bluuebunny/crossref_metadata_2025 huggingface dataset:
Assessment of total antioxidant capacity (TAC) of human blood plasma
Authors: Gorąca A. , Lipińska S. , Nowak D.
Published: May 2003

Oxidative stress, initiated by reactive oxygen species is recognized as a pathogenic factor in a variety of organs, e.g. brain, heart, gastric, duodenum, lung. The aim of this study was to estimate plasma TAC of healthy volunteers aged 35–60 years and patients with chronic obstructive pulmonary disease (POCHP). The ferric reducing/antioxidant power (FRAP) assay was used to measure the TAC of human blood plasma. At a low pH a ferric tripyridyltiazine (Fe3+‐TPTZ) complex is reduced to the ferrous (Fe2+) form that causes changes at 593 nm. The antioxidant capacity of the control plasma corresponded to 17.59 ± 1.17 μmol of Trolox activity (a water‐soluble analog of vitamin E). The antioxidant capacity of the plasma obtained from patients with POCHP corresponded to 23.82 ± 1.82 μmol of Trolox activity and was higher (P < 0.02) than from healthy volunteers. This may represent the adaptive response to oxidative stress related to chronic inflammation.

Acknowledgement:  This study was financed by a 502‐11‐809 grant.
Ferritin in Parkinsonian and control brains
Authors: Koziorowski D. , Friedman A. , Gałązka‐Friedman J.
Published: May 2003

Ferritin, the main iron storage protein, may be involved in triggering oxidative stress injury in Parkinson's disease. Aim: To determine the ratio of H and L chains of ferritin and the size of its iron‐core in brain areas with high amounts of iron: substantia nigra (SN), globus pallidus (GP) and hippocampus (Hip). Methods: H/L ratio was determined by ELISA and iron size of ferritin by direct measurements of isolated ferritin with the use of electron microscopy (EM). Material: ELISA was made on 11 control and four Parkinsonian GP, Hip and SN. EM data were obtained from measurements of 50 iron‐cores of ferritin in control GP, SN and Hip. Results: H/L ratios in control brains vs. PD brains were 5.92 ± 1.65 vs. 9.45 ± 1.93 for GP, 5.05 ± 1.67 vs. 11.41 ± 3.47 for SN, 16.01 ± 9.86 vs. 24.85 ± 5.88 for Hip. The sizes of iron‐cores in control brains were 3.3 ± 0.5 nm for GP, 3.7 ± 0.5 nm for SN and 3.1 ± 0.5 nm for Hip. These results may suggest different iron metabolism both in different brain areas and between PD and control.
Isoprostanes, a novel markers of oxidative stress in schizophrenic disorders
Authors: Dietrich‐Muszalska A. , Olas B. , Wachowicz B.
Published: May 2003

Molecular processes including oxidative stress play an important role in pathology of schizophrenia. Isoprostanes are a family of novel prostaglandin isomers and are produced in a free radical catalyzed reactions from arachidonic acid and they are useful as a specific, chemically stable, noninvasive index of free radical generation in vivo. We therefore assessed the level of urinary excretion of 8‐epi‐prostaglandin F2‐marker of lipid peroxidation using an immunoassay kit (Oxis International, Inc.) in urine from schizophrenia and control subjects. According to DSM‐IV criteria all patients had diagnosis of paranoid type. All patients were treated with antipsychotic drugs of II generation (risperidone, quetiapine, olanzapine). Mean time of schizophrenia duration was 4 years. We observed an increased level of isoprostane in urine of schizophrenic patients in comparison with a control group. Our preliminary results support a role of oxidative stress in schizophrenic disorders.
Stan Tuček – a truly European neurochemist
Authors: Bachelard H.
Published: May 2003

Stan Tuček was a neurochemist of international stature whose research encompassed the whole cholinergic field. His collaborations with eminent scientists in Canada, France, the UK and the USA gave him a truly global vision. During the time when contacts between scientists in Eastern Europe and the rest of the world were severely restricted for political reasons, Stan managed to facilitate such contacts, exemplified by the international symposium he organised in 1978 on ‘The Cholinergic Synapse’ in Western Bohemia, where many established cholinergists from the East and West were able to meet for the first time. He was an enthusiastic member of ESN Council, becoming our President in 1984. In 1986 he hosted a most successful meeting of the ESN in Prague at a time of the utmost political difficulty. It was typical of Stan's dedication and ability to work quietly behind the scenes that international political problems were overcome without fuss. As an acknowledged leader in neuroscience he is sorely missed by his many friends throughout the world.
Dysfunction of the ubiquitin–proteasome system in Parkinson's disease
Authors: Jenner P.
Published: May 2003

The cause of nigral cell degeneration and Lewy body formation in Parkinson's disease (PD) remains unknown but may involve impaired proteolysis. Evidence from both sporadic and familial forms of PD suggest the involvement of alterations in the ubiquitin–proteasomal system. In postmortem tissues from PD cases, there is a loss of 26S proteasomal enzyme activity coupled to a decrease in the expression of α‐subunits in substantia nigra while β‐subunit expression remains unchanged. The expression of PA700 is up‐regulated in a number of brain regions in PD but not in substantia nigra. Interestingly, there was little or no expression of PA28 in the nigra in both aged control tissue or in PD. These data suggest that alterations in protein handling may be key to the formation of Lewy bodies in PD. Indeed, in vitro and in vivo inhibition of proteasomal activity causes the death of dopaminergic neurones. Recent evidence suggests that the formation of Lewy bodies may be linked to impaired proteasomal function in centrosomes leading to aggresome formation.
Supraspinal and spinal melanocortin receptors influence morphine nociception
Authors: Starowicz K. , Bilecki W. , Przewłocka B.
Published: May 2003

Melanocortin peptides have been reported to influence opiate tolerance, but the neuronal basis underlying these actions is unknown. We studied the contribution of melanocortin (MC4R) receptors to morphine effects. The MC4R mRNA level in the amygdala was decreased after acute morphine treatment and increased in rats tolerant to morphine as evidenced by quantitative real‐time PCR method. Moreover, the intra‐amygdalar microinjection of antagonist of MC4R attenuated morphine tolerance. Expression of the spinal MC4R after sciatic nerve injury was decreased in the early phase of neuropathy and slightly decreased 2–3 weeks after injury. These findings suggest that the altered melanocortin receptor function may contribute to the development of morphine‐induced effects. Thus, the melanocortin receptors may be a target for development of better and more effective drugs for the therapy of chronic pain.

