Publications by authors named "Patrizia Popoli"

72 Publications

P2X7 Receptor Agonist 2'(3')-O-(4-Benzoylbenzoyl)ATP Differently Modulates Cell Viability and Corticostriatal Synaptic Transmission in Experimental Models of Huntington's Disease.

Front Pharmacol 2020 19;11:633861. Epub 2021 Feb 19.

National Center for Drug Research and Evaluation, Istituto Superiore di Sanità, Rome, Italy.

Huntington's disease (HD) is a life-threatening neurodegenerative disorder. Altered levels and functions of the purinergic ionotropic P2X7 receptors (P2X7Rs) have been found in animal and cellular models of HD, suggesting their possible role in the pathogenesis of the disease; accordingly, the therapeutic potential of P2X7R antagonists in HD has been proposed. Here we further investigated the effects of P2X7R ligands in and HD experimental models. In ST14A/Q120 rat striatal cells, we found a reduction of P2X7R expression; however, the P2X7R agonist 2'(3')-O-(4-benzoylbenzoyl)adenosine-5'-triphosphate (BzATP) induced cellular death, and this effect was fully reversed by the antagonist periodate-oxidized adenosine 5'-triphosphate (OxATP). Moreover, in corticostriatal slices from symptomatic R6/2 mice, BzATP reduced the synaptic transmission to a larger extent than in wild-type (WT) mice. Such an effect was accompanied by a concomitant increase of the paired-pulse ratio, suggesting a presynaptic inhibitory action. This was confirmed to be the case, since while the effects of BzATP were unaffected by the P2X7R antagonist OxATP, they were blocked by the adenosine A receptor (AR) antagonist 8-cyclopentyl-1,3-dipropylxanthine (DPCPX), suggesting possible BzATP hydrolysis to 2'(3')-O-(4-benzoylbenzoyl)adenosine (Bz-adenosine) and consequent activation of ARs as a mechanism. Taken together, these data point out that 1) P2X7R expression and activity are confirmed to be altered in the presence of HD mutation; 2) in some experimental settings, such an abnormal functioning can be ascribed to presynaptic ARs activation.
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http://dx.doi.org/10.3389/fphar.2020.633861DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7933594PMC
February 2021

Adenosine A receptor inhibition reduces synaptic and cognitive hippocampal alterations in Fmr1 KO mice.

Transl Psychiatry 2021 Feb 5;11(1):112. Epub 2021 Feb 5.

National Center for Drug Research and Evaluation, Istituto Superiore di Sanità, Rome, Italy.

In fragile X syndrome (FXS) the lack of the fragile X mental retardation protein (FMRP) leads to exacerbated signaling through the metabotropic glutamate receptors 5 (mGlu5Rs). The adenosine A receptors (ARs), modulators of neuronal damage, could play a role in FXS. A synaptic colocalization and a strong permissive interaction between A and mGlu5 receptors in the hippocampus have been previously reported, suggesting that blocking ARs might normalize the mGlu5R-mediated effects of FXS. To study the cross-talk between A and mGlu5 receptors in the absence of FMRP, we performed extracellular electrophysiology experiments in hippocampal slices of Fmr1 KO mouse. The depression of field excitatory postsynaptic potential (fEPSPs) slope induced by the mGlu5R agonist CHPG was completely blocked by the AR antagonist ZM241385 and strongly potentiated by the AR agonist CGS21680, suggesting that the functional synergistic coupling between the two receptors could be increased in FXS. To verify if chronic AR blockade could reverse the FXS phenotypes, we treated the Fmr1 KO mice with istradefylline, an AR antagonist. We found that hippocampal DHPG-induced long-term depression (LTD), which is abnormally increased in FXS mice, was restored to the WT level. Furthermore, istradefylline corrected aberrant dendritic spine density, specific behavioral alterations, and overactive mTOR, TrkB, and STEP signaling in Fmr1 KO mice. Finally, we identified AR mRNA as a target of FMRP. Our results show that the pharmacological blockade of ARs partially restores some of the phenotypes of Fmr1 KO mice, both by reducing mGlu5R functioning and by acting on other AR-related downstream targets.
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http://dx.doi.org/10.1038/s41398-021-01238-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7864914PMC
February 2021

Tocilizumab for patients with COVID-19 pneumonia. The single-arm TOCIVID-19 prospective trial.

J Transl Med 2020 10 21;18(1):405. Epub 2020 Oct 21.

Department of Mental Health and Preventive Medicine, Università degli Studi della Campania Luigi Vanvitelli, Caserta, Italy.

Background: Tocilizumab blocks pro-inflammatory activity of interleukin-6 (IL-6), involved in pathogenesis of pneumonia the most frequent cause of death in COVID-19 patients.

Methods: A multicenter, single-arm, hypothesis-driven trial was planned, according to a phase 2 design, to study the effect of tocilizumab on lethality rates at 14 and 30 days (co-primary endpoints, a priori expected rates being 20 and 35%, respectively). A further prospective cohort of patients, consecutively enrolled after the first cohort was accomplished, was used as a secondary validation dataset. The two cohorts were evaluated jointly in an exploratory multivariable logistic regression model to assess prognostic variables on survival.

Results: In the primary intention-to-treat (ITT) phase 2 population, 180/301 (59.8%) subjects received tocilizumab, and 67 deaths were observed overall. Lethality rates were equal to 18.4% (97.5% CI: 13.6-24.0, P = 0.52) and 22.4% (97.5% CI: 17.2-28.3, P < 0.001) at 14 and 30 days, respectively. Lethality rates were lower in the validation dataset, that included 920 patients. No signal of specific drug toxicity was reported. In the exploratory multivariable logistic regression analysis, older age and lower PaO2/FiO2 ratio negatively affected survival, while the concurrent use of steroids was associated with greater survival. A statistically significant interaction was found between tocilizumab and respiratory support, suggesting that tocilizumab might be more effective in patients not requiring mechanical respiratory support at baseline.

Conclusions: Tocilizumab reduced lethality rate at 30 days compared with null hypothesis, without significant toxicity. Possibly, this effect could be limited to patients not requiring mechanical respiratory support at baseline. Registration EudraCT (2020-001110-38); clinicaltrials.gov (NCT04317092).
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http://dx.doi.org/10.1186/s12967-020-02573-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7576974PMC
October 2020

TOCIVID-19 - A multicenter study on the efficacy and tolerability of tocilizumab in the treatment of patients with COVID-19 pneumonia. Study protocol.

Contemp Clin Trials 2020 11 6;98:106165. Epub 2020 Oct 6.

