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In the last two decades, there has been increasing evidence supporting non-neuronal cells as active contributors to neurodegenerative disorders. Among glial cells, astrocytes play a pivotal role in driving amyotrophic lateral sclerosis (ALS) progression, leading the scientific community to focus on the "astrocytic signature" in ALS. Here, we summarized the main pathological mechanisms characterizing astrocyte contribution to MN damage and ALS progression, such as neuroinflammation, mitochondrial dysfunction, oxidative stress, energy metabolism impairment, miRNAs and extracellular vesicles contribution, autophagy dysfunction, protein misfolding, and altered neurotrophic factor release. Since glutamate excitotoxicity is one of the most relevant ALS features, we focused on the specific contribution of ALS astrocytes in this aspect, highlighting the known or potential molecular mechanisms by which astrocytes participate in increasing the extracellular glutamate level in ALS and, conversely, undergo the toxic effect of the excessive glutamate. In this scenario, astrocytes can behave as "producers" and "targets" of the high extracellular glutamate levels, going through changes that can affect themselves and, in turn, the neuronal and non-neuronal surrounding cells, thus actively impacting the ALS course. Moreover, this review aims to point out knowledge gaps that deserve further investigation. [ABSTRACT FROM AUTHOR]

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease characterized by progressive degeneration of motor neurons (MNs). Astrocytes display a toxic phenotype in ALS, which results in MN damage. Glutamate (Glu)-mediated excitotoxicity and group I metabotropic glutamate receptors (mGluRs) play a pathological role in the disease progression. We previously demonstrated that in vivo genetic ablation or pharmacological modulation of mGluR5 reduced astrocyte activation and MN death, prolonged survival and ameliorated the clinical progression in the SOD1G93A mouse model of ALS. This study aimed to investigate in vitro the effects of mGluR5 downregulation on the reactive spinal cord astrocytes cultured from adult late symptomatic SOD1G93A mice. We observed that mGluR5 downregulation in SOD1G93A astrocytes diminished the cytosolic Ca2+ overload under resting conditions and after mGluR5 simulation and reduced the expression of the reactive glial markers GFAP, S100β and vimentin. In vitro exposure to an anti-mGluR5 antisense oligonucleotide or to the negative allosteric modulator CTEP also ameliorated the altered reactive astrocyte phenotype. Downregulating mGluR5 in SOD1G93A mice reduced the synthesis and release of the pro-inflammatory cytokines IL-1β, IL-6 and TNF-α and ameliorated the cellular bioenergetic profile by improving the diminished oxygen consumption and ATP synthesis and by lowering the excessive lactate dehydrogenase activity. Most relevantly, mGluR5 downregulation hampered the neurotoxicity of SOD1G93A astrocytes co-cultured with spinal cord MNs. We conclude that selective reduction in mGluR5 expression in SOD1G93A astrocytes positively modulates the astrocyte reactive phenotype and neurotoxicity towards MNs, further supporting mGluR5 as a promising therapeutic target in ALS. [ABSTRACT FROM AUTHOR]

Amyotrophic lateral sclerosis is an adult‐onset neurodegenerative disease that develops because of motor neuron death. Several mechanisms occur supporting neurodegeneration, including mitochondrial dysfunction. Recently, we demonstrated that the synaptosomes from the spinal cord of SOD1G93A mice, an in vitro model of presynapses, displayed impaired mitochondrial metabolism at early pre‐symptomatic stages of the disease, whereas perisynaptic astrocyte particles, or gliosomes, were characterized by mild energy impairment only at symptomatic stages. This work aimed to understand whether mitochondrial impairment is a consequence of upstream metabolic damage. We analyzed the critical pathways involved in glucose catabolism at presynaptic and perisynaptic compartments. Spinal cord and motor cortex synaptosomes from SOD1G93A mice displayed high activity of hexokinase and phosphofructokinase, key glycolysis enzymes, and of citrate synthase and malate dehydrogenase, key Krebs cycle enzymes, but did not display high lactate dehydrogenase activity, the key enzyme in lactate fermentation. This enhancement was evident in the spinal cord from the early stages of the disease and in the motor cortex at only symptomatic stages. Conversely, an increase in glycolysis and lactate fermentation activity, but not Krebs cycle activity, was observed in gliosomes from the spinal cord and motor cortex of SOD1G93A mice although only at the symptomatic stages of the disease. The cited enzymatic activities were enhanced in spinal cord and motor cortex homogenates, paralleling the time‐course of the effect observed in synaptosomes and gliosomes. The observed metabolic modifications might be considered an attempt to restore altered energetic balance and indicate that mitochondria represent the ultimate site of bioenergetic impairment. [ABSTRACT FROM AUTHOR]

