Cervical Spinal Cord Degeneration in Spinocerebellar Ataxia Type 7.

BACKGROUND AND PURPOSE: Spinocerebellar ataxia type 7 is an autosomal dominant neurodegenerative disease caused by a cytosine-adenine-guanine (CAG) repeat expansion. Clinically, spinocerebellar ataxia type 7 is characterized by progressive cerebellar ataxia, pyramidal signs, and macular degeneration. In vivo MR imaging studies have shown extensive gray matter degeneration in the cerebellum and, to a lesser extent, in a range of cortical cerebral areas. The purpose of this study was to evaluate the impact of the disease in the spinal cord and its relationship with the patient's impairment. MATERIALS AND METHODS: Using a semiautomated procedure applied to MR imaging data, we analyzed spinal cord area and eccentricity in a cohort of 48 patients with spinocerebellar ataxia type 7 and compared them with matched healthy controls. The motor impairment in the patient group was evaluated using the Scale for Assessment and Rating of Ataxia. RESULTS: Our analysis showed a significantly smaller cord area (t = 9.04, P < .001, d = 1.31) and greater eccentricity (t = -2.25, P =. 02, d = 0.32) in the patient group. Similarly, smaller cord area was significantly correlated with a greater Scale for Assessment and Rating of Ataxia score (r = -0.44, P = .001). A multiple regression model showed that the spinal cord area was strongly associated with longer CAG repetition expansions (P = .002) and greater disease duration (P = .020). CONCLUSIONS: Our findings indicate that cervical spinal cord changes are progressive and clinically relevant features of spinocerebellar ataxia type 7, and future investigation of these measures as candidate biomarkers is warranted.

Cannabinoid receptor CB2 ablation protects against TAU induced neurodegeneration.

Tauopathies are a group of neurodegenerative diseases characterized by the alteration/aggregation of TAU protein, for which there is still no effective treatment. Therefore, new pharmacological targets are being sought, such as elements of the endocannabinoid system (ECS). We analysed the occurrence of changes in the ECS in tauopathies and their implication in the pathogenesis. By integrating gene expression analysis, immunofluorescence, genetic and adeno-associated virus expressing TAU mouse models, we found a TAU-dependent increase in CB2 receptor expression in hippocampal neurons, that occurs as an early event in the pathology and was maintained until late stages. These changes were accompanied by alterations in the endocannabinoid metabolism. Remarkably, CB2 ablation in mice protects from neurodegeneration induced by hTAUP301L overexpression, corroborated at the level of cognitive behaviour, synaptic plasticity, and aggregates of insoluble TAU. At the level of neuroinflammation, the absence of CB2 did not produce significant changes in concordance with a possible neuronal location rather than its classic glial expression in these models. These findings were corroborated in post-mortem samples of patients with Alzheimer's disease, the most common tauopathy. Our results show that neurons with accumulated TAU induce the expression of the CB2 receptor, which enhances neurodegeneration. These results are important for our understanding of disease mechanisms, providing a novel therapeutic strategy to be investigated in tauopathies.

Identification of putative miRNA biomarkers in early rheumatoid arthritis by genome-wide microarray profiling: A pilot study.

Despite the existing research, the etiology of rheumatoid arthritis (RA), an autoimmune disease remains poorly understood with early and accurate diagnosis difficult to achieve. MicroRNAs (miRNAs) play an important role in biological processes as modulators of transcription and translation. Previous studies have demonstrated a downregulation of several genes in early RA stages and in addition, miRNAs may serve as early biomarkers of subclinical changes in early RA. When comparing the four groups (ANOVA P < 0.01, fold change > 4), we found 253 differentially expressed miRNAs. Of these, 97 miRNAs were identified as overexpressed in early rheumatoid arthritis. The validation of miRNA microarray expression was performed in a set by RT-qPCR and showed strong agreement with microarray expression data. The putative targets of overexpressed microRNAs in early RA were significantly enriched in apoptosis, tolerance loss and Wnt pathways. Moreover, ROC analysis showed values of AUC 0.76 and P < 0.05 for miR 361-5p, identifying this miRNA as a potential biomarker of disease. We identified specific microRNAs associated with early rheumatoid arthritis and proposed them as early biomarkers of disease. Our results provide novel insight into immune disease physiopathology and describe unreported microRNAs in RA with potential for clinical use.