Istituto Nazionale Tumori, IRCCS, Fondazione G. Pascale, Napoli, Italy. Electronic address:

Background: Pneumonia is the most frequent complication of COVID-19, due to an aberrant host immune response that is associated with an acute respiratory distress syndrome, and, in most critical patients, with a "cytokine storm". IL-6 might play a key role in the cytokine storm and might be a potential target to treat severe and critical COVID-19. Tocilizumab is a recombinant humanized monoclonal antibody, directed against IL-6 receptor.

Methods: This multicentre study project includes a single-arm phase 2 study and a further parallel cohort, enrolling hospitalized patients with COVID-19 pneumonia and oxygen saturation at rest in ambient air ≤93% or requiring respiratory support. Patients receive tocilizumab 8 mg/kg (up to 800 mg) as one intravenous administration. A second administration (same dose) after 12 h is optional. Two-week and one-month lethality rates are the co-primary endpoints. Sample size planned for the phase 2 study is 330 patients. The parallel cohort will include patients who cannot enter the phase 2 study because being intubated from more than 24 h, or having already received tocilizumab, or the phase 2 study has reached sample size. Primary analysis will include patients enrolled in the phase 2 study. Results of the primary analysis will be validated in the prospective cohort of patients consecutively registered after phase 2 closure from March 20 to March 24, who were potentially eligible for the phase 2 study.

Conclusion: This trial aims to verify the safety and efficacy of tocilizumab in the Italian population with COVID-19 pneumonia and respiratory impairment. EudraCT Number: 2020-001110-38; Clinicaltrials.gov ID NCT04317092.
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http://dx.doi.org/10.1016/j.cct.2020.106165DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7536129PMC
November 2020

The activity of the Striatal-enriched protein tyrosine phosphatase in neuronal cells is modulated by adenosine A receptor.

J Neurochem 2020 02 10;152(3):284-298. Epub 2019 Oct 10.

National Centre for Drug Research and Evaluation, Istituto Superiore di Sanità, Rome, Italy.

We recently demonstrated that a tonic activation of adenosine A receptors (A Rs) is required for cocaine-induced synaptic depression and increase in the activity of STriatal-Enriched protein tyrosine Phosphatase (STEP). In this study, we elaborated on the relationship between A R and STEP using genetic, pharmacological, and cellular tools. We found that the activities of protein tyrosine phosphatases (PTPs), and in particular of STEP, are significantly increased in the striatum and hippocampus of a transgenic rat strain over-expressing the neuronal A R (NSEA ) with respect to wild-type (WT) rats. Moreover the selective A R agonist 4-[2-[[6-Amino-9-(N-ethyl-β-d-ribofuranuronamidosyl)-9H-purin-2-yl]amino]ethyl]benzenepropanoic acid hydrochloride up-regulates PTPs and STEP activities in WT but not in NSEA rats, while the selective A R antagonist 4-(-2-[7-amino-2-{2-furyl}{1,2,4}triazolo{2,3-a} {1,3,5}triazin-5-yl-amino]ethyl)phenol restores the tyrosine phosphatase activities in NSEA , having no effects in WT rats. In addition, while cocaine induced the activation of PTP and STEP in WT rats, it failed to increase phosphatase activity in NSEA rats. A Rs modulate STEP activity also in the SH-SY5Y neuroblastoma cell line, where a calcium-dependent calcineurin/PP1 pathway was found to play a major role. In summary, the present study identified a novel interaction between A R and STEP that could have important clinical implications, since STEP has emerged as key regulator of signaling pathways involved in neurodegenerative and neuropsychiatric diseases and A Rs are considered a promising target for the development of therapeutic strategies for different diseases of the central nervous system. Read the Editorial Highlight for this article on page 270.
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http://dx.doi.org/10.1111/jnc.14866DOI Listing
February 2020

Adenosine A receptor stimulation restores cell functions and differentiation in Niemann-Pick type C-like oligodendrocytes.

Sci Rep 2019 07 5;9(1):9782. Epub 2019 Jul 5.

Research Coordination and Support Service, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161, Rome, Italy.

Niemann Pick type C (NPC) disease is a rare neurovisceral disorder. Mutations in npc1 gene induce an intracellular accumulation of unesterified cholesterol in the endosomal/lysosomal system causing cell death. We recently showed that stimulation of adenosine A receptors (AR) restores cholesterol accumulation in late endosomes/lysosomes in human NPC fibroblasts and neural cell lines transiently transfected with NPC1 siRNA, suggesting that these receptors might be targeted to contrast the disease. Since NPC1 disease is characterized by dysmyelination and maturational arrest of oligodendrocyte progenitors (OPs), in this study, we investigated whether AR stimulation could promote oligodendrocyte differentiation and myelin formation, thus overcoming these important neurological abnormalities. We developed a NPC1 pharmacological model, in which primary cultures of OPs are exposed to a cholesterol transport inhibitor to induce a NPC1-like phenotype characterized by several typical features such as (i) cholesterol accumulation, (ii) altered mitochondrial morphology and membrane potential, (iii) defect of autophagy and (iv) maturation arrest. The AR agonist CGS21680 normalized all NPC1-like features. The ability of CGS21680 of rescuing OP from maturational arrest and promoting their differentiation to mature OL, suggests that AR stimulation might be exploited to correct dysmyelination in NPC1, further supporting their therapeutic potential in the disease.
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http://dx.doi.org/10.1038/s41598-019-46268-8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6611770PMC
July 2019

Adenosine A receptor as potential therapeutic target in neuropsychiatric disorders.

Pharmacol Res 2019 09 2;147:104338. Epub 2019 Jul 2.

National Centre for Drug Research and Evaluation, Istituto Superiore di Sanità, Roma, Italy.

Adenosine A receptor (AR) is a G-protein coupled receptor that regulates several important functions in the central nervous system. Large amount of preclinical data suggests that the AR could represent a target for the development of new therapeutic strategies for different neuropsychiatric conditions. In this review we will recapitulate and discuss the most relevant studies on the role of ARs in neurodegenerative, neurodevelopmental and psychiatric diseases, which led to suggest a therapeutic use of AR agonists in certain diseases (Niemann-Pick disease, autism-spectrum disorders, schizophrenia) and AR antagonists in others (Alzheimer's disease, Parkinson's disease, attention-deficit hyperactivity disorder, fragile X syndrome, depression, anxiety). Moreover, we will try to analyze which are the main obstacles to the conduction of clinical trials with AR ligands for the treatment of neuropsychiatric disease.
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http://dx.doi.org/10.1016/j.phrs.2019.104338DOI Listing
September 2019

Modulating P1 Adenosine Receptors in Disease Progression of SOD1 Mutant Mice.

