French maritime pine bark treatment decelerates plaque development and improves spatial memory in Alzheimer's disease mice.

BACKGROUND: Plant extracts are increasingly investigated as potential drugs against Alzheimer's disease (AD) and dementia in general. Pycnogenol is an extract from the bark of the French maritime pine (Pinus pinaster Aiton subsp. atlantica) with known anti-oxidative and neuroprotective effects. HYPOTHESIS/PURPOSE: Pycnogenol is thought to improve cognitive functions in elderly. We wanted to investigate and quantify these effects in a model system of cerebral ß-amyloidosis/AD. STUDY DESIGN/METHODS: This study experimentally assessed the effects of Pycnogenol on AD-related pathology in a ß-amyloidosis mouse model. APP-transgenic mice and controls were treated orally in a pre-onset and post-onset treatment paradigm. The effects of Pycnogenol were characterized by analysing ß-amyloid (Aß) plaques, number of neurons, glia coverage, myelination pattern, and cortical coverage with axons using immunohistochemistry. Aß levels were quantified using ELISA and gene expression levels of APP-processing enzymes ADAM10, BACE1 and IDE protein levels were determined by Western blot. Behavioural changes in circadian rhythm were monitored and spatial memory / cognition was assessed using a water maze test. RESULTS: Pycnogenol significantly decreased the number of plaques in both treatment paradigms but did not alter levels of soluble Aß or the gene expression of APP-processing enzymes. The morphological analyses revealed no changes in the number of neurons, astrocytes, microglia, the myelination pattern, or the morphology of axons. Behavioural testing revealed an improvement of the spatial memory in the pre-onset treatment paradigm only. CONCLUSION: Our results suggest to evaluate clinically a potential use of Pycnogenol in the prevention or in early stages of mild cognitive impairment (MCI) and AD.

Spinal cord pathology in chronic experimental Toxoplasma gondii infection.

Infection with the protozoan Toxoplasma (T.) gondii causes chronic infection of the central nervous system and can lead to life-threatening encephalomyelitis in immunocompromised patients. While infection with T. gondii has long time been considered asymptomatic in immunocompetent hosts, this view is challenged by recent reports describing links between seropositivity and behavioral alterations. However, past and current researches are mainly focused on the brain during Toxoplasma encephalitis, neglecting the spinal cord as a key structure conveying brain signals into motion. Therefore, our study aimed to fill the gap and describes the spinal cord pathology in an experimental murine model of toxoplasmosis. In the spinal cord, we found distinct histopathological changes, inflammatory foci and T. gondii cysts similar to the brain. Furthermore, the recruitment of immune cells from the periphery was detected. Moreover, resident microglia as well as recruited monocytes displayed an increased MHC classes I and II expression. Additionally, the expression of pro- and anti-inflammatory cytokines was enhanced in the brain as well as in the spinal cord. In summary, the pathology observed in the spinal cord was similar to the previously described changes in the brain during the infection. This study provides the first detailed description of histopathological and immunological alterations due to experimental T. gondii induced myelitis in mice. Thus, our comparison raises awareness of the importance of the spinal cord in chronic T. gondii infection.

Evaluation of systemic targeting of RET oncogene-based MTC with tumor-selective peptide-tagged Ad vectors in clinical mouse models.

Significant advantage of targeted antitumoral treatment consists in the possibility to restrict maximum therapeutic efficacy to the malignant cell population by reducing toxicity in healthy tissues. Using different clinical models for aggressive medullary thyroid carcinoma (MTC), we have recently identified peptide ligands that bind highly selective to tumor cells. By linking the most convincing SRESPHP peptide to an adenoviral (Ad) vector expressing the MTC-related oncogene inhibitor RETΔTK, gene transfer was specifically directed to neoplastic tissue after systemic virus administration. We show that peptide-mediated delivery of RETΔTK significantly enhanced apoptosis, resulting in a strong inhibition of orthotopic and xenograft tumor growth. Conversely, tumors treated with controls expanded their initial size without notable cell death. According to the therapeutic effect, strong virus accumulation was found exclusively in thyroid carcinomas. Strikingly, application of native tropism depleted viral vector linked to tumor-selective peptide was accompanied by a substantial reduction of Ad binding to the liver. Of note, single systemic injection of a low dose (10e8 pfu/mouse) of MTC-specific Ad.RETΔTK induced regression of multiple tumors at different sites in all treated animals. In sum, our results open up the possibility for an efficient cancer cell-specific therapy of primary MTC, their migrating populations and potentially metastases.