The racemic mixture dimiracetam negatively modulates NMDA-induced glutamate release in rat spinal cord synaptosomal preparations and is orally effective in models of neuropathic pain. In this study, we compared the effects of dimiracetam, its R- or S-enantiomers, and the R:S 3:1 non-racemic mixture (MP-101). In vitro, dimiracetam was more potent than its R- or S-enantiomers in reducing the NMDA-induced [3H]D-aspartate release in rat spinal cord synaptosomes. Similarly, acute oral administration of dimiracetam was more effective than a single enantiomer in the sodium monoiodoacetate (MIA) paradigm of painful osteoarthritis. Then, we compared the in vitro effects of a broad range of non-racemic enantiomeric mixtures on the NMDA-induced [3H]D-aspartate release. Dimiracetam was a more potent blocker than each isolated enantiomer but the R:S 3:1 non-racemic mixture (MP-101) was even more potent than dimiracetam, with an IC50 in the picomolar range. In the chronic oxaliplatin-induced neuropathic pain model, MP-101 showed a significantly improved anti-neuropathic profile, and its effect continued one week after treatment suspension. MP-101 also performed better than dimiracetam in animal models of cognition and depression. Based on the benign safety and tolerability profile previously observed with racemic dimiracetam, MP-101 appears to be a novel, promising clinical candidate for the prevention and treatment of several neuropathic and neurological disorders. [ABSTRACT FROM AUTHOR]

• Visuo-haptic exploration impacts children's cross-sectioning abilities. • Children with visual-tactile exposure outperformed visually exploring peers in SBST. • Visual-haptic improvement emerges after 5 years old. • Sensory-motor and multisensory skills are pivotal for children's geometric learning. Cross-sectioning is a shape understanding task where the participants must infer and interpret the spatial features of three-dimensional (3D) solids by depicting their internal two-dimensional (2D) arrangement. An increasing body of research provides evidence of the crucial role of sensorimotor experience in acquiring these complex geometrical concepts. Here, we focused on how cross-sectioning ability emerges in young children and the influence of multisensory visuo-haptic experience in geometrical learning through two experiments. In Experiment 1, we compared the 3D printed version of the Santa Barbara Solids Test (SBST) with its classical paper version; in Experiment 2, we contrasted the children's performance in the SBST before and after the visual or visuo-haptic experience. In Experiment 1, we did not identify an advantage in visualizing 3D shapes over the classical 2D paper test. In contrast, in Experiment 2, we found that children who had the experience of a combination of visual and tactile information during the exploration phase improved their performance in the SBST compared with children who were limited to visual exploration. Our study demonstrates how practicing novel multisensory strategies improves children's understanding of complex geometrical concepts. This outcome highlights the importance of introducing multisensory experience in educational training and the need to make way for developing new technologies that could improve learning abilities in children. [ABSTRACT FROM AUTHOR]

