Yadav, Vishal R; Song, Tengyao; Joseph, Leroy; Mei, Lin; Zheng, Yun-Min; Wang, Yong-Xiao

    2013-02-01

    An increase in intracellular calcium concentration ([Ca(2+)](i)) in pulmonary arterial smooth muscle cells (PASMCs) induces hypoxic cellular responses in the lungs; however, the underlying molecular mechanisms remain incompletely understood. We report, for the first time, that acute hypoxia significantly enhances phospholipase C (PLC) activity in mouse resistance pulmonary arteries (PAs), but not in mesenteric arteries. Western blot analysis and immunofluorescence staining reveal the expression of PLC-γ1 protein in PAs and PASMCs, respectively. The activity of PLC-γ1 is also augmented in PASMCs following hypoxia. Lentiviral shRNA-mediated gene knockdown of mitochondrial complex III Rieske iron-sulfur protein (RISP) to inhibit reactive oxygen species (ROS) production prevents hypoxia from increasing PLC-γ1 activity in PASMCs. Myxothiazol, a mitochondrial complex III inhibitor, reduces the hypoxic response as well. The PLC inhibitor U73122, but not its inactive analog U73433, attenuates the hypoxic vasoconstriction in PAs and hypoxic increase in [Ca(2+)](i) in PASMCs. PLC-γ1 knockdown suppresses its protein expression and the hypoxic increase in [Ca(2+)](i). Hypoxia remarkably increases inositol 1,4,5-trisphosphate (IP(3)) production, which is blocked by U73122. The IP(3) receptor (IP(3)R) antagonist 2-aminoethoxydiphenyl borate (2-APB) or xestospongin-C inhibits the hypoxic increase in [Ca(2+)](i). PLC-γ1 knockdown or U73122 reduces H(2)O(2)-induced increase in [Ca(2+)](i) in PASMCs and contraction in PAs. 2-APB and xestospongin-C produce similar inhibitory effects. In conclusion, our findings provide novel evidence that hypoxia activates PLC-γ1 by increasing RISP-dependent mitochondrial ROS production in the complex III, which causes IP(3) production, IP(3)R opening, and Ca(2+) release, playing an important role in hypoxic Ca(2+) and contractile responses in PASMCs.

  5. Hypoxic ventilatory drive in dogs during thiopental, ketamine, or pentobarbital anesthesia.

    Science.gov (United States)

    Hirshman, C A; McCullough, R E; Cohen, P J; Weil, J V

    1975-12-01

    The ventilatory responses to isocapnic hypoxia and hypercapnia were studied in seven chronically tracheostomized dogs awake and during anesthesia with pentobarbital (30 mg/kg, iv), ketamine, or thiopental (10 and 15 mg/kg, respectively, followed by infusion). Isocapnic hypoxic ventilatory drive (HVD) was expressed as the parameter A such that the higher the A, the greater the hypoxic drive. HVD(A) was significantly reduced from 259 +/- 28 (mean +/- SEM) in awake dogs, to 96 +/- 14 after pentobarbital, 161 +/- 27 after thiopental, and 213 +/- 23 after ketamine. Hypercapnic ventilatory drive (HCVD) as measured by S (slope of the VE-PACO2 response curve) was significantly reduced from 1.3 +/- .32 in awake dogs to 0.4 +/- .13 after pentobarbital, 0.5 +/- .12 after thiopental, and 0.6 +/- .11 after ketamine. In addition, hypercapnia-induced augmentation of hypoxic drive was markedly diminished by the two barbiturates but was unaffected by ketamine. Therefore, ketamine at this dose level afforded greater protection during exposure to hypoxia than did barbiturates. (Key words: Ventilation, hypoxic response; Hypoxia, ventilation; Oxygen, ventilatory response; Carbon dioxide, ventilatory response; Anesthetics, intravenous, ketamine; Anesthetics, intravenous, thiopental; Hypnotics, barbiturates, pentobarbital.) PMID:1190538

  6. HYPOXIC INFLAMMATION, A DEADLY BRIDGE TO MALIGNANT TRANSFORMATION AND A FERTILE SOIL FOR CANCER PREVENTION

    Directory of Open Access Journals (Sweden)

    Kambiz Afrasiabi

    2013-01-01

    Full Text Available The interplay of the inflammatory microenvironment with its hypoxic niche and the potential mechanism by which they lead to malignant transformation has long been the subject of great controversy and continues to be an area of great interest today. In our previous studies we have examined this subject by using Gia2 knock out mice as the focus of our research. These mice are well known for their tendency to develop chronic inflammation in the sub mucosa of their gut, with gradual worsening and development of colon adenocarcinoma in most as they age. It has also attracted our attention that they develop a significant increase in the number of hypoxic niches in their sub mucosa, proven by EF5 staining.In contradistinction to MSI-high colon adenocarcinomas, we have also shown that histone deacetylation rather than MLH1 promoter methylation is the main mechanism of MLH1 and MSH2 deactivation in these mice. Here we show that hypoxic niches evolve under massive selective pressure of the inflammatory microenvironment as a protective shield offering survival advantage by the up regulation of NFKb and its downstream pathways, which indeed independent of true hypoxia leads to stabilization of HIF as well, securing a dual mechanism for perpetuation and expansion of hypoxic niches. We incorporated western blot and Luciferase assay of cells exposed to hypoxia+/-inflammatory cytokines to acquire data.

  7. Brain mechanisms of hypoxic preconditioning%低氧预适应的脑机制

    Institute of Scientific and Technical Information of China (English)

    吕国蔚; 崔秀玉; 赵兰峰; 安仰原; 高翠英

    2004-01-01

    A concept ot tissue adaptation to hypoxia( i.e. hypoxic preconditioning) was developed and its corresponding animal models were reproduced in 1966s. The methods of model reproduction in rat, rabbit, and mouse in particular and the main results are brifly introduced in this review. The tolerance to hypoxia o{ preconditioned animals is significantly increased. Regular changes in animals' behavior, neurophysiology, respiratory and circulatory physiology, neuromorphology in vivo and {unction of brain and spinal cord in vitro are briefly demonstrated. The protective effects in vivo and in vitro of homogenate extract taken from the brain o{ preconditioned animals, neurochemcals and molecular neurobiolcgical alterations are briefly presented. The essence and significance of tissue adaption to hypoxia/hypoxic preconditioning are discussed in the review in terms of evolution and practical implication.

  8. Sugar-coupled 2-nitroimidazoles: novel in vivo markers for hypoxic tumor tissue

    International Nuclear Information System (INIS)

    1-(6-Iodo-60deoxy-β-D-galactopyranosyl)-2-nitroimidazole (IAZG) and 1-(5-iodo-5-deoxy-β-D-arabino-furanosyl)-2-nitroimidazole (IAZA) have been synthesised and labelled with 125I. These compounds were shown to undergo hypoxia-dependant binding with EMT-6 mouse fibrosarcoma cells in vitro with IAZG showing the highest initial binding rate observed so far. Both compounds show selective toxicity toward hypoxic cell in culture. Whole body elimination and biodistribution studies were carried out and indicate general rapid excretion and some selectivity for tumour tissue. IAZG has a maximum tumor to blood ratio of 1.6 at 4 hours while IAZA showed a ratio of 8.7 hours. Both in vitro and in vivo scintigraphic assessment of hypoxic tissue may be possible with these compounds, 21 refs., 2 tabs., 6 figs

  9. Interleukin-33 Drives Activation of Alveolar Macrophages and Airway Inflammation in a Mouse Model of Acute Exacerbation of Chronic Asthma

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    Melissa M. Bunting

    2013-01-01

    Full Text Available We investigated the role of interleukin-33 (IL-33 in airway inflammation in an experimental model of an acute exacerbation of chronic asthma, which reproduces many of the features of the human disease. Systemically sensitized female BALB/c mice were challenged with a low mass concentration of aerosolized ovalbumin for 4 weeks to induce chronic asthmatic inflammation and then received a single moderate-level challenge to trigger acute airway inflammation simulating an asthmatic exacerbation. The inflammatory response and expression of cytokines and activation markers by alveolar macrophages (AM were assessed, as was the effect of pretreatment with a neutralizing antibody to IL-33. Compared to chronically challenged mice, AM from an acute exacerbation exhibited significantly enhanced expression of markers of alternative activation, together with enhanced expression of proinflammatory cytokines and of cell surface proteins associated with antigen presentation. In parallel, there was markedly increased expression of both mRNA and immunoreactivity for IL-33 in the airways. Neutralization of IL-33 significantly decreased both airway inflammation and the expression of proinflammatory cytokines by AM. Collectively, these data indicate that in this model of an acute exacerbation of chronic asthma, IL-33 drives activation of AM and has an important role in the pathogenesis of airway inflammation.

  10. A novel mouse model for the study of the inhibitory effects of chronic ethanol exposure on direct bone formation

    Science.gov (United States)

    Excessive alcohol consumption has been reported to interfere with human bone homeostasis and repair in multiple ways. Previous studies have demonstrated that chronic ethanol exposure in the rat via an intragastric dietary delivery system inhibits direct bone formation during distraction osteogenesis...

  11. Lysyl oxidase mediates hypoxic control of metastasis

    DEFF Research Database (Denmark)

    Erler, Janine Terra; Giaccia, Amato J

    2006-01-01

    Hypoxic cancer cells pose a great challenge to the oncologist because they are especially aggressive, metastatic, and resistant to therapy. Recently, we showed that elevation of the extracellular matrix protein lysyl oxidase (LOX) correlates with metastatic disease and is essential for hypoxia...

  12. Up-regulation of nucleotide excision repair in mouse lung and liver following chronic exposure to aflatoxin B{sub 1} and its dependence on p53 genotype

    Energy Technology Data Exchange (ETDEWEB)

    Mulder, Jeanne E. [Pharmacology and Toxicology Graduate Program, Department of Biomedical and Molecular Sciences, Queen' s University Kingston, Ontario K7L 3N6 (Canada); Bondy, Genevieve S.; Mehta, Rekha [Toxicology Research Division, 2202D, Bureau of Chemical Safety, Food Directorate, Health Products and Food Branch, Health Canada, Ottawa, Ontario K1A 0K9 (Canada); Massey, Thomas E., E-mail: masseyt@queensu.ca [Pharmacology and Toxicology Graduate Program, Department of Biomedical and Molecular Sciences, Queen' s University Kingston, Ontario K7L 3N6 (Canada)

    2014-03-01

    Aflatoxin B{sub 1} (AFB{sub 1}) is biotransformed in vivo into an epoxide metabolite that forms DNA adducts that may induce cancer if not repaired. p53 is a tumor suppressor gene implicated in the regulation of global nucleotide excision repair (NER). Male heterozygous p53 knockout (B6.129-Trp53{sup tm1Brd}N5, Taconic) and wild-type mice were exposed to 0, 0.2 or 1.0 ppm AFB{sub 1} for 26 weeks. NER activity was assessed with an in vitro assay, using AFB{sub 1}-epoxide adducted plasmid DNA as a substrate. For wild-type mice, repair of AFB{sub 1}–N7-Gua adducts was 124% and 96% greater in lung extracts from mice exposed to 0.2 ppm and 1.0 ppm AFB{sub 1} respectively, and 224% greater in liver extracts from mice exposed to 0.2 ppm AFB{sub 1} (p < 0.05). In heterozygous p53 knockout mice, repair of AFB{sub 1}–N7-Gua was only 45% greater in lung extracts from mice exposed to 0.2 ppm AFB{sub 1} (p < 0.05), and no effect was observed in lung extracts from mice treated with 1.0 ppm AFB{sub 1} or in liver extracts from mice treated with either AFB{sub 1} concentration. p53 genotype did not affect basal levels of repair. AFB{sub 1} exposure did not alter repair of AFB{sub 1}-derived formamidopyrimidine adducts in lung or liver extracts of either mouse genotype nor did it affect XPA or XPB protein levels. In summary, chronic exposure to AFB{sub 1} increased NER activity in wild-type mice, and this response was diminished in heterozygous p53 knockout mice, indicating that loss of one allele of p53 limits the ability of NER to be up-regulated in response to DNA damage. - Highlights: • Mice are chronically exposed to low doses of the mycotoxin aflatoxin B{sub 1} (AFB{sub 1}). • The effects of AFB{sub 1} and p53 status on nucleotide excision repair are investigated. • AFB{sub 1} increases nucleotide excision repair in wild type mouse lung and liver. • This increase is attenuated in p53 heterozygous mouse lung and liver. • Results portray the role of p53 in

  13. Differential protein expression in substantia nigra induced by 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine in a mouse model of chronic Parkinson's disease

    Institute of Scientific and Technical Information of China (English)

    Wenbin Tu; Furong Xu; Guoguang Peng

    2008-01-01

    BACKGROUND: To date, a complete protein expression profile of the midbrain substantia nigra in a mouse model of chronic Parkinson's disease, induced by 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP), does not exist. In addition, there are no reports of analysis of differential protein expression.OBJECTIVE: To separate and evaluate MPTP-induced differential protein expression through the use of proteomics in the substantia nigra of a mouse model of chronic Parkinson's disease.DESIGN: Randomized controlled animal study.SETTING: Department of Neurology, the First Affiliated Hospital, Chongqing Medical University.MATERIALS: Sixteen 8-10-week old, healthy, male, C57BL mice, weighing 20-25g, and of clean grade, were provided by the Experimental Animal Center of Chongqing Medical University. The experimental animals were disposed according to ethical criteria. MPTP was provided by Sigma Company, USA; Pdquest 2D image analysis software and gelatum/irradiance image analysis system (ChemiDoc XRS) by Bio-Rad, USA; and Voyager DE-PROMALDI-TOF-MS mass spectroscopy analyzer by ABI Company, USA.METHODS: This study was performed in Chongqing Neurological Laboratory between November 2006 and July 2007. Mice were randomly divided into model and control groups, with 8 mice in each group. Mice in the model group were Received a subcutaneous injection of MPTP (25mg/kg), twice a week, for five successive weeks, to establish a chronic Parkinson's disease model. Mice in the control group 收稿日期 the same volume of a subcutaneous saline injection at the same time points. Mice were sacrificed by anesthesia to rapidly obtain the midbrain for protein separation of the substantia nigra.MAIN OUTCOME MEASURES: (1) 2-ED handbook (Bio-Rad Company) was referenced for two-dimensional electrophoresis. (2) PDQUEST8.0 analytical electrophoresis pattern was adopted to evaluate differential protein expression. (3) Peptide mass finger print map and data were retrieved on http

  14. Lung tumorigenic response of strain A mice exposed to hypoxic cell sensitizers alone and in combination with gamma-radiation

    Energy Technology Data Exchange (ETDEWEB)

    Mian, T.A.; Theiss, J.C.; Grdina, D.J.

    1983-01-01

    The influence of metronidazole, misonidazole, and desmethylmisonidazole on the induction of lung adenomas in the strain A mouse was examined. Two dose levels of the hypoxic cell sensitizers, 0.2 and 0.6 mg/g, were used either alone or in combination with 900 rads of gamma-radiation in a fractionated dose schedule of twice a week for 3 weeks. In the groups of mice which received hypoxic cell sensitizers only, the prevalence and the mean number of lung tumors per mouse were somewhat increased (p less than 0.10) in the group receiving the higher dose (0.6 mg/g) of misonidazole but was not significantly different from results for the control animals in the other two sensitizer groups. The combination of hypoxic cell sensitizer and radiation did not show any significant enhancement of lung tumor response when compared with the group which received radiation only. The dose of radiation used in this study significantly enhanced lung tumor formation in mice when compared with that in the control group. Thus, under the experimental exposure conditions used in this investigation, which were somewhat similar to the exposure conditions occurring in clinical treatment, each of the hypoxic cell sensitizers tested failed to sensitize significantly the mice to the carcinogenic effects of gamma-radiation.

  15. Lung tumorigenic response of strain A mice exposed to hypoxic cell sensitizers alone and in combination with gamma-radiation.

    Science.gov (United States)

    Mian, T A; Theiss, J C; Grdina, D J

    1983-01-01

    The influence of metronidazole, misonidazole, and desmethylmisonidazole on the induction of lung adenomas in the strain A mouse was examined. Two dose levels of the hypoxic cell sensitizers, 0.2 and 0.6 mg/g, were used either alone or in combination with 900 rads of gamma-radiation in a fractionated dose schedule of twice a week for 3 weeks. In the groups of mice which received hypoxic cell sensitizers only, the prevalence and the mean number of lung tumors per mouse were somewhat increased (p less than 0.10) in the group receiving the higher dose (0.6 mg/g) of misonidazole but was not significantly different from results for the control animals in the other two sensitizer groups. The combination of hypoxic cell sensitizer and radiation did not show any significant enhancement of lung tumor response when compared with the group which received radiation only. The dose of radiation used in this study significantly enhanced lung tumor formation in mice when compared with that in the control group. Thus, under the experimental exposure conditions used in this investigation, which were somewhat similar to the exposure conditions occurring in clinical treatment, each of the hypoxic cell sensitizers tested failed to sensitize significantly the mice to the carcinogenic effects of gamma-radiation.

  16. Chronic Unpredictable Stress Decreases Expression of Brain-Derived Neurotrophic Factor (BDNF) in Mouse Ovaries: Relationship to Oocytes Developmental Potential

    OpenAIRE

    Li-Min Wu; Mei-Hong Hu; Xian-Hong Tong; Hui Han; Ni Shen; Ren-Tao Jin; Wei Wang; Gui-Xiang Zhou; Guo-Ping He; Yu-Sheng Liu

    2012-01-01

    BACKGROUND: Brain-derived neurotropic factor (BDNF) was originally described in the nervous system but has been shown to be expressed in ovary tissues recently, acting as a paracrine/autocrine regulator required for developments of follicles and oocytes. Although it is generally accepted that chronic stress impairs female reproduction and decreases the expression of BDNF in limbic structures of central nervous system, which contributes to mood disorder. However, it is not known whether chroni...

  17. YAP is up-regulated in the bronchial airway smooth muscle of the chronic asthma mouse model

    OpenAIRE

    Zhou, Jing; Xu, Fei; Yu, Jing Jing; Zhang, Wei

    2015-01-01

    Asthma is characterized by leukocytic infiltration and tissue remodeling with structural changes including subepithelial fibrosis and ASM cells proliferation. The Hippo pathway is a key regulatory point involved in cell proliferation, fibroblasts, and smooth muscle cell differentiation. In order to disclose the relation between asthma and the Hippo pathway, expression of the Yes-associated protein (YAP), a key gene in the Hippo pathway, in the bronchial smooth muscle of chronic asthma model (...

  18. Identification of a chronic non-neurodegenerative microglia activation state in a mouse model of peroxisomal β-oxidation deficiency.

    Science.gov (United States)

    Verheijden, Simon; Beckers, Lien; Casazza, Andrea; Butovsky, Oleg; Mazzone, Massimiliano; Baes, Myriam

    2015-09-01

    The functional diversity and molecular adaptations of reactive microglia in the chronically inflamed central nervous system (CNS) are poorly understood. We previously showed that mice lacking multifunctional protein 2 (MFP2), a pivotal enzyme in peroxisomal β-oxidation, persistently accumulate reactive myeloid cells in the gray matter of the CNS. Here, we show that the increased numbers of myeloid cells solely derive from the proliferation of resident microglia and not from infiltrating monocytes. We defined the signature of Mfp2(-/-) microglia by gene expression profiling after acute isolation, which was validated by quantitative polymerase reaction (qPCR), immunohistochemical, and flow cytometric analysis. The features of Mfp2(-/-) microglia were compared with those from SOD1(G93A) mice, an amyotrophic lateral sclerosis model. In contrast to the neurodegenerative milieu of SOD1(G93A) spinal cord, neurons were intact in Mfp2(-/-) brain and Mfp2(-/-) microglia lacked signs of phagocytic and neurotoxic activity. The chronically reactive state of Mfp2(-/-) microglia was accompanied by the downregulation of markers that specify the unique microglial signature in homeostatic conditions. In contrast, mammalian target of rapamycin (mTOR) and downstream glycolytic and protein translation pathways were induced, indicative of metabolic adaptations. Mfp2(-/-) microglia were immunologically activated but not polarized to a pro- or anti-inflammatory phenotype. A peripheral lipopolysaccharide challenge provoked an exaggerated inflammatory response in Mfp2(-/-) brain, consistent with a primed state. Taken together, we demonstrate that chronic activation of resident microglia does not necessarily lead to phagocytosis nor overt neurotoxicity.

  19. Chronic Exposure to Arsenic in the Drinking Water Alters the Expression of Immune Response Genes in Mouse Lung

    Science.gov (United States)

    Kozul, Courtney D.; Hampton, Thomas H.; Davey, Jennifer C.; Gosse, Julie A.; Nomikos, Athena P.; Eisenhauer, Phillip L.; Weiss, Daniel J.; Thorpe, Jessica E.; Ihnat, Michael A.; Hamilton, Joshua W.

    2009-01-01

    Background Chronic exposure to drinking water arsenic is a significant worldwide environmental health concern. Exposure to As is associated with an increased risk of lung disease, which may make it a unique toxicant, because lung toxicity is usually associated with inhalation rather than ingestion. Objectives The goal of this study was to examine mRNA and protein expression changes in the lungs of mice exposed chronically to environmentally relevant concentrations of As in the food or drinking water, specifically examining the hypothesis that As may preferentially affect gene and protein expression related to immune function as part of its mechanism of toxicant action. Methods C57BL/6J mice fed a casein-based AIN-76A defined diet were exposed to 10 or 100 ppb As in drinking water or food for 5–6 weeks. Results Whole genome transcriptome profiling of animal lungs revealed significant alterations in the expression of many genes with functions in cell adhesion and migration, channels, receptors, differentiation and proliferation, and, most strikingly, aspects of the innate immune response. Confirmation of mRNA and protein expression changes in key genes of this response revealed that genes for interleukin 1β, interleukin 1 receptor, a number of toll-like receptors, and several cytokines and cytokine receptors were significantly altered in the lungs of As-exposed mice. Conclusions These findings indicate that chronic low-dose As exposure at the current U.S. drinking-water standard can elicit effects on the regulation of innate immunity, which may contribute to altered disease risk, particularly in lung. PMID:19654921

  20. Effect of topical application of antioxidants and free radical scavengers on protection of hairless mouse skin exposed to chronic doses of ultraviolet B

    International Nuclear Information System (INIS)

    treatment, respectively. Conclusion: Data from these studies suggest that low level chronic exposures to UV can lead to alteration of the skin, like epidermal thickening and appearance of sunburn cells. The data also indicates that a mix of common antioxidants and free radical scavengers are photoprotective against chronic skin damage in the hairless mouse skin model. (au)

  1. Effect of topical application of antioxidants and free radical scavengers on protection of hairless mouse skin exposed to chronic doses of ultraviolet B

    Energy Technology Data Exchange (ETDEWEB)

    Muizzuddin, N.; Shakoori, A.R. [Univ. of the Punjab, Dept. of Zoology, Cell and Molecular Biology Lab., Lahore (Pakistan); Marenus, K.D. [SUNY at Stonybrook, Stonybrook, NY (United States)

    1998-11-01

    treatment, respectively. Conclusion: Data from these studies suggest that low level chronic exposures to UV can lead to alteration of the skin, like epidermal thickening and appearance of sunburn cells. The data also indicates that a mix of common antioxidants and free radical scavengers are photoprotective against chronic skin damage in the hairless mouse skin model. (au)

  2. Impaired adult hippocampal neurogenesis and its partial reversal by chronic treatment of fluoxetine in a mouse model of Angelman syndrome.

    Science.gov (United States)

    Godavarthi, Swetha K; Dey, Parthanarayan; Sharma, Ankit; Jana, Nihar Ranjan

    2015-09-01

    Angelman syndrome (AS) is a neurodevelopmental disorder characterized by severe cognitive and motor deficits, caused by the loss of function of maternally inherited Ube3a. Ube3a-maternal deficient mice (AS model mice) recapitulate many essential features of AS, but how the deficiency of Ube3a lead to such behavioural abnormalities is poorly understood. Here we have demonstrated significant impairment of adult hippocampal neurogenesis in AS mice brain. Although, the number of BrdU and Ki67-positive cell in the hippocampal DG region was nearly equal at early postnatal days among wild type and AS mice, they were significantly reduced in adult AS mice compared to wild type controls. Reduced number of doublecortin-positive immature neurons in this region of AS mice further indicated impaired neurogenesis. Unaltered BrdU and Ki67-positive cells number in the sub ventricular zone of adult AS mice brain along with the absence of imprinted expression of Ube3a in the neural progenitor cell suggesting that Ube3a may not be directly linked with altered neurogenesis. Finally, we show that the impaired hippocampal neurogenesis in these mice can be partially rescued by the chronic treatment of antidepressant fluoxetine. These results suggest that the chronic stress may lead to reduced hippocampal neurogenesis in AS mice and that impaired neurogenesis could contribute to cognitive disturbances observed in these mice. PMID:26231800

  3. Inflammatory responses in hypoxic ischemic encephalopathy

    OpenAIRE

    Liu, Fudong; McCullough, Louise D.

    2013-01-01

    Inflammation plays a critical role in mediating brain injury induced by neonatal hypoxic ischemic encephalopathy (HIE). The mechanisms underlying inflammatory responses to ischemia may be shared by neonatal and adult brains; however, HIE exhibits a unique inflammation phenotype that results from the immaturity of the neonatal immune system. This review will discuss the current knowledge concerning systemic and local inflammatory responses in the acute and subacute stages of HIE. The key compo...

  4. Protection of Cardiomyocytes from Ischemic/Hypoxic Cell Death via Drbp1 and pMe2GlyDH in Cardio-specific ARC Transgenic Mice*

    Science.gov (United States)

    Pyo, Jong-Ok; Nah, Jihoon; Kim, Hyo-Jin; Chang, Jae-Woong; Song, Young-Wha; Yang, Dong-Kwon; Jo, Dong-Gyu; Kim, Hyung-Ryong; Chae, Han-Jung; Chae, Soo-Wan; Hwang, Seung-Yong; Kim, Seung-Jun; Kim, Hyo-Joon; Cho, Chunghee; Oh, Chang-Gyu; Park, Woo Jin; Jung, Yong-Keun

    2008-01-01

    The ischemic death of cardiomyocytes is associated in heart disease and heart failure. However, the molecular mechanism underlying ischemic cell death is not well defined. To examine the function of apoptosis repressor with a caspase recruitment domain (ARC) in the ischemic/hypoxic damage of cardiomyocytes, we generated cardio-specific ARC transgenic mice using a mouse α-myosin heavy chain promoter. Compared with the control, the hearts of ARC transgenic mice showed a 3-fold overexpression of ARC. Langendoff preparation showed that the hearts isolated from ARC transgenic mice exhibited improved recovery of contractile performance during reperfusion. The cardiomyocytes cultured from neonatal ARC transgenic mice were significantly resistant to hypoxic cell death. Furthermore, the ARC C-terminal calcium-binding domain was as potent to protect cardiomyocytes from hypoxic cell death as ARC. Genome-wide RNA expression profiling uncovered a list of genes whose expression was changed (>2-fold) in ARC transgenic mice. Among them, expressional regulation of developmentally regulated RNA-binding protein 1 (Drbp1) or the dimethylglycine dehydrogenase precursor (pMe2GlyDH) affected hypoxic death of cardiomyocytes. These results suggest that ARC may protect cardiomyocytes from hypoxic cell death by regulating its downstream, Drbp1 and pMe2GlyDH, shedding new insights into the protection of heart from hypoxic damages. PMID:18782777

  5. Transcriptomic changes in human renal proximal tubular cells revealed under hypoxic conditions by RNA sequencing.

    Science.gov (United States)

    Yu, Wenmin; Li, Yiping; Wang, Zhi; Liu, Lei; Liu, Jing; Ding, Fengan; Zhang, Xiaoyi; Cheng, Zhengyuan; Chen, Pingsheng; Dou, Jun

    2016-09-01

    Chronic hypoxia often occurs among patients with chronic kidney disease (CKD). Renal proximal tubular cells may be the primary target of a hypoxic insult. However, the underlying transcriptional mechanisms remain undefined. In this study, we revealed the global changes in gene expression in HK‑2 human renal proximal tubular cells under hypoxic and normoxic conditions. We analyzed the transcriptome of HK‑2 cells exposed to hypoxia for 24 h using RNA sequencing. A total of 279 differentially expressed genes was examined, as these genes could potentially explain the differences in HK‑2 cells between hypoxic and normoxic conditions. Moreover, 17 genes were validated by qPCR, and the results were highly concordant with the RNA seqencing results. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were performed to better understand the functions of these differentially expressed genes. The upregulated genes appeared to be significantly enriched in the pathyway of extracellular matrix (ECM)-receptor interaction, and in paticular, the pathway of renal cell carcinoma was upregulated under hypoxic conditions. The downregulated genes were enriched in the signaling pathway related to antigen processing and presentation; however, the pathway of glutathione metabolism was downregulated. Our analysis revealed numerous novel transcripts and alternative splicing events. Simultaneously, we also identified a large number of single nucleotide polymorphisms, which will be a rich resource for future marker development. On the whole, our data indicate that transcriptome analysis provides valuable information for a more in depth understanding of the molecular mechanisms in CKD and renal cell carcinoma. PMID:27432315

  6. Chronic Exposure to Androgenic-Anabolic Steroids Exacerbates Axonal Injury and Microgliosis in the CHIMERA Mouse Model of Repetitive Concussion.

    Science.gov (United States)

    Namjoshi, Dhananjay R; Cheng, Wai Hang; Carr, Michael; Martens, Kris M; Zareyan, Shahab; Wilkinson, Anna; McInnes, Kurt A; Cripton, Peter A; Wellington, Cheryl L

    2016-01-01

    Concussion is a serious health concern. Concussion in athletes is of particular interest with respect to the relationship of concussion exposure to risk of chronic traumatic encephalopathy (CTE), a neurodegenerative condition associated with altered cognitive and psychiatric functions and profound tauopathy. However, much remains to be learned about factors other than cumulative exposure that could influence concussion pathogenesis. Approximately 20% of CTE cases report a history of substance use including androgenic-anabolic steroids (AAS). How acute, chronic, or historical AAS use may affect the vulnerability of the brain to concussion is unknown. We therefore tested whether antecedent AAS exposure in young, male C57Bl/6 mice affects acute behavioral and neuropathological responses to mild traumatic brain injury (TBI) induced with the CHIMERA (Closed Head Impact Model of Engineered Rotational Acceleration) platform. Male C57Bl/6 mice received either vehicle or a cocktail of three AAS (testosterone, nandrolone and 17α-methyltestosterone) from 8-16 weeks of age. At the end of the 7th week of treatment, mice underwent two closed-head TBI or sham procedures spaced 24 h apart using CHIMERA. Post-repetitive TBI (rTBI) behavior was assessed for 7 d followed by tissue collection. AAS treatment induced the expected physiological changes including increased body weight, testicular atrophy, aggression and downregulation of brain 5-HT1B receptor expression. rTBI induced behavioral deficits, widespread axonal injury and white matter microgliosis. While AAS treatment did not worsen post-rTBI behavioral changes, AAS-treated mice exhibited significantly exacerbated axonal injury and microgliosis, indicating that AAS exposure can alter neuronal and innate immune responses to concussive TBI. PMID:26784694

  7. Antidepressant-like effects of Sanyuansan in the mouse forced swim test, tail suspension test, and chronic mild stress model.

    Science.gov (United States)

    Yan, Shuo; You, Zi-Li; Zhao, Qiu-Ying; Peng, Cheng; He, Gang; Gou, Xiao-Jun; Lin, Bin

    2015-12-01

    Natural products have been widely reported as effective therapeutic alternatives for treatment of depression. Sanyuansan is a compound recipe composed of ginseng total saponins, fish oil, and valeriana. The aims of this study were to validate whether Sanyuansan has antidepressant-like effects through acute behavioral tests including the forced swimming test (FST), tail suspension test (TST), locomotor activity test, and chronic mild stress (CMS) mice model of depression. C57BL/6 mice were given oral administration of 30 mg/kg imipramine, Sanyuansan, and saline, respectively. The acute behavioral tests including the TST, FST, and locomotor activity test were done after the administration of drugs for consecutively three times (24 hours, 1 hour, and 0.5 hour prior to the tests). Furthermore, the sucrose preference and the serum corticosterone level of mice in the CMS model were examined. Sanyuansan only at 900 mg/kg markedly reduced immobility time in the TST compared with the saline-treated group of mice. Sanyuansan at doses of 225 mg/kg, 450 mg/kg, and 900 mg/kg significantly reduced immobility time of mice in the FST. Sanyuansan reversed the CMS-induced anhedonia and hyperactivation of the hypothalamus-pituitary-adrenal axis. In addition, our results showed that neither imipramine nor Sanyuansan at any dosage increased spontaneous motor activity. These results suggested that Sanyuansan induced significant antidepressant-like effects in mice in both acute and chronic animal models, which seemed unlikely to be attributed to an increase in locomotor activities of mice, and had no sedative-like effects.

  8. Chronic Exposure to Androgenic-Anabolic Steroids Exacerbates Axonal Injury and Microgliosis in the CHIMERA Mouse Model of Repetitive Concussion.

    Directory of Open Access Journals (Sweden)

    Dhananjay R Namjoshi

    Full Text Available Concussion is a serious health concern. Concussion in athletes is of particular interest with respect to the relationship of concussion exposure to risk of chronic traumatic encephalopathy (CTE, a neurodegenerative condition associated with altered cognitive and psychiatric functions and profound tauopathy. However, much remains to be learned about factors other than cumulative exposure that could influence concussion pathogenesis. Approximately 20% of CTE cases report a history of substance use including androgenic-anabolic steroids (AAS. How acute, chronic, or historical AAS use may affect the vulnerability of the brain to concussion is unknown. We therefore tested whether antecedent AAS exposure in young, male C57Bl/6 mice affects acute behavioral and neuropathological responses to mild traumatic brain injury (TBI induced with the CHIMERA (Closed Head Impact Model of Engineered Rotational Acceleration platform. Male C57Bl/6 mice received either vehicle or a cocktail of three AAS (testosterone, nandrolone and 17α-methyltestosterone from 8-16 weeks of age. At the end of the 7th week of treatment, mice underwent two closed-head TBI or sham procedures spaced 24 h apart using CHIMERA. Post-repetitive TBI (rTBI behavior was assessed for 7 d followed by tissue collection. AAS treatment induced the expected physiological changes including increased body weight, testicular atrophy, aggression and downregulation of brain 5-HT1B receptor expression. rTBI induced behavioral deficits, widespread axonal injury and white matter microgliosis. While AAS treatment did not worsen post-rTBI behavioral changes, AAS-treated mice exhibited significantly exacerbated axonal injury and microgliosis, indicating that AAS exposure can alter neuronal and innate immune responses to concussive TBI.

  9. Detection of hypoxic cells with the 2-nitroimidazole, EF5, correlates with early redox changes in rat brain after perinatal hypoxia-ischemia.

    Science.gov (United States)

    Bergeron, M; Evans, S M; Sharp, F R; Koch, C J; Lord, E M; Ferriero, D M

    1999-01-01

    The hypoxia-dependent activation of nitroheterocyclic drugs by cellular nitroreductases leads to the formation of intracellular adducts between the drugs and cellular macromolecules. Because this covalent binding is maximal in the absence of oxygen, detection of bound adducts provides an assay for estimating the degree of cellular hypoxia in vivo. Using a pentafluorintated derivative of etanidazole called EF5, we studied the distribution of EF5 adducts in seven-day-old rats subjected to different treatments which decrease the level of oxygen in the brain. EF5 solution was administered intraperitoneally 30 min prior to each treatment. The effect of acute and chronic hypoxia on EF5 adduct formation (binding) was studied in the brain of newborn rats exposed to global hypoxia (8% O2 for 30, 90 or 150 min) and in the brain of chronically hypoxic rat pups with congenital cardiac defects (Wistar Kyoto). The effect of combined hypoxia-ischemia was investigated in rat pups subjected to right carotid coagulation and concurrent exposure to 8% O2 for 30, 90 or 150 min. Brains were frozen immediately at the end of each treatment. Using a Cy3-conjugated monoclonal mouse antibody (ELK3-51) raised against EF5 adducts, hypoxic cells within brain regions were visualized by fluorescence immunocytochemistry. Brains from controls or vehicle-injected animals showed no EF5 binding. Notably, brains from animals which were chronically hypoxemic as a result of congenital cardiac defects also showed no EF5 binding. A short exposure (30 min) to hypoxia or to combined hypoxia-ischemia resulted in increased background stain and few scattered cells with low-intensity immunostaining. Acute hypoxia exposure of at least 90-150 min, which in this age animal does not result in frank cellular damage, produced patchy areas of low- to moderate-intensity fluorescence scattered throughout the brain. In contrast, 90-150 min of hypoxia-ischemia was associated with intense immunofluorescence in the

  10. Action of SNAIL1 in Cardiac Myofibroblasts Is Important for Cardiac Fibrosis following Hypoxic Injury

    Science.gov (United States)

    Biswas, Hirak; Longmore, Gregory D.

    2016-01-01

    Hypoxic injury to the heart results in cardiac fibrosis that leads to cardiac dysfunction and heart failure. SNAIL1 is a zinc finger transcription factor implicated in fibrosis following organ injury and cancer. To determine if the action of SNAIL1 contributed to cardiac fibrosis following hypoxic injury, we used an endogenous SNAIL1 bioluminescence reporter mice, and SNAIL1 knockout mouse models. Here we report that SNAIL1 expression is upregulated in the infarcted heart, especially in the myofibroblasts. Utilizing primary cardiac fibroblasts in ex vivo cultures we find that pro-fibrotic factors and collagen I increase SNAIL1 protein level. SNAIL1 is required in cardiac fibroblasts for the adoption of myofibroblast fate, collagen I expression and expression of fibrosis-related genes. Taken together this data suggests that SNAIL1 expression is induced in the cardiac fibroblasts after hypoxic injury and contributes to myofibroblast phenotype and a fibrotic scar formation. Resultant collagen deposition in the scar can maintain elevated SNAIL1 expression in the myofibroblasts and help propagate fibrosis. PMID:27706205

  11. Effects of Yulangsan polysaccharide on monoamine neurotransmitters, adenylate cyclase activity and brain-derived neurotrophic factor expression in a mouse model of depression induced by unpredictable chronic mild stress☆

    OpenAIRE

    Liang, Shuang; Huang, Renbin; Lin, Xing; Huang, Jianchun; Huang, Zhongshi; Liu, Huagang

    2012-01-01

    The present study established a mouse model of depression induced by unpredictable chronic mild stress. The model mice were treated with Yulangsan polysaccharide (YLSPS; 150, 300 and 600 mg/kg) for 21 days, and compared with fluoxetine-treated and normal control groups. Enzyme-linked immunosorbent assay, radioimmunity and immunohistochemical staining showed that following treatment with YLSPS (300 and 600 mg/kg), monoamine neurotransmitter levels, prefrontal cortex adenylate cyclase activity ...

  12. The grey mouse lemur uses season-dependent fat or protein sparing strategies to face chronic food restriction.

    Directory of Open Access Journals (Sweden)

    Sylvain Giroud

    Full Text Available During moderate calorie restriction (CR the heterotherm Microcebus murinus is able to maintain a stable energy balance whatever the season, even if only wintering animals enter into torpor. To understand its energy saving strategies to respond to food shortages, we assessed protein and energy metabolisms associated with wintering torpor expression or summering torpor avoidance. We investigated body composition, whole body protein turnover, and daily energy expenditure (DEE, during a graded (40 and 80% 35-day CR in short-days (winter; SD40 and SD80, respectively and long-days (summer; LD40 and LD80, respectively acclimated animals. LD40 animals showed no change in fat mass (FM but a 12% fat free mass (FFM reduction. Protein balance being positive after CR, the FFM loss was early and rapid. The 25% DEE reduction, in LD40 group was mainly explained by FFM changes. LD80 animals showed a steady body mass loss and were excluded from the CR trial at day 22, reaching a survival-threatened body mass. No data were available for this group. SD40 animals significantly decreased their FM level by 21%, but maintained FFM. Protein sparing was achieved through a 35 and 39% decrease in protein synthesis and catabolism (protein turnover, respectively, overall maintaining nitrogen balance. The 21% reduction in energy requirement was explained by the 30% nitrogen flux drop but also by torpor as DEE FFM-adjusted remained 13% lower compared to ad-libitum. SD80 animals were unable to maintain energy and nitrogen balances, losing both FM and FFM. Thus summering mouse lemurs equilibrate energy balance by a rapid loss of active metabolic mass without using torpor, whereas wintering animals spare protein and energy through increased torpor expression. Both strategies have direct fitness implication: 1 to maintain activities at a lower body size during the mating season and 2 to preserve an optimal wintering muscle mass and function.

  13. Chronic hyperglycemia induced via the heterozygous knockout of Pdx1 worsens neuropathological lesion in an Alzheimer mouse model.

    Science.gov (United States)

    Guo, Chuang; Zhang, Shuai; Li, Jia-Yi; Ding, Chen; Yang, Zhao-Hui; Chai, Rui; Wang, Xu; Wang, Zhan-You

    2016-01-01

    Compelling evidence has indicated that dysregulated glucose metabolism links Alzheimer's disease (AD) and diabetes mellitus (DM) via glucose metabolic products. Nevertheless, because of the lack of appropriate animal models, whether chronic hyperglycemia worsens AD pathologies in vivo remains to be confirmed. Here, we crossed diabetic mice (Pdx1(+/-) mice) with Alzheimer mice (APP/PS1 transgenic mice) to generate Pdx1(+/-)/APP/PS1. We identified robust increases in tau phosphorylation, the loss of the synaptic spine protein, amyloid-β (Aβ) deposition and plaque formation associated with increased microglial and astrocyte activation proliferation, which lead to exacerbated memory and cognition deficits. More importantly, we also observed increased glucose intolerance accompanied by Pdx1 reduction, the formation of advanced glycation end-products (AGEs), and the activation of the receptor for AGEs (RAGE) signaling pathways during AD progression; these changes are thought to contribute to the processing of Aβ precursor proteins and result in increased Aβ generation and decreased Aβ degradation. Protein glycation, increased oxidative stress and inflammation via hyperglycemia are the primary mechanisms involved in the pathophysiology of AD. These results indicate the pathological relationship between these diseases and provide novel insights suggesting that glycemic control may be beneficial for decreasing the incidence of AD in diabetic patients and delaying AD progression. PMID:27406855

  14. Therapeutic and space radiation exposure of mouse brain causes impaired DNA repair response and premature senescence by chronic oxidant production.

    Science.gov (United States)

    Suman, Shubhankar; Rodriguez, Olga C; Winters, Thomas A; Fornace, Albert J; Albanese, Chris; Datta, Kamal

    2013-08-01

    Despite recent epidemiological evidences linking radiation exposure and a number of human ailments including cancer, mechanistic understanding of how radiation inflicts long-term changes in cerebral cortex, which regulates important neuronal functions, remains obscure. The current study dissects molecular events relevant to pathology in cerebral cortex of 6 to 8 weeks old female C57BL/6J mice two and twelve months after exposure to a γ radiation dose (2 Gy) commonly employed in fractionated radiotherapy. For a comparative study, effects of 1.6 Gy heavy ion 56Fe radiation on cerebral cortex were also investigated, which has implications for space exploration. Radiation exposure was associated with increased chronic oxidative stress, oxidative DNA damage, lipid peroxidation, and apoptosis. These results when considered with decreased cortical thickness, activation of cell-cycle arrest pathway, and inhibition of DNA double strand break repair factors led us to conclude to our knowledge for the first time that radiation caused aging-like pathology in cerebral cortical cells and changes after heavy ion radiation were more pronounced than γ radiation. PMID:23928451

  15. Differential Features between Chronic Skin Inflammatory Diseases Revealed in Skin-Humanized Psoriasis and Atopic Dermatitis Mouse Models.

    Science.gov (United States)

    Carretero, Marta; Guerrero-Aspizua, Sara; Illera, Nuria; Galvez, Victoria; Navarro, Manuel; García-García, Francisco; Dopazo, Joaquin; Jorcano, Jose Luis; Larcher, Fernando; del Rio, Marcela

    2016-01-01

    Psoriasis and atopic dermatitis are chronic and relapsing inflammatory diseases of the skin affecting a large number of patients worldwide. Psoriasis is characterized by a T helper type 1 and/or T helper type 17 immunological response, whereas acute atopic dermatitis lesions exhibit T helper type 2-dominant inflammation. Current single gene and signaling pathways-based models of inflammatory skin diseases are incomplete. Previous work allowed us to model psoriasis in skin-humanized mice through proper combinations of inflammatory cell components and disruption of barrier function. Herein, we describe and characterize an animal model for atopic dermatitis using similar bioengineered-based approaches, by intradermal injection of human T helper type 2 lymphocytes in regenerated human skin after partial removal of stratum corneum. In this work, we have extensively compared this model with the previous and an improved version of the psoriasis model, in which T helper type 1 and/or T helper type 17 lymphocytes replace exogenous cytokines. Comparative expression analyses revealed marked differences in specific epidermal proliferation and differentiation markers and immune-related molecules, including antimicrobial peptides. Likewise, the composition of the dermal inflammatory infiltrate presented important differences. The availability of accurate and reliable animal models for these diseases will contribute to the understanding of the pathogenesis and provide valuable tools for drug development and testing. PMID:26763433

  16. The antifibrotic drug pirfenidone promotes pulmonary cavitation and drug resistance in a mouse model of chronic tuberculosis

    Science.gov (United States)

    Ahidjo, Bintou A.; Maiga, Mariama C.; Ihms, Elizabeth A.; Maiga, Mamoudou; Ordonez, Alvaro A.; Cheung, Laurene S.; Beck, Sarah; Andrade, Bruno B.; Jain, Sanjay

    2016-01-01

    Pirfenidone is a recently approved antifibrotic drug for the treatment of idiopathic pulmonary fibrosis (IPF). Because tuberculosis (TB) is characterized by granulomatous inflammation in conjunction with parenchymal destruction and replacement fibrosis, we sought to determine whether the addition of pirfenidone as an adjunctive, host-directed therapy provides a beneficial effect during antimicrobial treatment of TB. We hypothesized that pirfenidone’s antiinflammatory and antifibrotic properties would reduce inflammatory lung damage and increase antimicrobial drug penetration in granulomas to accelerate treatment response. The effectiveness of adjunctive pirfenidone during TB drug therapy was evaluated using a murine model of chronic TB. Mice treated with standard therapy 2HRZ/4HR (H, isoniazid; R, rifampin; and Z, pyrazinamide) were compared with 2 alternative regimens containing pirfenidone (Pf) (2HRZPf/4HRPf and 2HRZPf/4HR). Contrary to our hypothesis, adjunctive pirfenidone use leads to reduced bacterial clearance and increased relapse rates. This treatment failure is closely associated with the emergence of isoniazid monoresistant bacilli, increased cavitation, and significant lung pathology. While antifibrotic agents may eventually be used as part of adjunctive host-directed therapy of TB, this study clearly demonstrates that caution must be exercised. Moreover, as pirfenidone becomes more widely used in clinical practice, increased patient monitoring would be required in endemic TB settings. PMID:27699232

  17. The antifibrotic drug pirfenidone promotes pulmonary cavitation and drug resistance in a mouse model of chronic tuberculosis

    Science.gov (United States)

    Ahidjo, Bintou A.; Maiga, Mariama C.; Ihms, Elizabeth A.; Maiga, Mamoudou; Ordonez, Alvaro A.; Cheung, Laurene S.; Beck, Sarah; Andrade, Bruno B.; Jain, Sanjay

    2016-01-01

    Pirfenidone is a recently approved antifibrotic drug for the treatment of idiopathic pulmonary fibrosis (IPF). Because tuberculosis (TB) is characterized by granulomatous inflammation in conjunction with parenchymal destruction and replacement fibrosis, we sought to determine whether the addition of pirfenidone as an adjunctive, host-directed therapy provides a beneficial effect during antimicrobial treatment of TB. We hypothesized that pirfenidone’s antiinflammatory and antifibrotic properties would reduce inflammatory lung damage and increase antimicrobial drug penetration in granulomas to accelerate treatment response. The effectiveness of adjunctive pirfenidone during TB drug therapy was evaluated using a murine model of chronic TB. Mice treated with standard therapy 2HRZ/4HR (H, isoniazid; R, rifampin; and Z, pyrazinamide) were compared with 2 alternative regimens containing pirfenidone (Pf) (2HRZPf/4HRPf and 2HRZPf/4HR). Contrary to our hypothesis, adjunctive pirfenidone use leads to reduced bacterial clearance and increased relapse rates. This treatment failure is closely associated with the emergence of isoniazid monoresistant bacilli, increased cavitation, and significant lung pathology. While antifibrotic agents may eventually be used as part of adjunctive host-directed therapy of TB, this study clearly demonstrates that caution must be exercised. Moreover, as pirfenidone becomes more widely used in clinical practice, increased patient monitoring would be required in endemic TB settings.

  18. YAP is up-regulated in the bronchial airway smooth muscle of the chronic asthma mouse model.

    Science.gov (United States)

    Zhou, Jing; Xu, Fei; Yu, Jing Jing; Zhang, Wei

    2015-01-01

    Asthma is characterized by leukocytic infiltration and tissue remodeling with structural changes including subepithelial fibrosis and ASM cells proliferation. The Hippo pathway is a key regulatory point involved in cell proliferation, fibroblasts, and smooth muscle cell differentiation. In order to disclose the relation between asthma and the Hippo pathway, expression of the Yes-associated protein (YAP), a key gene in the Hippo pathway, in the bronchial smooth muscle of chronic asthma model (CAM) was studied. 40 mice were randomly divided into control (wide type) and experimental group to construct CAM using chicken ovalbumin (OVA). Pathological changes of the lung tissues were observed in the CAM mice compared with the control using HE staining method. Immunohistochemistry (IHC) was used to detect if YAP protein is expressed in the lung tissues. The pathological changes of the CAM group showed that a large number of inflammatory cells infiltration including mainly lymphocytes and a small amount of eosinophilic, with the presence of certain airway smooth muscle hyperplasia, was observed in comparison with the control. IHC results showed that the YAP protein was significantly increased compared with the control groups (P bronchial airway tissues of the CAM mice, and could be used as an indicator for asthma. PMID:26617833

  19. Chronic hyperglycemia induced via the heterozygous knockout of Pdx1 worsens neuropathological lesion in an Alzheimer mouse model

    Science.gov (United States)

    Guo, Chuang; Zhang, Shuai; Li, Jia-Yi; Ding, Chen; Yang, Zhao-Hui; Chai, Rui; Wang, Xu; Wang, Zhan-You

    2016-01-01

    Compelling evidence has indicated that dysregulated glucose metabolism links Alzheimer’s disease (AD) and diabetes mellitus (DM) via glucose metabolic products. Nevertheless, because of the lack of appropriate animal models, whether chronic hyperglycemia worsens AD pathologies in vivo remains to be confirmed. Here, we crossed diabetic mice (Pdx1+/− mice) with Alzheimer mice (APP/PS1 transgenic mice) to generate Pdx1+/−/APP/PS1. We identified robust increases in tau phosphorylation, the loss of the synaptic spine protein, amyloid-β (Aβ) deposition and plaque formation associated with increased microglial and astrocyte activation proliferation, which lead to exacerbated memory and cognition deficits. More importantly, we also observed increased glucose intolerance accompanied by Pdx1 reduction, the formation of advanced glycation end-products (AGEs), and the activation of the receptor for AGEs (RAGE) signaling pathways during AD progression; these changes are thought to contribute to the processing of Aβ precursor proteins and result in increased Aβ generation and decreased Aβ degradation. Protein glycation, increased oxidative stress and inflammation via hyperglycemia are the primary mechanisms involved in the pathophysiology of AD. These results indicate the pathological relationship between these diseases and provide novel insights suggesting that glycemic control may be beneficial for decreasing the incidence of AD in diabetic patients and delaying AD progression. PMID:27406855

  20. Isolation of a novel chronic lymphocytic leukemic (CLL) cell line and development of an in vivo mouse model of CLL.

    Science.gov (United States)

    Kellner, Joshua; Wierda, William; Shpall, Elizabeth; Keating, Michael; McNiece, Ian

    2016-01-01

    Leukemic cell lines have become important tools for studies of disease providing a monoclonal cell population that can be extensively expanded in vitro while preserving leukemic cellular characteristics. However, studies of chronic lymphocytic leukemia (CLL) have been impeded in part by the lack of continuous human cell lines. CLL cells have a high spontaneous apoptosis rate in vitro and exhibit minimal proliferation in xenograft models. Therefore, there is a need for development of primary CLL cell lines and we describe the isolation of such a line from the bone marrow of a CLL patient (17p deletion and TP53 mutation) which has been in long term culture for more than 12 months with continuous proliferation. The CLL cell line (termed MDA-BM5) which was generated in vitro with continuous co-culture on autologous stromal cells is CD19+CD5+ and shows an identical pattern of somatic hypermutation as determined in the patient's bone marrow (BM), confirming the origin of the cells from the original CLL clone. MDA-BM5 cells were readily transplantable in NOD/SCID gamma null mice (NSG) with disease developing in the BM, liver and spleen. BM cells from quaternary serial transplantation in NSG mice demonstrated the presence of CD19+CD5+ cells with Ig restricted to lambda which is consistent with the original patient cells. These studies describe a new CLL cell line from a patient with del(17p) that provides a unique model for in vitro and in vivo studies. PMID:26601610

  1. Chronic alterations in growth hormone/insulin-like growth factor-I signaling lead to changes in mouse tendon structure

    DEFF Research Database (Denmark)

    Nielsen, R H; Clausen, N M; Schjerling, P;

    2014-01-01

    The growth hormone/insulin-like growth factor-I (GH/IGF-I) axis is an important stimulator of collagen synthesis in connective tissue, but the effect of chronically altered GH/IGF-I levels on connective tissue of the muscle-tendon unit is not known. We studied three groups of mice; 1) giant...... transgenic mice that expressed bovine GH (bGH) and had high circulating levels of GH and IGF-I, 2) dwarf mice with a disrupted GH receptor gene (GHR-/-) leading to GH resistance and low circulating IGF-I, and 3) a wild-type control group (CTRL). We measured the ultra-structure, collagen content and m...... influenced both morphology and mRNA levels of selected genes in the muscle-tendon unit of mice. Whereas only moderate structural changes were observed with up-regulation of GH/IGF-I axis, disruption of the GH receptor had pronounced effects upon tendon ultra-structure....

  2. Endogenous endothelium-derived relaxing factor opposes hypoxic pulmonary vasoconstriction and supports blood flow to hypoxic alveoli in anesthetized rabbits.

    OpenAIRE

    Sprague, R. S.; Thiemermann, C; Vane, J R

    1992-01-01

    Agents that inhibit nitric oxide synthesis augment hypoxic pulmonary vasoconstriction. In an animal model of unilateral alveolar hypoxia, we investigated the hypothesis that endogenous endothelium-derived relaxing factor/nitric oxide opposes hypoxic pulmonary vasoconstriction and supports blood flow to hypoxic alveoli, resulting in a reduction in arterial oxygen tension (PO2). In pentobarbital-anesthetized rabbits, unilateral alveolar hypoxia was produced by ventilation of one lung with 100% ...

  3. Effects of Chronic Sleep Restriction during Early Adolescence on the Adult Pattern of Connectivity of Mouse Secondary Motor Cortex123

    Science.gov (United States)

    Billeh, Yazan N.; Bernard, Amy; de Vivo, Luisa; Honjoh, Sakiko; Mihalas, Stefan; Ng, Lydia; Koch, Christof

    2016-01-01

    Abstract Cortical circuits mature in stages, from early synaptogenesis and synaptic pruning to late synaptic refinement, resulting in the adult anatomical connection matrix. Because the mature matrix is largely fixed, genetic or environmental factors interfering with its establishment can have irreversible effects. Sleep disruption is rarely considered among those factors, and previous studies have focused on very young animals and the acute effects of sleep deprivation on neuronal morphology and cortical plasticity. Adolescence is a sensitive time for brain remodeling, yet whether chronic sleep restriction (CSR) during adolescence has long-term effects on brain connectivity remains unclear. We used viral-mediated axonal labeling and serial two-photon tomography to measure brain-wide projections from secondary motor cortex (MOs), a high-order area with diffuse projections. For each MOs target, we calculated the projection fraction, a combined measure of passing fibers and axonal terminals normalized for the size of each target. We found no homogeneous differences in MOs projection fraction between mice subjected to 5 days of CSR during early adolescence (P25–P30, ≥50% decrease in daily sleep, n=14) and siblings that slept undisturbed (n=14). Machine learning algorithms, however, classified animals at significantly above chance levels, indicating that differences between the two groups exist, but are subtle and heterogeneous. Thus, sleep disruption in early adolescence may affect adult brain connectivity. However, because our method relies on a global measure of projection density and was not previously used to measure connectivity changes due to behavioral manipulations, definitive conclusions on the long-term structural effects of early CSR require additional experiments. PMID:27351022

  4. Effects of Chronic Sleep Restriction during Early Adolescence on the Adult Pattern of Connectivity of Mouse Secondary Motor Cortex.

