Rudolf Moldzio

University of Veterinary Medicine in Vienna, Wien, Vienna, Austria

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Publications (26)69.01 Total impact

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    ABSTRACT: Phytocannabinoids are potentially candidates for neurodegenerative disease treatment. Nonetheless, the exact mode of action of major phytocannabinoids has to be elucidated, but both, receptor and non-receptor mediated effects are discussed. Focusing on the often presumed structure-affinity-relationship, Ki values of phytocannabinoids cannabidiol (CBD), cannabidivarin (CBDV), cannabichromene (CBC), cannabigerol (CBG), cannabinol (CBN), THC acid (THCA) and THC to human CB1 and CB2 receptors were detected by using competitive inhibition between radioligand [3H]CP-55,940 and the phytocannabinoids. Resulting Ki values to CB1 range from 23.5 μM (THCA) to 14711 μM (CBDV), whereas Ki values to CB2 range from 8.5 μM (THC) to 574.2 μM (CBDV). To study the relationship between binding affinity and effects on neurons, we investigated possible CB1 related cytotoxic properties in murine mesencephalic primary cell cultures and N18TG2 neuroblastoma cell line. Most of the phytocannabinoids did not affect the number of dopaminergic neurons in primary cultures, whereas propidium iodide and resazurin formation assays revealed cytotoxic properties of CBN, CBDV and CBG. However, THC showed positive effects on N18TG2 cell viability at a concentration of 10 μM, whereas also CBC and THCA displayed slightly positive activities. These findings are neither linked to structural characteristics nor to the receptor binding affinity therewith pointing to another mechanism than a receptor mediated one.
    Neurotoxicology and Teratology 10/2014; · 3.18 Impact Factor
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    ABSTRACT: Tocopherols (TOH) are lipophilic antioxidants which require the phenolic OH group for their redox activity. In contrast, non-redox active esters of α-TOH with succinate (α-TOS) were shown to possess proapoptotic activity in cancer cells. It was suggested that this activity is mediated via mitochondrial inhibition with subsequent O2(-) production triggering apoptosis and that the modification of the linker between the succinate and the lipophilic chroman may modulate this activity. However, the specific mechanism and the influence of the linker are not clear yet on the level of the mitochondrial respiratory chain. Therefore, this study systematically compared the effects of α-TOH acetate (α-TOA), α-TOS and α-tocopheramine succinate (α-TNS) in cells and submitochondrial particles (SMP). The results showed that not all cancer cell lines are highly sensitive to α-TOS and α-TNS. In HeLa cells α-TNS did more effectively reduce cell viability than α-TOS. The complex I activity of SMP was little affected by α-TNS and α-TOS while the complex II activity was much more inhibited (IC50=42±8μM α-TOS, 106±8μM α-TNS, respectively) than by α-TOA (IC50 >1000μM). Also the complex III activity was inhibited by α-TNS (IC50=137±6μM) and α-TOS (IC50=315±23μM). Oxygen consumption of NADH- or succinate-respiring SMP, involving the whole electron transfer machinery, was dose-dependently decreased by α-TOS and α-TNS, but only marginal effects were observed in the presence of α-TOA. In contrast to the similar inhibition pattern of α-TOS and α-TNS, only α-TOS triggered O2(-) formation in succinate- and NADH-respiring SMP. Inhibitor studies excluded complex I as O2(-) source and suggested an involvement of complex III in O2(-) production. In cancer cells only α-TOS was reproducibly able to increase O2(-) levels above the background level but neither α-TNS nor α-TOA. Furthermore, the stability of α-TNS in liver homogenates was significantly lower than that of α-TOS. In conclusion, this suggests that α-TNS although it has a structure similar to α-TOS is not acting via the same mechanism and that for α-TOS not only complex II but also complex III interactions are involved.