Neurochem Res 2019 May 12;44(5):1037-1042. Epub 2019 Feb 12.

National Center for Drug Research and Evaluation, Istituto Superiore di Sanità, Viale Regina Elena, 299, 00161, Rome, Italy.

Amyotrophic lateral sclerosis (ALS) is a fatal progressing neurodegenerative disease; to date, despite the intense research effort, only two therapeutic options, with very limited effects, are available. The purinergic system has been indicated as a possible new therapeutic target for ALS, but the results are often contradictory and generally confused. The present study was designed to determine whether P1 adenosine receptor ligands affected disease progression in a transgenic model of ALS. SOD1 mice were chronically treated, from presymptomatic stage, with a selective adenosine A receptor agonist (CGS21680), antagonist (KW6002) or the A receptor antagonist DPCPX. Body weight, motor performance and survival time were evaluated. The results showed that neither the stimulation nor the blockade of adenosine A receptors modified the progressive loss of motor skills or survival of mSOD1 mice. Conversely, blockade of adenosine A receptors from the presymptomatic stage significantly attenuated motor disease progression and induced a non-significant increase of median survival in ALS mice. Our data confirm that the modulation of adenosine receptors can elicit very different (and even opposite) effects during the progression of ALS course, thus strengthens the importance of further studies to elucidated their real therapeutic potential in this pathology.
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http://dx.doi.org/10.1007/s11064-019-02745-0DOI Listing
May 2019

Neuroprotective potential of adenosine A receptor partial agonists in experimental models of cerebral ischemia.

J Neurochem 2019 04 11;149(2):211-230. Epub 2019 Feb 11.

National Center for Drug Research and Evaluation, Istituto Superiore di Sanità, Rome, Italy.

Cerebral ischemia is the second most common cause of death and a major cause of disability worldwide. Available therapies are based only on anticoagulants or recombinant tissue plasminogen activator. Extracellular adenosine increases during ischemia and acts as a neuroprotective endogenous agent mainly by activating adenosine A receptors (A Rs) which control calcium influx, glutamate release, membrane potential, and metabolism. Accordingly, in many experimental paradigms it has been already demonstrated that the stimulation of A R with full agonists is able to reduce ischemia-related structural and functional brain damage; unfortunately, cardiovascular side effects and desensitization of A R induced by these compounds have strongly limited their exploitation in stroke therapy so far. Among the newly emerging compounds, A R partial agonists could be almost free of side effects and equally effective. Therefore, we decided to evaluate the neuroprotective potential of two A R partial agonists, namely 2'-dCCPA and 3'-dCCPA, in in vitro and ex vivo experimental models of cerebral ischemia. Within the experimental paradigm of oxygen-glucose deprivation in vitro in human neuroblastoma (SH-SY5Y) cells both A R partial agonists increased cell viability. Considering the high level of expression of A Rs in the hippocampus and the susceptibility of CA1 region to hypoxia, we performed electrophysiological experiments in this subfield. The application of 7 min of oxygen-glucose deprivation constantly produces an irreversible synaptic failure in all the C57Bl/6 mice hippocampal slices evaluated; both tested compounds allowed a significant recovery of synaptic transmission. These findings demonstrate that A R and its partial agonists are still of interest for cerebral ischemia therapy. OPEN SCIENCE BADGES: This article has received a badge for *Open Materials* because it provided all relevant information to reproduce the study in the manuscript. The complete Open Science Disclosure form for this article can be found at the end of the article. More information about the Open Practices badges can be found at https://cos.io/our-services/open-science-badges/.
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http://dx.doi.org/10.1111/jnc.14660DOI Listing
April 2019

The Role of Adenosine Tone and Adenosine Receptors in Huntington's Disease.

J Caffeine Adenosine Res 2018 Jun;8(2):43-58

National Center for Drug Research and Evaluation, Istituto Superiore di Sanità, Rome, Italy.

Huntington's disease (HD) is a hereditary neurodegenerative disorder caused by a mutation in the IT15 gene that encodes for the huntingtin protein. Mutated hungtingtin, although widely expressed in the brain, predominantly affects striato-pallidal neurons, particularly enriched with adenosine A receptors (AR), suggesting a possible involvement of adenosine and AR is the pathogenesis of HD. In fact, polymorphic variation in the gene influences the age at onset in HD, and AR dynamics is altered by mutated huntingtin. Basal levels of adenosine and adenosine receptors are involved in many processes critical for neuronal function and homeostasis, including modulation of synaptic activity and excitotoxicity, the control of neurotrophin levels and functions, and the regulation of protein degradation mechanisms. In the present review, we critically analyze the current literature involving the effect of altered adenosine tone and adenosine receptors in HD and discuss why therapeutics that modulate the adenosine system may represent a novel approach for the treatment of HD.
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http://dx.doi.org/10.1089/caff.2018.0006DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6049521PMC
June 2018

Neuronal adenosine A receptor overexpression is neuroprotective towards 3-nitropropionic acid-induced striatal toxicity: a rat model of Huntington's disease.

Purinergic Signal 2018 09 16;14(3):235-243. Epub 2018 May 16.

National Center for Drug Research and Evaluation, Istituto Superiore di Sanità, Viale Regina Elena, 299, 00161, Rome, Italy.

The A adenosine receptor (AR) is widely distributed on different cellular types in the brain, where it exerts a broad spectrum of pathophysiological functions, and for which a role in different neurodegenerative diseases has been hypothesized or demonstrated. To investigate the role of neuronal ARs in neurodegeneration, we evaluated in vitro and in vivo the effect of the neurotoxin 3-nitropropionic acid (3-NP) in a transgenic rat strain overexpressing ARs under the control of the neural-specific enolase promoter (NSEA rats). We recorded extracellular field potentials (FP) in corticostriatal slice and found that the synaptotoxic effect of 3-NP was significantly reduced in NSEA rats compared with wild-type animals (WT). In addition, after exposing corticostriatal slices to 3-NP 10 mM for 2 h, we found that striatal cell viability was significantly higher in NSEA rats compared to control rats. These in vitro results were confirmed by in vivo experiments: daily treatment of female rats with 3-NP 10 mg/kg for 8 days induced a selective bilateral lesion in the striatum, which was significantly reduced in NSEA compared to WT rats. These results demonstrate that the overexpression of the AR selectively at the neuronal level reduced 3-NP-induced neurodegeneration, and suggest an important function of the neuronal AR in the modulation of neurodegeneration.
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http://dx.doi.org/10.1007/s11302-018-9609-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6107463PMC
September 2018

The adenosine A receptor agonist T1-11 ameliorates neurovisceral symptoms and extends the lifespan of a mouse model of Niemann-Pick type C disease.