Ophthalmic features of spinocerebellar ataxia type 7.

PurposeTo analyze the relation between ophthalmologic and motor changes in spinocerebellar ataxia type 7 (SCA7).Patients and methodsThis was a case series study. Sixteen SCA7 patients underwent a comprehensive ophthalmic examination, including ocular extrinsic motility testing, color vision test, and optical coherence tomography of the optic nerve and macula. Changes in the corneal endothelium, electroretinographic patterns, and a complete neurologic evaluation using the Scale for the Assessment and Rating of Ataxia (SARA) were evaluated. Correlations of endothelial cell density (ECD) with number of CAG repetitions and the SARA scores were estimated.ResultsAll patients showed various degrees of visual impairment mainly due to macular deterioration. Notably, they also presented decreased ECD. Pairwise correlations of ECD with number of CAG repeats and severity of motor symptoms quantified with the SARA scores were inverse (r=-0.46, P=0.083 and r=-0.64, P=0.009, respectively). Further analyses indicated an average ECD decrease of 48 cells/mm2 (P=0.006) per unit of change on the number of CAG repeats, and of 75 cells/mm2 (P=0.001) per unit of change on the SARA scores.ConclusionsThe results agree with previous ophthalmological findings regarding the widespread effect of SCA7 mutation on the patient's visual system. However, the results also show a significant negative correlation of decreased ECD with both CAG repetitions and SARA scores. This suggests that motor systems could degenerate in parallel with visual systems, although more research is needed to determine whether the degeneration is caused by the same mechanisms.

Ataxia Severity Correlates with White Matter Degeneration in Spinocerebellar Ataxia Type 7.

BACKGROUND AND PURPOSE: There is a scarcity of information on the effect of white matter degeneration in patients with spinocerebellar ataxia type 7. Therefore, we investigated the WM integrity in a large group of patients with spinocerebellar ataxia type 7 by using Tract-Based Spatial Statistics. MATERIALS AND METHODS: Thirty-three patients with a molecular diagnosis of spinocerebellar ataxia type 7 and their age- and sex-matched healthy controls participated in this study. The patients' ataxia severity was evaluated with the Scale for the Assessment and Rating of Ataxia. Voxelwise analyses of diffusion metrics, including fractional anisotropy and mean diffusivity, were performed with Tract-Based Spatial Statistics. The correlation between WM abnormalities and ataxia severity was then calculated. RESULTS: Tract-Based Spatial Statistics analysis revealed WM abnormalities in the cerebellum and the cerebellar peduncles, as well as in other major cortical and subcortical pathways. Further analysis between the Scale for the Assessment and Rating of Ataxia score and WM mean diffusivity showed significant associations only in key areas related to motor control and visuospatial processing, including the cerebellar WM, the middle occipital WM, the superior cerebellar peduncle, and bilateral anterior thalamic radiation. No significant associations between fractional anisotropy and the Scale for the Assessment and Rating of Ataxia were found. CONCLUSIONS: These results suggest a significant contribution of local cerebellar and cerebellar-midbrain connections to ataxic impairment in spinocerebellar ataxia type 7. The results also suggest an involvement of cortical WM abnormalities including tracts within the occipital and frontal cortices. These findings contribute to a more comprehensive view of the clinical impact of the white matter degeneration in spinocerebellar ataxia type 7.

Tractography at 3T MRI of Corpus Callosum Tracts Crossing White Matter Hyperintensities.