    Science.gov (United States)

    Billeh, Yazan N; Rodriguez, Alexander V; Bellesi, Michele; Bernard, Amy; de Vivo, Luisa; Funk, Chadd M; Harris, Julie; Honjoh, Sakiko; Mihalas, Stefan; Ng, Lydia; Koch, Christof; Cirelli, Chiara; Tononi, Giulio

    2016-01-01

    Cortical circuits mature in stages, from early synaptogenesis and synaptic pruning to late synaptic refinement, resulting in the adult anatomical connection matrix. Because the mature matrix is largely fixed, genetic or environmental factors interfering with its establishment can have irreversible effects. Sleep disruption is rarely considered among those factors, and previous studies have focused on very young animals and the acute effects of sleep deprivation on neuronal morphology and cortical plasticity. Adolescence is a sensitive time for brain remodeling, yet whether chronic sleep restriction (CSR) during adolescence has long-term effects on brain connectivity remains unclear. We used viral-mediated axonal labeling and serial two-photon tomography to measure brain-wide projections from secondary motor cortex (MOs), a high-order area with diffuse projections. For each MOs target, we calculated the projection fraction, a combined measure of passing fibers and axonal terminals normalized for the size of each target. We found no homogeneous differences in MOs projection fraction between mice subjected to 5 days of CSR during early adolescence (P25-P30, ≥ 50% decrease in daily sleep, n=14) and siblings that slept undisturbed (n=14). Machine learning algorithms, however, classified animals at significantly above chance levels, indicating that differences between the two groups exist, but are subtle and heterogeneous. Thus, sleep disruption in early adolescence may affect adult brain connectivity. However, because our method relies on a global measure of projection density and was not previously used to measure connectivity changes due to behavioral manipulations, definitive conclusions on the long-term structural effects of early CSR require additional experiments. PMID:27351022

  5. Dendritic cell reprogramming by the hypoxic environment.

    Science.gov (United States)

    Bosco, Maria Carla; Varesio, Luigi

    2012-12-01

    Myeloid dendritic cells (DCs) are professional antigen-presenting cells central to the orchestration of innate and acquired immunity and the maintenance of self-tolerance. The local microenvironment contributes to the regulation of DC development and functions, and deregulated DC responses may result in amplification of inflammation, loss of tolerance, or establishment of immune escape mechanisms. DC generation from monocytic precursors recruited at sites of inflammation, tissue damage, or neoplasia occurs under condition of low partial oxygen pressure (pO(2), hypoxia). We reviewed the literature addressing the phenotypic and functional changes triggered by hypoxia in monocyte-derived immature (i) and mature (m) DCs. The discussion will revolve around in vitro studies of gene expression profile, which give a comprehensive representation of the complexity of response of these cells to low pO(2). The gene expression pattern of hypoxic DC will be discussed to address the question of the relationship with a specific maturation stage. We will summarize data relative to the regulation of the chemotactic network, which points to a role for hypoxia in promoting a migratory phenotype in iDCs and a highly proinflammatory state in mDCs. Current knowledge of the strict regulatory control exerted by hypoxia on the expression of immune-related cell surface receptors will also be addressed, with a particular focus on a newly identified marker of hypoxic DCs endowed with proinflammatory properties. Furthermore, we discuss the literature on the transcription mechanisms underlying hypoxia-regulated gene expression in DCs, which support a major role for the HIF/HRE pathway. Finally, recent advances shedding light on the in vivo influence of the local hypoxic microenvironment on DCs infiltrating the inflamed joints of juvenile idiopathic arthritis patients are outlined. PMID:22901977

  6. Acute Hypoxic Test in Patients with Prediabetes.

    Science.gov (United States)

    Shatylo, Valerii B; Serebrovska, Tatiana V; Gavalko, Anna V; Egorov, Egor; Korkushko, Oleg V

    2016-06-01

    Shatylo, Valerii B., Tetiana V. Serebrovska, Anna V. Gavalko, Egor Egorov, and Oleg V. Korkushko. Acute hypoxic test in patients with prediabetes. High Alt Med Biol. 17:101-107, 2016.-Prediabetes is a state of impaired carbohydrate metabolism when not all of the symptoms required to label a person as diabetic are present, but blood glucose is higher than in healthy subjects. Recent evidence suggests that intermittent hypoxia training (IHT) might provide a cost-effective strategy for improving metabolic functioning. One of the most important aspects of the successful IHT application is individualized approach to hypoxic dose and regimen prescription. To establish the relationships between indices of carbohydrate metabolism and individual resistance to hypoxia, the acute hypoxic test (AHT, breathing gas mixture with 12% O2 during 20 minutes) was performed in 33 healthy volunteers (mean age, 63.0, range, 44-76; fasting plasma glucose (FPG) less than 5.6 mmol/L and 2 hours postoral glucose tolerance test (OGTT) glycemia less than 7.8 mmol/L) and 30 patients with impaired glucose metabolism (mean age, 65.5, range, 44-75; FPG from 5.6 to 6.9 mmol/L and 2 hours post-OGTT glycemia from 7.8 to 11 mmol/L). Negative correlation was found between the SaO2 level at 20th minute AHT and FPG (r = -0.83; p recovery time and less effective functioning of respiratory and cardiovascular systems were also registered in patients with prediabetes showing that their cardiovascular resilience is impaired compared to normoglycemic controls. These patterns of relationship must be considered when assigning the individual modes of IHT. PMID:27213550

  7. Germination under Extreme Hypobaric and Hypoxic Environment

    Science.gov (United States)

    Hashimoto, Hirofumi

    Is the agriculture on Mars without a pressured greenhouse dome possible? In order to inves-tigate a possibility of plant cultivation for the space agriculture on Mars, germination rate for six species of plant, Jute, Chrysanthemum, Komatsuna, Cucumber, Okra, and Eggplant under extreme hypobaric and hypoxic condition was measured. Oxygen partial pressure was 1kPa which was equal to 1/100 of normal earth atmosphere. Seeds of Jute and Cucumber were able to germinate in six species. In the case of Jute, germination rate under the oxygen partial pressure of 1kPa was very high, 70

  8. Gene expression changes after hypoxic preconditioning in rat hepatocytes

    Institute of Scientific and Technical Information of China (English)

    Wei Chen; Jiang-Feng Qiu; Zhi-Qi Zhang; Hai-Feng Luo; Joan Rosello-Catafau; Zhi-Yong Wu

    2006-01-01

    BACKGROUND: Hypoxic preconditioning can protect hepatocytes against hypoxic injury, but its mechanism has not been elucidated. The aim of this study was to proifle gene expression patterns involved in hypoxic preconditioning and probable mechanism at the level of gene expression. METHODS: Hepatocytes were divided into 2 groups:control group and hypoxic preconditioning group. Biotin-labeled cRNA from the control group and the hypoxic preconditioning group was hybridized by oligonucleotide microarray. Genes that were signiifcantly associated with hypoxic preconditioning were ifltered, and validated at the level of transcript expression. RESULTS: Forty-three genes with signiifcantly altered expression patterns were discovered and most of them had not been previously reported. Among these genes, genes encoding superoxide dismutase 2 (SOD2)and interleukin 10 (IL-10) in the hypoxic preconditioning group were conifrmed to be up-regulated with real-time quantitative PCR. CONCLUSIONS:Many cytokines are involved in hypoxic preconditioning and protect hepatocytes from hypoxia-reoxygenation injury, and the increase of oxygen free-radical scavengers and anti-inlfammatory factors may play a key role in this phenomenon. Diverse signal pathways are probably involved.

  9. Hypoxic cell turnover in different solid tumor lines.

    NARCIS (Netherlands)

    Ljungkvist, A.; Bussink, J.; Kaanders, J.H.A.M.; Rijken, P.F.J.W.; Begg, A.C.; Raleigh, J.A.; Kogel, A.J. van der

    2005-01-01

    PURPOSE: Most solid tumors contain hypoxic cells, and the amount of tumor hypoxia has been shown to have a negative impact on the outcome of radiotherapy. The efficacy of combined modality treatments depends both on the sequence and timing of the treatments. Hypoxic cell turnover in tumors may be im

  10. Role of tachykinin 1 and 4 gene-derived neuropeptides and the neurokinin 1 receptor in adjuvant-induced chronic arthritis of the mouse.

    Directory of Open Access Journals (Sweden)

    Eva Borbély

    Full Text Available OBJECTIVE: Substance P, encoded by the Tac1 gene, is involved in neurogenic inflammation and hyperalgesia via neurokinin 1 (NK1 receptor activation. Its non-neuronal counterpart, hemokinin-1, which is derived from the Tac4 gene, is also a potent NK1 agonist. Although hemokinin-1 has been described as a tachykinin of distinct origin and function compared to SP, its role in inflammatory and pain processes has not yet been elucidated in such detail. In this study, we analysed the involvement of tachykinins derived from the Tac1 and Tac4 genes, as well as the NK1 receptor in chronic arthritis of the mouse. METHODS: Complete Freund's Adjuvant was injected intraplantarly and into the tail of Tac1(-/-, Tac4(-/-, Tacr1(-/- (NK1 receptor deficient and Tac1(-/-/Tac4(-/- mice. Paw volume was measured by plethysmometry and mechanosensitivity using dynamic plantar aesthesiometry over a time period of 21 days. Semiquantitative histopathological scoring and ELISA measurement of IL-1β concentrations of the tibiotarsal joints were performed. RESULTS: Mechanical hyperalgesia was significantly reduced from day 11 in Tac4(-/- and Tacr1(-/- animals, while paw swelling was not altered in any strain. Inflammatory histopathological alterations (synovial swelling, leukocyte infiltration, cartilage destruction, bone damage and IL-1β concentration in the joint homogenates were significantly smaller in Tac4(-/- and Tac1(-/-/Tac4(-/- mice. CONCLUSIONS: Hemokinin-1, but not substance P increases inflammation and hyperalgesia in the late phase of adjuvant-induced arthritis. While NK1 receptors mediate its antihyperalgesic actions, the involvement of another receptor in histopathological changes and IL-1β production is suggested.

  11. Mouse chronic social stress increases blood and brain kynurenine pathway activity and fear behaviour: Both effects are reversed by inhibition of indoleamine 2,3-dioxygenase.

    Science.gov (United States)

    Fuertig, René; Azzinnari, Damiano; Bergamini, Giorgio; Cathomas, Flurin; Sigrist, Hannes; Seifritz, Erich; Vavassori, Stefano; Luippold, Andreas; Hengerer, Bastian; Ceci, Angelo; Pryce, Christopher R

    2016-05-01

    Psychosocial stress is a major risk factor for mood and anxiety disorders, in which excessive reactivity to aversive events/stimuli is a major psychopathology. In terms of pathophysiology, immune-inflammation is an important candidate, including high blood and brain levels of metabolites belonging to the kynurenine pathway. Animal models are needed to study causality between psychosocial stress, immune-inflammation and hyper-reactivity to aversive stimuli. The present mouse study investigated effects of psychosocial stress as chronic social defeat (CSD) versus control-handling (CON) on: Pavlovian tone-shock fear conditioning, activation of the kynurenine pathway, and efficacy of a specific inhibitor (IDOInh) of the tryptophan-kynurenine catabolising enzyme indoleamine 2,3-dioxygenase (IDO1), in reversing CSD effects on the kynurenine pathway and fear. CSD led to excessive fear learning and memory, whilst repeated oral escitalopram (antidepressant and anxiolytic) reversed excessive fear memory, indicating predictive validity of the model. CSD led to higher blood levels of TNF-α, IFN-γ, kynurenine (KYN), 3-hydroxykynurenine (3-HK) and kynurenic acid, and higher KYN and 3-HK in amygdala and hippocampus. CSD was without effect on IDO1 gene or protein expression in spleen, ileum and liver, whilst increasing liver TDO2 gene expression. Nonetheless, oral IDOInh reduced blood and brain levels of KYN and 3-HK in CSD mice to CON levels, and we therefore infer that CSD increases IDO1 activity by increasing its post-translational activation. Furthermore, repeated oral IDOInh reversed excessive fear memory in CSD mice to CON levels. IDOInh reversal of CSD-induced hyper-activity in the kynurenine pathway and fear system contributes significantly to the evidence for a causal pathway between psychosocial stress, immune-inflammation and the excessive fearfulness that is a major psychopathology in stress-related neuropsychiatric disorders. PMID:26724575

  12. BL-7010 demonstrates specific binding to gliadin and reduces gluten-associated pathology in a chronic mouse model of gliadin sensitivity.

    Directory of Open Access Journals (Sweden)

    Justin L McCarville

    Full Text Available Celiac disease (CD is an autoimmune disorder in individuals that carry DQ2 or DQ8 MHC class II haplotypes, triggered by the ingestion of gluten. There is no current treatment other than a gluten-free diet (GFD. We have previously shown that the BL-7010 copolymer poly(hydroxyethyl methacrylate-co-styrene sulfonate (P(HEMA-co-SS binds with higher efficiency to gliadin than to other proteins present in the small intestine, ameliorating gliadin-induced pathology in the HLA-HCD4/DQ8 model of gluten sensitivity. The aim of this study was to investigate the efficiency of two batches of BL-7010 to interact with gliadin, essential vitamins and digestive enzymes not previously tested, and to assess the ability of the copolymer to reduce gluten-associated pathology using the NOD-DQ8 mouse model, which exhibits more significant small intestinal damage when challenged with gluten than HCD4/DQ8 mice. In addition, the safety and systemic exposure of BL-7010 was evaluated in vivo (in rats and in vitro (genetic toxicity studies. In vitro binding data showed that BL-7010 interacted with high affinity with gliadin and that BL-7010 had no interaction with the tested vitamins and digestive enzymes. BL-7010 was effective at preventing gluten-induced decreases in villus-to-crypt ratios, intraepithelial lymphocytosis and alterations in paracellular permeability and putative anion transporter-1 mRNA expression in the small intestine. In rats, BL-7010 was well-tolerated and safe following 14 days of daily repeated administration of 3000 mg/kg. BL-7010 did not exhibit any mutagenic effect in the genetic toxicity studies. Using complementary animal models and chronic gluten exposure the results demonstrate that administration of BL-7010 is effective and safe and that it is able to decrease pathology associated with gliadin sensitization warranting the progression to Phase I trials in humans.

  13. Chronic active hepatitis induced by Helicobacter hepaticus in the A/JCr mouse is associated with a Th1 cell-mediated immune response.

    Science.gov (United States)

    Whary, M T; Morgan, T J; Dangler, C A; Gaudes, K J; Taylor, N S; Fox, J G

    1998-07-01

    Helicobacter hepaticus infection in A/JCr mice results in chronic active hepatitis characterized by perivascular, periportal, and parenchymal infiltrates of mononuclear and polymorphonuclear cells. This study examined the development of hepatitis and the immune response of A/JCr mice to H. hepaticus infection. The humoral and cell-mediated T helper immune response was profiled by measuring the postinfection (p.i.) antibody response in serum, feces, and bile and by the production of cytokines and proliferative responses by splenic mononuclear cells to H. hepaticus antigens. Secretory immunoglobulin A (IgA) and systemic IgG2a antibody developed by 4 weeks p.i. and persisted through 12 months. Splenocytes from infected mice proliferated and produced more gamma interferon (IFN-gamma) than interleukin-4 (IL-4) or IL-5 when cultured with H. hepaticus outer membrane proteins. The predominantly IgG2a antibody response in serum and the in vitro production of IFN-gamma in excess of IL-4 or IL-5 are consistent with a Th1 immune response reported in humans and mice infected with Helicobacter pylori and Helicobacter felis, respectively. Mice infected with H. hepaticus developed progressively severe perivascular, periportal, and hepatic parenchymal lesions consisting of lymphohistiocytic and plasmacytic cellular infiltrates. In addition, transmural typhlitis was observed at 12 months p.i. The characterization of a cell-mediated Th1 immune response to H. hepaticus infection in the A/JCr mouse should prove valuable as a model for experimental regimens which manipulate the host response to Helicobacter.

  14. Biomarkers of Hypoxic Ischemic Encephalopathy in Newborns

    Directory of Open Access Journals (Sweden)

    Martha V. Douglas-Escobar

    2012-11-01

    Full Text Available As neonatal intensive care has evolved, the focus has shifted from improving mortality alone to an effort to improve both mortality and morbidity. The most frequent source of neonatal brain injury occurs as a result of hypoxic-ischemic injury. Hypoxic-ischemic injury occurs in about 2 of 1,000 full-term infants and severe injured infants will have lifetime disabilities and neurodevelopmental delays. Most recently, remarkable efforts toward neuroprotection have been started with the advent of therapeutic hypothermia and a key step in the evolution of neonatal neuroprotection is the discovery of biomarkers that enable the clinician-scientist to screen infants for brain injury, monitor progression of disease, identify injured brain regions, and assess efficacy of neuroprotective clinical trials. Lastly, biomarkers offer great hope identifying when an injury occurred shedding light on the potential pathophysiology and the most effective therapy. In this article, we will review biomarkers of HIE including S100b, neuron specific enolase, umbilical cord IL-6, CK-BB, GFAP, myelin basic protein, UCHL-1, and pNF-H. We hope to contribute to the awareness, validation and clinical use of established as well as novel neonatal brain injury biomarkers.

  15. Early cerebral hemodynamic, metabolic and histological changes in hypoxic-ischemic fetal lambs during postnatal life

    Directory of Open Access Journals (Sweden)

    Carmen eRey-Santano

    2011-09-01

    Full Text Available The hemodynamic, metabolic and biochemical changes produce during transition from fetal to neonatal life could be aggravated if asphyctic event occur during fetal life. The aim of the study was to examine the regional cerebral blood flow (RCBF, histological changes, and cerebral brain metabolism in preterm lambs, and to analyze the role of oxidative stress for the first hours of postnatal life following severe fetal asphyxia. 18 chronically instrumented fetal lambs were assigned to: hypoxic-ischemic group, following fetal asphyxia animals were delivered and maintained on intermittent-positive-pressure-ventilation for 3 hours, and non-injured animals that were managed similarly to the previous group and used as control group. During hypoxic-ischemic insult, injured group developed acidosis, hypoxia, hypercapnia, latacidaemia and tachycardia in comparison to control group, without hypotension. Intermittent-positive-pressure-ventilation transiently improved gas exchange and cardiovascular parameters. After HI injury and during ventilation-support, the increased RCBF in inner zones was maintained for hypoxic-ischemic group, but cortical flow did not exhibit differences compared to the control group. Also, the increase of TUNEL positive cells (apoptosis and antioxidant enzymes, and decrease of ATP reserves was significantly higher in the brain regions where the RCBF were not increased.In conclusion, early metabolic, histological and hemodynamic changes involved in brain damage have been intensively investigated and reported in premature asphyctic lambs for the first 3 hours of postnatal life. Those changes have been described in human neonates, so our model could be useful to test the security and the effectiveness of different neuroprotective or ventilatory strategies when are applied in the first hours after fetal hypoxic-ischemic injury.

  16. Hepatocytes Determine the Hypoxic Microenvironment and Radiosensitivity of Colorectal Cancer Cells Through Production of Nitric Oxide That Targets Mitochondrial Respiration

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Heng; Verovski, Valeri N.; Leonard, Wim; Law, Ka Lun; Vermeersch, Marieke; Storme, Guy; Van den Berge, Dirk; Gevaert, Thierry; Sermeus, Alexandra [Department of Radiotherapy, Universitair Ziekenhuis Brussel, Vrije Universiteit Brussel, Brussels (Belgium); De Ridder, Mark, E-mail: mark.deridder@uzbrussel.be [Department of Radiotherapy, Universitair Ziekenhuis Brussel, Vrije Universiteit Brussel, Brussels (Belgium)

    2013-03-01

    Purpose: To determine whether host hepatocytes may reverse hypoxic radioresistance through nitric oxide (NO)-induced oxygen sparing, in a model relevant to colorectal cancer (CRC) liver metastases. Methods and Materials: Hepatocytes and a panel of CRC cells were incubated in a tissue-mimetic coculture system with diffusion-limited oxygenation, and oxygen levels were monitored by an oxygen-sensing fluorescence probe. To activate endogenous NO production, cocultures were exposed to a cytokine mixture, and the expression of inducible nitric oxide synthase was analyzed by reverse transcription–polymerase chain reaction, Western blotting, and NO/nitrite production. The mitochondrial targets of NO were examined by enzymatic activity. To assess hypoxic radioresponse, cocultures were irradiated and reseeded for colonies. Results: Resting hepatocytes consumed 10-40 times more oxygen than mouse CT26 and human DLD-1, HT29, HCT116, and SW480 CRC cells, and thus seemed to be the major effectors of hypoxic conditioning. As a result, hepatocytes caused uniform radioprotection of tumor cells at a 1:1 ratio. Conversely, NO-producing hepatocytes radiosensitized all CRC cell lines more than 1.5-fold, similar to the effect of selective mitochondrial inhibitors. The radiosensitizing effect was associated with a respiratory self-arrest of hepatocytes at the level of aconitase and complex II, which resulted in profound reoxygenation of tumor cells through oxygen sparing. Nitric oxide–producing hepatocytes were at least 10 times more active than NO-producing macrophages to reverse hypoxia-induced radioresistance. Conclusions: Hepatocytes were the major determinants of the hypoxic microenvironment and radioresponse of CRC cells in our model of metabolic hypoxia. We provide evidence that reoxygenation and radiosensitization of hypoxic CRC cells can be achieved through oxygen sparing induced by endogenous NO production in host hepatocytes.

  17. Effects of Yulangsan polysaccharide on monoamine neurotransmitters, adenylate cyclase activity and brain-derived neurotrophic factor expression in a mouse model of depression induced by unpredictable chronic mild stress

    Institute of Scientific and Technical Information of China (English)

    Shuang Liang; Renbin Huang; Xing Lin; Jianchun Huang; Zhongshi Huang; Huagang Liu

    2012-01-01

    The present study established a mouse model of depression induced by unpredictable chronic mild stress. The model mice were treated with Yulangsan polysaccharide (YLSPS; 150, 300 and 600 mg/kg) for 21 days, and compared with fluoxetine-treated and normal control groups. Enzyme-linked immunosorbent assay, radioimmunity and immunohistochemical staining showed that following treatment with YLSPS (300 and 600 mg/kg), monoamine neurotransmitter levels, prefrontal cortex adenylate cyclase activity and hippocampal brain-derived neurotrophic factor expression were significantly elevated, and depression-like behaviors were improved. Open-field and novelty-suppressed feeding tests showed that mouse activity levels were increased and feeding latency was shortened following treatment. Our results indicate that YLSPS inhibits depression by upregulating monoamine neurotransmitters, prefrontal cortex adenylate cyclase activity and hippocampal brain-derived neurotrophic factor expression.

  18. Heart rate response to hypoxic exercise

    DEFF Research Database (Denmark)

    Lundby, C; Møller, P; Kanstrup, I L;

    2001-01-01

    This study examined the effects of dopamine D(2)-receptor blockade on the early decrease in maximal heart rate at high altitude (4559 m). We also attempted to clarify the time-dependent component of this reduction and the extent to which it is reversed by oxygen breathing. Twelve subjects performed...... progressively decreased the maximal heart rate from day 1 and onwards; also, hypoxia by itself increased plasma noradrenaline levels after maximal exercise. Domperidone further increased maximal noradrenaline concentrations, but had no effect on maximal heart rate. On each study day at altitude, oxygen...... breathing completely reversed the decrease in maximal heart rate to values not different from those at sea level. In conclusion, dopamine D(2)-receptor blockade with domperidone demonstrates that hypoxic exercise in humans activates D(2)-receptors, resulting in a decrease in circulating levels...

  19. Placenta growth factor and vascular endothelial growth factor B expression in the hypoxic lung

    Directory of Open Access Journals (Sweden)

    McLoughlin Paul

    2011-01-01

    Full Text Available Abstract Background Chronic alveolar hypoxia, due to residence at high altitude or chronic obstructive lung diseases, leads to pulmonary hypertension, which may be further complicated by right heart failure, increasing morbidity and mortality. In the non-diseased lung, angiogenesis occurs in chronic hypoxia and may act in a protective, adaptive manner. To date, little is known about the behaviour of individual vascular endothelial growth factor (VEGF family ligands in hypoxia-induced pulmonary angiogenesis. The aim of this study was to examine the expression of placenta growth factor (PlGF and VEGFB during the development of hypoxic pulmonary angiogenesis and their functional effects on the pulmonary endothelium. Methods Male Sprague Dawley rats were exposed to conditions of normoxia (21% O2 or hypoxia (10% O2 for 1-21 days. Stereological analysis of vascular structure, real-time PCR analysis of vascular endothelial growth factor A (VEGFA, VEGFB, placenta growth factor (PlGF, VEGF receptor 1 (VEGFR1 and VEGFR2, immunohistochemistry and western blots were completed. The effects of VEGF ligands on human pulmonary microvascular endothelial cells were determined using a wound-healing assay. Results Typical vascular remodelling and angiogenesis were observed in the hypoxic lung. PlGF and VEGFB mRNA expression were significantly increased in the hypoxic lung. Immunohistochemical analysis showed reduced expression of VEGFB protein in hypoxia although PlGF protein was unchanged. The expression of VEGFA mRNA and protein was unchanged. In vitro PlGF at high concentration mimicked the wound-healing actions of VEGFA on pulmonary microvascular endothelial monolayers. Low concentrations of PlGF potentiated the wound-healing actions of VEGFA while higher concentrations of PlGF were without this effect. VEGFB inhibited the wound-healing actions of VEGFA while VEGFB and PlGF together were mutually antagonistic. Conclusions VEGFB and PlGF can either inhibit or

  20. Placenta growth factor and vascular endothelial growth factor B expression in the hypoxic lung

    LENUS (Irish Health Repository)

    Sands, Michelle

    2011-01-25

    Abstract Background Chronic alveolar hypoxia, due to residence at high altitude or chronic obstructive lung diseases, leads to pulmonary hypertension, which may be further complicated by right heart failure, increasing morbidity and mortality. In the non-diseased lung, angiogenesis occurs in chronic hypoxia and may act in a protective, adaptive manner. To date, little is known about the behaviour of individual vascular endothelial growth factor (VEGF) family ligands in hypoxia-induced pulmonary angiogenesis. The aim of this study was to examine the expression of placenta growth factor (PlGF) and VEGFB during the development of hypoxic pulmonary angiogenesis and their functional effects on the pulmonary endothelium. Methods Male Sprague Dawley rats were exposed to conditions of normoxia (21% O2) or hypoxia (10% O2) for 1-21 days. Stereological analysis of vascular structure, real-time PCR analysis of vascular endothelial growth factor A (VEGFA), VEGFB, placenta growth factor (PlGF), VEGF receptor 1 (VEGFR1) and VEGFR2, immunohistochemistry and western blots were completed. The effects of VEGF ligands on human pulmonary microvascular endothelial cells were determined using a wound-healing assay. Results Typical vascular remodelling and angiogenesis were observed in the hypoxic lung. PlGF and VEGFB mRNA expression were significantly increased in the hypoxic lung. Immunohistochemical analysis showed reduced expression of VEGFB protein in hypoxia although PlGF protein was unchanged. The expression of VEGFA mRNA and protein was unchanged. In vitro PlGF at high concentration mimicked the wound-healing actions of VEGFA on pulmonary microvascular endothelial monolayers. Low concentrations of PlGF potentiated the wound-healing actions of VEGFA while higher concentrations of PlGF were without this effect. VEGFB inhibited the wound-healing actions of VEGFA while VEGFB and PlGF together were mutually antagonistic. Conclusions VEGFB and PlGF can either inhibit or potentiate the

  1. Field study of cyclic hypoxic effects on gene expression in grass shrimp hepatopancreas.

    Science.gov (United States)

    Li, Tiandao; Brouwer, Marius

    2013-12-01

    Grass shrimp, Palaemonetes pugio, are widely used for ecological and toxicological research. They commonly experience cyclic hypoxia in their natural habitats. The response of grass shrimp to laboratory-controlled cyclic hypoxia has been studied in detail, but little is known about how field acclimatized grass shrimp regulate the gene expression and response to cyclic hypoxia. In this study we examined morphometric parameters, relative fecundity and gene expression of grass shrimp collected from two areas in Weeks Bay (Mobile, Alabama). One is a traditionally normoxic location (WBM), and the other is a traditionally cyclic hypoxic location (WC). In the week preceding grass shrimp collection dissolved oxygen (DO) at the field sites was measured continuously. DO was shrimp were significantly greater than weight and length of WC shrimp. WBM shrimp had more eggs than WC shrimp, but the difference was not significant. Shrimp from WC had a significant higher number of parasites than those from WBM. A cDNA microarray was utilized to investigate the changes in gene expression in grass shrimp hepatopancreas. Five genes, previously identified as hypoxia/cyclic hypoxia-responsive genes in laboratory exposure studies, were significantly up-regulated in WC shrimp relative to WBM. A total of 5 genes were significantly down-regulated in the field study. Only one of those genes, vitellogenin, has been previously found in chronic and cyclic hypoxic studies. Up and down-regulation of 7 selected genes was confirmed by qPCR. The overall pattern of gene expression in wild shrimp from cyclic DO sites in Weeks Bay showed only weak correlations with gene expression in shrimp from chronic and cyclic hypoxic laboratory studies. It appears therefore that transcriptome profiles of laboratory acclimated animals are of limited utility for understanding responses in field acclimatized animals that are exposed to a broader array of environmental variables.

  2. LET-painting increases tumour control probability in hypoxic tumours.

    Science.gov (United States)

    Bassler, Niels; Toftegaard, Jakob; Lühr, Armin; Sørensen, Brita Singers; Scifoni, Emanuele; Krämer, Michael; Jäkel, Oliver; Mortensen, Lise Saksø; Overgaard, Jens; Petersen, Jørgen B

    2014-01-01

    LET-painting was suggested as a method to overcome tumour hypoxia. In vitro experiments have demonstrated a well-established relationship between the oxygen enhancement ratio (OER) and linear energy transfer (LET), where OER approaches unity for high-LET values. However, high-LET radiation also increases the risk for side effects in normal tissue. LET-painting attempts to restrict high-LET radiation to compartments that are found to be hypoxic, while applying lower LET radiation to normoxic tissues. Methods. Carbon-12 and oxygen-16 ion treatment plans with four fields and with homogeneous dose in the target volume, are applied on an oropharyngeal cancer case with an identified hypoxic entity within the tumour. The target dose is optimised to achieve a tumour control probability (TCP) of 95% when assuming a fully normoxic tissue. Using the same primary particle energy fluence needed for this plan, TCP is recalculated for three cases assuming hypoxia: first, redistributing LET to match the hypoxic structure (LET-painting). Second, plans are recalculated for varying hypoxic tumour volume in order to investigate the threshold volume where TCP can be established. Finally, a slight dose boost (5-20%) is additionally allowed in the hypoxic subvolume to assess its impact on TCP. Results. LET-painting with carbon-12 ions can only achieve tumour control for hypoxic subvolumes smaller than 0.5 cm(3). Using oxygen-16 ions, tumour control can be achieved for tumours with hypoxic subvolumes of up to 1 or 2 cm(3). Tumour control can be achieved for tumours with even larger hypoxic subvolumes, if a slight dose boost is allowed in combination with LET-painting. Conclusion. Our findings clearly indicate that a substantial increase in tumour control can be achieved when applying the LET-painting concept using oxygen-16 ions on hypoxic tumours, ideally with a slight dose boost.

  3. Hypoxic sensitizers: radiobiological studies at the cellular level

    International Nuclear Information System (INIS)

    The nitroimidazoles have been found to selectively sensitize hypoxic cells to the effects of irradiation. The latest in this family of drugs is RO-07-0582, which is able to mimic 80 percent of the oxygen effect at a concentration of 5 mM by modifying the sensitivity of hypoxic cells to single doses of gamma rays; however, it is not a substitution for oxygen in promoting the repair of sublethal radiation damage between split doses. Studies show that it is a powerful cytotoxic agent as well and selectively operates against hypoxic cells. (auth)

  4. Body Function of Rowers before and after Hypoxic Pre-conditioning and Chronic Sub-Altitude Training%低氧预适应结合长时间亚高原训练前后男子赛艇运动员身体机能分析

    Institute of Scientific and Technical Information of China (English)

    王刚; 高炳宏; 高欢

    2013-01-01

    目的:分析低氧预适应结合亚高原训练前后男子赛艇运动员身体机能状态的变化.方法:16名优秀男子赛艇运动员为对象,先进行10天HiLo低氧训练,模拟海拔高度为1200~1500 m.再于海拔1500 m进行8周亚高原训练.分别于低氧训练前和亚高原训练前、中、后不同时段测定分析运动员身体机能状态,测试指标包括:氧转运系统指标(Hb、RBC)、内分泌系统指标(T、C、T/C、EPO)、免疫系统指标(WBC、IgA、IgM、IgG)以及CK和BU.结果:与低氧训练前相比,1)EPO在低氧训练后和高原训练第3天出现两个峰值,升高幅度分别为26.27%和26.60%(P<0.01).Hb在低氧后显著下降(P<0.01),高原训练第3天,第1、3、7周,下高原后第2、3周显著升高(P<0.05或P<0.01);2)白细胞在实验期间升高(P<0.01),IgA和IgG无显著变化(P>0.05),IgM在低氧训练后、高原训练第3周、下高原后第2周(P<0.01,P<0.05,P<0.05)显著升高;3)低氧训练后血清睾酮下降(P>0.05),高原训练第3天显著升高(P<0.05),血清皮质醇在高原训练第3周(P<0.01)、第5周(P<0.05)显著下降,T/C在高原训练第3天和第3、5周显著升高(P<0.05).结论:低氧预适应干预加快了运动员高原适应;10天低氧预适应结合8周亚高原训练对运动员机能状态产生良好影响,运动员未出现过度疲劳,血液载氧能力提高,免疫能力未见大幅下降.%Purpose To explore the effect of the hypoxic pre-conditioning before sub-altitude training on the body function of rowers.Methods 16 male rowers were selected to complete 10-day training at simulated altitude of 1200 m to 1500 m,followed by 8-week sub-altitude training at the altitude of 1500 m.The levels of EPO,HB,WBC,IgA,IgG and IgM,and serum testosterone (T) and cortisol (C) were tested before hypoxic pre-conditioning and at the different periods of sub-altitude training.Results As compared with before hypoxia,(1)The peak EPO values appeared

  5. PI3K/Akt contributes to increased expression of Toll-like receptor 4 in macrophages exposed to hypoxic stress

    Energy Technology Data Exchange (ETDEWEB)

    Kim, So Young; Jeong, Eunshil; Joung, Sun Myung [School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju 500-712 (Korea, Republic of); Lee, Joo Young, E-mail: joolee@catholic.ac.kr [School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju 500-712 (Korea, Republic of); College of Pharmacy, The Catholic University of Korea, Bucheon 420-743 (Korea, Republic of)

    2012-03-16

    Highlights: Black-Right-Pointing-Pointer Hypoxic stress-induced TLR4 expression is mediated by PI3K/Akt in macrophages. Black-Right-Pointing-Pointer PI3K/Akt regulated HIF-1 activation leading to TLR4 expression. Black-Right-Pointing-Pointer p38 mitogen-activated protein kinase was not involved in TLR4 expression by hypoxic stress. Black-Right-Pointing-Pointer Sulforaphane suppressed hypoxia-mediated TLR4 expression by inhibiting PI3K/Akt. -- Abstract: Toll-like receptors (TLRs) play critical roles in triggering immune and inflammatory responses by detecting invading microbial pathogens and endogenous danger signals. Increased expression of TLR4 is implicated in aggravated inflammatory symptoms in ischemic tissue injury and chronic diseases. Results from our previous study showed that TLR4 expression was upregulated by hypoxic stress mediated by hypoxia-inducible factor-1 (HIF-1) at a transcriptional level in macrophages. In this study, we further investigated the upstream signaling pathway that contributed to the increase of TLR4 expression by hypoxic stress. Either treatment with pharmacological inhibitors of PI3K and Akt or knockdown of Akt expression by siRNA blocked the increase of TLR4 mRNA and protein levels in macrophages exposed to hypoxia and CoCl{sub 2}. Phosphorylation of Akt by hypoxic stress preceded nuclear accumulation of HIF-1{alpha}. A PI3K inhibitor (LY294002) attenuated CoCl{sub 2}-induced nuclear accumulation and transcriptional activation of HIF-1{alpha}. In addition, HIF-1{alpha}-mediated upregulation of TLR4 expression was blocked by LY294002. Furthermore, sulforaphane suppressed hypoxia- and CoCl{sub 2}-induced upregulation of TLR4 mRNA and protein by inhibiting PI3K/Akt activation and the subsequent nuclear accumulation and transcriptional activation of HIF-1{alpha}. However, p38 was not involved in HIF-1{alpha} activation and TLR4 expression induced by hypoxic stress in macrophages. Collectively, our results demonstrate that PI3K

  6. Neuroprotective effects of volume-regulated anion channel blocker DCPIB on neonatal hypoxic-ischemic injury

    Institute of Scientific and Technical Information of China (English)

    Ammar ALIBRAHIM; Li-yan ZHAO; Christine You-jin BAE; Andrew BARSZCZYK; Christopher LF SUN; Guan-lei WANG; Hong-shuo SUN

    2013-01-01

    Aim:To evaluate the role of swelling-induced activation of volume-regulated anion channels (VRACs) in a neonatal hypoxic-ischemic injury model using the selective VRAC blocker 4-(2-butyl-6,7-dichloro-2-cyclopentyl-indan-1-on5-yl) oxobutyric acid (DCPIB).Methods:Cerebral hypoxic-ischemic injury was induced in 7-day-old mouse pups with Rice-Vannucci method.Prior to the onset of ischemia,the animals were ip administered DCPIB (10 mg/kg).The animals were sacrificed 24 h afterwards,coronal sections of the brains were cut and the areas of infarct were examined using TTC staining and an image-analysis system.Cultured PC12 cells were subjected to oxygen-glucose deprivation (OGD) for 4 h.The cellular viability was assessed using Cell Counting Kit 8.Intracellular chloride concentration [Clˉ]i was measured using 6-methoxy-N-ethylquinolinium iodide.Results:DCPIB-treated mice showed a significant reduction in hemispheric corrected infarct volume (26.65%+2.23%) compared to that in vehicle-treated mice (45.52%+1.45%,P<O.O01).DCPIB-treated mice also showed better functional recovery as they were more active than vehicle-treated mice at 4 and 24 h post injury.In cultured PC12 cells,DCPIB (10 μmol/L) significantly reduced OGD-induced cell death.Moreover,DCPIB (20 μmol/L) blocked hypotonic-induced decrease in [Clˉ]i in PC12 cells of both control and OGD groups.Conclusion:The results further support the pathophysiological role of VRACs in ischemic brain injury,and suggest DCPIB as a potential,easily administrable agent targeting VRACs in the context of perinatal and neonatal hypoxic-ischemic brain injury.

  7. A case of hypoxic encephalopathy with delayed exacerbation

    Directory of Open Access Journals (Sweden)

    Takeshi Hayashi

    2008-10-01

    Full Text Available Takeshi Hayashi, Kimihiko HattoriDepartment of Neurology, Fuji Heavy Industries Health Insurance Corporation, Ota General Hospital, Ota, Gunma, JapanAbstract: Most patients contract hypoxic encephalopathy after suffering a cardiac arrest. They usually endure severe neurological sequelae and the temporal profile of the disease progression remains unclear. This case study shows how the effects of hypoxic encephalopathy continue to progress for several years after the initial event. Up to eight years after the hypoxic insult, the patient’s intellect steadily deteriorated, and brain atrophy progressed. As the hypoxic insult on the brain is only transient, the neurological disability seems not to be exacerbated for years. However, our case indicates that this disorder may have a long progression.Keywords: dementia, encephalopathy, hypoxia, MRI

  8. Outcome Prediction Rule for Neonatal Hypoxic-Ischemic Encephalopathy

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2006-08-01

    Full Text Available A prognostic model for term infants with postasphyxial hypoxic-ischemic encephalopathy (HIE based on clinical and laboratory predictors available at age 4 hours was developed at Mount Sinai Hospital and Hospital for Sick Children, Toronto, Ontario.

  9. Hypoxic enhancement of exosome release by breast cancer cells

    Directory of Open Access Journals (Sweden)

    King Hamish W

    2012-09-01

    Full Text Available Abstract Background Exosomes are nanovesicles secreted by tumour cells which have roles in paracrine signalling during tumour progression, including tumour-stromal interactions, activation of proliferative pathways and bestowing immunosuppression. Hypoxia is an important feature of solid tumours which promotes tumour progression, angiogenesis and metastasis, potentially through exosome-mediated signalling. Methods Breast cancer cell lines were cultured under either moderate (1% O2 or severe (0.1% O2 hypoxia. Exosomes were isolated from conditioned media and quantitated by nanoparticle tracking analysis (NTA and immunoblotting for the exosomal protein CD63 in order to assess the impact of hypoxia on exosome release. Hypoxic exosome fractions were assayed for miR-210 by real-time reverse transcription polymerase chain reaction and normalised to exogenous and endogenous control genes. Statistical significance was determined using the Student T test with a P value of  Results Exposure of three different breast cancer cell lines to moderate (1% O2 and severe (0.1% O2 hypoxia resulted in significant increases in the number of exosomes present in the conditioned media as determined by NTA and CD63 immunoblotting. Activation of hypoxic signalling by dimethyloxalylglycine, a hypoxia-inducible factor (HIF hydroxylase inhibitor, resulted in significant increase in exosome release. Transfection of cells with HIF-1α siRNA prior to hypoxic exposure prevented the enhancement of exosome release by hypoxia. The hypoxically regulated miR-210 was identified to be present at elevated levels in hypoxic exosome fractions. Conclusions These data provide evidence that hypoxia promotes the release of exosomes by breast cancer cells, and that this hypoxic response may be mediated by HIF-1α. Given an emerging role for tumour cell-derived exosomes in tumour progression, this has significant implications for understanding the hypoxic tumour phenotype, whereby hypoxic

  10. Marine Natural Products as Inhibitors of Hypoxic Signaling in Tumors

    OpenAIRE

    Nagle, Dale G.; Zhou, Yu-Dong

    2009-01-01

    Marine natural products have become a major source of new chemical entities in the discovery of potential anticancer agents that potently suppress various antitumor molecular targets. As a consequence of insufficient vascularization, hypoxic regions form within rapidly growing solid tumor masses. Specific alterations of gene expression in these hypoxic tumor cells help facilitate the survival and metastatic spread of solid tumors. The transcriptional response to cellular hypoxia is primarily ...

  11. Hypoxic-Ischemic Neonatal Encephalopathy: Animal Experiments for Neuroprotective Therapies

    OpenAIRE

    Hiroshi Sameshima; Tsuyomu Ikenoue

    2013-01-01

    Hypoxic-ischemic neonatal encephalopathy and ensuing brain damage is still an important problem in modern perinatal medicine. In this paper, we would like to share some of the results of our recent studies on neuroprotective therapies in animal experiments, as well as some literature reviews. From the basic animal studies, we have now obtained some possible candidates for therapeutic measures against hypoxic-ischemic neonatal encephalopathy. For example, they are hypothermia, rehabilitation, ...

  12. Hypothermia for Hypoxic Ischemic Encephalopathy in Infants ≥ 36 weeks

    OpenAIRE

    Higgins, Rosemary D.; Shankaran, Seetha

    2009-01-01

    Hypoxic ischemic encephalopathy is a serious condition affecting infants which can result in death and disability. This is a summary of pathogenesis of HIE, animal studies of cooling for hypoxic and ischemic models, human hypothermia trials, and the American Academy of Pediatrics publication on hypothermia for HIE. Hypothermia for neonatal HIE is continuing to evolve as a therapy. Studies, gaps in knowledge and opportunities for research are presented herein.

  13. Hypoxic enhancement of exosome release by breast cancer cells

    International Nuclear Information System (INIS)

    Exosomes are nanovesicles secreted by tumour cells which have roles in paracrine signalling during tumour progression, including tumour-stromal interactions, activation of proliferative pathways and bestowing immunosuppression. Hypoxia is an important feature of solid tumours which promotes tumour progression, angiogenesis and metastasis, potentially through exosome-mediated signalling. Breast cancer cell lines were cultured under either moderate (1% O2) or severe (0.1% O2) hypoxia. Exosomes were isolated from conditioned media and quantitated by nanoparticle tracking analysis (NTA) and immunoblotting for the exosomal protein CD63 in order to assess the impact of hypoxia on exosome release. Hypoxic exosome fractions were assayed for miR-210 by real-time reverse transcription polymerase chain reaction and normalised to exogenous and endogenous control genes. Statistical significance was determined using the Student T test with a P value of < 0.05 considered significant. Exposure of three different breast cancer cell lines to moderate (1% O2) and severe (0.1% O2) hypoxia resulted in significant increases in the number of exosomes present in the conditioned media as determined by NTA and CD63 immunoblotting. Activation of hypoxic signalling by dimethyloxalylglycine, a hypoxia-inducible factor (HIF) hydroxylase inhibitor, resulted in significant increase in exosome release. Transfection of cells with HIF-1α siRNA prior to hypoxic exposure prevented the enhancement of exosome release by hypoxia. The hypoxically regulated miR-210 was identified to be present at elevated levels in hypoxic exosome fractions. These data provide evidence that hypoxia promotes the release of exosomes by breast cancer cells, and that this hypoxic response may be mediated by HIF-1α. Given an emerging role for tumour cell-derived exosomes in tumour progression, this has significant implications for understanding the hypoxic tumour phenotype, whereby hypoxic cancer cells may release more

  14. Liposomal doxorubicin improves radiotherapy response in hypoxic prostate cancer xenografts

    International Nuclear Information System (INIS)

    Tumor vasculature frequently fails to supply sufficient levels of oxygen to tumor tissue resulting in radioresistant hypoxic tumors. To improve therapeutic outcome radiotherapy (RT) may be combined with cytotoxic agents. In this study we have investigated the combination of RT with the cytotoxic agent doxorubicin (DXR) encapsulated in pegylated liposomes (PL-DXR). The PL-DXR formulation Caelyx® was administered to male mice bearing human, androgen-sensitive CWR22 prostate carcinoma xenografts in a dose of 3.5 mg DXR/kg, in combination with RT (2 Gy/day × 5 days) performed under normoxic and hypoxic conditions. Hypoxic RT was achieved by experimentally inducing tumor hypoxia by clamping the tumor-bearing leg five minutes prior to and during RT. Treatment response evaluation consisted of tumor volume measurements and dynamic contrast-enhanced magnetic resonance imaging (DCE MRI) with subsequent pharmacokinetic analysis using the Brix model. Imaging was performed pre-treatment (baseline) and 8 days later. Further, hypoxic fractions were determined by pimonidazole immunohistochemistry of excised tumor tissue. As expected, the therapeutic effect of RT was significantly less effective under hypoxic than normoxic conditions. However, concomitant administration of PL-DXR significantly improved the therapeutic outcome following RT in hypoxic tumors. Further, the pharmacokinetic DCE MRI parameters and hypoxic fractions suggest PL-DXR to induce growth-inhibitory effects without interfering with tumor vascular functions. We found that DXR encapsulated in liposomes improved the therapeutic effect of RT under hypoxic conditions without affecting vascular functions. Thus, we propose that for cytotoxic agents affecting tumor vascular functions liposomes may be a promising drug delivery technology for use in chemoradiotherapy

  15. Therapeutic attack of hypoxic cells of solid tumors: presidential address.

    Science.gov (United States)

    Sartorelli, A C

    1988-02-15

    Hypoxic cells of solid tumors are relatively resistant to therapeutic assault. Studies have demonstrated that oxygen-deficient tumor cells exist in an environment conducive to reductive reactions making hypoxic cells particularly sensitive to bioreductive alkylating agents. Mitomycin C, the prototype bioreductive alkylating agent available for clinical use, is capable of preferentially killing oxygen-deficient cells both in vitro and in vivo. This phenomenon is at least in part the result of differences in the uptake and metabolism of mitomycin C by hypoxic and oxygenated tumor cells, with the ultimate critical lesion being the cross-linking of DNA by the mitomycin antibiotic. The combination of mitomycin C with X-irradiation, to attack hypoxic and oxygenated tumor cell populations, respectively, has led to enhanced antitumor effects in mice bearing solid tumor implants and in patients with cancer of the head and neck. More efficacious kill of hypoxic tumor cells may be possible by the use of dicoumarol in combination with mitomycin or by the use of the related antibiotic porfiromycin. The findings support the use of an agent with specificity for hypoxic tumor cells in potentially curative regimens for solid tumors. PMID:3123053

  16. Pulmonary hypoxic vasoconstriction: how strong? How fast?

    Science.gov (United States)

    Sheehan, D. W.; Klocke, R. A.; Farhi, L. E.

    1992-01-01

    We have developed a minimally invasive technique for studying regional blood flow in conscious sheep, bypassing the complications of open-chest surgery, flow probes and tracer infusion. We quantitate regional perfusion continuously on the basis of regional clearance of methane (methane is produced in the sheep rumen, enters the circulation and is eliminated nearly completely (greater than 95%) in the lung). Tracheal intubation with a dual-lumen catheter isolates the gas exchange of the right apical lobe (RAL; less than 15% of the lung) from that of the remainder of the lung, which serves as a control (CL). We measure RAL and CL methane elimination by entraining expirates in constant flows, sampled continuously for methane. Results obtained with this technique and from regional oxygen uptake are in excellent agreement. We have found that hypoxic vasoconstriction is far more potent and stable during eucapnic hypoxia than during hypocapnic hypoxia. The time course of the vasoconstriction suggests that many of the data in the literature may have been obtained prior to steady state.

  17. Hypoxic Hepatitis: A Review and Clinical Update

    Science.gov (United States)

    Waseem, Najeff; Chen, Po-Hung

    2016-01-01

    Abstract Hypoxic hepatitis (HH), also known as ischemic hepatitis or shock liver, is characterized by a massive, rapid rise in serum aminotransferases resulting from reduced oxygen delivery to the liver. The most common predisposing condition is cardiac failure, followed by circulatory failure as occurs in septic shock and respiratory failure. HH does, however, occur in the absence of a documented hypotensive event or shock state in 50% of patients. In intensive care units, the incidence of HH is near 2.5%, but has been reported as high as 10% in some studies. The pathophysiology is multifactorial, but often involves hepatic congestion from right heart failure along with reduced hepatic blood flow, total body hypoxemia, reduced oxygen uptake by hepatocytes or reperfusion injury following ischemia. The diagnosis is primarily clinical, and typically does not require liver biopsy. The definitive treatment of HH involves correction of the underlying disease state, but successful management includes monitoring for the potential complications such as hypoglycemia, hyperglycemia, hyperammonemia and hepatopulmonary syndrome. Prognosis of HH remains poor, especially for cases in which there was a delay in diagnosis. The in-hospital mortality rate is >50%, and the most frequent cause of death is the predisposing condition and not the liver injury itself. PMID:27777895

  18. Mass Law Predicts Hyperbolic Hypoxic Ventilatory Response

    Science.gov (United States)

    Severinghaus, John W.

    The hyperbolic hypoxic ventilatory response vs PaO2, HVRp, is interpreted as relecting a mass hyperbolic relationship of cytochrome PcO2 to cytochrome potential Ec, offset 32 torr by the constant diffusion gradient between arterial blood and cytochrome in CB at its constant metabolic rate dot VO_2 . Ec is taken to be a linear function of redox reduction and CB ventilatory drive. As Ec rises in hypoxia, the absolute potentials of each step in the citric acid cycle rises equally while the potential drop across each step remains constant because flux rate remains constant. A hypothetic HVRs ( dot VE vs SaO2) response curve computed from these assumptions is strikingly non linear. A hypothetic HVRp calculated from an assumed linear HVRs cannot be fit to the observed hyperbolic increase of ventilation in response to isocapnic hypoxia at PO2 less than 40 torr. The incompatibility of these results suggest that in future studies HVRs will not be found to be linear, especially below 80% SaO2 and HVRp will fail to be accurately hyperbolic.

  19. Regulation of angiogenin expression and epithelial-mesenchymal transition by HIF-1α signaling in hypoxic retinal pigment epithelial cells.

    Science.gov (United States)

    Lai, Kairan; Luo, Chenqi; Zhang, Xiaobo; Ye, Panpan; Zhang, Yidong; He, Jiliang; Yao, Ke

    2016-09-01

    Choroidal neovascularization (CNV) is a major cause of vision loss in many retinal diseases. Hypoxia is determined to be a key inducer of CNV and hypoxia-inducible factor-1 (HIF-1) is an important transcription factor. Epithelial-mesenchymal transition (EMT) and the synthesis of proangiogenic cytokines make great contributions to the development of CNV. In the present study, the role of HIF-1α signaling in the regulation of angiogenin (ANG) expression and EMT in hypoxic retinal pigment epithelial cells was investigated. A significant elevation expression of ANG expression level in a mouse model of laser-induced CNV was demonstrated. In a hypoxic model of ARPE-19, an increased expression level of ANG and induction of EMT accompanied with stabilization and nucleus translocation of HIF-1α. Blockage of HIF-1α signaling resulted in inhibition of high expression of ANG and EMT features. The direct interaction between HIF-1α and ANG promoter region was identified by ChIP-qPCR. The association of RNase 4 mRNA level with HIF-1α signaling was also clarified in APRE-19. Moreover, the exogenous ANG translocated into the nucleus, enhanced 45S rRNA transcription, promoted cell proliferation and tube formation in human retinal microvascular endothelial cells. In conclusion, the hypoxic conditions regulate the expression of ANG and EMT via an activation of HIF-1α signaling. It provides molecular evidence for potential therapy strategies of treating CNV. PMID:27259982

  20. Ageing, chronic alcohol consumption and folate are determinants of genomic DNA methylation, p16 promoter methylation and the expression of p16 in the mouse colon

    Science.gov (United States)

    Elder age and chronic alcohol consumption are important risk factors for the development of colon cancer. Each factor can alter genomic and gene-specific DNA methylation. This study examined the effects of aging and chronic alcohol consumption on genomic and p16-specific methylation, and p16 express...

  1. Chronic administration of an HDAC inhibitor treats both neurological and systemic Niemann-Pick type C disease in a mouse model.

    Science.gov (United States)

    Alam, Md Suhail; Getz, Michelle; Haldar, Kasturi

    2016-02-17

    Histone deacetylase inhibitors (HDACi) are approved for treating rare cancers and are of interest as potential therapies for neurodegenerative disorders. We evaluated a triple combination formulation (TCF) comprising the pan-HDACi vorinostat, the caging agent 2-hydroxypropyl-β-cyclodextrin (HPBCD), and polyethylene glycol (PEG) for treating a mouse model (the Npc1(nmf164) mouse) of Niemann-Pick type C (NPC) disease, a difficult-to-treat cerebellar disorder. Vorinostat alone showed activity in cultured primary cells derived from Npc1(nmf164) mice but did not improve animal survival. However, low-dose, once-weekly intraperitoneal injections of the TCF containing vorinostat increased histone acetylation in the mouse brain, preserved neurites and Purkinje cells, delayed symptoms of neurodegeneration, and extended mouse life span from 4 to almost 9 months. We demonstrate that the TCF boosted the ability of HDACi to cross the blood-brain barrier and was not toxic even when used long term. Further, the TCF enabled dose reduction, which has been a major challenge in HDACi therapy. TCF simultaneously treats neurodegenerative and systemic symptoms of Niemann-Pick type C disease in a mouse model. PMID:26888431

  2. KLF5 mediates vascular remodeling via HIF-1α in hypoxic pulmonary hypertension.

    Science.gov (United States)

    Li, Xiaochen; He, Yuanzhou; Xu, Yongjian; Huang, Xiaomin; Liu, Jin; Xie, Min; Liu, Xiansheng

    2016-02-15

    Hypoxic pulmonary hypertension (HPH) is characterized by active vasoconstriction and profound vascular remodeling. KLF5, a zinc-finger transcription factor, is involved in the excessive proliferation and apoptotic resistance phenotype associated with monocrotaline-induced pulmonary hypertension. However, the molecular mechanisms of KLF5-mediated pathogenesis of HPH are largely undefined. Adult male Sprague-Dawley rats were exposed to normoxia or hypoxia (10% O2) for 4 wk. Hypoxic rats developed pulmonary arterial remodeling and right ventricular hypertrophy with significantly increased right ventricular systolic pressure. The levels of KLF5 and hypoxia-inducible factor-1α (HIF-1α) were upregulated in distal pulmonary arterial smooth muscle from hypoxic rats. The knockdown of KLF5 via short-hairpin RNA attenuated chronic hypoxia-induced hemodynamic and histological changes in rats. The silencing of either KLF5 or HIF-1α prevented hypoxia-induced (5%) proliferation and migration and promoted apoptosis in human pulmonary artery smooth muscle cells. KLF5 was immunoprecipitated with HIF-1α under hypoxia and acted as an upstream regulator of HIF-1α. The cell cycle regulators cyclin B1 and cyclin D1 and apoptosis-related proteins including bax, bcl-2, survivin, caspase-3, and caspase-9, were involved in the regulation of KLF5/HIF-1α-mediated cell survival. This study demonstrated that KLF5 plays a crucial role in hypoxia-induced vascular remodeling in an HIF-1α-dependent manner and provided a better understanding of the pathogenesis of HPH. PMID:26702149

  3. Advancing hypoxic training in team sports: from intermittent hypoxic training to repeated sprint training in hypoxia.

    Science.gov (United States)

    Faiss, Raphaël; Girard, Olivier; Millet, Grégoire P

    2013-12-01

    Over the past two decades, intermittent hypoxic training (IHT), that is, a method where athletes live at or near sea level but train under hypoxic conditions, has gained unprecedented popularity. By adding the stress of hypoxia during 'aerobic' or 'anaerobic' interval training, it is believed that IHT would potentiate greater performance improvements compared to similar training at sea level. A thorough analysis of studies including IHT, however, leads to strikingly poor benefits for sea-level performance improvement, compared to the same training method performed in normoxia. Despite the positive molecular adaptations observed after various IHT modalities, the characteristics of optimal training stimulus in hypoxia are still unclear and their functional translation in terms of whole-body performance enhancement is minimal. To overcome some of the inherent limitations of IHT (lower training stimulus due to hypoxia), recent studies have successfully investigated a new training method based on the repetition of short (training in hypoxia (RSH). The aims of the present review are therefore threefold: first, to summarise the main mechanisms for interval training and repeated sprint training in normoxia. Second, to critically analyse the results of the studies involving high-intensity exercises performed in hypoxia for sea-level performance enhancement by differentiating IHT and RSH. Third, to discuss the potential mechanisms underpinning the effectiveness of those methods, and their inherent limitations, along with the new research avenues surrounding this topic.

  4. δ-Tocotrienol treatment is more effective against hypoxic tumor cells than normoxic cells: potential implications for cancer therapy.

    Science.gov (United States)

    Shibata, Akira; Nakagawa, Kiyotaka; Tsuduki, Tsuyoshi; Miyazawa, Teruo

    2015-08-01

    Tocotrienols, unsaturated forms of vitamin E, inhibit the proliferation of a variety of cancer cells and suppress angiogenesis. However, the mechanisms underlying those effects on cancer cell growth remain unclear especially under hypoxic conditions. In this study, we demonstrated that δ-tocotrienol (δ-T3) could be used as a novel anticancer agent against human colorectal adenocarcinoma (DLD-1) cells under both normoxic and hypoxic conditions. δ-T3 inhibited the growth of DLD-1 cells in a dose-dependent fashion by inducing cell cycle arrest and apoptosis. This effect was more potent under hypoxic than normoxic conditions. The anticancer effect of δ-T3 was achieved by its up-regulation of cyclin-dependent kinase inhibitors (p21 and p27), the activation of caspases and the suppression of phosphorylation of protein kinase B (Akt) at Thr(308) and Ser(473). In in vivo studies, oral administration of rice bran tocotrienol (RBT3, mainly γ-T3) (10 mg/mouse/day) significantly inhibited tumor growth in nude mice. In tumor analyses, RBT3 activated p21, p27, caspase-3 and caspase-9 and decreased Akt phosphorylation. Furthermore, immunostaining revealed that RBT3 decreased the number of cells positive for CD31/platelet endothelial cell adhesion molecule-1 in microvessels in the tumor. Taken together, these data suggest that tocotrienols are potent antitumor agents capable of inducing apoptosis and inhibiting angiogenesis under both hypoxic and normoxic conditions. Tocotrienols could have significant therapeutic potential in the clinical treatment of tumors. PMID:25979648

  5. 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.

  6. Anti-hyperalgesic effect of a benzilidine-cyclohexanone analogue on a mouse model of chronic constriction injury-induced neuropathic pain: Participation of the κ-opioid receptor and KATP.

    Science.gov (United States)

    Ming-Tatt, Lee; Khalivulla, Shaik Ibrahim; Akhtar, Muhammad Nadeem; Lajis, Nordin; Perimal, Enoch Kumar; Akira, Ahmad; Ali, Daud Israf; Sulaiman, Mohd Roslan

    2013-12-01

    The present study investigated the analgesic effect of a novel synthetic cyclohexanone derivative, 2,6-bis-4-(hydroxyl-3-methoxybenzilidine)-cyclohexanone or BHMC in a mouse model of chronic constriction injury-induced neuropathic pain. It was demonstrated that intraperitoneal administration of BHMC (0.03, 0.1, 0.3 and 1.0mg/kg) exhibited dose-dependent inhibition of chronic constriction injury-induced neuropathic pain in mice, when evaluated using Randall-Selitto mechanical analgesiometer. It was also demonstrated that pretreatment of naloxone (non-selective opioid receptor blocker), nor-binaltorphimine (nor-BNI, selective κ-opioid receptor blocker), but not β-funaltrexamine (β-FN, selective μ-opioid receptor blocker) and naltrindole hydrochloride (NTI, selective δ-opioid receptor blocker), reversed the anti-nociceptive effect of BHMC. In addition, the analgesic effect of BHMC was also reverted by pretreatment of 1H-[1,2,4]Oxadiazole[4,3-a]quinoxalin-1-one (ODQ, soluble guanosyl cyclase blocker) and glibenclamide (ATP-sensitive potassium channel blocker) but not Nω-nitro-l-arginine (l-NAME, a nitric oxide synthase blocker). Taken together, the present study demonstrated that the systemic administration of BHMC attenuated chronic constriction, injury-induced neuropathic pain. We also suggested that the possible mechanisms include κ-opioid receptor activation and nitric oxide-independent cyclic guanosine monophosphate activation of ATP-sensitive potassium channel opening.