[Gastrointestinal stromal tumor (GIST) of the anterior rectal wall. R0 resection with simultaneous radical retropubic prostatectomy]. / Gastrointestinaler Stromatumor (GIST) der vorderen Rektumwand. R0-reseziert bei simultaner radikaler retropubischer Prostatektomie.

This case report deals with a 79-year-old patient with a gastrointestinal stromal tumor (GIST) of the anterior rectal wall which was unusually located between the rectum and the prostate gland. In addition, this patient suffered from subvesical obstruction accompanied by an elevated PSA level. These circumstances led to our decision to operate on the tumor via simultaneous radical retropubic prostatectomy. In our opinion this resection technique was easier and less traumatic for the patient compared to procedures performed via the abdomen and perineum. This case report demonstrates that in the case of tumors located between the rectum and the prostate gland the differential diagnosis should include not only prostate carcinoma but also rare tumor entities such as GIST.

[The role of blood-brain barrier in the pathogenesis of Alzheimer dementia--implications for immunological therapies for plaque dissolution]. / Die Funktion der Blut-Hirn-Schranke für die Pathogenese der Alzheimer-Demenz--Implikationen für immunologische Therapien zur Plaqueauflösung.

Alzheimer's disease (AD) is a devastating neurodegenerative disorder affecting more than 27 million people worldwide and leading to severe social-economic problems. One characteristic hallmark of AD--the amyloid plaques--are still being discussed to be one important triggering factor. However, current animal and autopsy studies refer to soluble and highly toxic A block oligomers as the deadly agent for the neurons. Current therapies mainly rely on the abatement of symptoms without antagonizing the etiology of the disease. Potential new approaches address reduced production, increased degradation and/or evacuation of toxic A block peptides from the brain. Among others one important group of target-proteins are the ABC transporters of the blood-brain barrier which contribute importantly to the detoxification of the brain. Changes of specific transport functions evoke important alterations for the known pathogenesis and future therapies of AD, especially approaches that target plaque dissolution and plaque reduction.

[Involvement of CNS in leukaemia and lymphomas--CSF meningeosis and immunocytochemical phenotyping]. / ZNS-Beteiligung bei Leukämien und Lymphomen--Meningeosis im Liquor cerebrospinalis und Möglichkeiten der immunzytochemischen Zellphänotypisierung.

The detection of tumour cells in the cerebrospinal fluid (CSF) of leukaemia and lymphoma patients is a challenge for CSF cytological investigation. Nevertheless, it is generally possible to confirm the involvement of the central nervous system (CNS) by conventional microscopic detection of tumour cells. Immunocytochemical staining techniques are a valuable complement of conventional cytology. Immunocytochemical cell phenotyping is indicated for identification of atypical cells in patients with suspected primary CNS lymphoma or malignant haematological disease.

Transcriptome analysis in mouse tumors induced by Ret-MEN2/FMTC mutations reveals subtype-specific role in survival and interference with immune surveillance.

Activating mutations in the Ret proto-oncogene are responsible for occurrence of multiple endocrine neoplasia (MEN) type 2A and 2B, and familial medullary thyroid carcinoma (FMTC). A striking genotype-phenotype correlation between the mutated RET codon and clinical manifestation implies that tumorigenesis is conditioned by the type of mutation. We investigated gene expression profiles between and within distinct MEN2 subtypes through whole-genome microarray analysis in tumors induced by NIH-3T3 cells transformed with defined RET-MEN2A (C609Y, C634R), MEN2B, (A883F, M918T), and FMTC (Y791F) mutations. Expression profiling identified a statistically significant modification of 1494 genes, 628 down- and 866 upregulated in MEN2B compared with MEN2A/FMTC tumors. By contrast, no obvious alterations were observed among individual MEN2B and MEN2A type mutations, or between MEN2A and FMTC. Functional clustering of differential genes revealed RET-MEN2B specific upregulation of genes associated with novel growth and survival pathways. Intriguingly, RET-MEN2A/FMTC-specific tumors were characterized by a considerable number of genes involved in the host antitumor immune response via stimulation of natural killer/T-cell proliferation, migration, and cytotoxicity, which were completely absent in RET-MEN2B related cancers. QPCR on tumors versus cultured NIH-RET cell lines demonstrated that they are largely attributed to the host innate immune system, whereas expression of CX3CL1 involved in leukocyte recruitment is exclusively RET-MEN2A/FMTC tumor cell dependent. In correlation, massive inflammatory infiltrates were apparent only in tumors carrying MEN type 2A/FMTC mutations, suggesting that RET-MEN2B receptors specifically counteract immune infiltration by preventing chemokine expression, which may contribute to the different clinical outcome of both subtypes.