    Bioorganic & medicinal chemistry 12/2013; · 2.82 Impact Factor
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    ABSTRACT: The present study aims to investigate the protective effects of thymoquinone, the major active ingredient of Nigella sativa seeds, against lead-induced brain damage in Sprague-Dawley rats. In which, 40 rats were divided into four groups (10 rats each). The first group served as control. The second, third and fourth groups received lead acetate, lead acetate and thymoquinone, and thymoquinone only, respectively, for one month. Lead acetate was given in drinking water at a concentration of 0.5g/l (500ppm). Thymoquinone was given daily at a dose of 20mg/kg b.w. in corn oil by gastric tube. Control and thymoquinone-treated rats showed normal brain histology. Treatment of rats with lead acetate was shown to produce degeneration of endothelial lining of brain blood vessels with peri-vascular cuffing of mononuclear cells consistent to lymphocytes, congestion of choroid plexus blood vessels, ischemic brain infarction, chromatolysis and neuronal degeneration, microglial reaction and neuronophagia, degeneration of hippocampal and cerebellar neurons, and axonal demyelination. On the other hand, co-administration of thymoquinone with lead acetate markedly decreased the incidence of lead acetate-induced pathological lesions. Thus the current study shed some light on the beneficial effects of thymoquinone against neurotoxic effects of lead in rats.
    Experimental and toxicologic pathology: official journal of the Gesellschaft fur Toxikologische Pathologie 07/2013; · 1.43 Impact Factor
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    ABSTRACT: Resveratrol interacts with the complex III of the respiratory chain, is a radical scavenger and also suppressor of radical formation in the mitochondria. It reduces the intracellular calcium levels in pre- and postsynaptic neurons and also may inhibit the pro-apoptotic factors in glutamate overflow that occurs, e.g. in excitotoxicity. In cell cultures, glutamate overflow leads to formation of free radicals and results in apoptosis. This increase of radical concentration is enhanced by influx of cations like iron or copper ions into the cell. In present study, the beneficial action of resveratrol was investigated in glutamate-affected dissociated cultures of mice mesencephalic primary cultures. On the 10th day in vitro, 5 mM of glutamate was administered for 15 min and the cultures were further maintained in medium containing 0, 0.01, 0.1 or 1 μM of resveratrol. Resveratrol reduced glutamate-induced damages. The number of dopaminergic neurons was increased and their morphology ameliorated when resveratrol followed glutamate treatment. A significant reduction of glutamate-induced radical formation in cultures treated with resveratrol corresponded with a considerable high antioxidative potential of this stilbene determined using the DPPH assay. In addition, ICP-OES was set up to measure the tissues' copper and iron contents in organotypic cortical cultures of glutamate treated (0 or 30 μM) slices and those in which resveratrol (0, 0.01, 0.1 or 1 μM) was co-administered. Levels of copper were dose-dependently increased, and also the concentration of iron was higher in resveratrol-treated organotypic cultures. The hypothesis that resveratrol has beneficial actions against glutamate damages was verified.
    Journal of Neural Transmission 03/2013; · 3.05 Impact Factor
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    ABSTRACT: Over recent decades, engineered nanoparticles are increasingly produced as the result of the rapid development in nanotechnology. They are currently used in a wide range of industrial and public sectors including healthcare, agriculture, transport, energy, materials, and information and communication technologies. As the result, an increasing concern has been raised over the potential impacts of engineered nanoparticles to human health. In the light of this, it is the purpose of the present review to discuss: (1) novel properties of engineered nanoparticles particularly in biomedical sciences, (2) most recently reported adverse effects of manufactured nanoparticles on human health and (3) different aspects of toxicological risk assessment of these nanoparticles.