Background and Purpose: The pathogenesis of amyotrophic lateral sclerosis (ALS) is not fully clarified, although excessive glutamate (Glu) transmission and the downstream cytotoxic cascades are major mechanisms for motor neuron death. Two metabotropic glutamate receptors (mGlu1 and mGlu5) are overexpressed in ALS and regulate cellular disease processes. Expression and function of mGlu5 receptors are altered at early symptomatic stages in the SOD1G93A mouse model of ALS and knockdown of mGlu5 receptors in SOD1G93A mice improved disease progression. Experimental Approach We treated male and female SOD1G93A mice with 2‐chloro‐4‐((2,5‐dimethyl‐1‐(4‐(trifluoromethoxy)phenyl)‐1H‐imidazol‐4‐yl)ethynyl)pyridine (CTEP), an orally available mGlu5 receptor negative allosteric modulator (NAM), using doses of 2 mg·kg−1 per 48 h or 4 mg·kg−1 per 24 h from Day 90, an early symptomatic disease stage. Disease progression was studied by behavioural and histological approaches. Key Results: CTEP dose‐dependently ameliorated clinical features in SOD1G93A mice. The lower dose increased survival and improved motor skills in female mice, with barely positive effects in male mice. Higher doses significantly ameliorated disease symptoms and survival in both males and females, females being more responsive. CTEP also reduced motor neuron death, astrocyte and microglia activation, and abnormal glutamate release in the spinal cord, with equal effects in male and female mice. No differences were also observed in CTEP access to the brain. Conclusion and Implications: Our results suggest that mGlu5 receptors are promising targets for the treatment of ALS and highlight mGlu5 receptor NAMs as effective pharmacological tools with translational potential. [ABSTRACT FROM AUTHOR]

Stress is a primary risk factor in the onset of neuropsychiatric disorders, including major depressive disorder (MDD). We have previously used the chronic mild stress (CMS) model of depression in male rats to show that CMS induces morphological, functional, and molecular changes in the hippocampus of vulnerable animals, the majority of which were recovered using acute subanesthetic ketamine in just 24 h. Here, we focused our attention on the medial prefrontal cortex (mPFC), a brain area regulating emotional and cognitive functions, and asked whether vulnerability/resilience to CMS and ketamine antidepressant effects were associated with molecular and functional changes in the mPFC of rats. We found that most alterations induced by CMS in the mPFC were selectively observed in stress-vulnerable animals and were rescued by acute subanesthetic ketamine, while others were found only in resilient animals or were induced by ketamine treatment. Importantly, only a few of these modifications were also previously demonstrated in the hippocampus, while most are specific to mPFC. Overall, our results suggest that acute antidepressant ketamine rescues brain-area-specific glutamatergic changes induced by chronic stress. [ABSTRACT FROM AUTHOR]

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease with no effective cure. Astrocytes display a toxic phenotype in ALS and contribute to motoneuron (MN) degeneration. Modulating astrocytes' neurotoxicity can reduce MN death. Our previous studies showed the beneficial effect of mesenchymal stem cell (MSC) administration in SOD1G93A ALS mice, but the mechanisms are still unclear. We postulated that the effects could be mediated by extracellular vesicles (EVs) secreted by MSCs. We investigated, by immunohistochemical, molecular, and in vitro functional analyses, the activity of MSC-derived EVs on the pathological phenotype and neurotoxicity of astrocytes isolated from the spinal cord of symptomatic SOD1G93A mice and human astrocytes (iAstrocytes) differentiated from inducible neural progenitor cells (iNPCs) of ALS patients. In vitro EV exposure rescued mouse and human ALS astrocytes' neurotoxicity towards MNs. EVs significantly dampened the pathological phenotype and neuroinflammation in SOD1G93A astrocytes. In iAstrocytes, exposure to EVs increased the antioxidant factor Nrf2 and reduced reactive oxygen species. We previously found nine miRNAs upregulated in MSC-derived EVs. Here, the transfection of SOD1G93A astrocytes with single miRNA mimics reduced astrocytes' activation and the expression of neuroinflammatory factors. Moreover, miR-466q and miR-467f mimics downregulate Mapk11, while miR-466m-5p and miR-466i-3p mimics promote the nuclear translocation of Nrf2. In iAstrocytes, transfection with miR-29b-3p mimic upregulated NQO1 antioxidant activity and reduced neurotoxicity towards MNs. MSC-derived EVs modulate astrocytes' reactive phenotype and neurotoxicity through anti-inflammatory and antioxidant-shuttled miRNAs, thus representing a therapeutic strategy in ALS. [ABSTRACT FROM AUTHOR]