Neurobiol Dis 2018 02 25;110:1-11. Epub 2017 Oct 25.

National Center for Drug Research and Evaluation, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161 Rome, Italy.

Niemann-Pick C is a fatal neurovisceral disorder caused, in 95% of cases, by mutation of NPC1 gene. Therapeutic options are extremely limited and new "druggable" targets are highly warranted. We previously demonstrated that the stimulation of the adenosine A receptor (AR) normalized the pathological phenotype of cellular models of NPC1. Since the validation of ARs as a therapeutic target for NPC1 can be obtained only conducting studies in in vivo models of the disease, in the present paper, the effects of two agonists of ARs were evaluated in the mouse model Balb/c Npc1, hereafter indicated as NPC1-/-. The agonists CGS21680 (2.5 and 5mg/kg/day by intraperitoneal injection) and T1-11 (50mg/kg/day in drinking water) were administered at a presymptomatic stage of the disease of NPC1-/- mice (PN28 and PN30, respectively); the experimental groups were the following: vehicle-treated WT mice (N=16 for both CGS and T1-11 treatments); vehicle-treated NPC1-/- mice (N=14 for CGS and 12 for T1-11 treatment); CGS-treated NPC1-/- mice (N=7) and T1-11-treated NPC1-/- mice (N=11). The efficacy of the treatments was evaluated by comparing vehicle-treated and CGS or T1-11-treated NPC1-/- mice for their motor deficits (analyzed by both rotarod and footprint tests), hippocampal cognitive impairment (by Novel Object Recognition (NOR) test), cerebellar neurodegeneration (Purkinje neurons counting), and cholesterol and sphingomyelin accumulation in spleen and liver. Finally, the effect of both agonists on survival was evaluated by applying a humane late endpoint (weight loss >30% of peak weight, punched posture and reduced activity in the cage). The results demonstrated that, while CGS21680 only slightly attenuated cognitive deficits, T1-11 ameliorated motor coordination, significantly improved cognitive impairments, increased the survival of Purkinje neurons and reduced sphingomyelin accumulation in the liver. More importantly, it significantly prolonged the lifespan of NPC1-/- mice. In vitro experiments conducted in a neuronal model of NPC1 demonstrated that the ability of T1-11 to normalize cell phenotype was mediated by the selective activation of ARs and modulation of intracellular calcium levels. In conclusion, our results fully confirm the validity of ARs as a new target for NPC1 treatment. As soon as new ligands with improved pharmacokinetic characteristics (i.e. orally active, with brain bioavailability and metabolic stability) will be obtained, AR agonists could represent a breakthrough in the treatment of NPC.
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http://dx.doi.org/10.1016/j.nbd.2017.10.013DOI Listing
February 2018

Fingolimod: A Disease-Modifier Drug in a Mouse Model of Amyotrophic Lateral Sclerosis.

Neurotherapeutics 2016 10;13(4):918-927

Department of Cell Biology and Neurosciences, Istituto Superiore di Sanità, Rome, Italy.

Fingolimod phosphate (FTY720), the first approved oral therapy for multiple sclerosis, primarily acts as an immunomodulator. Its concomitant effects in the central nervous system, however, indicate a potentially broader spectrum of activity in neurodegenerative diseases. In the present study, we investigated the possible effects of fingolimod in a mouse model of amyotrophic lateral sclerosis (ALS), a neurodegenerative disease characterized by a strong neuroinflammatory component. Fingolimod (0.1 and 1 mg/kg i.p.) was administered to mSOD1 mice, a well-characterized mouse model of ALS, starting from the onset of motor symptoms to the end stage of the disease. The drug was able to improve the neurological phenotype (p < 0.05) and to extend the survival (p < 0.01) of ALS mice. The beneficial effect of fingolimod administration was associated with a significant modulation of neuroinflammatory and protective genes (CD11b, Foxp3, iNOS, Il1β, Il10, Arg1, and Bdnf) in motor cortex and spinal cord of animals. Our data show, for the first time, that fingolimod is protective in ALS mice and that its beneficial effects are accompanied by a modulation of microglial activation and innate immunity. Considering that the treatment was started in already symptomatic mice, our data strongly support fingolimod as a potential new therapeutic approach to ALS.
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http://dx.doi.org/10.1007/s13311-016-0462-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5081121PMC
October 2016

Aberrant self-grooming as early marker of motor dysfunction in a rat model of Huntington's disease.

Behav Brain Res 2016 10 30;313:53-57. Epub 2016 Jun 30.

Unit of Neurotoxicology and Neuroendocrinology, Department of Cell Biology and Neurosciences, Istituto Superiore di Sanità, Rome, Italy. Electronic address:

In the study of neurodegenerative diseases, rodent models provide experimentally accessible systems to study multiple pathogenetic aspects. The identification of early and robust behavioural changes is crucial to monitoring disease progression and testing potential therapeutic strategies in animals. Consistent experimental data support the translational value of rodent self-grooming as index of disturbed motor functions and perseverative behaviour patterns in different rodent models of brain disorders. Huntington's disease (HD) is a progressive neurodegenerative disorder, characterized by severe degeneration of basal ganglia, cognitive and psychiatric impairments and motor abnormalities. In the rat species, intrastriatal injection of the excitotoxin quinolinic acid (QA) mimics some of the neuroanatomical and behavioural changes found in HD, including the loss of GABAergic neurons and the appearance of motor and cognitive deficits. We show here that striatal damage induced by unilateral QA injection in dorsal striatum of rats triggers aberrant grooming behaviour as early as three weeks post-lesion in absence of other motor impairments: specifically, both quantitative (frequency and duration) and qualitative (the sequential pattern of movements) features of self-grooming behaviour were significantly altered in QA-lesioned rats placed in either the elevated plus-maze and the open-field. The consistent abnormalities in self-grooming recorded in two different experimental contexts support the use of this behavioural marker in rodent models of striatal damage such as HD, to assess the potential effects of drug and cell replacement therapy in the early stage of disease.
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http://dx.doi.org/10.1016/j.bbr.2016.06.058DOI Listing
October 2016

Striatal adenosine-cannabinoid receptor interactions in rats over-expressing adenosine A2A receptors.

J Neurochem 2016 Mar 24;136(5):907-17. Epub 2015 Nov 24.

Department Therapeutic Research and Medicines Evaluation, Istituto Superiore di Sanità, Rome, Italy.