  7. The effect of PCO2 on hypoxic pulmonary vasoconstriction.

    Science.gov (United States)

    Noble, W H; Kay, J C; Fisher, J A

    1981-09-01

    Lung areas with a low V/Q ratio cause hypoxaemia. The low alveolar oxygen concentration may cause local hypoxic pulmonary vasoconstriction (HPV) which reduces perfusion, raises the V/Q ratio, and hence reduces the tendency to a low PaO2. By changing PCO2, the HPV response can be altered. We examined this relationship in anaesthetized dogs by using a tracheal divider to separate hypoxic (nitrogen ventilated) from oxygenated (100 per cent oxygen ventilated) lung. Relative perfusion was assessed from total 133Xe exhaled from each lung area after intravenous infusions. When PaCO2 was changed by changing ventilation, we found that an increasing PaCO2 increased HPV and also PaO2. At a PaCO2 of 3.3 kPa, HPV was abolished and PaO2 fell. We also changed PaCO2 by altering PICO2 to one or both lung areas while ventilation remained constant throughout the experiment. Again as PaCO2 increased, HPV and PaCO2 increased. When PaCO2 fell and end tidal carbon dioxide in the hypoxic lung (PETCO2) remained elevated by maintaining PICO2 in the hypoxic lung and removing CO2 from the oxygenated lung) HPV was maintained. Thus it is the alveolar concentration of CO2 in the hypoxic lung which is important in modifying HPV. We conclude that in this model a low PETCO2 (3.3 kPa) in hypoxic lung will reduce HPV, and will result in more severe hypoxaemia. This may have relevance in both anaesthetized and intensive care unit patients when a higher PaO2 may be obtained by increasing hypoxic lung PETCO2. The effect of PETCO2 on PaO2 will be influenced by other variables, but when hypoventilated or hypoxic exist, increasing PETCO2 may reinforce hypoxic pulmonary vasoconstriction and thus may increase PaO2. PMID:6793220

  8. CT and MR in non-neonatal hypoxic-ischemic encephalopathy: radiological findings with pathophysiological correlations

    Energy Technology Data Exchange (ETDEWEB)

    Gutierrez, Leonardo Guilhermino; Portela, Luiz Antonio Pezzi [Hospital Alemao Oswaldo Cruz and Hospital do Coracao, Diagnostic Imaging Division, Sao Paulo (Brazil); Rovira, Alex [University Hospital Vall d' Hebron, MR Unit, Department of Radiology, Barcelona (Spain); Costa Leite, Claudia da [Clinics Hospital of the University of Sao Paulo, School of Medicine, Department of Radiology, Sao Paulo (Brazil); Lucato, Leandro Tavares [Hospital Alemao Oswaldo Cruz and Hospital do Coracao, Diagnostic Imaging Division, Sao Paulo (Brazil); Clinics Hospital of the University of Sao Paulo, School of Medicine, Department of Radiology, Sao Paulo (Brazil)

    2010-11-15

    Non-neonatal hypoxic-ischemic encephalopathy is a clinical condition often related to cardiopulmonary arrest that demands critical management and treatment decisions. Management depends mainly on the degree of neurological impairment and prognostic considerations. Computed tomography (CT) is often used to exclude associated or mimicking pathology. If any, only nonspecific signs such as cerebral edema, sulci effacement, and decreased gray matter (GM)/white matter (WM) differentiation are evident. Pseudosubarachnoid hemorrhage, a GM/WM attenuation ratio <1.18, and inverted GM attenuation are associated with a poor prognosis. Magnetic resonance (MR) imaging is more sensitive than CT in assessing brain damage in hypoxic-ischemic encephalopathy. Some MR findings have similarities to those seen pathologically, based on spatial distribution and time scale, such as lesions distributed in watershed regions and selective injury to GM structures. In the acute phase, lesions are better depicted using diffusion-weighted imaging (DWI) because of the presence of cytotoxic edema, which, on T2-weighted images, only become apparent later in the early subacute phase. In the late subacute phase, postanoxic leukoencephalopathy and contrast enhancement could be observed. In the chronic phase, atrophic changes predominate over tissue signal changes. MR can be useful for estimating prognosis when other tests are inconclusive. Some findings, such as the extent of lesions on DWI and presence of a lactate peak and depleted N-acetyl aspartate peak on MR spectroscopy, seem to have prognostic value. (orig.)

  9. Bead-size directed distribution of Pseudomonas aeruginosa results in distinct inflammatory response in a mouse model of chronic lung infection

    DEFF Research Database (Denmark)

    Christophersen, L J; Trøstrup, H; Damlund, Dina Silke Malling;

    2012-01-01

    Chronic Pseudomonas aeruginosa lung infection in cystic fibrosis (CF) patients is characterized by biofilms, tolerant to antibiotics and host responses. Instead, immune responses contribute to the tissue damage. However, this may depend on localization of infection in the upper conductive...

  10. Exercise-induced oxidative stress and hypoxic exercise recovery.

    Science.gov (United States)

    Ballmann, Christopher; McGinnis, Graham; Peters, Bridget; Slivka, Dustin; Cuddy, John; Hailes, Walter; Dumke, Charles; Ruby, Brent; Quindry, John

    2014-04-01

    Hypoxia due to altitude diminishes performance and alters exercise oxidative stress responses. While oxidative stress and exercise are well studied, the independent impact of hypoxia on exercise recovery remains unknown. Accordingly, we investigated hypoxic recovery effects on post-exercise oxidative stress. Physically active males (n = 12) performed normoxic cycle ergometer exercise consisting of ten high:low intensity intervals, 20 min at moderate intensity, and 6 h recovery at 975 m (normoxic) or simulated 5,000 m (hypoxic chamber) in a randomized counter-balanced cross-over design. Oxygen saturation was monitored via finger pulse oximetry. Blood plasma obtained pre- (Pre), post- (Post), 2 h post- (2Hr), 4 h post- (4Hr), and 6 h (6Hr) post-exercise was assayed for Ferric Reducing Ability of Plasma (FRAP), Trolox Equivalent Antioxidant Capacity (TEAC), Lipid Hydroperoxides (LOOH), and Protein Carbonyls (PC). Biopsies from the vastus lateralis obtained Pre and 6Hr were analyzed by real-time PCR quantify expression of Heme oxygenase 1 (HMOX1), Superoxide Dismutase 2 (SOD2), and Nuclear factor (euthyroid-derived2)-like factor (NFE2L2). PCs were not altered between trials, but a time effect (13 % Post-2Hr increase, p = 0.044) indicated exercise-induced blood oxidative stress. Plasma LOOH revealed only a time effect (p = 0.041), including a 120 % Post-4Hr increase. TEAC values were elevated in normoxic recovery versus hypoxic recovery. FRAP values were higher 6Hr (p = 0.045) in normoxic versus hypoxic recovery. Exercise elevated gene expression of NFE2L2 (20 % increase, p = 0.001) and SOD2 (42 % increase, p = 0.003), but hypoxic recovery abolished this response. Data indicate that recovery in a hypoxic environment, independent of exercise, may alter exercise adaptations to oxidative stress and metabolism. PMID:24384982

  11. Improvement of post-hypoxic action myoclonus with levetiracetam add-on therapy: A case report

    Directory of Open Access Journals (Sweden)

    Božić Ksenija

    2014-01-01

    Full Text Available Introduction. Chronic post-anoxic myoclonus, also known as Lance-Adams syndrome, may develop following hypoxic brain injury, and is resistant to pharmacological therapy. Case report. The patient we presented developed post-anoxic action myoclonus with severe, completely incapacitating myoclonic jerks. Myoclonus did not respond to the treatment with commonly used agents, i.e. valproate and clonazepam alone or in combination. Improvement of the action myoclonus was observed only after adding levetiracetam. Conclusion. Although Lance-Adams syndrome may not be fully curable at this point, levetiracetam appears to be a promising agent that can significantly improve functional level and overall quality of life of patients with this disorder.

  12. Pervasive and opposing effects of Unpredictable Chronic Mild Stress (UCMS) on hippocampal gene expression in BALB/cJ and C57BL/6J mouse strains

    OpenAIRE

    Malki, Karim; Mineur, Yann S.; Tosto, Maria Grazia; Campbell, James; Karia, Priya; Jumabhoy, Irfan; Sluyter, Frans; Crusio, Wim E.; Schalkwyk, Leonard C

    2015-01-01

    Background BALB/cJ is a strain susceptible to stress and extremely susceptible to a defective hedonic impact in response to chronic stressors. The strain offers much promise as an animal model for the study of stress related disorders. We present a comparative hippocampal gene expression study on the effects of unpredictable chronic mild stress on BALB/cJ and C57BL/6J mice. Affymetrix MOE 430 was used to measure hippocampal gene expression from 16 animals of two different strains (BALB/cJ and...

  13. Notch Activation of Ca(2+) Signaling in the Development of Hypoxic Pulmonary Vasoconstriction and Pulmonary Hypertension.

    Science.gov (United States)

    Smith, Kimberly A; Voiriot, Guillaume; Tang, Haiyang; Fraidenburg, Dustin R; Song, Shanshan; Yamamura, Hisao; Yamamura, Aya; Guo, Qiang; Wan, Jun; Pohl, Nicole M; Tauseef, Mohammad; Bodmer, Rolf; Ocorr, Karen; Thistlethwaite, Patricia A; Haddad, Gabriel G; Powell, Frank L; Makino, Ayako; Mehta, Dolly; Yuan, Jason X-J

    2015-09-01

    Hypoxic pulmonary vasoconstriction (HPV) is an important physiological response that optimizes the ventilation/perfusion ratio. Chronic hypoxia causes vascular remodeling, which is central to the pathogenesis of hypoxia-induced pulmonary hypertension (HPH). We have previously shown that Notch3 is up-regulated in HPH and that activation of Notch signaling enhances store-operated Ca(2+) entry (SOCE), an important mechanism that contributes to pulmonary arterial smooth muscle cell (PASMC) proliferation and contraction. Here, we investigate the role of Notch signaling in HPV and hypoxia-induced enhancement of SOCE. We examined SOCE in human PASMCs exposed to hypoxia and pulmonary arterial pressure in mice using the isolated perfused/ventilated lung method. Wild-type and canonical transient receptor potential (TRPC) 6(-/-) mice were exposed to chronic hypoxia to induce HPH. Inhibition of Notch signaling with a γ-secretase inhibitor attenuates hypoxia-enhanced SOCE in PASMCs and hypoxia-induced increase in pulmonary arterial pressure. Our results demonstrate that hypoxia activates Notch signaling and up-regulates TRPC6 channels. Additionally, treatment with a Notch ligand can mimic hypoxic responses. Finally, inhibition of TRPC6, either pharmacologically or genetically, attenuates HPV, hypoxia-enhanced SOCE, and the development of HPH. These results demonstrate that hypoxia-induced activation of Notch signaling mediates HPV and the development of HPH via functional activation and up-regulation of TRPC6 channels. Understanding the molecular mechanisms that regulate cytosolic free Ca(2+) concentration and PASMC proliferation is critical to elucidation of the pathogenesis of HPH. Targeting Notch regulation of TRPC6 will be beneficial in the development of novel therapies for pulmonary hypertension associated with hypoxia. PMID:25569851

  14. Satellite-based empirical models linking river plume dynamics with hypoxic area andvolume

    Science.gov (United States)

    Satellite-based empirical models explaining hypoxic area and volume variation were developed for the seasonally hypoxic (O2 < 2 mg L−1) northern Gulf of Mexico adjacent to the Mississippi River. Annual variations in midsummer hypoxic area and ...

  15. Homogentisate 1-2-Dioxygenase Downregulation in the Chronic Persistence of Pseudomonas aeruginosa Australian Epidemic Strain-1 in the CF Lung.

    Science.gov (United States)

    Harmer, Christopher J; Wynn, Matthew; Pinto, Rachel; Cordwell, Stuart; Rose, Barbara R; Harbour, Colin; Triccas, James A; Manos, Jim

    2015-01-01

    Some Pseudomonas aeruginosa strains including Australian Epidemic Strain-1 (AES-1 or AUS-01) cause persistent chronic infection in cystic fibrosis (CF) patients, with greater morbidity and mortality. Factors conferring persistence are largely unknown. Previously we analysed the transcriptomes of AES-1 grown in Luria broth, nematode growth medium for Caenorhabditis elegans assay (both aerobic) and artificial sputum medium (mainly hypoxic). Transcriptional comparisons included chronic AES-1 strains against PAO1 and acute AES-1 (AES-1R) against its chronic isogen (AES-1M), isolated 10.5 years apart from a CF patient and not eradicated in the meantime. Prominent amongst genes downregulated in AES-1M in all comparisons was homogentisate-1-2-dioxygenase (hmgA); an oxygen-dependent gene known to be mutationally deactivated in many chronic infection strains of P. aeruginosa. To investigate if hmgA downregulation and deactivation gave similar virulence persistence profiles, a hmgA mutant made in UCBPP-PA14 utilising RedS-recombinase and AES-1M were assessed in the C. elegans virulence assay, and the C57BL/6 mouse for pulmonary colonisation and TNF-α response. In C. elegans, hmgA deactivation resulted in significantly increased PA14 virulence while hmgA downregulation reduced AES-1M virulence. AES-1M was significantly more persistent in mouse lung and showed a significant increase in TNF-α (p<0.0001), sustained even with no detectable bacteria. PA14ΔhmgA did not show increased TNF-α. This study suggests that hmgA may have a role in P. aeruginosa persistence in chronic infection and the results provide a starting point for clarifying the role of hmgA in chronic AES-1. PMID:26252386

  16. Perinatal Hypoxic-Ischemic brain injury; MR findings

    Energy Technology Data Exchange (ETDEWEB)

    Park, Dong Woo; Seo, Chang Hye [Inje University Pusan Paik Hospital, Pusan (Korea, Republic of)

    1994-09-15

    To characterize the MR findings of hypoxic-ischemic brain injury and to assess the value of the MR imaging. SE T1-, T2-weighted, and IR brain MR images of 44 infants and children with the past history of perinatal hypoxic insults were reviewed. Abnormal brain MR findings of 8 patients with birth history of prematurity and 36 patients with birth history of full-term/posterm including 7 with severe anoxic insult history, were compared in regard to the location and the character of the lesions. MRI demonstrated the followings; (1)abnormal signal intensity lesions of subcortical and/or deep cerebral white matter, cortex, and deep gray matter, (2)atrophy of the cerebral white matter, cortex and corpus callosum, with/without ventriculomegaly, and (3)delay in myelination. Periventricular and deep white matter lesions were demonstrated in the prematurity, the deep white matter lesions and/ or subcortical white matter lesions in the term/post-term, and deep gray matter lesions in the 7 patients with severe anoxic insults history. MR imaging was useful in the diagnosis of the hypoxic-ischemic brain injury, and the white and gray matter lesions were correlated with the time of the injury and the severity of hypoxic insult.

  17. Patterns of neonatal hypoxic-ischaemic brain injury

    Energy Technology Data Exchange (ETDEWEB)

    Vries, Linda S. de [University Medical Centre, Department of Neonatology, Wilhelmina Children' s Hospital, Utrecht (Netherlands); Wilhelmina Children' s Hospital, University Medical Centre, Department of Neonatology, KE 04.123.1, P.O. Box 85090, Utrecht (Netherlands); Groenendaal, Floris [University Medical Centre, Department of Neonatology, Wilhelmina Children' s Hospital, Utrecht (Netherlands)

    2010-06-15

    Enormous progress has been made in assessing the neonatal brain, using magnetic resonance imaging (MRI). In this review, we will describe the use of MRI and proton magnetic resonance spectroscopy in detecting different patterns of brain injury in (full-term) human neonates following hypoxic-ischaemic brain injury and indicate the relevance of these findings in predicting neurodevelopmental outcome. (orig.)

  18. Hypoxic-Ischemic-Encephalopathy Studied by EEG and Mr Spectroscopy

    OpenAIRE

    J Gordon Millichap

    2011-01-01

    Amplitude-integrated EEG (a-EEG) time course during the first 24 hrs of life was related to brain metabolism changes detected by proton MR spectroscopy (H-MRS) at 7-10 days of post-natal life in non-cooled term newborns with hypoxic-ischemic-encephalopathy (HIE).

  19. Nitrous oxide emissions from the Gulf of Mexico Hypoxic Zone

    Science.gov (United States)

    The production of nitrous oxide (N2O), a potent greenhouse gas, in hypoxic coastal zones remains poorly characterized due to a lack of data, though large nitrogen inputs and deoxygenation typical of these systems create the potential for large N2O emissions. We report the first N...

  20. Chronic consumption of a western diet induces robust glial activation in aging mice and in a mouse model of Alzheimer’s disease

    OpenAIRE

    Graham, Leah C.; Harder, Jeffrey M.; Ileana Soto; de Vries, Wilhelmine N.; Simon W M John; Gareth R Howell

    2016-01-01

    Studies have assessed individual components of a western diet, but no study has assessed the long-term, cumulative effects of a western diet on aging and Alzheimer’s disease (AD). Therefore, we have formulated the first western-style diet that mimics the fat, carbohydrate, protein, vitamin and mineral levels of western diets. This diet was fed to aging C57BL/6J (B6) mice to identify phenotypes that may increase susceptibility to AD, and to APP/PS1 mice, a mouse model of AD, to determine the e...

  1. Chemotherapeutic attack of hypoxic tumor cells by the bioreductive alkylating agent mitomycin C.

    Science.gov (United States)

    Keyes, S R; Heimbrook, D C; Fracasso, P M; Rockwell, S; Sligar, S G; Sartorelli, A C

    1985-01-01

    Since the cure of solid tumors is limited by the presence of cells with low oxygen contents, we have approached the development of treatment regimens and of new drugs for these tumors by investigating agents which are preferentially bioactivated under hypoxia. Major emphasis has been directed at studying the mode of action of the mitomycin antibiotics, as bioreductive alkylating agents. Using primarily the EMT6 mouse mammary carcinoma as a solid tumor model, we have found that mitomycin C and porfiromycin are preferentially toxic to cells with low oxygen contents. The mitomycin analog BMY-25282 is more toxic to hypoxic cells than are mitomycin C and porfiromycin; however, unlike these antibiotics, BMY-25282 is preferentially toxic to well-oxygenated cells. With these three mitomycins, we have observed a correlation between cytotoxicity to hypoxic cells, the rate of generation of reactive products, and the redox potentials of the drugs. Investigations of the enzymes in EMT6 cells that could possibly activate mitomycin C have revealed that cytochrome P-450 and xanthine oxidase are not present in measurable quantities and therefore are not responsible for activation of mitomycin C. Activities representative of NADPH-cytochrome c reductase and DT-diaphorase are present in these neoplastic cells. Comparison of these enzymatic activities in EMT6, CHO, and V79 cells with the rate of generation of reactive products under hypoxia shows a direct correlation between these two parameters, but there is no quantitative correlation between these two parameters and the amount of cytotoxicity. Use of purified NADPH-cytochrome c reductase and inhibitors of this enzyme demonstrated that NADPH-cytochrome c reductase can activate mitomycin C, but that it is probably not the only enzyme participating in this bioactivation in EMT6 cells. The DT-diaphorase inhibitor dicoumarol was employed to show that this enzyme is not involved in the activation of mitomycin C to a cytotoxic agent

  2. Real-Time Bioluminescence Imaging of Nitroreductase in Mouse Model.

    Science.gov (United States)

    Feng, Ping; Zhang, Huateng; Deng, Quankun; Liu, Wei; Yang, Linghui; Li, Guobo; Chen, Guo; Du, Lupei; Ke, Bowen; Li, Minyong

    2016-06-01

    Nitroreductase (NTR) is an endogenous reductase overexpressed in hypoxic tumors; however, its precise detection in living cells and animals remains a considerable challenge. Herein, we developed three reaction-based probes and a related bioluminescence assay for the real-time NTR detection. The high sensitivity and selectivity of probe 3, combined with its remarkable potential of bioluminescence imaging, affords a valuable approach for in vivo imaging of NTR in a tumor model mouse. PMID:27197544

  3. Real-Time Bioluminescence Imaging of Nitroreductase in Mouse Model.

    Science.gov (United States)

    Feng, Ping; Zhang, Huateng; Deng, Quankun; Liu, Wei; Yang, Linghui; Li, Guobo; Chen, Guo; Du, Lupei; Ke, Bowen; Li, Minyong

    2016-06-01

    Nitroreductase (NTR) is an endogenous reductase overexpressed in hypoxic tumors; however, its precise detection in living cells and animals remains a considerable challenge. Herein, we developed three reaction-based probes and a related bioluminescence assay for the real-time NTR detection. The high sensitivity and selectivity of probe 3, combined with its remarkable potential of bioluminescence imaging, affords a valuable approach for in vivo imaging of NTR in a tumor model mouse.

  4. Impact of exercise on mitochondrial transcription factor expression and damage in the striatum of a chronic mouse model of Parkinson’s disease

    OpenAIRE

    Patki, Gaurav; Lau, Yuen-Sum

    2011-01-01

    The etiology of neurodegenerative disorders like Parkinson’s disease remains unknown, although many genetic and environmental factors are suggested as likely causes. Neuronal oxidative stress and mitochondrial dysfunction have been implicated as possible triggers for the onset and progression of Parkinson’s neurodegeneration. We have recently shown that long-term treadmill exercise prevented neurological, mitochondrial and locomotor deficits in a chronic 1-methyl-4-phenyl-1,2,3,6-tetrahydropy...

  5. TNFα mediates stress-induced depression by upregulating indoleamine 2,3-dioxygenase in a mouse model of unpredictable chronic mild stress

    OpenAIRE

    Liu, Yu-Ning; Peng, Yun-Li; Lei-Liu,; Wu, Teng-Yun; Zhang, Yi; Lian, Yong-Jie; Yang, Yuan-Yuan; Kelley, Keith W.; Jiang, Chun-Lei; Wang, Yun-Xia

    2015-01-01

    Depression is often preceded by exposure to stressful life events. Chronic stress causes perturbations in the immune system, and up-regulates production of proinflammatory cytokines, which has been proposed to be associated with the pathogenesis of clinical depression. However, the potential mechanisms by which stress-induced proinflammatory cytokines lead to the development of depression are not well understood. Here, we sought to screen the main proinflammatory cytokines and the potential m...

  6. Larger adaptive response of 5-HT1A autoreceptors to chronic fluoxetine in a mouse model of depression than in healthy mice

    Institute of Scientific and Technical Information of China (English)

    N.FROGER; E.PALAZZO; T.RENOIR; M.MELFORT; N.BARDEN; M.HAMON; L.LANFUMEY

    2004-01-01

    Vulnerability to major depressive disorders, in particular depression, is often associated with both hypoactivity of the central serotoninergic (5-HT) system and hyperactivity of the hypothalamic-pituitary-adrenal (HPA) axis. Extensive studies in normal healthy rodents showed that chronic treatment with SSRI antidepressants produced a marked functional desensitization of somatodendritic 5-HT1A autoreceptors, and this adaptive change has been claimed to play a key role in the therapeutic action of

  7. Chronic Pancreatitis and Systemic Inflammatory Response Syndrome Prevent Impact of Chemotherapy with Gemcitabine in a Genetically Engineered Mouse Model of Pancreatic Cancer

    Directory of Open Access Journals (Sweden)

    Richard F. Knoop

    2014-06-01

    CONCLUSION: We could demonstrate for the first time that an improvement in median overall survival with gemcitabine is significantly abolished by a persistent mild chronic pancreatitis and a systemic inflammatory response syndrome. In particular, the inflammation biomarkers C-reactive protein, IL-6, and IL-1α could indicate the prognostic benefit of gemcitabine chemotherapy and should now be tested in prospective patient-controlled trials.

  8. Human neural stem cells differentiate and promote locomotor recovery in an early chronic spinal cord injury NOD-scid mouse model.

    Directory of Open Access Journals (Sweden)

    Desirée L Salazar

    Full Text Available BACKGROUND: Traumatic spinal cord injury (SCI results in partial or complete paralysis and is characterized by a loss of neurons and oligodendrocytes, axonal injury, and demyelination/dysmyelination of spared axons. Approximately 1,250,000 individuals have chronic SCI in the U.S.; therefore treatment in the chronic stages is highly clinically relevant. Human neural stem cells (hCNS-SCns were prospectively isolated based on fluorescence-activated cell sorting for a CD133(+ and CD24(-/lo population from fetal brain, grown as neurospheres, and lineage restricted to generate neurons, oligodendrocytes and astrocytes. hCNS-SCns have recently been transplanted sub-acutely following spinal cord injury and found to promote improved locomotor recovery. We tested the ability of hCNS-SCns transplanted 30 days post SCI to survive, differentiate, migrate, and promote improved locomotor recovery. METHODS AND FINDINGS: hCNS-SCns were transplanted into immunodeficient NOD-scid mice 30 days post spinal cord contusion injury. hCNS-SCns transplanted mice demonstrated significantly improved locomotor recovery compared to vehicle controls using open field locomotor testing and CatWalk gait analysis. Transplanted hCNS-SCns exhibited long-term engraftment, migration, limited proliferation, and differentiation predominantly to oligodendrocytes and neurons. Astrocytic differentiation was rare and mice did not exhibit mechanical allodynia. Furthermore, differentiated hCNS-SCns integrated with the host as demonstrated by co-localization of human cytoplasm with discrete staining for the paranodal marker contactin-associated protein. CONCLUSIONS: The results suggest that hCNS-SCns are capable of surviving, differentiating, and promoting improved locomotor recovery when transplanted into an early chronic injury microenvironment. These data suggest that hCNS-SCns transplantation has efficacy in an early chronic SCI setting and thus expands the "window of opportunity" for

  9. Neuroendocrine and cardiac metabolic dysfunction and NLRP3 inflammasome activation in adipose tissue and pancreas following chronic spinal cord injury in the mouse

    Directory of Open Access Journals (Sweden)

    Mark S. Nash

    2013-09-01

    Full Text Available CVD (cardiovascular disease represents a leading cause of mortality in chronic SCI (spinal cord injury. Several component risk factors are observed in SCI; however, the underlying mechanisms that contribute to these risks have not been defined. Central and peripheral chronic inflammation is associated with metabolic dysfunction and CVD, including adipokine regulation of neuroendocrine and cardiac function and inflammatory processes initiated by the innate immune response. We use female C57 Bl/6 mice to examine neuroendocrine, cardiac, adipose and pancreatic signaling related to inflammation and metabolic dysfunction in response to experimentally induced chronic SCI. Using immuno-histochemical, -precipitation, and -blotting analysis, we show decreased POMC (proopiomelanocortin and increased NPY (neuropeptide-Y expression in the hypothalamic ARC (arcuate nucleus and PVN (paraventricular nucleus, 1-month post-SCI. Long-form leptin receptor (Ob-Rb, JAK2 (Janus kinase/STAT3 (signal transducer and activator of transcription 3/p38 and RhoA/ROCK (Rho-associated kinase signaling is significantly increased in the heart tissue post-SCI, and we observe the formation and activation of the NLRP3 (NOD-like receptor family, pyrin domain containing 3 inflammasome in VAT (visceral adipose tissue and pancreas post-SCI. These data demonstrate neuroendocrine signaling peptide alterations, associated with central inflammation and metabolic dysfunction post-SCI, and provide evidence for the peripheral activation of signaling mechanisms involved in cardiac, VAT and pancreatic inflammation and metabolic dysfunction post-SCI. Further understanding of biological mechanisms contributing to SCI-related inflammatory processes and metabolic dysfunction associated with CVD pathology may help to direct therapeutic and rehabilitation countermeasures.

  10. Effects of eslicarbazepine acetate on acute and chronic latrunculin A-induced seizures and extracellular amino acid levels in the mouse hippocampus

    OpenAIRE

    Sierra-Paredes, Germán; Loureiro, Ana I; Wright, Lyndon C; Sierra-Marcuño, Germán; Soares-da-Silva, Patrício

    2014-01-01

    Background Latrunculin A microperfusion of the hippocampus induces acute epileptic seizures and long-term biochemical changes leading to spontaneous seizures. This study tested the effect of eslicarbazepine acetate (ESL), a novel antiepileptic drug, on latrunculin A-induced acute and chronic seizures, and changes in brain amino acid extracellular levels. Hippocampi of Swiss mice were continuously perfused with a latrunculin A solution (4 μM, 1 μl/min, 7 h/day) with continuous EEG and videotap...

  11. Experimental studies of VEGF-C gene for the treatment of chronic obstructive lymphedema in mouse tail model%VEGF-C局部注射治疗阻塞性淋巴水肿的实验研究

    Institute of Scientific and Technical Information of China (English)

    胡学庆; 蒋朝华; 刘宁飞

    2008-01-01

    Objective To study the therapeutic effect of vascular endothelial growth factor C(VEGF-C)gene for chronic obstructive lymphedema in mouse tail model which may provide a new treatment for lymphedema.Methods RT-PCR and immunoabsorption were applied to detect VEGF-C gene expression in fibroblasts and secretion of VEGF-C protein in COS7 cells respectively after pCDNA3.1(+)VEGF-C transfection.A mouse tail model of chronic obstructive lymphedema was created.Then the pcDNA3.1-VEGF-C plasmid was injected into the tail.The effect of modulating lymphangiogenesis was observed. Results Compared with control group,overexpression of VEGF-C enhanced lymphangiogenesis in vivo and mouse tail skin suffering chronic obstructive lymphedema was improved by VEGF-C gene significantly.Conclusions VEGF-C can improve the lymphedema through enhancing lymphangiogenesis.%目的 研究血管内皮生长因子C(VEGF-C)局部注射对治疗小鼠尾部阻塞性淋巴水肿的作用,探讨治疗淋巴水肿的新方法.方法 应用RT-PCR、免疫荧光和Western Blot方法检测重组pcDNA3.1-VEGF-C质粒在成纤维细胞和COS细胞中表达和蛋白分泌情况;通过手术方法建立小鼠尾部慢性阻塞性淋巴水肿模型;pCDNA3.1-VEGF-C质粒尾部注射,测量鼠尾直径、鼠尾淋巴管显影、组织学检测及LYVE-1免疫组织化学淋巴管计数,结果进行t检验的统计学分析.结果 重组pcDNA3.1-VEGF-C质粒所携带的目的基因人VEGF-C能够在细胞中表达,而且还能够分泌到细胞外;成功建立了小鼠尾部慢性阻塞性淋巴水肿模型;VEGF-C局部注射后,鼠尾直径变小、淋巴管的数目增多,与对照组比较差异有统计学意义(P<0.05).结论 VEGF-C转基因通过促进淋巴管的再生可以缓解淋巴水肿.

  12. Chronic pancreatitis

    Science.gov (United States)

    Chronic pancreatitis - chronic; Pancreatitis - chronic - discharge; Pancreatic insufficiency - chronic; Acute pancreatitis - chronic ... abuse over many years. Repeated episodes of acute pancreatitis can lead to chronic pancreatitis. Genetics may be ...

  13. [Establishment of hepatitis B virus (HBV) chronic infection mouse model by in vivo transduction with a recombinant adeno-associated virus 8 carrying 1. 3 copies of HBV genome (rAAN8-1. 3HBV)].

    Science.gov (United States)

    Dong, Xiao-Yan; Yu, Chi-Jie; Wang, Gang; Tian, Wen-Hong; Lu, Yue; Zhang, Feng-Wei; Wang, Wen; Wang, Yue; Tan, Wen-Jie; Wu, Xiao-Bing

    2010-11-01

    In this report, we developed a HBV infection model in C57BL/6 mouse line by in vivo injection of a recombinant adeno-associated virus 8 vector carrying 1. 3 copies of HBV genome (ayw subtype) (rAAV8-1. 3HBV). We firstly prepared and purified the rAAV8-1. 3HBV and then injected it into three C57BL/6 mice with the dose of 2 x 10e11vg, respectively. HBsAg and HBeAg were assayed in sera collected at different time points post injection. Ten weeks post injection, the three mice were sacrificed and blood and liver tissue were taken for assay. Copies of HBV DNA were detected by real time PCR and the way of HBV DNA replication was identified by PCR. Subsequently, detection of HBV antigen by immunohistochemistry and pathology analysis of liver tissue of mice were performed. The results suggested that expression of HBsAg and HBeAg lasted for at least 10 weeks in mice sera. Among mice injected with rAAV8-1. 3HBV, HBsAg levels were showed an 'increasing-decreasing-increasing' pattern (the lowest level at the 4th week post injection), while HBeAg levels were kept high and relatively stable. HBV DNA copies were 4.2 x 10(3), 3.6 x 10(3), 2.5 x 10(3) copies/mL in sera and 8.0 x 10(6), 5.7 x 10(6), 2.6 x 10(6) copies/g in hepatic tissues of three mice, respectively. We found that the linear 1. 3HBV DNA in the rAAV8-1. 3HBV could self form into circular HBV genome and replicate in livers of HBV transfected mice. HBsAg and HBcAg were both positive in liver tissue of mice injected with rAAV8-1. 3HBV and no obvious pathological characters were found in liver of mice injected with rAAV8-1. 3HBV. In conclusion, we successfully developed a HBV chronic infection model in C57BL/6 mouse line by in vivo transduction with the recombinant virus rAAV8-1. 3HBV, in which HBV genes could be continuously expressed and replicated over 10 weeks, and paved a way for further characterization of the human chronic hepatitis B virus infection and evaluation of vaccine and anti-HBV agents. PMID:21344744

  14. Κ-opioid receptor stimulation improves endothelial function in hypoxic pulmonary hypertension.

    Directory of Open Access Journals (Sweden)

    Qi Wu

    Full Text Available The present study was designed to investigate the effect of κ-opioid receptor stimulation with U50,488H on endothelial function and underlying mechanism in rats with hypoxic pulmonary hypertension (HPH. Chronic hypoxia-induced HPH was simulated by exposing the rats to 10% oxygen for 2 wk. After hypoxia, mean pulmonary arterial pressure (mPAP, right ventricular pressure (RVP and right ventricular hypertrophy index (RVHI were measured. Relaxation of pulmonary artery in response to acetylcholine (ACh was determined. Expression and activity of endothelial nitric oxide (NO synthase (eNOS and inducible NO synthase (iNOS with NO production, total antioxidant capacity (T-AOC, gp91(phox expression and nitrotyrosine content were measured. The effect of U50,488H administration during chronic hypoxia was investigated. Administration of U50,488H significantly decreased mPAP and right ventricular hypertrophy as evidenced by reduction in RVP and RVHI. These effects were mediated by κ-opioid receptor. In the meantime, treatment with U50,488H significantly improved endothelial function as evidenced by enhanced relaxation in response to ACh. Moreover, U50,488H resulted in a significant increase in eNOS phosphorylation, NO content in serum, and T-AOC in pulmonary artery of HPH rats. In addition, the activity of eNOS was enhanced, but the activity of iNOS was attenuated in the pulmonary artery of chronic hypoxic rats treated with U50,488H. On the other hand, U50,488H markedly blunted HPH-induced elevation of gp91(phox expression and nitrotyrosine content in pulmonary artery, and these effects were blocked by nor-BNI, a selective κ-opioid receptor antagonist. These data suggest that κ-opioid receptor stimulation with U50,488H improves endothelial function in rats with HPH. The mechanism of action might be attributed to the preservation of eNOS activity, enhancement of eNOS phosphorylation, downregulation of iNOS activity and its antioxidative/nitrative effect.

  15. Lung mast cells and hypoxic pulmonary vasoconstriction in cats

    Energy Technology Data Exchange (ETDEWEB)

    Martin, L.F.; Tucker, A.; Munroe, M.L.; Reeves, J.T.

    1978-01-01

    An attempt was made to reduce or eliminate lung mast cells in order to determine the involvement of mast cells in hypoxic pulmonary vasoconstriction. Anesthetized cats were exposed to acute hypoxia (10% O/sub 2/) 20 to 24 h after no pretreatment, after total lung irradiation (3,000 r), after intravenous nitrogen mustard, or after combined lung irradiation and nitrogen mustard. None of the treatments reduced total or perivascular lung mast cell density, or reduced the pulmonary vasoconstrictor response to hypoxia. However, an inverse relationship between lung mast cell density and the pulmonary pressor response to hypoxia was observed. These results suggest that the presence of more lung mast cells may oppose hypoxic pulmonary vasoconstriction.

  16. Popularity of hypoxic training methods for endurance-based professional and amateur athletes.

    Science.gov (United States)

    Álvarez-Herms, J; Julià-Sánchez, S; Hamlin, M J; Corbi, F; Pagès, T; Viscor, G

    2015-05-01

    Scientific debate continues into whether hypoxic training has any performance benefit for athletes, and although this type of training seems popular, to our knowledge little empirical evidence on its popularity with endurance-based athletes exists. To quantify the usage of hypoxic training in endurance-based athletes we asked 203 athletes (amateur = 108, professional = 95) to complete a 17-question survey during 2013-2014 season. Compared to amateurs, professional athletes were 4.5 times (3.0-6.8, odds ratio, 95% confidence limits) more likely to undertake hypoxic training. Live-high train-low was the most popular hypoxic training protocol for athletes (52% professional and 80% amateur) with live-high train-high also used (38% professional, 20% amateur). Compared to amateurs, professional athletes tended to use evidence-based hypoxic training methods, seek advice on hypoxic training from reliable sources and were generally more realistic about the potential performance gains as a result of hypoxic training. Almost one third (25-30%) of all athletes suffered illness during their hypoxic training. Compared to amateurs, professional athletes are more likely to undertake hypoxic training and tend to follow current scientific guidelines. Attenuation of the ill effects that occur during hypoxic training may be accomplished if athletes give more attention to monitoring stress and training levels.

  17. Frequency of hypoxic events in patients on a mechanical ventilator

    OpenAIRE

    Mahmood, Nader A; Chaudry, Fawad A.; Azam, Hamad; Ali, M. Imran; Khan, M. Anees

    2013-01-01

    Background: Mechanical ventilation is an important tool in the management of respiratory failure in the critically ill patient. Although mechanical ventilation can be a life-saving intervention, it is also known to carry several side-effects and risks. Adequate oxygenation is one of the primary goals of mechanical ventilation. However, while on mechanical ventilation, patients frequently experience hypoxic events resulting from various causes, which need to be properly evaluated and treated. ...

  18. Excess post hypoxic oxygen consumption in Atlantic cod (Gadus morhua)

    DEFF Research Database (Denmark)

    Plambech, M.; Deurs, Mikael van; Steffensen, J.F.;

    2013-01-01

    Atlantic cod Gadus morhua experienced oxygen deficit (DO2 ) when exposed to oxygen levels below their critical level (c. 73% of pcrit) and subsequent excess post-hypoxic oxygen consumption (CEPHO) upon return to normoxic conditions, indicative of an oxygen debt. The mean±s.e. CEPHO:DO2 was 6·9±1·......·9±1·5, suggesting that resorting to anaerobic energy production in severe hypoxia is energetically expensive...

  19. Stem Cell Therapy for Neonatal Hypoxic-Ischemic Encephalopathy

    OpenAIRE

    Gabriel eGonzales-Portillo; Stephanny eReyes; Daniela eAguirre; Pabon, Mibel M.; Borlongan, Cesar V.

    2014-01-01

    Treatments for neonatal hypoxic-ischemic encephalopathy (HIE) have been limited. The aim of this paper is to offer translational research guidance on stem cell therapy for neonatal HIE by examining clinically relevant animal models, practical stem cell sources, safety and efficacy of endpoint assays, as well as a general understanding of modes of action of this cellular therapy. In order to do so, we discuss the clinical manifestations of HIE, highlighting its overlapping pathologies with str...

  20. Accumulation of Regulatory T Cells and Chronic Inflammation in the Middle Ear in a Mouse Model of Chronic Otitis Media with Effusion Induced by Combined Eustachian Tube Blockage and Nontypeable Haemophilus influenzae Infection.

    Science.gov (United States)

    Hirano, Takashi; Kodama, Satoru; Kawano, Toshiaki; Suzuki, Masashi

    2016-01-01

    Nontypeable Haemophilus influenzae (NTHi) is associated with chronic otitis media (COM). In this study, we generated a murine model of COM by using eustachian tube (ET) obstruction and NTHi (10(7) CFU) inoculation into the tympanic bulla, and we investigated the relationship between regulatory T cells (Treg) and chronic inflammation in the middle ear. Middle ear effusions (MEEs) and middle ear mucosae (MEM) were collected at days 3 and 14 and at 1 and 2 months after inoculation. Untreated mice served as controls. MEEs were used for bacterial counts and to measure the concentrations of cytokines. MEM were collected for histological evaluation and flow cytometric analysis. Inflammation of the MEM was prolonged throughout this study, and the incidence of NTHi culture-positive MEE was 38% at 2 months after inoculation. The levels of interleukin-1β (IL-β), tumor necrosis factor alpha, IL-10, and transforming growth factor β were increased in the middle ear for up to 2 months after inoculation. CD4(+) CD25(+) FoxP3(+) Treg accumulated in the middle ear, and the percentage of Treg in the MEM increased for up to 2 months after inoculation. Treg depletion induced a 99.9% reduction of bacterial counts in MEEs and also significantly reduced the ratio of NTHi culture-positive MEE. The levels of these cytokines were also reduced in MEEs. In summary, we developed a murine model of COM, and our findings indicate that Treg confer infectious tolerance to NTHi in the middle ear.

  1. Chronic exposure to arsenic in drinking water can lead to resistance to antimonial drugs in a mouse model of visceral leishmaniasis

    Science.gov (United States)

    Perry, Meghan R.; Wyllie, Susan; Raab, Andrea; Feldmann, Joerg; Fairlamb, Alan H.

    2013-01-01

    The Indian subcontinent is the only region where arsenic contamination of drinking water coexists with widespread resistance to antimonial drugs that are used to treat the parasitic disease visceral leishmaniasis. We have previously proposed that selection for parasite resistance within visceral leishmaniasis patients who have been exposed to trivalent arsenic results in cross-resistance to the related metalloid antimony, present in the pentavalent state as a complex in drugs such as sodium stibogluconate (Pentostam) and meglumine antimonate (Glucantime). To test this hypothesis, Leishmania donovani was serially passaged in mice exposed to arsenic in drinking water at environmentally relevant levels (10 or 100 ppm). Arsenic accumulation in organs and other tissues was proportional to the level of exposure and similar to that previously reported in human liver biopsies. After five monthly passages in mice exposed to arsenic, isolated parasites were found to be completely refractory to 500 μg⋅mL−1 Pentostam compared with the control passage group (38.5 μg⋅mL−1) cultured in vitro in mouse peritoneal macrophages. Reassessment of resistant parasites following further passage for 4 mo in mice without arsenic exposure showed that resistance was stable. Treatment of infected mice with Pentostam confirmed that resistance observed in vitro also occurred in vivo. We conclude that arsenic contamination may have played a significant role in the development of Leishmania antimonial resistance in Bihar because inadequate treatment with antimonial drugs is not exclusive to India, whereas widespread antimonial resistance is. PMID:24167266

  2. Chronic exposure to arsenic in drinking water can lead to resistance to antimonial drugs in a mouse model of visceral leishmaniasis.

    Science.gov (United States)

    Perry, Meghan R; Wyllie, Susan; Raab, Andrea; Feldmann, Joerg; Fairlamb, Alan H

    2013-12-01

    The Indian subcontinent is the only region where arsenic contamination of drinking water coexists with widespread resistance to antimonial drugs that are used to treat the parasitic disease visceral leishmaniasis. We have previously proposed that selection for parasite resistance within visceral leishmaniasis patients who have been exposed to trivalent arsenic results in cross-resistance to the related metalloid antimony, present in the pentavalent state as a complex in drugs such as sodium stibogluconate (Pentostam) and meglumine antimonate (Glucantime). To test this hypothesis, Leishmania donovani was serially passaged in mice exposed to arsenic in drinking water at environmentally relevant levels (10 or 100 ppm). Arsenic accumulation in organs and other tissues was proportional to the level of exposure and similar to that previously reported in human liver biopsies. After five monthly passages in mice exposed to arsenic, isolated parasites were found to be completely refractory to 500 μg · mL(-1) Pentostam compared with the control passage group (38.5 μg · mL(-1)) cultured in vitro in mouse peritoneal macrophages. Reassessment of resistant parasites following further passage for 4 mo in mice without arsenic exposure showed that resistance was stable. Treatment of infected mice with Pentostam confirmed that resistance observed in vitro also occurred in vivo. We conclude that arsenic contamination may have played a significant role in the development of Leishmania antimonial resistance in Bihar because inadequate treatment with antimonial drugs is not exclusive to India, whereas widespread antimonial resistance is.

  3. Anti hypoxic and antioxidant activity of Hibiscus esculentus seeds

    Energy Technology Data Exchange (ETDEWEB)

    Ebrahimzadeh, M. A.; Nabavi, S. F.; Nabavi, S. M.; Eslami, B.

    2010-07-01

    The anti hypoxic and antioxidant activities of Hibiscus esculentus seeds were investigated employing eight in vitro assay systems. Anti hypoxic activity was investigated in two models, haemic and circulatory. The effects were pronounced in both models of hypoxia. The anti hypoxic effects were dose-dependent. The results indicated that the extracts have a protective effect against hypoxia induced lethality in mice. The extracts showed antioxidant activity in some models. IC{sub 5}0 for DPPH radical-scavenging activity was 234 {+-} 8.9 {mu}g ml{sup 1}. The extracts showed weak nitric oxide-scavenging activity between 0.1 and 1.6 mg ml{sup -}1. The extracts showed weak Fe{sup 2}+ chelating ability. IC{sub 5}0 were 150 {+-} 13 {mu}g ml{sup -}1. The extracts also exhibited low antioxidant activity in the linoleic acid model but were capable of scavenging hydrogen peroxide in a concentration dependent manner. The total amount of phenolic compounds in each extract was determined as gallic acid equivalents and total flavonoid contents were calculated as quercetin equivalents from a calibration curve. Pharmacological effects may be attributed, at least in part, to the presence of phenols and flavonoids in the extracts. (Author) 40 refs.

  4. Neuropsychological outcomes of pediatric burn patients who sustained hypoxic episodes.

    Science.gov (United States)

    Rosenberg, Marta; Robertson, Carrie; Murphy, Kevin D; Rosenberg, Laura; Mlcak, Ronald; Robert, Rhonda S; Herndon, David N; Meyer, Walter J

    2005-11-01

    The neuropsychological outcomes of children who suffered hypoxic episodes following their burns are not completely understood and vary depending on the nature and severity of the episode. A retrospective review of youth that were admitted to this acute burn care facility over the past 20 years was conducted to identify the extent of cognitive and affective difficulties. Thirty-nine children who sustained hypoxic injuries related to their burns were compared with 21 controls that were matched for age, TBSA, and time of injury. Approximately a third of the children who survived from the hypoxia group continued to have long-term cognitive and emotional difficulties. For those who recovered reasonably well, no differences were found from the matched burned controls. These results probably underestimate the true extent of neuropsychological difficulties experienced by these youth given that detailed cognitive testing was not routinely performed. Prospective studies are needed to further characterize the full nature of difficulties and outcomes associated with burn related hypoxic injuries.

  5. Low-dose radiation suppresses Pokemon expression under hypoxic conditions.

    Science.gov (United States)

    Kim, Seung-Whan; Yu, Kweon; Shin, Kee-Sun; Kwon, Kisang; Hwang, Tae-Sik; Kwon, O-Yu

    2014-01-01

    Our previous data demonstrated that CoCl2-induced hypoxia controls endoplasmic reticulum (ER) stress-associated and other intracellular factors. One of them, the transcription factor Pokemon, was differentially regulated by low-dose radiation (LDR). There are limited data regarding how this transcription factor is involved in expression of the unfolded protein response (UPR) under hypoxic conditions. The purpose of this study was to obtain clues on how Pokemon is involved in the UPR. Pokemon was selected as a differentially expressed gene under hypoxic conditions; however, its regulation was clearly repressed by LDR. It was also demonstrated that both expression of ER chaperones and ER stress sensors were affected by hypoxic conditions, and the same results were obtained when cells in which Pokemon was up- or down-regulated were used. The current state of UPR and LDR research associated with the Pokemon pathway offers an important opportunity to understand the oncogenesis, senescence, and differentiation of cells, as well as to facilitate introduction of new therapeutic radiopharmaceuticals. PMID:24772825

  6. Transcriptome analysis of severe hypoxic stress during development in zebrafish

    Directory of Open Access Journals (Sweden)

    I.G. Woods

    2015-12-01

    Full Text Available Hypoxia causes critical cellular injury both in early human development and in adulthood, leading to cerebral palsy, stroke, and myocardial infarction. Interestingly, a remarkable phenomenon known as hypoxic preconditioning arises when a brief hypoxia exposure protects target organs against subsequent, severe hypoxia. Although hypoxic preconditioning has been demonstrated in several model organisms and tissues including the heart and brain, its molecular mechanisms remain poorly understood. Accordingly, we used embryonic and larval zebrafish to develop a novel vertebrate model for hypoxic preconditioning, and used this model to identify conserved hypoxia-regulated transcripts for further functional study as published in Manchenkov et al. (2015 in G3: Genes|Genomes|Genetics. In this Brief article, we provide extensive annotation for the most strongly hypoxia-regulated genes in zebrafish, including their human orthologs, and describe in detail the methods used to identify, filter, and annotate hypoxia-regulated transcripts for downstream functional and bioinformatic assays using the source data provided in Gene Expression Omnibus Accession GSE68473.

  7. Increased Neuronal Hypoxic Tolerance Induced by Repetitive Chemical Hypoxia

    Institute of Scientific and Technical Information of China (English)

    李红戈; 刘昌勤; 孙圣刚

    2002-01-01

    Summary: To investigate the effects of time interval and cumulative dosage of repetitive mild cellular hypoxia on shape of neurodegeneration and neuroprotection in mice, population spike amplitude (PSA) was measured during hypoxia and posthypoxic recovery in hippocampal slices from untreated control and mice pretreated in vivo with a single or repeatedly intraperitoneal injection of 3-nitropropi onate (3-NP). Posthypoxic recovery of PSA was dose-dependent in single pretreated slices, with maximal recovery on pretreatment attained with 20 mg/kg 3-NP (82±32%, P< 0. 01). Upon 5 and 9 treatments with 20 mg/kg 3-NP (dosage interval 3 days), PSA recovered to (38±9) % with the difference being not significant vs control group and (72±45) % with the difference being signif icant (P< 0. 05 to control, P<0.05 to 5 treatments), respectively. In contrast, with 2 days time interval, recovery after 5 and 9 treatments was (30±25) % and (16±14) %, respectively (without significant difference from control). Continued neuroprotection was also observed upon increase of dosage interval to 4 and 5 days. It was suggested that repetitive chemical hypoxia is a model for neu rodegenerative disease and continued neuroprotection depending on time interval between repetitive hypoxic episodes rather than cumulative dosage. At appropriate time intervals increased neuronal hy-poxic tolerance could be induced with number of hypoxic episodes.

  8. Hypoxic-Ischemic Neonatal Encephalopathy: Animal Experiments for Neuroprotective Therapies

    Directory of Open Access Journals (Sweden)

    Hiroshi Sameshima

    2013-01-01

    Full Text Available Hypoxic-ischemic neonatal encephalopathy and ensuing brain damage is still an important problem in modern perinatal medicine. In this paper, we would like to share some of the results of our recent studies on neuroprotective therapies in animal experiments, as well as some literature reviews. From the basic animal studies, we have now obtained some possible candidates for therapeutic measures against hypoxic-ischemic neonatal encephalopathy. For example, they are hypothermia, rehabilitation, free radical scavenger, neurotrophic factors and growth factors, steroid, calcium channel blocker, vagal stimulation, some anti apoptotic agents, pre- and post conditioning, antioxidants, cell therapy with stem cells, modulators of K(+-ATP channels, and so on. Whether combination of these therapies may be more beneficial than any single therapy needs to be clarified. Hypoxia-ischemia is a complicated condition, in which the cause, severity, and time-course are different in each case. Likewise, each fetus has its own inherent potentials such as adaptation, preconditioning-tolerance, and intolerance. Therefore, further extensive studies are required to establish an individualized strategy for neuroprotection against perinatal hypoxic-ischemic insult.

  9. Neurobehavioral impairments, generation of oxidative stress and release of pro-apoptotic factors after chronic exposure to sulphur mustard in mouse brain

    International Nuclear Information System (INIS)

    Recent global events have focused attention on the potential threat of international and domestic chemical terrorism, as well as the possibility of chemical warfare proliferation. Sulphur mustard (SM) is one of the potent chemical warfare agents (CWA), which initiates a cascade of events that converge on the redox mechanisms common to brain injury. The present study was designed to examine the effects of chronic SM exposure on neurobehavioral impairments, mitochondrial oxidative stress in male Swiss Albino mice and its role in inducing apoptotic neuronal cell death. The animals were divided into four groups (control, low, medium and high dose) of 5 animals each. Exposure to SM was given percutaneously daily for 12 weeks. The results demonstrated impairment in neurobehavioral indices viz. rota rod, passive avoidance and water maze tests in a dose dependent manner. There was a significant increase in lipid peroxidation and protein carbonyl content whereas, decrease in the activity of manganese superoxide dismutase (MnSOD), glutathione reductase and glutathione peroxidase suggesting impaired antioxidant defense system. Immunoblotting of cytochrome c, Bcl-2, Bax and activation of caspase-3 suggest induction of apoptosis in a dose dependent manner. Finally, increased p53 expression suggests that it may target the mitochondrial pathway for inducing apoptosis in response to DNA damage signals. In conclusion, chronic SM exposure may have the potential to generate oxidative stress which may trigger the release of cytochrome c as well as caspase-3 activation in neurons leading to cell death by apoptosis in a dose dependent manner which may in the end be responsible for the disruption of cognitive functions in mice.

  10. The express of PTP-1 B and IRS-1 in liver cells of rats during chronic intermittent hypoxic%PTP-1B 及 IRS-1在慢性间歇低氧大鼠肝细胞中的表达

    Institute of Scientific and Technical Information of China (English)

    赵勇; 任寿安; 蔡月伟

    2015-01-01

    目的:探讨慢性间歇低氧(CIH)对大鼠肝细胞蛋白酪氨酸磷酸酶-1B(protein tyrosine phosphatase-1B,PTP-1B)及胰岛素受体底物-1(insulin receptor substrate-1,IRS-1)蛋白表达量的影响及其导致胰岛素抵抗发生的可能机制。方法选取健康雄性 SD 大鼠24只,按随机数字表法分为正常对照组(NC 组)、慢性间歇低氧4周组(CIH4组)、慢性间歇低氧8周组(CIH8组),每组8只。NC 组无间歇低氧暴露正常饲养,CIH4组及 CIH8组于上午9时至下午5时放入间歇低氧仓暴露于间歇低氧环境中,舱内最低氧浓度为6%~7%。分别于第4周及第8周检测大鼠空腹血糖及空腹胰岛素水平,用稳态模型胰岛素抵抗指数(HOMA-IR)以及胰岛素敏感指数(insulin sensitive index,ISI)评价胰岛素抵抗, SABC 法免疫组织化学试剂盒检测 CIH 大鼠肝细胞 PTP-1B 及 IRS-1蛋白表达,以平均灰度值表示PTP-1B 及 IRS-1的蛋白表达量,并做统计学分析。结果与 NC 组比较,CIH4组及 CIH8组空腹血糖、空腹胰岛素及 HOMA-IR 升高,ISI 降低,差异有统计学意义(P <0.05),且 CIH8组更为显著;与 NC 组相比较,CIH4组及 CIH8组 PTP-1B 蛋白表达增加,IRS-1蛋白表达减少,差异有统计学意义(P <0.05),Pearson 相关分析显示,HOMA-IR 与 PTP-1B 平均灰度值呈负相关、与 IRS-1平均灰度值呈正相关;ISI 与 PTP-1B 平均灰度值呈正相关、与 IRS-1平均灰度值呈负相关。结论①CIH 暴露使大鼠空腹血糖及胰岛素水平升高且发生胰岛素抵抗,随着 CIH 暴露时间的延长,胰岛素抵抗程度加重。②CIH 导致大鼠肝细胞 PTP-1B 蛋白表达增加,IRS-1蛋白表达减少,PTP-1B 及 IRS-1可能共同参与了 CIH 大鼠胰岛素抵抗的发生发展。%Objective To investigate the effects of chronic intermittent hypoxia on the expression of PTP-1B and IRS-1 and the possible mechanism of insulin resistance caused by chronic intermittent hypoxia.Methods According to the

  11. Mouse adhalin

    DEFF Research Database (Denmark)

    Liu, L; Vachon, P H; Kuang, W;

    1997-01-01

    analyze the biological roles of adhalin, we cloned the mouse adhalin cDNA, raised peptide-specific antibodies to its cytoplasmic domain, and examined its expression and localization in vivo and in vitro. The mouse adhalin sequence was 80% identical to that of human, rabbit, and hamster. Adhalin was...... specifically expressed in striated muscle cells and their immediate precursors, and absent in many other cell types. Adhalin expression in embryonic mouse muscle was coincident with primary myogenesis. Its expression was found to be up-regulated at mRNA and protein levels during myogenic differentiation in...

  12. 慢性间断性缺氧对帕金森病模型小鼠认知功能的影响%Effect of chronic intermittent hypoxia on the cognitive function of mouse model for Parkinson's disease

    Institute of Scientific and Technical Information of China (English)

    刘海林; 徐江涛; 宋永斌; 杨俊; 许永华; 余伍忠; 李景春; 张子彦

    2011-01-01

    Objective: To investigate the effect of chronic intermittent hypoxia on cognitive function in the mouse model of Parkinsons disease.Methods: Forty-four six-week-old male C57BL/6 mice were randomly divided into Paraquat (PQ) group, chronic intermittent hypoxia (CIH) group, PQ + CIH group and control group.Hypoxia-reoxygen device simulates the process of CIH.Meanwhile, intraperitoneal injection of PQ induced the mouse model of Parkinson's disease.Learning and memory function were evaluated by Y-type maze and step-down test.Acetylcholine (Ach) level and acetyl cholinesterase (Ach E) activity in hippocampus of mice were detected by colorimetric method.Results: Comparing with PQ group, PQ + CIH group had an extended total reaction time (TRT) (F <0.01) and an increased error number (EN) (P <0.05) of learning and memory both in Y-type maze test and step-down test.Comparing with PQ group, the Ach level and Ach E activity of mice hippocampus in PQ + CIH group were significantly decreased ( P < 0.05 ).Conclusion: CIH increased the degree of cognition decline in PQ induced mouse model of PD, which may be related with the decrease of Ach level and Ach E activity in hippocampus.%目的:探讨慢性间断性缺氧(CIH)对帕金森病模型小鼠认知功能的影响.方法:44只雄性6周龄C57BL/6小鼠,随机分为百草枯组、CIH组、百草枯加CIH组和对照组.用缺氧-复氧循环装置模拟 CIH 过程,通过腹腔注射百草枯诱导制备帕金森病模型小鼠.使用Y型-电迷宫和跳台实验评价小鼠学习记忆能力;化学比色法测定小鼠海马乙酰胆碱含量和乙酰胆碱酯酶活性.结果:3个实验组的学习记忆成绩、乙酰胆碱含量和乙酰胆碱酯酶活性均明显低于对照组(P均<0.01),其中百草枯加CIH组明显低于百草枯组与CIH组(P均<0.05),百草枯组与CIH组比较差异无统计学意义(P均>0.05).结论:CIH加重了百草枯所致帕金森病模型小鼠认知功能下降程度,可

  13. microRNA regulation of the embryonic hypoxic response in Caenorhabditis elegans

    OpenAIRE

    Kagias, Konstantinos; Pocock, Roger

    2015-01-01

    Layered strategies to combat hypoxia provide flexibility in dynamic oxygen environments. Here we show that multiple miRNAs are required for hypoxic survival responses during C. elegans embryogenesis. Certain miRNAs promote while others antagonize the hypoxic survival response. We found that expression of the mir-35 family is regulated by hypoxia in a HIF-1-independent manner and loss of mir-35–41 weakens hypoxic survival mechanisms in embryos. In addition, correct regulation of the RNA bindin...

