Podwójne znakowanie immunologiczne CD133 i Ki-67 wskazuje na ich istotną współlokalizację w podtypie włóknistym oponiaków

Background and purpose A unique molecular and/or cellular marker for meningiomas, the most common intracranial tumours, has not been identified yet. Material and methods We investigated the co-localization fraction of CD133/Ki-67 in meningioma tissue array slide composed of 80 meningioma tissue samples of various histological variants. CD133 – a cell membrane stem cell marker – was previously proved to be associated with the initiation and progression of intracerebral gliomas and medulloblastomas. Results Immunohistochemical co-localization of CD133/Ki-67 was significantly higher in fibroblastic variant than in meningothelial and transitional subtypes. However, since there were only 3 atypical and 1 malignant meningioma spots in the tumour tissue array slide, it is difficult to draw a firm conclusion regarding the actual co-localization percentage and persistence of CD133/Ki-67 in atypical and malignant meningiomas. Conclusions Far higher co-staining percentage of CD133/Ki-67 in fibroblastic meningioma samples compared to meningothelial subtype, a histological meningioma variant, architectonically resembling the non-neoplastic meningeal cells, gave us the impression that CD133 may play a role in the formation and progression of fibroblastic meningioma variants. The persistency and the validity of this finding need to be verified by further histopathological and molecular research in order to clarify the possible role of CD133 in meningiogenesis.Wstęp i cel pracy Nie określono dotąd unikalnego znacznika molekularnego lub komórkowego dla oponiaków, najczęstszych guzów wewnątrzczaszkowych. Wcześniej wykazano, że CD133 – znacznik błony komórkowej komórek macierzystych – jest związany z zapoczątkowaniem, a także wzrostem wewnątrzczaszkowych glejaków i rdzeniaków płodowych. Materiał i metody Zbadano odsetek współlokalizacji CD133/Ki-67 w zestawach macierzy tkankowych oponiaków, złożonych z próbek 80 rozmaitych odmian histologicznych oponiaków. Wyniki Immunohistochemiczna współlokalizacja CD133 i Ki-67 była stwierdzana istotnie częściej w podtypie włóknistym oponiaka niż w podtypach meningotelialnym lub przejściowym. Ze względu na małą liczbę preparatów opo-niaków atypowych (3) oraz złośliwych (1) w badanej macierzy tkankowej trudno wyciągnąć jednoznaczne wnioski dotyczące rzeczywistego odsetka współlokalizacji i utrzymywania się CD133/Ki-67 w oponiakach atypowych i złośliwych. Wnioski Znacząco większy odsetek wspólnie występującej reaktywności CD133/Ki-67 w preparatach oponiaka włóknistego w porównaniu z podtypem meningotelialnym, którego architektonika przypomina nienowotworowe komórki opon, sprawia wrażenie, że CD133 może odgrywać rolę w powstawaniu i rozwoju oponiaków włóknistych. Trafność tego spostrzeżenia wymaga weryfikacji w dalszych badaniach histopatologicznych i molekularnych w celu wyjaśnienia możliwej roli CD133 w powstawaniu oponiaków

Neuronal nitric oxide synthase phosphorylation induced by docosahexaenoic acid protects dopaminergic neurons in an experimental model of Parkinson’s disease

Introduction. Docosahexaenoic acid (DHA) has been shown to have beneficial effects on Parkinson’s disease(PD). The aim of this study was to investigate if the DHA acts on neurons of substantia nigra (SN) by phosphorylation of neuronal nitric oxide synthase (nNOS) in an experimental mouse model of PD.Material and methods. An experimental model of PD was created by intraperitoneal injections (4 × 20 mg/kg)of the neurotoxin 1-methyl-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP). Three-month-old male C57BL/6 micewere randomly divided into four groups as follows: control (C), DHA-treated (DHA), MPTP-injected (MPTP)and DHA-treated and MPTP-injected (DHA + MPTP). DHA (36 mg/kg/day) was administered daily by gavagefor four weeks. Motor activity of the mice was evaluated with pole, locomotor activity and rotarod tests. Caspase-3activity, nitrate/nitrite and 4-hydroxynonenal (4-HNE) levels were determined by spectrophotometric assays.Immunohistochemistry was used to localize and assess the expressions of tyrosine hydroxylase (TH), nNOS andphospho-nNOS (p-nNOS) in SN.Results. An increased return and total down time in the MPTP group was observed in the pole test, while DHAtreatment decreased both parameters. The ambulatory activity, total distance and total locomotor activities weredecreased in the MPTP group, whereas they were increased by DHA treatment. MPTP-treated animals exhibitedshorter time on the rod test which was significantly increased by DHA treatment. DHA administration significantlydecreased 4-HNE and nitrate/nitrite levels of SN supernatants and protected the TH (+) dopaminergicneurons of SN in the DHA + MPTP group compared to the MPTP group. DHA treatment significantly decreasednNOS and increased p-nNOS immunoreactivities in the DHA + MPTP group compared to the MPTP group.Conclusions. These results indicate that DHA treatment protects dopaminergic neurons in SN via increasingnNOS serine 852 phosphorylation in the experimental mice model of PD