Expression of multidrug transporters in dysembryoplastic neuroepithelial tumors causing intractable epilepsy.

OBJECTIVE: Dysembryoplastic neuroepithelial tumors (DNT) are relatively benign brain lesions that often cause medically intractable epilepsy. There is mounting evidence that multidrug transporters such as P-glycoprotein (P-gp) or multidrug resistance-associated proteins (MRP) play an important role in the development of resistance to antiepileptic drugs (AED). MATERIAL AND METHODS: In the present study, we examined the expression of several multidrug transporters in 14 cases of DNT. The peritumoral brain tissue as well as 9 cases of arteriovenous malformations (AVM) served as controls. P-gp, MRP2, MRP5 and breast cancer resistance protein (BCRP) expression was evaluated qualitatively and quantitatively using immunohistochemistry. RESULTS: All transporters were overexpressed quantitatively in DNT, but each revealed a different labeling pattern. P-gp and BCRP were predominantly located in the endothelium of brain vessels. MRP5 was detected primarily in endothelial cells, but notably also in neurons. The expression of P-gp, MRP2 and MRP5 was low in AVM, whereas BCRP demonstrated strong staining. Examination of MDR1 gene polymorphisms revealed no correlation with P-gp expression whereas the MRP2 exon 10 G1249A polymorphism was associated with different MRP2 labelling. CONCLUSIONS: Our results show that multidrug transporters are overexpressed in DNT. This finding supports the view that several of these transport proteins may play an important role in the mechanisms of drug resistance in epileptic brain tissue.

Ceruloplasmin gene variations and substantia nigra hyperechogenicity in Parkinson disease.

BACKGROUND: Transcranial ultrasound may be used to detect increased iron levels of the substantia nigra (SN) in patients with Parkinson disease (PD) and in control subjects. It is not known whether iron accumulation in PD is a primary or secondary phenomenon. However, sequence variations in genes involved in iron metabolism have been linked to basal ganglia disorders. One of these is ceruloplasmin (Cp), which is vitally involved in iron transport across the cell membrane. METHODS: One hundred seventy-six patients with PD according to the UK Brain Bank criteria and 180 ethnically matched control subjects, who were previously examined for SN iron signal changes by transcranial ultrasound, were examined for mutations in the Cp gene using denaturing high-performance liquid chromatography and subsequent sequencing for verification of unequivocal signals. Immunohistochemistry of PD midbrains was performed to examine the presence of Cp in Lewy bodies. RESULTS: Five novel missense variations were detected. One of these (I63T) was found in a single PD patient. A known variation (D554E) was significantly associated with PD and the ultrasound marker for increased SN iron levels. Moreover, a third sequence variation (R793H) was found to segregate with the ultrasound marker for increased iron levels in patients and control subjects. Immunohistochemistry demonstrated that Cp co-localizes with Lewy bodies in PD. CONCLUSIONS: Detection of sequence variations in a single Parkinson disease (PD) patient or associated with the ultrasound marker for increased substantia nigra iron levels and the presence of ceruloplasmin (Cp) immunoreactivity in Lewy bodies underline a suspected role for Cp in the pathogenesis of PD. Further functional analyses are warranted to investigate whether these variations are causally linked to the complex pathogenesis of PD in a subset of cases.

Expression of stromelysin-1 (MMP-3), gelatinase B (MMP-9), and plasminogen activator system during fetal calvarial development.