  14. A novel transgenic mouse model of growth plate dysplasia reveals that decreased chondrocyte proliferation due to chronic ER stress is a key factor in reduced bone growth

    Directory of Open Access Journals (Sweden)

    Benedetta Gualeni

    2013-11-01

    Disease mechanisms leading to different forms of chondrodysplasia include extracellular matrix (ECM alterations and intracellular stress resulting in abnormal changes to chondrocyte proliferation and survival. Delineating the relative contribution of these two disease mechanisms is a major challenge in understanding disease pathophysiology in genetic skeletal diseases and a prerequisite for developing effective therapies. To determine the influence of intracellular stress and changes in chondrocyte phenotype to the development of chondrodysplasia, we targeted the expression of the G2320R mutant form of thyroglobulin to the endoplasmic reticulum (ER of resting and proliferating chondrocytes. Previous studies on this mutant protein have shown that it induces intracellular aggregates and causes cell stress and death in the thyroid gland. The expression and retention of this exogenous mutant protein in resting and proliferating chondrocytes resulted in a chronic cell stress response, growth plate dysplasia and reduced bone growth, without inducing any alterations to the architecture and organization of the cartilage ECM. More significantly, the decreased bone growth seemed to be the direct result of reduced chondrocyte proliferation in the proliferative zone of growth plates in transgenic mice, without transcriptional activation of a classical unfolded protein response (UPR or apoptosis. Overall, these data show that mutant protein retention in the ER of resting and proliferative zone chondrocytes is sufficient to cause disrupted bone growth. The specific disease pathways triggered by mutant protein retention do not necessarily involve a prototypic UPR, but all pathways impact upon chondrocyte proliferation in the cartilage growth plate.

  15. NKG2D mediates NK cell hyperresponsiveness and influenza-induced pathologies in a mouse model of chronic obstructive pulmonary disease.

    Science.gov (United States)

    Wortham, Brian W; Eppert, Bryan L; Motz, Greg T; Flury, Jennifer L; Orozco-Levi, Mauricio; Hoebe, Kasper; Panos, Ralph J; Maxfield, Melissa; Glasser, Stephan W; Senft, Albert P; Raulet, David H; Borchers, Michael T

    2012-05-01

    Chronic obstructive pulmonary disease (COPD) is characterized by peribronchial and perivascular inflammation and largely irreversible airflow obstruction. Acute disease exacerbations, due frequently to viral infections, lead to enhanced disease symptoms and contribute to long-term progression of COPD pathology. Previously, we demonstrated that NK cells from cigarette smoke (CS)-exposed mice exhibit enhanced effector functions in response to stimulating cytokines or TLR ligands. In this article, we show that the activating receptor NKG2D is a key mediator for CS-stimulated NK cell hyperresponsiveness, because CS-exposed NKG2D-deficient mice (Klrk1(-/-)) did not exhibit enhanced effector functions as assessed by cytokine responsiveness. NK cell cytotoxicity against MHC class I-deficient targets was not affected in a COPD model. However, NK cells from CS-exposed mice exhibit greater cytotoxic activity toward cells that express the NKG2D ligand RAET1ε. We also demonstrate that NKG2D-deficient mice exhibit diminished airway damage and reduced inflammation in a model of viral COPD exacerbation, which do not affect viral clearance. Furthermore, adoptive transfer of NKG2D(+) NK cells into CS-exposed, influenza-infected NKG2D-deficient mice recapitulated the phenotypes observed in CS-exposed, influenza-infected wild-type mice. Our findings indicate that NKG2D stimulation during long-term CS exposure is a central pathway in the development of NK cell hyperresponsiveness and influenza-mediated exacerbations of COPD. PMID:22467655

  16. Hypothalamic Proteomic Analysis Reveals Dysregulation of Glutamate Balance and Energy Metabolism in a Mouse Model of Chronic Mild Stress-Induced Depression.

    Science.gov (United States)

    Rao, Chenglong; Shi, Haiyang; Zhou, Chanjuan; Zhu, Dan; Zhao, Mingjun; Wang, Ziye; Yang, Yongtao; Chen, Jin; Liao, Li; Tang, Jianyong; Wu, You; Zhou, Jian; Cheng, Ke; Xie, Peng

    2016-09-01

    Hypothalamus-pituitary-adrenal (HPA) axis hyperactivity is observed in many patients suffering from depression. However, the mechanism underlying the dysfunction of the HPA axis is not well understood. Moreover, dysfunction of the hypothalamus, the key brain region of the HPA axis, has not been well-explored. The aim of our study was to examine possible alterations in hypothalamus protein expression in a model of depression using proteomic analysis. In order to achieve this aim, mice were exposed to chronic unpredictable mild stress (CUMS), as the paradigm results in hyperactivity of the HPA axis. Differential protein expression between the hypothalamic proteomes of CUMS and control mice was then assessed through two-dimensional electrophoresis followed by matrix-assisted laser desorption ionization-time of flight-tandem mass spectrometry. Thirty-seven proteins with a threshold of a 1.5-fold change and a p value ≤0.05 were identified as being differentially expressed between CUMS and control mice, and were quantified for bioinformatics analysis. Glycometabolism, citrate cycle (TCA cycle) and oxidation respiratory chain were found to have changed significantly. Glial fibrillary acidic protein and glutamine synthetase were further validated by Western Blot. Our results demonstrated that CUMS mice exhibited a dramatic protein change both in glutamate metabolism and energy mobilization, which may shed some light on the role of the hypothalamus in the pathology of stress-induced depression. PMID:27230881

  17. Chronic Diarrhea

    Science.gov (United States)

    ... infections that cause chronic diarrhea be prevented? Chronic Diarrhea What is chronic diarrhea? Diarrhea that lasts for more than 2-4 ... represent a life-threatening illness. What causes chronic diarrhea? Chronic diarrhea has many different causes; these causes ...

  18. Pulmonary administration of 1,25-dihydroxyvitamin D3 to the lungs induces alveolar regeneration in a mouse model of chronic obstructive pulmonary disease.

    Science.gov (United States)

    Horiguchi, Michiko; Hirokawa, Mai; Abe, Kaori; Kumagai, Harumi; Yamashita, Chikamasa

    2016-07-10

    Chronic obstructive pulmonary disease (COPD) is a progressive respiratory disease with several causes, including smoking, and no curative therapeutic agent is available, particularly for destructive alveolar lesions. In this study, we investigated the differentiation-inducing effect on undifferentiated lung cells (Calu-6) and the alveolar regenerative effect of the active vitamin 1,25-dihydroxy vitamin D3 (VD3) with the ultimate goal of developing a novel curative drug for COPD. First, the differentiation-inducing effect of VD3 on Calu-6 cells was evaluated. Treatment with VD3 increased the proportions of type I alveolar epithelial (AT-I) and type II alveolar epithelial (AT-II) cells constituting alveoli in a concentration- and treatment time-dependent manner, demonstrating the potent differentiation-inducing activity of VD3 on Calu-6 cells. We thus administered VD3 topically to the mice lung using a previously developed intrapulmonary administration via self-inhalation method. To evaluate the alveolus-repairing effect of VD3, we administered VD3 intrapulmonarily to elastase-induced COPD model mice and computed the mean distance between the alveolar walls as an index of the extent of alveolar injury. Results showed significant decreases in the alveolar wall distance in groups of mice that received 0.01, 0.1, and 1μg/kg of intrapulmonary VD3, revealing excellent alveolus-regenerating effect of VD3. Furthermore, we evaluated the effect of VD3 on improving respiratory function using a respiratory function analyzer. Lung elasticity and respiratory competence [forced expiratory volume (FEV) 1 s %] are reduced in COPD, reflecting advanced emphysematous changes. In elastase-induced COPD model mice, although lung elasticity and respiratory competence were reduced, VD3 administered intrapulmonarily twice weekly for 2weeks recovered tissue elastance and forced expiratory volume in 0.05s to the forced vital capacity, which are indicators of lung elasticity and respiratory

  19. Sirtuin 6 protects the heart from hypoxic damage

    Energy Technology Data Exchange (ETDEWEB)

    Maksin-Matveev, Anna; Kanfi, Yariv [The Mina and Everard Goodman, Faculty of Life Sciences, Bar-Ilan University, Ramat Gan 52900 (Israel); Hochhauser, Edith [The Laboratory of the Department of Cardiothoracic Surgery, Felsenstein Medical Research Center, Rabin Medical Center, Petach Tikva (Israel); Isak, Ahuva; Cohen, Haim Y. [The Mina and Everard Goodman, Faculty of Life Sciences, Bar-Ilan University, Ramat Gan 52900 (Israel); Shainberg, Asher, E-mail: asher.shainberg@gmail.com [The Mina and Everard Goodman, Faculty of Life Sciences, Bar-Ilan University, Ramat Gan 52900 (Israel)

    2015-01-01

    Sirtuin 6 (SIRT6) is a protein associated with prolonged life expectancy. We investigated whether life extension is associated with cardioprotection against hypoxia. The proposed study is to develop approaches to reduce hypoxic damage through the use of the sirtuin pathway and to elucidate the mechanism involved. For that purpose we subjected cardiomyocytes from transgenic mice (TG) with over-expression of SIRT6, to hypoxic stress in cell cultures. We hypothesized that cardiomyocytes from transgenic mice subjected to prolonged hypoxia may release survival factors or fewer damage markers to protect them from hypoxic stress compared with wild type (WT) mice. Lactate dehydrogenase (LDH) and creatine kinase (CK) released to the medium and propidium iodide (PI) binding, were markedly decreased following hypoxia in TG cardiomyocytes. The protective mechanism of SIRT6 over-expression includes the activation of pAMPKα pathway, the increased protein level of B-cell lymphoma 2 (Bcl2), the inhibition of nuclear factor kappa-light-chain-enhancer of activated B cells (NFκB), the decrease of reactive oxygen species (ROS) and the reduction in the protein level of phospho-protein kinase B (pAkt) during hypoxia. Together, all these processes impede the necrosis/apoptosis pathways leading to the improved survival of cardiomyocytes following hypoxia, which might explain life extension. - Highlights: • Sirtuin 6 is a protein associated with prolonged life expectancy. • Over-expression of sirtuin 6 protects cardiocytes from hypoxia and oxidative stress. • Over-expression of sirtuin 6 activates the pAMPKα pathway and the Bcl2 expression. • Over-expression of sirtuin 6 decreases ROS formation and pAkt level during hypoxia. • These pathways protect cardiocytes from hypoxia and might explain lifespan extension.

  20. Estetrol attenuates neonatal hypoxic-ischemic brain injury.

    Science.gov (United States)

    Tskitishvili, Ekaterine; Nisolle, Michelle; Munaut, Carine; Pequeux, Christel; Gerard, Celine; Noel, Agnes; Foidart, Jean-Michel

    2014-11-01

    Estetrol (E4) is a recently described natural estrogen with four hydroxyl-groups that is synthesized exclusively during pregnancy by the human fetal liver. It has important antioxidative activity. The aim of the present study was to define the importance of E4 in the attenuation of neonatal hypoxic-ischemic encephalopathy. Antioxidative effect of 650μM, 3.25mM and 6.5mM E4 on primary hippocampal cell cultures was studied before/after H202-induced oxidative stress. To examine oxidative stress and cell viability, lactate dehydrogenase activity and cell proliferation colorimetric assays were performed. To study the neuroprotective and therapeutic effects of E4 in vivo neonatal hypoxic-ischemic encephalopathy model of 7-day-old newborn rat pups was used. The neuroprotective and therapeutic effects of estetrol before/after hypoxic-ischemic insult was studied in 1mg/kg/day, 5mg/kg/day, 10mg/kg/day, 50mg/kg/day E4 pretreated/treated groups and compared with the sham and the vehicle treated groups. The body temperature of the rat pups was examined along with their body and brain weights. Brains were studied at the level of the hippocampus and cortex. Intact cell counting and expressions of microtubule-associated protein-2, doublecortin and vascular-endothelial growth factor were evaluated by histo- and immunohistochemistry. ELISAs were performed on blood samples to detect concentrations of S100B and glial fibrillary acidic protein as brain damage markers. This work reveals for the first time that E4 significantly decreases LDH activity and enhances cell proliferation in primary hippocampal neuronal cell cultures in vitro, and decreases the early gray matter loss and promotes neuro- and angiogenesis in vivo. PMID:25079370

  1. Hypoxic regulation of the NKG2D ligand, H60

    OpenAIRE

    Krishnamurthy, Siddharth Ravindran

    2009-01-01

    Hypoxia in the context of cancer has been well studied as it has been shown that tumors that are in hypoxic conditions tend to become malignant or metastatic. There is evidence that hypoxia is able to modulate tumor immunogenicity, however this phenomenon has not been well characterized. Here, we look at the effects of hypoxia on tumor immunogenicity from the perspective of NK cell recognition. We find that hypoxia decreases the expression of the NKG2D ligand, H60 post-transcriptionally but n...

  2. Nitric oxide metabolites in goldfish under normoxic and hypoxic conditions

    DEFF Research Database (Denmark)

    Hansen, Marie N.; Jensen, Frank Bo

    2010-01-01

    ) in multiple tissues of a non-mammalian vertebrate (goldfish) under normoxic and hypoxic conditions. NO metabolites were measured in blood (plasma and red cells) and heart, brain, gill, liver, kidney and skeletal muscle, using highly sensitive reductive chemiluminescence. The severity of the chosen hypoxia...... to and below the critical PO2] for two days caused large decreases in plasma nitrite and nitrate, which suggests reduced NOS activity and increased nitrite/nitrate utilization or loss. Tissue NO metabolites were largely maintained at their tissue-specific values under hypoxia, pointing at nitrite transfer from...

  3. Cytosolic phospholipase A2 in hypoxic pulmonary vasoconstriction

    OpenAIRE

    Ichinose, Fumito; Ullrich, Roman; Sapirstein, Adam; Jones, Rosemary C; Bonventre, Joseph V.; Serhan, Charles N.; Bloch, Kenneth D.; Zapol, Warren M.

    2002-01-01

    Cytosolic phospholipase A2 (cPLA2) releases arachidonic acid (AA) from phospholipids in cell membranes. To assess the role of cPLA2 in hypoxic pulmonary vasoconstriction (HPV), we measured the increase in left lung pulmonary vascular resistance (LPVR) before and during hypoxia produced by left main stem bronchus occlusion (LMBO) in mice with and without a targeted deletion of the PLA2g4a gene that encodes cPLA2α. LMBO increased LPVR in cPLA2α+/+ mice but not in cPLA2α–/– mice. cPLA2α+/+ mice ...

  4. Impact of the chronic arsenic poisoning on the ultraturcture of adult mouse brain temporal lobe cortex%慢性砷中毒对成年小鼠大脑皮质颞叶超微结构的影响

    Institute of Scientific and Technical Information of China (English)

    花伟; 臧贵勇

    2015-01-01

    Objective To observe the changes of the ultrastructure of the temporal lobe cortex for the brains of these mouse with chronic arsenicpoisoning ,to explore the mechanism of arsenic toxicity on the brain .Method 60 healthy adult Kunming mouse ( 30 male and 30 female) were selected and divided into control group ,low and high dose groups . There were 20 mouse in each group . The dye arsenic group respectively with distilled water , 1/5LD50 ,1/50LD50 ,As2 O3 solution to fill the stomach ,for three consecutive months .After building ,canister , based on the determination of arsenic in groups of mice brain ,Nepal’s dyeing were used to observe the cerebral cor‐tex of temporal morphology change ,transmission electronmicroscope to observe the changes of the ultrastructure of the cerebral cortex temporal lobe in mice .Result It might be the type the type of arsenic content in the cerebral cor‐tex was significantly higher than the control group (P<0 .05) .It was observed the decrease in the number of infec‐ted each cortical neurons ,shape was irregular ,intracytoplasmic austenite reduced .It was observed under electron microscope the prion edema groups of nerve cells ,organelles decreased ,mitochondrial cristae fracture and cavity . Conclusion Arsenic poisoning can cause nerve cell pathology and ultrastructure change of cerebral cortex .%目的:观察慢性砷中毒对小鼠大脑皮质颞叶超微结构的改变,探讨砷对大脑的毒性机制。方法选取健康成年昆明小鼠60只,雌雄各半,分为对照组、慢性砷中毒低、高剂量组,每组20只,各染砷组分别以蒸馏水、1/5LD50、1/50 LD50的As2 O3溶液灌胃,连续3个月。经造模、染毒、取材后,测定各组小鼠大脑中砷含量,采用尼氏染色观察大脑皮质颞叶形态学改变,透射电镜观察小鼠大脑皮质颞叶超微结构的变化。结果(1)染毒各组小鼠大脑皮质中砷含量明显高于对照组(P<0.05);(2)

  5. 二十碳五烯酸对小鼠心脏移植慢性排斥反应的影响%Anti-chronic rejection effects of EPA in mouse heterotopic heart transplantation model

    Institute of Scientific and Technical Information of China (English)

    周诚; 叶平; 李军; 夏家红

    2011-01-01

    目的 观察二十碳五烯酸(EPA)对于慢性排斥反应的影响,并探讨其可能的作用机制.方法 建立近交系BALB/C(H-2d)至C57BL/6(H-2b)小鼠心脏腹腔异位移植模型,通过腹腔注射单克隆CD4抗体及CD40L抗体建立慢性排斥反应模型.设立对照组(NS)、慢排组(术后0、1、5、10 d腹腔注射抗CD4单克隆抗体100μg/d,术后0、2、4 d腹腔注射抗CD40L单克隆抗体200 μg/d)和EPA组[在慢排组的基础上EPA 100 mg/(kg·d)灌胃].术后60 d,EVG染色了解血管病变.利用Real-Time聚合酶链反应(PGR)检测各组移植物慢排相关细胞因子转化生长因子(TGF)-β、白细胞介素(IL)-17的mRNA水平,组织化学研究EPA作用受体PPARy的表达以及TGF-β通路重要分子Smad3活化情况.结果 利用CD4抗体及CD40L抗体成功建立慢性排斥反应模型,出现典型的血管病变.联合利用EPA明显减轻血管狭窄[闭塞(18±3)%比(59±7)%,P<0.05]、并下调局部TGF-β、IL-17表达(TGF-β:12.0±2.5比4.0±0.9;IL-17:0.60±0.09比0.10±0.02;P<0.05).同时上调PPARγ的表达[(25±7)比(2±0.5)个/高倍视野;P<0.05],并抑制Smad3的磷酸化[(30±5)比(10±3)个/高倍视野;P<0.05].结论 EPA可以激活和上调供心PPARγ的表达,明显减轻慢性排斥反应血管病变.%Objective To investigate the anti-chronic rejection effects of eicosapentaenoic acid (EPA) in a mouse fully mismatched cardiac transplantation model and the possible mechanism.Methods Heterotopic heart transplantation of male BALB/C(H-2d) mouse to C57BL/6(H-2b) mouse were performed.24 recipients were divided into 3 groups at random:group A ( treated with saline as control,n =8) ;group B recipients were treated with anti-CD40L mAb (200 μg intraperitoneally infusion on the day 0,2 and 4) and CD4 mAb (100μg intraperitoneally infusion on the day 0,1,5 and 10) ;GroupC (CD4 & CD40L mAb combined with EPA by gavage).The cardiac grafts were harvested on the 60th day after transplantation with HE

  6. Excess post-hypoxic oxygen consumption is independent from lactate accumulation in two cyprinid fishes

    DEFF Research Database (Denmark)

    Genz, J.; Jyde, M.B.; Svendsen, Jon Christian;

    2013-01-01

    Carassius carassius responds to hypoxic conditions by conversion of lactate into ethanol, which is excreted over the gills. However, a closely related species, Cyprinus carpio, does not possess the ability to produce ethanol and would be expected to accumulate lactate during hypoxic exposure. Whi...

  7. [Hypoxic brain injuries notified to the Danish Patient Insurance Association during 1992-2004. Secondary publication

    DEFF Research Database (Denmark)

    Bock, J.; Christoffersen, J.K.; Hedegaard, M.;

    2008-01-01

    We investigated the files of the Danish Patient Insurance Association for newborns suffering from hypoxic brain injuries. From 1992 to 2004, a total of 127 approved claims concerning peripartum hypoxic injury were registered. Thirty-eight newborns died and the majority of the 89 surviving childre...

  8. Correlation between drug uptake and selective toxicity of porfiromycin to hypoxic EMT6 cells.

    Science.gov (United States)

    Keyes, S R; Rockwell, S; Sartorelli, A C

    1987-11-01

    Mitomycin C and its methylated analogue porfiromycin (Por) have significant potential as adjuncts to regimens presently used for treating solid tumors because of their preferential toxicity to cells existing in an hypoxic environment. An understanding of the factors producing the differential activity of these drugs under aerobic and hypoxic conditions would facilitate the development of new agents of this class. Previous studies have focused on the enzymes that reductively activate the mitomycins and on the interaction of these drugs with DNA; none of these studies has fully explained the differences in cytotoxicity observed under hypoxic and aerobic conditions. The present investigation demonstrates that the rate of Por uptake is directly correlated with cytotoxicity under both aerobic and hypoxic conditions. Uptake of Por into hypoxic cells is more rapid than into aerobic cells at equal drug concentrations. Hypoxic cells also accumulate drug in concentrations well in excess of those in the extracellular medium; this is apparently a reflection of drug sequestration in these cells. This sequestration of Por, which affects the rate and extent of uptake in hypoxic cells, does not take place in aerobic cells. The failure of aerobic cells to sequester drug is evidenced by the very rapid efflux of Por from these cells upon removal of extracellular Por and by the fact that aerobic cells attain a state of equilibrium between the intracellular and extracellular drug concentrations. The findings demonstrate that differences in the uptake and retention of Por are associated with the preferential toxicity of Por to hypoxic cells. PMID:3664473

  9. RADIOPHARMACEUTICALS FOR IMAGING OF HYPOXIC TUMORS: A REVIEW

    Directory of Open Access Journals (Sweden)

    Chaitanya Prasad Meher

    2012-11-01

    Full Text Available Radiopharmaceuticals are drugs containing a radionuclide and are used routinely in nuclear medicine for the diagnosis and therapy of various diseases. The mechanism of localization of the radiopharmaceutical in different organs provides the clue for designing of the agent meant for a specific organ or pathway. Various agent like F-18, Cu-64/67, I-123, and Tc-99m are used as imaging of hypoxic tumors. Of these, F-18-fluoromisonidazole and I-123-iodoazomycin arabinoside (IAZA have been most widely studied clinically. Non-nitro-containing bioreductive complexes, such as the Cu-60/62/64 thiosemicarbazone ATSM and Tc-99m butylene amineoxime (BnAO or HL91, have also been evaluated. In particular, I-123-IAZA and Cu-60-ATSM have shown correlation with response to radiotherapy in preliminary clinical studies. However, more preclinical studies comparing imaging with validated invasive methods and clinical studies with outcome measures are required. Nuclear medicine is poised to play an important role in optimizing the therapy of patients with hypoxic tumors. The present review is concern with the various radiopharmaceuticals used for imaging of hypoxia.

  10. Plasticity in the Neonatal Brain following Hypoxic-Ischaemic Injury

    Directory of Open Access Journals (Sweden)

    Eridan Rocha-Ferreira

    2016-01-01

    Full Text Available Hypoxic-ischaemic damage to the developing brain is a leading cause of child death, with high mortality and morbidity, including cerebral palsy, epilepsy, and cognitive disabilities. The developmental stage of the brain and the severity of the insult influence the selective regional vulnerability and the subsequent clinical manifestations. The increased susceptibility to hypoxia-ischaemia (HI of periventricular white matter in preterm infants predisposes the immature brain to motor, cognitive, and sensory deficits, with cognitive impairment associated with earlier gestational age. In term infants HI causes selective damage to sensorimotor cortex, basal ganglia, thalamus, and brain stem. Even though the immature brain is more malleable to external stimuli compared to the adult one, a hypoxic-ischaemic event to the neonate interrupts the shaping of central motor pathways and can affect normal developmental plasticity through altering neurotransmission, changes in cellular signalling, neural connectivity and function, wrong targeted innervation, and interruption of developmental apoptosis. Models of neonatal HI demonstrate three morphologically different types of cell death, that is, apoptosis, necrosis, and autophagy, which crosstalk and can exist as a continuum in the same cell. In the present review we discuss the mechanisms of HI injury to the immature brain and the way they affect plasticity.

  11. Plasticity in the Neonatal Brain following Hypoxic-Ischaemic Injury.

    Science.gov (United States)

    Rocha-Ferreira, Eridan; Hristova, Mariya

    2016-01-01

    Hypoxic-ischaemic damage to the developing brain is a leading cause of child death, with high mortality and morbidity, including cerebral palsy, epilepsy, and cognitive disabilities. The developmental stage of the brain and the severity of the insult influence the selective regional vulnerability and the subsequent clinical manifestations. The increased susceptibility to hypoxia-ischaemia (HI) of periventricular white matter in preterm infants predisposes the immature brain to motor, cognitive, and sensory deficits, with cognitive impairment associated with earlier gestational age. In term infants HI causes selective damage to sensorimotor cortex, basal ganglia, thalamus, and brain stem. Even though the immature brain is more malleable to external stimuli compared to the adult one, a hypoxic-ischaemic event to the neonate interrupts the shaping of central motor pathways and can affect normal developmental plasticity through altering neurotransmission, changes in cellular signalling, neural connectivity and function, wrong targeted innervation, and interruption of developmental apoptosis. Models of neonatal HI demonstrate three morphologically different types of cell death, that is, apoptosis, necrosis, and autophagy, which crosstalk and can exist as a continuum in the same cell. In the present review we discuss the mechanisms of HI injury to the immature brain and the way they affect plasticity. PMID:27047695

  12. Evaluation of 80 Term Neonates with Hypoxic Ischemic Encephalopathy

    Directory of Open Access Journals (Sweden)

    Selahattin Katar

    2007-01-01

    Full Text Available This study aimed to review the etiology, clinical - laboratory features and mortality rate of term 80 neonates with perinatal asphyxia admitted to our neonatal unit between January 2005-April 2006. The sex distribution was 24 (%30 female and 56 (% 70 male. The mean gestational age was 38.6±1.3 weeks and weight 3156±561 gram. Of the patients % 46.25 were delivered with a cesarean section and % 53.75 with spontaneous vaginal delivery. The etiologic factors for hypoxic ischemic encephalopathy were % 31.25 force delivery, meconium aspiration, and % 66.25 preeclampsia, eclampsia and diabetic mother’s infant. The distribution of patients according to HIE statging system (Sarnat&Sarnat were as follows: 33 patients (% 41.25 in stage 1, 20 (% 25 in stage 2 and 27 (% 33.75 in stage 3. Seizures were observed in % 33.75 of patients. The mean duration of hospital stay was 10.6±7.7 days for the surviving patients and 4.2±3.4 days for patients who died. Except from central nervous system, liver and kidney were the most involved organs.Perinatal asphyxia remains to be leading cause of neonatal mortality. Hypoxic ischemic encephalopathy is a common newborn problem and cause important mortality and morbidity where low-social –cultural –education conditions with in regions.

  13. The G. L. Brown Prize Lecture. Hypoxic regulation of ion channel function and expression.

    Science.gov (United States)

    Peers, Chris

    2002-07-01

    Acute hypoxia regulates the activity of specific ion channels in a rapid and reversible manner. Such effects underlie appropriate cellular responses to hypoxia which are designed to initiate cardiorespiratory reflexes and contribute importantly to other tissue responses, all of which are designed to improve tissue O2 supply. These responses include excitation of chemoreceptors as well as pulmonary vasoconstriction and systemic vasodilatation. However, such responses may also contribute to the adverse responses to hypoxia, such as excitotoxicity in the central nervous system. Whilst numerous ion channel types are known to be modulated by acute hypoxia, the nature of the O2 sensor in most tissues remains to be identified. Prolonged (chronic) hypoxia regulates functional expression of ion channels, and so remodels excitability of various cell types. Whilst this may contribute to adaptive responses such as high-altitude acclimatization, such altered channel expression may also contribute to the onset of pathological disorders, including Alzheimer's disease. Indeed, evidence is emerging that production of pathological peptides associated with Alzheimer's disease is increased during prolonged hypoxia. Such effects may account for the known increased incidence of this disease in patients who have previously endured hypoxic episodes, such as congestive heart failure and stroke. Identification of the mechanisms coupling hypoxia to the increased production of these peptides is likely to be of therapeutic benefit. PMID:12392105

  14. Disturbed hypoxic responses as a pathogenic mechanism of diabetic foot ulcers.

    Science.gov (United States)

    Catrina, Sergiu-Bogdan; Zheng, Xiaowei

    2016-01-01

    Diabetic foot ulceration (DFU) is a chronic complication of diabetes that is characterized by impaired wound healing in the lower extremities. DFU remains a major clinical challenge because of poor understanding of its pathogenic mechanisms. Impaired wound healing in diabetes is characterized by decreased angiogenesis, reduced bone marrow-derived endothelial progenitor cell (EPC) recruitment, and decreased fibroblast and keratinocyte proliferation and migration. Recently, increasing evidence has suggested that increased hypoxic conditions and impaired cellular responses to hypoxia are essential pathogenic factors of delayed wound healing in DFU. Hypoxia-inducible factor-1 (HIF-1, a heterodimer of HIF-1α and HIF-1β) is a master regulator of oxygen homeostasis that mediates the adaptive cellular responses to hypoxia by regulating the expression of genes involved in angiogenesis, metabolic changes, proliferation, migration, and cell survival. However, HIF-1 signalling is inhibited in diabetes as a result of hyperglycaemia-induced HIF-1α destabilization and functional repression. Increasing HIF-1α expression and activity using various approaches promotes angiogenesis, EPC recruitment, and granulation, thereby improving wound healing in experimental diabetes. The mechanisms underlying HIF-1α regulation in diabetes and the therapeutic strategies targeting HIF-1 signalling for the treatment of diabetic wounds are discussed in this review. Further investigations of the pathways involved in HIF-1α regulation in diabetes are required to advance our understanding of the mechanisms underlying impaired wound healing in diabetes and to provide a foundation for developing novel therapeutic approaches to treat DFU.

  15. The G. L. Brown Prize Lecture. Hypoxic regulation of ion channel function and expression.

    Science.gov (United States)

    Peers, Chris

    2002-07-01

    Acute hypoxia regulates the activity of specific ion channels in a rapid and reversible manner. Such effects underlie appropriate cellular responses to hypoxia which are designed to initiate cardiorespiratory reflexes and contribute importantly to other tissue responses, all of which are designed to improve tissue O2 supply. These responses include excitation of chemoreceptors as well as pulmonary vasoconstriction and systemic vasodilatation. However, such responses may also contribute to the adverse responses to hypoxia, such as excitotoxicity in the central nervous system. Whilst numerous ion channel types are known to be modulated by acute hypoxia, the nature of the O2 sensor in most tissues remains to be identified. Prolonged (chronic) hypoxia regulates functional expression of ion channels, and so remodels excitability of various cell types. Whilst this may contribute to adaptive responses such as high-altitude acclimatization, such altered channel expression may also contribute to the onset of pathological disorders, including Alzheimer's disease. Indeed, evidence is emerging that production of pathological peptides associated with Alzheimer's disease is increased during prolonged hypoxia. Such effects may account for the known increased incidence of this disease in patients who have previously endured hypoxic episodes, such as congestive heart failure and stroke. Identification of the mechanisms coupling hypoxia to the increased production of these peptides is likely to be of therapeutic benefit.

  16. Studies on cerebral protection of digoxin against hypoxic-ischemic brain damage in neonatal rats.

    Science.gov (United States)

    Peng, Kaiwei; Tan, Danfeng; He, Miao; Guo, Dandan; Huang, Juan; Wang, Xia; Liu, Chentao; Zheng, Xiangrong

    2016-08-17

    Hypoxic-ischemic brain damage (HIBD) is a major cause of neonatal acute deaths and chronic nervous system damage. Our present study was designed to investigate the possible neuroprotective effect of digoxin-induced pharmacological preconditioning after hypoxia-ischemia and underlying mechanisms. Neonatal rats were assigned randomly to control, HIBD, or HIBD+digoxin groups. Pharmacological preconditioning was induced by administration of digoxin 72 h before inducing HIBD by carotid occlusion+hypoxia. Behavioral assays, and neuropathological and apoptotic assessments were performed to examine the effects; the expression of Na/K ATPase was also assessed. Rats in the HIBD group showed deficiencies on the T-maze, radial water maze, and postural reflex tests, whereas the HIBD+digoxin group showed significant improvements on all behavioral tests. The rats treated with digoxin showed recovery of pathological conditions, increased number of neural cells and proliferative cells, and decreased number of apoptotic cells. Meanwhile, an increased expression level of Na/K ATPase was observed after digoxin preconditioning treatment. The preconditioning treatment of digoxin contributed toward an improved functional recovery and exerted a marked neuroprotective effect including promotion of cell proliferation and reduction of apoptosis after HIBD, and the neuroprotective action was likely associated with increased expression of Na/K ATPase. PMID:27362436

  17. The City Mouse and the Country Mouse

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Once two mice (老鼠) were good friends. One lived in the city, the other lived in the country (乡村). After many years, the city mouse came to see the country mouse. The country mouse took him to his house in a field. He gave him the nicest food that he could find. The city mouse said,

  18. Overcoming Hypoxic-Resistance of Tumor Cells to TRAIL-Induced Apoptosis through Melatonin

    Directory of Open Access Journals (Sweden)

    You-Jin Lee

    2014-07-01

    Full Text Available A solid tumor is often exposed to hypoxic or anoxic conditions; thus, tumor cell responses to hypoxia are important for tumor progression as well as tumor therapy. Our previous studies indicated that tumor cells are resistant to tumor necrosis factor-related apoptosis-inducing ligand (TRAIL-induced cell apoptosis under hypoxic conditions. Melatonin inhibits cell proliferation in many cancer types and induces apoptosis in some particular cancer types. Here, we examined the effects of melatonin on hypoxic resistant cells against TRAIL-induced apoptosis and the possible mechanisms of melatonin in the hypoxic response. Melatonin treatment increased TRAIL-induced A549 cell death under hypoxic conditions, although hypoxia inhibited TRAIL-mediated cell apoptosis. In a mechanistic study, hypoxia inducible factor-1α and prolyl-hydroxylase 2 proteins, which increase following exposure to hypoxia, were dose-dependently down-regulated by melatonin treatment. Melatonin also blocked the hypoxic responses that reduced pro-apoptotic proteins and increased anti-apoptotic proteins including Bcl-2 and Bcl-xL. Furthermore, melatonin treatment reduced TRAIL resistance by regulating the mitochondrial transmembrane potential and Bax translocation. Our results first demonstrated that melatonin treatment induces apoptosis in TRAIL-resistant hypoxic tumor cells by diminishing the anti-apoptotic signals mediated by hypoxia and also suggest that melatonin could be a tumor therapeutic tool by combining with other apoptotic ligands including TRAIL, particularly in solid tumor cells exposed to hypoxia.

  19. A scenario and forecast model for Gulf of Mexico hypoxic area and volume

    Science.gov (United States)

    Scavia, Donald; Evans, Mary Anne; Obenour, Daniel R.

    2013-01-01

    For almost three decades, the relative size of the hypoxic region on the Louisiana-Texas continental shelf has drawn scientific and policy attention. During that time, both simple and complex models have been used to explore hypoxia dynamics and to provide management guidance relating the size of the hypoxic zone to key drivers. Throughout much of that development, analyses had to accommodate an apparent change in hypoxic sensitivity to loads and often cull observations due to anomalous meteorological conditions. Here, we describe an adaptation of our earlier, simple biophysical model, calibrated to revised hypoxic area estimates and new hypoxic volume estimates through Bayesian estimation. This application eliminates the need to cull observations and provides revised hypoxic extent estimates with uncertainties, corresponding to different nutrient loading reduction scenarios. We compare guidance from this model application, suggesting an approximately 62% nutrient loading reduction is required to reduce Gulf hypoxia to the Action Plan goal of 5,000 km2, to that of previous applications. In addition, we describe for the first time, the corresponding response of hypoxic volume. We also analyze model results to test for increasing system sensitivity to hypoxia formation, but find no strong evidence of such change.

  20. Diffusion-weighted MRI and proton MR spectroscopy in adult hypoxic brain injury

    International Nuclear Information System (INIS)

    Full text: The clinical and imaging assessment of patients with severe hypoxic brain injury is difficult, especially in the first few days after the insult. Proton spectroscopy has shown promise in the assessment of neonatal hypoxic brain injury, but there has been little experience with it in adults with such injury. The high sensitivity of diffusion-weighted imaging (DWI) for early stroke suggests that it may be more sensitive to hypoxic injury than conventional sequences. Patients with documented acute hypoxic episodes (cardiac arrest, hanging, measured severe arterial hypotension) and clinical evidence of hypoxic brain injury were included. MRI was not performed until sedation had been ceased for at least 24 hours. In addition to conventional T2-weighted and FLAIR imaging, six patients underwent DWI. A further ten patients underwent conventional imaging plus DWI and proton spectroscopy (PRESS TE 135, 2 x 2 x 2 cm voxel in parasagittal occipital cortex antero-inferiorly). Three of these patients were examined twice because of ongoing radiological and clinical uncertainty. In acute hypoxic insults, a negative diffusion-weighted study does not exclude significant brain injury. Proton spectroscopy is more sensitive to hypoxic brain injury, at least from 48 hours post-ictus, and may provide an index of severity. The findings suggest that acute hypoxia can trigger ongoing neuronal loss (over at least a week) without evidence of macroscopic infarction. Copyright (2002) Blackwell Science Pty Ltd

  1. Development of an ultrasound sensitive oxygen carrier for oxygen delivery to hypoxic tissue.

    Science.gov (United States)

    Eisenbrey, John R; Albala, Lorenzo; Kramer, Michael R; Daroshefski, Nick; Brown, David; Liu, Ji-Bin; Stanczak, Maria; O'Kane, Patrick; Forsberg, Flemming; Wheatley, Margaret A

    2015-01-15

    Radiation therapy is frequently used in the treatment of malignancies, but tumors are often more resistant than the surrounding normal tissue to radiation effects, because the tumor microenvironment is hypoxic. This manuscript details the fabrication and characterization of an ultrasound-sensitive, injectable oxygen microbubble platform (SE61O2) for overcoming tumor hypoxia. SE61O2 was fabricated by first sonicating a mixture of Span 60 and water-soluble vitamin E purged with perfluorocarbon gas. SE61O2 microbubbles were separated from the foam by flotation, then freeze dried under vacuum to remove all perfluorocarbon, and reconstituted with oxygen. Visually, SE61O2 microbubbles were smooth, spherical, with an average diameter of 3.1 μm and were reconstituted to a concentration of 6.5 E7 microbubbles/ml. Oxygen-filled SE61O2 provides 16.9 ± 1.0 dB of enhancement at a dose of 880 μl/l (5.7 E7 microbubbles/l) with a half-life under insonation of approximately 15 min. In in vitro release experiments, 2 ml of SE61O2 (1.3 E8 microbubbles) triggered with ultrasound was found to elevate oxygen partial pressures of 100ml of degassed saline 13.8 mmHg more than untriggered bubbles and 20.6 mmHg more than ultrasound triggered nitrogen-filled bubbles. In preliminary in vivo delivery experiments, triggered SE61O2 resulted in a 30.4 mmHg and 27.4 mmHg increase in oxygen partial pressures in two breast tumor mouse xenografts. PMID:25448552

  2. Oxygen supply maps for hypoxic microenvironment visualization in prostate cancer

    Science.gov (United States)

    Rupp, Niels J.; Schüffler, Peter J.; Zhong, Qing; Falkner, Florian; Rechsteiner, Markus; Rüschoff, Jan H.; Fankhauser, Christian; Drach, Matthias; Largo, Remo; Tremp, Mathias; Poyet, Cedric; Sulser, Tullio; Kristiansen, Glen; Moch, Holger; Buhmann, Joachim; Müntener, Michael; Wild, Peter J.

    2016-01-01

    Background: Intratumoral hypoxia plays an important role with regard to tumor biology and susceptibility to radio- and chemotherapy. For further investigation of hypoxia-related changes, areas of certain hypoxia must be reliably detected within cancer tissues. Pimonidazole, a 2-nitroimindazole, accumulates in hypoxic tissue and can be easily visualized using immunohistochemistry. Materials and Methods: To improve detection of highly hypoxic versus normoxic areas in prostate cancer, immunoreactivity of pimonidazole and a combination of known hypoxia-related proteins was used to create computational oxygen supply maps of prostate cancer. Pimonidazole was intravenously administered before radical prostatectomy in n = 15 patients, using the da Vinci robot-assisted surgical system. Prostatectomy specimens were immediately transferred into buffered formaldehyde, fixed overnight, and completely embedded in paraffin. Pimonidazole accumulation and hypoxia-related protein expression were visualized by immunohistochemistry. Oxygen supply maps were created using the normalized information from pimonidazole and hypoxia-related proteins. Results: Based on pimonidazole staining and other hypoxia.related proteins (osteopontin, hypoxia-inducible factor 1-alpha, and glucose transporter member 1) oxygen supply maps in prostate cancer were created. Overall, oxygen supply maps consisting of information from all hypoxia-related proteins showed high correlation and mutual information to the golden standard of pimonidazole. Here, we describe an improved computer-based ex vivo model for an accurate detection of oxygen supply in human prostate cancer tissue. Conclusions: This platform can be used for precise colocalization of novel candidate hypoxia-related proteins in a representative number of prostate cancer cases, and improve issues of single marker correlations. Furthermore, this study provides a source for further in situ tests and biochemical investigations PMID:26955501

  3. Involvement of SIRT1 in hypoxic down-regulation of c-Myc and β-catenin and hypoxic preconditioning effect of polyphenols

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Kyung-Soo [Department of Biochemistry, Pusan National University School of Medicine, Yangsan (Korea, Republic of); Research Center for Ischemic Tissue regeneration, Pusan National University School of Medicine, Yangsan (Korea, Republic of); Park, Jun-Ik [Department of Biochemistry, Pusan National University School of Medicine, Yangsan (Korea, Republic of); Kim, Mi-Ju; Kim, Hak-Bong; Lee, Jae-Won [Department of Biochemistry, Pusan National University School of Medicine, Yangsan (Korea, Republic of); Research Center for Ischemic Tissue regeneration, Pusan National University School of Medicine, Yangsan (Korea, Republic of); Dao, Trong Tuan; Oh, Won Keun [BK21 Project Team, College of Pharmacy, Chosun University, Gwangju (Korea, Republic of); Kang, Chi-Dug, E-mail: kcdshbw@pusan.ac.kr [Department of Biochemistry, Pusan National University School of Medicine, Yangsan (Korea, Republic of); Kim, Sun-Hee, E-mail: ksh7738@pusan.ac.kr [Department of Biochemistry, Pusan National University School of Medicine, Yangsan (Korea, Republic of); Research Center for Ischemic Tissue regeneration, Pusan National University School of Medicine, Yangsan (Korea, Republic of)

    2012-03-01

    SIRT1 has been found to function as a Class III deacetylase that affects the acetylation status of histones and other important cellular nonhistone proteins involved in various cellular pathways including stress responses and apoptosis. In this study, we investigated the role of SIRT1 signaling in the hypoxic down-regulations of c-Myc and β-catenin and hypoxic preconditioning effect of the red wine polyphenols such as piceatannol, myricetin, quercetin and resveratrol. We found that the expression of SIRT1 was significantly increased in hypoxia-exposed or hypoxic preconditioned HepG2 cells, which was closely associated with the up-regulation of HIF-1α and down-regulation of c-Myc and β-catenin expression via deacetylation of these proteins. In addition, blockade of SIRT1 activation using siRNA or amurensin G, a new potent SIRT1 inhibitor, abolished hypoxia-induced HIF-1α expression but increased c-Myc and β-catenin expression. SIRT1 was also found to stabilize HIF-1α protein and destabilize c-Myc, β-catenin and PHD2 under hypoxia. We also found that myricetin, quercetin, piceatannol and resveratrol up-regulated HIF-1α and down-regulated c-Myc, PHD2 and β-catenin expressions via SIRT1 activation, in a manner that mimics hypoxic preconditioning. This study provides new insights of the molecular mechanisms of hypoxic preconditioning and suggests that polyphenolic SIRT1 activators could be used to mimic hypoxic/ischemic preconditioning. -- Graphical abstract: Polyphenols mimicked hypoxic preconditioning by up-regulating HIF-1α and SIRT1 and down-regulating c-Myc, PHD2, and β-catenin. HepG2 cells were pretreated with the indicated doses of myricetin (MYR; A), quercetin (QUR; B), or piceatannol (PIC; C) for 4 h and then exposed to hypoxia for 4 h. Levels of HIF-1α, SIRT1, c-Myc, β-catenin, and PHD2 were determined by western blot analysis. The data are representative of three individual experiments. Highlights: ► SIRT1 expression is increased in hypoxia

  4. Involvement of SIRT1 in hypoxic down-regulation of c-Myc and β-catenin and hypoxic preconditioning effect of polyphenols

    International Nuclear Information System (INIS)

    SIRT1 has been found to function as a Class III deacetylase that affects the acetylation status of histones and other important cellular nonhistone proteins involved in various cellular pathways including stress responses and apoptosis. In this study, we investigated the role of SIRT1 signaling in the hypoxic down-regulations of c-Myc and β-catenin and hypoxic preconditioning effect of the red wine polyphenols such as piceatannol, myricetin, quercetin and resveratrol. We found that the expression of SIRT1 was significantly increased in hypoxia-exposed or hypoxic preconditioned HepG2 cells, which was closely associated with the up-regulation of HIF-1α and down-regulation of c-Myc and β-catenin expression via deacetylation of these proteins. In addition, blockade of SIRT1 activation using siRNA or amurensin G, a new potent SIRT1 inhibitor, abolished hypoxia-induced HIF-1α expression but increased c-Myc and β-catenin expression. SIRT1 was also found to stabilize HIF-1α protein and destabilize c-Myc, β-catenin and PHD2 under hypoxia. We also found that myricetin, quercetin, piceatannol and resveratrol up-regulated HIF-1α and down-regulated c-Myc, PHD2 and β-catenin expressions via SIRT1 activation, in a manner that mimics hypoxic preconditioning. This study provides new insights of the molecular mechanisms of hypoxic preconditioning and suggests that polyphenolic SIRT1 activators could be used to mimic hypoxic/ischemic preconditioning. -- Graphical abstract: Polyphenols mimicked hypoxic preconditioning by up-regulating HIF-1α and SIRT1 and down-regulating c-Myc, PHD2, and β-catenin. HepG2 cells were pretreated with the indicated doses of myricetin (MYR; A), quercetin (QUR; B), or piceatannol (PIC; C) for 4 h and then exposed to hypoxia for 4 h. Levels of HIF-1α, SIRT1, c-Myc, β-catenin, and PHD2 were determined by western blot analysis. The data are representative of three individual experiments. Highlights: ► SIRT1 expression is increased in hypoxia

  5. Renal compensation to chronic hypoxic hypercapnia: downregulation of pendrin and adaptation of the proximal tubule

    DEFF Research Database (Denmark)

    de Seigneux, Sophie; Malte, Hans; Dimke, Henrik;

    2007-01-01

    hypercapnia and hypoxia [8% CO(2) and 13% O(2) (hypercapnic, n = 6) or normal air (controls, n = 6)] in an environmental chamber for 10 days and were killed under the same atmosphere. In hypercapnic rats, arterial pH was lower than controls (7.31 +/- 0.01 vs. 7.39 +/- 0.01, P = 0.03), blood HCO(3...

  6. A Qualitative Study of Physician Perspectives on Prognostication in Neonatal Hypoxic Ischemic Encephalopathy.

    Science.gov (United States)

    Rasmussen, Lisa Anne; Bell, Emily; Racine, Eric

    2016-10-01

    Hypoxic ischemic encephalopathy is the most frequent cause of neonatal encephalopathy and yields a great degree of morbidity and mortality. From an ethical and clinical standpoint, neurological prognosis is fundamental in the care of neonates with hypoxic ischemic encephalopathy. This qualitative study explores physician perspectives about neurological prognosis in neonatal hypoxic ischemic encephalopathy. This study aimed, through semistructured interviews with neonatologists and pediatric neurologists, to understand the practice of prognostication. Qualitative thematic content analysis was used for data analysis. The authors report 2 main findings: (1) neurological prognosis remains fundamental to quality-of-life predictions and considerations of best interest, and (2) magnetic resonance imaging is presented to parents with a greater degree of certainty than actually exists. Further research is needed to explore both the parental perspective and, prospectively, the impact of different clinical approaches and styles to prognostication for neonatal hypoxic ischemic encephalopathy.

  7. Sex-dependent regulation of hypoxic ventilation in mice and humans is mediated by erythropoietin

    DEFF Research Database (Denmark)

    Soliz, Jorge; Thomsen, Jonas Juhl; Soulage, Christophe;

    2009-01-01

    Acclimatization to hypoxic exposure relies on an elevated ventilation and erythropoietic activity. We recently proposed that erythropoietin (Epo) links both responses: apart from red blood cell production, cerebral and plasma Epo interact with the central and peripheral respiratory centers. Knowing...

  8. Use of perampanel in one case of super-refractory hypoxic myoclonic status: Case report

    Directory of Open Access Journals (Sweden)

    Estevo Santamarina

    2015-01-01

    Conclusion: This case shows the potential utility of PER as a therapeutic option in super-refractory hypoxic status and even its potential use before other aggressive alternatives considering their greater morbidity.

  9. Hypoxic training for swimmer's combined team preparation of the law university

    Directory of Open Access Journals (Sweden)

    Balamutova N.M.

    2012-03-01

    Full Text Available The matters of the hypoxic training for highly qualified swimmers as extra means of improving level for sports achievements were considered. A method of artificial hypoxic training that increase indexes of cardiorespiratory system of tested people was developed. Twelve students from the university swimming combined team took part in the experiment. In the experiment were used pedagogical testing methods, biochemistry analysis of blood, cardiorespiratory indexes rating, methods of mathematical statistics. It was determined that offered methodology of hypoxic training allows to reach higher sports achievements. It is set that the use of irregular hypoxic influences is considerably modified dependence a «dose is an effect» in regard to loadings of anaerobic alactic influence

  10. Hypoxic fraction determinations with the BA1112 rat sarcoma: variation within and among assay techniques

    International Nuclear Information System (INIS)

    Measurement of the hypoxic fraction in the same tumor system by different assay techniques often gives incompatible results. The hypoxic fraction of the BA1112 sarcoma has been measured by three assay techniques: tumor control and growth delay assays in which the tumors remain in situ after irradiation, and paired survival curve assays in which the tumors are excised after irradiation. The assays were done with and without anesthesia on tumors growing in two different subcutaneous sites. Interpretation of the results was complicated by disagreements between the growth delay and tumor control assays, and by disparities between replicate determinations. The discrepancies among assays are caused almost entirely by variations in the response of the artifically hypoxic tumors, rather than variations in the response of aerobic tumors. These results indicate that assumptions commonly made when measuring hypoxic fractions may not be valid

  11. Intramucosal–arterial PCO 2 gap fails to reflect intestinal dysoxia in hypoxic hypoxia

    OpenAIRE

    Dubin, Arnaldo; Murias, Gastón; Estenssoro, Elisa; Canales, Héctor; Badie, Julio; Pozo, Mario; Sottile, Juan P; Barán, Marcelo; Pálizas, Fernando; Laporte, Mercedes

    2002-01-01

    Introduction An elevation in intramucosal–arterial PCO 2 gradient (ΔPCO 2) could be determined either by tissue hypoxia or by reduced blood flow. Our hypothesis was that in hypoxic hypoxia with preserved blood flow, ΔPCO 2 should not be altered. Methods In 17 anesthetized and mechanically ventilated sheep, oxygen delivery was reduced by decreasing flow (ischemic hypoxia, IH) or arterial oxygen saturation (hypoxic hypoxia, HH), or no intervention was made (sham). In the IH group (n = 6), blood...

  12. Environmental enrichment promotes neural remodeling in newborn rats with hypoxic-ischemic brain damage

    Institute of Scientific and Technical Information of China (English)

    Chuanjun Liu; Yankui Guo; Yalu Li; Zhenying Yang

    2011-01-01

    We evaluated the effect of hypoxic-ischemic brain damage and treatment with early environmental enrichment intervention on development of newborn rats, as evaluated by light and electron microscopy and morphometry. Early intervention with environmental enrichment intelligence training attenuated brain edema and neuronal injury, promoted neuronal repair, and increased neuronal plasticity in the frontal lobe cortex of the newborn rats with hypoxic-ischemic brain damage.

  13. Hypoxic Epithelial Necrosis Triggers Neutrophilic Inflammation via IL-1 Receptor Signaling in Cystic Fibrosis Lung Disease

    OpenAIRE

    Fritzsching, Benedikt; Zhou-Suckow, Zhe; Trojanek, Joanna B.; Schubert, Susanne C.; Schatterny, Jolanthe; Hirtz, Stephanie; Agrawal, Raman; Muley, Thomas; Kahn, Nicolas; Sticht, Carsten; Gunkel, Nikolas; Welte, Tobias; Scott H Randell; Länger, Florian; Schnabel, Philipp

    2015-01-01

    Rationale: In many organs, hypoxic cell death triggers sterile neutrophilic inflammation via IL-1R signaling. Although hypoxia is common in airways from patients with cystic fibrosis (CF), its role in neutrophilic inflammation remains unknown. We recently demonstrated that hypoxic epithelial necrosis caused by airway mucus obstruction precedes neutrophilic inflammation in Scnn1b-transgenic (Scnn1b-Tg) mice with CF-like lung disease.

  14. Screening and identification of a specific peptide for targeting hypoxic hepatoma cells.

    Science.gov (United States)

    Liu, Yiming; Xia, Xiangwen; Wang, Yong; Li, Xin; Zhou, Guofeng; Liang, Huiming; Feng, Gansheng; Zheng, Chuansheng

    2016-08-01

    The biological behaviors of residual hepatoma cells after transarterial embolization therapy, which exist in a hypoxic or even anaerobic tumor microenvironment, differ from the tumor cells under normoxic conditions. This study aimed to use a phage display peptide library for in vivo and in vitro screening to obtain a peptide which could specifically bind to hypoxic hepatoma cells, allowing further targeted diagnosis and treatment for liver cancer. In this study, hypoxic hepatoma cells HepG2 (targeted cells), and normal liver cells HL-7702 (control cells), were utilized to perform three rounds of in vitro screening using a phage-displayed 7-mer peptide library. In addition, hypoxic HepG2 were subcutaneously injected into nude mice to establish a hepatocarcinoma model, followed by performing three rounds of in vivo screening on the phages identified from the in vitro screening. The products from the screening were further identified using ELISA and immunofluorescence staining on cells and tissues. The results indicated that the P11 positive clone had the highest binding effect with hypoxic hepatoma cells. The sequence of the exogenous insert fragment of P11 positive clone was obtained by sequencing: GSTSFSK. The binding assay indicated that GSTSFSK could specifically bind to hypoxic hepatoma cells and hepatocarcinoma tissues. This 7-mer peptide has the potential to be developed as an useful molecular to the targeting diagnosis and treatment of residual hepatoma cells after transarterial chemoembolization. PMID:27381416

  15. Quantification of structural changes in the corpus callosumin children with profound hypoxic-ischaemic brain injury

    International Nuclear Information System (INIS)

    Birth-related acute profound hypoxic-ischaemic brain injury has specific patterns of damage including the paracentral lobules. To test the hypothesis that there is anatomically coherent regional volume loss of the corpus callosum as a result of this hemispheric abnormality. Study subjects included 13 children with proven acute profound hypoxic-ischaemic brain injury and 13 children with developmental delay but no brain abnormalities. A computerised system divided the corpus callosum into 100 segments, measuring each width. Principal component analysis grouped the widths into contiguous anatomical regions. We conducted analysis of variance of corpus callosum widths as well as support vector machine stratification into patient groups. There was statistically significant narrowing of the mid-posterior body and genu of the corpus callosum in children with hypoxic-ischaemic brain injury. Support vector machine analysis yielded over 95% accuracy in patient group stratification using the corpus callosum centile widths. Focal volume loss is seen in the corpus callosum of children with hypoxic-ischaemic brain injury secondary to loss of commissural fibres arising in the paracentral lobules. Support vector machine stratification into the hypoxic-ischaemic brain injury group or the control group on the basis of corpus callosum width is highly accurate and points towards rapid clinical translation of this technique as a potential biomarker of hypoxic-ischaemic brain injury. (orig.)

  16. Nitric oxide modulates hypoxic pulmonary smooth muscle cell proliferation and apoptosis by regulating carbon monoxide pathway

    Institute of Scientific and Technical Information of China (English)

    Yan-fei WANG; Hong TIAN; Chao-shu TANG; Hong-fang JIN; Jun-bao DU

    2007-01-01

    Aim: To explore the role of carbon monoxide (CO) in the regulation of hypoxic pulmonary artery smooth muscle cell (PASMC) proliferation and apoptosis by nitric oxide (NO). Methods: PASMC of Wistar rats was cultured in vitro in the presence of a NO donor, sodium nitroprusside, or an inhibitor of heme oxygenase (HO), zinc protoporphyrin-IX, or under both normoxic and hypoxic conditions.Nitrite and carboxyhemoglobin in PASMC medium were detected with spectrophotometry. The proliferating and apoptotic percentage of PASMC was measured by flow cytometry. The expression of HO-1 mRNA in PASMC was analyzed by fluorescent real-time quantitative PCR, and the proliferating cell nuclear antigen and caspase-3 were examined by immunocytochemical analysis. Results: The results showed that hypoxia suppressed NO generation from PASMC, which promoted hypoxic PASMC proliferation and induced apoptosis. Meanwhile, hy-poxia induced HO-1 expression in PASMC and promoted CO production from PASMC, which inhibited PASMC proliferation and regulated PASMC apoptosis. NO upregulated the expression of HO-1 mRNA in hypoxic PASMC; NO also inhib-ited proliferation and promoted apoptosis of hypoxic PASMC, possibly by regu-lating the production of CO. Conclusion: The results indicated that CO could inhibit proliferation and regulate apoptosis of PASMC, and NO inhibited prolifera-tion and promoted apoptosis of hypoxic PASMC, possibly by regulating the pro-duction of CO.