Effects of excess vitamin B6 intake on cerebral cortex neurons in rat: an ultrastructural study

The aim of this study was to investigate whether excess of vitamin B6 leads to ultrastructural changes in cerebral cortex of forty-eight healthy albino rats which were included in the study. Saline solution was injected to to the control groups (CG-10, n=12 for 10 days; CG-15, n=12 for 15 days; CG-20, n=12 for 20 days). The three experimental groups (EG-10, n=12; EG-15, n=12; EG-20, n=12) were treated with 5 mg/kg vitamin B6 daily for 10 days (EG-10), 15 days (EG-15) and 20 days (EG-20). Brain tissues were prepared by glutaraldehyde-osmium tetroxide double fixation for ultrastructural analysis. No significant changes were observed in the control groups. The ultrastructural analysis revealed that the numbers of damaged mitochondria, lipofuscin granules and vacuoles were significantly higher in all the experimental groups than in the control groups (

The effects of docosahexaenoic acid on glial derived neurotrophic factor and neurturin in bilateral rat model of Parkinson's disease.

Parkinson's disease (PD) is the second most common neurodegenerative disorder marked by cell death in the Substantia nigra (SN). Docosahexaenoic acid (DHA) is the major polyunsaturated fatty acid (PUFA) in the phospholipid fraction of the brain and is required for normal cellular function. Glial cell line derived neurotrophic factor (GDNF) and neurturin (NTN) are very potent trophic factors for PD. The aim of the study was to evaluate the neuroprotective effects of GDNF and NTN by investigating their immunostaining levels after administration of DHA in a model of PD. For this reason we hypothesized that DHA administration of PD might alter GDNF, NTN expression in SN. MPTP neurotoxin that induces dopaminergic neurodegeneration was used to create the experimental Parkinsonism model. Rats were divided into; control, DHA-treated (DHA), MPTP-induced (MPTP), MPTP-induced+DHA-treated (MPTP+DHA) groups. Dopaminergic neuron numbers were clearly decreased in MPTP, but showed an increase in MPTP+DHA group. As a result of this, DHA administration protected dopaminergic neurons as shown by tyrosine hydroxylase immunohistochemistry. In the MPTP+DHA group, GDNF, NTN immunoreactions in dopaminergic neurons were higher than that of the MPTP group. In conclusion, the characterization of GDNF and NTN will certainly help elucidate the mechanism of DHA action, and lead to better strategies for the use of DHA to treat neurodegenerative diseases

Molecular Cytogenetic Analysis and Resequencing of Contactin Associated Protein-Like 2 in Autism Spectrum Disorders

Autism spectrum disorders (ASD) are a group of related neurodevelopmental syndromes with complex genetic etiology.1 We identified a de novo chromosome 7q inversion disrupting Autism susceptibility candidate 2 (AUTS2) and Contactin Associated Protein-Like 2 (CNTNAP2) in a child with cognitive and social delay. We focused our initial analysis on CNTNAP2 based on our demonstration of disruption of Contactin 4 (CNTN4) in a patient with ASD;2 the recent finding of rare homozygous mutations in CNTNAP2 leading to intractable seizures and autism;3 and in situ and biochemical analyses reported herein that confirm expression in relevant brain regions and demonstrate the presence of CNTNAP2 in the synaptic plasma membrane fraction of rat forebrain lysates. We comprehensively resequenced CNTNAP2 in 635 patients and 942 controls. Among patients, we identified a total of 27 nonsynonymous changes; 13 were rare and unique to patients and 8 of these were predicted to be deleterious by bioinformatic approaches and/or altered residues conserved across all species. One variant at a highly conserved position, I869T, was inherited by four affected children in three unrelated families, but was not found in 4010 control chromosomes (p = 0.014). Overall, this resequencing data demonstrated a modest nonsignificant increase in the burden of rare variants in cases versus controls. Nonethless, when viewed in light of two independent studies published in this issue of AJHG showing a relationship between ASD and common CNTNAP2 alleles,4,5 the cytogenetic and mutation screening data suggest that rare variants may also contribute to the pathophysiology of ASD, but place limits on the magnitude of this contribution