    Environmental toxicology and pharmacology. 08/2012;
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    ABSTRACT: Swainsonine (SW) is an indolizidine triol plant alkaloid isolated from the species Astragalus, colloquially termed locoweed. When chronically ingested by livestock and wildlife, symptoms include severe neuronal disturbance. Toxicity to the central and peripheral nervous system is caused by inhibition of lysosomal α-mannosidase (AMA) and accumulation of intracellular oligosaccharide. Consequently, SW has been used as a model substance in investigations of lysosomal storage diseases. Involvement of the basal ganglia has been postulated due to the neuronal symptoms of affected animals. Therefore, primary midbrain cultures from embryonic mice containing dopaminergic neurons were utilized in this study. Neural cells were exposed to SW (0.01-100 μM) for 72 h. AMA activity was 50 % inhibited at 1 μM SW. Cytotoxic changes in cultures were observed above 25 μM SW by increases in lactate dehydrogenase activity and nitric oxide content. Neurotoxicity to dopaminergic cells was visualized by tyrosine hydroxylase immunohistochemistry. Structural degeneration scored as dendritic shortening and shrinkage of cell bodies was dose-dependent and resulted in nerve loss above 25 μM. SW exposure caused progression from reversible to irreversible cytotoxicity. Partial regeneration of AMA-activity in culture was observed on removal of SW. The antioxidative vitamins ascorbic acid and tocopherol (both 100 μM) partially reversed the toxic effect on dopaminergic cells and ascorbic acid decreased AMA inhibition. Thus, neuronal midbrain cell cultures can demonstrate the neurotoxic action of SW and cytoprotective strategies may be tested at a single nerve cell level.
    Journal of Neural Transmission 06/2012; · 3.05 Impact Factor
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    ABSTRACT: Cannabinoids derived from Cannabis sativa demonstrate neuroprotective properties in various cellular and animal models. Mitochondrial impairment and consecutive oxidative stress appear to be major molecular mechanisms of neurodegeneration. Therefore we studied some major cannabinoids, i.e. delta-9-tetrahydrocannabinolic acid (THCA), delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD) in mice mesencephalic cultures for their protective capacities against 1-methyl-4-phenyl pyridinium (MPP(+)) toxicity. MPP(+) is an established model compound in the research of parkinsonism that acts as a complex I inhibitor of the mitochondrial respiratory chain, resulting in excessive radical formation and cell degeneration. MPP(+) (10 μM) was administered for 48 h at the 9th DIV with or without concomitant cannabinoid treatment at concentrations ranging from 0.01 to 10 μM. All cannabinoids exhibited in vitro antioxidative action ranging from 669 ± 11.1 (THC), 16 ± 3.2 (THCA) to 356 ± 29.5 (CBD) μg Trolox (a vitamin E derivative)/mg substance in the 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) assay. Cannabinoids were without effect on the morphology of dopaminergic cells stained by tyrosine hydroxylase (TH) immunoreaction. THC caused a dose-dependent increase of cell count up to 17.3% at 10 μM, whereas CBD only had an effect at highest concentrations (decrease of cell count by 10.1-20% at concentrations of 0.01-10 μM). It influenced the viability of the TH immunoreactive neurons significantly, whereas THCA exerts no influence on dopaminergic cell count. Exposure of cultures to 10 μM of MPP(+) for 48 h significantly decreased the number of TH immunoreactive neurons by 44.7%, and shrunken cell bodies and reduced neurite lengths could be observed. Concomitant treatment of cultures with cannabinoids rescued dopaminergic cells. Compared to MPP(+) treated cultures, THC counteracted toxic effects in a dose-dependent manner. THCA and CBD treatment at a concentration of 10 μM lead to significantly increased cell counts to 123% and 117%, respectively. Even though no significant preservation or recovery of neurite outgrowth to control values could be observed, our data show that cannabinoids THC and THCA protect dopaminergic neurons against MPP(+) induced cell death.
