Stem cells based therapy in high grade glioma: why the intraventricular route should be preferred?

AIM: Mesenchymal stem cells (MSCs) migrate in response to chemokines and possess extensive tropism for experimental glioma. Antitumor effects have been reported following intracranial and intravenous administration of gene-modified MSCs. Among the different routes for cell transplant, the intraventricular (IV) approach found very little employment in comparison with intraparenchymal, intratumoral and intravenous administration protocols. Nevertheless, IV transplantation offers advantages in terms of cells viability and distribution toward target sites, opening interesting opportunities for its clinical application. METHODS: Using a rat glioma model, we investigated migratory capacity, tumor tropism, distribution and differentiation of MSCs following IV administration. RESULTS: Transplanted MSCs create niches of viable cells in the subventricular zone and can be stimulated to migrate to sites of tumor infiltration. MSCs seemed not to be involved in tumor growth and angiogenesis. CONCLUSION: We speculate that the IV route can be used to achieve a kind of reservoir of self-renewal cells, potentially active against the spread of cancer cells. Further studies are needed to shed light on MSCs distribution close to the ventricular wall, in order to define their lifespan and their capacity to migrate towards new-enhancing foci time after implantation.

Recent therapeutic strategies for spinal cord injury treatment: possible role of stem cells.

Spinal cord injury (SCI) often results in significant dysfunction and disability. A series of treatments have been proposed to prevent and overcome the formation of the glial scar and inhibitory factors to axon regrowth. In the last decade, cell therapy has emerged as a new tool for several diseases of the nervous system. Stem cells act as minipumps providing trophic and immunomodulatory factors to enhance axonal growth, to modulate the environment, and to reduce neuroinflammation. This capability can be boosted by genetical manipulation to deliver trophic molecules. Different types of stem cells have been tested, according to their properties and the therapeutic aims. They differ from each other for origin, developmental stage, stage of differentiation, and fate lineage. Related to this, stem cells differentiating into neurons could be used for cell replacement, even though the feasibility that stem cells after transplantation in the adult lesioned spinal cord can differentiate into neurons, integrate within neural circuits, and emit axons reaching the muscle is quite remote. The timing of cell therapy has been variable, and may be summarized in the acute and chronic phases of disease, when stem cells interact with a completely different environment. Even though further experimental studies are needed to elucidate the mechanisms of action, the therapeutic, and the side effects of cell therapy, several clinical protocols have been tested or are under trial. Here, we report the state-of-the-art of cell therapy in SCI, in terms of feasibility, outcome, and side effects.

Interleukin 6 gene polymorphisms are not associated with aneurysmal subarachnoid haemorrhage in an Italian population.

OBJECTIVE: Several lines of evidence indicate a role for inflammatory processes in the development of cerebral aneurysms. Recently, polymorphisms in the promoter region of the interleukin 6 (IL6) gene were shown to be associated with intracranial aneurysmal disease. The purpose of this study was to verify the association of two functionally active polymorphisms (-174 G>C and -572 G>C) in the promoter region of the IL6 gene with the risk and clinical features of aneurysmal subarachnoid haemorrhage (SAH) in an Italian population. METHODS: A total of 179 consecutive aneurysmal SAH patients and 156 healthy controls were involved in the study. Cases and controls were genotyped for the -174 G

Antiparkinsonian therapy modifications in PD patients after STN DBS: a retrospective observational analysis.

OBJECTIVE: This study reports a retrospective analysis of 67 consecutive parkinsonian patients to assess changes in antiparkinsonian medications after Deep Brain Stimulation (DBS) of the Subthalamic Nucleus (STN). METHODS: All antiparkinsonian drugs, including levodopa, dopamine agonists, associated drugs such as COMT and MAO inhibitors, amantadine and anticholinergics, were evaluated pre- and post-operatively at 1 and 3 years follow-up. RESULTS: The levodopa mean daily dose was reduced approximately 60% after 1 year and remained stable after 3 years. Apomorphine, bromocriptine, tolcapone, entacapone and selegiline were withdrawn after STN DBS. Three years post-operatively, 9 patients (13.4%) no longer required levodopa and 6 patients (8.9%) completely stopped all dopaminergic medications. More patients were on monotherapy of either levodopa or dopamine agonist and fewer patients required a combined treatment of dopamine agonist and levodopa, compared to the pre-surgical condition. CONCLUSIONS: STN DBS treated PD patients experience a significant long-term reduction and simplification of the pharmacological treatment.

Progressive spontaneous occlusion of a cerebellar AVM: pathogenetic hypothesis and review of literature.

Cerebral arteriovenous malformation (AVM) is a complex network of vascular channels consisting of arterial feeders, a nidus and enlarged venous drainage. AVMs usually increase in size with time, but may rarely obliterate; spontaneous angiographic regression occurs in less than 1.5% of cerebral AVMs. Several causes of spontaneous regression have been postulated such us hemodynamic alterations due to hemorrhage, hypercoagulability, atherosclerosis, and tromboembolism from associated aneurysms. In this report we describe a case of spontaneous, complete and asymptomatic occlusion of a left cerebellar hemispheric AVM; angiograms clearly demonstrate a progressive decrease in size of the AVM at follow-up. Thrombosis of the dominant-draining vein caused by turbulent blood flow seemed to be the main driver. Possible mechanisms leading to the occlusion are discussed and a review of the literature is reported.