BACKGROUND AND PURPOSE: The impact of white matter hyperintensities on the diffusion characteristics of crossing tracts is unclear. This study used quantitative tractography at 3T MR imaging to compare, in the same individuals, the diffusion characteristics of corpus callosum tracts that crossed white matter hyperintensities with the diffusion characteristics of corpus callosum tracts that did not pass through white matter hyperintensities. MATERIALS AND METHODS: Brain T2 fluid-attenuated inversion recovery-weighted and diffusion tensor 3T MR imaging scans were acquired in 24 individuals with white matter hyperintensities. Tractography data were generated by the Fiber Assignment by Continuous Tracking method. White matter hyperintensities and corpus callosum tracts were manually segmented. In the corpus callosum, the fractional anisotropy, radial diffusivity, and mean diffusivity of tracts crossing white matter hyperintensities were compared with the fractional anisotropy, radial diffusivity, and mean diffusivity of tracts that did not cross white matter hyperintensities. The cingulum, long association fibers, corticospinal/bulbar tracts, and thalamic projection fibers were included for comparison. RESULTS: Within the corpus callosum, tracts that crossed white matter hyperintensities had decreased fractional anisotropy compared with tracts that did not pass through white matter hyperintensities (P = .002). Within the cingulum, tracts that crossed white matter hyperintensities had increased radial diffusivity compared with tracts that did not pass through white matter hyperintensities (P = .001). CONCLUSIONS: In the corpus callosum and cingulum, tracts had worse diffusion characteristics when they crossed white matter hyperintensities. These results support a role for white matter hyperintensities in the disruption of crossing tracts.

[Satisfaction of principal caregivers of patients followed-up by palliative care teams]. / Grado de satisfacción de los cuidadores principales de pacientes seguidos por los equipos de cuidados paliativos.

OBJECTIVE: To determine the satisfaction of main caregivers of deceased patients followed-up by palliative care teams. METHOD: Web research on electronic data bases: PubMed and MEDES, using "Palliative Care" and "Patient Satisfaction" as main descriptors, and "Family", "Professional-Family Relations", "Quality of Health Care" and "Quality Assurance, Health Care" as secondary descriptors. Studies written in Spanish and English were included. RESULTS: Profile of principal caregiver: a woman between her mid-forties and her mid-fifties, usually related with the patient as a daughter, and of primary educational level. The items that the main caregivers valued the most were: a kind manner, feeling free to ask questions about problems during the process, tactful explanations, receiving information, pain management, time for answering questions, interest for emotional problems, and information about treatment. The worse valued items were: symptoms control, lack of psychological support after death, preparation for a death of a relative, keeping in touch after death, help to resolve outstanding issues, and help during grief. In general, a great majority of palliative care teams achieved excellent results. CONCLUSION: In spite of the good results obtained in satisfaction surveys from caregivers with regard to palliative care teams, it is essential to improve the quality of scientific-technical training (both from the medical and the psychological point of view), as well as to improve communicational skills among palliative care staff.

Biological characterization of PM226, a chromenoisoxazole, as a selective CB2 receptor agonist with neuroprotective profile.