Acknowledgement:  Supported by KBN grant for the statutory activity.
Mouse and rat VRL‐1 are both expressed in the dorsal root ganglion derived cell line F‐11
Authors: Münter L. , Jahnel R. , Dreger M. , Gillen C. , Hucho F.
Published: May 2003

The TRP‐channel VRL‐1 is a heat‐sensitive, nonselective cation channel expressed by primary sensory neurons and non‐neuronal tissues. VRL‐1 is activated above ∼52°C but not by capsaicin or protons. It has been shown that F‐11 cells, hybridoma of mouse neuroblastoma and rat dorsal root ganglion cells, endogenously express VRL‐1 (1). We here present data on the characterisation of VRL‐1 in F‐11 cells at the nucleic acid and protein level. Anti‐VRL‐1 immunoreactivity showed up at ∼80 kDa in Western blots with F‐11 cell homogenate. By analysing overlapping PCR‐fragments with specific rat VRL‐1 primers we found that F‐11 cells express both rat and mouse VRL‐1. The F‐11 cell line provides a powerful experimental system to study VRL‐1 biochemistry, but one has to be aware that the mouse and the rat protein are expressed.
Expression of the N‐ and C‐termini from the Vanilloid Receptor 1 (VR1) as MBP‐fusion proteins for affinity purification and search for interaction partners
Authors: Jahnel R. , Goswami C. , Si H. , Dreger M. , Gillen C. , Hucho F.
Published: May 2003

The Vanilloid Receptor 1 is a heat‐sensitive, nonselective cation channel expressed by primary sensory neurons involved in nociception. To find and study potential interacting proteins of VR1 we cloned the full N‐ and C‐termini without transmembrane sequences of VR1 into the bacterial expression vector pMALc2x. We here report the expression and purification of the VR1 fragments fused to the maltose binding protein (MBP). In addition, we assessed the subcellular targeting of N‐ and C‐terminal VR1 fragments expressed in the cell line F‐11. This cell line has recently been shown to be particularly suited for the expression of VR1 (1). Preliminary data suggest that the VR1 N‐terminal fragment is targeted to membranes despite the lack of predicted transmembrane regions.
Peripheral effects of opioids and nociceptin in neuropathic pain
Authors: Obara I. , Starowicz K. , Bilecki W. , Przewłocki R. , Przewłocka B.
Published: May 2003

Recent studies have pointed to the role of peripheral receptors in chronic pain process. They are located on nerve fibers, which project to dorsal root ganglion (DRG). We demonstrated using RT PCR method that peripheral nerve injury caused a reduction in a number of mu‐opioid receptors in DRG. We also checked the peripheral effects of opioid (morphine, DAMGO, EM‐1, EM‐2) and ORL‐1 (nociceptin) receptor agonists. Our findings show that intraplantarly administered agonists were effective in antagonizing allodynia. Peripheral mu‐opioid and ORL1 receptors mediate the observed effects as was evidenced by treatment with naloxone methiodide, which is only peripherally active. The present results demonstrated that opioids after peripheral treatment, in spite of decreased expression of mu‐opioid receptor mRNA in DRG, are effective and their peripheral use may eliminate central unwanted side‐effects.

Acknowledgement:   Supported by EU grant (No. QLRT‐2001‐02919).
Differential activation of C1 complement components in rat spinal cord after sciatic nerve injury
Authors: Mika J. , Przewłocka B. , Stover C. , Schwaeble W. J. , Weihe E. , Schäfer M. K.‐H.
Published: May 2003

Neuroimmune interactions are discussed to drive neuropathic pain. We used the Bennett model to correlate pain and cellular expression profiles of the complement factors C1q and C1q‐associated serine proteases C1r/C1s in lumbar spinal cord. At 2 days C1q mRNA levels increased ipsilateral to the lesion, and peaked at 8 days when allodynia and severe walking problems were present. During regeneration walking problems disappeared together with C1q mRNA levels. C1q biosynthesis was restricted to microglia. Surprisingly, C1s/C1r biosynthesis was not increased after injury suggesting a role for C1q different from classical complement activation. Sustained C1q expression in spinal microglia after lesion in conjunction with pain behavior indicates that microglial C1q may be causally involved in the development and maintenance of neuropathic pain.

Acknowledgements:  Supported by BMBF01GG9818, SFB297, DFGWE910/8‐3, KBN3P05C00623.
Characterization of nociceptin binding sites by novel peptide analogs and radioprobes
Authors: Benyhe S. , Gündüz Ö. , Farkas J. , Kocsis L. , Sipos F. , Ligeti M. , Magyar A. , Orosz G. , Tóth G. , Borsodi A.
Published: May 2003

A number of new synthetic nociceptin ligands were studied in receptor binding and functional tests in rat brain membranes and in cloned systems. Ligand binding experiments were performed with three different radioprobes developed in our lab. The nociceptin derivatives exhibited high affinity in competition experiments. Receptor‐mediated G‐protein activation was determined in [35S]GTPgS binding assays. Among the new structures examined, Ac‐RYYRIK‐ol was found to be only a weak stimulator by itself, whereas this compound inhibited receptor‐mediated G‐protein activation. These data suggest that Ac‐RYYRIK‐ol is a high affinity peptide antagonist for the nociceptin receptor.