AIMS: To investigate whether degrading proteases can be found in patent calvarial sutures. Sutural growth and fusion means replacement of the sutural connective tissue, rich in fibronectin and collagen type V, by expanding calvarial bone. Proliferation of one tissue into the border area of another implies the presence of enzymes able to degrade extracellular matrix (ECM). An important family of proteases is the matrix metalloproteinases (MMPs), as is the plasminogen/plasmin system. METHODS AND RESULTS: Expression of two MMPs with substrate specifity for fibronectin and collagen type V and of the plasminogen activator system was studied by immunohistochemistry in samples of human fetal calvariae (age range weeks 19-35 of gestation). In all cases, intense staining for MMPs, urokinase, and urokinase receptor was found in the sutural connective tissue and along the outer and inner borders of calvarial bone. CONCLUSIONS: Our findings suggest that degradation of sutural connective tissue takes place during sutural growth. This might facilitate proliferation of calvarial bone. Recently, it was shown that an important regulatory mechanism of sutural growth is apoptosis of osteoblasts in the osteogenic front. Intact fibronectin is known to prevent apoptosis of proliferating osteoblasts while fibronectin degradation induces their apoptosis.

Cerebral beta-amyloid deposition is augmented by the -491AA promoter polymorphism in non-demented elderly individuals bearing the apolipoprotein E epsilon4 allele.

The apolipoprotein E epsilon4 allele (APOE, gene; apoE, protein) is widely accepted as a risk factor for Alzheimer's disease (AD). Our previous studies found that APOEepsilon4 promotes AD pathogenesis by fostering the early deposition of the amyloidogenic peptide Abeta in the aging brain. Recent reports suggest that polymorphisms in the upstream promoter region of APOE differentially affect the production of apoE and also may have an important influence on the probability of developing AD. In this study, we asked whether APOE promoter -491 (A/T) variants interact with APOE polymorphisms to modulate the degree of beta-amyloid- and tau-related pathology in the medial temporal lobe of the non-demented elderly. Our results confirm that APOEepsilon4 is associated with increased formation of senile plaques, cerebrovascular amyloid, and neurofibrillary tangles in the medial temporal lobe. We also found that homozygosity for A at position -491 of the APOE promoter (-491AA) correlates with increased Abeta17-24 and Abeta42 deposition in APOEepsilon4-positive cases, but not in cases lacking the epsilon4 allele. In comparison, Abeta burden is significantly less in epsilon4 carriers with the -491AT and -491TT promoter allelotypes. There was no effect of -491 polymorphisms on Abeta40 deposition (which is relatively sparse in the non-demented elderly), on the number of activated microglia, or on the amount of neurofibrillary tangles. We conclude that the amyloidogenic effects of apoE4 are exacerbated by polymorphisms in the APOE promoter that enhance apoE production.

Activated microglia do not mediate the early deposition of Abeta in carriers of the apolipoprotein Eepsilon4 allele.

Activated microglia are a prominent component of the senile plaques in end-stage Alzheimer's disease, but whether microglia contribute to the initiation of the lesions remains unknown. In a previous postmortem study of non-demented elderly cases, we found that amyloidogenesis is advanced by at least 10 years in carriers of the apoEepsilon4 allele. To determine whether microglia are involved in the initial stages of beta-amyloid pathogenesis and whether apoE genotype influences microglial activation, we quantified HLA-DR-immunoreactive microglia in the medial temporal lobe of 229 non-demented humans of various APOE genotypes who had died between 50 and 91 years of age. Our results show that the number of HLA-DR-immunoreactive microglia increases with advancing age in both the gray matter and the white matter. In contrast to amyloid plaques and neurofibrillary tangles, there is no significant correlation between apoE genotype and density of microglia, although apoEepsilon4 homozygotes tended to have more microglia than did other apoE groups. In sections double-immunostained for Abeta and activated microglia, activated microglia were associated with dense-cored plaques but not with diffuse plaques, suggesting that microglial activation is a relatively late event in the genesis of beta-amyloid. Activation of microglia thus appears not to be the initial impetus for Abeta-deposition in the elderly.

Immunolocalization of urokinase and its receptor in prematurely fused cranial sutures of infants.

