European Brain Research Institute EBRI

Rome, Italy

European Brain Research Institute EBRI

Rome, Italy
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Latina V.,National Research Council Italy | Caioli S.,IRCCS Santa Lucia Foundation | Zona C.,IRCCS Santa Lucia Foundation | Zona C.,University of Rome Tor Vergata | And 4 more authors.
Frontiers in Cellular Neuroscience | Year: 2017

Alterations in NGF/TrkA signaling have been suggested to underlie the selective degeneration of the cholinergic basal forebrain neurons occurring in vivo in AD (Counts and Mufson, 2005; Mufson et al., 2008; Niewiadomska et al., 2011) and significant reduction of cognitive decline along with an improvement of cholinergic hypofunction have been found in phase I clinical trial in humans affected from mild AD following therapeutic NGF gene therapy (Tuszynski et al., 2005, 2015). Here, we show that the chronic (10–12 D.I.V.) in vitro treatment with NGF (100ng/ml) under conditions of low supplementation (0.2%) with the culturing serum-substitute B27 selectively enriches the basal forebrain cholinergic neurons (+36.36%) at the expense of other non-cholinergic, mainly GABAergic (−38.45%) and glutamatergic (−56.25%), populations. By taking advantage of this newly-developed septo-hippocampal neuronal cultures, our biochemical and electrophysiological investigations demonstrate that the early failure in excitatory neurotransmission following NGF withdrawal is paralleled by concomitant and progressive loss in selected presynaptic and vesicles trafficking proteins including synapsin I, SNAP-25 and α-synuclein. This rapid presynaptic dysfunction: (i) precedes the commitment to cell death and is reversible in a time-dependent manner, being suppressed by de novo external administration of NGF within 6 hr from its initial withdrawal; (ii) is specific because it is not accompanied by contextual changes in expression levels of non-synaptic proteins fromother subcellular compartments; (ii) is not secondary to axonal degeneration because it is insensible to pharmacological treatment with known microtubule-stabilizing drug such paclitaxel; (iv) involves TrkA-dependent mechanisms because the effects of NGF reapplication are blocked by acute exposure to specific and cell-permeable inhibitor of its high-affinity receptor. Taken together, this study may have important clinical implications in the field of AD neurodegeneration because it: (i) provides new insights on the earliest molecular mechanisms underlying the loss of synaptic/trafficking proteins and, then, of synapes integrity which occurs in vulnerable basal forebrain population at preclinical stages of neuropathology; (ii) offers prime presynaptic-based molecular target to extend the therapeutic time-windowof NGF action in the strategy of improving its neuroprotective in vivo intervention in affected patients. © 2017 Latina, Caioli, Zona, Ciotti, Amadoro and Calissano.


Borreca A.,National Research Council Italy | Gironi K.,University of Rome La Sapienza | Amadoro G.,National Research Council Italy | Amadoro G.,European Brain Research Institute EBRI | Ammassari-Teule M.,National Research Council Italy
Molecular Neurobiology | Year: 2016

Amyloid precursor protein (APP) is overexpressed in familiar and sporadic Alzheimer Disease (AD) patients suggesting that, in addition to abnormalities in APP cleavage, enhanced levels of APP full length might contribute to the pathology. Based on data showing that the two RNA binding proteins (RBPs), Fragile-X Mental Retardation Protein (FMRP) and heteronuclear Ribonucleoprotein C (hnRNP C), exert an opposite control on APP translation, we have analyzed whether expression and translation of these two RBPs vary in relation to changes in APP protein and mRNA levels in the AD brain at 1, 3, and 6 months of age. Here, we show that, as expected, human APP is overexpressed in hippocampal total extract from Tg2576 mice at all age points. APP overexpression, however, is not stable over time but reaches its maximal level in 1-month-old mutants in association with the stronger (i) reduction of FMRP and (ii) augmentation of hnRNP C. APP levels then decrease progressively as a function of age in close relationship with the gradual normalization of FMRP and hnRNP C levels. Consistent with the mouse data, expression of FMRP and hnRNP C are, respectively, decreased and increased in hippocampal synaptosomes from sporadic AD patients. Our findings identify two RBP targets that might be manipulated for reducing abnormally elevated levels of APP in the AD brain, with the hypothesis that acting upstream of amyloidogenic processing might contribute to attenuate the amyloid burden. © 2015, Springer Science+Business Media New York.