Acknowledgements:  Supported by the Hungarian Scientific Research Fund OTKA T‐035211, T‐033078, T‐030841, and the Ministry of Education, NKFP 1/027 Hungary.
Regulation of cellular function through stem cell factor and c‐Kit receptor in the cerebellar cell culture
Authors: Won Y. J. , Suh J. Y. , Cho S. W. , Kim D. , Hong H. N.
Published: May 2003

Evidence that stem cell factor (SCF) and c‐Kit receptor tyrosine kinase expressed in the cerebellum during postnatal development, suggests a possible contribution of the SCF/Kit signaling pathway in the cerebellar development. In the present study, we prepared cerebellar cultures from C57Bl/6J mouse at postnatal day 6 to investigate the role of c‐Kit receptor and SCF in regulation of cell growth and viability in the postnatal cerebellar cells. SCF increased the number of survival cells and density of calbindin and GFAP expression in the immunoblot analysis. Treatment with c‐Kit antibody accelerated cellular loss in serum‐free media and decreased the expression of calbindin and GFAP. The recovery effects of SCF on the cellular proliferation and the expression of functional proteins in the cultures containing c‐Kit antibody suggest an involvement of SCF/Kit pathways in the control of postnatal development of cerebellar cells.
Neural stem cell line derived from human umbilical cord blood – morphological and functional properties
Authors: Bużańska L. , Stachowiak E. , Stachowiak M. , Domańska‐Janik K.
Published: May 2003

Human umbilical cord blood (HUCB) were shown to be a source of stem cells which can be differentiated into neural cell types and can integrate into the rat brain upon the transplantation. We succeeded in isolating and establishing a neural stem/progenitor cell line from HUCB. Early and late passages were compared for growth kinetics and the ability to differentiate into neurons, astrocytes and oligodendrocytes. After 2 years in culture HUCB‐derived NS/PCL display normal chromosomal pattern and, as shown by BrdU incorporation and increase in cell number, remain unchanged ability to proliferate and self‐renew. The presence of EGF and FGF receptors were confirmed. Upon differentiation induced by dBcAMP/ascorbic acid, in both early and late passages, neuron‐specific proteins (internexin, GluR2, GAD 65, GAD 67 and TH) were expressed and, as shown by HPLS, monoamines (5‐HT and dopamine metabolites) were produced.
Changing electrophysiological properties in differentiating human cord blood‐derived neural stem cells
Authors: Bużańska L. , Sun W. , Salvi R. J. , Domańska‐Janik K. , Stachowiak M. K.
Published: May 2003

Ion channels were assessed on both differentiated and nondifferentiated human cord blood‐derived neural stem cells (HUCB‐NSC). HUCB‐NSC displayed two types of voltage‐sensitive currents: (1) hyperpolarization‐activated inward current [Ih] and (2) outward rectifying K+ current [IK+]. Ih was recorded from most of the neuron‐shaped HUCB‐NSC differentiated with dBcAMP/ascorbic acid for 12 days. Ih was blocked by external Cs+ (5 mm) and recovered after Cs+ removal. Ik+ was recorded from approximately 40% of cAMP/ascorbic acid‐differentiated cells and was blocked by TEA (15 mm) or 4‐AP (1 mm), but not by externally applied Cs+. While nondifferentiated HUCB‐NSC also displayed Ih, none displayed IK+. Differentiated HUCB‐NSC expressed ligand‐gated channels indicated by (1) kainic acid (KA), a non‐NMDA glutamate‐receptor agonist‐ and (2) serotonin‐evoked inward currents. KA‐induced current was not observed in nondifferentiated HUCB‐NSC.
The influence of Id1 protein on human stem cells differentiation into neuronal pathway
Authors: Jurga M. , Bużańska L.
Published: May 2003

Id1 protein is responsible for inhibition of bHLH transcription factors. It lacks basic region necessary for DNA binding and after dimerization with other bHLH proteins, competitively blocks their function. Relatively high expression of Id1 in cancer cells suggests its role in promoting cell division. To study the influence of Id1 protein on human neural stem/progenitor cells differentiation Dev and HUCB‐NS/P (human umbilical cord blood derived neural stem/progenitor) cell lines were applied. Id1 gene in sense and antisense orientation was introduced into cells with pEGFP‐N1 vector by electroporation. Overexpression of Id1 results in de‐differentiation of the cells in both experimental models. In contrast, transfection with antisense Id1 results in promotion of neuronal differentiation but only in HUCB‐NS/P cells. These results show the influence of Id1 on neural stem cells differentiation and its unique selectivity referred to neurogenesis inhibition.