Cannabinoids have emerged as promising neuroprotective agents due to their capability to activate specific targets, which are involved in the control of neuronal homeostasis and survival. Specifically, those ligands that selectively target and activate the CB2 receptor may be useful for their anti-inflammatory and neuroprotective properties in various neurological disorders, with the advantage of being devoid of psychotropic effects associated with the activation of CB1 receptors. The aim of this work has been to investigate the neuroprotective properties of 7-(1,1-dimethylheptyl)-4,4-dimethyl-9-methoxychromeno[3,4-d]isoxazole (PM226), a compound derived from a series of chromeno-isoxazoles and -pyrazoles, which seems to have a promising profile related to the CB2 receptor. The compound binds selectively to this receptor with an affinity in the nanomolar range (Ki=12.8±2.4nM). It has negligible affinity for the CB1 receptor (Ki>40000nM) and no activity at the GPR55. PM226 was also evaluated in GTPγS binding assays specific to the CB2 receptor showing agonist activity (EC50=38.67±6.70nM). In silico analysis of PM226 indicated that it has a good pharmacokinetic profile and a predicted ability to cross the blood-brain barrier. Next, PM226 was investigated in an in vitro model to explore its anti-inflammatory/neuroprotective properties. Conditioned media were collected from LPS-stimulated cultures of BV2 microglial cell line in the absence or presence of different doses of PM226, and then media were added to cultured M213-2O neuronal cells to record their influence on cell viability evaluated using MTT assays. As expected, cell viability was significantly reduced by the exposure to these conditioned media, while the addition of PM226 attenuated this reduction in a dose-dependent manner. This effect was reversed by co-incubating with the CB2 antagonist SR144528, thus confirming the involvement of CB2 receptors, whereas the addition of PM226 to neuronal cultures instead cultured BV2 cells was not effective. PM226 has also been studied in an in vivo model of mitochondrial damage generated by intrastriatal application of malonate in rats. MRI analysis showed that PM226 administration decreased the volume of the striatal lesion caused by malonate, effect that was confirmed after the histopathological evaluation (Nissl staining, Iba-1 immunostaining and TUNEL assay) of striatal sections derived from malonate-lesioned rats in the absence or presence of PM226. Again, the beneficial effects of PM226 were dependent on the activation of CB2 receptors as they were reversed by blocking these receptors with AM630. Overall, PM226 has shown to have a promising neuroprotective profile derived from its ability to selectively activate CB2 receptor, so that it could be a useful disease-modifying agent in those neurodegenerative pathologies in which the activation of these receptors may have therapeutic value.

A Sativex(®) -like combination of phytocannabinoids as a disease-modifying therapy in a viral model of multiple sclerosis.

BACKGROUND AND PURPOSE: Sativex(®) is an oromucosal spray, containing equivalent amounts of Δ(9) -tetrahydrocannabinol (Δ(9) -THC) and cannabidiol (CBD)-botanical drug substance (BDS), which has been approved for the treatment of spasticity and pain associated to multiple sclerosis (MS). In this study, we investigated whether Sativex may also serve as a disease-modifying agent in the Theiler's murine encephalomyelitis virus-induced demyelinating disease model of MS. EXPERIMENTAL APPROACH: A Sativex-like combination of phytocannabinoids and each phytocannabinoid alone were administered to mice once they had established MS-like symptoms. Motor activity and the putative targets of these cannabinoids were assessed to evaluate therapeutic efficacy. The accumulation of chondroitin sulfate proteoglycans (CSPGs) and astrogliosis were assessed in the spinal cord and the effect of Sativex on CSPGs production was evaluated in astrocyte cultures. KEY RESULTS: Sativex improved motor activity - reduced CNS infiltrates, microglial activity, axonal damage - and restored myelin morphology. Similarly, we found weaker vascular cell adhesion molecule-1 staining and IL-1ß gene expression but an up-regulation of arginase-1. The astrogliosis and accumulation of CSPGs in the spinal cord in vehicle-infected animals were decreased by Sativex, as was the synthesis and release of CSPGs by astrocytes in culture. We found that CBD-BDS alone alleviated motor deterioration to a similar extent as Sativex, acting through PPARγ receptors whereas Δ(9) -THC-BDS produced weaker effects, acting through CB2 and primarily CB1 receptors. CONCLUSIONS AND IMPLICATIONS: The data support the therapeutic potential of Sativex to slow MS progression and its relevance in CNS repair.

The inhibition of 2-arachidonoyl-glycerol (2-AG) biosynthesis, rather than enhancing striatal damage, protects striatal neurons from malonate-induced death: a potential role of cyclooxygenase-2-dependent metabolism of 2-AG.