    Phytomedicine: international journal of phytotherapy and phytopharmacology 05/2012; 19(8-9):819-24. · 2.97 Impact Factor
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    ABSTRACT: Hemorrhagic-traumatic shock (HTS) followed by reperfusion induces heme oxygenase (HO) 1. Free iron (Fe2+) may cause oxidative stress, if not adequately sequestered. We aimed to characterize HO-1-mediated effects on Fe2+ levels in liver and transferrin-bound iron (TFBI) in plasma following HTS, including laparotomy, bleeding, and inadequate and adequate reperfusion. Anesthetized rats showed upregulated HO-1 mRNA at 40 min after HTS, which was followed by increased HO activity at 3 h after shock. Fe2+ levels were transiently increased at 40 min after shock, a time point when HO activity was not affected yet. Levels of plasma TFBI were higher in HTS animals, showing the highest levels at 40 min after shock, and decreased thereafter. In addition, we modulated HO activity 6 h before HTS by administering an inhibitor (zinc-protoporphyrin IX) or an activator (hemin) of HO. At 18 h after HTS in all shock groups, HO activity was increased, the highest being in the hemin-pretreated group. The zinc-protoporphyrin IX-treated HTS animals showed increased HO-1 mRNA and Fe2+ levels in the liver compared with the untreated HTS animals. Transferrin-bound iron levels were affected by pharmacological modulation before shock. All animals undergoing HTS displayed increased TFBI levels after reperfusion; however, in animals pretreated with hemin, TFBI levels increased less. Our data indicate that increase in Fe2+ levels in liver and plasma early after HTS is not mediated by HO-1 upregulation, but possibly reflects an increased mobilization from internal iron stores or increased cell damage. Thus, upregulation of HO activity by hemin does not increase Fe2+ levels following HTS and reperfusion.
    Shock (Augusta, Ga.) 08/2011; 36(5):501-9. · 2.87 Impact Factor
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    ABSTRACT: Even though rotenone has been used extensively in recent years to produce a model of Parkinson disease in rats, its systemic effects either on neurons apart from dopaminergic structures or non-neuronal tissues have not been elucidated well. In our present study, 30 adult Sprague-Dawley rats were divided into three even groups. A short-term rotenone-treated group received 10mg/kg b.w. rotenone daily for 7 days. The long-term rotenone-treated group received 3mg/kg b.w. rotenone daily for 30 days. The control group received vehicle only and were kept 5 rats each in parallel to both short- and long-term rotenone treated groups. It was found that short-term rotenone treatment produced marked vascular damages associated with ischemic neuronal degeneration particularly in the thalamus, cerebellum and nucleus dentatus. In long-term rotenone-treated group, vascular changes were less severe and neuronal degeneration was associated with mild microglial proliferation and astrocytosis. Non-neuronal pathology as the result of short-term rotenone exposure consisted of degeneration and necrosis of seminiferous tubular epithelia with formation of spermatide multinucleate giant cells. On the other hand, long-term rotenone treatment did not affect testicles and only caused sinusoidal dilatation in the liver, myocardial degeneration in the heart and interstitial hemorrhages in the kidneys and lungs. In conclusions, damage to blood vasculature by rotenone appeared mediating neuronal and non-neuronal pathology in Sprague-Dawley rats. This effect might provide new insights for ethiopathogenesis of neurodegenerative diseases and contributes to the understanding of hemorrhagic stroke.
    Experimental and toxicologic pathology: official journal of the Gesellschaft fur Toxikologische Pathologie 06/2011; · 1.43 Impact Factor
  • Khaled Radad, Rudolf Moldzio, Wolf-Dieter Rausch
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    ABSTRACT: Ginsenosides are a special group of triterpenoid saponins attributed to medical effects of ginseng. Therefore, they have been research targets over the last three decades to explain ginseng actions and a wealth of literature has been presented reporting on ginsenosides' effects on the human body. Recently, there is increasing evidence on beneficial effects of ginsenosides to the central nervous system (CNS). Using a wide range of in vitro and in vivo models, researchers have attributed these effects to specific pharmacological actions of ginsenosides on cerebral metabolism, oxidative stress and radical formation, neurotransmitter imbalance and membrane stabilizing effects, and even antiapoptotic effects. Modulating these particular mechanisms by ginsenosides has thus been reported to exert either general stimulatory effects on the brain functions or protecting the CNS against various disease conditions. In this review, we try to address the recently reported ginsenosides' actions on different CNS targets particularly those supporting possible therapeutic efficacies in CNS disorders and neurodegenerative diseases.