Acknowledgements:  Funded by Polish State Committee for Scientific Research (grant no. 76P05A.04920).
Lipid analyses of human brain rafts
Authors: Molander‐Melin M. , Blennow K. , Bogdanovic N. , Dellheden B. , Mansson J. E. , Fredman P.
Published: May 2003

Few studies of lipid rafts have investigated gangliosides in brain tissue. This study focus on analyses of lipids and the major brain gangliosides (GM1, GD1a, GD1b, GT1b) in human cortex (frontal, temporal) and corresponding detergent resistant membranes (DRMs), i.e. rafts. A high proportion of the gangliosides (18–26%) as well as of cholesterol (21%) and sphingomyelin (38%) was found in rafts, while lower yields was observed for ganglioside GM2 (9%), phospholipids (8%) and in particular proteins (2%). Significant alterations in lipid composition was noticed in rafts from Alzheimer brain tissue. These results show that sphingolipids and cholesterol are major constituents of rafts also in the human brain and that the main brain gangliosides are distributed in rafts to a similar degree. Moreover, lipid rafts might be considered in the pathology of Alzheimer's disease.
Estrogen‐mediated protection against methamphetamine‐induced inflammatory pathways in human brain endothelial cells
Authors: Lee Y. W. , Małecki A. , Toborek M.
Published: May 2003

Recent evidence has demonstrated the potential role of estrogens as therapeutic agents in the prevention or treatment of neurodegenerative diseases, such as Alzheimer's disease, Parkinson's disease or stroke. The present study focused on the protective mechanisms of estrogens in the methamphetamine (METH)‐mediated inflammatory reactions in human brain microvascular endothelial cells (HBMEC). Pretreatment with estrogens markedly blocked the activation of redox‐responsive transcription factors, such as AP‐1, NF‐kappaB and CREB, in HBMEC exposed to METH. In addition, estrogens inhibited METH‐induced expression of inflammatory genes in HBMEC. These results suggest that estrogens may attenuate the METH‐induced inflammatory cerebrovascular environments via blocking the transcription factor‐mediated molecular signaling pathways in human brain endothelial cells.

Acknowledgements:  Supported by NIH; NS39254, MH63022, and AA013843.
The correlation between Hsp70 and morphological findings in brain of Morris hepatoma bearing rats
Authors: Michalak S. , Adamczewska‐Goncerzewicz Z. , Szczech J.
Published: May 2003

The remote effect of cancer presents clinically paraneoplastic syndromes. Hsp are chaperons involved in response of CNS to pathological conditions. We analysed Hsp 70 expression in CNS (Western blotting) in course of neoplastic disease. Buffalo rats bearing Morris hepatoma were sacrificed at 21st day after inoculation. We found increased expression of Hsp 70 in white matter (107 ± 5%, mean ± SD, in relation to control), cerebellum (124 ± 16%), and brain stem (121 ± 19%). The microscopical examination revealed venostasis in hemispheres, oedema in the region of corpus callosum and shrinkage of the neurons in dentate gyrus, cingulate gyrus, temporal and parietal lobe. In cerebellum of tumor bearing rats we noticed segmental atrophy of Purkinje cells. The morphological findings consistent with neuropathological features of paraneoplastc syndromes are associated with increased expression of Hsp 70 in course of experimental neoplastic disease in rat.
Palmitoylcarnitine interferes with interaction between protein kinase C (PKC)βII and its receptor – RACK
Authors: Sobiesiak‐Mirska J. , Nałęcz K. A.
Published: May 2003

Palmitoylcarnitine (Pcar), reported to promote differentiation of neuroblastoma NB‐2a cells, was observed to inhibit activity of PKC by decreasing the ability of binding its activators (phorbol esters) and autophorylation on serine moiety (Neurochem. Int. 2003, 42, 45). Two PKC isoforms, β and δ were retarded in the cytoplasm upon exposure to Pcar (Biochim. Biophys. Res Commun. 2002, 294, 823). An interaction between PKCβII and its receptor was further studied and it was demonstrated that RACK forms much more stable complex with PKCβII in the absence of ATP, an interaction which was shown to be decreased by Pcar. Pcar also diminished colocalisation of βII and RACK at the plasma membrane. In the presence of ATP, under conditions not affecting phosphorylation on threonine, the amount of RACK in a complex with PKCβII was not changed by Pcar, indicating that the first two phosphorylations are sufficient for the complex formation.
NO participate in the communication between the first‐ and second‐order neurons in the trigeminal sensory tract in the dog
Authors: Maršala J. , Lukáčová N. , Pavel J. , Silvášiová M. , Kuchárová K. , Maršala M.
Published: May 2003

Histochemical, immunocytochemical and radioassay study was performed to detect the occurrence of NOS‐immunoreactive primary trigeminal sensory somata in the trigeminal ganglion, including their fiber components. Spinal trigeminal tract and sensory trigeminal nuclei were studied using the same methods. It was found that more than 30% of all somata in the trigeminal ganglion are NOS immunoreactive. Corresponding fibers were detected in the spinal trigeminal tract. NOS immunoreactive fibers of three different categories could be followed to terminate in the sensory trigeminal nuclei. Data presented here confirm that trigeminal sensory system is richly endowed with NOS and that NO is used to communicate between the first and second‐order trigeminal sensory neurons.

Acknowledgements:   Supported by VEGA Grant no. 2/3217/23PS9, STAA Grant no. 51‐013002 and by NIH grants NS 32794 and NS 40386 to M.M.
The effect of cauda equina constriction on nitric oxide synthase activity
Authors: Lukáčová N. , Kafka J. , Cižková D. , Maršala M. , Maršala J.
Published: May 2003

The effect of cauda equina constriction (CEC) on nitric oxide synthase (NOS) activity has been studied in spinal cord of the dog. CEC lasting for 2 days caused significant increase in NOS activity in white matter of lumbar segments. The enzyme activity decreased to basal levels 5 days after injury. An extreme reduction of NO formation has been seen in sacral segments at 2 day of postsurgery. At 5 day, the enzyme activity greatly increased and in gray matter significantly exceeded baseline. Quantitative measurement of NOS activity produced a rise in gray matter of thoracic segments and indicated a decrease in gray matter of upper lumbar segments. The results indicate a time‐dependent formation of nitric oxide after CEC in spinal cord segments and regions.