The cannabinoid CB2 receptor, which is activated by the endocannabinoid 2-arachidonoyl-glycerol (2-AG), protects striatal neurons from apoptotic death caused by the local administration of malonate, a rat model of Huntington's disease (HD). In the present study, we investigated whether endocannabinoids provide tonic neuroprotection in this HD model, by examining the effect of O-3841, an inhibitor of diacylglycerol lipases, the enzymes that catalyse 2-AG biosynthesis, and JZL184 or OMDM169, two inhibitors of 2-AG inactivation by monoacylglycerol lipase (MAGL). The inhibitors were injected in rats with the striatum lesioned with malonate, and several biochemical and morphological parameters were measured in this brain area. Similar experiments were also conducted in vitro in cultured M-213 cells, which have the phenotypic characteristics of striatal neurons. O-3841 produced a significant reduction in the striatal levels of 2-AG in animals lesioned with malonate. However, surprisingly, the inhibitor attenuated malonate-induced GABA and BDNF deficiencies and the reduction in Nissl staining, as well as the increase in GFAP immunostaining. In contrast, JZL184 exacerbated malonate-induced striatal damage. Cyclooxygenase-2 (COX-2) was induced in the striatum 24 h after the lesion simultaneously with other pro-inflammatory responses. The COX-2-derived 2-AG metabolite, prostaglandin E2 glyceryl ester (PGE2-G), exacerbated neurotoxicity, and this effect was antagonized by the blockade of PGE2-G action with AGN220675. In M-213 cells exposed to malonate, in which COX-2 was also upregulated, JZL184 worsened neurotoxicity, and this effect was attenuated by the COX-2 inhibitor celecoxib or AGN220675. OMDM169 also worsened neurotoxicity and produced measurable levels of PGE2-G. In conclusion, the inhibition of 2-AG biosynthesis is neuroprotective in rats lesioned with malonate, possibly through the counteraction of the formation of pro-neuroinflammatory PGE2-G, formed from COX-2-mediated oxygenation of 2-AG. Accordingly, MAGL inhibition or the administration of PGE2-G aggravates the malonate toxicity.

Control of experimental spasticity by targeting the degradation of endocannabinoids using selective fatty acid amide hydrolase inhibitors.

BACKGROUND: It has been previously shown that CB1 cannabinoid receptor agonism using cannabis extracts alleviates spasticity in both a mouse experimental autoimmune encephalomyelitis (EAE) model and multiple sclerosis (MS) in humans. However, this action can be associated with dose-limiting side effects. OBJECTIVE: We hypothesised that blockade of anandamide (endocannabinoid) degradation would inhibit spasticity, whilst avoiding overt cannabimimetic effects. METHODS: Spasticity eventually developed following the induction of EAE in either wild-type or congenic fatty acid amide hydrolase (FAAH)-deficient Biozzi ABH mice. These animals were treated with a variety of different FAAH inhibitors and the effect on the degree of limb stiffness was assessed using a strain gauge. RESULTS: Control of spasticity was achieved using FAAH inhibitors CAY100400, CAY100402 and URB597, which was sustained following repeated administrations. Therapeutic activity occurred in the absence of overt cannabimimetic effects. Importantly, the therapeutic value of the target could be definitively validated as the treatment activity was lost in FAAH-deficient mice. Spasticity was also controlled by a selective monoacyl glycerol lipase inhibitor, JZL184. CONCLUSIONS: This study demonstrates definitively that FAAH inhibitors provide a new class of anti-spastic agents that may have utility in treating spasticity in MS and avoid the dose-limiting side effects associated with cannabis use.

Neuroprotective Properties of Standardized Extracts of Hypericum perforatum on Rotenone Model of Parkinson's Disease.

Hipericum perforatum is a well-known herbal for its antidepressant property. Recently, it has been shown to have nootropic effects against neurodegenerative disorders. The aim of the present study was to evaluate the protective role of chronic administration of two standardized extract of Hypericum perforatum SHP1 rich in hyperforin (6%) and SHP2 extract poor in hyperforin (0.2%) on the neurodegeneration induced by chronic administration of rotenone in rats. Quercetin in liposomes, one active constituent, was tested in the same experimental conditions. The animals received pretreatments with SHP1 (4 mg/Kg, ip), SHP2 (4 mg/Kg, ip) or quercetin liposomes (25 and 100 mg/kg, ip) 60 min before of rotenone injection (2.5 mg/kg) for 45 days. Pretreatment of the animals with SHP1 and SHP2 efficiently halted deleterious toxic effects of rotenone, revealing normalization of catalepsy in addition to amelioration of neurochemical parameters. Also, SHP1 reduced neuronal damage, diminishing substantia nigra dopaminergic cell death caused by the pesticide, indicating benefit of neuroprotective therapy. In general, the SHP1 was more active than SHP2. In addition, SHP1 inhibited the apoptotic cascade by decreasing Bax levels. The results presented here indicate that mainly hyperforin and quercetin, may be involved in the neuroprotective action of Hypericum standardized extracts. Combination of dietary antioxidants could provide better therapeutic advantage for the management of Parkinson, and possibly other neurodegenerative disorders. Therefore H. perforatum standardized extract enriched in hyperforin, could be a better alternative for depressed elderly patients with degenerative disorders exhibiting elevated oxidative stress status.