    CNS Neuroscience & Therapeutics 12/2010; 17(6):761-8. · 4.46 Impact Factor
  • Khaled Radad, Rudolf Moldzio, Wolf-Dieter Rausch
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    ABSTRACT: In Parkinson's disease, most of current therapies only provide symptomatic treatment and so far there is no drug which directly affects the disease process. To investigate the neuroprotective effects of minocycline against long-term rotenone toxicity in primary dopaminergic cell cultures. Embryonic mice of 14-days-old were used for preparation of primary dopaminergic cell cultures. On the 6th day in vitro, prepared cultures were treated both with minocycline alone (1, 5, 10 and 20 microM) and concomitantly with rotenone (5 and 20 nM) and minocycline. Cultures were incubated at 37 degrees C for six consecutive days. On Day in vitro culture medium was aspirated and used for measuring lactate dehydrogenase. Cultured cells were fixed in 4% paraformaldhyde and stained immunohistochemically against tyrosine hydroxylase. Treatment of cultures with 5 and 20 nM of rotenone significantly decreased the survival of tyrosine hydroxylase immunoreactive neurons by 27 and 31% and increased the release of lactate dehydrogenase into the culture medium by 31 and 236%, respectively compared to untreated controls. Minocycline (1, 5, 10 microM) significantly protected tyrosine hydroxylase immunoreactive neurons by 17, 15 and 19% and 13, 22 and 23% against 5 and 20 nM of rotenone, respectively compared to rotenone-treated cultures. Minocycline (only at 10 microM) significantly decreased the release of lactate dehydrogenase by 79% and 133% against 5 and 20 nM of rotenone, respectively. Minocycline has neuroprotective potential against the progressive loss of tyrosine hydroxylase immunoreactive neurons induced by long-term rotenone toxicity in primary dopaminergic cultures.
    The Canadian journal of neurological sciences. Le journal canadien des sciences neurologiques 01/2010; 37(1):81-5. · 1.33 Impact Factor
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    ABSTRACT: Green tea polyphenol epigallocatechin-3-gallate (EGCG) is reported to have antioxidant abilities and to counteract beneficially mitochondrial impairment and oxidative stress. The present study was designed to investigate neuroprotective effects of EGCG on rotenone-treated dissociated mesencephalic cultures and organotypic striatal cultures. Rotenone is a potent inhibitor of complex I of the respiratory chain, which in vitro causes pathological and neurochemical characteristics of diseases in which mitochondrial impairment is involved, e.g., Parkinson's disease. Treatment with EGCG (0.1, 1, 10 muM) alone had no significant effects on mesencephalic cultures. In striatal slice cultures, EGCG led to a significant increase of propidium iodide (PI) uptake and 4-amino-5-methylamino-2',7'-difluorofluorescein diacetate (DAF-FM), but not dihydroethidium (DHE) fluorescence intensity. Rotenone (20 nM on the eighth DIV for 48 h) significantly decreased the numbers and the neurite lengths of TH ir neurons by 23 and 34% in dissociated mesencephalic cell cultures compared to untreated controls. Exposure of striatal slices to rotenone (0.5 mM for 48 h) significantly increased PI uptake, and DAF-FM and DHE fluorescence intensities by 41 and 136 and 19%, respectively, compared to controls. Against rotenone, in dissociated mesencephalic cultures, EGCG produced no significant effect on either the number or neurite lengths of THir neurons compared to rotenone-treated cultures, but EGCG significantly decreased PI uptake by 19% and DAF-FM fluorescence intensity by 19 and 58%, respectively, compared to increase in rotenone-exposed striatal slices. On the other hand, EGCG did not affect superoxide (O(2) (-)) formation as detected with DHE. These data indicate that EGCG slightly protects striatal slices by counteracting nitric oxide (NO(.)) production by rotenone. In conclusion, EGCG partially protects striatal slices but not dissociated cells against rotenone toxicity.