Acknowledgements:  Supported by VEGA Grants no. 2/2079/22 and 2/3217/23PS9, STAA Grant no. 51‐013002 and by NIH grants NS 32794 and NS 40386 to M.M.
Endocannabinoids, their effect on GABA uptake in globus pallidus and relevance to Parkinson's disease
Authors: Venderova K. , Brotchie J. , Brown T. , Ruzicka E. , Visnovsky P.
Published: May 2003

Within the globus pallidus, CB1 cannabinoid receptors are localized presynaptically on GABAergic neurons. We focused on effect of endocannabinoids on GABA uptake in rat globus pallidus slices. Following incubation with 2‐arachidonyl glycerol (2‐AG) (1 and 3 μm), there was a 40%, and 30% increase, respectively, in [3H]‐GABA uptake (P < 0.05). When incubated with noladin ether (1 μm), an increase of 57% was observed (P < 0001). The effects of 2‐AG were reversed by the CB1 receptor antagonist AM 251 (1 μm), showing this mechanism is likely to be CB1 receptor‐mediated (P < 0.05). Neither anandamide (0.1–10 μm) nor synthetic cannabinoid WIN 55,212–2 (1–100 μm) had any effect. We suggest increased level of endocannabinoids, found in a Parkinson's disease model, might thus represent a compensatory mechanism.

Acknowledgement:  Supported by CEZ:J13/98:11600004.
Effect of sphingosine‐1‐phosphate on calcium signaling in cerebellar astrocytes and neurons
Authors: Viani P. , Ferraretto A. , Gravaghi C. , Giussani P. , Bassi R. , Tettamanti G. , Riboni L.
Published: May 2003

Sphingosine‐1‐phosphate (SP1P) is a sphingoid molecule implicated in the control of many biological processes in different cells including those of the nervous system. Also in brain cells SP1P can function as an extracellular signal, through binding to specific receptors, or as second messenger of stimuli able to activate sphingosine kinase. SP1P has been reported to directly act on internal Ca2+ stores or induce a Ca2+ signal through the coupling of its receptors with PLC. We investigated the effect of SP1P on Ca2+ signaling in cells of the nervous system and found that administration of SP1P induced an increase of [Ca2+]i in astrocytes but not in differentiated granule cells. SP1P stimulated the production of inositol phosphates and increased [Ca2+]i by mobilization from intracellular stores, thus acting as an extracellular mediator in astrocytes. Our data suggest SP1P may act as activator of calcium‐mediated events and play a role in glial function and dysfunction.
Cerebrocortical plasma membrane serine base exchange enzyme activity in hypoxia
Authors: Buratta S. , Andreoli V. , Felicetti M. , Mozzi R.
Published: May 2003

Phosphatidylserine (PtdSer) is involved in signal transduction and in apoptosis. Peculiarities of its metabolism (1) are relevant for this study. N2 treatment stimulates the incorporation of [14C]serine (Ser) into PtdSer of cerebrocortical slices and in cerebrocortical plasma membranes (PM) serine base exchange enzyme (SBEE) activity is lowered by G protein activator. PtdSer radioactivity of PM from slices incubated with [14C]Ser was greater in hypoxia than in controls. SBEE activity of PM from slices, incubated in a similar manner and assayed at pH 8.2 and pH 7.4 based on a preliminary study, was lower in hypoxia. The hypoxia induced incorporation of [14C]Ser into slice PtdSer was due to stimulation of the SBEE isoform that exchanges Ser and ethanolamine and that in brain membrane is activated by fatty acids. We suggest the presence of different SBEE isoforms in PM differently influenced by hypoxia.
Sulfatide is expressed in neurons and astrocytes and accumulates at degradation deficiency
Authors: Pernber Z. , Molander‐Melin M. , Mansson J. E. , Gieselmann V. , Fredman P.
Published: May 2003

Sulfatide expression was explored in adult rat gray matter, using the Sulf I antibody and immunohistochemistry. To further explore sulfatide metabolism an arylsulfatase enzyme deficient mice model were used, resembling metachromatic leukodystrophy (MLD) characterized by lysosomal sulfatide storage. Analyses showed sulfatide staining in subpopulations of neurons and astrocytes, and in particular the neurons showed more staining in the ASA‐deficient mice, indicating a higher turnover of sulfatide. These results demonstrate sulfatide expression beyond myelin and oligodendrocyte progenitors, and the intracellular localized sulfatide in neurons and astrocytes indicate other roles than in myelin. The accumulation of sulfatide in neurons might be part of the pathological process in MLD and explain known symptoms unlikely to be related to the well‐established white matter disturbances.
On‐line glucose and lactate monitoring in rat striatum: effect of malonate and correlation with histological damage
Authors: Skjoeth‐Rasmussen J. , Lambertsen K. , Gramsbergen J. B.
Published: May 2003

Microdialysis of glucose, lactate and glycerol was performed to monitor brain insults and to predict brain injury in a rat model using the mitochondrial toxin malonate (5–100 mm). Striatal dialysates were analyzed off‐line using a CMA 600 microdialysis analyzer or on‐line using flow‐injection analysis and biosensors for glucose and lactate. Histological damage was evaluated using stereological principles. Lactate (baseline ca. 1 mm) was dose‐dependently increased, reaching a maximum of five‐ to six‐fold increase, whereas glucose (baseline 1–2 mm) was decreased (>50%) by malonate >20 mm. These changes were reversible upon perfusion with normal Ringer's. Transient increases in glycerol (four‐ to eight‐fold) were only observed in some rats, and were not dose‐dependent. Histological damage was related to the perfused malonate concentration, but was not significantly correlated with lactate or glycerol changes.
Transient forebrain ischemia modulates focal adhesion kinase (FAK)‐mediated signal transduction in gerbil hippocampus
Authors: Ziemka‐Nałęcz M. , Sarnowska A. , Zalewska T.
Published: May 2003