Adenosine A2A receptors (A2 A Rs) and cannabinoid CB1 receptors (CB1 Rs) are highly expressed in the striatum, where they functionally interact and form A2A /CB1 heteroreceptor complexes. We investigated the effects of CB1 R stimulation in a transgenic rat strain over-expressing A2 A Rs under the control of the neural-specific enolase promoter (NSEA2A rats) and in age-matched wild-type (WT) animals. The effects of the CB1 R agonist WIN 55,212-2 (WIN) were significantly lower in NSEA2A rats than in WT animals, as demonstrated by i) electrophysiological recordings of synaptic transmission in corticostriatal slices; ii) the measurement of glutamate outflow from striatal synaptosomes and iii) in vivo experiments on locomotor activity. Moreover, while the effects of WIN were modulated by both A2 A R agonist (CGS 21680) and antagonists (ZM 241385, KW-6002 and SCH-442416) in WT animals, the A2 A R antagonists failed to influence WIN-mediated effects in NSEA2A rats. The present results demonstrate that in rats with genetic neuronal over-expression of A2 A Rs, the effects mediated by CB1 R activation in the striatum are significantly reduced, suggesting a change in the stoichiometry of A2A and CB1 receptors and providing a strategy to dissect the involvement of A2 A R forming or not forming heteromers in the modulation of striatal functions. These findings add additional evidence for the existence of an interaction between striatal A2 A Rs and CB1 Rs, playing a fundamental role in the regulation of striatal functions. We studied A2A -CB1 receptor interaction in transgenic rats over-expressing adenosine A2A receptors under the control of the neuron-specific enolase promoter (NSEA2A ). In these rats, we demonstrated a reduced effect of the CB1 receptor agonist WIN 55,212-2 in the modulation of corticostriatal synaptic transmission and locomotor activity, while CB1 receptor expression level did not change with respect to WT rats. A reduction in the expression of A2A -CB1 receptor heteromers is postulated.
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http://dx.doi.org/10.1111/jnc.13421DOI Listing
March 2016

Expression, pharmacology and functional activity of adenosine A1 receptors in genetic models of Huntington's disease.

Neurobiol Dis 2014 Nov 15;71:193-204. Epub 2014 Aug 15.

Istituto Superiore di Sanità, Department of Therapeutic Research and Medicines Evaluation, Viale Regina Elena 299, 00161 Rome, Italy.

Adenosine A1 receptor (A1R) stimulation exerts beneficial effects in response to various insults to the brain and, although it was found neuroprotective in a lesional model of Huntington's disease (HD), the features of this receptor in genetic models of HD have never been explored. In the present study we characterized the expression, affinity and functional effects of A1Rs in R6/2 mice (the most widely used transgenic model of HD) and in a cellular model of HD. Binding studies revealed that the density of A1Rs was significantly reduced in the cortex and the striatum of R6/2 mice compared to age-matched wild-type (WT), while receptor affinity was unchanged. The selective A1R agonist cyclopentyladenosine (CPA, 300nM) was significantly more effective in reducing synaptic transmission in corticostriatal slices from symptomatic R6/2 than in age-matched WT mice. Such an effect was due to a stronger inhibition of glutamate release from the pre-synaptic terminal. The different functional activities of A1Rs in HD mice were associated also to a different intracellular signaling pathway involved in the synaptic effect of CPA. In fact, while the PKA pathway was involved in both genotypes, p38 MAPK inhibitor SB203580 partially prevented synaptic effects of CPA in R6/2, but not in WT, mice; moreover, CPA differently modulated the phosphorylation status of p38 in the two genotypes. In vitro studies confirmed a different behavior of A1Rs in HD: CPA (100 nM for 5h) modulated cell viability in STHdh(Q111/Q111) (mhttHD cells), without affecting the viability of STHdh(Q7/Q7) (wthtt cells). This effect was prevented by the application of SB203580. Our results demonstrate that in the presence of the HD mutation A1Rs undergo profound changes in terms of expression, pharmacology and functional activity. These changes have to be taken in due account when considering A1Rs as a potential therapeutic target for this disease.
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http://dx.doi.org/10.1016/j.nbd.2014.08.013DOI Listing
November 2014

Spinal cord pathology is ameliorated by P2X7 antagonism in a SOD1-mutant mouse model of amyotrophic lateral sclerosis.

Dis Model Mech 2014 Sep 18;7(9):1101-9. Epub 2014 Jul 18.

Cellular Biology and Neurobiology Institute, CNR, Via del Fosso di Fiorano, 65, 00143 Rome, Italy Santa Lucia Foundation, IRCCS, Via Ardeatina, 306, 00179 Rome, Italy

In recent years there has been an increasing awareness of the role of P2X7, a receptor for extracellular ATP, in modulating physiopathological mechanisms in the central nervous system. In particular, P2X7 has been shown to be implicated in neuropsychiatry, chronic pain, neurodegeneration and neuroinflammation. Remarkably, P2X7 has also been shown to be a 'gene modifier' in amyotrophic lateral sclerosis (ALS): the receptor is upregulated in spinal cord microglia in human and rat at advanced stages of the disease; in vitro, activation of P2X7 exacerbates pro-inflammatory responses in microglia that have an ALS phenotype, as well as toxicity towards neuronal cells. Despite this detrimental in vitro role of P2X7, in SOD1-G93A mice lacking P2X7, the clinical onset of ALS was significantly accelerated and disease progression worsened, thus indicating that the receptor might have some beneficial effects, at least at certain stages of disease. In order to clarify this dual action of P2X7 in ALS pathogenesis, in the present work we used the antagonist Brilliant Blue G (BBG), a blood-brain barrier permeable and safe drug that has already been proven to reduce neuroinflammation in traumatic brain injury, cerebral ischemia-reperfusion, neuropathic pain and experimental autoimmune encephalitis. We tested BBG in the SOD1-G93A ALS mouse model at asymptomatic, pre-symptomatic and late pre-symptomatic phases of disease. BBG at late pre-onset significantly enhanced motor neuron survival and reduced microgliosis in lumbar spinal cord, modulating inflammatory markers such as NF-κB, NADPH oxidase 2, interleukin-1β, interleukin-10 and brain-derived neurotrophic factor. This was accompanied by delayed onset and improved general conditions and motor performance, in both male and female mice, although survival appeared unaffected. Our results prove the twofold role of P2X7 in the course of ALS and establish that P2X7 modulation might represent a promising therapeutic strategy by interfering with the neuroinflammatory component of the disease.
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http://dx.doi.org/10.1242/dmm.017038DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4142730PMC
September 2014

The stimulation of adenosine A2A receptors ameliorates the pathological phenotype of fibroblasts from Niemann-Pick type C patients.

J Neurosci 2013 Sep;33(39):15388-93

Department of Cell Biology and Neuroscience, and Department of Therapeutic Research and Medicines Evaluation, Istituto Superiore di Sanità, 00161 Rome, Italy.