Bobba A.,CNR Institute of Biomembrane and Bioenergetics | Amadoro G.,CNR Institute of Neuroscience | Valenti D.,CNR Institute of Biomembrane and Bioenergetics | Corsetti V.,European Brain Research Institute EBRI | And 2 more authors.
Mitochondrion | Year: 2013

Here we investigate the effect of β-amyloid on mitochondrial respiratory function, i.e.mitochondrial oxygen consumption and membrane potential generation as well as the individual activities of both the mitochondrial Complexes I-IV, that compose mitochondrial electron transport chain, and the ATP synthase, by using homogenate from cerebellar granule cells, treated with low concentrations of β-amyloid, and Alzheimer synaptic-enriched brain samples. We found that β-amyloid caused both a selective defect in Complex I activity associated with an increase (5 fold) of intracellular reactive oxygen species and an impairment of Complex IV likely due to membrane lipid peroxidation. In addition, a 130% increase of the GSSG/GSH ratio was measured in Alzheimer brains with respect to age-matched controls. Knowing the mechanisms of action of β-amyloid could allow to mitigate or even to interrupt the toxic cascade that leads a cell to death. The results of this study represent an important innovation because they offer the possibility to act at mitochondrial level and on specific sites to protect cells, for example by preventing the interaction of β-amyloid with the identified targets, by stabilizing or by restoring mitochondrial function or by interfering with the energy metabolism. © 2013 Elsevier B.V. and Mitochondria Research Society.


Bobba A.,CNR Institute of Neuroscience | Amadoro G.,CNR Institute of Neuroscience | La Piana G.,University of Bari | Calissano P.,European Brain Research Institute EBRI | Atlante A.,CNR Institute of Neuroscience
Apoptosis | Year: 2015

Alzheimer's disease (AD) and cancer proceed via one or more common molecular mechanisms: a metabolic shift from oxidative phosphorylation to glycolysis - corresponding to the activation of the Warburg effect - occurs in both diseases. The findings reported in this paper demonstrate that, in the early phase of apoptosis, glucose metabolism is enhanced, i.e. key proteins which internalize and metabolize glucose - glucose transporter, hexokinase and phosphofructokinase - are up-regulated, in concomitance with a parallel decrease in oxygen consumption by mitochondria and increase of l-lactate accumulation. Reversal of the glycolytic phenotype occurs in the presence of dichloroacetate, inhibitor of the pyruvate dehydrogenase kinase enzyme, which speeds up apoptosis of cerebellar granule cells, reawakening mitochondria and then modulating glycolytic enzymes. Loss of the adaptive advantage afforded by aerobic glycolysis, which occurs in the late phase of apoptosis, exacerbates the pathological processes underlying neurodegeneration, leading inevitably the cell to death. In conclusion, the data propose that both aerobic, i.e. Warburg effect, essentially due to the protective numbness of mitochondria, and anaerobic glycolysis, rather due to the mitochondrial impairment, characterize the entire time frame of apoptosis, from the early to the late phase, which mimics the development of AD. © 2014 Springer Science+Business Media New York.


East D.A.,Royal Veterinary College University of London | Campanella M.,Royal Veterinary College University of London | Campanella M.,University College London | Campanella M.,European Brain Research Institute EBRi
Autophagy | Year: 2013