  17. Using the endocannabinoid system as a neuroprotective strategy in perinatal hypoxic- ischemic brain injury

    Institute of Scientific and Technical Information of China (English)

    Lara-Celador, I.; Go(n)i-de-Cerio, F.; Antonia Alvarez; Enrique Hilario

    2013-01-01

    One of the most important causes of brain injury in the neonatal period is a perinatal hypoxic- ischemic event. This devastating condition can lead to long-term neurological deficits or even death. After hypoxic-ischemic brain injury, a variety of specific cellular mechanisms are set in motion, triggering cell damage and finally producing cell death. Effective therapeutic treatments against this phenomenon are still unavailable because of complex molecular mechanisms underlying hypoxic-ischemic brain injury. After a thorough understanding of the mechanism underlying neural plasticity following hypoxic-ischemic brain injury, various neuroprotective therapies have been developed for alleviating brain injury and improving long-term outcomes. Among them, the endocannabinoid system emerges as a natural system of neuroprotection. The endocannabinoid system modulates a wide range of physiological processes in mammals and has demonstrated neuroprotective effects in different paradigms of acute brain injury, acting as a natural neuroprotectant. The aim of this review is to study the use of different therapies to induce long-term therapeutic effects after hypoxic-ischemic brain injury, and analyze the important role of the endocannabinoid system as a new neuroprotective strategy against perinatal hypoxic-ischemic brain injury.

  18. Sickle erythrocytes target cytotoxics to hypoxic tumor microvessels and potentiate a tumoricidal response.

    Directory of Open Access Journals (Sweden)

    David S Terman

    Full Text Available Resistance of hypoxic solid tumor niches to chemotherapy and radiotherapy remains a major scientific challenge that calls for conceptually new approaches. Here we exploit a hitherto unrecognized ability of sickled erythrocytes (SSRBCs but not normal RBCs (NLRBCs to selectively target hypoxic tumor vascular microenviroment and induce diffuse vaso-occlusion. Within minutes after injection SSRBCs, but not NLRBCs, home and adhere to hypoxic 4T1 tumor vasculature with hemoglobin saturation levels at or below 10% that are distributed over 70% of the tumor space. The bound SSRBCs thereupon form microaggregates that obstruct/occlude up to 88% of tumor microvessels. Importantly, SSRBCs, but not normal RBCs, combined with exogenous prooxidant zinc protoporphyrin (ZnPP induce a potent tumoricidal response via a mutual potentiating mechanism. In a clonogenic tumor cell survival assay, SSRBC surrogate hemin, along with H(2O(2 and ZnPP demonstrate a similar mutual potentiation and tumoricidal effect. In contrast to existing treatments directed only to the hypoxic tumor cell, the present approach targets the hypoxic tumor vascular environment and induces injury to both tumor microvessels and tumor cells using intrinsic SSRBC-derived oxidants and locally generated ROS. Thus, the SSRBC appears to be a potent new tool for treatment of hypoxic solid tumors, which are notable for their resistance to existing cancer treatments.

  19. HIF-1α siRNA Leads to Apoptosis of Pancreatic Cancer Cells under Hypoxic Conditions

    Institute of Scientific and Technical Information of China (English)

    Chuangui Chen; Jianqiu Chen; Jinjin Sun

    2009-01-01

    OBJECTIVE To explore the role of hypoxic inducible factor-1α(HIF-1α) in the proliferation and apoptosis of pancreatic cancer cells under hypoxic conditions.METHODS A cassette encoding small interference RNA (siRNA)targeting HIF-1α mediated by recombinant adeno-associated virus (rAAV) was constructed, giving rAAV-siHIF, rAAV-siHIF or rAAV- hrGFP was transfected into exponentially growing MiaPaCa2 cells under hypoxic conditions. Then, the expression of HIF-1αmRNA and protein, the proliferation and apoptosis of MiaPaCa2 cells were examined, using real-time PCR, Western Blot, MTT and TUNEL, respectively.RESULTS Under hypoxic conditions, rAAV-siHIF inhibited the expression of HIF-1α mRNA and protein in MiaPaCa2 cells. At the same time, rAAV-siHIF decreased MiaPaCa2 cell proliferation and induced apoptosis. However, rAAV-hrGFP had no effect on the expression of HIF-1α as well as the proliferation and apoptosis of MiaPaCa2 cells under hypoxic conditions.CONCLUSION Under hypoxic conditions, HIF-1α plays a key role in the proliferation of MiaPaCa2 cells, and inhibition of HIF-1α expression can lead to MiaPaCa2 cell apoptosis.

  20. Interaction between endogenous nitric oxide and carbon monoxide in the pathogenesis of hypoxic pulmonary hypertension

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    The aim of the study was to investigate the interaction between nitric oxygenase (NOS)/ nitric oxide (NO) and heme oxygenase (HO)/ carbon monoxide (CO) system in the pathogenesis of hypoxic pulmonary hypertension. On a rat model of hypoxic pulmonary hypertension, the pulmonary artery pressure was measured, and NO formation and expression of NOS in pulmonary tissues were examined after treatment with ZnPP-IX, an HO-1 inhibitor. The pulmonary artery pressure, CO formation and expression of HO-1 in pulmonary tissues were examined after treatment with L-NAME, a NOS inhibitor. We found that pulmonary hypertension developed after 2-week hypoxia, while the concentration of NO in the pulmonary tissue homogenates and the expression of NOS in intrapulmonary artery endothelial cells decreased markedly. ZnPP-IX worsened pulmonary hypertension of hypoxic rats. However, it increased endogenous production of NO and the expression of NOS obviously. The concentration of CO in the pulmonary tissue homogenates and the expression of HO-1 in intrapulmonary artery smooth muscle cells increased markedly with hypoxic pulmonary hypertension. L-NAME worsened pulmonary hypertension of hypoxic rats, but inhibited CO formation and HO-1 expression (P < 0.01). The results of this study suggested that endogenous NOS/NO and HO/CO systems might interact with each other and therefore play an important regulating role in hypoxic pulmonary hypertension.

  1. Archaeal enrichment in the hypoxic zone in the northern Gulf of Mexico.

    Science.gov (United States)

    Gillies, Lauren E; Thrash, J Cameron; deRada, Sergio; Rabalais, Nancy N; Mason, Olivia U

    2015-10-01

    Areas of low oxygen have spread exponentially over the past 40 years, and are cited as a key stressor on coastal ecosystems. The world's second largest coastal hypoxic (≤ 2 mg of O2 l(-1)) zone occurs annually in the northern Gulf of Mexico. The net effect of hypoxia is the diversion of energy flow away from higher trophic levels to microorganisms. This energy shunt is consequential to the overall productivity of hypoxic water masses and the ecosystem as a whole. In this study, water column samples were collected at 39 sites in the nGOM, 21 of which were hypoxic. Analysis of the microbial community along a hypoxic to oxic dissolved oxygen gradient revealed that the relative abundance (iTag) of Thaumarchaeota species 16S rRNA genes (> 40% of the microbial community in some hypoxic samples), the absolute abundance (quantitative polymerase chain reaction; qPCR) of Thaumarchaeota 16S rRNA genes and archaeal ammonia-monooxygenase gene copy number (qPCR) were significantly higher in hypoxic samples. Spatial interpolation of the microbial and chemical data revealed a continuous, shelfwide band of low dissolved oxygen waters that were dominated by Thaumarchaeota (and Euryarchaeota), amoA genes and high concentrations of phosphate in the nGOM, thus implicating physicochemical forcing on microbial abundance. PMID:25818237

  2. Tumorigenicity of hypoxic respiring cancer cells revealed by a hypoxia–cell cycle dual reporter

    Science.gov (United States)

    Le, Anne; Stine, Zachary E.; Nguyen, Christopher; Afzal, Junaid; Sun, Peng; Hamaker, Max; Siegel, Nicholas M.; Gouw, Arvin M.; Kang, Byung-hak; Yu, Shu-Han; Cochran, Rory L.; Sailor, Kurt A.; Song, Hongjun; Dang, Chi V.

    2014-01-01

    Although aerobic glycolysis provides an advantage in the hypoxic tumor microenvironment, some cancer cells can also respire via oxidative phosphorylation. These respiring (“non-Warburg”) cells were previously thought not to play a key role in tumorigenesis and thus fell from favor in the literature. We sought to determine whether subpopulations of hypoxic cancer cells have different metabolic phenotypes and gene-expression profiles that could influence tumorigenicity and therapeutic response, and we therefore developed a dual fluorescent protein reporter, HypoxCR, that detects hypoxic [hypoxia-inducible factor (HIF) active] and/or cycling cells. Using HEK293T cells as a model, we identified four distinct hypoxic cell populations by flow cytometry. The non-HIF/noncycling cell population expressed a unique set of genes involved in mitochondrial function. Relative to the other subpopulations, these hypoxic “non-Warburg” cells had highest oxygen consumption rates and mitochondrial capacity consistent with increased mitochondrial respiration. We found that these respiring cells were unexpectedly tumorigenic, suggesting that continued respiration under limiting oxygen conditions may be required for tumorigenicity. PMID:25114222

  3. Quantification of structural changes in the corpus callosumin children with profound hypoxic-ischaemic brain injury

    Energy Technology Data Exchange (ETDEWEB)

    Stivaros, Stavros M. [Manchester Academic Health Science Centre, Academic Unit of Paediatric Radiology, Royal Manchester Children' s Hospital, Central Manchester University Hospitals NHS Foundation Trust, Manchester (United Kingdom); University of Manchester, Centre for Imaging Sciences, Institute of Population Health, Manchester (United Kingdom); Radon, Mark R. [The Walton Centre NHS Foundation Trust, Department of Neuroradiology, Liverpool (United Kingdom); Mileva, Reneta; Gledson, Ann; Keane, John A. [University of Manchester, School of Computer Science, Manchester (United Kingdom); Connolly, Daniel J.A.; Batty, Ruth [Sheffield Children' s Hospital NHS Foundation Trust, Department of Neuroradiology, Sheffield (United Kingdom); Cowell, Patricia E. [University of Sheffield, Department of Human Communication Sciences, Sheffield (United Kingdom); Hoggard, Nigel; Griffiths, Paul D. [University of Sheffield, Academic Unit of Radiology, Sheffield (United Kingdom); Wright, Neville B.; Tang, Vivian [Manchester Academic Health Science Centre, Academic Unit of Paediatric Radiology, Royal Manchester Children' s Hospital, Central Manchester University Hospitals NHS Foundation Trust, Manchester (United Kingdom)

    2016-01-15

    Birth-related acute profound hypoxic-ischaemic brain injury has specific patterns of damage including the paracentral lobules. To test the hypothesis that there is anatomically coherent regional volume loss of the corpus callosum as a result of this hemispheric abnormality. Study subjects included 13 children with proven acute profound hypoxic-ischaemic brain injury and 13 children with developmental delay but no brain abnormalities. A computerised system divided the corpus callosum into 100 segments, measuring each width. Principal component analysis grouped the widths into contiguous anatomical regions. We conducted analysis of variance of corpus callosum widths as well as support vector machine stratification into patient groups. There was statistically significant narrowing of the mid-posterior body and genu of the corpus callosum in children with hypoxic-ischaemic brain injury. Support vector machine analysis yielded over 95% accuracy in patient group stratification using the corpus callosum centile widths. Focal volume loss is seen in the corpus callosum of children with hypoxic-ischaemic brain injury secondary to loss of commissural fibres arising in the paracentral lobules. Support vector machine stratification into the hypoxic-ischaemic brain injury group or the control group on the basis of corpus callosum width is highly accurate and points towards rapid clinical translation of this technique as a potential biomarker of hypoxic-ischaemic brain injury. (orig.)

  4. Ceftriaxone attenuates hypoxic-ischemic brain injury in neonatal rats

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    Huang Yen

    2011-09-01

    Full Text Available Abstract Background Perinatal brain injury is the leading cause of subsequent neurological disability in both term and preterm baby. Glutamate excitotoxicity is one of the major factors involved in perinatal hypoxic-ischemic encephalopathy (HIE. Glutamate transporter GLT1, expressed mainly in mature astrocytes, is the major glutamate transporter in the brain. HIE induced excessive glutamate release which is not reuptaked by immature astrocytes may induce neuronal damage. Compounds, such as ceftriaxone, that enhance the expression of GLT1 may exert neuroprotective effect in HIE. Methods We used a neonatal rat model of HIE by unilateral ligation of carotid artery and subsequent exposure to 8% oxygen for 2 hrs on postnatal day 7 (P7 rats. Neonatal rats were administered three dosages of an antibiotic, ceftriaxone, 48 hrs prior to experimental HIE. Neurobehavioral tests of treated rats were assessed. Brain sections from P14 rats were examined with Nissl and immunohistochemical stain, and TUNEL assay. GLT1 protein expression was evaluated by Western blot and immunohistochemistry. Results Pre-treatment with 200 mg/kg ceftriaxone significantly reduced the brain injury scores and apoptotic cells in the hippocampus, restored myelination in the external capsule of P14 rats, and improved the hypoxia-ischemia induced learning and memory deficit of P23-24 rats. GLT1 expression was observed in the cortical neurons of ceftriaxone treated rats. Conclusion These results suggest that pre-treatment of infants at risk for HIE with ceftriaxone may reduce subsequent brain injury.

  5. Concepts of hypoxic NO signaling in remote ischemic preconditioning

    Institute of Scientific and Technical Information of China (English)

    Matthias; Totzeck; Ulrike; Hendgen-Cotta; Tienush; Rassaf

    2015-01-01

    Acute coronary syndromes remain a leading single cause of death worldwide. Therapeutic strategies to treat cardiomyocyte threatening ischemia/reperfusion injury are urgently needed. Remote ischemic preconditioning(r IPC) applied by brief ischemic episodes to heartdistant organs has been tested in several clinical studies, and the major body of evidence points to beneficial effects of r IPC for patients. The underlying signaling, however, remains incompletely understood. This relates particularly to the mechanism by which the protective signal is transferred from the remote site to the target organ. Many pathways have been forwarded but none can explain the protective effects completely. In light of recent experimental studies, we here outline the current knowledge relating to the generation of the protective signal in the remote organ, the signal transfer to the target organ and the transduction of the transferred signal into cardioprotection. The majority of studies favors a humoral factor that activates cardiomyocyte downstream signaling- receptor-dependent and independently. Cellular targets include deleterious calcium(Ca2+) signaling, reactive oxygen species, mitochondrial function and structure, and cellular apoptosis and necrosis. Following an outline of the existing evidence, we will furthermore characterize the existing knowledge and discuss future perspectives with particular emphasis on the interaction between the recently discovered hypoxic nitrite-nitric oxide signaling in r IPC. This refers to the protective role of nitrite, which can be activated endogenously using r IPC and which then contributes to cardioprotection by rIPC.

  6. Neuroprotective Therapies after Perinatal Hypoxic-Ischemic Brain Injury

    Directory of Open Access Journals (Sweden)

    Enrique Hilario

    2013-03-01

    Full Text Available Hypoxic-ischemic (HI brain injury is one of the main causes of disabilities in term-born infants. It is the result of a deprivation of oxygen and glucose in the neural tissue. As one of the most important causes of brain damage in the newborn period, the neonatal HI event is a devastating condition that can lead to long-term neurological deficits or even death. The pattern of this injury occurs in two phases, the first one is a primary energy failure related to the HI event and the second phase is an energy failure that takes place some hours later. Injuries that occur in response to these events are often manifested as severe cognitive and motor disturbances over time. Due to difficulties regarding the early diagnosis and treatment of HI injury, there is an increasing need to find effective therapies as new opportunities for the reduction of brain damage and its long term effects. Some of these therapies are focused on prevention of the production of reactive oxygen species, anti-inflammatory effects, anti-apoptotic interventions and in a later stage, the stimulation of neurotrophic properties in the neonatal brain which could be targeted to promote neuronal and oligodendrocyte regeneration.

  7. Stem Cell Therapy for Neonatal Hypoxic-Ischemic Encephalopathy

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    Gabriel eGonzales-Portillo

    2014-08-01

    Full Text Available Treatments for neonatal hypoxic ischemic encephalopathy (HIE have been limited. The aim of this paper is to offer translational research guidance on stem cell therapy for neonatal HIE by examining clinically relevant animal models, practical stem cell sources, safety and efficacy of endpoint assays, as well as a general understanding of modes of action of this cellular therapy. In order to do so, we discuss the clinical manifestations of HIE, highlighting its overlapping pathologies with stroke providing insights on the potential of cell therapy, currently investigated in stroke, for HIE. To this end, we draw guidance from recommendations outlined in Stem cell Therapeutics as an Emerging Paradigm for Stroke or STEPS, which have been recently modified to Baby STEPS to cater for the neonatal symptoms of HIE. These guidelines recognized that neonatal HIE exhibits distinct disease symptoms from adult stroke in need of an innovative translational approach that facilitates the entry of cell therapy in the clinic. Finally, new information about recent clinical trials, and insights into combination therapy are provided with the vision that stem cell therapy may benefit from available treatments, such as hypothermia, already being tested in children diagnosed with HIE.

  8. Natural Compounds Regulate Glycolysis in Hypoxic Tumor Microenvironment

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    Jian-Li Gao

    2015-01-01

    Full Text Available In the early twentieth century, Otto Heinrich Warburg described an elevated rate of glycolysis occurring in cancer cells, even in the presence of atmospheric oxygen (the Warburg effect. Recently it became a therapeutically interesting strategy and is considered as an emerging hallmark of cancer. Hypoxia inducible factor-1 (HIF-1 is one of the key transcription factors that play major roles in tumor glycolysis and could directly trigger Warburg effect. Thus, how to inhibit HIF-1-depended Warburg effect to assist the cancer therapy is becoming a hot issue in cancer research. In fact, HIF-1 upregulates the glucose transporters (GLUT and induces the expression of glycolytic enzymes, such as hexokinase, pyruvate kinase, and lactate dehydrogenase. So small molecules of natural origin used as GLUT, hexokinase, or pyruvate kinase isoform M2 inhibitors could represent a major challenge in the field of cancer treatment. These compounds aim to suppress tumor hypoxia induced glycolysis process to suppress the cell energy metabolism or enhance the susceptibility of tumor cells to radio- and chemotherapy. In this review, we highlight the role of natural compounds in regulating tumor glycolysis, with a main focus on the glycolysis under hypoxic tumor microenvironment.

  9. Mouse Models of Rheumatoid Arthritis.

    Science.gov (United States)

    Caplazi, P; Baca, M; Barck, K; Carano, R A D; DeVoss, J; Lee, W P; Bolon, B; Diehl, L

    2015-09-01

    Rheumatoid arthritis (RA) is a chronic debilitating autoimmune disorder characterized by synovitis that leads to cartilage and bone erosion by invading fibrovascular tissue. Mouse models of RA recapitulate many features of the human disease. Despite the availability of medicines that are highly effective in many patient populations, autoimmune diseases (including RA) remain an area of active biomedical research, and consequently mouse models of RA are still extensively used for mechanistic studies and validation of therapeutic targets. This review aims to integrate morphologic features with model biology and cover the key characteristics of the most commonly used induced and spontaneous mouse models of RA. Induced models emphasized in this review include collagen-induced arthritis and antibody-induced arthritis. Collagen-induced arthritis is an example of an active immunization strategy, whereas antibody- induced arthritis models, such as collagen antibody-induced arthritis and K/BxN antibody transfer arthritis, represent examples of passive immunization strategies. The coverage of spontaneous models in this review is focused on the TNFΔ (ARE) mouse, in which arthritis results from overexpression of TNF-α, a master proinflammatory cytokine that drives disease in many patients.

  10. Mouse Models of Rheumatoid Arthritis.

    Science.gov (United States)

    Caplazi, P; Baca, M; Barck, K; Carano, R A D; DeVoss, J; Lee, W P; Bolon, B; Diehl, L

    2015-09-01

    Rheumatoid arthritis (RA) is a chronic debilitating autoimmune disorder characterized by synovitis that leads to cartilage and bone erosion by invading fibrovascular tissue. Mouse models of RA recapitulate many features of the human disease. Despite the availability of medicines that are highly effective in many patient populations, autoimmune diseases (including RA) remain an area of active biomedical research, and consequently mouse models of RA are still extensively used for mechanistic studies and validation of therapeutic targets. This review aims to integrate morphologic features with model biology and cover the key characteristics of the most commonly used induced and spontaneous mouse models of RA. Induced models emphasized in this review include collagen-induced arthritis and antibody-induced arthritis. Collagen-induced arthritis is an example of an active immunization strategy, whereas antibody- induced arthritis models, such as collagen antibody-induced arthritis and K/BxN antibody transfer arthritis, represent examples of passive immunization strategies. The coverage of spontaneous models in this review is focused on the TNFΔ (ARE) mouse, in which arthritis results from overexpression of TNF-α, a master proinflammatory cytokine that drives disease in many patients. PMID:26063174

  11. Influence of hyperbaric oxygen on the differentiation of hypoxic/ischemic brain-derived neural stem cells

    Institute of Scientific and Technical Information of China (English)

    Zhengrong Peng; Sue Wang; Pingtian Xiao

    2009-01-01

    BACKGROUND: It has been previously shown that hyperbaric oxygen may promote proliferation of neural stem cells and reduce death of endogenous neural stem cells (NSCs).OBJECTIVE: To explore the effects of hyperbaric oxygen on the differentiation of hypoxic/ischemic brain-derived NSCs into neuron-like cells and compare with high-concentration oxygen and high pressure.DESIGN, TIME AND SETTING: An in vitro contrast study, performed at Laboratory of Neurology,Central South University between January and May 2006.MATERIALS: A hyperbaric oxygen chamber (YLC 0.5/1A) was provided by Wuhan Shipping Design Research Institute; mouse anti-rat microtubute-associated protein 2 monoclonal antibody by Jingmei Company, Beijing; mouse anti-rat glial fibrillary acidic protein monoclonal antibody by Neo Markers,USA; mouse anti-rat galactocerebroside monoclonal antibody by Santa Cruz Biotechnology Inc.,USA; and goat anti-mouse fluorescein isothiocyanate-labeled secondary antibody by Wuhan Boster Bioengineering Co., Ltd., China.METHODS: Brain-derived NSCs isolated from brain tissues of neonatal Sprague Dawiey rats werecloned and passaged, and assigned into five groups: normal control, model, high-concentration oxygen, high pressure, and hyperbaric oxygen groups. Cells in the four groups, excluding the normal control group, were incubated in serum-containing DMEM/F12 culture medium. Hypoxic/ischemic models of NSCs were established in an incubator comprising 93% N2, 5% CO2, and 2% O2.Thereafter, cells were continuously cultured as follows: compressed air (0.2 MPa, 1 hour, once a day)in the high pressure group, compressed air+a minimum of 80% O2 in the hyperbaric oxygen group,and a minimum of 80% O2 in the high-concentration oxygen group. Cells in the normal control and model groups were cultured as normal.MAIN OUTCOME MEASURES: At day 7 after culture, glial fibrillary acidic protein,microtubule-associated protein 2, and galactocerebroside immunofluorescence staining were examined to

  12. Metabolic profiling of hypoxic cells revealed a catabolic signature required for cell survival.

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    Christian Frezza

    Full Text Available Hypoxia is one of the features of poorly vascularised areas of solid tumours but cancer cells can survive in these areas despite the low oxygen tension. The adaptation to hypoxia requires both biochemical and genetic responses that culminate in a metabolic rearrangement to counter-balance the decrease in energy supply from mitochondrial respiration. The understanding of metabolic adaptations under hypoxia could reveal novel pathways that, if targeted, would lead to specific death of hypoxic regions. In this study, we developed biochemical and metabolomic analyses to assess the effects of hypoxia on cellular metabolism of HCT116 cancer cell line. We utilized an oxygen fluorescent probe in anaerobic cuvettes to study oxygen consumption rates under hypoxic conditions without the need to re-oxygenate the cells and demonstrated that hypoxic cells can maintain active, though diminished, oxidative phosphorylation even at 1% oxygen. These results were further supported by in situ microscopy analysis of mitochondrial NADH oxidation under hypoxia. We then used metabolomic methodologies, utilizing liquid chromatography-mass spectrometry (LC-MS, to determine the metabolic profile of hypoxic cells. This approach revealed the importance of synchronized and regulated catabolism as a mechanism of adaptation to bioenergetic stress. We then confirmed the presence of autophagy under hypoxic conditions and demonstrated that the inhibition of this catabolic process dramatically reduced the ATP levels in hypoxic cells and stimulated hypoxia-induced cell death. These results suggest that under hypoxia, autophagy is required to support ATP production, in addition to glycolysis, and that the inhibition of autophagy might be used to selectively target hypoxic regions of tumours, the most notoriously resistant areas of solid tumours.

  13. Differential regulation of pro- and antiapoptotic proteins in fish adipocytes during hypoxic conditions.

    Science.gov (United States)

    Ekambaram, Padmini; Parasuraman, Parimala; Jayachandran, Tharani

    2016-06-01

    Worldwide, the frequencies and magnitudes of hypoxic events in estuarine waters have increased considerably over the past two decades. Fish populations are suitable indicators for the assessment of quality of aquatic ecosystems and often comprise a variety of adaptation systems by triggering oxidants, antioxidants and hypoxia-responsive signaling proteins. Signaling pathway may lead to cell survival or cell death which is fine-tuned by both positive and negative factors, which includes hypoxia-inducible factor-1α (HIF1α), heat-shock protein-70 (HSP70), phospho-c-Jun N-terminal kinase 1/2 (p-JNK1/2) and apoptosis signal-regulating kinase-1 (ASK1). In the present study, we attempt to determine stress-mediated signaling changes and molecular mechanism behind the cell survival by comparing adipocytes of fish from field hypoxic condition and laboratory-induced hypoxic condition (in vitro hypoxia). Comparison of field and laboratory studies in fish adipocytes showed differential expression of HIF1α, HSP70, p-JNK1/2 and ASK1 with altered oxidants and antioxidants. Further, the results also suggest that in vitro hypoxic conditions mimic field hypoxic conditions. Trends of hypoxia response were same in in vitro hypoxia of control adipocytes as in Ennore estuary, and hypoxia response was more pronounced in the test adipocytes under in vitro hypoxic condition. Results of the present work suggest that hypoxia is the major crusade of water pollutants affecting fish by differential regulation of pro- and antiapoptotic proteins probably through HSP70. This may play a vital role by providing cytoprotection in pollutant-induced stressed fish adipocytes substantiated by the in vitro hypoxic studies. PMID:26744268

  14. Opposing actions of chronic stress and chronic nicotine on striatal function in mice

    OpenAIRE

    Salas, Ramiro; De Biasi, Mariella

    2008-01-01

    Stress is a major risk factor in drug addiction development and relapse. Virtually all drugs of abuse act by increasing extracellular dopamine levels in the striatum. To gain an understanding of the interaction between stress and drug exposure, we studied the effects of concomitant chronic nicotine and chronic stress exposure on mouse striatal dopamine levels.

  15. Tolbutamide attenuates diazoxide-induced aggravation of hypoxic cell injury.

    Science.gov (United States)

    Pissarek, M; Reichelt, C; Krauss, G J; Illes, P

    1998-11-23

    ATP-dependent potassium (KATP) channels of neurons are closed in the presence of physiological levels of intracellular ATP and open when ATP is depleted during hypoxia or metabolic damage. The present study investigates hypoxic alterations of purine and pyrimidine nucleotide levels supposed to intracellularly modulate KATP channels. In addition, the effects of the KATP channel activator diazoxide and its antagonist tolbutamide were investigated on ATP, GTP, CTP and UTP levels in slices of the parietal cortex. Hypoxia was evoked by saturation of the medium with 95% N2-5% CO2 instead of 95% O2-5% CO2 for 5 min. Nucleotide contents were measured by anion-exchange HPLC in neutralized perchloric acid extracts obtained from slices frozen immediately at the end of incubation. Hypoxia per se decreased purine and pyrimidine nucleoside triphosphate contents. Thus, ATP and GTP contents were reduced to 69.9 and 77.6% of the respective normoxic levels. UTP and CTP contents were even more decreased (to 60.9 and 41.6%),, probably because the salvage pathway of these pyrimidine nucleotides is less effective than that of the purine nucleotides ATP and GTP. While tolbutamide (30 microM) had no effect on the hypoxia-induced decrease of nucleotides, diazoxide at 300, but not 30 microM aggravated the decline of ATP, UTP and CTP to 51.8, 37.5 and 28.5% of the contents observed at normoxia; GTP levels also showed a tendency to decrease after diazoxide application. Tolbutamide (300 microM) antagonized the effects of diazoxide (300 but not 30 microM aggravated the decline of ATP, UTP and CTP to 51.8, 37.5 and 28.5% of the contents observed at normoxia; GTP levels also showed a tendency to decrease after diazoxide application. Tolbutamide (300 microM) antagonized the effects of diazoxide (300 MicroM). Nucleoside diphosphate (ADP, GDP and UDP) levels were uniformly increased by hypoxia. There was no hypoxia-induced increase of ADP contents in the presence of tolbutamide (300 microM). The ATP

  16. A Piglet Model of Neonatal Hypoxic-Ischemic Encephalopathy.

    Science.gov (United States)

    Kyng, Kasper J; Skajaa, Torjus; Kerrn-Jespersen, Sigrid; Andreassen, Christer S; Bennedsgaard, Kristine; Henriksen, Tine B

    2015-05-16

    Birth asphyxia, which causes hypoxic-ischemic encephalopathy (HIE), accounts for 0.66 million deaths worldwide each year, about a quarter of the world's 2.9 million neonatal deaths. Animal models of HIE have contributed to the understanding of the pathophysiology in HIE, and have highlighted the dynamic process that occur in brain injury due to perinatal asphyxia. Thus, animal studies have suggested a time-window for post-insult treatment strategies. Hypothermia has been tested as a treatment for HIE in pdiglet models and subsequently proven effective in clinical trials. Variations of the model have been applied in the study of adjunctive neuroprotective methods and piglet studies of xenon and melatonin have led to clinical phase I and II trials(1,2). The piglet HIE model is further used for neonatal resuscitation- and hemodynamic studies as well as in investigations of cerebral hypoxia on a cellular level. However, it is a technically challenging model and variations in the protocol may result in either too mild or too severe brain injury. In this article, we demonstrate the technical procedures necessary for establishing a stable piglet model of neonatal HIE. First, the newborn piglet (< 24 hr old, median weight 1500 g) is anesthetized, intubated, and monitored in a setup comparable to that found in a neonatal intensive care unit. Global hypoxia-ischemia is induced by lowering the inspiratory oxygen fraction to achieve global hypoxia, ischemia through hypotension and a flat trace amplitude integrated EEG (aEEG) indicative of cerebral hypoxia. Survival is promoted by adjusting oxygenation according to the aEEG response and blood pressure. Brain injury is quantified by histopathology and magnetic resonance imaging after 72 hr.

  17. Fit for high altitude: are hypoxic challenge tests useful?

    Directory of Open Access Journals (Sweden)

    Matthys Heinrich

    2011-02-01

    Full Text Available Abstract Altitude travel results in acute variations of barometric pressure, which induce different degrees of hypoxia, changing the gas contents in body tissues and cavities. Non ventilated air containing cavities may induce barotraumas of the lung (pneumothorax, sinuses and middle ear, with pain, vertigo and hearing loss. Commercial air planes keep their cabin pressure at an equivalent altitude of about 2,500 m. This leads to an increased respiratory drive which may also result in symptoms of emotional hyperventilation. In patients with preexisting respiratory pathology due to lung, cardiovascular, pleural, thoracic neuromuscular or obesity-related diseases (i.e. obstructive sleep apnea an additional hypoxic stress may induce respiratory pump and/or heart failure. Clinical pre-altitude assessment must be disease-specific and it includes spirometry, pulsoximetry, ECG, pulmonary and systemic hypertension assessment. In patients with abnormal values we need, in addition, measurements of hemoglobin, pH, base excess, PaO2, and PaCO2 to evaluate whether O2- and CO2-transport is sufficient. Instead of the hypoxia altitude simulation test (HAST, which is not without danger for patients with respiratory insufficiency, we prefer primarily a hyperoxic challenge. The supplementation of normobaric O2 gives us information on the acute reversibility of the arterial hypoxemia and the reduction of ventilation and pulmonary hypertension, as well as about the efficiency of the additional O2-flow needed during altitude exposure. For difficult judgements the performance of the test in a hypobaric chamber with and without supplemental O2-breathing remains the gold standard. The increasing numbers of drugs to treat acute pulmonary hypertension due to altitude exposure (acetazolamide, dexamethasone, nifedipine, sildenafil or to other etiologies (anticoagulants, prostanoids, phosphodiesterase-5-inhibitors, endothelin receptor antagonists including mechanical aids to

  18. Detection of hypoxic fractions in murine tumors by comet assay: Comparison with other techniques

    International Nuclear Information System (INIS)

    The alkaline comet assay was used to detect the hypoxic fractions of murine tumors. A total of four tumor types were tested using needle aspiration biopsies taken immediately after a radiation dose of 15 Gy. Initial studies confirmed that the normalized tail moment, a parameter reflecting single-strand DNA breaks induced by the radiation, was linearly related to radiation dose. Further, it was shown that for a mixed population (1:1) of cells irradiated under air-breathing or hypoxic conditions, the histogram of normal tail moment values obtained from analyzing 400 cells in the population had a double peak which, when fitted with two Gaussian distributions, gave a good estimate of the proportion of the two subpopulations. For the four tumor types, the means of the calculated hypoxic fractions from four or five individual tumors were 0.15 ± 0.04 for B16F1, 0.08 ± 0.04 for KHT-LP1, 0.17 ± 0.04 for RIF-1 and 0.04 ± 0.01 for SCCVII. Analysis of variance showed that the hypoxic fraction in KHT-LP1 tumors is significantly lower than those of the other three tumors (P = 0.026) but that there is no significant difference in hypoxic fraction between B16F1, RIF-1 and SCCVII tumors (P = 0.574). Results from multiple samples taken from each of five RIF-1 tumors showed that the intertumor heterogeneity of hypoxic fractions was greater than that within the same tumor. The mean hypoxic fraction obtained using the comet assay for the four tumor types was compared with the hypoxic fraction determined by the clonogenic assay, or median pO2 values, or [3H]misonidazole binding in the same tumor types. The values of hypoxic fraction obtained with the comet assay were two to four times lower than those measured by the paired survival method. Preliminary results obtained with a dose of 5 Gy were consistent with those obtained using 15 Gy. These results suggest the further development of the comet assay for clinical studies. 21 refs., 7 figs., 5 tabs

  19. Inhibition of inflammatory mediator release from microglia can treat ischemic/hypoxic brain injury

    Institute of Scientific and Technical Information of China (English)

    Huaibo Wang; Weitao Guo; Hongliang Liu; Rong Zeng; Mingnan Lu; Ziqiu Chen; Qixian Xiao

    2013-01-01

    Interleukin-1α and interleukin-1β aggravate neuronal injury by mediating the inflammatory reaction following ischemic/hypoxic brain injury. It remains unclear whether interleukin-1α and interleukin-1β are released by microglia or astrocytes. This study prepared hippocampal slices that were subsequently subjected to oxygen and glucose deprivation. Hematoxylin-eosin staining verified that neurons exhibited hypoxic changes. Results of enzyme-linked immunosorbent assay found that interleukin-1α and interleukin-1β participated in this hypoxic process. Moreover, when hypoxic injury occurred in the hippocampus, the release of interleukin-1α and interleukin-1β was mediated by the P2X4 receptor and P2X7 receptor. Immunofluorescence staining revealed that during ischemia/hypoxia, the P2X4 receptor, P2X7 receptor, interleukin-1α and interleukin-1β expression was detectable in rat hippocampal microglia, but only P2X4 receptor and P2X7 receptor expression was detected in astrocytes. Results suggested that the P2X4 receptor and P2X7 receptor, respectively, mediated interleukin-1α and interleukin-1β released by microglia, resulting in hippocampal ischemic/hypoxic injury. Astrocytes were activated, but did not synthesize or release interleukin-1α and interleukin-1β.

  20. Acute effect of tetrandrine pulmonary targeting microspheres on hypoxic pulmonary hypertension in rats

    Institute of Scientific and Technical Information of China (English)

    程德云; 陈文彬; 莫晓能

    2002-01-01

    Objective To assess the effect of tetrandrine (Tet) pulmonary targeting microspheres on hypoxic pulmonary hypertension and evaluate its selective action on pulmonary circulation. Methods Twenty rats were exposed to hypoxic conditions for 3 weeks. Ten rats were used as normoxic controls. We administered Tet pulmonary targeting microspheres to 10 hypoxic rats and Tet aqueous solution to 10 hypoxic rats and the 10 control rats. Mean pulmonary arterial pressure (mPAP) was measured by a right cardiac catheterization, and mean systemic blood pressure (mSBP) was measured by left femoral catheterization. Results Rats exposed to hypoxia developed pulmonary hypertension. The decrease in mPAP in rats treated with Tet pulmonary targeting microspheres was significantly greater than that in rats receiving Tet aqueous solution (P<0.05), and the effects were longer with Tet pulmonary targeting microspheres. Moreover, Tet pulmonary targeting microspheres, unlike Tet aqueous solution, did not decrease mSBP. Conclusion Tet pulmonary targeting microspheres were more effective than Tet aqueous solution in treating hypoxic pulmonary hypertension and acted selectively on the pulmonary circulation.

  1. Options for managing hypoxic blackwater events in river systems: a review.

    Science.gov (United States)

    Kerr, Janice L; Baldwin, Darren S; Whitworth, Kerry L

    2013-01-15

    Blackwater events are characterised by a high concentration of dissolved organic carbon in the water column. They occur naturally in lowland rivers with forested floodplains and bring a variety of benefits to both aquatic and floodplain biota. However, particularly when accompanied by high temperatures, respiration of the organic carbon may cause blackwater to become hypoxic. This may lead to a range of lethal and sub-lethal effects on the aquatic biota. We review the current scientific knowledge concerning the management of blackwater and hypoxia, and examine how this knowledge may be applied to the management of hypoxic blackwater events in lowland river systems. A range of management options, which aim to either prevent the development of hypoxic blackwater or to reintroduce oxygen into deoxygenated waters, are reported. Mitigation options that may be applicable to lowland river systems include manipulating the season and magnitude of floods in regulated rivers, increasing roughness in flow paths, establishing oxygenated refugia for aquatic biota and introducing hydraulic structures that promote turbulence and re-aeration. With climatic changes trending towards a scenario where extreme events leading to the development of hypoxic blackwater are more probable, it is now vital to validate and optimise management options on local and regional scales and work towards closing knowledge gaps. With judicious management of regulated rivers, it is possible to minimise the impacts of hypoxic flows while preserving the benefits brought to floodplain and river ecosystems by seasonal flooding and carbon exchange. PMID:23137913

  2. Posttranscriptional control of the hypoxic response by RNA-binding proteins and microRNAs

    Directory of Open Access Journals (Sweden)

    Myriam eGorospe

    2011-07-01

    Full Text Available Mammalian gene expression patterns change profoundly in response to low oxygen levels. These changes in gene expression programs are strongly influenced by post-transcriptional mechanisms mediated by mRNA-binding factors: RNA-binding proteins (RBPs and microRNAs (miRNAs. Here, we review the RBPs and miRNAs that modulate mRNA turnover and translation in response to hypoxic challenge. RBPs such as HuR (human antigen R, PTB (polypyrimidine tract-binding protein, heterogeneous nuclear ribonucleoproteins (hnRNPs, tristetraprolin, nucleolin, iron-response element binding proteins (IRPs, and cytoplasmic polyadenylation-element-binding proteins (CPEBs, selectively bind to numerous hypoxia-regulated transcripts and play a major role in establishing hypoxic gene expression patterns. MiRNAs including miR-210, miR-373, and miR-21 associate with hypoxia-regulated transcripts and further modulate the levels of the encoded proteins to implement the hypoxic gene expression profile. We discuss the potent regulation of hypoxic gene expression by RBPs and miRNAs and their integrated actions in the cellular hypoxic response.

  3. [A comparison of a neuroprotective effects of hypoxic postconditioning and cerebrolysin in the experimental model].

    Science.gov (United States)

    Rybnikova, E A; Vorob'ev, M G; Pivina, S G; Samoĭlov, M O

    2013-01-01

    Hypoxic postconditioning using episodes of mild hypobaric hypoxia is a new neuroprotective technique. We compared the neuroprotective efficacy of hypoxic postconditioning and cerebrolysin in a model of posthypoxic pathology in rats. Animals that survived the severe hypoxia (180 Torr, 3 h) were exposed to hypoxic postconditioning or received cerebrolysin. Postconditioning prevented the injury and loss of hippocampal (fields CA1, CA4) and neocortical neurons whereas cerebrolysin was protective only for CA4 and the neocortex. Besides that, postconditioning, unlike cerebrolysin, led to the complete functional rehabilitation from the severe hypoxia by normalizing the level of anxiety and the pituitary-adrenal axis activity. The findings demonstrate that the elaborated postconditioning technique might provide useful tool for therapy of posthypoxic pathology and stroke. PMID:23528584

  4. Effects of posture on blood flow diversion by hypoxic pulmonary vasoconstriction in dogs

    Science.gov (United States)

    Walther, S. M.; Domino, K. B.; Hlastala, M. P.

    1998-01-01

    We used differential excretion of sulphur hexafluoride from the left and right lung to measure blood flow diversion by hypoxic pulmonary vasoconstriction (HPV) in the prone and supine positions in dogs (n = 9). Gas exchange was assessed using the multiple inert gas elimination technique. Blood flow diversion from the hypoxic (3% oxygen) left lung was mean 70.7 (SD 11.2)% in the supine compared with 57.0 (12.1)% in the prone position (P perfusion to low VA/Q regions (P ventilation to high VA/Q regions (P < 0.05). We conclude that flow diversion by hypoxic pulmonary vasoconstriction is greater in the supine position. This effect could contribute to the variable response in gas exchange with positioning in patients with ARDS.

  5. Immunocytochemical labelling of aerobic and hypoxic mammalian cells using a platinated derivative of EF5.

    Science.gov (United States)

    Matthews, J; Adomat, H; Farrell, N; King, P; Koch, C; Lord, E; Palcic, B; Poulin, N; Sangulin, J; Skov, K

    1996-07-01

    The monoclonal antibody ELK3-51 was previously developed to detect adducts of the 2-nitroimidazole EF5. Direct immunofluorescence was used to detect adducts of EF5 or of a platinated derivative cis-[PtCl2(NH3)EF5] in SCCVII cells treated under aerobic or hypoxic conditions. Fluorescence measurements of these cells using both image and flow cytometric methods were compared, giving similar profiles. Platination significantly decreased immunofluorescence levels (approximately 4-fold less than EF5) after 3 h in hypoxia, but also increased levels after exposure in air (approximately 1.5 x) such that the hypoxic ratio decreased from approximately 50 to approximately 13. Platinated EF5 also showed significantly greater cytotoxicity than its parent in both aerobic and hypoxic cells. These results are consistent with targeting of EF5 to DNA, which was confirmed qualitatively by confocal microscopy. PMID:8763880

  6. [A comparison of a neuroprotective effects of hypoxic postconditioning and cerebrolysin in the experimental model].

    Science.gov (United States)

    Rybnikova, E A; Vorob'ev, M G; Pivina, S G; Samoĭlov, M O

    2013-01-01

    Hypoxic postconditioning using episodes of mild hypobaric hypoxia is a new neuroprotective technique. We compared the neuroprotective efficacy of hypoxic postconditioning and cerebrolysin in a model of posthypoxic pathology in rats. Animals that survived the severe hypoxia (180 Torr, 3 h) were exposed to hypoxic postconditioning or received cerebrolysin. Postconditioning prevented the injury and loss of hippocampal (fields CA1, CA4) and neocortical neurons whereas cerebrolysin was protective only for CA4 and the neocortex. Besides that, postconditioning, unlike cerebrolysin, led to the complete functional rehabilitation from the severe hypoxia by normalizing the level of anxiety and the pituitary-adrenal axis activity. The findings demonstrate that the elaborated postconditioning technique might provide useful tool for therapy of posthypoxic pathology and stroke.

  7. Effects of minocycline on learning and memory of mice following ischemic-hypoxic cerebral injuries

    Institute of Scientific and Technical Information of China (English)

    Hongling Fan; Yuanyin Zheng; Lijuan Xu; Zhichao Zhong; Shining Cai; Shuling Zhang; Quanzhong Chang

    2012-01-01

    An ischemic-hypoxic animal model was established using right common carotid artery occlusions and inhalation of low concentrations of oxygen in mice. At 10 days after the ischemic-hypoxic injuries, saline-treated mice exhibited significantly prolonged escape latencies in water-maze tests and significantly shorter memory latencies and more mistakes in step-down tests. In contrast, mice treated with 5 mg/kg minocycline exhibited significant reversals of each of these effects compared with the saline-treated control mice. Moreover, we found that minocycline can relieve brain water content and morphological changes in mice following ischemic-hypoxic cerebral injuries. Accordingly, our findings indicate that minocycline provides some protections against the deleterious effects of these injuries in mice.

  8. Blood immunological parameters upon hypoxic-ischemic injuries of central nervous system in newborns and infants

    Directory of Open Access Journals (Sweden)

    Gulomjan Khalimbetov

    2012-05-01

    Full Text Available The paper studies interrelation between immune system condition and circulating concentrations of neuropeptides and neuron-specific enolase (NSE upon perinatal pathology in newborns and infants. Reactivity of cytokine and interleukin links of immune systems was found varying in newborns and infants with CNS hypoxic-ischemic pathology, accompanied by psychomotor retardation, a psycho-speech disorder, emotional and behavioral disorders (EBD and paroxysmal syndrome. At admission irrespectively of a syndrome type in the patients with CNS hypoxic-ischemic pathology, as compared with the patients in the control group, circulating TNF-α and IL-1 were found increased by 3.4-4.1 and 6.4-7.9 times, respectively. Release of S100 protein and NSE seems to be the underlying mechanism for enhancement of synthesis and/or release of TNF-α and IL-1 into circulation of patients with CNS hypoxic-ischemic pathology.

  9. Perinatal hypoxic-ischemic encephalopathy: severity determinants and outcomes

    Directory of Open Access Journals (Sweden)

    Liliana Teixeira

    2014-06-01

    Full Text Available Perinatal hypoxic-ischemic encephalopathy (HIE after perinatal asphyxia is one of the most critical pathologic conditions in neonatal medicine due to the potential for neurological sequelae in later life. The aim of our study is to identify the factors that are associated with a higher degree of severity in HIE and evaluate the outcomes. We performed a retrospective study of all newborns with HIE treated at our neonatal intensive care unit (NICU from January 2010 to December 2013. Data collected include information about prenatal period, peripartum period, demographic characteristics, admission and evolution during NICU stay and outcomes (assessed in three different times: at discharge, at 6-9 months and 18 months. Forty seven newborns were enrolled in our study, 11 (23.4% with mild HIE, 21 (44.7% with moderate HIE and 15 (31.9% with severe HIE. Prenatal, perinatal and demographic data showed no statistically significant differences between groups. Statistically significant differences were found in values of Thompson score (p < 0.0001, abnormal aEEG/EEG at admission (p = 0.025 and at 48 hours (p = 0.018, need of mechanical ventilation (p = 0.004, acute renal failure (p = 0.002 and length of stay (p = 0.038 with high rates in the moderate and severe HIE groups. Regarding the outcomes, statistically significant differences were found in the prevalence of death (p = 0.010; need of antiepileptic drugs at discharge (p = 0.001; motor deficits requiring physiotherapy (p = 0.046, abnormal deep tendon reflex (p = 0.006 and need of antiepileptic drugs (p = 0.001 at 6-9 months follow-up; and cerebral palsy with cognitive impairment at 18 months (p = 0.041 with high rates in the severe HIE group. These results suggest that Thompson score, abnormal aEEG/EEG at admission and at 48 hours, mechanical ventilation, acute renal failure and length of stay are associated with more severe HIE. We also concluded that more severe HIE reflects worse outcomes whereas

  10. Options for Managing Hypoxic Blackwater in River Systems: Case Studies and Framework

    Science.gov (United States)

    Whitworth, Kerry L.; Kerr, Janice L.; Mosley, Luke M.; Conallin, John; Hardwick, Lorraine; Baldwin, Darren S.

    2013-10-01

    Hypoxic blackwater events occur when large amounts of organic material are leached into a water body (e.g., during floodplain inundation) and rapid metabolism of this carbon depletes oxygen from the water column, often with catastrophic effects on the aquatic environment. River regulation may have increased the frequency and severity of hypoxic blackwater events in lowland river systems, necessitating management intervention to mitigate the impacts of these events on aquatic biota. We examine the effectiveness of a range of mitigation interventions that have been used during large-scale hypoxic blackwater events in the Murray-Darling Basin, Australia and that may be applicable in other environments at risk from hypoxic blackwater. Strategies for hypoxia mitigation include: delivery of dilution flows; enhancement of physical re-aeration rates by increasing surface turbulence; and diversion of blackwater into shallow off-channel storages. We show that the impact of dilution water delivery is determined by relative volumes and water quality and can be predicted using simple models. At the dilution water inflow point, localized oxygenated plumes may also act as refuges. Physical re-aeration strategies generally result in only a small increase in dissolved oxygen but may be beneficial for local refuge protection. Dilution and natural re-aeration processes in large, shallow lake systems can be sufficient to compensate for hypoxic inflows and water processed in off-channel lakes may be able to be returned to the river channel as dilution flows. We provide a set of predictive models (as electronic supplementary material) for estimation of the re-aeration potential of intervention activities and a framework to guide the adaptive management of future hypoxic blackwater events.

  11. Study of capillary network directionality and irrigation of hypoxic tissue in an angiogenesis lattice model

    Science.gov (United States)

    Moglia, Belén; Guisoni, Nara; Albano, Ezequiel V.

    2013-12-01

    To shed light on the understanding of the angiogenesis process, we study a simplified lattice model for the capillary network formation between an existing blood vessel and an initially hypoxic tissue. We consider that the cells of the tissue surface can release growth factors that will diffuse, leading to the formation of new capillaries that ultimately arrive at the tissue. Additionally, we consider the local production of growth factors by the growing capillary network. We also propose the existence of an inhibition mechanism at the hypoxic surface, i.e., a fixed number of neighboring sites of an already irrigated site of the hypoxic tissue stop releasing growth factors due to the arrival of nutrients. Particularly, the goal of this work is to study the effect of the release of local growth factors and the inhibition mechanism on properties such as the directionality of the growing network and the irrigation of the hypoxic tissue. Therefore we propose the quantification of these two relevant features for angiogenesis modeling. We establish a relationship between the model behavior without the release of local growth factors in the presence of the inhibition mechanism and a normal angiogenesis process. In this situation, the model gives a directional capillary network and a good irrigation of the hypoxic tissue. On the other hand, for a large number of released local growth factors in the absence of the inhibition mechanism, the model could be appropriate for the description of tumor angiogenesis. In this case, the model provides a rather small directionality for the growing structure, with a worse degree of irrigation of the hypoxic tissue, as well as a more tortuous capillary network with many closed branches and loops.

  12. pH-responsive hybrid quantum dots for targeting hypoxic tumor siRNA delivery.

    Science.gov (United States)

    Zhu, HongYan; Zhang, ShengYu; Ling, Yong; Meng, GuoLiang; Yang, Yu; Zhang, Wei

    2015-12-28

    Hypoxia is a characteristic of cancer and plays a key role in tumorigenesis, angiogenesis and resistance to cancer therapies. SiRNA treatment is effective against hypoxic tumors by gene silencing. However, siRNA delivery to the hypoxic regions of solid tumors still presents a challenge due to the distance from blood vessels and the increased presence of efflux transporters. Therefore, tumor therapies would be improved through the immediate development of an effective siRNA delivery system to hypoxic regions. To this end, we synthesized a system to deliver HIF-1α siRNA into hypoxic tumor cells. The system consists of a functional shell composed of 2-deoxyglucose (DG)-polyethylene glycol (PEG) connected with the compound of lipoic acid, lysine and 9-poly-d-arginine (LA-Lys-9R) by a hydrazone bond and a core of CdTe quantum dots (QDs). The molecular structure of DG-PEG-LA-Lys-9R was confirmed by liquid chromatography-mass spectrometry (LC-MS), nuclear magnetic resonance (NMR) spectroscopy, Fourier transform infrared spectroscopy (FTIR), and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The multifunctional CdTe QDs measured approximately 200 nm and showed excellent biocompatibility, perfect siRNA binding capability and enhanced hypoxic tumor targeting. Importantly, the system described here is pH-responsive with a hydrazone bond; therefore, it avoids GLUT1 receptor-mediated endocytic recycling, resulting in irreversible delivery of the siRNA. We used Western blots to confirm the superior gene silencing efficiency induced by the DG-PEG-LA-Lys-9R with hydrazone modified CdTe QDs. Here, we demonstrate high efficacy of the siRNA tumor delivery system using in vitro and in vivo experiments. In addition, these studies demonstrate that pH-responsive hybrid quantum dots show improved antitumor efficacy with decreased organ toxicity, indicating a promising siRNA delivery system for hypoxic cancer therapy. PMID:26590349

  13. Chronic THC intake modifies fundamental cerebellar functions

    OpenAIRE

    Stella, Nephi

    2013-01-01

    Delta9-tetrahydrocannabinol (THC), the principal bioactive component in the Cannabis plant, is truly a captivating drug. Acute and chronic THC intake produces a spectrum of biological effects ranging from transient psychotropic effects to prolonged medicinal benefits, many of which have been fostered for centuries by our society. In the July 2013 issue of the JCI, Cutando et al. combined mouse genetics with classic mouse behavioral analysis to deepen our understanding of the...

  14. Reversing hypoxic cell chemoresistance in vitro using genetic and small molecule approaches targeting hypoxia inducible factor-1

    DEFF Research Database (Denmark)

    Brown, Louisa M; Cowen, Rachel L; Debray, Camille;

    2006-01-01

    The resistance of hypoxic cells to conventional chemotherapy is well documented. Using both adenovirus-mediated gene delivery and small molecules targeting hypoxia-inducible factor-1 (HIF-1), we evaluated the impact of HIF-1 inhibition on the sensitivity of hypoxic tumor cells to etoposide. The g...

  15. Analysis of 127 peripartum hypoxic brain injuries from closed claims registered by the Danish Patient Insurance Association

    DEFF Research Database (Denmark)

    Bock, J.; Christoffersen, J.K.; Hedegaard, M.;

    2008-01-01

    BACKGROUND: One of the most feared complications in medicine is hypoxic brain damage to a newborn. The authors investigated the circumstances of registered peripartum hypoxic brain injuries in order to identify potential opportunities to improve patient safety and prevent injuries. METHODS: The a...

  16. Prolonged hypoxic culture and trypsinization increase the pro-angiogenic potential of human adipose tissue-derived stem cells

    DEFF Research Database (Denmark)

    Rasmussen, Jeppe Grøndahl; Frøbert, Ole; Pilgaard, Linda;

    2011-01-01

    Transplantation of mesenchymal stromal cells (MSC), including adipose tissue-derived stem cells (ASC), is a promising option in the treatment of vascular disease. Short-term hypoxic culture of MSC augments secretion of anti-apoptotic and angiogenic cytokines. We hypothesized that prolonged hypoxic...

  17. Influence of Prostaglandin Synthesis Inhibitors on Pulmonary Vasodilatory Effects of Hydralazine in Dogs with Hypoxic Pulmonary Vasoconstriction

    OpenAIRE

    Rubin, Lewis J.; Lazar, Jeffrey D.

    1981-01-01

    To determine whether hydralazine, a systemic vasodilator, exerted a similar effect on the pulmonary circulation, we studied the circulatory changes in dogs during three interventions: (a) the control state during room air ventilation; (b) during continuous hypoxic ventilation with 10% oxygen, and maintaining continuous hypoxic ventilation; and (c) after 1 mg/kg hydralazine intravenously.

  18. Cerebral volumetric changes induced by prolonged hypoxic exposure and whole-body exercise

    OpenAIRE

    Rupp, Thomas; Jubeau, Marc; Lamalle, Laurent; Warnking, Jan M.; Guillaume Y Millet; Wuyam, Bernard; Esteve, François; Levy, Patrick; Krainik, Alexandre; Verges, Samuel

    2014-01-01

    The present study assessed the isolated and synergetic effects of hypoxic exposure and prolonged exercise on cerebral volume and subedema and symptoms of acute mountain sickness (AMS). Twelve healthy males performed three semirandomized blinded 11-hour sessions with (1) an inspiratory oxygen fraction (FiO2) of 12% and 4-hour cycling, (2) FiO2=21% and 4-hour cycling, and (3) FiO2=8.5% to 12% at rest (matching arterial oxygen saturation measured during the first hypoxic session). Volumetric, ap...

  19. Color Doppler ultrasonography in full term neonates with hypoxic ischemic encephalopathy and prediction of outcome

    OpenAIRE

    Naglaa Fathy Barseem; Hassan Said Badr; Mohamed Shawky Abdullah

    2016-01-01

    Background: Impaired cerebral circulation plays the main role in the pathogenesis of hypoxic-ischemic brain injury in neonates. Objectives: We aimed to determine blood flow parameters via color Doppler ultrasonography in full-term neonates with hypoxic-ischemic (HI) brain injury at 12 h postpartum and the correlation of these parameters with long-term outcomes at the age of 1-year. Design and subjects: Our study included 40 full term neonates with HIE (Patients group) and 25 healthy full term...

  20. 玻璃苣醇提物对慢性抑郁模型小鼠脑组织中神经递质的影响%Effects of the ethanol extractive of Borago officinalis on neurotransmitter in the brain tissue of mouse model of chronic depression

    Institute of Scientific and Technical Information of China (English)

    刚宏林; 何志一; 刘相辉; 马跃

    2012-01-01

    目的:通过建立慢性应激小鼠抑郁模型,观察玻璃苣对慢性应激抑郁模型小鼠脑内5-羟色胺、去甲肾上腺素(NE)、多巴胺3种单胺类神经递质的影响,初步探讨玻璃苣对抑郁模型小鼠的影响及其作用机制.方法:利用孤养和长期不可预见性温和应激(CUMS)建立慢性应激小鼠抑郁模型,采用酶联免疫吸附测定法(ELISA)测定慢性应激抑郁模型小鼠脑内单胺类神经递质的变化.结果:模型组小鼠脑内5-羟色胺、NE、多巴胺含量明显低于正常组;与模型组相比,玻璃苣醇提物高、中剂量组小鼠脑内5-羟色胺、NE、多巴胺的含量均有升高,且差异有统计学意义.玻璃苣醇提物低剂量组小鼠脑内5-羟色胺、NE、多巴胺的含量也有升高趋势,但差异无统计学意义.结论:玻璃苣能够提高慢性应激抑郁模型小鼠脑内单胺类神经递质(5-羟色胺、NE、多巴胺)的含量,玻璃苣对小鼠脑内神经递质的作用可能是其对抑郁模型小鼠产生影响的可能机制.%Objective; The effects of the extractive of Borago officinalis on norepinephrine (NE) ,dopa-mine and 5-hydroxytryptamine(5-HT)in mouse model of depression with chronic stress were investigated after establishing of chronic stress mouse models of depression ; and to discuss its prevention and cure effects and their possible mechanisms. Methods; Established chronic stress mouse models of depression by using singly housed and long-trem unpredictable mild stress ( CUMS) ; and to determine the change of brain mono-amine neurotransmitters of chronic stress depression model mice by using enzyme -linked immunosorbent assay (ELISA). Results; The monoamine neurotransmitters (5-HT,NE, dopamine) contents in model mice were significantly less than normal group. The high, medium group of ethanol extractive from Borago offici-nalis all could increase the contents of 5-HT,NE,dopamine of mice with chronic stress depression ;and the low group of

  1. Effects of Salvia miltiorrhiza extracts on rat hypoxic pulmonary hypertension, heme oxygenase-1 and nitric oxide synthase

    Institute of Scientific and Technical Information of China (English)

    陈颖; 阮英茆; 李莉; 褚雁; 徐新林; 王清峙; 周晓梅

    2003-01-01

    Objective To investigate the effects of Salvia miltiorrhiza (SM) extracts on the expression of heme oxygenase-1 (HO-1) and nitric oxide synthase (NOS) in small pulmonary arteries (SPAs) of rats with chronic hypoxia. Methods After two weeks of hypoxia, rats were treated with diltiazem, then small, medium, and large doses of SM extracts. The lungs were tested for the expression and distribution of HO-1, endothelial NOS (eNOS) and inducible NOS (iNOS) by using immunohistochemistry and Western blot method. Results Median and large doses of SM extracts significantly reduced hypoxia-induced media thickening in the SPA (similar with diltiazem), recovered repaired ultrastructure injury, decreased HO-1 and iNOS levels, and increased eNOS expression in the SPA. Conclusions Median and large doses of SM extracts play significant roles in inhibiting structural remodeling in rats with hypoxic pulmonary hypertension. These effects might attribute to the suppression of HO-1 and iNOS, and the promotion of eNOS expression under the conditions of hypoxia.