Niemann-Pick type C1 (NPC1) disease is a rare neurovisceral disorder characterized by intracellular accumulation of unesterified cholesterol, sphingolipids, and other lipids in the lysosomal compartment. A deregulation of lysosomal calcium has been identified as one of the earliest steps of the degenerative process. Since adenosine A2A receptors (A2ARs) control lysosome trafficking and pH, which closely regulates lysosomal calcium, we hypothesized a role for these receptors in NPC1. The aim of this study was to evaluate the effects of the A2AR agonist CGS21680 on human control and NPC1 fibroblasts. We show that CGS21680 raises lysosomal calcium levels and rescues mitochondrial functionality (mitochondrial inner membrane potential and expression of the complex IV of the mitochondrial respiratory chain), which is compromised in NPC1 cells. These effects are prevented by the selective blockade of A2ARs by the antagonist ZM241385. The effects of A2AR activation on lysosomal calcium are not mediated by the cAMP/PKA pathway but they appear to involve the phosphorylation of ERK1/2. Finally, CGS21680 reduces cholesterol accumulation (Filipin III staining), which is the main criterion currently used for identification of a compound or pathway that would be beneficial for NPC disease, and such an effect is prevented by the Ca(2+) chelator BAPTA-AM. Our findings strongly support the hypothesis that A2AR agonists may represent a therapeutic option for NPC1 and provide insights on their mechanisms of action.
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http://dx.doi.org/10.1523/JNEUROSCI.0558-13.2013DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6618463PMC
September 2013

Cocaine-induced changes of synaptic transmission in the striatum are modulated by adenosine A2A receptors and involve the tyrosine phosphatase STEP.

Neuropsychopharmacology 2014 Feb 30;39(3):569-78. Epub 2013 Aug 30.

Department Therapeutic Research and Medicines Evaluation, Istituto Superiore di Sanità, Roma, Italy.

The striatum is a brain area implicated in the pharmacological action of drugs of abuse. Adenosine A2A receptors (A2ARs) are highly expressed in the striatum and mediate, at least in part, cocaine-induced psychomotor effects in vivo. Here we studied the synaptic mechanisms implicated in the pharmacological action of cocaine in the striatum and investigated the influence of A2ARs. We found that synaptic transmission was depressed in corticostriatal slices after perfusion with cocaine (10 μM). This effect was reduced by the A2AR antagonist ZM241385 and almost abolished in striatal A2AR-knockout mice (mice lacking A2ARs in striatal neurons, stA2ARKO). The effect of cocaine on synaptic transmission was also prevented by the protein tyrosine phosphatases (PTPs) inhibitor sodium orthovanadate (Na3VO4). In synaptosomes prepared from striatal slices, we found that the activity of striatal-enriched protein tyrosine phosphatase (STEP) was upregulated by cocaine, prevented by ZM241385, and absent in synaptosomes from stA2ARKO. The role played by STEP in cocaine modulation of synaptic transmission was investigated in whole-cell voltage clamp recordings from medium spiny neurons of the striatum. We found that TAT-STEP, a peptide that renders STEP enzymatically inactive, prevented cocaine-induced reduction in AMPA- and NMDA-mediated excitatory post-synaptic currents, whereas the control peptide, TAT-myc, had no effect. These results demonstrate that striatal A2ARs modulate cocaine-induced synaptic depression in the striatum and highlight the potential role of PTPs and specifically STEP in the effects of cocaine.
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http://dx.doi.org/10.1038/npp.2013.229DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3895235PMC
February 2014

A2A adenosine receptors are up-regulated in lymphocytes from amyotrophic lateral sclerosis patients.

Amyotroph Lateral Scler Frontotemporal Degener 2013 Sep 16;14(5-6):406-13. Epub 2013 May 16.

Department of Medical Sciences, Pharmacology Section, University of Ferrara, via Fossato di Mortara 17-19, Ferrara, Italy

Adenosine, a purine nucleoside interacting with A1, A2A, A2B and A3 adenosine receptors (ARs), is a potent endogenous modulator of inflammatory and neuronal processes involved in the pathophysiology of several neurodegenerative diseases. In the present study, ARs were investigated in lymphocytes from patients with amyotrophic lateral sclerosis (ALS) and compared with age-matched healthy subjects. In ALS patients A2AARs were analysed by using RT-PCR, Western blotting and saturation binding experiments. The effect of A2AAR stimulation on cyclic AMP levels was evaluated in lymphocytes from ALS patients and healthy subjects. An up-regulation of A2AARs was observed in ALS patients with respect to healthy subjects while A1, A2B and A3AR affinity and density did not change. In ALS patients, the A2AAR density values correlated with the Amyotrophic Lateral Sclerosis Functional Rating Scale-Revised (ALSFRS-R) scores. Furthermore, the stimulation of A2AARs mediated a significant increase in cyclic AMP levels in lymphocytes from ALS patients, with a higher potency than in lymphocytes from healthy subjects. In conclusion, the positive correlation between A2AAR density and ALSFRS-R scores could indicate a possible protective effect of this receptor subtype, representing an interesting starting point for the study of alternative therapeutic approaches for ALS based on A2AAR modulation.
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http://dx.doi.org/10.3109/21678421.2013.793358DOI Listing
September 2013

Prolonged lifespan with enhanced exploratory behavior in mice overexpressing the oxidized nucleoside triphosphatase hMTH1.

Aging Cell 2013 Aug 30;12(4):695-705. Epub 2013 May 30.

Department of Environment and Primary Prevention, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161 Rome, Italy.

The contribution that oxidative damage to DNA and/or RNA makes to the aging process remains undefined. In this study, we used the hMTH1-Tg mouse model to investigate how oxidative damage to nucleic acids affects aging. hMTH1-Tg mice express high levels of the hMTH1 hydrolase that degrades 8-oxodGTP and 8-oxoGTP and excludes 8-oxoguanine from both DNA and RNA. Compared to wild-type animals, hMTH1-overexpressing mice have significantly lower steady-state levels of 8-oxoguanine in both nuclear and mitochondrial DNA of several organs, including the brain. hMTH1 overexpression prevents the age-dependent accumulation of DNA 8-oxoguanine that occurs in wild-type mice. These lower levels of oxidized guanines are associated with increased longevity and hMTH1-Tg animals live significantly longer than their wild-type littermates. Neither lipid oxidation nor overall antioxidant status is significantly affected by hMTH1 overexpression. At the cellular level, neurospheres derived from adult hMTH1-Tg neural progenitor cells display increased proliferative capacity and primary fibroblasts from hMTH1-Tg embryos do not undergo overt senescence in vitro. The significantly lower levels of oxidized DNA/RNA in transgenic animals are associated with behavioral changes. These mice show reduced anxiety and enhanced investigation of environmental and social cues. Longevity conferred by overexpression of a single nucleotide hydrolase in hMTH1-Tg animals is an example of lifespan extension associated with healthy aging. It provides a link between aging and oxidative damage to nucleic acids.
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http://dx.doi.org/10.1111/acel.12094DOI Listing
August 2013

BDNF prevents NMDA-induced toxicity in models of Huntington's disease: the effects are genotype specific and adenosine A2A receptor is involved.