Focal adhesion kinase (FAK) is thought to play a major role in conveying survival signals from extracellular matrix (ECM). Phosphorylated FAK may interact with other nonreceptor kinases such as Src, and adaptor molecule Cas, perhaps providing a pathway by which ECM may regulate cell viability. In the present study the expression and tyrosine phosphorylation of FAK, Src and Cas after 5 min of global ischemia were investigated. The primary activation/phosphorylation of FAK, observed during first 6 h after ischemic injury, was followed by its profound down‐regulation. At 72 h of reperfusion the level of phosphorylated FAK decrease to about 50% of the control. The decrease of FAK phosphorylation coincides with its proteolytic degradation. Cleavage of FAK coincided temporally with the loss of Src and Cas. Ischemia‐induced proteolytic processing of the investigated proteins may lead to the interruption of ECM‐derived signals and compromise neuronal survival.

Acknowledgements:  Sponsored by SCSR 4P05A 08619 and Med. Res. Ctr.
Transglutaminase increases during astrocyte differentiation by interplay of growth factors and steroids
Authors: Ientile R. , Campisi A. , Raciti G. , Caccamo D. , Curro’ M. , Cannavo’ G. , Macaione S. , Vanella A. , Avola R.
Published: May 2003

Development of primary cultured astrocytes can be influenced by interplay of steroids and growth factors (GFs). These mytogenic polypetides regulated the expression of cytoskeletal proteins depending on pretreatment with either dexamethasone (DEX) or estradiol (E2). We evaluated the contribution of each of these treatments to the expression of tissue transglutaminase (tTG), that is involved in cell differentiation. Treatment for 12 h with E2 and EGF as well as DEX and IGF‐I significantly increased tTG expression in 15 DIV astrocyte cultures. A proliferative marker, such as cyclinD1 decreased as consequence of treatment increasing tTG expression. Taken together, these results indicate that steroid‐GFs cross‐talk plays a crucial role during astroglial cell maturation, and tTG may be indicated as mediator of the proliferative/differentiative response of primary cultured astrocytes.
HO‐1 expression in primary cultured astroglial cells
Authors: Li Volti G. , Ientile R. , Vanella A. , Cannavo’ G. , Raciti G. , Curro’ M. , Campisi A.
Published: May 2003

Heme oxygenase (HO)‐1 catalyzes the rate‐limiting step in heme degradation. The aim of the study was to determine HO‐1 expression and distribution pattern in glial cells during differentiation and after exposure to glutamate (GLU) (100 μm). In untreated cells at 7 days in vitro (DIV) HO‐1 expression was undetectable whereas increased at 14 and 21 DIV. Exposure to GLU for 24 h at 7, 14 and 21 DIV increased the expression of HO‐1; this effect was prevented by preincubation with GYKI 52466. In untreated cells at 7 DIV, HO‐1 fluorescence was weak; the protein appeared in the cytosol and the fluorescence intensity increased at 14 and 21 DIV. Compared with untreated cells, the addition of GLU increased the fluorescence and the enzyme translocated in the nucleus and nucleoli. These results demonstrate the presence of HO‐1 in the glial cells and the translocation in the nuclear compartment of astrocytes during differentiation.
Interaction of potassium channel openers with glioma cells mitochondria
Authors: Dębska G. , Kicińska A. , Skalska J. , Szewczyk A.
Published: May 2003

Benzimidazolones such as NS1619 and NS004 have been reported to activate plasma membrane large conductance Ca2+ activated potassium channel (BK‐type K(Ca)). In the present study we have examined the effect of NS1619 and NS004 plasma membrane BK‐ channel openers on mitochondria in glioma cells. We described the effect of BK‐channel openers on mitochondrial membrane potential (ΔΨm), on mitochondrial respiration and membrane bilayer conductance. We have shown that BK channel openers caused significant decrease in ΔΨm with an EC50 value of 3.6 ± 0.4 μm for NS1619 and 5.4 ± 0.8 μm for NS004. This membrane depolarization was produced by inhibition of mitochondrial respiratory chain, probably complex I. Both BK‐channel openers had no effect on membrane bilayer current or conductance.

Acknowledgement:  This work was supported by State Committee for Scientific Research grant 6P04A01219.
Abstracts: 1
Authors: Strużyńska L. , Dąbrowska‐Bouta B. , Sulkowski G. , Rafałowska U.
Published: May 2003

Lead (Pb) is a known neurotoxic agent, however, mechanisms of its neurotoxicity are still an open question. The aim of the study was to assess the function of nerve endings and astroglia in regard to the relationships between GABA, glutamate and glutamine using the rodent model of Pb toxicity. Synaptosomal processes of radioactive neurotransmitter transport, both GABA and glutamate, were impaired. Moreover, the uptake of glutamine, involved in the neuronal recycling of the neurotransmitters GABA and glutamate, decreased. However, evidences of astroglial activation (enhanced uptake of glutamate and activation of glutamine synthetase) were observed, together with parallel existing weakness of glutamine transport. The results suggest that the disturbances in GABAergic and glutamateric neurotransmission may be partially the effect of impaired neuronal–astrocytic interaction, mainly in intercellular trafficking of glutamine.
Neuroprotection of zinc against apoptotic cell death in model of anoxia in vitro
Authors: Nagańska E. , Matyja E. , Zielińska M. , Gębarowska J.
Published: May 2003