    Journal of Neural Transmission 09/2009; 117(1):5-12. · 3.05 Impact Factor
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    ABSTRACT: Oxidative stress is believed to accompany reperfusion and to mediate dysfunction of the liver after traumatic-hemorrhagic shock (THS). Recently, endoplasmic reticulum (ER) stress has been suggested as an additional factor. This study investigated whether reperfusion after THS leads to increased oxidative and/or ER stress in the liver. In a rat model, including laparotomy, bleeding until decompensation, followed by inadequate or adequate reperfusion phase, three time points were investigated: 40 min, 3 h, and 18 h after shock. The reactive oxygen and nitrogen species and its scavenging capacity (superoxide dismutase 2), the nitrotyrosine formation in proteins, and the lipid peroxidation together with the status of endogenous antioxidants (alpha-tocopherylquinone-alpha-tocopherol ratio) were investigated as markers for oxidative or nitrosylative stress. Mitochondrial function and cytochrome P450 isoform 1A1 activity were analyzed as representatives for hepatocyte function. Activation of the inositol-requiring enzyme 1/X-box binding protein pathway and up-regulation of the 78-kDa glucose-regulated protein were recorded as ER stress markers. Plasma levels of alanine aminotransferase and Bax/Bcl-XL messenger RNA (mRNA) ratio were used as indicators for hepatocyte damage and apoptosis induction. Oxidative or nitrosylative stress markers or representatives of hepatocyte function were unchanged during and short after reperfusion (40 min, 3 h after shock). In contrast, ER stress markers were elevated and paralleled those of hepatocyte damage. Incidence for sustained ER stress and subsequent apoptosis induction were found at 18 h after shock. Thus, THS or reperfusion induces early and persistent ER stress of the liver, independent of oxidative or nitrosylative stress. Although ER stress was not associated with depressed hepatocyte function, it may act as an early trigger of protracted cell death, thereby contributing to delayed organ failure after THS.
    Shock (Augusta, Ga.) 07/2009; 33(3):289-98. · 2.87 Impact Factor
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    ABSTRACT: Epidemiological studies suggest the involvement of pesticides in the etiology of Parkinson's disease. Exposure to rotenone results in degeneration of the nigrostriatal pathway through inhibition of complex I. Organotypic striatal slice cultures were prepared from brains of adult mice and treated with rotenone (0.01, 0.05, 0.1, and 1 mM) for 48 h. Lactate dehydrogenase activity was elevated by 167% at 1 mM of rotenone. Using fluorescent indicators, membrane damage was up to 130% as measured by propidium iodide fluorescence, and superoxide (DHE) and nitric oxide (DAF-FM) formation were increased by 195% and 774% at 1 mM of rotenone, respectively, compared to controls. The study concludes that formation of radicals mediated striatal degeneration by rotenone.
    Annals of the New York Academy of Sciences 01/2009; 1148:530-5. · 4.38 Impact Factor
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    ABSTRACT: Thymoquinone is the main active constituent of Nigella sativa seeds with antioxidant and antiinflammatory properties. In the present study, primary dopaminergic cultures from mouse mesencephala were used to investigate the neuroprotective effects of thymoquinone against MPP(+) and rotenone toxicities. MPP(+) (10 microm on day 10 in vitro (i.v.) for 48 h) significantly decreased the number of THir by 40% compared with untreated control cultures. Rotenone at both short (20 nm on day 10 i.v. for 48 h) and long-term (1 nm on day 6 i.v. for 6 consecutive days) toxicities reduced the number of THir neurons by 33% and 24%, respectively. Treatment of cultures with thymoquinone (0.01, 0.1, 1, 10 microm on day 8 i.v. for 4 days) rescued about 25% of THir neurons at concentrations of 0.1 microm and 1 microm against MPP(+)-induced cell death. Against rotenone, thymoquinone afforded significant protection in both short- and long-term models. In short-term rotenone toxicity, thymoquinone (from days 8-12 i.v.) saved about 65%, 74% and 79% of THir neurons at concentrations of 0.01, 0.1 and 1 microm, respectively, compared with cell loss induced by rotenone. In long-term rotenone toxicity, concomitant treatment of cultures with thymoquinone significantly rescued about 83-100% of THir neurons compared with rotenone-treated cultures. In conclusion, the current study presents for the first time the potential of thymoquinone to protect primary dopaminergic neurons against MPP(+) and rotenone relevant to Parkinson's disease.