Abstract: Carbon dioxide is more and more pointed out as one of the factors mostly responsible of climate changes. As a consequence the reduction of CO2 emissions, especially in the energy generation field, is becoming a worldwide must. This paper presents an overview on the main issues that are expected to affect, from this standpoint, power generation scenario and a spur for a critical comparison among ways to capture CO2 by proposing new aspects to be considered within the evaluation criteria. In particular attention is drawn on the fully innovative opportunities that are offered by Molten Carbonate Fuel Cells (MCFCs) as a unique option suitable to effectively combine carbon capture from thermal plants and typical benefits of hydrogen and fuel cell power generation. As an example, such a new option is compared with one of the most common technologies forecast for reducing carbon dioxide emissions and relevant results are shortly presented. [Copyright &y& Elsevier]

Background Management of patients with oncohaematological disorders such as monoclonal gammopathy of undetermined significance (MGUS) is a frequent problem in pre-transplant work-up. Insights on disease progression and long-term functional outcomes are still lacking in this setting. Methods This was a retrospective analysis on all patients with MGUS who underwent kidney transplant (KT) at our centre between 1 January 2000 and 31 December 2017 (cases, n  = 65). Patients were matched with a control group (KTs with similar characteristics but without history of haematological disease, controls, n  = 1079). Primary endpoints were graft and patient survival; secondary endpoints were causes of graft failure, patient death, occurrence of allograft rejection, post-transplant neoplasia (not correlated to previous disorder) and/or infectious episodes. Results The MGUS and control groups had a similar mean age [60 (29–79) versus 55.2 (19.3–79.5) years, respectively] and percentage of males (69.2% versus 64.6%, respectively). Median follow-up time since KT was 3.5 years (0–14) in cases and 8.3 years (0–14.9) in controls. All MGUS patients underwent KT following extensive multidiscliplinary investigations. No differences were found between cases and controls regarding patient and graft survival or post-transplant complications except for lower incidence of infections (58.7% versus 69.8%, P = 0.019) and increased use of mTOR inhbitors (30.3% versus 14.7%, P = 0.001) in MGUS. MGUS isotype did not influence graft and patient survival. The absence of difference in patients and graft survival was also confirmed in an adjunctive analysis where MGUS were compared with controls (ratio 1:2) matched for recipient age, gender, number of transplantations and transplant period. Conclusion Patients with MGUS may undergo KT without significantly increased risks of complications, provided that appropriate diagnostic procedures are carefully followed. Multidiscipline-based studies are crucial for establishing well designed pre- and post-transplant protocols for the best management of patients with coexisting MGUS and end-stage renal disease. [ABSTRACT FROM AUTHOR]

Despite type 2 diabetes mellitus (T2D) is commonly considered a detrimental factor in dialysis, its clear effect on morbidity and mortality on waitlisted patients for kidney transplant (KT) has never been completely elucidated. We performed a retrospective analysis on 714 patients admitted to wait-list (WL) for their first kidney transplant from 2005 to 2010. Clinical characteristics at registration in WL (age, body mass index -BMI-, duration and modality of dialysis, underlying nephropathy, coronary artery -CAD- and/or peripheral vascular disease), mortality rates, and effective time on WL were investigated and compared according to T2D status (presence/absence). Data about therapy and management of T2D were also considered. At the time of WL registration T2D patients (n = 86) were older than non-T2D (n = 628) (58.7 ± 8.6 years vs 51.3 ± 12.9) with higher BMI (26.2 ± 3.8 kg/m2 vs 23.8 ± 3.6), more frequent history of CAD (33.3% vs 9.8%) and peripheral vascular disease (25.3% vs 5.8%) (p < 0.001 for all analyses). Considering overall population, T2D patients had reduced survival vs non-T2D (p < 0.001). Transplanted patients showed better survival in both T2D and non-T2D groups despite transplant rate are lower in T2D (75.6% vs 85.8%, p < 0.001). T2D was also associated to similar waiting time but longer periods between dialysis start and registration in WL (1.6 years vs 1.2, p = 0.008), comorbidity-related suspension from WL (571 days vs 257, p = 0.002), and increased mortality rate (33.7% vs 13.9% in the overall population, p < 0.001). In T2D patients admitted to WL, an history of vascular disease was significantly associated to low patient survival (p = 0.019). In conclusion, T2D significantly affects survival also on waitlisted patients. Allocation policies in T2D patients may be adjusted according to increased risk of mortality and WL suspension due to comorbidities. [ABSTRACT FROM AUTHOR]

