Search results for "Brain chemistry"

Neuroglobin and cytoglobin: fresh blood to the vertebrate globin family

2002

Neuroglobin and cytoglobin are two recently discovered members of the vertebrate globin family. Both are intracellular proteins endowed with hexacoordinated heme-Fe atoms, in their ferrous and ferric forms, and display O2 affinities comparable with that of myoglobin. Neuroglobin, which is predominantly expressed in nerve cells, is thought to protect neurons from hypoxic–ischemic injury. It is of ancient evolutionary origin, and is homologous to nerve globins of invertebrates. Cytoglobin is expressed in many different tissues, although at varying levels. It shares common ancestry with myoglobin, and can be traced to early vertebrate evolution. The physiological roles of neuroglobin and cytog…

Glutathione metabolism in primary astrocyte cultures: flow cytometric evidence of heterogeneous distribution of GSH content.

1993

The time-course of intracellular glutathione (GSH) values after incubation with L-buthionine-(S,R)-sulfoximine (BSO), a selective inhibitor of gamma-glutamylcysteine synthetase, showed that glutathione turns over with a half-life of 5 h. Intracellular GSH was assayed by flow cytometry using three different methods. Astrocytes showed a narrow range of cellular size but a wide range of intracellular GSH. This heterogeneity was resolved into three distinct subpopulations which represent 20%, 35% and 45% of the total astrocyte number. The less abundant subpopulation had the lower GSH content, while the most abundant was the subpopulation with the higher content. Over 95% of astrocytes were in t…

Single-dose ebselen does not afford sustained neuroprotection to rats subjected to severe focal cerebral ischemia

2004

Oxygen free radicals have been involved in the pathophysiology of cerebral ischemia, especially after spontaneous or thrombolytic reperfusion. In this study with rats, we have combined a severe focal ischemic insult (2 h) and a prolonged reperfusion time (7 days) to assess the possible sustained neuroprotective effect of ebselen (10 or 100 mg/kg), a small, lipophilic organoselenium compound which mimics glutathione peroxidase. Parietal cortical perfusion was measured by laser-Doppler flowmetry, and focal cerebral ischemia was carried out by the intraluminal thread method. We have measured plasma selenium levels, brain reduced glutathione levels, as a marker of oxidative stress, and infarct …

Prenatal cocaine exposure alters spontaneous and cocaine-induced motor and social behaviors.

2005

The abuse of cocaine in pregnant women could affect emotional behaviors in their descendents. The aim of this work was to evaluate the effects of prenatal cocaine exposure on spontaneous and cocaine-induced motor and social behaviors in mice. Three kinds of prenatal treatment were used: non-treated animals; mice treated daily with physiological saline during the last week of pregnancy; and finally, those treated with cocaine (25 mg/kg) during the same period. Behavioral studies took place on adult males, which were housed in two different conditions: grouped (non-aggressive), or isolated (aggressive). Cocaine-pretreated animals exhibited slight differences in spontaneous motor activity, but…

Changes in selected biochemical parameters in the brain of the fish, Anguilla anguilla (L.), exposed to lindane.

1991

Influence of Age on Cerebral Housekeeping Gene Expression for Normalization of Quantitative Polymerase Chain Reaction after Acute Brain Injury in Mice

2015

To prevent methodological errors of quantitative PCR (qPCR) normalization with reference genes is obligatory. Although known to influence gene expression, impact of age on housekeeping gene expression has not been determined after acute brain lesions such as traumatic brain injury (TBI). Therefore, expression of eight common control genes was investigated at 15 min, 24 h, and 72 h after experimental TBI in 2- and 21-month-old C57Bl6 mice. Expression of β2-microglobulin (B2M), β-actin (ActB), and porphobilinogen deaminase (PBGD) increased after TBI in both ages. β2M demonstrated age-dependent differences and highest inter- and intragroup variations. Expression of cyclophilin A, glyceraldehyd…

No association of alcohol dependence with a NMDA-receptor 2B gene variant

2003

Soluble N-ethylmaleimide-sensitive-factor attachment protein and N-ethylmaleimide-insensitive factors are required for Ca2+-stimulated exocytosis of …

1996

Ca2+ stimulates exocytosis in permeabilized insulin-secreting cells. To investigate the putative cytosolic components involved in the Ca2+ response, HIT-T15 cells (a pancreatic B-cell line) were permeabilized with streptolysin-O, a procedure that allows rapid exchange of soluble components including macromolecules. We found that in this cell preparation the secretory response to Ca2+ but not to guanosine 5'-[gamma-thio]triphosphate was lost as a function of time and could be restored by rat brain cytosol in a concentration-dependent manner. Reconstitutive activity of rat brain cytosol was found in a high-molecular-mass heat-labile partially N-ethylmaleimide(NEM)-sensitive fraction. The NEM-…

Apprehending ganglioside diversity: a comprehensive methodological approach

2015

Gangliosides make a wide family of glycosphingolipids ubiquitously expressed in mammalian tissues and particularly abundant in the brain and nervous system. They exhibit a huge diversity due to structural variations in both their oligosaccharidic chain and ceramide moiety, which represent a real analytical challenge. Since their discovery in the 1940s, methods have persistently improved until the emergence of Liquid Chromatography/Mass Spectrometry (LC/MS) which offers a high level of specificity and sensitivity and is suitable with high-throughput profiling studies. We describe here a comprehensive approach relying on various techniques and aiming at fully characterizing gangliosides in bi…

NAIP-deltaEx10-11: a novel splice variant of the apoptosis inhibitor NAIP differently expressed in drug-sensitive and multidrug-resistant HL60 leukem…

2002

Alterations of neuronal apoptosis inhibitory protein (NAIP), a member of the inhibitory of apoptosis protein (IAP) family of inhibitors of apoptosis, have been previously associated with different neurodegenerative disorders. This study indicated the existence of a novel NAIP splice variant. This isoform, NAIP-deltaEx10-11, was found in tumor cell lines of different origin and in normal adult brain. Analysis of the putative protein predicted that the NAIP variant lacks part of the third BIR domain as well as the COOH-terminal tail of regular NAIP. This might suggest that it is endowed with a reduced antiapoptotic activity. This view is supported by the fact that NAIP-deltaEx10-11 mRNA and p…