    Phytotherapy Research 12/2008; 23(5):696-700. · 2.40 Impact Factor
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    ABSTRACT: Mitochondria are involved in the development of organ failure in critical care diseases. However, the mechanisms underlying mitochondrial dysfunction are not clear yet. Inducible hemoxygenase (HO-1), a member of the heat shock protein family, is upregulated in critical care diseases and considered to confer cytoprotection against oxidative stress. However, one of the products of HO-1 is Fe2+ which multiplies the damaging potential of reactive oxygen species catalyzing Fenton reaction. The aim of this study was to clarify the relevance of free iron metabolism to the oxidative damage of the liver in endotoxic shock and its impact on mitochondrial function. Endotoxic shock in rats was induced by injection of lipopolysaccharide (LPS) at a dose of 8 mg/kg (i.v.). We observed that the pro-inflammatory cytokine TNF-alpha and the liver necrosis marker aspartate aminotransferase were increased in blood, confirming inflammatory response to LPS and damage to liver tissue, respectively. The levels of free iron in the liver were significantly increased at 4 and 8 h after onset of endotoxic shock, which did not coincide with the decrease of transferrin iron levels in the blood, but rather with expression of the inducible form of heme oxygenase (HO-1). The proteins important for sequestering free iron (ferritin) and the export of iron out of the cells (ferroportin) were downregulated facilitating the accumulation of free iron in cells. The temporarily increased concentration of free iron in the liver correlated with the temporary impairment of both mitochondrial function and tissue ATP levels. Addition of exogenous iron ions to mitochondria isolated from control animals resulted in an impairment of mitochondrial respiration similar to that observed in endotoxic shock in vivo. Our data suggest that free iron released by HO-1 causes mitochondrial dysfunction in pathological situations accompanied by endotoxic shock.
    Laboratory Investigation 02/2008; 88(1):70-7. · 3.96 Impact Factor
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    ABSTRACT: Lentiviral vectors have proven to be promising tools for transduction of brain cells in vivo and in vitro. In this study, we have examined the central nervous system (CNS) transduction efficiencies and patterns of a self-inactivating simian immunodeficiency virus (SIVmac)-derived lentiviral vector pseudotyped with glycoproteins from the vesicular stomatitis virus (VSV-G), the amphotropic murine leukemia virus (MLV4070Aenv), the lymphocytic choriomeningitis virus (LCMV-GP), the Ross River virus (RRV-GP) and the rabies virus (RV-G). All glycoproteins were efficiently incorporated into SIV virions, allowing efficient transduction of neuronal cell lines as well as of primary dissociated mouse brain cell cultures. After injection of highly concentrated vector stocks into the striatum of adult mice, quantitative analyses revealed high transduction efficiency with VSV-G pseudotypes, while LCMV-GP and RV-G pseudotypes exhibited moderate transduction efficiencies. MLV4070Aenv and RRV-GP pseudotypes, however, showed only weak levels of transduction after stereotactic injection into the brain. Regarding cell tropism in vivo, VSV-G-pseudotyped SIV vectors transduced neuronal as well as glial cells, whereas all other pseudotypes preferentially transduced neuroglial cells. In addition, we analyzed the influence of the central polypurine tract (cPPT) in context of the VSV-G-pseudotyped SIV transfer vector for infection of brain cells. Deletion of the cPPT sequence from the transfer vector decreased the in vivo transduction efficiency by fourfold, and, more importantly, this modification changed the transduction pattern, since these vectors were no longer able to infect neuronal cells in vivo. Vector injection into the brain did elicit a humoral immune response in the injected hemisphere; however, no gross signs of inflammation could be detected. Analysis of the biodistribution of the vector revealed that, besides the injected brain region, no vector-specific sequences could be detected in any of the organs evaluated. These data indicate SIV vectors as efficient gene delivery vehicles for the treatment of neurodegenerative diseases.