  2. Gaze beats mouse

    DEFF Research Database (Denmark)

    Mateo, Julio C.; San Agustin, Javier; Hansen, John Paulin

    2008-01-01

    pointing was faster than mouse pointing, while maintaining a similar error rate. EMG and mouse-button selection had a comparable performance. From analyses of completion time, throughput and error rates, we concluded that the combination of gaze and facial EMG holds potential for outperforming the mouse....

  3. Normobaric oxygen as a sensitizer of hypoxic tumor cells

    International Nuclear Information System (INIS)

    A series of experiments have been performed to determine the relative radiosensitivities of a mouse mammary tumor (CA NT) irradiated in 100% normobaric oxygen or in air, using clinically relevant dose-fractionation schedules. The results demonstrate that normobaric oxygen is a potent radiosensitizer, its effect being more marked with smaller size fractions. Enhancement ratios (ER) of 1.23 to 1.45 were obtained. By contrast, no significant benefit was seen with single doses (ER = 1.05 +/- 0.14). The degree of radiosensitization with oxygen, in these fractionated regimens, is greater than that reported for the chemical radiosensitizer, misonidazole. It therefore seems appropriate to re-examine the clinical potential of normobaric oxygen and to consider how the conditions of normobaric radiotherapy achieved in the laboratory can be translated to man

  4. Changes in the activity levels of glutamine synthetase, glutaminase and glycogen synthetase in rats subjected to hypoxic stress

    Science.gov (United States)

    Vats, P.; Mukherjee, A. K.; Kumria, M. M. L.; Singh, S. N.; Patil, S. K. B.; Rangnathan, S.; Sridharan, K.

    Exposure to high altitude causes loss of body mass and alterations in metabolic processes, especially carbohydrate and protein metabolism. The present study was conducted to elucidate the role of glutamine synthetase, glutaminase and glycogen synthetase under conditions of chronic intermittent hypoxia. Four groups, each consisting of 12 male albino rats (Wistar strain), were exposed to a simulated altitude of 7620 m in a hypobaric chamber for 6 h per day for 1, 7, 14 and 21 days, respectively. Blood haemoglobin, blood glucose, protein levels in the liver, muscle and plasma, glycogen content, and glutaminase, glutamine synthetase and glycogen synthetase activities in liver and muscle were determined in all groups of exposed and in a group of unexposed animals. Food intake and changes in body mass were also monitored. There was a significant reduction in body mass (28-30%) in hypoxia-exposed groups as compared to controls, with a corresponding decrease in food intake. There was rise in blood haemoglobin and plasma protein in response to acclimatisation. Over a three-fold increase in liver glycogen content was observed following 1 day of hypoxic exposure (4.76+/-0.78 mg.g-1 wet tissue in normal unexposed rats; 15.82+/-2.30 mg.g-1 wet tissue in rats exposed to hypoxia for 1 day). This returned to normal in later stages of exposure. However, there was no change in glycogen synthetase activity except for a decrease in the 21-days hypoxia-exposed group. There was a slight increase in muscle glycogen content in the 1-day exposed group which declined significantly by 56.5, 50.6 and 42% following 7, 14, and 21 days of exposure, respectively. Muscle glycogen synthetase activity was also decreased following 21 days of exposure. There was an increase in glutaminase activity in the liver and muscle in the 7-, 14- and 21-day exposed groups. Glutamine synthetase activity was higher in the liver in 7- and 14-day exposed groups; this returned to normal following 21 days of exposure

  5. Temporal Rac1 - HIF-1 crosstalk modulates hypoxic survival of aged neurons.

    Science.gov (United States)

    Güntert, Tanja; Gassmann, Max; Ogunshola, Omolara O

    2016-07-01

    Neurodegenerative diseases are frequently associated with hypoxic conditions. During hypoxia the neuronal cytoskeleton is rapidly reorganized and such abnormalities are directly linked to adverse outcomes. Besides their roles as master regulators of the cytoskeleton, the Rho GTPases are also involved in cellular processes stimulated by hypoxic stress. We investigated the contribution of Rac1-mediated signaling to hypoxic responses of mature neurons using primary cortical cells cultured for 17 days in vitro. We show Rac1 is both upregulated and activated during hypoxia. Pharmacological inhibition of Rac1, but not RhoA, completely abrogated hypoxic HIF-1α stabilization and expression of the HIF-1 targets VEGF and GLUT1. Furthermore activity of JNK and GSK3β were also highly dependent on Rac1 activity and biphasic effects were observed after 6 and 24h of exposure. Notably, inhibition of either pathway suppressed HIF-1α accumulation. Although inhibition of Rac1 did not affect neuronal viability during acute exposure cell death was strongly induced after 24h revealing a time-dependent effect of Rac1 signaling on survival. Thus hypoxia-activated Rac1 is critical for neuronal HIF-1α stabilization and survival during oxygen deprivation via integration of complex signaling cascades. PMID:27018294

  6. Hypoxic remodelling of Ca{sup 2+} stores does not alter human cardiac myofibroblast invasion

    Energy Technology Data Exchange (ETDEWEB)

    Riches, K.; Hettiarachchi, N.T.; Porter, K.E. [Leeds Institute for Genetics, Health and Therapeutics, Faculty of Medicine and Health, University of Leeds, Leeds LS2 9JT (United Kingdom); Peers, C., E-mail: c.s.peers@leeds.ac.uk [Leeds Institute for Genetics, Health and Therapeutics, Faculty of Medicine and Health, University of Leeds, Leeds LS2 9JT (United Kingdom)

    2010-12-17

    Research highlights: {yields} Bradykinin promotes migration and proliferation of myofibroblasts. {yields} Such activity is Ca{sup 2+}-dependent and occurs under hypoxic conditions. {yields} Hypoxia increased myofibroblast Ca{sup 2+} stores but not influx evoked by bradykinin. {yields} Myofibroblast migration and proliferation was unaffected by hypoxia. -- Abstract: Cardiac fibroblasts are the most abundant cell type in the heart, and play a key role in the maintenance and repair of the myocardium following damage such as myocardial infarction by transforming into a cardiac myofibroblast (CMF) phenotype. Repair occurs through controlled proliferation and migration, which are Ca{sup 2+} dependent processes, and often requires the cells to operate within a hypoxic environment. Angiotensin converting enzyme (ACE) inhibitors reduce infarct size through the promotion of bradykinin (BK) stability. Although CMF express BK receptors, their activity under the reduced O{sub 2} conditions that occur following infarct are entirely unexplored. Using Fura-2 microfluorimetry on primary human CMF, we found that hypoxia significantly increased the mobilisation of Ca{sup 2+} from intracellular stores in response to BK whilst capacitative Ca{sup 2+} entry (CCE) remained unchanged. The enhanced store mobilisation was due to a striking increase in CMF intracellular Ca{sup 2+}-store content under hypoxic conditions. However, BK-induced CMF migration or proliferation was not affected following hypoxic exposure, suggesting that Ca{sup 2+} influx rather than mobilisation is of primary importance in CMF migration and proliferation.

  7. Time Domains of the Hypoxic Ventilatory Response and Their Molecular Basis.

    Science.gov (United States)

    Pamenter, Mathhew E; Powell, Frank L

    2016-01-01

    Ventilatory responses to hypoxia vary widely depending on the pattern and length of hypoxic exposure. Acute, prolonged, or intermittent hypoxic episodes can increase or decrease breathing for seconds to years, both during the hypoxic stimulus, and also after its removal. These myriad effects are the result of a complicated web of molecular interactions that underlie plasticity in the respiratory control reflex circuits and ultimately control the physiology of breathing in hypoxia. Since the time domains of the physiological hypoxic ventilatory response (HVR) were identified, considerable research effort has gone toward elucidating the underlying molecular mechanisms that mediate these varied responses. This research has begun to describe complicated and plastic interactions in the relay circuits between the peripheral chemoreceptors and the ventilatory control circuits within the central nervous system. Intriguingly, many of these molecular pathways seem to share key components between the different time domains, suggesting that varied physiological HVRs are the result of specific modifications to overlapping pathways. This review highlights what has been discovered regarding the cell and molecular level control of the time domains of the HVR, and highlights key areas where further research is required. Understanding the molecular control of ventilation in hypoxia has important implications for basic physiology and is emerging as an important component of several clinical fields. © 2016 American Physiological Society. Compr Physiol 6:1345-1385, 2016. PMID:27347896

  8. Microbial respiration and extracellular enzyme activity in sediments from the Gulf of Mexico hypoxic zone

    Science.gov (United States)

    This study explores the relationship between sediment chemistry (TC, TN, TP) and microbial respiration (DHA) and extracellular enzyme activity (EEA) across the Gulf of Mexico (GOM) hypoxic zone. TC, TN, and TP were all positively correlated with each other (r=0.19-0.68). DHA was ...

  9. Association of NOS3 gene variants and clinical contributors of hypoxic-ischemic encephalopathy

    Directory of Open Access Journals (Sweden)

    R. Kuzmani? ?amija

    2014-10-01

    Full Text Available The aim of this study was to analyze the association of different clinical contributors of hypoxic-ischemic encephalopathy with NOS3 gene polymorphisms. A total of 110 children with hypoxic-ischemic encephalopathy and 128 control children were selected for this study. Association of gender, gestational age, birth weight, Apgar score, cranial ultrasonography, and magnetic resonance imaging findings with genotypic data of six haplotype-tagging single nucleotide polymorphisms and the most commonly investigated rs1800779 and rs2070744 polymorphisms was analyzed. The TGT haplotype of rs1800783, rs1800779, and rs2070744 polymorphisms was associated with hypoxic-ischemic encephalopathy. Children with the TGT haplotype were infants below 32 weeks of gestation and they had the most severe brain damage. Increased incidence of the TT genotype of the NOS3 rs1808593 SNP was found in the group of hypoxic-ischemic encephalopathy patients with medium and severe brain damage. The probability of brain damage was twice as high in children with the TT genotype than in children with the TG genotype of the same polymorphism. Furthermore, the T allele of the same polymorphism was twice as frequent in children with lower Apgar scores. This study strongly suggests associations of NOS3 gene polymorphism with intensity of brain damage and severity of the clinical picture in affected children.

  10. Impact of hypoxic versus normoxic training on physical fitness and vasculature in diabetes.

    NARCIS (Netherlands)

    Schreuder, T.H.A.; Nyakayiru, J.; Houben, J.; Thijssen, D.H.J.; Hopman, M.T.E.

    2014-01-01

    BACKGROUND: Exercise training improves physical fitness, insulin resistance, and endothelial function in type 2 diabetes. Hypoxia may further optimize these beneficial effects. The aim of this study was to compare the effects of hypoxic versus normoxic exercise training on physical fitness, endothel

  11. Expression of Monocarboxylate Transporter Isoforms in Rat Skeletal Muscle Under Hypoxic Preconditioning and Endurance Training.

    Science.gov (United States)

    Saxena, Saurabh; Shukla, Dhananjay; Bansal, Anju

    2016-03-01

    Previously, we have reported the regulation of monocarboxylate transporters (MCT)1 and MCT4 by physiological stimuli such as hypoxia and exercise. In the present study, we have evaluated the effect of hypoxic preconditioning and training on expression of different MCT isoforms in muscles. We found the increased mRNA expression of MCT1, MCT11, and MCT12 after hypoxic preconditioning with cobalt chloride and training. However, the expression of other MCT isoforms increased marginally or even reduced after hypoxic preconditioning. Only the protein expression of MCT1 increased after hypoxia preconditioning. MCT2 protein expression increased after training only and MCT4 protein expression decreased both in preconditioning and hypoxic training. Furthermore, we found decreased plasma lactate level during hypoxia preconditioning (0.74-fold), exercise (0.78-fold), and hypoxia preconditioning along with exercise (0.67-fold), which indicates increased lactate uptake by skeletal muscle. The protein-protein interactions with hypoxia inducible factor-1 and MCT isoforms were also evaluated, but no interaction was found. In conclusion, we say that almost all MCTs are expressed in red gastrocnemius muscle at the mRNA level and their expression is regulated differently under hypoxia preconditioning and exercise condition. PMID:26716978

  12. Expression of Clock genes in the pineal glands of newborn rats with hypoxic-ischemic encephalopathy

    Institute of Scientific and Technical Information of China (English)

    Bin Sun; Xing Feng; Xin Ding; Li Bao; Yongfu Li; Jun He; Meifang Jin

    2012-01-01

    Clock genes are involved in circadian rhythm regulation,and surviving newborns with hypoxic-ischemic encephalopathy may present with sleep-wake cycle reversal.This study aimed to determine the expression of the clock genes Clock and Bmall,in the pineal gland of rats with hypoxic-ischemic brain damage.Results showed that levels of Clock mRNA were not significantly changed within 48 hours after cerebral hypoxia and ischemia.Expression levels of CLOCK and BMAL1 protein were significantly higher after 48 hours.The levels of Bmall mRNA reached a peak at 36 hours,but were significantly reduced at 48 hours.Experimental findings indicate that Clock and Bmall genes were indeed expressed in the pineal glands of neonatal rats.At the initial stage (within 36 hours) of hypoxic-ischemic brain damage,only slight changes in the expression levels of these two genes were detected,followed by significant changes at 36 48 hours.These changes may be associated with circadian rhythm disorder induced by hypoxic-ischemic brain damage.

  13. Association of NOS3 gene variants and clinical contributors of hypoxic-ischemic encephalopathy

    Energy Technology Data Exchange (ETDEWEB)

    Kuzmanić Šamija, R. [Department of Pediatrics, University Hospital Split, Split (Croatia); Primorac, D. [School of Medicine Split, University of Split, Split (Croatia); Department of Pediatrics, School of Medicine, University of Osijek, Osijek (Croatia); Eberly College of Science, Penn State University, University Park, PA (United States); St. Catherine Speciality Hospital, Zabok (Croatia); Rešić, B. [School of Medicine Split, University of Split, Split (Croatia); Pavlov, V. [Department of Neonatology, University Hospital Split, Split (Croatia); Čapkun, V. [Department of Nuclear Medicine, University Hospital Split, Split (Croatia); Punda, H. [School of Medicine Split, University of Split, Split (Croatia); Lozić, B. [Department of Pediatrics, University Hospital Split, Split (Croatia); Zemunik, T. [Department of Medical Biology, School of Medicine Split, University of Split, Split (Croatia)

    2014-08-15

    The aim of this study was to analyze the association of different clinical contributors of hypoxic-ischemic encephalopathy with NOS3 gene polymorphisms. A total of 110 children with hypoxic-ischemic encephalopathy and 128 control children were selected for this study. Association of gender, gestational age, birth weight, Apgar score, cranial ultrasonography, and magnetic resonance imaging findings with genotypic data of six haplotype-tagging single nucleotide polymorphisms and the most commonly investigated rs1800779 and rs2070744 polymorphisms was analyzed. The TGT haplotype of rs1800783, rs1800779, and rs2070744 polymorphisms was associated with hypoxic-ischemic encephalopathy. Children with the TGT haplotype were infants below 32 weeks of gestation and they had the most severe brain damage. Increased incidence of the TT genotype of the NOS3 rs1808593 SNP was found in the group of hypoxic-ischemic encephalopathy patients with medium and severe brain damage. The probability of brain damage was twice as high in children with the TT genotype than in children with the TG genotype of the same polymorphism. Furthermore, the T allele of the same polymorphism was twice as frequent in children with lower Apgar scores. This study strongly suggests associations of NOS3 gene polymorphism with intensity of brain damage and severity of the clinical picture in affected children.

  14. Does aetiology of neonatal encephalopathy and hypoxic-ischaemic encephalopathy influence the outcome of treatment?

    Science.gov (United States)

    Mcintyre, Sarah; Badawi, Nadia; Blair, Eve; Nelson, Karin B

    2015-04-01

    Neonatal encephalopathy, a clinical syndrome affecting term-born and late preterm newborn infants, increases the risk of perinatal death and long-term neurological morbidity, especially cerebral palsy. With the advent of therapeutic hypothermia, a treatment designed for hypoxic or ischaemic injury, associated mortality and morbidity rates have decreased. Unfortunately, only about one in eight neonates (95% confidence interval) who meet eligibility criteria for therapeutic cooling apparently benefit from the treatment. Studies of infants in representative populations indicate that neonatal encephalopathy is a potential result of a variety of antecedents and that asphyxial complications at birth account for only a small percentage of neonatal encephalopathy. In contrast, clinical case series suggest that a large proportion of neonatal encephalopathy is hypoxic or ischaemic, and trials of therapeutic hypothermia are specifically designed to include only infants exposed to hypoxia or ischaemia. This review addresses the differences, definitional and methodological, between infants studied and investigations undertaken, in population studies compared with cooling trials. It raises the question if there may be subgroups of infants with a clinical diagnosis of hypoxic-ischaemic encephalopathy (HIE) in whom the pathobiology of neonatal neurological depression is not fundamentally hypoxic or ischaemic and, therefore, for whom cooling may not be beneficial. In addition, it suggests approaches to future trials of cooling plus adjuvant therapy that may contribute to further improvement of care for these vulnerable neonates.

  15. Mechanisms of Hypoxic Up-Regulation of Versican Gene Expression in Macrophages.

    Directory of Open Access Journals (Sweden)

    Fattah Sotoodehnejadnematalahi

    Full Text Available Hypoxia is a hallmark of many pathological tissues. Macrophages accumulate in hypoxic sites and up-regulate a range of hypoxia-inducible genes. The matrix proteoglycan versican has been identified as one such gene, but the mechanisms responsible for hypoxic induction are not fully characterised. Here we investigate the up-regulation of versican by hypoxia in primary human monocyte-derived macrophages (HMDM, and, intriguingly, show that versican mRNA is up-regulated much more highly (>600 fold by long term hypoxia (5 days than by 1 day of hypoxia (48 fold. We report that versican mRNA decay rates are not affected by hypoxia, demonstrating that hypoxic induction of versican mRNA is mediated by increased transcription. Deletion analysis of the promoter identified two regions required for high level promoter activity of luciferase reporter constructs in human macrophages. The hypoxia-inducible transcription factor HIF-1 has previously been implicated as a key potential regulator of versican expression in hypoxia, however our data suggest that HIF-1 up-regulation is unlikely to be principally responsible for the high levels of induction observed in HMDM. Treatment of HMDM with two distinct specific inhibitors of Phosphoinositide 3-kinase (PI3K, LY290042 and wortmannin, significantly reduced induction of versican mRNA by hypoxia and provides evidence of a role for PI3K in hypoxic up-regulation of versican expression.

  16. Hypoxic preconditioning induces neuroprotective stanniocalcin-1 in brain via IL-6 signaling

    DEFF Research Database (Denmark)

    Westberg, Johan A; Serlachius, Martina; Lankila, Petri;

    2007-01-01

    mRNA levels in brains of wild-type and IL-6 deficient mice. Furthermore, we monitored the Stc-1 response in brains of wild-type and transgenic mice, overexpressing IL-6 in the astroglia, before and after induced brain injury. RESULTS: Hypoxic preconditioning induced an upregulated expression of Stc...

  17. From top to bottom: the two faces of HIPK2 for regulation of the hypoxic response.

    Science.gov (United States)

    Calzado, Marco A; De La Vega, Laureano; Munoz, Eduardo; Schmitz, M Lienhard

    2009-06-01

    Oxygen deprivation (hypoxia) triggers a complex network of signaling pathways that result in changed gene expression patterns in order to cope with this challenge. Recent work has identified the serine/threonine kinase HIPK2 as a novel regulatory protein participating in hypoxic gene regulation. HIPK2 can affect apical as well as downstream events during the hypoxic response. Under normoxic conditions, HIPK2-mediated phosphorylation of the ubiquitin E3 ligase Siah2 weakens mutual binding and destabilizes the phosphorylated E3 ligase. Low oxygen levels result in strongly increased HIPK2/Siah2 interactions that lead to efficient polyubiquitylation and proteasomal degradation of the kinase. At the apical level, the Siah2 inhibiting phosphorylations are lost, thus allowing Siah2-dependent proteolysis of dioxygenases which in turn allows for activation of transcription factor HIF. Downstream events of the hypoxic response are affected by the proteasomal elimination of HIPK2 from gene repressing complexes, an event that allows for full induction of gene expression. Thus HIPK2 can regulate a subset of HIF-dependent and -independent genes during the hypoxic response.

  18. EEG and MR Spectroscopy in Hypoxic-Ischemic Encephalopathy in Term Newborns

    OpenAIRE

    J Gordon Millichap

    2010-01-01

    Researchers from the University of Bologna, Italy, studied the relation of amplitude integrated EEG findings in the first 24 hrs of life to brain metabolic changes, detected by proton MR spectroscopy (H-MRS) at 7-10 days of life, in 32 term newborns with hypoxic-ischemic encephalopathy (HIE).

  19. Hypoxic treatment inhibits insulin-induced chondrogenesis of ATDC5 cells despite upregulation of DEC1

    DEFF Research Database (Denmark)

    Chen, Li; Fink, Trine; Ebbesen, Peter;

    2006-01-01

    Chondrogenesis occurs in vivo in a hypoxic environment, in which the hypoxia inducible factor 1, HIF-1, plays a regulatory role, possibly mediated through the transcription factor DEC1. We have analyzed the effect of hypoxia (1% oxygen) alone and in combination with insulin on the chondrogenic di...

  20. Acute hypoxic exercise does not alter post-exercise iron metabolism in moderately trained endurance athletes

    NARCIS (Netherlands)

    Govus, A.D.; Abbiss, C.R.; Garvican-Lewis, L.A.; Swinkels, D.W.; Laarakkers, C.M.; Gore, C.J.; Peeling, P.

    2014-01-01

    PURPOSE: This study measured the influence of acute hypoxic exercise on Interleukin-6 (IL-6), hepcidin, and iron biomarkers in athletes. METHODS: In a repeated measures design, 13 moderately trained endurance athletes performed 5 x 4 min intervals at 90 % of their peak oxygen consumption velocity (v

  1. Effect of β3-adrenergic agonists on alveolar fluid clearance in hypoxic rat lungs

    Institute of Scientific and Technical Information of China (English)

    LI Nai-jing; LI Wei; HE Ping; GU Xiu; LI Sheng-qi

    2010-01-01

    Background Recent research suggests that β_2-adrenergic agonists increase alveolar fluid clearance (AFC) under physiologic and pathologic conditions. It is unknown whether β_3-adrenergic agonists also increase AFC under pathologic conditions. The aim of this study was to investigate the effect of β_3 -adrenergic agonists on AFC following hypoxic lung injury and the mechanisms involved.Methods Hypoxic rats were exposed to 10% oxygen. BRL-37344 (β_3-adrenergic agonist) or CGP-12177 (selective β_3-adrenergic agonist) alone or combined with β receptor antagonists, sodium channel blockers, or Na~+/K~+-ATPase blockers were perfused into the alveolar space of rats exposed to 10% oxygen for 48 hours. Total lung water content (TLW) and AFC were measured.Results AFC did not change for the first 24 hours but then decreased after 48-hour exposure to 10% oxygen. The perfusion of BRL-37344 or CGP-12177 significantly increased AFC in normal and hypoxic rats. The AFC-stimulating effect of CGP-12177 was lowered with amiloride (a Na~+ channel blocker) and ouabain (a Na~+/K~+-ATPase inhibitor) by 37% and 49%, respectively. Colchicine significantly inhibited the effect of CGP-12177.Conclusions These findings suggest that (β3-adrenergic agonists can increase AFC during hypoxic lung injury in rats and accelerate the amelioration of pulmonary edema.

  2. Extreme hypoxic conditions induce selective molecular responses and metabolic reset in detached apple fruit

    Directory of Open Access Journals (Sweden)

    Dubravka eCukrov

    2016-02-01

    Full Text Available The ripening physiology of detached fruit is altered by low oxygen conditions with profound effects on quality parameters. To study hypoxia-related processes and regulatory mechanisms, apple (Malus domestica, cv Granny Smith fruit, harvested at commercial ripening, were kept at 1°C under normoxic (control and hypoxic (0.4 and 0.8 kPa oxygen conditions for up to 60 days. NMR analyses of cortex tissue identified eight metabolites showing significantly different accumulations between samples, with ethanol and alanine displaying the most pronounced difference between hypoxic and normoxic treatments A rapid up-regulation of alcohol dehydrogenase and pyruvate-related metabolism (lactate dehydrogenase, pyruvate decarboxylase, alanine aminotransferase gene expression was detected under both hypoxic conditions with a more pronounced effect induced by the lowest (0.4 kPa oxygen concentration. Both hypoxic conditions negatively affected ACC synthase and ACC oxidase transcript accumulation. Analysis of RNA-seq data of samples collected after 24 days of hypoxic treatment identified more than 1,000 genes differentially expressed when comparing 0.4 vs 0.8 kPa oxygen concentration samples. Genes involved in cell-wall, minor and major CHO, amino acid and secondary metabolisms, fermentation and glycolysis as well as genes involved in transport, defense responses and oxidation-reduction appeared to be selectively affected by treatments. The lowest oxygen concentration induced a higher expression of transcription factors belonging to AUX/IAA, WRKY, HB, Zinc-finger families, while MADS box family genes were more expressed when apples were kept under 0.8 kPa oxygen. Out of the eight group VII ERF members present in apple genome, two genes showed a rapid up-regulation under hypoxia, and western blot analysis showed that apple MdRAP2.12 proteins were differentially accumulated in normoxic and hypoxic samples, with the highest level reached under 0.4 kPa oxygen. These

  3. IMD-4690, a Novel Specific Inhibitor for Plasminogen Activator Inhibitor-1, Reduces Allergic Airway Remodeling in a Mouse Model of Chronic Asthma via Regulating Angiogenesis and Remodeling-Related Mediators

    OpenAIRE

    Tezuka, Toshifumi; Ogawa, Hirohisa; AZUMA, MASAHIKO; GOTO, HISATSUGU; Uehara, Hisanori; Aono, Yoshinori; Hanibuchi, Masaki; Yamaguchi, Yoichi; Fujikawa, Tomoyuki; Itai, Akiko; Nishioka, Yasuhiko

    2015-01-01

    Plasminogen activator inhibitor (PAI)-1 is the principal inhibitor of plasminogen activators, and is responsible for the degradation of fibrin and extracellular matrix. IMD-4690 is a newly synthesized inhibitor for PAI-1, whereas the effect on allergic airway inflammation and remodeling is still unclear. We examined the in vivo effects by using a chronic allergen exposure model of bronchial asthma in mice. The model was generated by an immune challenge for 8 weeks with house dust mite antigen...

  4. Cytosine Deaminase/5-Fluorocytosine Exposure Induces Bystander and Radiosensitization Effects in Hypoxic Glioblastoma Cells in vitro

    International Nuclear Information System (INIS)

    Purpose: Treatment of glioblastoma (GBM) is limited by therapeutic ratio; therefore, successful therapy must be specifically cytotoxic to cancer cells. Hypoxic cells are ubiquitous in GBM, and resistant to radiation and chemotherapy, and, thus, are logical targets for gene therapy. In this study, we investigated whether cytosine deaminase (CD)/5-fluorocytosine (5-FC) enzyme/prodrug treatment induced a bystander effect (BE) and/or radiosensitization in hypoxic GBM cells. Methods and Materials: We stably transfected cells with a gene construct consisting of the SV40 minimal promoter, nine copies of a hypoxia-responsive element, and the yeast CD gene. During hypoxia, a hypoxia-responsive element regulates expression of the CD gene and facilitates the conversion of 5-FC to 5-fluorouracil, a highly toxic antimetabolite. We used colony-forming efficiency (CFE) and immunofluorescence assays to assess for BE in co-cultures of CD-expressing clone cells and parent, pNeo- or green fluorescent protein-stably transfected GBM cells. We also investigated the radiosensitivity of CD clone cells treated with 5-FC under hypoxic conditions, and we used flow cytometry to investigate treatment-induced cell cycle changes. Results: Both a large BE and radiosensitization occurred in GBM cells under hypoxic conditions. The magnitude of the BE depended on the number of transfected cells producing CD, the functionality of the CD, the administered concentration of 5-FC, and the sensitivity of cell type to 5-fluorouracil. Conclusion: Hypoxia-inducible CD/5-FC therapy in combination with radiation therapy shows both a pronounced BE and a radiosensitizing effect under hypoxic conditions

  5. Evidence of hypoxic foraging forays by yellow perch (Perca flavescens) and potential consequences for prey consumption

    Science.gov (United States)

    Roberts, James J.; Grecay, Paul A.; Ludsin, Stuart A.; Pothoven, Steve A.; Vanderploeg, Henry A.; Höök, Tomas O.

    2012-01-01

    Previous studies in a variety of ecosystems have shown that ecologically and economically important benthic and bentho-pelagic fishes avoid hypoxic (−1) habitats by moving vertically or horizontally to more oxygenated areas. While avoidance of hypoxic conditions generally leads to a complete shift away from preferred benthic prey, some individual fish continue to consume benthic prey items in spite of bottom hypoxia, suggesting complex habitat utilisation and foraging patterns. For example, Lake Erie yellow perch (Perca flavescens) continue to consume benthic prey, despite being displaced vertically and horizontally by hypolimnetic hypoxia. We hypothesised that hypolimnetic hypoxia can negatively affect yellow perch by altering their distribution and inducing energetically expensive foraging behaviour. To test this hypothesis, we used drifting hydroacoustics and trawl sampling to quantify water column distribution, sub-daily vertical movement and foraging behaviour of yellow perch within hypoxic and normoxic habitats of Lake Erie’s central basin during August-September 2007. We also investigated the effects of rapid changes in ambient oxygen conditions on yellow perch consumption potential by exposing yellow perch to various static and fluctuating oxygen conditions in a controlled laboratory experiment. Our results indicate that, while yellow perch in general avoid hypoxic conditions, some individuals undertake foraging forays into hypoxic habitats where they experience greater fluctuations in abiotic conditions (pressure, temperature and oxygen concentration) than at normoxic sites. However, laboratory results suggest short-term exposure to low oxygen conditions did not negatively impact consumption potential of yellow perch. Detailed understanding of sub-daily individual behaviours may be crucial for determining interactive individual- and ecosystem-level effects of stressors such as hypoxia.

  6. Scintigraphic imaging of focal hypoxic tissue: development and clinical applications of {sup 123} I-IAZA

    Energy Technology Data Exchange (ETDEWEB)

    Wiebe, Leonard I.; McEwan, Alexander J.B. [Alberta Univ., Edmonton (Canada); Cross Cancer Institute, Edmonton (Canada); E-mail: leonard.wiebe@ualberta.ca

    2002-09-01

    Affected tissues in a number of diseases, including cancer, stroke, cardiac infarction and diabetes, develop focal tissue hypoxia during their progression. Tbe presence of hypoxic tissue may make the disease refractory to therapy, as in the case of solid tumor therapy using low LET ionizing radiation. In other pathologies, the detection of viable but hypoxic tissues may serve as a prodromal indicator of developing disease (e.g. diabetes), or as a prognostic indicator for management of the disease (e.g. stroke). Over the past two decades a number of hypoxia radio imaging agents have been developed and tested clinically. Of these, {sup 18} F-Fm iso and {sup 123} I - IAZA are the most widely used radiotracers for PET and SPECT/planar imaging, respectively. IAZA and Fm iso are a 2-nitroimidazoles that chemically bind to subcellular components of viable hypoxic tissues. They sensitize hypoxic tumor to the killing effects of ionizing radiation via mechanisms that mimic the radiosensitizing effects of oxygen, and are therefore called oxygen mimetic. The oxygen mimetic effect is attributable in large part to the covalent binding of reductively-activated nitroimidazole intermediates to critical cellular macromolecules. Nitroimidazoles labelled with gamma-emitting radionuclides (e.g. {sup 18} F-Fm iso and {sup 123} I -IAZA) have been used as scintigraphic markers of tumour hypoxia, based on the need to identify radioresistant hypoxic tumour cells as part of the radiotherapy planning process. Broader interest in non-invasive, imaging-based identification of focal hypoxia in a number of diseases has extended hypoxia studies to include peripheral vascular disease associated with diabetes, rheumatoid arthritis, stroke, myocardial ischaemia, brain trauma and oxidative stress. In this review, the current status of hypoxia-selective studies with {sup 123} I - IAZA, an experimental diagnostic radiopharmaceutical, is reviewed with respect to its pre-clinical development and clinical

  7. Scintigraphic imaging of focal hypoxic tissue: development and clinical applications of 123 I-IAZA

    International Nuclear Information System (INIS)

    Affected tissues in a number of diseases, including cancer, stroke, cardiac infarction and diabetes, develop focal tissue hypoxia during their progression. Tbe presence of hypoxic tissue may make the disease refractory to therapy, as in the case of solid tumor therapy using low LET ionizing radiation. In other pathologies, the detection of viable but hypoxic tissues may serve as a prodromal indicator of developing disease (e.g. diabetes), or as a prognostic indicator for management of the disease (e.g. stroke). Over the past two decades a number of hypoxia radio imaging agents have been developed and tested clinically. Of these, 18 F-Fm iso and 123 I - IAZA are the most widely used radiotracers for PET and SPECT/planar imaging, respectively. IAZA and Fm iso are a 2-nitroimidazoles that chemically bind to subcellular components of viable hypoxic tissues. They sensitize hypoxic tumor to the killing effects of ionizing radiation via mechanisms that mimic the radiosensitizing effects of oxygen, and are therefore called oxygen mimetic. The oxygen mimetic effect is attributable in large part to the covalent binding of reductively-activated nitroimidazole intermediates to critical cellular macromolecules. Nitroimidazoles labelled with gamma-emitting radionuclides (e.g. 18 F-Fm iso and 123 I -IAZA) have been used as scintigraphic markers of tumour hypoxia, based on the need to identify radioresistant hypoxic tumour cells as part of the radiotherapy planning process. Broader interest in non-invasive, imaging-based identification of focal hypoxia in a number of diseases has extended hypoxia studies to include peripheral vascular disease associated with diabetes, rheumatoid arthritis, stroke, myocardial ischaemia, brain trauma and oxidative stress. In this review, the current status of hypoxia-selective studies with 123 I - IAZA, an experimental diagnostic radiopharmaceutical, is reviewed with respect to its pre-clinical development and clinical applications. (author)

  8. Glaucoma-induced degeneration of retinal ganglion cells prevented by hypoxic preconditioning: a model of glaucoma tolerance.

    Science.gov (United States)

    Zhu, Yanli; Zhang, Lihong; Schmidt, Jimena F; Gidday, Jeffrey M

    2012-01-01

    Like all cells, neurons adapt to stress by transient alterations in phenotype, an epigenetic response that forms the basis for preconditioning against acute ischemic injury in the central nervous system. We recently showed that a modified repetitive hypoxic preconditioning (RHP) regimen significantly extends the window of ischemic tolerance to acute retinal ischemic injury from days to months. The present study was undertaken to determine if this uniquely protracted neuroprotective phenotype would also confer resistance to glaucomatous neurodegeneration. Retinal ganglion cell death at somatic and axonal levels was assessed after both 3 and 10 wks of sustained intraocular hypertension in an adult mouse model of inducible, open-angle glaucoma, with or without RHP before intraocular pressure elevation. Loss of brn3-positive ganglion cell soma after 3 wks of experimental glaucoma, along with increases in several apoptotic endpoints, were all significantly and robustly attenuated in mice subjected to RHP. Soma protection by RHP was also confirmed after 10 wks of intraocular hypertension by brn3 and SMI32 immunostaining. In addition, quantification of axon density in the postlaminar optic nerve documented robust preservation in RHP-treated mice, and neurofilament immunostaining also revealed preconditioning-induced improvements in axon integrity/survival in both retina and optic nerve after 10 wks of experimental glaucoma. This uniquely protracted period of phenotypic change, established in retinal ganglion cells by the activation of latent antiapoptotic, prosurvival mechanisms at both somatic and axonal levels, reflects a novel form of inducible neuronal plasticity that may provide innovative therapeutic targets for preventing and treating glaucoma and other neurodegenerative diseases. PMID:22396016

  9. Establishment of chronic ocular hypertension model by anterior chamber injection of polystyrene microspheres in mouse%前房注射聚苯乙烯微球诱导小鼠慢性高眼压研究

    Institute of Scientific and Technical Information of China (English)

    沈策英; 陈兰兰; 姜利斌

    2014-01-01

    injection of polystyrene,corneal edema was found under the slit lamp microscope,and under the optical microscope,microspheres accumulated at the anterior chamber angle.Additionally,in 2 and 4 weeks after injection,the number of survival RGCs was (4 542.82 ± 653.72)/mm2 and (3 623.12 ± 628.79)/mm2,respectively in the microspheres group,which showed significantly decrease in comparison with (6 979.33 ± 678.49)/mm2 and (6963.91 ±497.29)/mm2 in the normal control group (t =17.729,28.569,both at P<0.05) and (6 843.21 ±573.42)/mm2 and (6 937.53±465.24)/mm2in the PBS group (t =16.975,29.145,both at P<0.05).The number of RGCs was significantly less in the fourth week compared with second week after injection (t =6.951,P<0.05).The β-Ⅲ-tubulin positive RGCs were (4 576.36± 479.64)/mm2 and (3 712.90 ± 660.31)/mm2 in 2 and 4 weeks in the microspheres group,respectively,which were significantly decreased in comparison with (6 725.94 ± 619.42)/mm2 and (6 741.90±663.60)/mm2 of the normal control group (t =18.811,22.182,both at P < 0.05) or (6 757.85 ±463.59)/mm2 and (6 773.17± 471.35)/mm2 in the PBS group (t =18.953,22.605,both at P<0.05),and in the microspheres group,β-Ⅲ-tubulin positive cells in the fourth week were decreased than those in the second week after injection (t=7.253,P<0.05).The neural fiber density in the microspheres group in 2 and 4 weeks after injection was (193.08 ±32.75)/mm2 and (139.O0 ±38.24)/mm2,respectively,with a significant decline in comparison with (305.57±81.21)/mm2 and (297.46±52.60)/mm2(t=8.900,16.883,both at P<0.05) of the normal control group or (312.63±70.62)/mm2 and (269.37±61.63)/mm2 of the PBS group (t=7.731,15.959,both at P<0.05),and the neural fiber density was significantly lower in the fourth week than that in the second week after injection (t =7.442,P<0.05).Conclusions Single injection of polystyrene microspheres into the anterior chamber can induce chronic ocular hypertension in mouse,which leads to the

  10. Hypoxic stress up-regulates Kir2.1 expression and facilitates cell proliferation in brain capillary endothelial cells.

    Science.gov (United States)

    Yamamura, Hideto; Suzuki, Yoshiaki; Yamamura, Hisao; Asai, Kiyofumi; Imaizumi, Yuji

    2016-08-01

    The blood-brain barrier (BBB) is mainly composed of brain capillary endothelial cells (BCECs), astrocytes and pericytes. Brain ischemia causes hypoxic encephalopathy and damages BBB. However, it remains still unclear how hypoxia affects BCECs. In the present study, t-BBEC117 cells, an immortalized bovine brain endothelial cell line, were cultured under hypoxic conditions at 4-5% oxygen for 72 h. This hypoxic stress caused hyperpolarization of resting membrane potential. Patch-clamp recordings revealed a marked increase in Ba(2+)-sensitive inward rectifier K(+) current in t-BBEC117 cells after hypoxic culture. Western blot and real-time PCR analyses showed that Kir2.1 expression was significantly up-regulated at protein level but not at mRNA level after the hypoxic culture. Ca(2+) imaging study revealed that the hypoxic stress enhanced store-operated Ca(2+) (SOC) entry, which was significantly reduced in the presence of 100 μM Ba(2+). On the other hand, the expression of SOC channels such as Orai1, Orai2, and transient receptor potential channels was not affected by hypoxic stress. MTT assay showed that the hypoxic stress significantly enhanced t-BBEC117 cell proliferation, which was inhibited by approximately 60% in the presence of 100 μM Ba(2+). We first show here that moderate cellular stress by cultivation under hypoxic conditions hyperpolarizes membrane potential via the up-regulation of functional Kir2.1 expression and presumably enhances Ca(2+) entry, resulting in the facilitation of BCEC proliferation. These findings suggest potential roles of Kir2.1 expression in functional changes of BCECs in BBB following ischemia. PMID:27235552

  11. Astrocyte-derived proinflammatory cytokines induce hypomyelination in the periventricular white matter in the hypoxic neonatal brain.

    Directory of Open Access Journals (Sweden)

    Yiyu Deng

    Full Text Available Hypoxic exposure in the perinatal period causes periventricular white matter damage (PWMD, a condition associated with myelination abnormalities. Under hypoxic conditions, glial cells were activated and released a large number of inflammatory mediators in the PWM in neonatal brain, which may result in oligodendrocyte (OL loss and axonal injury. This study aims to determine if astrocytes are activated and generate proinflammatory cytokines that may be coupled with the oligodendroglial loss and hypomyelination observed in hypoxic PWMD. Twenty-four 1-day-old Wistar rats were exposed to hypoxia for 2 h. The rats were then allowed to recover under normoxic conditions for 7 or 28 days before being killed. Another group of 24 rats kept outside the chamber was used as age-matched controls. Upregulated expression of TNF-α and IL-1β was observed in astrocytes in the PWM of P7 hypoxic rats by double immunofluorescence, western blotting and real time RT-PCR. This was linked to apoptosis and enhanced expression of TNF-R1 and IL-1R1 in APC(+ OLs. PLP expression was decreased significantly in the PWM of P28d hypoxic rats. The proportion of myelinated axons was markedly reduced by electron microscopy (EM and the average g-ratios were higher in P28d hypoxic rats. Upregulated expression of TNF-α and IL-1β in primary cultured astrocytes as well as their corresponding receptors in primary culture APC(+ oligodendrocytes were detected under hypoxic conditions. Our results suggest that following a hypoxic insult, astrocytes in the PWM of neonatal rats produce inflammatory cytokines such as TNF-α and IL-1β, which induce apoptosis of OLs via their corresponding receptors associated with them. This results in hypomyelination in the PWM of hypoxic rats.

  12. Chimeric elk/mouse prion proteins in transgenic mice

    OpenAIRE

    Tamguney, G; Giles, K; Oehler, A.; Johnson, NL; DeArmond, SJ; Prusiner, SB

    2013-01-01

    Chronic wasting disease (CWD) of deer and elk is a highly communicable neurodegenerative disorder caused by prions. Investigations of CWD are hampered by slow bioassays in transgenic (Tg) mice. Towards the development of Tg mice that will be more susceptible to CWD prions, we created a series of chimeric elk/mouse transgenes that encode the N terminus of elk PrP (ElkPrP) up to residue Y168 and the C terminus of mouse PrP (MoPrP) beyond residue 169 (mouse numbering), designated Elk3M(SNIVVK). ...

  13. [Chronicity, chronicization, systematization of delusions].

    Science.gov (United States)

    Trapet, P; Fernandez, C; Galtier, M C; Gisselmann, A

    1984-05-01

    Chronicity in psychopathology is indicative of a term, a decay. Chronicization only leads the way to this term. Here, chronicization is taken literally as an inscription in the time course of delusions. The mechanism of systematization seems to be a central mark in the approach to chronic delusions. It is not an alienation or an irreversible closing but an attempted accommodation with reality in the life of psychotic subjects, irrespective of the delusional structure. The role of therapy and drug treatment as a follow-up may in that case assume another meaning.

  14. Dinitrobenzamide mustard prodrugs - hypoxic cytotoxins and dual substrates for E.coli nitroreductase

    International Nuclear Information System (INIS)

    Conditional replicating adenoviral vectors (CRAds) have received considerable attention as therapeutic tools in combination with radiotherapy. Viral distribution and micro-regional geometry are likely to be important issues in the treatment of human solid tumours with gene therapy, particularly following intravenous virus administration. The use of CRAds that are 'armed' with enzyme/prodrug systems may overcome some of the perceived limitations; CRAds can redistribute and self-amplify in a cytolytic fashion whilst prodrug metabolites may elicit a local bystander effect. Either or both of these cytotoxic properties could have favourable interactions with radiotherapy (IR). Nevertheless, they may be insufficient to avoid pockets of vector-naive tumour cells beyond the diffusion limits of cytotoxic prodrug metabolites, such as when perivascular seeding occurs. Under such circumstances hypoxic tumour cells may represent the least accessible compartment for vector transfection; the same tumour subpopulation that is likely to be radioresistant. E.coli nitroreductase (NTR) can bioactivate dinitrobenzamide mustards (DNBMs) and is a promising enzyme/prodrug system for 'arming' CRAds. Notably DNMBs can also be activated by endogenous human reductases under low oxygen conditions providing an opportunity to identify dual hypoxic cytotoxins/NTR substrates that may circumvent some of the geometry issues and provide complementarity with IR. To identify a prodrug for NTR that is also active as a hypoxic cytotoxin in vivo. From a set of 164 DNB prodrugs, 19 with favourable activity in vitro against a panel of four NTR-expressing cancer cells were selected and screened for activity as hypoxic cytotoxins in vitro. Measured E17 values ranged from -444 to -366 mV. Seven DNBMs possessed acceptable hypoxic selectivity against the human NSCLC cell line A549WT or clones engineered to overexpress either a human single-electron reductase, cytochrome P450 reductase (A549P450R), or oxic

  15. AMP-Activated Protein Kinase Is Essential for Survival in Chronic Hypoxia

    OpenAIRE

    Borger, Darrell R.; Gavrilescu, L. Cristina; Bucur, Maria C.; Ivan, Mircea; DeCaprio, James A.

    2008-01-01

    This study was undertaken to interrogate cancer cell survival during long-term hypoxic stress. Two systems with relevance to carcinogenesis were employed: fully transformed BJ cells, and a renal carcinoma cell line (786-0). The dynamic of AMPK activity was consistent with a prosurvival role during chronic hypoxia. This was further supported by the effects of AMPK agonists and antagonists (AICAR and Compound C). Expression of a dominant-negative AMPK alpha resulted in decreased ATP level, and ...

  16. Dormancy of Cancer Cells with Suppression of AKT Activity Contributes to Survival in Chronic Hypoxia

    OpenAIRE

    Hiroko Endo; Hiroaki Okuyama; Masayuki Ohue; Masahiro Inoue

    2014-01-01

    A hypoxic microenvironment in tumors has been recognized as a cause of malignancy or resistance to various cancer therapies. In contrast to recent progress in understanding the acute response of cancer cells to hypoxia, the characteristics of tumor cells in chronic hypoxia remain elusive. We have identified a pancreatic cancer cell line, AsPC-1, that is exceptionally able to survive for weeks under 1% oxygen conditions while most tested cancer cell lines die after only some days under these c...

  17. Chronic hypoxia inhibits MMP-2 activation and cellular invasion in human cardiac myofibroblasts

    OpenAIRE

    Riches, Kirsten; Morley, Michael E.; Turner, Neil A; O'Regan, David J; Ball, Stephen G; Peers, Chris; Porter, Karen E

    2009-01-01

    Cardiac myofibroblasts are pivotal to adaptive remodelling after myocardial infarction (MI). These normally quiescent cells invade and proliferate as a wound healing response, facilitated by activation of matrix metalloproteinases, particularly MMP-2. Following MI these reparative events occur under chronically hypoxic conditions yet the mechanisms by which hypoxia might modulate MMP-2 activation and cardiac myofibroblast invasion have not been investigated. Human cardiac myofibroblasts cultu...

  18. 55th Bowditch Lecture: Effects of chronic hypoxia on the pulmonary circulation: Role of HIF-1

    OpenAIRE

    Shimoda, Larissa A.

    2012-01-01

    When exposed to chronic hypoxia (CH), the pulmonary circulation responds with enhanced contraction and vascular remodeling, resulting in elevated pulmonary arterial pressures. Our work has identified CH-induced alterations in the expression and activity of several ion channels and transporters in pulmonary vascular smooth muscle that contribute to the development of hypoxic pulmonary hypertension and uncovered a critical role for the transcription factor hypoxia-inducible factor-1 (HIF-1) in ...

  19. Towards a mouse model of depression: a psychoneuroendocrine approach

    OpenAIRE

    Dalm, Sergiu

    2012-01-01

    Chronic stress is considered a vulnerability factor for depression. A key symptom is anhedonia; a reduced response to positive stimuli. Drugs are effective for only 20-40% of the patients and new drugs are urgently needed. The objective of the research was to develop a mouse model of depression that would express anhedonia, induced by chronic stress. Mice were repeatedly exposed to the non-physical presence of a rat. Alterations in stress system activity were measured. Anhedonia was assessed ...

  20. A voxel-based multiscale model to simulate the radiation response of hypoxic tumors

    Energy Technology Data Exchange (ETDEWEB)

    Espinoza, I., E-mail: iespinoza@fis.puc.cl [Institute of Physics, Pontificia Universidad Católica de Chile, Santiago 7820436, Chile and Department of Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Heidelberg 69120 (Germany); Peschke, P. [Clinical Cooperation Unit Molecular Radiooncology, German Cancer Research Center (DKFZ), Heidelberg 69120 (Germany); Karger, C. P. [Department of Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Heidelberg 69120 (Germany)

    2015-01-15

    Purpose: In radiotherapy, it is important to predict the response of tumors to irradiation prior to the treatment. This is especially important for hypoxic tumors, which are known to be highly radioresistant. Mathematical modeling based on the dose distribution, biological parameters, and medical images may help to improve this prediction and to optimize the treatment plan. Methods: A voxel-based multiscale tumor response model for simulating the radiation response of hypoxic tumors was developed. It considers viable and dead tumor cells, capillary and normal cells, as well as the most relevant biological processes such as (i) proliferation of tumor cells, (ii) hypoxia-induced angiogenesis, (iii) spatial exchange of cells leading to tumor growth, (iv) oxygen-dependent cell survival after irradiation, (v) resorption of dead cells, and (vi) spatial exchange of cells leading to tumor shrinkage. Oxygenation is described on a microscopic scale using a previously published tumor oxygenation model, which calculates the oxygen distribution for each voxel using the vascular fraction as the most important input parameter. To demonstrate the capabilities of the model, the dependence of the oxygen distribution on tumor growth and radiation-induced shrinkage is investigated. In addition, the impact of three different reoxygenation processes is compared and tumor control probability (TCP) curves for a squamous cells carcinoma of the head and neck (HNSSC) are simulated under normoxic and hypoxic conditions. Results: The model describes the spatiotemporal behavior of the tumor on three different scales: (i) on the macroscopic scale, it describes tumor growth and shrinkage during radiation treatment, (ii) on a mesoscopic scale, it provides the cell density and vascular fraction for each voxel, and (iii) on the microscopic scale, the oxygen distribution may be obtained in terms of oxygen histograms. With increasing tumor size, the simulated tumors develop a hypoxic core. Within the

  1. Replacing the computer mouse

    OpenAIRE

    Dernoncourt, Franck

    2014-01-01

    In a few months the computer mouse will be half-a-century-old. It is known to have many drawbacks, the main ones being: loss of productivity due to constant switching between keyboard and mouse, and health issues such as RSI. Like the keyboard, it is an unnatural human-computer interface. However the vast majority of computer users still use computer mice nowadays. In this article, we explore computer mouse alternatives. Our research shows that moving the mouse cursor can be done efficiently ...

  2. Bidirectional signalling between EphA2 and ephrinA1 increases tubular cell attachment, laminin secretion and modulates erythropoietin expression after renal hypoxic injury.

    Science.gov (United States)

    Rodriguez, Stéphane; Rudloff, Stefan; Koenig, Katrin Franziska; Karthik, Swapna; Hoogewijs, David; Huynh-Do, Uyen

    2016-08-01

    Acute kidney injury (AKI) is common in hospitalized patients and has a poor prognosis, the severity of AKI being linked to progression to chronic kidney disease. This stresses the need to search for protective mechanisms during the acute phase. We investigated kidney repair after hypoxic injury using a rat model of renal artery branch ligation, which led to an oxygen gradient vertical to the corticomedullary axis. Three distinct zones were observed: tubular necrosis, infarction border zone and preserved normal tissue. EphA2 is a receptor tyrosine kinase with pivotal roles in cell architecture, migration and survival, upon juxtacrine contact with its membrane-bound ligand EphrinA1. Following hypoxia, EphA2 was up-regulated in cortical and medullary tubular cells, while EphrinA1 was up-regulated in interstitial cells adjacent to peritubular capillaries. Moreover, erythropoietin (EPO) messenger RNA (mRNA) was strongly expressed in the border zone of infarcted kidney within the first 6 h. To gain more insight into the biological impact of EphA2 and EphrinA1 up-regulation, we activated the signalling pathways in vitro using recombinant EphrinA1/Fc or EphA2/Fc proteins. Stimulation of EphA2 forward signalling in the proximal tubular cell line HK2 increased cell attachment and laminin secretion at the baso-lateral side. Conversely, activation of reverse signalling through EphrinA1 expressed by Hep3B cells promoted EPO production at both the transcriptional and protein level. Strikingly, in co-culture experiments, juxtacrine contact between EphA2 expressing MDCK and EphrinA1 expressing Hep3B was sufficient to induce a significant up-regulation of EPO mRNA production in the latter cells, even in the absence of hypoxic conditions. The synergistic effects of EphA2 and hypoxia led to a 15-20-fold increase of EPO expression. Collectively, our results suggest an important role of EphA2/EphrinA1 signalling in kidney repair after hypoxic injury through stimulation of (i) tubular

  3. An encyclopedia of mouse DNA elements (Mouse ENCODE)

    OpenAIRE

    Stamatoyannopoulos, John A; Guig?? Serra, Roderic; Djebali, Sarah; Lagarde, Julien; Adams, Leslie B.

    2012-01-01

    To complement the human Encyclopedia of DNA Elements (ENCODE) project and to enable a broad range of mouse genomics efforts, the Mouse ENCODE Consortium is applying the same experimental pipelines developed for human ENCODE to annotate the mouse genome.

  4. An encyclopedia of mouse DNA elements (Mouse ENCODE).

    Science.gov (United States)

    Stamatoyannopoulos, John A; Snyder, Michael; Hardison, Ross; Ren, Bing; Gingeras, Thomas; Gilbert, David M; Groudine, Mark; Bender, Michael; Kaul, Rajinder; Canfield, Theresa; Giste, Erica; Johnson, Audra; Zhang, Mia; Balasundaram, Gayathri; Byron, Rachel; Roach, Vaughan; Sabo, Peter J; Sandstrom, Richard; Stehling, A Sandra; Thurman, Robert E; Weissman, Sherman M; Cayting, Philip; Hariharan, Manoj; Lian, Jin; Cheng, Yong; Landt, Stephen G; Ma, Zhihai; Wold, Barbara J; Dekker, Job; Crawford, Gregory E; Keller, Cheryl A; Wu, Weisheng; Morrissey, Christopher; Kumar, Swathi A; Mishra, Tejaswini; Jain, Deepti; Byrska-Bishop, Marta; Blankenberg, Daniel; Lajoie, Bryan R; Jain, Gaurav; Sanyal, Amartya; Chen, Kaun-Bei; Denas, Olgert; Taylor, James; Blobel, Gerd A; Weiss, Mitchell J; Pimkin, Max; Deng, Wulan; Marinov, Georgi K; Williams, Brian A; Fisher-Aylor, Katherine I; Desalvo, Gilberto; Kiralusha, Anthony; Trout, Diane; Amrhein, Henry; Mortazavi, Ali; Edsall, Lee; McCleary, David; Kuan, Samantha; Shen, Yin; Yue, Feng; Ye, Zhen; Davis, Carrie A; Zaleski, Chris; Jha, Sonali; Xue, Chenghai; Dobin, Alex; Lin, Wei; Fastuca, Meagan; Wang, Huaien; Guigo, Roderic; Djebali, Sarah; Lagarde, Julien; Ryba, Tyrone; Sasaki, Takayo; Malladi, Venkat S; Cline, Melissa S; Kirkup, Vanessa M; Learned, Katrina; Rosenbloom, Kate R; Kent, W James; Feingold, Elise A; Good, Peter J; Pazin, Michael; Lowdon, Rebecca F; Adams, Leslie B

    2012-08-13

    To complement the human Encyclopedia of DNA Elements (ENCODE) project and to enable a broad range of mouse genomics efforts, the Mouse ENCODE Consortium is applying the same experimental pipelines developed for human ENCODE to annotate the mouse genome.

  5. 32P uptake and transport to shoots in Pinus serotina seedlings under aerobic and hypoxic growth conditions

    International Nuclear Information System (INIS)

    We examined the effects of long-term hypoxic growth conditions on net uptake and transport of P to shoots of pond pine (Pinus serotina Michx.), a moderately flood-tolerant southern pine. Seedlings were grown under aerobic or hypoxic solution conditions for 4-5 weeks in continuously flowing solution culture containing 100 muM P. Short- and long-term P-32 experiments were then conducted with intact seedlings to determine rates of P-32 influx, efflux and net transport to the shoot. Shoot fresh weight/root fresh weight ratios were significantly higher under hypoxic growth conditions, reflecting the larger reduction in root growth than shoot growth, despite extensive aerechyma formation in roots. Estimates for the unidirectional influx of P-32 in aerobic and hypoxic seedlings were 1.43 and 3.20 mumol P (g(FW) root)-1 h-1, respectively. However, P-32 accumulation between the two treatments became similar within 8 h, suggesting that efflux was also higher in seedlings from the hypoxic treatment. Indeed, in a separate experiment, hypoxic growth conditions increased efflux by over 60%. Transport of P-32 to shoots was significantly reduced under hypoxic growth conditions. despite higher root P concentrations and lower shoot P concentrations. After 48 h, P-32 accumulation in roots was similar between the two treatments, yet total accumulation of seedling P-32 decreased by 31% under the hypoxic treatment, largely because of reduced transport of P-32 to the shoot. The lower accumulation of P-32 by shoots of seedlings in the hypoxic treatment may be the result of a direct inhibition on the transport process in O2-deficient tissues, but could also reflect a slower turnover or labeling of the pool available for transport. Indeed, the percentage of total P-32 in roots present in the soluble P(i) (or transportable form of P) was about 33% lower in seedlings from the hypoxic treatment, probably reflecting increased assimilation into organic compounds as well as chelation with iron

  6. Chronic hypoxia induces the activation of the Wnt/β-catenin signaling pathway and stimulates hippocampal neurogenesis in wild-type and APPswe-PS1ΔE9 transgenic mice in vivo

    Science.gov (United States)

    Varela-Nallar, Lorena; Rojas-Abalos, Macarena; Abbott, Ana C.; Moya, Esteban A.; Iturriaga, Rodrigo; Inestrosa, Nibaldo C.

