Developmental changes in nitric oxide synthase protein expression in the rat striatum and cerebral cortex

We examined the expression of brain nitric oxide synthase (bNOS) in two developing rat brain structures, the striatum and the cerebral cortex. For this purpose, we quantified the relative protein concentration level using the Western blotting method and densitometric scanning. 32 Wistar rats, divided according to survival period (P0-P120-postnatal days) were used in this study. Our results demonstrate that bNOS expression rises in these structures during the first week of postnatal life, reaching a maximum in the striatum on the 10th day and in the cerebral cortex on the 7th day of postnatal life. After the period of increase the expression declines and after the 14th day a stabilisation of bone protein concentration is observed, both in the striatum and the cerebral cortex. These changes in bone protein expression might be related to the important role of nitric oxide in the developing rat brain, especially in synaptogenesis, apoptosis and neurotransmission

Co-existence of apoptotic and necrotic features within one single cell as a result of menadione treatment

In the present study we examined the effects of menadione, a redox cycling agent, on structural changes of human osteosarcoma line 143B cells. It has been previously reported that menadione can cause necrotic or apoptotic cell death in a concentration- depending manner. In our experimental model, cells were treated with 100 μM menadione for 24 hours. Using electron microscopy technique cells carrying three kinds of morphological changes were detected: necrotic cells, apoptotic cells and those demonstrating a co-existence of apoptotic and necrotic features in one single cell

Fast perinuclear clustering of mitochondria in oxidatively stressed human choriocarcinoma cells

Mitochondrial dysfunction plays a crucial role in cell types that exhibit necrosislike death after activation of their death program. Tumour necrosis factor (TNF) induces abnormal, perinuclear clustering of mitochondria from an evenly spread distribution throughout the cytoplasm. The mitochondria withdraw from the cell periphery and aggregate in a unipolar perinuclear cluster. TNF-induced mitochondrial clustering is caused by impaired kinesin-mediated transportation of mitochondria. In this report, we describe a novel activity of menadione (MEN), namely the induction of an altered spatial distribution of mitochondria in the choriocarcinoma JAR cells. Strikingly, 2 hours of cell exposition to menadione did not disrupt the integrity of the plasma membrane, while the intracellular ATP level significantly decreased. Control (untreated) cells displayed a typically scattered distribution of filamentary mitochondria inside the cell. After 2 hours of MEN treatment the spatial distribution of the mitochondria was markedly altered to an asymmetric perinuclear clustered distribution. Menadione-stressed cells displayed a highly asymmetrical perinuclear clustered distribution of the mitochondria. The exposure of cells to MEN also results in a change in shape of the mitochondria into a population of enlarged granular structures. The results of our study demonstrate that in JAR cells menadione causes mitochondria to translocate from the cell periphery into the perinuclear region several hours before disruption of cell membrane integrity and cell death

A rare variations of the cephalic vein drainage: two cases report

Throughout the years, anatomic studies have demonstrated numerous variations in the course of the cephalic vein (CV). There are, however, very rare cases of uncommon formation, course or termination of the vein to which our attention should be drawn. During a routine dissections conducted in the Department of Anatomy and Neurobiology, in two formalin-fixed cadavers, the very rare anatomical variants were found. In 80 year-old Caucasian female the right cephalic vein, after crossing the clavipectoral triangle, ascended anterior and superior to the clavicle and drained into the lateral branch of the right external jugular vein, which in turn opened to the right subclavian vein. In the second case, the dissection of 83 year-old Caucasian male cadaver revealed that after passing through the deltopectoral groove, the left cephalic vein run between clavicle and subclavius muscle to terminate in the left subclavian vein. Understanding of the topography, morphology and anatomical variations of the cephalic vein is important not only for the anatomists but for the clinicians and nurses as well. Such knowledge can prevent multiple complications during many invasive procedures including implantation of Cardiac Implantable Electronic Devices, central venous access, arteriovenous fistula creation or even iatrogenic injuries during clavicle or glenohumeral joint surgery

The morphology of the ependymal rosettes.