Calcium (Ca2+) has long been known as a ubiquitous intracellular second messenger, exploited by cells to control processes as diverse as development, proliferation, learning, muscle contraction and secretion. The spatial and temporal patterns of these Ca2+-associated signals, as well as their amplitude, is precisely controlled to create gradients of the ion, varying considerably depending on cell type and function. Tuning of intracellular Ca2+ is achieved in part by the buffering role of mitochondria, whose unperturbed function is essential for maintaining cellular energy balance. Quality of mitochondria is ensured by the process of targeted autophagy or mitophagy, which depends on a molecular cascade driving the catabolic process of autophagy toward damaged or deficient organelles for elimination via the lysosomal pathway. Nonspecific and targeted autophagy are highly regulated processes fundamental to cell growth and tissue homeostasis, allowing resources to be reallocated in nutrient-deprived cells as well as being instrumental in the repair of damaged organelles or the elimination of those in excess. Given the role of Ca2+ signaling in many fundamental cellular processes requiring precise regulation, the involvement of Ca 2+ in autophagy is still somewhat ill-defined, and only in the past few years has evidence emerged linking the two. This minireview aims to summarize recent work implicating Ca2+ as an important regulator of autophagy, outlining a role for Ca2+ that may be even more critical in the regulation of targeted mitochondrial autophagy. © 2013 Landes Bioscience.


Faccenda D.,Royal Veterinary College University of London | Tan C.H.,University College London | Seraphim A.,University College London | Duchen M.R.,University College London | And 3 more authors.
Cell Death and Differentiation | Year: 2013

Mitochondrial structure has a central role both in energy conversion and in the regulation of cell death. We have previously shown that IF 1 protects cells from necrotic cell death and supports cristae structure by promoting the oligomerisation of the F 1 F o-ATPsynthase. As IF 1 is upregulated in a large proportion of human cancers, we have here explored its contribution to the progression of apoptosis and report that an increased expression of IF 1, relative to the F 1 F o-ATPsynthase, protects cells from apoptotic death. We show that IF 1 expression serves as a checkpoint for the release of Cytochrome c (Cyt c) and hence the completion of the apoptotic program. We show that the progression of apoptosis engages an amplification pathway mediated by: (i) Cyt c-dependent release of ER Ca 2+, (ii) Ca 2+-dependent recruitment of the GTPase Dynamin-related protein 1 (Drp1), (iii) Bax insertion into the outer mitochondrial membrane and (iv) further release of Cyt c. This pathway is accelerated by suppression of IF 1 and delayed by its overexpression. IF 1 overexpression is associated with the preservation of mitochondrial morphology and ultrastructure, consistent with a central role for IF 1 as a determinant of the inner membrane architecture and with the role of mitochondrial ultrastructure in the regulation of Cyt c release. These data suggest that IF 1 is an antiapoptotic and potentially tumorigenic factor and may be a valuable predictor of responsiveness to chemotherapy. © 2013 Macmillan Publishers Limited All rights reserved.


Meli G.,European Brain Research Institute EBRI | Lecci A.,European Brain Research Institute EBRI | Manca A.,European Brain Research Institute EBRI | Krako N.,European Brain Research Institute EBRI | And 6 more authors.
Nature Communications | Year: 2014

A' 2 oligomers (A' 2Os) are crucially involved in Alzheimer's Disease (AD). However, the lack of selective approaches for targeting these polymorphic A' 2 assemblies represents a major hurdle in understanding their biosynthesis, traffic and actions in living cells. Here, we established a subcellularly localized conformational-selective interference (CSI) approach, based on the expression of a recombinant antibody fragment against A' 2Os in the endoplasmic reticulum (ER). By CSI, we can control extra- and intracellular pools of A' 2Os produced in an AD-relevant cell model, without interfering with the maturation and processing of the A' 2 precursor protein. The anti-A' 2Os intrabody selectively intercepts critical A' 2O conformers in the ER, modulating their assembly and controlling their actions in pathways of cellular homeostasis and synaptic signalling. Our results demonstrate that intracellular A' 2 undergoes pathological oligomerization through critical conformations formed inside the ER. This establishes intracellular A' 2Os as key targets for AD treatment and presents CSI as a potential targeting strategy. © 2014 Macmillan Publishers Limited. All rights reserved.