    2014-01-01

    Hypoxia modulates proliferation and differentiation of cultured embryonic and adult stem cells, an effect that includes β-catenin, a key component of the canonical Wnt signaling pathway. Here we studied the effect of mild hypoxia on the activity of the Wnt/β-catenin signaling pathway in the hippocampus of adult mice in vivo. The hypoxia-inducible transcription factor-1α (HIF-1α) was analyzed as a molecular control of the physiological hypoxic response. Exposure to chronic hypoxia (10% oxygen for 6–72 h) stimulated the activation of the Wnt/β-catenin signaling pathway. Because the Wnt/β-catenin pathway is a positive modulator of adult neurogenesis, we evaluated whether chronic hypoxia was able to stimulate neurogenesis in the subgranular zone (SGZ) of the hippocampal dentate gyrus. Results indicate that hypoxia increased cell proliferation and neurogenesis in adult wild-type mice as determined by Ki67 staining, Bromodeoxyuridine (BrdU) incorporation and double labeling with doublecortin (DCX). Chronic hypoxia also induced neurogenesis in a double transgenic APPswe-PS1ΔE9 mouse model of Alzheimer’s disease (AD), which shows decreased levels of neurogenesis in the SGZ. Our results show for the first time that exposure to hypoxia in vivo can induce the activation of the Wnt/β-catenin signaling cascade in the hippocampus, suggesting that mild hypoxia may have a therapeutic value in neurodegenerative disorders associated with altered Wnt signaling in the brain and also in pathological conditions in which hippocampal neurogenesis is impaired. PMID:24574965

  7. Chronic hypoxia induces the in vivo activation of the Wnt/β-catenin signaling pathway and stimulates hippocampal neurogenesis in wild-type and APPswe-PS1deltaE9 transgenic mice

    Directory of Open Access Journals (Sweden)

    Lorena eVarela-Nallar

    2014-02-01

    Full Text Available Hypoxia modulates proliferation and differentiation of cultured embryonic and adult stem cells, an effect that includes β-catenin a key component of the canonical Wnt signaling pathway. Here we studied in vivo the effect of mild hypoxia on the activity of the Wnt/β-catenin signaling pathway in the hippocampus of adult mice. As a molecular control of the physiological hypoxic response the hypoxia-inducible transcription factor-1α (HIF-1α was analyzed. Exposure to chronic hypoxia (10% oxygen for 6-72 h stimulated the activation of the Wnt/β-catenin signaling pathway. Because the Wnt/β-catenin pathway is a positive modulator of adult neurogenesis, we evaluated whether chronic hypoxia was able to stimulate neurogenesis in the subgranular zone (SGZ of the hippocampal dentate gyrus. Results indicate that hypoxia increased cell proliferation and neurogenesis in adult wild-type mice as determined by Ki67 staining, BrdU incorporation and double labeling with doublecortin. Chronic hypoxia also induced neurogenesis in double transgenic APPswe-PS1deltaE9 mouse model of Alzheimer’s disease (AD, which shows decreased levels of neurogenesis at the SGZ. Our results show for the first time that in vivo exposure to hypoxia can induce the activation of the Wnt/β-catenin signaling cascade in the hippocampus, suggesting that mild hypoxia may have a therapeutic value in neurodegenerative disorder associated with altered Wnt signaling in the brain and also in pathological conditions in which hippocampal neurogenesis is impaired.

  8. Quantifying circulating hypoxia-induced RNA transcripts in maternal blood to determine in utero fetal hypoxic status

    OpenAIRE

    Whitehead, Clare; Teh, Wan Tinn; Walker, Susan P.; Leung, Cheryl; Mendis, Sonali; Larmour, Luke; Tong, Stephen

    2013-01-01

    Background Hypoxia in utero can lead to stillbirth and severe perinatal injury. While current prenatal tests can identify fetuses that are hypoxic, none can determine the severity of hypoxia/acidemia. We hypothesized a hypoxic/acidemic fetus would up-regulate and release hypoxia-induced mRNA from the fetoplacental unit into the maternal circulation, where they can be sampled and quantified. Furthermore, we hypothesized the abundance of hypoxia induced mRNA in the maternal circulation would co...

  9. Deficient activation by a human cell strain leads to mitomycin resistance under aerobic but not hypoxic conditions.

    OpenAIRE

    Marshall, R S; Paterson, M. C.; Rauth, A. M.

    1989-01-01

    Two non-transformed human skin fibroblast strains, GM38 and 3437T, were found to be more sensitive to the bioreductive alkylating agents mitomycin C (MMC) and porfiromycin (PM) under hypoxic compared to aerobic conditions. One of these strains, 3437T, was 6-7 times more resistant to these agents under aerobic exposure conditions, but was identical in sensitivity to the normal strain, GM38, under hypoxic conditions. Aerobic 3437T cells demonstrated no increased resistance to cisplatin compared...

  10. Learning-Memory Function and Swimming Capability of Rat and Ergonomic Evaluation Under Hypoxic Condition

    Institute of Scientific and Technical Information of China (English)

    HU Ding-yu; DAI Rong-ji; LI Bo; MAO Jian; GENG Li-na; DENG Yu-lin

    2009-01-01

    Effects of hypoxia on learning-memory function and swimming capability of rat were studied and the ergonomics under hypoxic condition was also evaluated from the biological point of view. Three modes of hypoxia were designed and plots of oxygen concentration versus time for each group in hypoxic environment were produced. Results showed that the effects of hypoxia on learning-memory function and swimming capability were related with the time and strength of hypoxia. It had nothing to do with the individual difference of rat models. 10% O2 long-term intermittent anamorphosis hypoxia could improve the swimming capability of rat model significantly. Stimulating with proper level of hypoxia, carbon dioxide could improve ergonomics in airtight hypoxia environment. Under hypoxia condition, from the ergonomic point of view, 6% O2 is the important threshold and might belong in critical region.

  11. Cerebral water and ion balance remains stable when humans are exposed to acute hypoxic exercise

    DEFF Research Database (Denmark)

    Avnstorp, Magnus B; Rasmussen, Peter; Brassard, Patrice;

    2015-01-01

    both circumstances. No cerebral net exchange of Na(+) or K(+) was evident. Likewise, no significant net-exchange of water over the brain was demonstrated and the arterial and jugular venous hemoglobin concentrations were similar. CONCLUSION: Challenging exercise in hypoxia for 30 min affected muscle......Avnstorp, Magnus B., Peter Rasmussen, Patrice Brassard, Thomas Seifert, Morten Overgaard, Peter Krustrup, Niels H. Secher, and Nikolai B. Nordsborg. Cerebral water and ion balance remains stable when humans are exposed to acute hypoxic exercise. High Alt Med Biol 16:000-000, 2015.-Background...... intense exercise is carried out in hypoxia and monitored the influence of muscle metabolism for changes in arterial variables. METHODS: On two separate days, in random order, 30 min cycling exercise was performed in either hypoxia (10% O2) or normoxia at an intensity that was exhaustive in the hypoxic...

  12. Actualities on molecular pathogenesis and repairing processes of cerebral damage in perinatal hypoxic-ischemic encephalopathy

    Directory of Open Access Journals (Sweden)

    Praticò Andrea D

    2010-09-01

    Full Text Available Abstract Hypoxic-ischemic encephalopathy (HIE is the most important cause of cerebral damage and long-term neurological sequelae in the perinatal period both in term and preterm infant. Hypoxic-ischemic (H-I injuries develop in two phases: the ischemic phase, dominated by necrotic processes, and the reperfusion phase, dominated by apoptotic processes extending beyond ischemic areas. Due to selective ischemic vulnerability, cerebral damage affects gray matter in term newborns and white matter in preterm newborns with the typical neuropathological aspects of laminar cortical necrosis in the former and periventricular leukomalacia in the latter. This article summarises the principal physiopathological and biochemical processes leading to necrosis and/or apoptosis of neuronal and glial cells and reports recent insights into some endogenous and exogenous cellular and molecular mechanisms aimed at repairing H-I cerebral damage.

  13. Lethal or protective effects of prolonged treatment with hypoxic cell sensitizers

    International Nuclear Information System (INIS)

    AK-2123 [N-(2-methoxyethyl)-2-(3-nitro-1-triazolyl)acetamide] is a hypoxic cell radiosensitizer which is currently being tested in several oncology clinics and which has a lower toxicity than misonidazole (MISO) in vivo. The positive experiences reported recently certainly warrant further clinical evaluations. The experimental observations reported so far need further experimental studies to clarify the sensitization mechanism, especially as recent intratumoral strategies used in the clinical administration of the sensitizers can result in a large local concentration of the drug that may persist for a prolonged period of time between and after radiation exposures. Model experiments in vitro using V79 cells were performed with AK-2123 under these conditions. Misonidazole (MISO) and metronidazole (METRO), well known hypoxic cell radiosensitizers, were used for comparison of the effects. Clonogenic survival and induction and repair of DNA damage were used as end-points

  14. Cytotoxicity and DNA crosslinks produced by mitomycin analogs in aerobic and hypoxic EMT6 cells.

    Science.gov (United States)

    Keyes, S R; Loomis, R; DiGiovanna, M P; Pritsos, C A; Rockwell, S; Sartorelli, A C

    1991-01-01

    Several mitomycin antibiotics were evaluated for their capacities to kill EMT6 tumor cells and to produce DNA crosslinks under conditions of oxygenation and hypoxia. The agents examined included mitomycin C, porfiromycin, and the 7-aminomethyl dithioacetal derivative of mitomycin C (BMY-43324), all of which caused greater kill of hypoxic cells than of their oxygenated counterparts; the N,N'-dimethylaminomethylene derivative of mitomycin C (BMY-25282), which was considerably more cytotoxic under oxygenated conditions than in hypoxia; and the N,N'-dimethylaminomethylene derivative of porfiromycin (BL-6783), which was equal in its toxicity to hypoxic and oxygenated cells. All of these agents produced DNA crosslinks in EMT6 cells, as measured by alkaline elution. The number of crosslinks required to produce a given amount of cell kill was similar, regardless of the mitomycin employed or the degree of oxygenation, suggesting that the crosslinking of DNA was a major lesion in the cytodestructive action of the mitomycins. PMID:1760250

  15. The Hypoxic Regulator of Sterol Synthesis Nro1 Is a Nuclear Import Adaptor

    Energy Technology Data Exchange (ETDEWEB)

    T Yeh; C Lee; L Amzel; P Espenshade; M Bianchet

    2011-12-31

    Fission yeast protein Sre1, the homolog of the mammalian sterol regulatory element-binding protein (SREBP), is a hypoxic transcription factor required for sterol homeostasis and low-oxygen growth. Nro1 regulates the stability of the N-terminal transcription factor domain of Sre1 (Sre1N) by inhibiting the action of the prolyl 4-hydroxylase-like Ofd1 in an oxygen-dependent manner. The crystal structure of Nro1 determined at 2.2 {angstrom} resolution shows an all-{alpha}-helical fold that can be divided into two domains: a small N-terminal domain, and a larger C-terminal HEAT-repeat domain. Follow-up studies showed that Nro1 defines a new class of nuclear import adaptor that functions both in Ofd1 nuclear localization and in the oxygen-dependent inhibition of Ofd1 to control the hypoxic response.

  16. Chronic cholecystitis

    Science.gov (United States)

    ... foods may relieve symptoms in people. However, the benefit of a low-fat diet has not been proven. Alternative Names Cholecystitis - chronic Images Cholecystitis, CT scan Cholecystitis, cholangiogram Cholecystolithiasis Gallstones, cholangiogram Cholecystogram References Wang ...

  17. Chronic Meningitis

    Science.gov (United States)

    ... School Lunch Lines FDA Cracks Down on Antibacterial Soaps Health Tip: Schedule a Back-to-School Dental ... the Professional Version Meningitis Introduction to Meningitis Acute Bacterial Meningitis Viral Meningitis Noninfectious Meningitis Recurrent Meningitis Chronic ...

  18. Transrectal ultrasound-integrated spectral optical tomography of hypoxic progression of a regressing tumor in a canine prostate.

    Science.gov (United States)

    Jiang, Z; Piao, D; Bartels, K E; Holyoak, G R; Ritchey, J W; Ownby, C L; Rock, K; Slobodov, G

    2011-12-01

    The objective of this study was to evaluate if transrectal optical tomography implemented at three wavelength bands for spectral detection could monitor changes of the hemoglobin oxygen saturation (StO2) in addition to those of the total hemoglobin concentration ([HbT]) in lesions of a canine prostate, including an induced tumor modeling canine prostate cancer. Near-infrared (NIR) optical tomography was integrated with ultrasound (US) for transrectal imaging. Multi-spectral detection at 705_nm, 785_nm and 808_nm rendered measurements of [HbT] and StO2. Canine transmissible venereal tumor (TVT) cells were injected into the right lobe of a dog's prostate gland, which had a pre-existing cyst in the left lobe. Longitudinal assessments of the prostate were performed weekly over a 63-day duration by NIR imaging concurrent with grey-scale and Doppler US. Ultrasonography revealed a bi-lobular tumor-mass regressing from day-49 to day-63. At day-49 this tumor-mass developed a hypoxic core that became larger and more intense by day-56 and expanded further by day-63. The tumor-mass presented a strong hyper-[HbT] feature on day-56 that was inconsistent with US-visualized blood flow. Histology confirmed two necrotic TVT foci within this tumor-mass. The cyst appeared to have a large anoxic-like interior that was greater in size than its ultrasonographically delineated lesion, and a weak lesional elevation of [HbT]. On day-56, the cyst presented a strong hyper-[HbT] feature consistent with US-resolved blood flow. Histology revealed acute and chronic hemorrhage in the periphery of the cyst. The NIR imaging features of two other TVT nodules and a metastatic lymph node were evaluated retrospectively. Transrectal US-integrated spectral optical tomography seems to enable longitudinal monitoring of intra-lesional oxygenation dynamics in addition to the hemoglobin content of lesions in the canine prostate.

  19. Adenosine receptors in the immature brain : with special reference to their role in hypoxic ischemia

    OpenAIRE

    Ådén, Ulrika

    2001-01-01

    Although the newborn brain tolerates a much longer period of oxygen deprivation and ischemia than does the adult brain, perinatal hypoxic ischemia probably is an important cause of neurological dysfunction, cerebral palsy and epilepsy later in life. Hence it is important to investigate the mechanisms that modulate the extent of perinatal ischernic brain damage. There is good evidence that endogenous adenosine acts as a neuroprotective agent in models of ischemia in the m...

  20. A proteomic view of Caenorhabditis elegans caused by short-term hypoxic stress

    Directory of Open Access Journals (Sweden)

    Wu Yonghong

    2010-09-01

    Full Text Available Abstract Background The nematode Caenorhabditis elegans is both sensitive and tolerant to hypoxic stress, particularly when the evolutionarily conserved hypoxia response pathway HIF-1/EGL-9/VHL is involved. Hypoxia-induced changes in the expression of a number of genes have been analyzed using whole genome microarrays in C. elegans, but the changes at the protein level in response to hypoxic stress still remain unclear. Results Here, we utilized a quantitative proteomic approach to evaluate changes in the expression patterns of proteins during the early response to hypoxia in C. elegans. Two-dimensional difference gel electrophoresis (2D-DIGE was used to compare the proteomic maps of wild type C. elegans strain N2 under a 4-h hypoxia treatment (0.2% oxygen and under normoxia (control. A subsequent analysis by MALDI-TOF-TOF-MS revealed nineteen protein spots that were differentially expressed. Nine of the protein spots were significantly upregulated, and ten were downregulated upon hypoxic stress. Three of the upregulated proteins were involved in cytoskeletal function (LEV-11, MLC-1, ACT-4, while another three upregulated (ATP-2, ATP-5, VHA-8 were ATP synthases functionally related to energy metabolism. Four ribosomal proteins (RPL-7, RPL-8, RPL-21, RPS-8 were downregulated, indicating a decrease in the level of protein translation upon hypoxic stress. The overexpression of tropomyosin (LEV-11 was further validated by Western blot. In addition, the mutant strain of lev-11(x12 also showed a hypoxia-sensitive phenotype in subsequent analyses, confirming the proteomic findings. Conclusions Taken together, our data suggest that altered protein expression, structural protein remodeling, and the reduction of translation might play important roles in the early response to oxygen deprivation in C. elegans, and this information will help broaden our knowledge on the mechanism of hypoxia response.

  1. Early blood glucose profile and neurodevelopmental outcome at two years in neonatal hypoxic-ischaemic encephalopathy

    LENUS (Irish Health Repository)

    Nadeem, Montasser

    2011-02-04

    Abstract Background To examine the blood glucose profile and the relationship between blood glucose levels and neurodevelopmental outcome in term infants with hypoxic-ischaemic encephalopathy. Methods Blood glucose values within 72 hours of birth were collected from 52 term infants with hypoxic-ischaemic encephalopathy. Hypoglycaemia [< 46.8 mg\\/dL (2.6 mmol\\/L)] and hyperglycaemia [> 150 mg\\/dL (8.3 mmol\\/L)] were correlated to neurodevelopmental outcome at 24 months of age. Results Four fifths of the 468 blood samples were in the normoglycaemic range (392\\/468:83.8%). Of the remaining 76 samples, 51.3% were in the hypoglycaemic range and (48.7%) were hyperglycaemic. A quarter of the hypoglycaemic samples (28.2%:11\\/39) and a third of the hyperglycaemic samples (32.4%:12\\/37) were recorded within the first 30 minutes of life. Mean (SD) blood glucose values did not differ between infants with normal and abnormal outcomes [4.89(2.28) mmol\\/L and 5.02(2.35) mmol\\/L, p value = 0.15] respectively. In term infants with hypoxic-ischaemic encephalopathy, early hypoglycaemia (between 0-6 hours of life) was associated with adverse outcome at 24 months of age [OR = 5.8, CI = 1.04-32)]. On multivariate analysis to adjust for grade of HIE this association was not statistically significant. Late hypoglycaemia (6-72 hours of life) was not associated with abnormal outcome [OR = 0.22, CI (0.04-1.14)]. The occurrence of hyperglycaemia was not associated with adverse outcome. Conclusion During the first 72 hours of life, blood glucose profile in infants with hypoxic-ischaemic encephalopathy varies widely despite a management protocol. Early hypoglycaemia (0-6 hours of life) was associated with severe HIE, and thereby; adverse outcome.

  2. TGF-β2 is involved in the preservation of the chondrocyte phenotype under hypoxic conditions.

    Science.gov (United States)

    Das, R; Timur, U T; Edip, S; Haak, E; Wruck, C; Weinans, H; Jahr, H

    2015-03-01

    Culturing chondrocytes under oxygen tension closely resembling their in vivo environment has been shown to have positive effects on matrix synthesis. In redifferentiation of expanded chondrocytes, hypoxia increased collagen type II expression. However, the mechanism by which hypoxia enhances redifferentiation is still unknown. We employed novel bioreactor technology to investigate the role of TGF-β, a growth factor heavily implicated in matrix production, in chondrocytes under hypoxia. Dedifferentiated chondrocytes in alginate were cultured for 48h under hypoxic (1% pO2) or normoxic (20%) conditions, using specialized bioreactor technology. Hypoxia induced gene expression (GDF1-, PHD3, HAS2, VEGF, COX2), chondrocyte markers (SOX9, COL2, COL1, AGC1 and MMP13), as well as components of the TGF-β signaling pathway (TGF-β isoforms, receptors, and downstream effectors) were analyzed by qPCR after 48h. In addition, protein expression of COL2 and TGF-β2 were evaluated. To further elucidate the involvement of the TGF-β2, we used siRNA and ALK5 inhibition. Hypoxic culture showed robust upregulation of hypoxic markers as well as upregulation of SOX9 and COL2 expression. Of all TGF-β isoforms, only TGF-β2 was upregulated under hypoxia on both gene and protein level. In addition, both type I receptors (ALK1 and ALK5) were upregulated under hypoxia, but type II and III receptors were not. TGF-β2 downregulation via siRNA abrogated the hypoxia-induced COL2 expression, as did ALK5 inhibition, giving a strong indication that this pathway is involved in chondrocyte redifferentiation under low oxygen tension. Hypoxic culture is a common approach for cartilage tissue engineering, but its underlying mechanisms are still poorly understood. Here, we show that increased TGF-β2 signaling through ALK5 plays a role in hypoxia-induced redifferentiation of chondrocytes. PMID:25621374

  3. Early blood glucose profile and neurodevelopmental outcome at two years in neonatal hypoxic-ischaemic encephalopathy.

    LENUS (Irish Health Repository)

    Nadeem, Montasser

    2012-01-31

    BACKGROUND: To examine the blood glucose profile and the relationship between blood glucose levels and neurodevelopmental outcome in term infants with hypoxic-ischaemic encephalopathy. METHODS: Blood glucose values within 72 hours of birth were collected from 52 term infants with hypoxic-ischaemic encephalopathy. Hypoglycaemia [< 46.8 mg\\/dL (2.6 mmol\\/L)] and hyperglycaemia [> 150 mg\\/dL (8.3 mmol\\/L)] were correlated to neurodevelopmental outcome at 24 months of age. RESULTS: Four fifths of the 468 blood samples were in the normoglycaemic range (392\\/468:83.8%). Of the remaining 76 samples, 51.3% were in the hypoglycaemic range and (48.7%) were hyperglycaemic. A quarter of the hypoglycaemic samples (28.2%:11\\/39) and a third of the hyperglycaemic samples (32.4%:12\\/37) were recorded within the first 30 minutes of life. Mean (SD) blood glucose values did not differ between infants with normal and abnormal outcomes [4.89(2.28) mmol\\/L and 5.02(2.35) mmol\\/L, p value = 0.15] respectively. In term infants with hypoxic-ischaemic encephalopathy, early hypoglycaemia (between 0-6 hours of life) was associated with adverse outcome at 24 months of age [OR = 5.8, CI = 1.04-32)]. On multivariate analysis to adjust for grade of HIE this association was not statistically significant. Late hypoglycaemia (6-72 hours of life) was not associated with abnormal outcome [OR = 0.22, CI (0.04-1.14)]. The occurrence of hyperglycaemia was not associated with adverse outcome. CONCLUSION: During the first 72 hours of life, blood glucose profile in infants with hypoxic-ischaemic encephalopathy varies widely despite a management protocol. Early hypoglycaemia (0-6 hours of life) was associated with severe HIE, and thereby; adverse outcome.

  4. Prohibition of artificial hypoxic environments in sports: health risks rather than ethics.

    Science.gov (United States)

    Lippi, Giuseppe; Franchini, Massimo; Guidi, Gian Cesare

    2007-12-01

    There is actual debate on a recent position of the World Anti-Doping Agency (WADA), which has cautiously refrained from banning hypoxic tents and intends to monitor their health risk. Regardless of teleological and deontological concepts, we highlight that the health risks inherent to the widespread use of these artificial performance-enhancing devices would make them as unsafe as other forms of blood doping.

  5. Role of Notch Signaling in the Maintenance of Human Mesenchymal Stem Cells Under Hypoxic Conditions

    OpenAIRE

    MORIYAMA, Hiroyuki; Moriyama, Mariko; Isshi, Haruki; Ishihara, Shin; Okura, Hanayuki; Ichinose, Akihiro; Ozawa, Toshiyuki; Matsuyama, Akifumi; Hayakawa, Takao

    2014-01-01

    Human adipose tissue-derived multilineage progenitor cells (hADMPCs) are attractive for cell therapy and tissue engineering because of their multipotency and ease of isolation without serial ethical issues. However, their limited in vitro lifespan in culture systems hinders their therapeutic application. Some somatic stem cells, including hADMPCs, are known to be localized in hypoxic regions; thus, hypoxia may be beneficial for ex vivo culture of these stem cells. These cells exhibit a high l...

  6. Slow breathing and hypoxic challenge: cardiorespiratory consequences and their central neural substrates.

    Directory of Open Access Journals (Sweden)

    Hugo D Critchley

    Full Text Available Controlled slow breathing (at 6/min, a rate frequently adopted during yoga practice can benefit cardiovascular function, including responses to hypoxia. We tested the neural substrates of cardiorespiratory control in humans during volitional controlled breathing and hypoxic challenge using functional magnetic resonance imaging (fMRI. Twenty healthy volunteers were scanned during paced (slow and normal rate breathing and during spontaneous breathing of normoxic and hypoxic (13% inspired O2 air. Cardiovascular and respiratory measures were acquired concurrently, including beat-to-beat blood pressure from a subset of participants (N = 7. Slow breathing was associated with increased tidal ventilatory volume. Induced hypoxia raised heart rate and suppressed heart rate variability. Within the brain, slow breathing activated dorsal pons, periaqueductal grey matter, cerebellum, hypothalamus, thalamus and lateral and anterior insular cortices. Blocks of hypoxia activated mid pons, bilateral amygdalae, anterior insular and occipitotemporal cortices. Interaction between slow breathing and hypoxia was expressed in ventral striatal and frontal polar activity. Across conditions, within brainstem, dorsal medullary and pontine activity correlated with tidal volume and inversely with heart rate. Activity in rostroventral medulla correlated with beat-to-beat blood pressure and heart rate variability. Widespread insula and striatal activity tracked decreases in heart rate, while subregions of insular cortex correlated with momentary increases in tidal volume. Our findings define slow breathing effects on central and cardiovascular responses to hypoxic challenge. They highlight the recruitment of discrete brainstem nuclei to cardiorespiratory control, and the engagement of corticostriatal circuitry in support of physiological responses that accompany breathing regulation during hypoxic challenge.

  7. Tissue remodeling of rat pulmonary arteries in recovery from hypoxic hypertension

    OpenAIRE

    Li, Zhuangjie; Huang, Wei; Jiang, Zong Lai; Gregersen, Hans; Fung, Yuan-Cheng

    2004-01-01

    The reversibility of tissue remodeling is of general interest to medicine. Pulmonary arterial tissue remodeling during hypertension induced by hypoxic breathing is well known, but little has been said about the recovery of the arterial wall when the blood pressure is lowered again. We hypothesize that tissue recovery is a function of the oxygen concentration, blood pressure, location on the vascular tree, and time. We measured the changes of blood pressure, vessel lumen, vessel wall thickness...

  8. Sexually dimorphic outcomes and inflammatory responses in hypoxic-ischemic encephalopathy

    OpenAIRE

    Mirza, Mehwish A; Ritzel, Rodney; Xu, Yan; McCullough, Louise D.; Liu, Fudong

    2015-01-01

    Background Neonatal hypoxic-ischemic encephalopathy (HIE) is an important cause of motor and cognitive impairment in children. Clinically, male infants are more vulnerable to ischemic insults and suffer more long-term deficits than females; however, the mechanisms underlying this sex difference remain elusive. Inflammatory processes initiated by microglial activation are fundamental in the pathophysiology of ischemia. Recent studies report a sexual dimorphism in microglia numbers and expressi...

  9. Ultrasonic Estimation of Mechanical Properties of Pulmonary Arterial Wall Under Normoxic and Hypoxic Conditions

    Science.gov (United States)

    Waters, Kendall R.; Mukdadi, Osama M.

    2005-04-01

    Secondary pediatric pulmonary hypertension is a disease that could benefit from improved ultrasonic diagnostic techniques. We perform high-frequency in vitro ultrasound measurements (25 MHz to 100 MHz) on fresh and fixed pulmonary arterial walls excised from normoxic and hypoxic Long-Evans rat models. Estimates of the elastic stiffness coefficients are determined from measurements of the speed of sound. Preliminary results indicate that hypoxia leads to up to increase of 20 % in stiffening of the pulmonary arterial wall.

  10. Flow-mediated dilation in the inactive limb following acute hypoxic exercise.

    Science.gov (United States)

    Katayama, Keisho; Yamashita, Shin; Iwamoto, Erika; Ishida, Koji

    2016-01-01

    The purpose of this study was to elucidate the effect of acute aerobic exercise performed under hypoxic conditions on flow-mediated dilation (FMD) in the inactive limb. Seven males participated in the study. The subjects performed two submaximal leg cycling on a semirecumbent ergometer at the same relative intensity (60% peak oxygen uptake) in normoxia [inspired oxygen fraction (FIO2) = 0·21] and hypoxia (FIO2 = 0·12-0·13) for 30 min. The brachial artery diameter and blood velocity during exercise were measured via ultrasound, and the antegrade and retrograde shear rates were calculated. Before and 5, 30 and 60 min after exercise, brachial artery FMD was measured in normoxia. FMD was estimated as the percentage increase in peak diameter from the baseline diameter at prior occlusion (%FMD) and as the controlling changes in baseline diameter (the corrected-%FMD). No difference in antegrade shear rate during exercise was detected between the normoxic and hypoxic conditions, whereas the retrograde shear rate was larger during hypoxic exercise. The %FMD decreased significantly at 5 min after exercise in both normoxia and hypoxia, and it returned to pre-exercise levels within 60 min of recovery. Significant decreases in FMD at 5 min after exercise had disappeared when the baseline diameter was controlled using an analysis of covariance (the corrected-%FMD). No significant differences were observed between the normoxic and hypoxic trials in the %FMD and corrected-%FMD following exercise. These results suggest that hypoxia has no impact on endothelial function in the inactive limb following acute aerobic exercise. PMID:25257848

  11. Long Lasting Local and Systemic Inflammation after Cerebral Hypoxic ischemia in Newborn Mice

    OpenAIRE

    Max Winerdal; Malin Elisabeth Winerdal; Johan Kinn; Vijay Urmaliya; Ola Winqvist; Ulrika Adén

    2012-01-01

    BACKGROUND: Hypoxic ischemia (HI) is an important cause of neonatal brain injury and subsequent inflammation affects neurological outcome. In this study we performed investigations of systemic and local activation states of inflammatory cells from innate and adaptive immunity at different time points after neonatal HI brain injury in mice. METHODOLOGY/PRINCIPAL FINDINGS: We developed a multiplex flow cytometry based method combined with immunohistochemistry to investigate cellular immune resp...

  12. Reactive Nitrogen Species in Mitochondria and Their Implications in Plant Energy Status and Hypoxic Stress Tolerance

    OpenAIRE

    Gupta, Kapuganti Jagadis; Abir U Igamberdiev

    2016-01-01

    Hypoxic and anoxic conditions result in the energy crisis that leads to cell damage. Since mitochondria are the primary organelles for energy production, the support of these organelles in a functional state is an important task during oxygen deprivation. Plant mitochondria adapted the strategy to survive under hypoxia by keeping electron transport operative even without oxygen via the use of nitrite as a terminal electrons acceptor. The process of nitrite reduction to nitric oxide (NO) in th...

  13. Immunocytochemical labelling of aerobic and hypoxic mammalian cells using a platinated derivative of EF5.

    OpenAIRE

    Matthews, J.; Adomat, H.; Farrell, N; King, P.; Koch, C.; Lord, E.; Palcic, B.; Poulin, N; Sangulin, J.; Skov, K.

    1996-01-01

    The monoclonal antibody ELK3-51 was previously developed to detect adducts of the 2-nitroimidazole EF5. Direct immunofluorescence was used to detect adducts of EF5 or of a platinated derivative cis-[PtCl2(NH3)EF5] in SCCVII cells treated under aerobic or hypoxic conditions. Fluorescence measurements of these cells using both image and flow cytometric methods were compared, giving similar profiles. Platination significantly decreased immunofluorescence levels (approximately 4-fold less than EF...

  14. MicroRNA expression and function in neonatal hypoxic ischaemic encephalopathy

    OpenAIRE

    Looney, Ann-Marie

    2016-01-01

    Hypoxic ischaemic encephalopathy (HIE) is a devastating neonatal condition which affects 2-3 per 1000 infants annually. The current gold standard of treatment - induced hypothermia, has the ability to reduce neonatal mortality and improve neonatal morbidity. However, to be effective it needs to be initiated within the therapeutic window which exists following initial insult until approximately 6 hours after birth. Current methods of assessment which are relied upon to identify infants with HI...

  15. Influence of CO2 Concentration on Adsorption Behavior of 99Tc in Clay Under Hypoxic Conditions

    Institute of Scientific and Technical Information of China (English)

    SONG; Zhi-xin; BAO; Liang-jin; JIANG; Tao; CHEN; Xi

    2013-01-01

    Under hypoxic conditions,using the Beishan groundwater the influence of the CO2 concentration on the adsorption behavior of 99Tc in the Longdong clay was studied by batch method.Meanwhile,the buffering effect of clay rocks on the pH value of aqueous solution at different CO2 concentrations was discussed.The adsorption behavior of 99Tc on clay at different initial pH values was also researched.

  16. Dynamic hypoxic zones in Lake Erie compress fish habitat, altering vulnerability to fishing gears

    Science.gov (United States)

    Kraus, Richard T.; Knight, Carey T.; Farmer, Troy M.; Gorman, Ann Marie; Collingsworth, Paris D.; Warren, Glenn J.; Kocovsky, Patrick M.; Conroy, Joseph D.

    2015-01-01

    Seasonal degradation of aquatic habitats from hypoxia occurs in numerous freshwater and coastal marine systems and can result in direct mortality or displacement of fish. Yet, fishery landings from these systems are frequently unresponsive to changes in the severity and extent of hypoxia, and population-scale effects have been difficult to measure except in extreme hypoxic conditions with hypoxia-sensitive species. We investigated fine-scale temporal and spatial variability in dissolved oxygen in Lake Erie as it related to fish distribution and catch efficiencies of both active (bottom trawls) and passive (trap nets) fishing gears. Temperature and dissolved oxygen loggers placed near the edge of the hypolimnion exhibited much higher than expected variability. Hypoxic episodes of variable durations were frequently punctuated by periods of normoxia, consistent with high-frequency internal waves. High-resolution interpolations of water quality and hydroacoustic surveys suggest that fish habitat is compressed during hypoxic episodes, resulting in higher fish densities near the edges of hypoxia. At fixed locations with passive commercial fishing gear, catches with the highest values occurred when bottom waters were hypoxic for intermediate proportions of time. Proximity to hypoxia explained significant variation in bottom trawl catches, with higher catch rates near the edge of hypoxia. These results emphasize how hypoxia may elevate catch rates in various types of fishing gears, leading to a lack of association between indices of hypoxia and fishery landings. Increased catch rates of fish at the edges of hypoxia have important implications for stock assessment models that assume catchability is spatially homogeneous.

  17. Clusterin and chemotherapy sensitivity under normoxic and graded hypoxic conditions in colorectal cancer.

    LENUS (Irish Health Repository)

    Kevans, David

    2012-06-01

    In vitro studies have shown that clusterin modulates treatment sensitivity in a number of human cancers; however, the interaction between clusterin expression and hypoxia in controlling treatment response in CRC has not previously been examined. The aim of this study was to assess the effect of clusterin overexpression in CRC cells on sensitivity to 5-fluorouracil (5-FU), oxaliplatin and FOLFOX treatment under normoxic and graded hypoxic conditions.

  18. 高原习服与低氧预适应%Altitude acclimatization and hypoxic preconditioning

    Institute of Scientific and Technical Information of China (English)

    陈良恩

    2012-01-01

    Altitude hypoxia often results in acute mountain sickness. Altitude acclimatization is a series of adaptive changes for body to deal with a hypoxic environment. The best strategy to prevent or alleviate acute mountain sickness is to search for measures effective in improving acclimation ability and shortening the acclimation time. Hypoxic ' preconditioning strengthens the organisms innate ability to resist more severe hypoxia (and/or for longer times) after one or more transitory, immortal hypoxic stimulations. As an efficient method for enhancing anoxic tolerance by inducing endogenous protective mechanisms, hypoxic preconditioning is an important measure to promote altitude acclimatization.%高原低氧易导致急性高原反应,高原习服是机体为适应高原低氧环境发生的一系列代偿适应性变化.寻找加快高原习服的有效措施,提高机体高原习服能力,是预防和减轻急性高原反应的最好策略.低氧预适应是指机体经一次或多次短暂、非致死性低氧刺激后,机体获得的对后续更长时间或更严重低氧性损伤的耐受性.低氧预适应作为一种通过内源性保护机制来提高机体缺氧耐力的有效方法,是促进高原习服的重要措施.

  19. Zooplankton variation in relation to hydrology in an enclosed hypoxic bay (Amvrakikos Gulf, Greece

    Directory of Open Access Journals (Sweden)

    G. KEHAYIAS

    2014-09-01

    Full Text Available This study investigated the temporal and spatial variation of the zooplankton community of a hypoxic coastal embayment (Amvrakikos Gulf, western Greece in relation to hydrological characteristics during an annual cycle. The main hydrological feature was the prolonged water stratification, which determined hypoxic conditions in the deeper layers that became anoxic close to the bottom in September, while vertical mixing occurred for a very short period (October-November. The total zooplankton abundance fluctuated between 44.6 and 159.7 ind l-1. Fourteen groups were recorded, among which copepods dominated accounting on average for 86.4 %. Most of the groups presented higher abundance values in winter and spring when increased chlorophyll-α concentrations were found. Oxygen depletion affects the vertical distribution of most zooplankton groups and the vertical habitat partitioning between copepod orders and their ontogenetic stages. Several taxa were recorded even in the deep, anoxic layers, but only the polychaete larvae increased in abundance with depth. Calanoids, appendicularians and bivalve larvae presented eastward decrease of abundance in the deepest layers following the same pattern of oxygen decrease. Notwithstanding hypoxic conditions in its deepest layers, Amvrakikos Gulf was accounted for a mesotrophic ecosystem, with the nutrient concentration being lower than in the past. Several biotic elements indicate that the gulf is in a transitional phase towards a better quality state and these results reinforce the need for consistent monitoring of this ecosystem.

  20. Mutual regulation between SIAH2 and DYRK2 controls hypoxic and genotoxic signaling pathways.

    Science.gov (United States)

    Pérez, Moisés; García-Limones, Carmen; Zapico, Inés; Marina, Anabel; Schmitz, M Lienhard; Muñoz, Eduardo; Calzado, Marco A

    2012-10-01

    The ubiquitin E3 ligase SIAH2 is an important regulator of the hypoxic response as it leads to the ubiquitin/proteasomal degradation of prolyl hydroxylases such as PHD3, which in turn increases the stability of hypoxia-inducible factor (HIF)-1α. In the present study, we identify the serine/threonine kinase DYRK2 as SIAH2 interaction partner that phosphorylates SIAH2 at five residues (Ser16, Thr26, Ser28, Ser68, and Thr119). Phosphomimetic and phospho-mutant forms of SIAH2 exhibit different subcellular localizations and consequently change in PHD3 degrading activity. Accordingly, phosphorylated SIAH2 is more active than the wild-type E3 ligase and shows an increased ability to trigger the HIF-1α-mediated transcriptional response and angiogenesis. We also found that SIAH2 knockdown increases DYRK2 stability, whereas SIAH2 expression facilitates DYRK2 polyubiquitination and degradation. Hypoxic conditions cause a SIAH2-dependent DYRK2 polyubiquitination and degradation which ultimately also results in an impaired SIAH2 phosphorylation. Similarly, DYRK2-mediated phosphorylation of p53 at Ser46 is impaired under hypoxic conditions, suggesting a molecular mechanism underlying chemotherapy resistance in solid tumors. PMID:22878263

  1. Neuroprotective actions of taurine on hypoxic-ischemic brain damage in neonatal rats.

    Science.gov (United States)

    Zhu, Xiao-Yun; Ma, Peng-Sheng; Wu, Wei; Zhou, Ru; Hao, Yin-Ju; Niu, Yang; Sun, Tao; Li, Yu-Xiang; Yu, Jian-Qiang

    2016-06-01

    Taurine is an abundant amino acid in the nervous system, which has been proved to possess antioxidation, osmoregulation and membrane stabilization. Previously it has been demonstrated that taurine exerts ischemic brain injury protective effect. This study was designed to investigate whether the protective effect of taurine has the possibility to be applied to treat neonatal hypoxic-ischemic brain damage. Seven-day-old Sprague-Dawley rats were treated with left carotid artery ligation followed by exposure to 8% oxygen to generate the experimental group. The cerebral damage area was measured after taurine post-treatment with 2,3,5-triphenyltetrazolium chloride (TTC) staining, Hematoxyline-Eosin (HE) staining and Nissl staining. The activities of superoxide dismutase (SOD), malondialdehyde (MDA), glutathione peroxidase (GSH-Px), total antioxidant capacity (T-AOC), myeloperoxtidase (MPO), ATP and Lactic Acid productions were assayed with ipsilateral hemisphere homogenates. Western-blot and immunofluorescence assay were processed to detect the expressions of AIF, Cyt C, Bax, Bcl-2 in brain. We found that taurine significantly reduced brain infarct volume and ameliorated morphological injury obviously reversed the changes of SOD, MDA, GSH-Px, T-AOC, ATP, MPO, and Lactic Acid levels. Compared with hypoxic-ischemic group, it showed marked reduction of AIF, Cyt C and Bax expressions and increase of Bcl-2 after post-treatment. We conclude that taurine possesses an efficacious neuroprotective effect after cerebral hypoxic-ischemic damage in neonatal rats. PMID:27345710

  2. Carotid chemoreceptors do not mediate hypoxic-induced gasping and autoresuscitation in newborn rats.

    Science.gov (United States)

    Lun, Rongzhi; Zhang, Chunfen; Fewell, James E

    2015-07-01

    Experiments were carried out on 48, 5-6-day-old rat pups to investigate the influence of carotid denervation on their time to last gasp during a single period of hypoxia, and on their ability to autoresuscitate from primary apnea during repeated hypoxic challenge. One group of pups was studied with intact carotid chemoreceptors and one group was studied following surgical denervation of the carotid chemoreceptors. Carotid denervation eliminated the early tachypneic phase during exposure to hypoxia and delayed the time to arousal/excitement but did not alter the time to primary apnea, the time to last gasp or the total number of gasps during exposure to a single period of unrelenting hypoxia. Furthermore, carotid denervation did not alter the number of successful autoresuscitations from primary apnea during repeated hypoxic exposure. Thus, the carotid chemoreceptors are not essential for the initiation or maintenance of gasping nor are they are integral to gasping effecting successful autoresuscitation from hypoxic-induced apnea in newborn rats.

  3. Reactive nitrogen species in mitochondria and their implications in plant energy status and hypoxic stress tolerance

    Directory of Open Access Journals (Sweden)

    Kapuganti Jagadis Gupta

    2016-03-01

    Full Text Available Hypoxic and anoxic conditions result in the energy crisis that leads to cell damage. Since mitochondria are the primary organelles for energy production, the support of these organelles in a functional state is an important task during oxygen deprivation. Plant mitochondria adapted the strategy to survive under hypoxia by keeping electron transport operative even without oxygen via the use of nitrite as a terminal electrons acceptor. The process of nitrite reduction to nitric oxide (NO in the mitochondrial electron transport chain recycles NADH and leads to a limited rate of ATP production. The produced ATP alongside with the ATP generated by fermentation supports the processes of transcription and translation required for hypoxic survival and recovery of plants. Non-symbiotic hemoglobins (called phytoglobins in plants scavenge NO and thus contribute to regeneration of NAD+ and nitrate required for the operation of anaerobic energy metabolism. This overall operation represents an important strategy of biochemical adaptation that results in the improvement of energy status and thereby in protection of plants in the conditions of hypoxic stress.

  4. Neuroprotective effects of ginsenoside Rg1-induced neural stem cell transplantation on hypoxic-ischemic encephalopathy

    Institute of Scientific and Technical Information of China (English)

    Ying-bo Li; Yan Wang; Ji-ping Tang; Di Chen; Sha-li Wang

    2015-01-01

    Ginsenoside Rg1 is the major pharmacologically active component of ginseng, and is reported to have various therapeutic actions. To determine whether it induces the differentiation of neural stem cells, and whether neural stem cell transplantation after induction has therapeutic effects on hypoxic-ischemic encephalopathy, we cultured neural stem cells in 10–80 μM ginsenoside Rg1. Immunohistochemistry revealed that of the concentrations tested, 20 mM ginsenoside Rg1 had the greatest differentiation-inducing effect and was the concentration used for subsequent exper-iments. Whole-cell patch clamp showed that neural stem cells induced by 20 μM ginsenoside Rg1 were more mature than non-induced cells. We then established neonatal rat models of hypox-ic-ischemic encephalopathy using the suture method, and ginsenoside Rg1-induced neural stem cells were transplantedvia intracerebroventricular injection. These tests conifrmed that neural stem cells induced by ginsenoside had fewer pathological lesions and had a signiifcantly better behavioral capacity than model rats that received saline. Transplanted neural stem cells expressed neuron-speciifc enolase, and were mainly distributed in the hippocampus and cerebral cortex. The present data suggest that ginsenoside Rg1-induced neural stem cells can promote the partial recovery of complicated brain functions in models of hypoxic-ischemic encephalopathy.

  5. Thioperamide treats neonatal hypoxic-ischemic encephalopathy by postsynaptic H1 receptors*

    Institute of Scientific and Technical Information of China (English)

    Feiyong Jia; Lin Du; Yunpeng Hao; Shicheng Liu; Ning Li; Huiyi Jiang

    2013-01-01

    Thioperamide, a selective histamine H3 receptor antagonist, can increase histamine content in the brain, improve brain edema, and exert a neuroprotective effect. This study aimed to examine the mechanism of action of thioperamide during brain edema in a rat model of neonatal hypoxic- is-chemic encephalopathy. Our results showed that thioperamide significantly decreased brain water content and malondialdehyde levels, while significantly increased histamine levels and superoxide dismutase activity in the hippocampus. This evidence demonstrates that thioperamide could pre-vent oxidative damage and attenuate brain edema fol owing neonatal hypoxic-ischemic encepha-lopathy. We further observed that changes in the above indexes occurred after combined treatment of thioperamide with the H1 receptor antagonist, pyrilamine, and the H2 receptor antagonist, ci-metidine. Experimental findings indicated that pyrilamine reversed the effects of thioperamide;however, cimetidine had no significant influence on the effects of thioperamide. Our present findings suggest that thioperamide can increase brain histamine content and attenuate brain edema and oxidative damage by acting in combination with postsynaptic H1 receptors in a rat model of neo-natal hypoxic-ischemic encephalopathy.

  6. Periostin Promotes Neural Stem Cell Proliferation and Differentiation following Hypoxic-Ischemic Injury.

    Directory of Open Access Journals (Sweden)

    Si-Min Ma

    Full Text Available Neural stem cell (NSC proliferation and differentiation are required to replace neurons damaged or lost after hypoxic-ischemic events and recover brain function. Periostin (POSTN, a novel matricellular protein, plays pivotal roles in the survival, migration, and regeneration of various cell types, but its function in NSCs of neonatal rodent brain is still unknown. The purpose of this study was to investigate the role of POSTN in NSCs following hypoxia-ischemia (HI. We found that POSTN mRNA levels significantly increased in differentiating NSCs. The proliferation and differentiation of NSCs in the hippocampus is compromised in POSTN knockout mice. Moreover, NSC proliferation and differentiation into neurons and astrocytes significantly increased in cultured NSCs treated with recombinant POSTN. Consistently, injection of POSTN into neonatal hypoxic-ischemic rat brains stimulated NSC proliferation and differentiation in the subventricular and subgranular zones after 7 and 14 days of brain injury. Lastly, POSTN treatment significantly improved the spatial learning deficits of rats subjected to HI. These results suggest that POSTN significantly enhances NSC proliferation and differentiation after HI, and provides new insights into therapeutic strategies for the treatment of hypoxic-ischemic encephalopathy.

  7. Radiosensitization and hypoxic cell toxicity of NLA-1 and NLA-2, two new bioreductive compounds

    Energy Technology Data Exchange (ETDEWEB)

    Papadopoulou, M.V.; Epperly, M.W.; Shields, D.S. (Pittsburgh Cancer Institute PA (USA)); Bloomer, W.D.

    1992-04-01

    Two new bioreductive compounds, 9-(3-(2-nitro-1-imidazolyl)propylamino)acridine hydrochloride (NLA-1) and 9-(2-(2-nitro-1-imidazolyl)ethylamino)acridine hydrochloride (NLA-2), have been prepared. They feature an acridine ring to intercalate with DNA, a 2-nitroimidazole ring as the radiosensitizing moiety and an amino functionality for increased DNA-binding and hydrophilicity. Time concentration dependent cytotoxicity as well as radiosensitization efficacy of the two compounds under hypoxic or aerobic conditions were determined in vitro using V-79 cells and an MTT colorimetric or clonogenic assay. The isosensitization point (ISP), defined as that drug concentration which results in the same survival decrement upon exposure of hypoxic of oxygenated cells to a given radiation dose, has been determined for both compounds at 7.5 Gy and the values are significantly lower than the ISPs of 5-(3-(2-nitro-1-imidazolyl)propyl)phenanthridinium bromide, 2-(2-nitro-1-imidazolyl)ethylamine or misonidazole (MISO). NLA-1 and NLA-2 are potent hypoxic cytotoxins and on a concentration basis, more potent than MISO as radiosensitizers in vitro. The sensitization enhancement ratios were significantly increased when 1 h drug preincubation under hypoxia at 37degC was applied, before irradiation at room temperature. (author).

  8. Neuroprotective effects of ginsenoside Rg1-induced neural stem cell transplantation on hypoxic-ischemic encephalopathy

    Directory of Open Access Journals (Sweden)

    Ying-bo Li

    2015-01-01

    Full Text Available Ginsenoside Rg1 is the major pharmacologically active component of ginseng, and is reported to have various therapeutic actions. To determine whether it induces the differentiation of neural stem cells, and whether neural stem cell transplantation after induction has therapeutic effects on hypoxic-ischemic encephalopathy, we cultured neural stem cells in 10-80 µM ginsenoside Rg1. Immunohistochemistry revealed that of the concentrations tested, 20 mM ginsenoside Rg1 had the greatest differentiation-inducing effect and was the concentration used for subsequent experiments. Whole-cell patch clamp showed that neural stem cells induced by 20 µM ginsenoside Rg1 were more mature than non-induced cells. We then established neonatal rat models of hypoxic-ischemic encephalopathy using the suture method, and ginsenoside Rg1-induced neural stem cells were transplanted via intracerebroventricular injection. These tests confirmed that neural stem cells induced by ginsenoside had fewer pathological lesions and had a significantly better behavioral capacity than model rats that received saline. Transplanted neural stem cells expressed neuron-specific enolase, and were mainly distributed in the hippocampus and cerebral cortex. The present data suggest that ginsenoside Rg1-induced neural stem cells can promote the partial recovery of complicated brain functions in models of hypoxic-ischemic encephalopathy.

  9. Mutual regulation between SIAH2 and DYRK2 controls hypoxic and genotoxic signaling pathways

    Institute of Scientific and Technical Information of China (English)

    Moisés Pérez; Carmen García-Limones; Inés Zapico; Anabel Marina; M. Lienhard Schmitz; Eduardo Mu(n)oz; Marco A. Calzado

    2012-01-01

    The ubiquitin E3 ligase SIAH2 is an important regulator of the hypoxic response as it leads to the ubiquitin/proteasomal degradation of prolyl hydroxylases such as PHD3,which in turn increases the stability of hypoxia-inducible factor (HIF)-1α.In the present study,we identify the serine/threonine kinase DYRK2 as SIAH2 interaction partner that phosphorylates SIAH2 at five residues (Ser16,Thr26,Ser28,Ser68,and Thr119).Phosphomimetic and phospho-mutant forms of SIAH2 exhibit different subcellular localizations and consequently change in PHD3 degrading activity.Accordingly,phosphorylated SIAH2 is more active than the wild-type E3 ligase and shows an increased ability to trigger the HIF-1α-mediated transcriptional response and angiogenesis.We also found that SIAH2 knockdown increases DYRK2 stability,whereas SIAH2 expression facilitates DYRK2 polyubiquitination and degradation.Hypoxic conditions cause a SIAH2-dependent DYRK2 polyubiquitination and degradation which ultimately also results in an impaired SIAH2 phosphorylation.Similarly,DYRK2-mediated phosphorylation of p53 at Ser46 is impaired under hypoxic conditions,suggesting a molecular mechanism underlying chemotherapy resistance in solid tumors.

  10. Acute high-altitude hypoxic brain injury Identification of ten differential proteins

    Institute of Scientific and Technical Information of China (English)

    Jianyu Li; Yuting Qi; Hui Liu; Ying Cui; Li Zhang; Haiying Gong; Yaxiao Li; Lingzhi Li; Yongliang Zhang

    2013-01-01

    Hypobaric hypoxia can cause severe brain damage and mitochondrial dysfunction, and is involved in hypoxic brain injury. However, little is currently known about the mechanisms responsible for mi-tochondrial dysfunction in hypobaric hypoxic brain damage. In this study, a rat model of hypobaric hypoxic brain injury was established to investigate the molecular mechanisms associated with mi-tochondrial dysfunction. As revealed by two-dimensional electrophoresis analysis, 16, 21, and 36 differential protein spots in cerebral mitochondria were observed at 6, 12, and 24 hours post-hypobaric hypoxia, respectively. Furthermore, ten protein spots selected from each hypobaric hypoxia subgroup were similarly regulated and were identified by mass spectrometry. These de-tected proteins included dihydropyrimidinase-related protein 2, creatine kinase B-type, isova-leryl-CoA dehydrogenase, elongation factor Ts, ATP synthase beta-subunit, 3-mercaptopyruvate sulfurtransferase, electron transfer flavoprotein alpha-subunit, Chain A of 2-enoyl-CoA hydratase, NADH dehydrogenase iron-sulfur protein 8 and tropomyosin beta chain. These ten proteins are al involved in the electron transport chain and the function of ATP synthase. Our findings indicate that hypobaric hypoxia can induce the differential expression of several cerebral mitochondrial proteins, which are involved in the regulation of mitochondrial energy production.

  11. Post-hypoxic recovery of respiratory rhythm generation is gender dependent.

    Directory of Open Access Journals (Sweden)

    Alfredo J Garcia

    Full Text Available The preBötzinger complex (preBötC is a critical neuronal network for the generation of breathing. Lesioning the preBötC abolishes respiration, while when isolated in vitro, the preBötC continues to generate respiratory rhythmic activity. Although several factors influence rhythmogenesis from this network, little is known about how gender may affect preBötC function. This study examines the influence of gender on respiratory activity and in vitro rhythmogenesis from the preBötC. Recordings of respiratory activity from neonatal mice (P10-13 show that sustained post-hypoxic depression occurs with greater frequency in males compared to females. Moreover, extracellular population recordings from the preBötC in neonatal brainstem slices (P10-13 reveal that the time to the first inspiratory burst following reoxygenation (TTFB is significantly delayed in male rhythmogenesis when compared to the female rhythms. Altering activity of ATP sensitive potassium channels (KATP with either the agonist, diazoxide, or the antagonist, tolbutamide, eliminates differences in TTFB. By contrast, glucose supplementation improves post-hypoxic recovery of female but not male rhythmogenesis. We conclude that post-hypoxic recovery of respiration is gender dependent, which is, in part, centrally manifested at the level of the preBötC. Moreover, these findings provide potential insight into the basis of increased male vulnerability in a variety of conditions such as Sudden Infant Death Syndrome (SIDS.

  12. Mutual regulation between SIAH2 and DYRK2 controls hypoxic and genotoxic signaling pathways.

    Science.gov (United States)

    Pérez, Moisés; García-Limones, Carmen; Zapico, Inés; Marina, Anabel; Schmitz, M Lienhard; Muñoz, Eduardo; Calzado, Marco A

    2012-10-01

    The ubiquitin E3 ligase SIAH2 is an important regulator of the hypoxic response as it leads to the ubiquitin/proteasomal degradation of prolyl hydroxylases such as PHD3, which in turn increases the stability of hypoxia-inducible factor (HIF)-1α. In the present study, we identify the serine/threonine kinase DYRK2 as SIAH2 interaction partner that phosphorylates SIAH2 at five residues (Ser16, Thr26, Ser28, Ser68, and Thr119). Phosphomimetic and phospho-mutant forms of SIAH2 exhibit different subcellular localizations and consequently change in PHD3 degrading activity. Accordingly, phosphorylated SIAH2 is more active than the wild-type E3 ligase and shows an increased ability to trigger the HIF-1α-mediated transcriptional response and angiogenesis. We also found that SIAH2 knockdown increases DYRK2 stability, whereas SIAH2 expression facilitates DYRK2 polyubiquitination and degradation. Hypoxic conditions cause a SIAH2-dependent DYRK2 polyubiquitination and degradation which ultimately also results in an impaired SIAH2 phosphorylation. Similarly, DYRK2-mediated phosphorylation of p53 at Ser46 is impaired under hypoxic conditions, suggesting a molecular mechanism underlying chemotherapy resistance in solid tumors.

  13. Bumetanide enhances phenobarbital efficacy in a rat model of hypoxic neonatal seizures.

    Directory of Open Access Journals (Sweden)

    Ryan T Cleary

    Full Text Available Neonatal seizures can be refractory to conventional anticonvulsants, and this may in part be due to a developmental increase in expression of the neuronal Na(+-K(+-2 Cl(- cotransporter, NKCC1, and consequent paradoxical excitatory actions of GABAA receptors in the perinatal period. The most common cause of neonatal seizures is hypoxic encephalopathy, and here we show in an established model of neonatal hypoxia-induced seizures that the NKCC1 inhibitor, bumetanide, in combination with phenobarbital is significantly more effective than phenobarbital alone. A sensitive mass spectrometry assay revealed that bumetanide concentrations in serum and brain were dose-dependent, and the expression of NKCC1 protein transiently increased in cortex and hippocampus after hypoxic seizures. Importantly, the low doses of phenobarbital and bumetanide used in the study did not increase constitutive apoptosis, alone or in combination. Perforated patch clamp recordings from ex vivo hippocampal slices removed following seizures revealed that phenobarbital and bumetanide largely reversed seizure-induced changes in EGABA. Taken together, these data provide preclinical support for clinical trials of bumetanide in human neonates at risk for hypoxic encephalopathy and seizures.

  14. Blood carbon dioxide levels and adverse outcome in neonatal hypoxic-ischemic encephalopathy.

    LENUS (Irish Health Repository)

    Nadeem, Montasser

    2012-01-31

    We investigated pCO(2) patterns and the relationship between pCO(2) levels and neurodevelopmental outcome in term infants with hypoxic-ischemic encephalopathy. Blood gases during the first 72 hours of life were collected from 52 infants with hypoxic-ischemic encephalopathy. Moderate hypocapnia (pCO(2) <3.3 kPa), severe hypocapnia (pCO(2) <2.6 kPa), and hypercapnia (pCO(2) >6.6 kPa) were correlated to neurodevelopmental outcome at 24 months. Normocapnia was documented in 416\\/551 (75.5%) of samples and was present during the entire 72 hours in only 6 out of 52 infants. Mean (standard deviation) pCO(2) values did not differ between infants with normal and abnormal outcomes: 5.43 (2.4) and 5.41 (2.03), respectively. There was no significant association between moderate hypocapnia, severe hypocapnia, or hypercapnia and adverse outcome (odds ratio [OR] = 1.84, 95% confidence interval [CI] = 0.49 to 6.89; OR = 3.16, CI = 0.14 to 28.45; and OR = 1.07, CI = 0.24 to 5.45, respectively). In conclusion, only one in nine newborns had normocapnia throughout the first 72 hours. Severe hypocapnia was rare and occurred only in ventilated babies. Hypercapnia and hypocapnia in infants with hypoxic-ischemic encephalopathy during the first 72 hours of life were not associated with adverse outcome.