<p>Microscopic view of the ependymal rosettes formed at the ventral part of right lateral ventricle. Sections of the rat brains at 8 weeks after the administration of the studied substances are shown: A—DMSO, B—MG-132, and C—epoxomicin. Staining—Nissl method; scale bar = 100 μm.</p

Morphological Changes within the Rat Lateral Ventricle after the Administration of Proteasome Inhibitors

<div><p>The broad variety of substances that inhibit the action of the ubiquitin-proteasome system (UPS)—known as proteasome inhibitors—have been used extensively in previous studies, and they are currently frequently proposed as a novel form of cancer treatment and as a protective factor in intracerebral hemorrhage treatment. The experimental data on the safest route of proteasome inhibitor administration, their associated side effects, and the possible ways of minimizing these effects have recently become a very important topic. The aim of our present study was to determine the effects of administering of MG-132, lactacystin and epoxomicin, compounds belonging to three different classes of proteasome inhibitors, on the ependymal walls of the lateral ventricle. Observations were made 2 and 8 weeks after the intraventricular administration of the studied substances dissolved in dimethyl sulfoxide (DMSO) into the lateral ventricle of adult Wistar rats. Qualitative and quantitative analysis of brain sections stained with histochemical and inmmunofluorescence techniques showed that the administration of proteasome inhibitors caused a partial occlusion of the injected ventricle in all of the studied animals. The occlusion was due to ependymal cells damage and subsequent ependymal discontinuity, which caused direct contact between the striatum and the lateral nuclei of the septum, mononuclear cell infiltration and the formation of a glial scar between these structures (with the activation of astroglia, microglia and oligodendroglia). Morphologically, the ubiquitin-positive aggregates corresponded to aggresomes, indicating impaired activity of the UPS and the accumulation and aggregation of ubiquitinated proteins that coincided with the occurrence of glial scars. The most significant changes were observed in the wall covering the striatum in animals that were administered epoxomicin, and milder changes were observed in animals administered lactacystin and MG-132. Interestingly, DMSO administration also caused damage to some of the ependymal cells, but the aggresome-like structures were not formed. Our results indicate that all of the studied classes of proteasome inhibitors are detrimental to ependymal cells to some extent, and may cause severe changes in the ventricular system. The safety implications of their usage in therapeutic strategies to attenuate intracerebral hemorrhagic injury and in brain cancer treatment will require further studies.</p></div

The ubiquitin-positive aggregates within the cells of subventricular area.

<p>The localization of the ubiquitin-positive aggregates in the cells of striatum after the administration of A—DMSO and B, C—epoxomicin is shown. The arrow points to the clusters of ubiquitin-positive aggregates in astrocytes, while the arrowheads indicate small ubiquitin inclusions in cells that are not astrocytes. Scale bars: A, B—50 μm; C—25 μm.</p

Glial scar formation in the lateral ventricle.

<p>Glial activation in the striatum (Str) and glial scar formation 2 weeks after the administration of DMSO (A) and epoxomicin (B) into the right lateral ventricle (LV). An anti-GFAP antibody was used as a marker of astroglia, an anti-NogoA antibody was used as a marker of oligodendroglia, and Neuro Trace Red stained the neuronal bodies and nuclei of both the vascular endothelial cells and glial cells. Scale bar—50 μm.</p

Evolution of the morphological changes within the rat lateral ventricle at 2 and 8 weeks after the administration of the studied substances.

<p>Microscopic view of the morphological changes (glial scar, mononuclear cells infiltration) associated with the adhesion area within lateral ventricle; a comparison of the view from coronal sections of the brains from the representative rats at 2 and 8 weeks after the administration of the studied substances– DMSO, MG-132, lactacystin and epoxomicin. Staining—Nissl method; scale bar = 100 μm.</p