The post-surgical era of GBM: How molecular biology has impacted on our clinical management. A review.

Glioblastoma (GBM) is the most common glioma in adults, with incidence increasing by 3% per year. According to the World Health Organization Classification of Central Nervous System Tumors, GBM is considered a grade IV tumor due to its malignant behavior. The aim of this review is to summarize the main biological aspects of GBM. In particular, we focused our attention on those alterations which have been proven to have an impact on patients' outcome, mainly in terms of overall survival (OS), or on the tumor response to therapies. We have also analyzed the cellular biology and the interactions between GBM and the surrounding environment.

Apathy and verbal fluency in STN-stimulated PD patients. An observational follow-up study.

OBJECTIVE: To evaluate apathy and its relation to verbal fluency tasks in a consecutive series of 19 patients with Parkinson's disease (PD) submitted to deep brain stimulation of the subthalamic nucleus (DBS of STN). METHODS: 19 consecutive PD patients submitted to bilateral DBS of STN were studied for apathy pre-operatively and 17 months after surgery. The PD patients underwent a battery of cognitive tests assessing reasoning, memory and frontal executive functions, including phonemic and categorial fluency tasks. The Beck Depression Inventory (BDI) was used for depression. Apathy was assessed by means of the Apathy Scale (AS). In order to quantify changes among individual patients, the clinical criterion of more or less than 1 SD (standard z-score) was used to register a patient as improved or worsened, respectively. RESULTS: After surgery, apathy scores did not change and mood improved (p < 0.02), while a significant worsening was found in the phonemic fluency (p < 0.001). The percentage of patients with an apathy score above the recommended cut-off value (14) was 42% both before and after DBS of STN. Individual outcomes on the apathy scale (1 SD criterion) evidenced that 53% of the patients remained stable, 16% improved, while 31% worsened. This last percentage reduced to 21% (4/19) when considering only the PD patients with an apathy score > or =14 after surgery. No significant correlation was found between the apathy scores variation and any of the neurological variables considered, and, in particular, no correlation was found between apathy and verbal fluency. CONCLUSIONS: The results of the present study suggest that DBS of STN does not necessarily induce apathy even if individual patients show a moderate post-operative worsening of apathetic symptoms.

Motor and nonmotor symptom follow-up in parkinsonian patients after deep brain stimulation of the subthalamic nucleus.

OBJECTIVE: To evaluate motor and nonmotor symptoms in patients with Parkinson's disease undergoing bilateral deep brain stimulation of the subthalamic nucleus (STN DBS). METHODS: Thirty-six consecutive patients receiving bilateral STN stimulation implants were evaluated preoperatively as well as 12 and 24 months after surgery. Motor symptoms were assessed through the Unified Parkinson's Disease Rating Scale (UPDRS). Data concerning nonmotor symptoms were collected from items of the UPDRS and 2 additional questions from clinical charts regarding constipation and urological dysfunction. RESULTS: STN DBS was effective in controlling motor symptoms; concerning nonmotor symptoms, sleep quality and constipation improved after surgery as compared to baseline. Salivation, swallowing and sensory complaints were ameliorated to a comparable degree by the medication on state, whether preoperatively or postoperatively. With a lower dose of dopaminergic medication, however, the medication on state appeared to be a much larger percentage of the day postoperatively. No significant variations were detected in intellectual impairment, depression, thought disorders, motivation, falling unrelated to freezing, nausea, orthostatic hypotension and urological dysfunction. CONCLUSIONS: STN DBS effectively controls motor symptoms, while nonmotor features of advanced Parkinson's disease patients are mostly unchanged after surgery, even though some specific aspects, notably sleep complaints and constipation, are ameliorated.

New strategies for repairing the injured spinal cord: the role of stem cells.

Thanks to advances in the stem cell biology of the central nervous system, the previously unconceivable regeneration of the damaged spinal cord is approaching reality. A number of potential strategies aim to optimize functional recovery after spinal cord injury. They include minimizing the progression of secondary injury, manipulating the inhibitory environment of the spinal cord, replacing lost tissue with transplanted cells or peripheral nerve grafts, remyelinating denuded axons and maximizing the intrinsic regenerative potential of endogenous progenitor cells. We review the application of stem cell transplantation to the spinal cord, emphasizing the use of embryonic stem cells for remyelinating damaged axons. Recent advancements in neural injury and repair, and the progress towards development of neuroprotective and regenerative interventions are discussed.

Double concentric craniotomy: Safe and effective technique to achieve an en bloc resection of tumor involving both skull and duraa.