Melatonin Does Not Alter Cell Proliferation in Metastatic Breast Cancer Cells

Breast cancer treatments continue to be investigated with supported by new treatment methods. Melatonin is a hormone that can be effective in the treatment of breast cancer due to its anti-oxidant effect. Melatonin had previously shown to inhibit proliferation of cancer cells. In this study, we aimed to determine the effect of melatonin on the proliferation of metastatic breast cancer cells in comparison to doxorubicin, a well-known chemotherapeutic agent. Doxorubicin inhibited proliferation of metastatic breast cancer cells while melatonin has no effect. We are currently examining the effects of melatonin and doxorubicin combination therapy on metastatic breast cancer cells

CCM2 and CCM3 proteins contribute to vasculogenesis and angiogenesis in human placenta

Placenta as an ideal model to study angiogenic mechanisms have been established in previous studies. There are two processes, vasculogenesis and angiogenesis, involved in blood vessel formation during placental development. Therefore, blood vessel formation is a crucial issue that might cause vascular malformations. One of the vascular malformations is cerebral cavernous malformation (CCM) in the central nervous system, consisting of endothelium-lined vascular channels without intervening normal brain parenchyma. Three CCM loci have been mapped as Ccm1, Ccm2, Ccm3 genes in CCM. In order to investigate whether CCM proteins participate in blood vessel formation, we report here the expression patterns of CCM2 and CCM3 in developing and term human placenta by means of immunohistochemistry and Western blot analysis. CCM2 and CCM3 were obviously detected in the vascular endothelium during early pregnancy. Moreover, vascular endothelium of stem villi revealed a moderate immunostaining for CCM2 and, to a lesser extent, in the endothelium of mature intermediate villi in term placenta. Interestingly, CCM3 immunostaining was weakly localized in the endothelium of mature intermediate villi and showed lesser expression going toward stem villi in term placenta. The expression patterns of the proteins were clearly identified in the vascular endothelium of human placenta, suggesting that they might play roles during angiogenesis and vasculogenesis. Furthermore, with this study, CCM2 and CCM3 have been described for the first time in the human placenta

Changes in the brain cortex of rabbits on a cholesterol-rich diet following supplementation with a herbal extract of Tribulus terrestris

Extracts of the medicinal herb Tribulus terrestris (TT) are used for treating various diseases. The saponins, a component of TT, play a role in regulating blood pressure and in treatment of hyperlipidemia. The aim of the study was to investigate the immunohistochemical and ultrastructural alterations in the cerebral cortex of experimental rabbits on a cholesterol rich diet treated with TT. The rabbits were divided into three groups and followed for 12 weeks as control group (CG); experimental group I (EG-I), fed with a cholesterol-rich diet; experimental group II (EG-II), treated with an extract of TT (5mg/kg/day) after a cholesterol-rich diet of 4 weeks. In EG-I there were ultrastructural changes, including mitochondrial degeneration, increased lipofuscin pigments, myelin sheath damage with axoplasmic shrinkage and electron dense granules in the neurovascular unit. The number of synapses apparently decreased in both experimental groups. Administration of TT extract in EG-II led to marked ultrastructural alterations in neurons, including decreased mitochondrial degeneration (P<0.001) and extensive oedematous areas in the neurovascular unit. However, in EG-II, lamellar myelin, axonal structures and mitochondria were well protected. These alterations possibly indicate that saponins have an effect on the neurons either directly or by its conversion to steroidal saponins. Therefore, these findings add further evidence supporting the protective claims of TT in cerebral architecture in dietary induced hyperlipidemia