Archives Italiennes De Biologie最新文献

Imitation is a human ability rooted in early life. It allows people to interact with each other by observing and reproducing simple and complex movements alike. Imitation can occur in at least two forms: the rst, de ned as anatomical, seems to be based primarily on the mental construct of the "body schema" because the imitating movement corresponds precisely to the imitated movement in bodily terms, but not in terms of spatial compatibility. For example, a right arm movement of a model is imitated with a right arm movement by a facing imitator in a spatially incompatible fashion. The other form, de ned as specular or mirror-mode, involves a spatially compatible matching between imitated and imitating movements, as when an imitator moves her right arm upon viewing a corresponding left arm movement of a facing model (Chiavarino et al., 2007). In a previous study, healthy subjects showed a slight (61%) preference for the specular mode when freely imitating meaningful and meaningless gestures, whereas they strongly preferred the anatomical mode (93%) when given an intentionally ambiguous instruction such as "use the same (or the opposite) limb as the model" (Pierpaoli et al., 2014). In the present investigation it has been shown that callosotomized patients tended to favour the mirror-mode in both the free (66%) and the instructed condition (61% responses in driven sessions) regardless instructions given by the experimenter. Moreover, present data suggest that the extent of the callosotomy may in uence the patient's performance.

Deficits in social-cognition processing have been identified during early stages of Huntington Disease (HD), attracting interest on their relevance as possible predictors of  neurodegenerative progression. Since the neurotrophin Brain-Derived Neurotrophic Factor (BDNF) and the serotonin (5-HT) transporter (SERT) are known to modulate human adaptive behavior, we appraised these two proteins in mild-HD using blood platelets, with the aim at finding relationships with cognitive/psychosocial skills. Thirteen gene positive and symptomatic patients (9M/4W, HD-stage II, age> 40y) together 11 gender/age matched controls without a concurrent diagnosis of psychiatric disorders, underwent a blood test to determine BDNF storage and membrane-bound SERT in platelets by an ELISA immune-enzyme dosage and [3H]-paroxetine ([3H]-PAR) binding, respectively. Enrolled subjects were concurrently evaluated through a battery of socio-cognitive tests and emotion recognition questionnaires.Results showed greater intra-platelet BDNF (~ +20-22%) in patients versus controls, whereas equilibrium [3H]-PAR binding parameters, maximum density (Bmax) and dissociation constant (KD), did not appreciably vary in the two comparison groups. Cognitive/emotion abilities were found significantly reduced in patients. Additionally, platelet BDNF was unrelated to psycho-cognitive scores, but positively correlated with the illness duration. As well, SERT Bmax was unconnected to HD signs or socio-cognitive scores, whilst KDs negatively correlated with scores for angry voice recognition in both controls and patients. This pilot study suggests that platelet BDNF and SERT do not specifically underlie psychosocial deficits in stage II-HD, while higher BDNF storage in delayed mild symptoms, would derive from compensatory mechanisms. Supplementary investigations are warranted, by also comparing patients in other illness's phases.

No abstract available.

Alzheimer's disease (AD) is a chronic degenerative disease characterized by the presence of amyloid plaques and neurofibrillary tangles (NFTs), which results into memory and learning impairments. In the present study, we showed that the aggregates formed by a protein that has no link with Alzheimer's disease, namely the hen egg white lysozyme (HEWL), were cytotoxic and decreased spatial learning and memory in rats. The effect of Ag-nano particles (Ag-NPs) was investigated on disruption of amyloid aggregation and preservation of cognitive behavior of rats. Twenty-four male Wistar rats were divided into 4 groups including a control group, and injected with either scopolamine, lysozyme or aggregates pre-incubated with Ag-NPs. Rats' behavior was monitored using Morris water maze (MWM) twenty days after injections. HEWL aggregation in the presence and absence of the Ag-NPs was assayed by Thioflavin T binding, atomic force microscopy and cell-based cytotoxicity assay. Ag-NPs were capable to directly disrupt HEWL oligomerization and the resulting aggregates were non-toxic. We also showed that rats of the Ag-NPs group found MWM test platform in less time and with less distance traveled, in comparison with lysozyme group. Ag-NPs also increased the percentage of time elapsed and the distance swum in the target quadrant in the rat model of AD, in probe test. These observations suggest that Ag-NPs improved spatial learning and memory by inhibiting amyloid fibril-induced neurotoxicity. Furthermore, we suggest using model proteins as a valid tool to investigate the pathogenesis of Alzheimer's disease.