In cranial sutural samples derived from five children with premature cranial suture fusion we have performed immunostaining for the urokinase plasminogen activator (uPA) and urokinase receptor (uPAR). We have found a strong reactivity for cell- or matrix-bound uPA and uPAR in the sutural connective tissue and associated with the osteoblasts and osteocytes lining the calvarial bone. The sutural tissue itself showed a banding with different intensity of urokinase and uPAR staining concerning connective tissue. It is proposed that the components of the plasminogen activating system are involved in tissue turnover of sutural tissue and in sutural growth.

Treatment with nimodipine or mannitol reduces programmed cell death and infarct size following focal cerebral ischemia.

The present study was conducted to evaluate the effects of nimodipine and mannitol on infarct size and on the amount of apoptosis after transient focal cerebral ischemia. Focal cerebral ischemia was induced in male Sprague-Dawley rats (weight 300-380 g) by transient occlusion of the right middle cerebral artery (MCAO) using an intraluminal thread model. All animals underwent ischemia for 2 h, followed by 24 h of reperfusion. Group I (n=16) was untreated. Group II (n=16) received 15% mannitol (1 g/kg as bolus) and group III (n=9) received 15 microg/kg/h nimodipine intravenously beginning 15 min prior to MCAO. Twenty-four hours after reperfusion, the brain was taken and sectioned in coronal slices. The slices were stained with H&E and with the transferase dUTP nick-end labeling (TUNEL) technique. Histopathological analysis revealed a significant (P<0.05) decrease in infarct size in the striatum with both drugs: mannitol (group II) 25.4+/-5.9% and nimodipine (group III) 21.5+/-11.0% versus control (group I) 34.9+/-7.0% and in the cortex 2.7+/-2.0% (group II) and 6.3+/-2.4% (group III) versus control 14.4+/-9.0% (group I). The number of apoptotic cells was statistically lower in the therapy groups (group III 9.6, group II 25.8) versus control (group I 57.9) (Mann-Whitney-Wilcoxon U-test Z>1.96, P<0.05). This study indicates that mannitol and nimodipine provide neuroprotection by preventing both the necrotic and apoptotic components of cell death after transient focal cerebral ischemia and may be effective as neuroprotective drugs for cerebrovascular surgery.

[MR tomography study of the development of the sphenoid sinus]. / MR-tomographische Untersuchung zur Entwicklung der Keilbeinhöhle.

BACKGROUND: Aim of this study was to evaluate the postnatal growth pattern of the sphenoid sinus. PATIENTS: 83 cerebral MRI examinations of infants and children aged 5 months to 14 years were retrospectively reviewed for pneumatization and growth of sphenoid sinus. RESULTS: A continuous increase of pneumatization and growth of the sphenoid sinus was demonstrated between infancy and adolescence including considerable individual variations. Even in children less than two years old remarkable spatial extends of this sinus could be found in some cases. CONCLUSION: Diagnosis of an acute or chronical sinusitis in pediatric patients should alert the clinician to the possibility of a sphenoidal participation.

Apolipoprotein E4 promotes the early deposition of Abeta42 and then Abeta40 in the elderly.

The apolipoprotein Eepsilon4 allele (ApoEepsilon4) is associated with a selective increase in deposition of the 40-amino acid form of the beta-amyloid peptide (Abeta40) in endstage Alzheimer's disease. To determine how apoE genotype affects the early events in beta-amyloid pathogenesis, we analyzed the medial temporal lobes of 244 elderly persons who were not clinically demented using antibodies selective for the C termini of Abeta40 and Abeta42. We found that: (1) the number of both Abeta42- and Abeta40-positive senile plaques increase with age; (2) Abeta42 appears at younger ages, and in more amyloid deposits, than does Abeta40 in all ApoE groups; (3) when compared at similar ages, older persons with ApoEepsilon4 are more likely to have Abeta42- and Abeta40-immunoreactive deposits than are persons without ApoEepsilon4; (4) Abeta40-containing plaques arise at least a decade later than do Abeta42 plaques, and are seldom found in the medial temporal lobe of older persons lacking ApoEepsilon4; and (5) in the absence of overt Alzheimer's disease, cerebral amyloid angiopathy is rare in the elderly, but in our sample was significantly augmented in ApoEepsilon4 homozygotes. We conclude that ApoEepsilon4 hastens the onset of Abeta42 deposition in the senescent brain, which in turn fosters the earlier evolution of fibrillar, Abeta40-positive plaques, thereby increasing the risk of Alzheimer's disease.