J Neurochem 2013 Apr 27;125(2):225-35. Epub 2013 Feb 27.

Section of Central Nervous System Pharmacology, Department of Therapeutic Research and Medicines Evaluation, Istituto Superiore di Sanità, Rome, Italy.

NMDA receptor-mediated excitotoxicity is thought to play a pivotal role in the pathogenesis of Huntington's disease (HD). The neurotrophin brain-derived neurotrophic factor (BDNF), which is also highly involved in HD and whose effects are modulated by adenosine A2 ARs, influences the activity and expression of striatal NMDA receptors. In electrophysiology experiments, we investigated the role of BDNF toward NMDA-induced effects in HD models, and the possible involvement of A2ARs. In corticostriatal slices from wild-type mice and age-matched symptomatic R6/2 mice (a model of HD), NMDA application (75 μM) induced a transient or a permanent (i.e., toxic) reduction of field potential amplitude, respectively. BDNF (10 ng/mL) potentiated NMDA effects in wild-type, while it protected from NMDA toxicity in R6/2 mice. Both effects of BDNF were prevented by A2 AR blockade. The protective effect of BDNF against NMDA-induced toxicity was reproduced in a cellular model of HD. These findings may have very important implications for the neuroprotective potential of BDNF and A2 AR ligands in HD.
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http://dx.doi.org/10.1111/jnc.12177DOI Listing
April 2013

Effects of chronic caffeine intake in a mouse model of amyotrophic lateral sclerosis.

J Neurosci Res 2013 Apr 30;91(4):585-92. Epub 2013 Jan 30.

Department of Therapeutic Research and Medicines Evaluation, Istituto Superiore di Sanità, Rome, Italy.

Caffeine is a nonselective adenosine receptor antagonist; chronic consumption has proved protective toward neurodegenerative diseases such as Parkinson's and Alzheimer's diseases. The present study was designed to determine whether caffeine intake affected survival and/or motor performance in a transgenic model of amyotrophic lateral sclerosis (ALS). SOD1(G93A) mice received caffeine through drinking water from 70 days of age until death. Body weight, motor performance and survival were evaluated. Furthermore, the expression of adenosine A(2A) receptors (A(2A) Rs), glial glutamate transporter (GLT1), and glial fibrillar acidic protein (GFAP) were evaluated by Western blotting. The results showed that caffeine intake significantly shortened the survival of SOD1(G93A) mice (log rank test, P = 0.01) and induced a nonsignificant advancing of disease onset. The expression of A(2A) R, GLT1, and GFAP was altered in the spinal cords of ALS mice, but caffeine did not influence their expression in either wild-type or SOD1(G93) mice. These data indicate that adenosine receptors may play an important role in ALS.
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http://dx.doi.org/10.1002/jnr.23185DOI Listing
April 2013

NMDA receptor dysfunction contributes to impaired brain-derived neurotrophic factor-induced facilitation of hippocampal synaptic transmission in a Tau transgenic model.

Aging Cell 2013 Feb 23;12(1):11-23. Epub 2012 Nov 23.

Université Lille-Nord de France, UDSL, F-59045, Lille Cedex, France.

While the spatiotemporal development of Tau pathology has been correlated with occurrence of cognitive deficits in Alzheimer's patients, mechanisms underlying these deficits remain unclear. Both brain-derived neurotrophic factor (BDNF) and its tyrosine kinase receptor TrkB play a critical role in hippocampus-dependent synaptic plasticity and memory. When applied on hippocampal slices, BDNF is able to enhance AMPA receptor-dependent hippocampal basal synaptic transmission through a mechanism involving TrkB and N-methyl-d-Aspartate receptors (NMDAR). Using THY-Tau22 transgenic mice, we demonstrated that hippocampal Tau pathology is associated with loss of synaptic enhancement normally induced by exogenous BDNF. This defective response was concomitant to significant memory impairments. We show here that loss of BDNF response was due to impaired NMDAR function. Indeed, we observed a significant reduction of NMDA-induced field excitatory postsynaptic potential depression in the hippocampus of Tau mice together with a reduced phosphorylation of NR2B at the Y1472, known to be critical for NMDAR function. Interestingly, we found that both NR2B and Src, one of the NR2B main kinases, interact with Tau and are mislocalized to the insoluble protein fraction rich in pathological Tau species. Defective response to BDNF was thus likely related to abnormal interaction of Src and NR2B with Tau in THY-Tau22 animals. These are the first data demonstrating a relationship between Tau pathology and synaptic effects of BDNF and supporting a contribution of defective BDNF response and impaired NMDAR function to the cognitive deficits associated with Tauopathies.
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http://dx.doi.org/10.1111/acel.12018DOI Listing
February 2013

Potential therapeutic relevance of adenosine A2B and A2A receptors in the central nervous system.

CNS Neurol Disord Drug Targets 2012 Sep;11(6):664-74

Department of Therapeutic Research and Medicines Evaluation, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161 Roma, Italy.

Adenosine A2B and, much more importantly, adenosine A2A receptors modulate many physiological and pathological processes in the brain. In this review, the most recent evidence concerning the role of such receptors and their potential therapeutic relevance is discussed. The low affinity of A2B receptors for adenosine implies that they might represent a good therapeutic target, since they are activated only under pathological conditions (when adenosine levels raise up to micromolar concentrations). The availability of selective ligands for A2B receptors would allow exploration of such an hypothesis. Since adenosine A2A receptors mediate both potentially neuroprotective and potentially neurotoxic effects, their role in neurodegenerative diseases is highly controversial. Nevertheless, A2A receptor antagonists have shown clear antiparkinsonian effects, and a great interest exists on the role of A2A receptors in Alzheimer's disease, brain ischaemia, spinal cord injury, drug addiction and other conditions. In order to establish whether such receptors represent a target for CNS diseases, at least two conditions are needed: the full comprehension of A2A-dependent mechanisms and the availability of ligands capable of discriminating among the different receptor populations.
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http://dx.doi.org/10.2174/187152712803581100DOI Listing
September 2012

Adenosine A(2A)-cannabinoid CB(1) receptor interaction: an integrative mechanism in striatal glutamatergic neurotransmission.