Background: We recently reported that enhanced [18F]-fluorodeoxyglucose (FDG) uptake in skeletal muscles predicts disease aggressiveness in patients with amyotrophic lateral sclerosis (ALS). The present experimental study aimed to assess whether this predictive potential reflects the link between FDG uptake and redox stress that has been previously reported in different tissues and disease models. Methods: The study included 15 SOD1G93A mice (as experimental ALS model) and 15 wildtype mice (around 120 days old). Mice were submitted to micro-PET imaging. Enzymatic pathways and response to oxidative stress were evaluated in harvested quadriceps and hearts by biochemical, immunohistochemical, and immunofluorescence analysis. Colocalization between the endoplasmic reticulum (ER) and the fluorescent FDG analog 2-[N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino]-2-deoxyglucose (2-NBDG) was performed in fresh skeletal muscle sections. Finally, mitochondrial ultrastructure and bioenergetics were evaluated in harvested quadriceps and hearts. Results: FDG retention was significantly higher in hindlimb skeletal muscles of symptomatic SOD1G93A mice with respect to control ones. This difference was not explained by any acceleration in glucose degradation through glycolysis or cytosolic pentose phosphate pathway (PPP). Similarly, it was independent of inflammatory infiltration. Rather, the high FDG retention in SOD1G93A skeletal muscle was associated with an accelerated generation of reactive oxygen species. This redox stress selectively involved the ER and the local PPP triggered by hexose-6P-dehydrogenase. ER involvement was confirmed by the colocalization of the 2-NBDG with a vital ER tracker. The oxidative damage in transgenic skeletal muscle was associated with a severe impairment in the crosstalk between ER and mitochondria combined with alterations in mitochondrial ultrastructure and fusion/fission balance. The expected respiratory damage was confirmed by a deceleration in ATP synthesis and oxygen consumption rate. These same abnormalities were represented to a markedly lower degree in the myocardium, as a sample of non-voluntary striated muscle. Conclusion: Skeletal muscle of SOD1G93A mice reproduces the increased FDG uptake observed in ALS patients. This finding reflects the selective activation of the ER-PPP in response to significant redox stress associated with alterations of mitochondrial ultrastructure, networking, and connection with the ER itself. This scenario is less severe in cardiomyocytes suggesting a relevant role for either communication with synaptic plaque or contraction dynamics. [ABSTRACT FROM AUTHOR]

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease due to motor neuron (MN) loss. The mechanisms causing selective MN death are largely unknown, thus prejudicing successful pharmacological treatments. Major causes of MN damage are effects downstream of the abnormal glutamate (Glu) neurotransmission. Group I metabotropic Glu receptors (mGluR1, mGluR5) actively contribute to the excitotoxicity in ALS and represent druggable molecular targets. We previously demonstrated that halving mGluR1 or mGluR5 expression in the widely studied SOD1 G93A mouse model of ALS had a positive impact on disease onset, clinical progression and survival, as well as on cellular and biochemical parameters altered in ALS. Whereas these effects were similar in female and male mGluR1 heterozygous SOD1 G93A mice, only male mGluR5 heterozygous SOD1 G93A mice showed improved motor skills during disease progression. To further validate the role of Group I mGluRs in ALS, we generated in this study mGluR1 or mGluR5 null mice expressing the SOD1 G93A mutation (SOD1 G93A Grm1 crv4/crv4 or SOD1 G93A Grm5 −/− , respectively). SOD1 G93A Grm1 crv4/crv4 mice showed early and progressive motor impairments and died even before SOD1 G93A mice, while SOD1 G93A Grm5 −/− mice exhibited delayed disease onset, longer survival, and ameliorated motor skills than SOD1 G93A mice. No difference between female and male SOD1 G93A Grm5 −/− mice were observed. These effects were associated with enhanced MN preservation and decreased astrocytic and microglial activation. Our results strongly support the assumption that constitutively lowering of mGluR5 expression has a positive impact in mice with ALS by counteracting the abnormal Glu transmission and this could be a potentially effective pharmacological target in ALS. Unlabelled Image • mGluR5 deletion delays clinical onset and prolongs survival in SOD1 G93A mice. • mGluR5 deletion improves motor skills in SOD1 G93A mice during disease progression. • mGluR5 deletion reduces motor neuron death in SOD1 G93A mice. • mGluR5 deletion reduces astrogliosis and microgliosis in SOD1 G93A mice. [ABSTRACT FROM AUTHOR]