  15. Compensatory vasodilatation during hypoxic exercise: mechanisms responsible for matching oxygen supply to demand

    Science.gov (United States)

    Casey, Darren P; Joyner, Michael J

    2012-01-01

    Hypoxia can have profound influences on the circulation. In humans, acute exposure to moderate hypoxia has been demonstrated to result in vasodilatation in the coronary, cerebral, splanchnic and skeletal muscle vascular beds. The combination of submaximal exercise and hypoxia produces a ‘compensatory’ vasodilatation and augmented blood flow in contracting skeletal muscles relative to the same level of exercise under normoxic conditions. This augmented vasodilatation exceeds that predicted by a simple sum of the individual dilator responses to hypoxia alone and normoxic exercise. Additionally, this enhanced hypoxic exercise hyperaemia is proportional to the hypoxia-induced fall in arterial oxygen (O2) content, thus preserving muscle O2 delivery and ensuring it is matched to demand. Several vasodilator pathways have been proposed and examined as likely regulators of skeletal muscle blood flow in response to changes in arterial O2 content. The purpose of this review is to put into context the present evidence regarding mechanisms responsible for the compensatory vasodilatation observed during hypoxic exercise in humans. Along these lines, this review will highlight the interactions between various local metabolic and endothelial derived substances that influence vascular tone during hypoxic exercise. PMID:22988134

  16. Preferential kill of hypoxic EMT6 mammary tumor cells by the bioreductive alkylating agent porfiromycin.

    Science.gov (United States)

    Sartorelli, A C; Belcourt, M F; Hodnick, W F; Keyes, S R; Pritsos, C A; Rockwell, S

    1995-01-01

    Hypoxic cells in solid tumors represent a therapeutically resistant population that limits the curability of many solid tumors by irradiation and by most chemotherapeutic agents. The oxygen deficit, however, creates an environment conducive to reductive processes; this results in a major exploitable difference between normal and neoplastic tissues. The mitomycin antibiotics can be reductively activated by a number of oxidoreductases, in a process required for the production of their therapeutic effects. Preferential activation of these drugs under hypoxia and greater toxicity to oxygen-deficient cells than to their oxygenated counterparts are obtained in most instances. The demonstration that mitomycin C and porfiromycin, used to kill the hypoxic fraction, in combination with irradiation, to eradicate the oxygenated portion of the tumor, produced enhanced cytodestructive effects on solid tumors in animals has led to the clinical evaluation of the mitomycins in combination with radiation therapy in patients with head and neck cancer. The findings from these clinical trials have demonstrated the value of directing a concerted therapeutic attack on the hypoxic fraction of solid tumors as an approach toward enhancing the curability of localized neoplasms by irradiation. PMID:7572339

  17. Chronic anaemia, hyperbaric oxygen and tumour radiosensitivity

    Energy Technology Data Exchange (ETDEWEB)

    McCormack, M.; Nias, A.H.W.; Smith, Eileen (Saint Thomas' Hospital, London (UK). Richard Dimbleby Research Lab.)

    1990-10-01

    The present study examined the relationship between anaemia and tumour response to radiation given in air or HPO in C{sub 3}H mice transplanted with a mammary adenocarcinoma using a growth delay assay to assess radiation response. Radiation studies with these anaemic mice demonstrated that the tumour radiosensitivity was decreased when treatment was given in air. HPO was successful in overcoming the increased radioresistance associated with anaemia. This result suggested that tumours grown in anaemic mice have a higher hypoxic fraction than those grown in control mice. Changes in host physiology with chronic anaemia may contribute to the benefit seen with HPO but such alterations per se may be inadequate to maintain tumour oxygenation when treatment is given in air. (author).

  18. Towards a mouse model of depression : a psychoneuroendocrine approach

    NARCIS (Netherlands)

    Dalm, Sergiu

    2012-01-01

    Chronic stress is considered a vulnerability factor for depression. A key symptom is anhedonia; a reduced response to positive stimuli. Drugs are effective for only 20-40% of the patients and new drugs are urgently needed. The objective of the research was to develop a mouse model of depression that

  19. NOD mouse model for Sjogren's syndrome: lack of longitudinal stability

    NARCIS (Netherlands)

    B.M. Lodde; F. Mineshiba; M.R. Kok; J. Wang; C. Zheng; M. Schmidt; A.P. Cotrim; M. Kriete; P.P. Tak; B.J. Baum

    2006-01-01

    OBJECTIVES: The non-obese diabetic (NOD) mouse is not only a widely used model for diabetes mellitus type I, but also for the chronic autoimmune disease Sjogren's syndrome (SS), mainly affecting salivary and lacrimal glands. We studied the efficacy of local recombinant serotype 2 adeno-associated vi

  20. The MOUSE Squad

    Science.gov (United States)

    Borja, Rhea R.

    2004-01-01

    This article presents a New York city after-school program started by MOUSE (Making Opportunities for Upgrading Schools and Education), a national nonprofit group that teaches students how to fix computers, and equips them with the communication and problem-solving skills to help them in the working world. The MOUSE program is part of a trend…

  1. Mouse genome database 2016.

    Science.gov (United States)

    Bult, Carol J; Eppig, Janan T; Blake, Judith A; Kadin, James A; Richardson, Joel E

    2016-01-01

    The Mouse Genome Database (MGD; http://www.informatics.jax.org) is the primary community model organism database for the laboratory mouse and serves as the source for key biological reference data related to mouse genes, gene functions, phenotypes and disease models with a strong emphasis on the relationship of these data to human biology and disease. As the cost of genome-scale sequencing continues to decrease and new technologies for genome editing become widely adopted, the laboratory mouse is more important than ever as a model system for understanding the biological significance of human genetic variation and for advancing the basic research needed to support the emergence of genome-guided precision medicine. Recent enhancements to MGD include new graphical summaries of biological annotations for mouse genes, support for mobile access to the database, tools to support the annotation and analysis of sets of genes, and expanded support for comparative biology through the expansion of homology data.

  2. Hypoxic regulation of cytoglobin and neuroglobin expression in human normal and tumor tissues

    Directory of Open Access Journals (Sweden)

    Emara Marwan

    2010-09-01

    Full Text Available Abstract Background Cytoglobin (Cygb and neuroglobin (Ngb are recently identified globin molecules that are expressed in vertebrate tissues. Upregulation of Cygb and Ngb under hypoxic and/or ischemic conditions in vitro and in vivo increases cell survival, suggesting possible protective roles through prevention of oxidative damage. We have previously shown that Ngb is expressed in human glioblastoma multiforme (GBM cell lines, and that expression of its transcript and protein can be significantly increased after exposure to physiologically relevant levels of hypoxia. In this study, we extended this work to determine whether Cygb is also expressed in GBM cells, and whether its expression is enhanced under hypoxic conditions. We also compared Cygb and Ngb expression in human primary tumor specimens, including brain tumors, as well as in human normal tissues. Immunoreactivity of carbonic anhydrase IX (CA IX, a hypoxia-inducible metalloenzyme that catalyzes the hydration of CO2 to bicarbonate, was used as an endogenous marker of hypoxia. Results Cygb transcript and protein were expressed in human GBM cells, and this expression was significantly increased in most cells following 48 h incubation under hypoxia. We also showed that Cygb and Ngb are expressed in both normal tissues and human primary cancers, including GBM. Among normal tissues, Cygb and Ngb expression was restricted to distinct cell types and was especially prominent in ductal cells. Additionally, certain normal organs (e.g. stomach fundus, small bowel showed distinct regional co-localization of Ngb, Cygb and CA IX. In most tumors, Ngb immunoreactivity was significantly greater than that of Cygb. In keeping with previous in vitro results, tumor regions that were positively stained for CA IX were also positive for Ngb and Cygb, suggesting that hypoxic upregulation of Ngb and Cygb also occurs in vivo. Conclusions Our finding of hypoxic up-regulation of Cygb/Ngb in GBM cell lines and human

  3. Role of gap junction and connexin-43 in hypoxic-ischemic brain damage

    Institute of Scientific and Technical Information of China (English)

    Jieying Lin; Niyang Lin

    2006-01-01

    OBJECTEVE:Gap junctin (GJ)is the structural basis for direct intercellular communication of nerve cells . Connexin(Cx) is the protein subunit for constructling GJ channel. Among them, Cx43is closely related with nervous system. Both Cx43 and nervous system play an important role in the pathophysiological development of hypoxic-ischemic injury. We are in attempt to investigate GJ,Cx43 and their correlations with hypoxic-ischemic brain damage by research.DATA SOURCES:Using the terms "brain gap junction"in English and "gap junction"in Chinese, we searched the Medline database and Chinese BioMedical Literature Database as well as China Hospital Knowledge Database to identify the articles published from 1996 to 2006 about GJ and brain hypoxic-ischemic injury.STUDY SELECTION:The articles were selected firstly and abstracts of 250 articles were read thuugh.Articles in which the experimental design met randomized controlled principle were included,and study articles and case reports with repetitve contents were excluded.DATA EXTRACTION:Among 53 included correlative articles, 23 were excluded for repetitive contents and the other 30 were analyzed.DATA SYNTHESIS:GJ,widely esistling in nervous system,plays a key role in maintainling normal differentiation and development as well as physiological function brain tissue.GJ channel is a hydrophilic,low-selectivity and lowohmic channel, which can provide direct channel for intercellular substance transmission and information communication. It plays an important role in the differentiation and development of nerve cells and regulation of physiological function,The funtions of GJ channel are regulated by many factors,which invilved intracellular Ph value, Ca2+concentration, ATP concentration, phosphorylation of Cx, transchannel pressure,some neurohormonal factors,regulatory factors of protein and so on. Cx43 is the main component of GJ channel in the brain tissues. Its expression in the brain tissue of mammal is the strongest

  4. GLUT1 gene is a potential hypoxic marker in colorectal cancer patients

    International Nuclear Information System (INIS)

    Tumor hypoxia is an important factor related to tumor resistance to radiotherapy and chemotherapy. This study investigated molecules synthesized in colorectal cancer cells during hypoxia to explore the possibility of developing molecular probes capable of detecting cell death and/or the efficiency of radiotherapy and chemotherapy. At first, we incubated two human colorectal adenocarcinoma cell lines SW480 (UICC stage II) and SW620 (UICC stage III) cells in hypoxic (≤2% O2, 93% N2, and 5% CO2) and normoxic conditions (20% O2, 75% N2, and 5% CO2) for 24 h and 48 h. The relative expression ratio of GLUT1 mRNA in hypoxic conditions was analyzed by RT-PCR. Ten cancerous tissues collected from human colorectal cancer patients were examined. HIF-1α and HIF-2α levels were measured to indicate the degree of hypoxia, and gene expression under hypoxic conditions was determined. As a comparison, HIF-1α, HIF-2α, and GLUT1 levels were measured in the peripheral blood of 100 CRC patients. Hypoxia-induced lactate was found to be elevated 3.24- to 3.36-fold in SW480 cells, and 3.06- to 3.17-fold in SW620 cells. The increased relative expression ratio of GLUT1 mRNA, under hypoxic conditions was higher in SW620 cells (1.39- to 1.72-fold elevation) than in SW480 cells (1.24- to 1.66-fold elevation). HIF-1α and HIF-2α levels were elevated and GLUT1 genes were significantly overexpressed in CRC tissue specimens. The elevated ratio of GLUT1 was higher in stage III and IV CRC tissue specimens than in the stage I and II (2.97–4.73 versus 1.44–2.11). GLUT1 mRNA was also increased in the peripheral blood of stage II and III CRC patients as compared to stage I patients, suggesting that GLUT1 may serve as a hypoxic indicator in CRC patients. In conclusion, this study demonstrated that GLUT1 has the potential to be employed as a molecular marker to indicate the degree of hypoxia experienced by tumors circulating in the blood of cancer patients

  5. Chronic Treatment with a Water-Soluble Extract from the Culture Medium of Ganoderma lucidum Mycelia Prevents Apoptosis and Necroptosis in Hypoxia/Ischemia-Induced Injury of Type 2 Diabetic Mouse Brain

    Directory of Open Access Journals (Sweden)

    Meiyan Xuan

    2015-01-01

    Full Text Available Type 2 diabetes mellitus has been known to increase systemic oxidative stress by chronic hyperglycemia and visceral obesity and aggravate cerebral ischemic injury. On the basis of our previous study regarding a water-soluble extract from the culture medium of Ganoderma lucidum mycelia (designed as MAK, which exerts antioxidative and neuroprotective effects, the present study was conducted to evaluate the preventive effects of MAK on apoptosis and necroptosis (a programmed necrosis induced by hypoxia/ischemia (H/I in type 2 diabetic KKAy mice. H/I was induced by a combination of unilateral common carotid artery ligation with hypoxia (8% O2 for 20 min and subsequent reoxygenation. Pretreatment with MAK (1 g/kg, p.o. for a week significantly reduced H/I-induced neurological deficits and brain infarction volume assessed at 24 h of reoxygenation. Histochemical analysis showed that MAK significantly suppressed superoxide production, neuronal cell death, and vacuolation in the ischemic penumbra, which was accompanied by a decrease in the numbers of TUNEL- or cleaved caspase-3-positive cells. Furthermore, MAK decreased the expression of receptor-interacting protein kinase 3 mRNA and protein, a key molecule for necroptosis. These results suggest that MAK confers resistance to apoptotic and necroptotic cell death and relieves H/I-induced cerebral ischemic injury in type 2 diabetic mice.

  6. IMD-4690, a novel specific inhibitor for plasminogen activator inhibitor-1, reduces allergic airway remodeling in a mouse model of chronic asthma via regulating angiogenesis and remodeling-related mediators.

    Science.gov (United States)

    Tezuka, Toshifumi; Ogawa, Hirohisa; Azuma, Masahiko; Goto, Hisatsugu; Uehara, Hisanori; Aono, Yoshinori; Hanibuchi, Masaki; Yamaguchi, Yoichi; Fujikawa, Tomoyuki; Itai, Akiko; Nishioka, Yasuhiko

    2015-01-01

    Plasminogen activator inhibitor (PAI)-1 is the principal inhibitor of plasminogen activators, and is responsible for the degradation of fibrin and extracellular matrix. IMD-4690 is a newly synthesized inhibitor for PAI-1, whereas the effect on allergic airway inflammation and remodeling is still unclear. We examined the in vivo effects by using a chronic allergen exposure model of bronchial asthma in mice. The model was generated by an immune challenge for 8 weeks with house dust mite antigen, Dermatophagoides pteronyssinus (Dp). IMD-4690 was intraperitoneally administered during the challenge. Lung histopathology, hyperresponsiveness and the concentrations of mediators in lung homogenates were analyzed. The amount of active PAI-1 in the lungs was increased in mice treated with Dp. Administration with IMD-4690 reduced an active/total PAI-1 ratio. IMD-4690 also reduced the number of bronchial eosinophils in accordance with the decreased expressions of Th2 cytokines in the lung homogenates. Airway remodeling was inhibited by reducing subepithelial collagen deposition, smooth muscle hypertrophy, and angiogenesis. The effects of IMD-4690 were partly mediated by the regulation of TGF-β, HGF and matrix metalloproteinase. These results suggest that PAI-1 plays crucial roles in airway inflammation and remodeling, and IMD-4690, a specific PAI-1 inhibitor, may have therapeutic potential for patients with refractory asthma due to airway remodeling. PMID:25785861

  7. IMD-4690, a novel specific inhibitor for plasminogen activator inhibitor-1, reduces allergic airway remodeling in a mouse model of chronic asthma via regulating angiogenesis and remodeling-related mediators.

    Directory of Open Access Journals (Sweden)

    Toshifumi Tezuka

    Full Text Available Plasminogen activator inhibitor (PAI-1 is the principal inhibitor of plasminogen activators, and is responsible for the degradation of fibrin and extracellular matrix. IMD-4690 is a newly synthesized inhibitor for PAI-1, whereas the effect on allergic airway inflammation and remodeling is still unclear. We examined the in vivo effects by using a chronic allergen exposure model of bronchial asthma in mice. The model was generated by an immune challenge for 8 weeks with house dust mite antigen, Dermatophagoides pteronyssinus (Dp. IMD-4690 was intraperitoneally administered during the challenge. Lung histopathology, hyperresponsiveness and the concentrations of mediators in lung homogenates were analyzed. The amount of active PAI-1 in the lungs was increased in mice treated with Dp. Administration with IMD-4690 reduced an active/total PAI-1 ratio. IMD-4690 also reduced the number of bronchial eosinophils in accordance with the decreased expressions of Th2 cytokines in the lung homogenates. Airway remodeling was inhibited by reducing subepithelial collagen deposition, smooth muscle hypertrophy, and angiogenesis. The effects of IMD-4690 were partly mediated by the regulation of TGF-β, HGF and matrix metalloproteinase. These results suggest that PAI-1 plays crucial roles in airway inflammation and remodeling, and IMD-4690, a specific PAI-1 inhibitor, may have therapeutic potential for patients with refractory asthma due to airway remodeling.

  8. HIF1α deficiency reduces inflammation in a mouse model of proximal colon cancer

    Directory of Open Access Journals (Sweden)

    Dessislava N. Mladenova

    2015-09-01

    Full Text Available Hypoxia-inducible factor 1α (HIF1α is a transcription factor that regulates the adaptation of cells to hypoxic microenvironments, for example inside solid tumours. Stabilisation of HIF1α can also occur in normoxic conditions in inflamed tissue or as a result of inactivating mutations in negative regulators of HIF1α. Aberrant overexpression of HIF1α in many different cancers has led to intensive efforts to develop HIF1α-targeted therapies. However, the role of HIF1α is still poorly understood in chronic inflammation that predisposes the colon to carcinogenesis. We have previously reported that the transcription of HIF1α is upregulated and that the protein is stabilised in inflammatory lesions that are caused by the non-steroidal anti-inflammatory drug (NSAID sulindac in the mouse proximal colon. Here, we exploited this side effect of long-term sulindac administration to analyse the role of HIF1α in colon inflammation using mice with a Villin-Cre-induced deletion of Hif1α exon 2 in the intestinal epithelium (Hif1αΔIEC. We also analysed the effect of sulindac sulfide on the aryl hydrocarbon receptor (AHR pathway in vitro in colon cancer cells. Most sulindac-treated mice developed visible lesions, resembling the appearance of flat adenomas in the human colon, surrounded by macroscopically normal mucosa. Hif1αΔIEC mice still developed lesions but they were smaller than in the Hif1α-floxed siblings (Hif1αF/F. Microscopically, Hif1αΔIEC mice had significantly less severe colon inflammation than Hif1αF/F mice. Molecular analysis showed reduced MIF expression and increased E-cadherin mRNA expression in the colon of sulindac-treated Hif1αΔIEC mice. However, immunohistochemistry analysis revealed a defect of E-cadherin protein expression in sulindac-treated Hif1αΔIEC mice. Sulindac sulfide treatment in vitro upregulated Hif1α, c-JUN and IL8 expression through the AHR pathway. Taken together, HIF1α expression augments inflammation

  9. HIF1α deficiency reduces inflammation in a mouse model of proximal colon cancer.

    Science.gov (United States)

    Mladenova, Dessislava N; Dahlstrom, Jane E; Tran, Phuong N; Benthani, Fahad; Bean, Elaine G; Ng, Irvin; Pangon, Laurent; Currey, Nicola; Kohonen-Corish, Maija R J

    2015-09-01

    Hypoxia-inducible factor 1α (HIF1α) is a transcription factor that regulates the adaptation of cells to hypoxic microenvironments, for example inside solid tumours. Stabilisation of HIF1α can also occur in normoxic conditions in inflamed tissue or as a result of inactivating mutations in negative regulators of HIF1α. Aberrant overexpression of HIF1α in many different cancers has led to intensive efforts to develop HIF1α-targeted therapies. However, the role of HIF1α is still poorly understood in chronic inflammation that predisposes the colon to carcinogenesis. We have previously reported that the transcription of HIF1α is upregulated and that the protein is stabilised in inflammatory lesions that are caused by the non-steroidal anti-inflammatory drug (NSAID) sulindac in the mouse proximal colon. Here, we exploited this side effect of long-term sulindac administration to analyse the role of HIF1α in colon inflammation using mice with a Villin-Cre-induced deletion of Hif1α exon 2 in the intestinal epithelium (Hif1α(ΔIEC)). We also analysed the effect of sulindac sulfide on the aryl hydrocarbon receptor (AHR) pathway in vitro in colon cancer cells. Most sulindac-treated mice developed visible lesions, resembling the appearance of flat adenomas in the human colon, surrounded by macroscopically normal mucosa. Hif1α(ΔIEC) mice still developed lesions but they were smaller than in the Hif1α-floxed siblings (Hif1α(F/F)). Microscopically, Hif1α(ΔIEC) mice had significantly less severe colon inflammation than Hif1α(F/F) mice. Molecular analysis showed reduced MIF expression and increased E-cadherin mRNA expression in the colon of sulindac-treated Hif1α(ΔIEC) mice. However, immunohistochemistry analysis revealed a defect of E-cadherin protein expression in sulindac-treated Hif1α(ΔIEC) mice. Sulindac sulfide treatment in vitro upregulated Hif1α, c-JUN and IL8 expression through the AHR pathway. Taken together, HIF1α expression augments inflammation in

  10. The effect of dexamethasone on the radiation survival response and misonidazole-induced hypoxic-cell cytotoxicity in Chinese hamster cells V-79-753B in vitro

    International Nuclear Information System (INIS)

    Overnight exposure of Chinese hamster cells, V-79-753B, to microgram quantities of the synthetic corticosteroid, dexamethasone, resulted in a decrease in sensitivity towards radiation, both in air and in hypoxia. The effect was dose-modifying and the oxygen enhancement ratio did not change appreciably. Similarly, when dexamethasone-treated hypoxic cells were irradiated in the presence of misonidazole, a hypoxic cell radiosensitizer, there was a decrease in radiation sensitivity compared with untreated hypoxic cells irradiated with misonidazole. (author)

  11. Hypoxic preconditioning increases the protective effect of bone marrow mesenchymal stem cells on spinal cord ischemia/reperfusion injury.

    Science.gov (United States)

    Wang, Zhilin; Fang, Bo; Tan, Zhibin; Zhang, Dong; Ma, Hong

    2016-03-01

    Transplantation of bone marrow mesenchymal stem cells (BMSCs) protect against spinal cord ischemia/reperfusion injury (SCIRI). However, a large number of transplanted BMSCs often undergo apoptosis, which severely affects the treatment outcome. Previous studies have demonstrated that hypoxic preconditioning effectively increases the survival rate of BMSCs following transplantation, and increases their protective effect on injured tissues. However, there have been few reports regarding roles of hypoxic preconditioning in SCIRI. The present study isolated rat BMSCs and separately transplanted hypoxia‑ and non‑hypoxia‑preconditioned BMSCs into the spinal cord tissues of rats with SCIRI. The role of hypoxic preconditioning in the promotion of the protective effect of BMSCs on SCIRI was investigated using neurological function scores, Evans blue staining, hematoxylin and eosin staining and terminal deoxynucleotidyl transferase dUTP nick end labeling. In addition, reverse transcription‑quantitative polymerase chain reaction and western blotting were used to detect the expression levels of hypoxia‑inducible factor 1α (HIF‑1α), and to investigate its possible underlying mechanism of action. The results indicated that hypoxic preconditioning effectively increased the protective effects of BMSCs on neurological function, blood spinal cord barrier and tissue damage following SCIRI, and inhibited apoptosis. Furthermore, hypoxic preconditioned BMSCs upregulated the expression of HIF‑1α in spinal cord tissues. Therefore, hypoxic preconditioning effectively increased the protective effect of BMSCs on SCIRI and may be associated with upregulation of the expression of HIF‑1α. Hypoxic preconditioning may serve as an effective means of increasing the protective effect of BMSCs on SCIRI. PMID:26783161

  12. Hypoxia monitoring activities within the FP7 EU-project HYPOX: diverse approaches to understand a complex phenomenon

    Science.gov (United States)

    Janssen, F.; Waldmann, C.; Boetius, A.

    2012-04-01

    Hypoxic conditions in aquatic systems and the occurrence of 'dead zones' increase worldwide due to man-made eutrophication and global warming with consequences for biodiversity, ecosystem functions and services such as fisheries, aquaculture and tourism. Monitoring of hypoxia and its consequences has to (1) account for the appropriate temporal and spatial scales, (2) separate anthropogenic from natural drivers and long-term trends from natural variations, (3) assess ecosystem response, (4) use modeling tools for generalization and prediction, and (5) share data and obtained knowledge. In 2009 the EU FP7 project HYPOX (www.hypox.net) started out as a pioneering attempt to improve and integrate hypoxia observation capacities addressing these requirements. Target ecosystems selected for HYPOX cover a broad range of settings (e.g., hydrography, oxygenation status, biological activity, anthropogenic impact) and differ in their sensitivity towards change. Semi-enclosed basins with permanent anoxia (Black Sea, Baltic Sea), are included as well as seasonally or locally hypoxic land-locked systems (fjords, lagoons, lakes) and open ocean systems with high sensitivity to global warming (North Atlantic - Arctic transition). Adopted monitoring approaches involve autonomous, cabled, and shipboard instruments and include static and profiling moorings, benthic observatories, drifters, as well as classical CTD surveys. In order to improve observatory performance, project activities encompass developments of oxygen sensors as well as calibration procedures and technologies to reduce biofouling. Modeling and data assimilation are used to synthesize findings, to obtain an in-depth understanding of hypoxia causes and consequences, and to improve forecasting capacities. For integration of the collected information into a global oxygen observing system, results are disseminated through the HYPOX portal following GEOSS data sharing principles. This presentation will give an overview of

  13. Interaction of caveolin-1, nitric oxide, and nitric oxide synthases in hypoxic human SK-N-MC neuroblastoma cells.

    Science.gov (United States)

    Shen, Jiangang; Lee, Waisin; Li, Yue; Lau, Chi Fai; Ng, Kwong Man; Fung, Man Lung; Liu, Ke Jian

    2008-10-01

    Neuroblastoma cells are capable of hypoxic adaptation, but the mechanisms involved are not fully understood. We hypothesized that caveolin-1 (cav-1), a plasma membrane signal molecule, might play a role in protecting neuroblastoma cells from oxidative injury by modulating nitric oxide (NO) production. We investigated the alterations of cav-1, cav-2, nitric oxide synthases (NOS), and NO levels in human SK-N-MC neuroblastoma cells exposed to hypoxia with 2% [O2]. The major discoveries include: (i) cav-1 but not cav-2 was up-regulated in the cells exposed to 15 h of hypoxia; (ii) NO donor 1-[N, N-di-(2-aminoethyl) amino] diazen-1-ium-1, 2-diolate up-regulated the expression of cav-1, whereas the non-selective NOS inhibitor N(G)-nitro-L-arginine methyl ester and inducible NOS (iNOS) inhibitor 1400W each abolished the increase in cav-1 expression in the hypoxic SK-N-MC cells. These results suggest that iNOS-induced NO production contributes to the up-regulation of cav-1 in the hypoxic SK-N-MC cells. Furthermore, we studied the roles played by cav-1 in regulating NO, NOS, and apoptotic cell death in the SK-N-MC cells subjected to 15 h of hypoxic treatment. Both cav-1 transfection and cav-1 scaffolding domain peptide abolished the induction of iNOS, reduced the production of NO, and reduced the rates of apoptotic cell death in the hypoxic SK-N-MC cells. These results suggest that increased expression of cav-1 in response to hypoxic stimulation could prevent oxidative injury induced by reactive oxygen species. The interactions of cav-1, NO, and NOS could be an important signal pathway in protecting the neuroblastoma cells from oxidative injury, contributing to the hypoxic tolerance of neuroblastoma cells. PMID:18717816

  14. Connexin 43 Suppresses Tumor Angiogenesis by Down-Regulation of Vascular Endothelial Growth Factor via Hypoxic-Induced Factor-1α

    Directory of Open Access Journals (Sweden)

    Wei-Kuang Wang

    2014-12-01

    Full Text Available Previous work showed that connexin 43 (Cx43 reduced the expression of hypoxic-induced factor-1α (HIF-1α in astrocytes. HIF-1α is a master transcription factor for angiogenesis in tumor. Angiogenesis is essential for tumor progression. Here, we investigated the role of Cx43 in vascular endothelial growth factor (VEGF production and angiogenesis in murine tumor. In the study, mouse B16F10 and 4T1 cells were overexpressed or knockdown with Cx43. The expression profiles as well as activity of the treated cells were examined. Furthermore, reduced Cx43 expression in B16F10 and 4T1 cells causes increased expression of VEGF and enhanced the proliferation of endothelial cells. On the contrary, the expression of VEGF and the proliferation of endothelial were increased in the conditioned medium of Cx43-knockdown tumor cells. We subcutaneously transplanted Cx43-overexpressing B16F10 cells into mice to evaluate the roles of Cx43 in the tumor angiogenesis. Both tumor size and the number of vessels growing in the tumor were markedly decreased compare with control group. Our findings suggest that Cx43 inhibited tumor growth by reducing angiogenesis.

  15. Genetic and hypoxic alterations of the microRNA-210-ISCU1/2 axis promote iron–sulfur deficiency and pulmonary hypertension

    Science.gov (United States)

    White, Kevin; Lu, Yu; Annis, Sofia; Hale, Andrew E; Chau, B Nelson; Dahlman, James E; Hemann, Craig; Opotowsky, Alexander R; Vargas, Sara O; Rosas, Ivan; Perrella, Mark A; Osorio, Juan C; Haley, Kathleen J; Graham, Brian B; Kumar, Rahul; Saggar, Rajan; Saggar, Rajeev; Wallace, W Dean; Ross, David J; Khan, Omar F; Bader, Andrew; Gochuico, Bernadette R; Matar, Majed; Polach, Kevin; Johannessen, Nicolai M; Prosser, Haydn M; Anderson, Daniel G; Langer, Robert; Zweier, Jay L; Bindoff, Laurence A; Systrom, David; Waxman, Aaron B; Jin, Richard C; Chan, Stephen Y

    2015-01-01

    Iron–sulfur (Fe-S) clusters are essential for mitochondrial metabolism, but their regulation in pulmonary hypertension (PH) remains enigmatic. We demonstrate that alterations of the miR-210-ISCU1/2 axis cause Fe-S deficiencies in vivo and promote PH. In pulmonary vascular cells and particularly endothelium, hypoxic induction of miR-210 and repression of the miR-210 targets ISCU1/2 down-regulated Fe-S levels. In mouse and human vascular and endothelial tissue affected by PH, miR-210 was elevated accompanied by decreased ISCU1/2 and Fe-S integrity. In mice, miR-210 repressed ISCU1/2 and promoted PH. Mice deficient in miR-210, via genetic/pharmacologic means or via an endothelial-specific manner, displayed increased ISCU1/2 and were resistant to Fe-S-dependent pathophenotypes and PH. Similar to hypoxia or miR-210 overexpression, ISCU1/2 knockdown also promoted PH. Finally, cardiopulmonary exercise testing of a woman with homozygous ISCU mutations revealed exercise-induced pulmonary vascular dysfunction. Thus, driven by acquired (hypoxia) or genetic causes, the miR-210-ISCU1/2 regulatory axis is a pathogenic lynchpin causing Fe-S deficiency and PH. These findings carry broad translational implications for defining the metabolic origins of PH and potentially other metabolic diseases sharing similar underpinnings. PMID:25825391

  16. Nitric oxide production by polymorphonuclear leukocytes in sputum from cystic fibrosis patients with chronic lung infection

    DEFF Research Database (Denmark)

    Kolpen, Mette; Bjarnsholt, Thomas; Moser, Claus;

    2010-01-01

    Objective: Chronic Pseudomonas aeruginosa lung infection in CF patients is characterized by persisting mucoid biofilm in hypoxic endobronchial mucus. These biofilms are surrounded by numerous polymorphonuclear leukocytes (PMNs), which are the major consumers of O2 for production of O2-. In this s...

  17. Chronic myelogenous leukemia (CML)

    Science.gov (United States)

    CML; Chronic myeloid leukemia; Chronic granulocytic leukemia; Leukemia - chronic granulocytic ... nuclear disaster. It takes many years to develop leukemia from radiation exposure. Most people treated for cancer ...

  18. Chronic obstructive pulmonary disease

    Science.gov (United States)

    ... airways disease; Chronic obstructive lung disease; Chronic bronchitis; Emphysema; Bronchitis - chronic ... a protein called alpha-1 antitrypsin can develop emphysema. Other risk factors for COPD are: Exposure to ...

  19. β-adrenergic response modulated by κ-opioid receptor stimulation is attenuated in the cardiomyocytes of rats following chronic hypoxia

    Institute of Scientific and Technical Information of China (English)

    裴建明; 毕辉; 王跃民; 朱妙章; 周京军; 朱运龙

    2003-01-01

    Objective: To study cross-talk between β-opioid receptor and β-adrenoceptor through determination of the intracellular calcium ([Ca2+]i) and cAMP responses in ventricular myocytes of rats subjected to chronic hypoxia for 4 weeks.Methods: Electrically-induced [Ca2+]i transient was measured in single right ventricular myocytes isolated from hearts of chronically hypoxic rats and the age-matched normoxic rats, by using a spectrofluorometric method.Results: β-adrenoceptor stimulation with isoproterenol increased the electrically-induced [Ca2+]i transient and cAMP in myocytes of normoxic rats.U50,488H, a selective β-opioid receptor agonist, at dose (1 μmol/L) which itself had no effect on the [Ca2+]i transient and cAMP, significantly inhibited the effect of isoproterenol.This inhibition was completely abolished in the presence of nor-BNI, a selective κ-opioid receptor antagonist.In the ventricular myocytes of chronically hypoxic rats, the inhibition of U50,488H on the increased [Ca2+]i transient and cAMP with isoproterenol was blunted.Conclusion: Results indicate that the cross-talk between the κ-opioid receptor and β-adrenoceptor is attenuated in the right ventricular myocytes of chronically hypoxic rat.This may be a self-protective mechanism of the heart following chronic hypoxia, which prevents the further decrease of the cardiac function.

  20. Mouse Phenome Database (MPD)

    Data.gov (United States)

    U.S. Department of Health & Human Services — The Mouse Phenome Database (MPD) has characterizations of hundreds of strains of laboratory mice to facilitate translational discoveries and to assist in selection...

  1. Mouse Genome Informatics (MGI)

    Data.gov (United States)

    U.S. Department of Health & Human Services — MGI is the international database resource for the laboratory mouse, providing integrated genetic, genomic, and biological data to facilitate the study of human...

  2. 低氧运动/训练研究新动向%New Trends of the Hypoxic Exercises/Trainings

    Institute of Scientific and Technical Information of China (English)

    王茹

    2012-01-01

    低氧训练与竞技能力提高、与健康有关的问题一直是国际运动科学的研究热点。以2012年第59届美国运动医学会年会交流论文为例,低氧训练/低氧运动为主题,从低氧运动在健康促进中的研究与应用、低氧训练促进竞技水平研究中的新发现、低氧运动/训练机制研究新进展、低氧运动中的营养补充等四个方面进行综述。2012年ACSM大会上低氧运动研究涉及医学、航天,体育等领域,人们对其研究涉及诸多内容,低氧运动形式各自存在着相应的适用范围及优缺点,采取有效措施扬长避短发挥低氧运动优势,促进潜能发挥,是本次大会低氧运动的核心理念。%Hypoxic training issues relating to the enhancement of competitiveness and health have always been a hot topic of the international sports science.The paper uses the papers published in the 59th America College of Sports Medicine in 2012 as the example,focused on the topic of the hypoxic training/hypoxic exercises to make a review from four perspectives,namely,the research and application of the hypoxic exercises in the promotion of health,the new findings in the enhancing effect of hypoxic training in competitiveness,new development in the research of the hypoxic exercises/training mechanism and the nutrition supplement of the hypoxic exercises.The academic researches reported in the ACSM meeting in 2012 relate to the field of medicine,aviation and sports.The researches cover a wide range of topics.Different forms of hypoxic exercises have corresponding application scope,advantages and disadvantages.The core notion of the hypoxic exercise research in the meeting is to adopt effective measures to develop its advantages while avoid its disadvantages and promote the display of its potential.

  3. The autophagy associated gene, ULK1, promotes tolerance to chronic and acute hypoxia

    International Nuclear Information System (INIS)

    Background and purpose: Tumor hypoxia is associated with therapy resistance and malignancy. Previously we demonstrated that activation of autophagy and the unfolded protein response (UPR) promote hypoxia tolerance. Here we explored the importance of ULK1 in hypoxia tolerance, autophagy induction and its prognostic value for recurrence after treatment. Material and methods: Hypoxic regulation of ULK1 mRNA and protein was assessed in vitro and in primary human head and neck squamous cell carcinoma (HNSCC) xenografts. Its importance in autophagy induction, mitochondrial homeostasis and tolerance to chronic and acute hypoxia was evaluated in ULK1 knockdown cells. The prognostic value of ULK1 mRNA expression was assessed in 82 HNSCC patients. Results: ULK1 enrichment was observed in hypoxic tumor regions. High enrichment was associated with a high hypoxic fraction. In line with these findings, high ULK1 expression in HNSCC patients appeared associated with poor local control. Exposure of cells to hypoxia induced ULK1 mRNA in a UPR and HIF1α dependent manner. ULK1 knockdown decreased autophagy activation, increased mitochondrial mass and ROS exposure and sensitized cells to acute and chronic hypoxia. Conclusions: We demonstrate that ULK1 is a hypoxia regulated gene and is associated with hypoxia tolerance and a worse clinical outcome

  4. Enhanced phosphorylation of cyclic AMP response element binding protein in Brain of mice following repetitive hypoxic exposure

    International Nuclear Information System (INIS)

    Cerebral ischemic/hypoxic preconditioning (I/HPC) is a phenomenon of endogenous protection that renders Brain tolerant to sustained ischemia/hypoxia. This profound protection induced by I/HPC makes it an attractive target for developing potential clinical therapeutic approaches. However, the molecular mechanism of I/HPC is unclear. Cyclic AMP (cAMP) response element binding protein (CREB), a selective nuclear transcriptional factor, plays a key role in the neuronal functions. Phosphorylation of CREB on Ser-133 may facilitate its transcriptional activity in response to various stresses. In the current study, we observed the changes in CREB phosphorylation (Ser-133) and protein expression in Brain of auto-hypoxia-induced HPC mice by using Western blot analysis. We found that the levels of phosphorylated CREB (Ser-133), but not protein expression of CREB, increased significantly (p < 0.05) in the hippocampus and the frontal cortex of mice after repetitive hypoxic exposure (H2-H4, n = 6 for each group), when compared to that of the normoxic (H0, n = 6) or hypoxic exposure once group (H1, n = 6). In addition, a significant enhancement (p < 0.05) of CREB phosphorylation (Ser-133) could also be found in the nuclear extracts from the whole hippocampus of hypoxic preconditioned mice (H2-H4, n = 6 for each group). These results suggest that the phosphorylation of CREB might be involved in the development of cerebral hypoxic preconditioning

  5. Porfiromycin as a bioreductive alkylating agent with selective toxicity to hypoxic EMT6 tumor cells in vivo and in vitro.

    Science.gov (United States)

    Keyes, S R; Rockwell, S; Sartorelli, A C

    1985-08-01

    Hypoxic cells may limit the curability of solid tumors by conventional chemotherapeutic agents and radiotherapy. Agents which are preferentially toxic to cells with low oxygen contents could therefore be useful as adjuncts to the regimens now used to treat these cancers. To date, the best agent of this type that we have tested is porfiromycin. Porfiromycin is similar to mitomycin C in its toxicity to hypoxic EMT6 cells in vitro but has much less toxicity than mitomycin C to well-oxygenated EMT6 cells. EMT6 cell sonicates reduce mitomycin C and porfiromycin to reactive electrophiles at similar rates under hypoxic conditions, a finding that correlates with cytotoxicity, whereas the rate of production of reactive species from both drugs is very slow under aerobic conditions. We also show that porfiromycin is capable of killing hypoxic radiation-resistant cells in solid EMT6 tumors. Appropriate regimens combining porfiromycin (which preferentially kills hypoxic cells) and radiation (which preferentially kills aerated cells) may therefore be especially efficacious for the treatment of solid tumors. PMID:3926306

  6. 慢性束缚应激小鼠海马神经元5-羟色胺1A受体表达的变化%Change in the expression of hippocampal neuronal 5-hyroxytryptamine1A receptor in a mouse model of chronic restraint stress

    Institute of Scientific and Technical Information of China (English)

    宛春甫; 刘玉华; 李志华; 薛中会

    2011-01-01

    Objective To investigate the change in expression of hippocampal neuronal 5-hyroxytryptamine1A(5-HT1A) receptor in a mouse model of chronic restraint stress.Methods Forty BALB/c male mice aged 6-9 months weighing 25-35 g were randomly divided into 2 groups ( n =20 each): normal control group (group C) and chronic restraint stress group( group S).In group S,the model of chronic restraint stress was established described by Wood et al.Tail suspension test,light-dark test and Morris water maze test were performed respectively at 1 d after successful establishment of the model.Immobility time,staying time in light compartment,and escape latency and frequency of crossing the original platform were recorded respectively in tail suspension test,light-dark test and Morris water maze test.Then the animals were sacrificed,hippocampi were removed for determination of the expression of 5-HT1A receptor in CA1 and CA3 regions of hippocampal neurons by immuno-histochemistry.Results Compared with group C,immobility time and escape latency were significantly prolonged,staying time in light compartment was shortened,frequency of crossing the original platform was decreased,and the expression of 5-HT1A receptor in hippocampal neurons was down-regulated in group S ( P < 0.05 or 0.01 ).Conclusion Chronic restraint stress can induce cognitive impairment in mice by down-regulating the expression of 5-HT1A receptor in hippocampal neurons.%目的 探讨慢性束缚应激小鼠海马神经元5-羟色胺1A(5-HT1A)受体表达的变化.方法 BALB/c种系雄性小鼠40只,6~9月龄,体重25~35 g,采用随机数字表法,将其随机分为2组(n=20):正常对照组(C组)和慢性束缚应激组(S组).S组慢性束缚应激模型制备成功后1d,依次进行悬尾实验、明暗穿箱实验和水迷宫实验,悬尾实验中记录静止时间,明暗穿箱实验中记录明亮箱中停留时间,水迷宫实验中记录逃避潜伏期和穿过平台次数.然后处死小鼠,取海马组

  7. Characteristics of fat metabolism in skeletal muscle of rats after hypobaric hypoxic acclimation

    Institute of Scientific and Technical Information of China (English)

    Mao Sunzhong; Gao Yuqi; Chen Jian; Liu Fuyi; Gao Wenxiang; Huang Jian; Liao Weigong; Cai Mingchun

    2008-01-01

    Objective: To investigate the characteristics of fat metabolism in rat skeletal muscle after hypobaric hypoxia acclimation. Methods: Sprague-Dawley rats were divided into 3 groups randomly: control group (H0), hypoxic 5-day group (H5), and hypoxic 15-day group (HI5). Animals of H5 and 15 groups were exposed to hypobaric hypoxia chamber simulating 5 000 m high altitude for 5 d or 15 d respectively, 23 h per day. H0 group stayed outside of chamber.The level of fatty acid oxidation and uptake, and glucose oxidation were examined, and the level of non-esterified fatty acids (NEFA), ATP and phosphocreatine (PCr) were also assayed in rat skeletal muscles. Results: The contents of ATP and PCr in H5 group were lower than those in H0 and H15 groups (P<0.05), while there was no significant difference between H0 and H15. Compared with H0, the blood NEFA level in all hypoxia groups was increased significantly (P<0.05). The muscle NEFA level in HI5 group was greatly higher than that in H0 and H5 groups. The rates of fatty acid oxidation and uptake in H15 group were significantly higher than those in H0 and H5 groups (P<0.05), and the rate of glucose oxidation in all hypoxia groups was significantly decreased than that in H0 group (P<0.05). Conclusion: It is concluded that the enhanced fat oxidation may be one of the mechanisms in the maintenance of energy homeostasis after hypobaric hypoxic acclimation.

  8. Chick embryos have the same pattern of hypoxic lower-brain activation as fetal mammals.

    Science.gov (United States)

    Landry, Jeremy P; Hawkins, Connor; Lee, Aaron; Coté, Alexandra; Balaban, Evan; Pompeiano, Maria

    2016-01-01

    cFos expression (indicating a particular kind of neuronal activation) was examined in embryonic day (E) 18 chick embryos after exposure to 4 h of either normoxia (21% O2), modest hypoxia (15% O2), or medium hypoxia (10% O2). Eight regions of the brainstem and hypothalamus were surveyed, including seven previously shown to respond to hypoxia in late-gestation mammalian fetuses (Breen et al., 1997; Nitsos and Walker, 1999b). Hypoxia-related changes in chick embryo brain activation mirrored those found in fetal mammals with the exception of the medullary Raphe, which showed decreased hypoxic activation, compared with no change in mammals. This difference may be explained by the greater anapyrexic responses of chick embryos relative to mammalian fetuses. Activation in the A1/C1 region was examined in more detail to ascertain whether an O2-sensitive subpopulation of these cells containing heme oxygenase 2 (HMOX2) may drive hypoxic brain responses before the maturation of peripheral O2-sensing. HMOX2-positive and -negative catecholaminergic cells and interdigitating noncatecholaminergic HMOX2-positive cells all showed significant changes in cFos expression to hypoxia, with larger population responses seen in the catecholaminergic cells. Hypoxia-induced activation of lower-brain regions studied here was significantly better correlated with activation of the nucleus of the solitary tract (NTS) than with that of HMOX2-containing A1/C1 neurons. Together, these observations suggest that (1) the functional circuitry controlling prenatal brain responses to hypoxia is strongly conserved between birds and mammals, and (2) NTS neurons are a more dominant driving force for prenatal hypoxic cFos brain responses than O2-sensing A1/C1 neurons.

  9. Long lasting local and systemic inflammation after cerebral hypoxic ischemia in newborn mice.

    Directory of Open Access Journals (Sweden)

    Max Winerdal

    Full Text Available BACKGROUND: Hypoxic ischemia (HI is an important cause of neonatal brain injury and subsequent inflammation affects neurological outcome. In this study we performed investigations of systemic and local activation states of inflammatory cells from innate and adaptive immunity at different time points after neonatal HI brain injury in mice. METHODOLOGY/PRINCIPAL FINDINGS: We developed a multiplex flow cytometry based method combined with immunohistochemistry to investigate cellular immune responses in the brain 24 h to 7 months after HI brain injury. In addition, functional studies of ex vivo splenocytes after cerebral hypoxic ischemia were performed. Both central and peripheral activation of CD11b(+ and CD11c(+ antigen presenting cells were seen with expression of the costimulatory molecule CD86 and MHC-II, indicating active antigen presentation in the damaged hemisphere and in the spleen. After one week, naïve CD45rb(+ T-lymphocytes were demonstrated in the damaged brain hemisphere. In a second phase after three months, pronounced activation of CD45rb(- T-lymphocytes expressing CD69 and CD25 was seen in the damaged hemisphere. Brain homogenate induced proliferation in splenocytes after HI but not in controls. CONCLUSIONS/SIGNIFICANCE: Our findings demonstrate activation of both local and systemic immune responses months after hypoxic ischemic neonatal brain injury. The long term immune activation observed is of general importance for future studies of the inflammatory response after brain injury as most previous studies have focused on the first few weeks after damage, while the effects of the late inflammation phase may be missed. Furthermore, the self-reactive component raises the question if there is a correlation with development of autoimmune brain disease later in life.

  10. Biogeochemical processes and buffering capacity concurrently affect acidification in a seasonally hypoxic coastal marine basin

    Directory of Open Access Journals (Sweden)

    M. Hagens

    2014-11-01

    Full Text Available Coastal areas are impacted by multiple natural and anthropogenic processes and experience stronger pH fluctuations than the open ocean. These variations can weaken or intensify the ocean acidification signal induced by increasing atmospheric pCO2. The development of eutrophication-induced hypoxia intensifies coastal acidification, since the CO2 produced during respiration decreases the buffering capacity of the hypoxic bottom water. To assess the combined ecosystem impacts of acidification and hypoxia, we quantified the seasonal variation in pH and oxygen dynamics in the water column of a seasonally stratified coastal basin (Lake Grevelingen, the Netherlands. Monthly water column chemistry measurements were complemented with estimates of primary production and respiration using O2 light-dark incubations, in addition to sediment-water fluxes of dissolved inorganic carbon (DIC and total alkalinity (TA. The resulting dataset was used to set up a proton budget on a seasonal scale. Temperature-induced seasonal stratification combined with a high community respiration was responsible for the depletion of oxygen in the bottom water in summer. The surface water showed strong seasonal variation in process rates (primary production, CO2 air–sea exchange, but relatively small seasonal pH fluctuations (0.46 units on the total hydrogen ion scale. In contrast, the bottom water showed less seasonality in biogeochemical rates (respiration, sediment–water exchange, but stronger pH fluctuations (0.60 units. This marked difference in pH dynamics could be attributed to a substantial reduction in the acid-base buffering capacity of the hypoxic bottom water in the summer period. Our results highlight the importance of acid-base buffering in the pH dynamics of coastal systems and illustrate the increasing vulnerability of hypoxic, CO2-rich waters to any acidifying process.

  11. Effects of hypercapnia and NO synthase inhibition in sustained hypoxic pulmonary vasoconstriction

    Directory of Open Access Journals (Sweden)

    Ketabchi Farzaneh

    2012-01-01

    Full Text Available Abstract Background Acute respiratory disorders may lead to sustained alveolar hypoxia with hypercapnia resulting in impaired pulmonary gas exchange. Hypoxic pulmonary vasoconstriction (HPV optimizes gas exchange during local acute (0-30 min, as well as sustained (> 30 min hypoxia by matching blood perfusion to alveolar ventilation. Hypercapnia with acidosis improves pulmonary gas exchange in repetitive conditions of acute hypoxia by potentiating HPV and preventing pulmonary endothelial dysfunction. This study investigated, if the beneficial effects of hypercapnia with acidosis are preserved during sustained hypoxia as it occurs, e.g in permissive hypercapnic ventilation in intensive care units. Furthermore, the effects of NO synthase inhibitors under such conditions were examined. Method We employed isolated perfused and ventilated rabbit lungs to determine the influence of hypercapnia with or without acidosis (pH corrected with sodium bicarbonate, and inhibitors of endothelial as well as inducible NO synthase on acute or sustained HPV (180 min and endothelial permeability. Results In hypercapnic acidosis, HPV was intensified in sustained hypoxia, in contrast to hypercapnia without acidosis when HPV was amplified during both phases. L-NG-Nitroarginine (L-NNA, a non-selective NO synthase inhibitor, enhanced acute as well as sustained HPV under all conditions, however, the amplification of sustained HPV induced by hypercapnia with or without acidosis compared to normocapnia disappeared. In contrast 1400 W, a selective inhibitor of inducible NO synthase (iNOS, decreased HPV in normocapnia and hypercapnia without acidosis at late time points of sustained HPV and selectively reversed the amplification of sustained HPV during hypercapnia without acidosis. Hypoxic hypercapnia without acidosis increased capillary filtration coefficient (Kfc. This increase disappeared after administration of 1400 W. Conclusion Hypercapnia with and without acidosis

  12. Variability on the Hypoxic Conditions in the Northwestern Region of the Baja California Peninsula

    Science.gov (United States)

    Bustos-Serrano, H.

    2015-12-01

    The NW region of the Baja California peninsula in México is dominated by the California Current System (CCS). Dissolved oxygen (DO) is a key variable in water bodies because it is considered as a health in biological processes. Hypoxic conditions (DO 60 to 120 μmol kg-1) occur naturally in large areas of the ocean. In the Eastern Pacific, the DO can be altered by eutrophication, derived from anthropogenic activity, especially in shallow and enclosed seas. Fluctuations in the conditions of hypoxia zones may have significant ecological and economic impact. It is of interest in assessing whether hypoxic conditions in the vicinity of Bahia de Todos Santos (BTS) and Coronado Islands in México are altered by anthropogenic activity (Figs. 1 and 2 respectively). For the present study, we worked with data collected from oceanographic expeditions during the period October 2010 to June 2015. The DO was determined using a CTD (SBE Model 25) and by sea water collection with hydrographic bottles using a modification of the Winkler method. The signs of hypoxia are evident in the area near BTS and in the vicinity of Coronado´s Islands, mainly on locations between the Todos Santos Islands and the peninsula of Punta Banda, which shows that the hypoxic zone begins to occur in shallow water between 50-200 m depth. This particular area corresponds to the point where the Mexican Navy determined as a site for dredging materials from the ports of Ensenada and El Sauzal, it is possible that the anthropogenic activity alters the natural conditions of hypoxia in the area to enlarge. In June 2012 for the first time in that region we obtained sediment samples below 700 m depth, which are mixed terrigenous clastic and oceanic sediments.

  13. Impairment of mitochondrial β-oxidation in rats under cold-hypoxic environment

    Science.gov (United States)

    Dutta, Arkadeb; Vats, Praveen; Singh, Vijay K.; Sharma, Yogendra K.; Singh, Som N.; Singh, Shashi B.

    2009-09-01

    Mitochondrial ß-oxidation of fatty acid provides a major source of energy in mammals. High altitude (HA), characterized by hypobaric hypoxia and low ambient temperatures, causes alteration in metabolic homeostasis. Several studies have depicted that hypoxic exposure in small mammals causes hypothermia due to hypometabolic state. Moreover, cold exposure along with hypoxia reduces hypoxia tolerance in animals. The present study investigated the rate of β-oxidation and key enzymes, carnitine palmitoyl transferase-I (CPT-I) and hydroxyacyl CoA dehydrogenase (HAD), in rats exposed to cold-hypobaric hypoxic environment. Male Sprague Dawley rats (190-220 g) were randomly divided into eight groups ( n = 6 rats in each group): 1 day hypoxia (H1); 7 days hypoxia (H7); 1 day cold (C1); 7 days cold (C7); 1 day cold-hypoxia (CH1); 7 days cold-hypoxia (CH7) exposed; and unexposed control for 1 and 7 days (UC1 and UC7). After exposure, animals were anaesthetized with ketamine (50 mg/kg body weight) and xylazine (10 mg/kg body weight) intraperitonialy and sacrificed. Mitochondrial CPT-I, HAD, 14C-palmitate oxidation in gastrocnemius muscle and liver, and plasma leptin were measured. Mitochondrial CPT-I was significantly reduced in muscle and liver in CH1 and CH7 as compared to respective controls. HAD activity was significantly reduced in H1 and CH7, and in H1, H7, CH1, and CH7 as compared to unexposed controls in muscle and liver, respectively. A concomitant decrease in 14C-palmitate oxidation was found. Significant reduction in plasma leptin in hypoxia and cold-hypoxia suggested hypometabolic state. It can be concluded that ß-oxidation of fatty acids is reduced in rats exposed to cold-hypoxic environment due to the persisting hypometabolic state in cold-hypoxia exposure.

  14. Nebulization of the acidified sodium nitrite formulation attenuates acute hypoxic pulmonary vasoconstriction

    Directory of Open Access Journals (Sweden)

    Surber Mark W

    2010-06-01

    Full Text Available Abstract Background Generalized hypoxic pulmonary vasoconstriction (HPV occurring during exposure to hypoxia is a detrimental process resulting in an increase in lung vascular resistance. Nebulization of sodium nitrite has been shown to inhibit HPV. The aim of this project was to investigate and compare the effects of nebulization of nitrite and different formulations of acidified sodium nitrite on acute HPV. Methods Ex vivo isolated rabbit lungs perfused with erythrocytes in Krebs-Henseleit buffer (adjusted to 10% hematocrit and in vivo anesthetized catheterized rabbits were challenged with periods of hypoxic ventilation alternating with periods of normoxic ventilation. After baseline hypoxic challenges, vehicle, sodium nitrite or acidified sodium nitrite was delivered via nebulization. In the ex vivo model, pulmonary arterial pressure and nitric oxide concentrations in exhaled gas were monitored. Nitrite and nitrite/nitrate were measured in samples of perfusion buffer. Pulmonary arterial pressure, systemic arterial pressure, cardiac output and blood gases were monitored in the in vivo model. Results In the ex vivo model, nitrite nebulization attenuated HPV and increased nitric oxide concentrations in exhaled gas and nitrite concentrations in the perfusate. The acidified forms of sodium nitrite induced higher levels of nitric oxide in exhaled gas and had longer vasodilating effects compared to nitrite alone. All nitrite formulations increased concentrations of circulating nitrite to the same degree. In the in vivo model, inhaled nitrite inhibited HPV, while pulmonary arterial pressure, cardiac output and blood gases were not affected. All nitrite formulations had similar potency to inhibit HPV. The tested concentration of appeared tolerable. Conclusion Nitrite alone and in acidified forms effectively and similarly attenuates HPV. However, acidified nitrite formulations induce a more pronounced increase in nitric oxide exhalation.

  15. Effects of Graded Hypothermia on Hypoxic-ischemic Brain Damage in the Neonatal Rat

    Institute of Scientific and Technical Information of China (English)

    Xiao-yan Xia; Yi-xin Xia

    2011-01-01

    Objective To investigate the effect of graded hypothermia on neuropathologic alteratiors of neonatal rat brain after exposed to hypoxic-ischemic insult at 37℃, 33℃, 31℃, and 28℃, respectively, and to observe the effect of hypothermia on 72-kDa heat shock protein (HSP72) expression after hypoxic-ischemic insult. Methods Seven days old Wistar rats were subjected to unilateral common carotid artery ligation followed by exposure to hypoxia in 8% oxygen for 2 hours at 37℃, 33℃, 31℃, and 28℃, respectively. The brain temperature was monitored indirectly by inserting a mini-thermocouple probe into the temporal muscle during hypoxia. After hypoxia-ischemia their mortality was assessed. Neuronal damage was assessed with HE staining 72 hours after hypoxia. HSP72 expression at 0.5, 24, and 72 hours of recovery was immunohistochemically assessed using a monoclonal antibody to HSP72. Results Hypoxia-ischemia caused 10.5% (2/19) of mortality in rat of 37℃ group, but no death occurred in 33℃, 31℃ or 28℃ groups. HE staining showed neuropathologic damage was extensive in rats exposed to hypoxia-ischemia at 37℃ (more than 80.0%). The incidence of severe brain damage was significantly decreased in 33℃ (53.3%) and 31℃ groups (44.4%), and no histologic injury was seen in the 28℃ group of rats. Expression of HSP72 was manifest and persistent in the rat brain of 37℃ group, but minimum in the rat brain of 28℃ group. Conclusion Mild and moderate hypothermia might prevent cerebral visible neuropathologic damage associated with hypoxic-ischemic injury by decreasing stress response.

  16. Chronic pain - resources

    Science.gov (United States)

    Pain - resources; Resources - chronic pain ... The following organizations are good resources for information on chronic pain: American Chronic Pain Association -- www.theacpa.org National Fibromyalgia and Chronic Pain Association -- www.fmcpaware.org ...

  17. Low back pain - chronic

    Science.gov (United States)

    Nonspecific back pain; Backache - chronic; Lumbar pain - chronic; Pain - back - chronic; Chronic back pain - low ... Low back pain is common. Almost everyone has back pain at some time in their life. Often, the exact cause ...

  18. Chronic motor tic disorder

    Science.gov (United States)

    Chronic vocal tic disorder; Tic - chronic motor tic disorder ... Chronic motor tic disorder is more common than Tourette syndrome . Chronic tics may be forms of Tourette syndrome. Tics usually start ...

  19. Chronic Pelvic Pain

    Science.gov (United States)

    ... Events Advocacy For Patients About ACOG Chronic Pelvic Pain Home For Patients Search FAQs Chronic Pelvic Pain ... Pain FAQ099, August 2011 PDF Format Chronic Pelvic Pain Gynecologic Problems What is chronic pelvic pain? What ...

  20. Employees with Chronic Pain

    Science.gov (United States)

    ... Home | Accommodation and Compliance Series: Employees with Chronic Pain By Beth Loy, Ph.D. Preface Introduction Information ... at http://AskJAN.org/soar. Information about Chronic Pain How prevalent is chronic pain? Chronic pain has ...