Brain Res 2012 Oct 4;1476:108-18. Epub 2012 May 4.

Section of Central Nervous System Pharmacology, Department of Therapeutic Research and Medicines Evaluation, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161 Rome, Italy.

The striatum is a subcortical area involved in sensorimotor, cognitive and emotional processes. Adenosine A(2A) receptors (A(2A)Rs) are highly expressed in the striatum, and their ability to establish functional and molecular interactions with many other receptors attributes to a pivotal role in the modulation and integration of striatal neurotransmission. This review will focus on the interaction between A(2A)Rs and cannabinoid CB(1) receptors (CB(1)Rs), taking it as a paradigmatic example of synaptic integration. Indeed, A(2A)Rs can exert an opposite (permissive vs. inhibitory) influence on CB1-dependent synaptic effect. These apparently irreconcilable functions could depend on a different role of pre- vs. postsynaptic A(2A)Rs, on their interaction with other receptors (namely adenosine A(1), metabotropic glutamate 5 and dopamine D2 receptors), and on whether A(2A)Rs form or not heteromers with CB(1)Rs. Besides providing a good example of the intricate pattern of events taking place in striatal synapses, the A(2A)/CB(1)R interaction proves very informative to understand the physiology of the basal ganglia and the mechanisms of related diseases. This article is part of a Special Issue entitled: Brain Integration.
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http://dx.doi.org/10.1016/j.brainres.2012.04.051DOI Listing
October 2012

Unbalance of CB1 receptors expressed in GABAergic and glutamatergic neurons in a transgenic mouse model of Huntington's disease.

Neurobiol Dis 2012 Mar 23;45(3):983-91. Epub 2011 Dec 23.

Department of Therapeutic Research and Medicine Evaluation, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161 Rome, Italy.

Cannabinoid CB1 receptors (CB1Rs) are known to be downregulated in patients and in animal models of Huntington's disease (HD). However, the functional meaning of this reduction, if any, is still unclear. Here, the effects of the cannabinoid receptor agonist WIN 55,212-2 (WIN) were investigated on striatal synaptic transmission and on glutamate and GABA release in symptomatic R6/2 mice, a genetic model of HD. The expression levels of CB1Rs in glutamatergic and GABAergic synapses were also evaluated. We found that in R6/2 mice, WIN effects on synaptic transmission and glutamate release were significantly increased with respect to wild type mice. On the contrary, a decrease in WIN-induced reduction of GABA release was found in R6/2 versus WT mice. The expression of CB1Rs in GABAergic neurons was drastically reduced, while CB1Rs levels in glutamatergic neurons were unchanged. These results demonstrate that the expression and functionality of CB1Rs are differentially affected in GABAergic and glutamatergic neurons in R6/2 mice. As a result, the balance between CB1Rs expressed by the two neuronal populations and, thus, the net effect of CB1R stimulation, is profoundly altered in HD mice.
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http://dx.doi.org/10.1016/j.nbd.2011.12.017DOI Listing
March 2012

Complex behavioral and synaptic effects of dietary branched chain amino acids in a mouse model of amyotrophic lateral sclerosis.

Mol Nutr Food Res 2011 Apr 5;55(4):541-52. Epub 2011 Jan 5.

Section of Neurotoxicology and Neuroendocrinology, Department of Cell Biology and Neurosciences, Istituto Superiore di Sanità, Rome, Italy.

Scope: We hypothesized that chronic supplementation with branched chain amino acids (BCAAs) affects neurobehavioral development in vulnerable gene backgrounds.

Methods And Results: A murine model of amyotrophic lateral sclerosis (ALS), G93A mice bearing the mutated human superoxide dismutase 1 (SOD1) gene, and control mice received from 4 to 16 wk of age dietary supplementation with BCAAs at doses comparable to human usage. Motor coordination, exploratory behaviors, pain threshold, synaptic activity and response to glutamatergic stimulation in primary motor cortex slices were evaluated between the 8th and 16th week. The glial glutamate transporter 1 (GLT-1) and metabotropic glutamate 5 receptor (mGlu5R) were analyzed by immunoblotting in cortex, hippocampus and striatum. BCAAs induced hyperactivity, decreased pain threshold in wild-type mice and exacerbated the motor deficits of G93A mice while counteracting their abnormal pain response. Electrophysiology on G93A brain slices showed impaired synaptic function, reduced toxicity of GLT-1 blocking and increased glutamate toxicity prevented by BCAAs. Immunoblotting indicated down-regulation of GLT-1 and mGlu5R in G93A, both effects counteracted by BCAAs.

Conclusion: These results, though not fully confirming a role of BCAAs in ALS-like etiology in the genetic model, clearly indicate that BCAAs' complex effects on central nervous system depend on gene background and raise alert over their spread use.
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http://dx.doi.org/10.1002/mnfr.201000296DOI Listing
April 2011

The role of the Istituto Superiore di Sanità as the competent authority for Phase I trials in the translation of advanced therapies.

Ann Ist Super Sanita 2011 ;47(1):79-82

Secretariat of the Commitee for the Evaluation of Phase I Clinical Trials, Dipartimento del Farmaco, Istituto Superiore di Sanità, Rome, Italy.

Advanced therapy medicinal products (ATMP) can offer new, effective therapeutic options for the treatment of severe illnesses, including cancer, neurodegenerative and cardiovascular diseases. Translation of advanced therapies to the clinic has been slow despite significant academic research from academia and foundations. The implementation of 2001/20 Directive in Italy established that the development of an ATMP should follow the GXP rules - good manufacturing practice (GMP) for production, good laboratory practice (GLP) for non clinical safety studies and good clinical practice (GCP) for clinical trials. The high costs of GCP application and the needs for GMP facilities are perceived as the most important bottlenecks for the development of ATMP. Here it is pointed out that a strategic cooperation between different actors (academia, industry and experts in regulatory issues) is strongly needed. In particular, it is highlighted that the Istituto Superiore di Sanità, as the competent authority for the authorization of Phase I clinical trials, has a specific responsibility in fostering the translation of safe and effective therapies for human diseases.
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http://dx.doi.org/10.4415/ANN_11_01_16DOI Listing
July 2011

New challenges in translational medicine: transforming the advancement of science into cures. Preface.

Ann Ist Super Sanita 2011 ;47(1):5-7

Istituto Superiore di Sanità, Rome, Italy.

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http://dx.doi.org/10.4415/ANN_11_01_02DOI Listing
July 2011