Zinc is the trace element considered the one of the etiological agents involved in nerve cell damage in certain human neurodegenerative disorders. Growing evidence indicates the diverse effect of zinc ions, associated with its neuroprotective and neurotoxic abilities. We examined the effect of zinc on the evolution of anoxia‐induced neuronal injury in the organotypic cultures of rat hippocampus. The cultures had been pretreated with ZnCl2 (25–500 μm) 30 min prior anoxia. The ultrastructural findings documented dose‐dependent ability of Zn to reduce anoxia‐induced neuronal changes in hippocampal neurones in vitro. The significant neuroprotection involved the development of late apoptotic changes, whereas the early necrotic anoxia‐induced neuronal injury was not significantly reduced. However, the quite‐well preserved pyramidal neurones displayed the mitochondrial abnormalities, reflecting the combined neuroprotective and neurotoxic Zn properties.
Zinc ionophores as neuroprotective agents
Authors: Gulyaeva N. , Stepanichev M. , Onufriev M. , Lazareva N. , Fliss H.
Published: May 2003

Zinc ionophores, molecules that carry zinc ions across the cell membrane, can decrease apoptosis in animals subjected to experimental heart attack, brain injury, neurodegeneration, and epilepsy. Here we show that zinc ionophores at low μg/kg BW doses have neuroprotective effects in three different stroke models in rodents: focal ischemia models (middle cerebral artery occlusion, MCAO) in mice and rats, and a model of global ischemia (four vessel occlusion, 4VO) in rats. Intravenous, postinjury, administration of zinc ionophores decreased neuronal cell death, the number of TUNEL‐positive cells in the lesioned brain areas, and brain infarct volumes. Zinc ionophores also significantly accelerated functional recovery after MCAO.
Alteration of zinc accumulation in ageing and neurodegenerative disorders
Authors: Szczerbowska‐Boruchowska M. , Lankosz M. , Adamek D. , Ostachowicz J. , Tomik B. , Krygowska‐Wajs A. , Szczudlik A. , Bohic S. , Simionovici A. , Chwiej J.
Published: May 2003

The X‐ray fluorescence techniques were applied for study of Zn accumulation in CNS tissue. Concentration of this element was determined in white and gray matter of the brains without any neurodegeneration processes with respect to ageing. Significant increase of Zn accumulation with age was observed in white matter. As is supposed, Zn may also play an important role in neurodegeneration. Topographic and quantitative analysis of this element was performed for Parkinson's disease (PD) and amyotrophic lateral sclerosis (ALS). The study was performed in tissue slices taken from substantia nigra (SN) and spinal cord. The results showed that accumulation of Zn in PD neurones of SN is significantly increased in comparison with the control, meanwhile degenerated motor neurones of spinal cord in ALS reveal decreased level of Zn.
Energy on demand: a mechanism for astrocyte–neuron metabolic coupling
Authors: Magistretti P. J. , Pellerin L. , Chatton J.‐Y. , Pierre K.
Published: May 2003

A tight link exists between neuronal activity and energy metabolism. This relationship was first proposed by Roy and Sherrington who suggested that brain possesses intrinsic mechanisms to regulate the availability of energy substrates in register with local variations of functional activity. This concept was later confirmed by Sokoloff and colleagues who demonstrated that increased neuronal activity led to increased glucose utilization in almost any areas of the brain tested. Despite wide acceptance of this concept, the cellular and molecular mechanisms that underlie this close relationship between neuronal activity and energy metabolism have remained largely unknown. The extensive analysis carried out by our group will be discussed. Astrocytes appear to be the key cells that operate the coupling between synaptic activity and glucose utilization. Indeed both in vitro and in vivo evidences indicate that astrocytes can detect synaptically released glutamate through sodium‐coupled uptake operated by glutamate transporters. Disruption of sodium homeostasis activates the energy‐demanding Na‐K‐ATPase which promotes glucose uptake and lactate production. Relevance of these findings to functional brain imaging will be discussed.
Glial–endothelial communication in physiology and pathology
Authors: Abbot N. J.
Published: May 2003

The blood–brain barrier (BBB) is formed by the endothelial cells of cerebral microvessels; it protects the brain from circulating neuroactive agents, and contributes to CNS homeostasis. The BBB phenotype develops under the influence of associated brain cells, especially astrocytic glia; it consists of complex tight junctions (physical barrier), and specific transport and enzyme systems which regulate molecular traffic. Candidate molecules for inductive signals include TGFb, GDNF, bFGF, IL‐6 and steroids. Endothelial factors (LIF) may induce glial differentiation; thus endothelium and astrocytes are involved in two‐way inductive communication. In addition, astrocytes and other cells can release chemical factors that modulate endothelial permeability over a time‐scale of seconds to minutes. This talk will focus on the mechanisms involved in glial:endothelial communication, the role in normal physiology, and disturbances of glial:endothelial communication in pathology. Abbott N. J. (2002) J. Anat. 200, 629–638.
Volume transmission in health and disease: communication via the brain extracellular space
Authors: Syková E.
Published: May 2003

An important means of communication between neurons and neurons and glia is extrasynaptic ‘volume’ transmission, which is mediated by diffusion in the extracellular space (ECS). Following their release, a number of neuroactive substances, including ions, mediators, metabolites and neurotransmitters, diffuse via the ECS to targets distant from their release sites. Glial cells and the extracellular matrix affect the composition, geometry and volume of the ECS and therefore also extracellular diffusion during development, aging and pathological states such as ischaemia, injury, X‐irradiation, gliosis, demyelination and in grafted tissue. Changes in diffusion parameters affect neuron–glia communication, ionic homeostasis and the movement and accumulation of neuroactive substances and therefore play an important role in volume transmission in functions such as vigilance, sleep, depression, chronic pain, LTP, memory formation and other plastic changes in the CNS.
Transporter mediated regulation of neural communication
Authors: Caron M. G.
Published: May 2003