Amyotrophic lateral sclerosis (ALS) is traditionally considered a disease affecting exclusively motor neurons. However, much evidence points towards additional involvement of brain systems other than the motor. As much as half of ALS patients display cognitive-behavioral disturbances. ALS shares with a considerable proportion of FTD cases the same neuropathological substrate, namely, inclusions of abnormally phosphorylated protein TDP-43 (pTDP-43). In analogy with pathological staging systems elaborated in the past decades for Alzheimer's disease (AD) and Parkinson's disease (PD), a model of staging of pTDP-43 pathology in sporadic ALS (sALS) has been recently proposed. According to it, 4 stages can be recognized, where pTDP-43 inclusions are found in the agranular motor cortex and α-motor neurons of the brain stem and spinal cord (stage 1), in prefrontal neocortex (middle frontal gyrus), reticular formation, and precerebellar nuclei (stage 2), in further areas of the prefrontal neocortex (gyrus rectus and orbitofrontal gyri), postcentrally located sensory cortex, and basal ganglia (stage 3), and in the anteromedial temporal lobe including the hippocampus (stage 4). Based on this staging effort, a corticofugal axonal model for spreading of pathology can be hypothesized, whereby pathology starts in the primary motor cortex and spreads from there via axonal projections to lower motor neurons and to subcortical structures. Recent neuroradiological evidence seems to support the proposed staging system. From the clinical standpoint, a proportion of ALS patients display extramotor deficits (namely cognitive-behavioural disturbances, impaired ocular movements, and extrapyramidal alterations), which seem to correspond to the pathological involvement of the relevant cerebral structures. This review describes neuropathological sALS staging and addresses clinical evidence corresponding to this staging, pointing towards the concept of ALS as a multisystem brain degeneration disorder instead of a disease confined to motor neurons.

Neural progenitor cells (NPC) represent the stem-like niche of the central nervous system that maintains a regenerative potential also in the adult life. Despite NPC in the brain are well documented, the presence of NPC in the spinal cord has been controversial for a long time. This is due to a scarce activity of NPC within spinal cord, which also makes difficult their identification. The present review recapitulates the main experimental studies, which provided evidence for the occurrence of NPC within spinal cord, with a special emphasis on spinal cord injury and amyotrophic lateral sclerosis. By using experimental models, here we analyse the site-specificity, the phenotype and the main triggers of spinal cord NPC. Moreover, data are reported on the effect of specific neurogenic stimuli on these spinal cord NPC in an effort to comprehend the endogenous neurogenic potential of this stem cell niche.

The mechanisms underlying motoneuron degeneration in amyotrophic lateral sclerosis (ALS), a neurodegenerative disorder that affects the motor system with progressive paralysis, are complex and not yet fully understood. It is generally agreed that ALS is a multifactorial and multisystem disease due not only possibly to genetic causes but also to other factors like oxidative stress, mitochondrial dysfunction, protein aggregation, RNA dysmetabolism, autophagy, and excitotoxicity glutamate-mediate. Altered oxidative stress biomarker profile has been repeatedly reported in ALS patients, which may suggest that abnormal free radical production is relevant in the ALS pathogenesis. This review aims to investigate how oxidative stress can affect other proposed mechanisms of neurodegeneration in ALS.

Amyotrophic lateral sclerosis (ALS) is traditionally considered a disease affecting exclusively motor neurons: compelling evidence points now towards additional involvement of extramotor functions. Beside the cognitive-behavioural disturbances, many ALS patients express extrapyramidal deficits: neuropathological findings fully support the multisystem brain degeneration. The therapeutical option to treat the multisystemic character of ALS represents an additional difficult task in absence of sensitive biomarkers or better understanding of the pathophysiological mechanisms of the disease. Future clinical trials need to identify subgroups of patients, representing the post-hoc analysis after a trial the extreme effort to define sensitive ALS patients to new treatments, as the edaravone story seems to demonstrate.

Amyotrophic Lateral Sclerosis (ALS) is a progressive neurodegenerative disease characterized by degeneration of both upper and lower motor neuron located in the spinal cord and brainstem. Diagnosis of ALS is predominantly clinical, nevertheless, electromyography and Magnetic Resonance Imaging (MRI) may provide support. Several advanced MRI techniques have been proven useful for ALS diagnosis and, indeed, the combination of different MRI techniques demonstrated an improvement in sensitivity and specificity as far as 90%. This review focus on the imaging techniques currently used in the diagnosis and management of ALS with brief considerations on future applications.

Amyotrophic lateral sclerosis (ALS) is fatal neurodegenerative disease clinically characterized by upper and lower motor neuron dysfunction resulting in rapidly progressive paralysis and death from respiratory failure. Most cases appear to be sporadic, but 5-10 % of cases have a family history of the disease, and over the last decade, identification of mutations in about 20 genes predisposing to these disorders has provided the means to better understand their pathogenesis. Next Generation sequencing (NGS) is an advanced high-throughput DNA sequencing technology which have rapidly contributed to an acceleration in the discovery of genetic risk factors for both familial and sporadic neurological and neurodegenerative diseases. These strategies allowed to rapidly identify disease-associated variants and genetic risk factors for both familial (fALS) and sporadic ALS (sALS), strongly contributing to the knowledge of the genetic architecture of ALS. Moreover, as the number of ALS genes grows, many of the proteins they encode are in intracellular processes shared with other known diseases, suggesting an overlapping of clinical and phatological features between different diseases. To emphasize this concept, the review focuses on genes coding for Valosin-containing protein (VPC) and two Heterogeneous nuclear RNA-binding proteins (HNRNPA1 and hnRNPA2B1), recently idefied through NGS, where different mutations have been associated in both ALS and other neurological and neurodegenerative diseases.