Inhibition of endoplasmic reticulum Ca²âº ATPase in preBötzinger complex of neonatal rat does not affect respiratory rhythm generation.

PreBötzinger complex (preBötC) neurons in the brainstem underlie respiratory rhythm generation in vitro. As a result of network interactions, preBötC neurons burst synchronously to produce rhythmic premotor inspiratory activity. Each inspiratory neuron has a characteristic 10-20 mV, 0.3-0.8 s synchronous depolarization known as the inspiratory drive potential or inspiratory envelope, topped by action potentials (APs). Mechanisms involving Ca(2+) fluxes have been proposed to underlie the initiation of the inspiratory drive potential. An important source of intracellular Ca(2+) is the endoplasmic reticulum (ER) in which active Ca(2+) sequestration is mediated by a class of transporters termed sarco/endoplasmic reticulum Ca(2+) ATPases (SERCAs). We aim to test the hypothesis that disruption of Ca(2+) sequestration into the ER affects respiratory rhythm generation. We examined the effect of inhibiting SERCA on respiratory rhythm generation in an in vitro slice preparation. Bath application of the potent SERCA inhibitors thapsigargin or cyclopiazonic acid (CPA) for up to 90 min did not significantly affect the period or amplitude of respiratory-related motor output or integral and duration of inspiratory drive in preBötC neurons. We promoted the depletion of intracellular Ca(2+) stores by a transient bath application of 30 mM K(+) (high K(+)) in the continuous presence of thapsigargin or CPA. After washing out the high K(+), respiratory rhythm period and amplitude returned to baseline values. These results show that after inhibition of SERCA and depletion of intracellular Ca(2+) stores, respiratory rhythm remains substantially the same, suggesting that this source of Ca(2+) does not significantly contribute to rhythm generation in the preBötC in vitro.

Cannabidiol administration after hypoxia-ischemia to newborn rats reduces long-term brain injury and restores neurobehavioral function.

Cannabidiol (CBD) demonstrated short-term neuroprotective effects in the immature brain following hypoxia-ischemia (HI). We examined whether CBD neuroprotection is sustained over a prolonged period. Newborn Wistar rats underwent HI injury (10% oxygen for 120 min after left carotid artery electrocoagulation) and then received vehicle (HV, n = 22) or 1 mg/kg CBD (HC, n = 23). Sham animals were similarly treated (SV, n = 16 and SC, n = 16). The extent of brain damage was determined by magnetic resonance imaging, histological evaluation (neuropathological score, 0-5), magnetic resonance spectroscopy and Western blotting. Several neurobehavioral tests (RotaRod, cylinder rear test[CRT],and novel object recognition[NOR]) were carried out 30 days after HI (P37). CBD modulated brain excitotoxicity, oxidative stress and inflammation seven days after HI. We observed that HI led to long-lasting functional impairment, as observed in all neurobehavioral tests at P37, whereas the results of HC animals were similar to those of sham animals (all p < 0.05 vs. HV). CBD reduced brain infarct volume by 17% (p < 0.05) and lessened the extent of histological damage. No differences were observed between the SV and SC groups in any of the experiments. In conclusion, CBD administration after HI injury to newborn rats led to long-lasting neuroprotection, with the overall effect of promoting greater functional rather than histological recovery. These effects of CBD were not associated with any side effects. These results emphasize the interest in CBD as a neuroprotective agent for neonatal HI.

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