Amyotrophic lateral sclerosis (ALS) is a fatal, multigenic, multifactorial, and non-cell autonomous neurodegenerative disease characterized by upper and lower motor neuron loss. Several genetic mutations lead to ALS development and many emerging gene mutations have been discovered in recent years. Over the decades since 1990, several animal models have been generated to study ALS pathology including both vertebrates and invertebrates such as yeast, worms, flies, zebrafish, mice, rats, guinea pigs, dogs, and non-human primates. Although these models show different peculiarities, they are all useful and complementary to dissect the pathological mechanisms at the basis of motor neuron degeneration and ALS progression, thus contributing to the development of new promising therapeutics. In this review, we describe the up to date and available ALS genetic animal models, classified by the different genetic mutations and divided per species, pointing out their features in modeling, the onset and progression of the pathology, as well as their specific pathological hallmarks. Moreover, we highlight similarities, differences, advantages, and limitations, aimed at helping the researcher to select the most appropriate experimental animal model, when designing a preclinical ALS study. [ABSTRACT FROM AUTHOR]

As part of its climate change mitigation initiative, BP is evaluating technologies for the separation and capture of CO2 from combustion sources, for subsequent geologic storage. Ansaldo Fuel Cells S.p.A. is developing molten carbonate fuel cell (MCFC) technology targeted at industrial applications from 50 kW to 10 MW. This paper describes the conceptual design of a hybrid MCFC system to generate power and simultaneously capture CO2 from small (<10 MW) gas turbine exhaust streams. Initial modeling studies indicated that a 1.6 MW MCFC could reduce the CO2 emissions from a 4.6 MW gas turbine by 50% on a per kWh basis. Experimental studies are in progress to understand the system behaviour, operating envelope and impact of contaminants. Initial data from these investigations are presented, which confirm that the fuel cell can operate at sub-optimal CO2 levels with limited loss in power and efficiency. [Copyright &y& Elsevier]

Glutamate (Glu)-mediated excitotoxicity is a major cause of amyotrophic lateral sclerosis (ALS) and our previous work highlighted that abnormal Glu release may represent a leading mechanism for excessive synaptic Glu. We demonstrated that group I metabotropic Glu receptors (mGluR1, mGluR5) produced abnormal Glu release in SOD1G93A mouse spinal cord at a late disease stage (120 days). Here, we studied this phenomenon in pre-symptomatic (30 and 60 days) and early-symptomatic (90 days) SOD1G93A mice. The mGluR1/5 agonist (S)-3,5-Dihydroxyphenylglycine (3,5-DHPG) concentration dependently stimulated the release of [3H]d-Aspartate ([3H]d-Asp), which was comparable in 30- and 60-day-old wild type mice and SOD1G93A mice. At variance, [3H]d-Asp release was significantly augmented in 90-day-old SOD1G93A mice and both mGluR1 and mGluR5 were involved. The 3,5-DHPG-induced [3H]d-Asp release was exocytotic, being of vesicular origin and mediated by intra-terminal Ca2+ release. mGluR1 and mGluR5 expression was increased in Glu spinal cord axon terminals of 90-day-old SOD1G93A mice, but not in the whole axon terminal population. Interestingly, mGluR1 and mGluR5 were significantly augmented in total spinal cord tissue already at 60 days. Thus, function and expression of group I mGluRs are enhanced in the early-symptomatic SOD1G93A mouse spinal cord, possibly participating in excessive Glu transmission and supporting their implication in ALS. Please define all abbreviations the first time they appear in the abstract, the main text, and the first figure or table caption. [ABSTRACT FROM AUTHOR]