INTRODUCTION: Many tumors can involve the skull. Meningiomas are one of the most common intracranial neoplasms and invasion of the bone was described in 49% of cases. Other neoplastic lesions that can arise in bone, or involve it, are metastases, hemangiomas, aggressive cutis carcinomas and sarcomas. Radical excision is the golden standard of treatment but elevating a bone flap when the tumor involves both the skull and the dura could represent a technical challenge. PRESENTATION OF CASE: We report the technical details of our approach to remove a meningioma involving both skull and dura in a man aged 45. Patient underwent gross total excision and cranioplasty with PEEK custom made prothesis (Synthes™). DISCUSSION: We describe a double concentric craniotomy (DCC) technique where the tumor involving the bone is before left in situ, exposing normal dura, to perform afterwards en-bloc excision with minimal traction of brain surface. CONCLUSION: DCC is a safe and effective technique to remove tumor involving both skull and dural structures under direct vision.

Role of Nitric Oxide in Glioblastoma Therapy: Another Step to Resolve the Terrible Puzzle ?

Glioblastoma Multiforme, the most common and aggressive primary brain tumor, remains incurable despite of the advent of modern surgical and medical treatments. This poor prognosis depends by the recurrence after surgery and intrinsic or acquired resistance to chemotherapy and radiotherapy. Nitric oxide is a small molecule that plays a key roles in glioma pathophysiology. Many researches showing that NO is involved in induction of apoptosis, radiosensitization and chemosensitization. Therefore, NO role, if clarified, may improve the knowledge about this unsolved puzzle called GBM.

Alpha6 beta4 and alpha6 beta1 integrins in astrocytomas and other CNS tumors.

Laminin may alter the biological behavior of gliomas. Therefore, we investigated the expression of two laminin receptors, alpha6 beta1 and alpha6 beta4 integrins in normal brain, astrogliotic brain, and astrocytomas as compared to other central nervous system (CNS) tumors. In most CNS tumors, the expression of these integrins was unchanged in neoplastic as compared to normal counterpart cells. In contrast, increased numbers of reactive and neoplastic astrocytes expressed beta4 integrin as compared to normal astrocytes, whereas alpha6 and beta1 integrin expression did not change. Conversely, lower numbers of astrocytoma blood vessels expressed beta4, whereas all blood vessels in normal brain expressed beta4. These data suggest that the profile of laminin receptors changes in neoplastic astrocytes and in astrocytoma blood vessels; this change may play an important role in astrocytoma pathogenesis.

Neuronal and glial localization of GAT-1, a high-affinity gamma-aminobutyric acid plasma membrane transporter, in human cerebral cortex: with a note on its distribution in monkey cortex.

High-affinity gamma-aminobutyric (GABA) plasma membrane transporters (GATs) influence the action of GABA, the main inhibitory neurotransmitter in the human cerebral cortex. In this study, the cellular expression of GAT-1, the main cortical GABA transporter, was investigated in the human cerebral cortex by using immunocytochemistry with affinity-purified polyclonal antibodies directed to the C-terminus of rat GAT-1. In temporal and prefrontal association cortex (Brodmann's areas 21 and 46) and in cingulofrontal transition cortex (area 32), specific GAT-1 immunoreactivity (ir) was localized to numerous puncta and fibers in all cortical layers. GAT-1+ puncta were distributed homogeneously in all cortical layers, although they were slightly more numerous in layers II-IV, and appeared to have a preferential relationship to the somata and proximal dendrites of unlabeled pyramidal cells, even though, in many cases, they were also observed around nonpyramidal cells. Electron microscopic observations showed that GAT-1+ puncta were axon terminals that formed exclusively symmetric synapses. In addition, some distal astrocytic processes also contained immunoreaction product. Analysis of the patterns of GAT-1 labeling in temporal and prefrontal association areas (21 and 46), in cingulofrontal transition areas (32), and in somatic sensory and motor areas (1 and 4) of the monkey cortex revealed that its distribution varies according to the type of cortex examined and indicated that the distribution of GAT-1 is similar in anatomically corresponding areas of different species. The present study demonstrates that, in the human homotypical cortex, GAT-1 is expressed by both inhibitory axon terminals and astrocytic processes. This localization of GAT-1 is compatible with a major role for this transporter in GABA uptake at GABAergic synapses and suggests that GAT-1 may contribute to determining GABA levels in the extracellular space.

Properties of motor units in the first deep lumbrical muscle of the cat's foot.

Isometric contractions of single motor units were studied in the first deep lumbrical muscle of the cat's hind-foot. Motor units with short twitch contraction times (15-20 msec) generally differed from those with longer ones (23-50 msec; contraction time measured in unpotentiated twitches) in showing (1) a greater maximum tetanic tension, (2) a smaller resistance to fatigue, (3) more post-tetanic potentiation of twitch tension, and (4) no post-tetanic occurrence of repetitive activity in response to single nerve stimuli (such "post-tetanic repetitive activity" was seen in several of the slower units). The ratio between unpotentiated twitch tension and maximum tetanic tension was similar for units with brief and long contraction times. The peak-to-peak amplitude of a single motor unit spike, recorded with gross electrodes, tended to be directly proportional to the maximum tetanic tension of the same motor unit.