Neurotransmitter transporters play a fundamental role in the regulation of neuronal activity by removing released transmitters from the extraneuronal space. To evaluate the precise role of the dopamine transporter (DAT) we have inactivated the DAT gene in mice. Deletion of the DAT gene (DATKO) leads to a pronounced hyperdopaminergic state and remarkable neurochemical and biochemical changes. These neurochemical changes are hallmarks of neuronal systems in the absence of functional reuptake. In the DATKO mice the elevated dopamine can induce neurodegeneration of nondopaminergic neurons in the striatum. DATKO mice develop severe motor symptoms of dyskinesia and ataxia, associated with a selective loss of striatal dopamine responsive GABAergic medium spiny neurons, and the concomitant appearance of biochemical markers of neurodegeneration and apoptosis. These findings uncover a previously unappreciated relationship between elevated extracellular dopamine, sustained intracellular dopaminergic signaling and striatal neuronal degeneration.
Interaction between mitochondria and oxidative stress in neuronal injury
Authors: Reynolds I. J. , Filiano A. J. , Malaiyandi L. M. , Rintoul G. L. , Votyakova T. V.
Published: May 2003

Mitochondria may be both the source and the target of oxidative stress in neurodegenerative disease. In models of excitotoxicity, neuronal injury is triggered by the influx of calcium into neurons and then into mitochondria. Our studies suggest that an important consequence of this calcium movement is the generation of ROS by mitochondria. Studies with isolated mitochondria suggest that calcium may enhance ROS generation by mitochondria, especially when complex I is impaired. However, these studies are complicated by a lack of specificity of detection methods like Amplex Red. One feature of mitochondria is their movement within neurons. We used fluorescent proteins targeted to mitochondria to follow trafficking in neurons. Neurotoxins like glutamate, zinc and peroxide, which feature oxidative stress in their mechanism of action, affect mitochondrial movement, morphology or both. We speculate that restricting the delivery of mitochondria to their targets within neurons could impair neuronal viability.
Oxidative stress and neuronal mitochondrial function. Factors dictating susceptibility
Authors: Heales S. J. R.
Published: May 2003

Oxidative stress and loss of neuronal mitochondrial function, particularly at the level of cytochrome oxidase has been implicated in the neurodegenerative process. Cell culture studies have revealed that neurones, in comparison to astrocytes, may be particularly susceptible, when cultured alone, to the action of oxidising species such as nitric oxide and peroxynitrite. An important factor in dictating such susceptibility appears to be the intracellular level of the antioxidant, glutathione (GSH). Whilst the coculture of neurones with nitric oxide generating astrocytes leads to neuronal mitochondrial damage, such damage appears to be initially limited due to the up‐regulation of neuronal GSH status by astrocytes. Other factors that may dictate the susceptibility of brain cell types to oxidative stress include the ability of cells to up‐regulate glycolysis in the face of mitochondrial damage and cellular ubiquinone availability.
Mitochondria: inducers and targets of oxidative stress
Authors: Adam‐Vizi V.
Published: May 2003

The mitochondrial electron transport chain is an important source of reactive oxygen species (ROS). ROS production is increased when the electron flow in the respiratory chain (RC) is impaired. Inhibition of the RC to certain extent can be tolerated in in situ mitochondria without definite ROS formation. The capacity to generate ROS and the threshold inhibition at which ROS production starts to increase significantly are different for complex I, II and IV, respectively. Inhibition of complex I to a small degree is sufficient to increase ROS production, whereas both complex III and IV could be inhibited by about 70% without an increase in ROS formation. Dissipation of mitochondrial membrane potential fails to prevent ROS formation induced by inhibition of respiratory complexes. ROS, at the same time, inhibits a number of mitochondrial enzymes playing an important role in the energy production. Inhibition of alpha‐ketoglutarate dehydrogenase could limit the formation of NADH. The most sensitive enzyme to ROS is aconitase, which is a sensitive marker of in situ ROS generation.
Docosahexaenoic acid accumulation in the prenatal brain: a purported role in combating oxidative stress
Authors: Yavin E. , Green P. , Brand A.
Published: May 2003

Harmful reactive oxygen species (ROS) and their byproducts generated during normal physiological activity are maintained at low levels due to a counteracting antioxidant defense mechanism that involves several enzymes and low molecular weight reducing compounds. Docosahexaenoic acid (DHA, n‐3, 22:6) is a polyunsaturated fatty acid that has been shown in model membranes to serve as target for ROS and form lipid hydroperoxides (LHO). In brain tissue DHA may be particularly susceptible to ROS, nevertheless certain experimental results indicate no change or even decreased LHO following DHA or other n‐3 fatty acid supplements (1). The possibility that DHA in association with the vinyl ether bond of plasmalogens may subserve as an antioxidant will be evaluated in the prenatal brain at the time when a highly selective rise of DHA has been found (2).
TRV1 involvement in inflammatory pain: mechanisms and pharmacological modulation
Authors: Morenilla‐Palao C. , Planells‐Cases R. , García‐Martínez C. , Garcia‐Sanz N. , Ferrer‐Montiel A.
Published: May 2003

Vanilloid receptor I (TRPV1) is an integral membrane protein that integrates thermal and chemical stimuli. This molecular device is at the essence of cellular signalling at peripheral nerve terminals where it plays a central role in nociception. As expected, channel dysfunction is critically involved in pain transduction, specially in inflammatory pain. This notion is supported by genetic and pharmacological knock out data. As other ion channels, TRPV1 is a component of supramolecular assemblies that configure intraneuronal protein networks essential for signal transduction. As a result, a tremendous effort is being invested to identify the molecular components of the ion channel complex, and to validate them as therapeutic targets for better analgesic drugs. Current advances and discoveries in this exciting field will be highlighted, along with their implications for efficient and selective pain management.