    Gene Therapy 10/2007; 14(18):1330-43. · 4.32 Impact Factor
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    ABSTRACT: Cytokine mRNA expression profiles serve to characterize immune cell activation in different test systems. Both, diluted whole blood and isolated PBMC are widely applied for these studies. Comprehensive data regarding the suitability of different anticoagulants for profiling cytokine expression are not available for the pig. Therefore the aim of this study was to compare the effect of two commonly used anticoagulants (heparin and EDTA) on the cytokine expression pattern of porcine blood cells. IL-1alpha, IL-2, IL-4, IL-6, IL-10 and IFN-gamma mRNA levels were detected ex-vivo and upon in-vitro stimulation in diluted porcine whole blood and isolated PBMC by real-time PCR. The cells were stimulated with ConA or LPS, known to act on different target cells and implying different signalling pathways. Additionally the integrity of the isolated RNA was investigated. Ex-vivo cytokine expression pattern of fresh whole blood were not affected by the investigated anticoagulants. In contrast, stimulation of cultured diluted whole blood or PBMC resulted in significant differences depending on the applied anticoagulant. Using EDTA we found a significantly decreased capacity of whole blood to express cytokines. However, isolated PBMC from EDTA anticoagulated blood showed a higher cytokine expression capacity than PBMC from heparinized blood. Comparing diluted whole blood and PBMC we found that cultured porcine whole blood responded better to bacterial products than isolated PBMC, probably because sufficient auxiliary plasma derived factors such as LPS-binding protein, are present. However, isolated PBMC showed a higher T-cell response than diluted whole blood. In conclusion, our findings underline that each application demands a specific assay system.
    Journal of Immunological Methods 08/2007; 324(1-2):38-47. · 2.23 Impact Factor
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    ABSTRACT: In Parkinson's disease clinical and experimental evidence suggest that neuroinflammatory changes in cytokines caused by microglial activation contribute to neuronal death. Experimentally, neuroinflammation of dopaminergic neurons can be evoked by lipopolysaccharide (LPS) exposure. In mesencephalic primary cultures LPS (100 microg/ml) resulted in 30-50% loss of dendritic processes, changes in the perikarya, cellular atrophy and neuronal cell loss of TH-immunoreactive (TH+) cells. iNOS activity was increased dose dependently as well as prostaglandin E2 concentrations. Ginsenosides, as the active compounds responsible for ginseng action, are reported to have antioxidant and anti-inflammatory effects. Here ginsenoside Rd was used to counteract LPS neurodegeneration. Partial reduction of LPS neurotoxic action was seen in dopaminergic neurons. Cell death by LPS as well as neuroprotective action by ginsenoside Rd was not selective for dopaminergic neurons. Neuronal losses as well as cytoprotective effects were similar when counting NeuN identified neurons. The anti-inflammatory effect of ginsenoside Rd could equally be demonstrated by a reduction of NO-formation and PGE2 synthesis. Thus, protective mechanisms of ginsenoside Rd may involve interference with iNOS and COX-2 expression.
    Journal of neural transmission. Supplementum 02/2007; · 1.07 Impact Factor
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    ABSTRACT: Oxidative stress evoked by excitotoxicity is considered an important factor for the loss of dopaminergic neurons in Parkinson's disease. In vitro, protective effects of the dopamine agonist lisuride on complex I inhibition in primary dopaminergic cell culture have been reported. However, little is known about the effects of lisuride on glutamate-induced radical formation. Here, effects of lisuride on the formation of nitric oxide (NO) and superoxide radicals following glutamate exposure were studied on primary cell cultures prepared from mouse mesencephala. Glutamate treatment resulted in doubling of NO and superoxide radical formation, increased dopaminergic cell degeneration and extensively altered neuronal appearance. Pretreatment with lisuride significantly lowered the levels of either reactive species and increased the survival of dopaminergic neurons compared to glutamate-treated cultures. Moreover, the beneficial effect of lisuride could be completely inhibited by the D2/D3 receptor antagonist sulpiride when co-treated in cultures.
    Journal of Neural Transmission 10/2006; 113(9):1095-105. · 3.05 Impact Factor

Publication Stats

322 Citations
69.01 Total Impact Points

Institutions

  • 2002–2014
    • University of Veterinary Medicine in Vienna
      • Department of Biomedical Sciences
      Wien, Vienna, Austria
  • 2008–2013
    • Assiut University
      • Department of Pathology
      Asyūţ, Muhafazat Asyut, Egypt
  • 2012
    • Northwest A & F University
      • College of Veterinary Medicine
      Yangling, Shaanxi Sheng, China