Bobba A.,CNR Institute of Neuroscience | Amadoro G.,CNR Institute of Neuroscience | Petragallo V.A.,CNR Institute of Neuroscience | Calissano P.,European Brain Research Institute EBRI | Atlante A.,CNR Institute of Neuroscience
Biochimica et Biophysica Acta - Bioenergetics | Year: 2013

To find out whether and how the adenine nucleotide translocator-1 (ANT-1) inhibition due to NH2htau and Aβ1-42 is due to an interplay between these two Alzheimer's peptides, ROS and ANT-1 thiols, use was made of mersalyl, a reversible alkylating agent of thiol groups that are oriented toward the external hydrophilic phase, to selectively block and protect, in a reversible manner, the -SH groups of ANT-1. The rate of ATP appearance outside mitochondria was measured as the increase in NADPH absorbance which occurs, following external addition of ADP, when ATP is produced by oxidative phosphorylation and exported from mitochondria in the presence of glucose, hexokinase and glucose-6-phosphate dehydrogenase. We found that the mitochondrial superoxide anions, whose production is induced at the level of Complex I by externally added Aβ1-42 and whose release from mitochondria is significantly reduced by the addition of the VDAC inhibitor DIDS, modify the thiol group/s present at the active site of mitochondrial ANT-1, impair ANT-1 in a mersalyl-prevented manner and abrogate the toxic effect of NH2htau on ANT-1 when Aβ1-42 is already present. A molecular mechanism is proposed in which the pathological Aβ-NH2htau interplay on ANT-1 in Alzheimer's neurons involves the thiol redox state of ANT-1 and the Aβ1-42-induced ROS increase. This result represents an important innovation because it suggests the possibility of using various strategies to protect cells at the mitochondrial level, by stabilizing or restoring mitochondrial function or by interfering with the energy metabolism providing a promising tool for treating or preventing AD. © 2013 Elsevier B.V.


Mendez P.,European Brain Research Institute EBRI
Neural plasticity | Year: 2011

Cortical structures of the adult mammalian brain are characterized by a spectacular diversity of inhibitory interneurons, which use GABA as neurotransmitter. GABAergic neurotransmission is fundamental for integrating and filtering incoming information and dictating postsynaptic neuronal spike timing, therefore providing a tight temporal code used by each neuron, or ensemble of neurons, to perform sophisticated computational operations. However, the heterogeneity of cortical GABAergic cells is associated to equally diverse properties governing intrinsic excitability as well as strength, dynamic range, spatial extent, anatomical localization, and molecular components of inhibitory synaptic connections that they form with pyramidal neurons. Recent studies showed that similarly to their excitatory (glutamatergic) counterparts, also inhibitory synapses can undergo activity-dependent changes in their strength. Here, some aspects related to plasticity and modulation of adult cortical and hippocampal GABAergic synaptic transmission will be reviewed, aiming at providing a fresh perspective towards the elucidation of the role played by specific cellular elements of cortical microcircuits during both physiological and pathological operations.


Mendez P.,European Brain Research Institute EBRI | Bacci A.,European Brain Research Institute EBRI
Neural Plasticity | Year: 2011

Cortical structures of the adult mammalian brain are characterized by a spectacular diversity of inhibitory interneurons, which use GABA as neurotransmitter. GABAergic neurotransmission is fundamental for integrating and filtering incoming information and dictating postsynaptic neuronal spike timing, therefore providing a tight temporal code used by each neuron, or ensemble of neurons, to perform sophisticated computational operations. However, the heterogeneity of cortical GABAergic cells is associated to equally diverse properties governing intrinsic excitability as well as strength, dynamic range, spatial extent, anatomical localization, and molecular components of inhibitory synaptic connections that they form with pyramidal neurons. Recent studies showed that similarly to their excitatory (glutamatergic) counterparts, also inhibitory synapses can undergo activity-dependent changes in their strength. Here, some aspects related to plasticity and modulation of adult cortical and hippocampal GABAergic synaptic transmission will be reviewed, aiming at providing a fresh perspective towards the elucidation of the role played by specific cellular elements of cortical microcircuits during both physiological and pathological operations. Copyright 2011 Pablo Méndez and Alberto Bacci.

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