Gabriella Marcon

Mutant Prion Protein Expression Causes Motor and Memory Deficits and Abnormal Sleep Patterns in a Transgenic Mouse Model

A familial form of Creutzfeldt-Jakob disease (CJD) is linked to the D178N/V129 prion protein (PrP) mutation. Tg(CJD) mice expressing the mouse homolog of this mutant PrP synthesize a misfolded form of the mutant protein, which is aggregated and protease resistant. These mice develop clinical and pathological features reminiscent of CJD, including motor dysfunction, memory impairment, cerebral PrP deposition, and gliosis. Tg(CJD) mice also display electroencephalographic abnormalities and severe alterations of sleep-wake patterns strikingly similar to those seen in a human patient carrying the D178N/V129 mutation. Neurons in these mice show swelling of the endoplasmic reticulum (ER) with intracellular retention of mutant PrP, suggesting that ER dysfunction could contribute to the pathology. These results establish a transgenic animal model of a genetic prion disease recapitulating cognitive, motor, and neurophysiological abnormalities of the human disorder. Tg(CJD) mice have the potential for giving greater insight into the spectrum of neuronal dysfunction in prion diseases.

Doxycycline in Creutzfeldt-Jakob disease: a phase 2, randomised, double-blind, placebo-controlled trial.

BACKGROUND Creutzfeldt-Jakob disease (CJD) is a fatal, untreatable prion encephalopathy. Previous studies showed that doxycycline is effective in in-vitro and in-vivo models of disease, and patients with CJD who received compassionate treatment with doxycycline showed increased survival time compared with historical series. We therefore did a randomised, double-blind study of doxycycline versus placebo in CJD. METHODS We recruited patients older than 18 years old who had a diagnosis of definite or probable sporadic CJD or genetic forms of the disease via Italian reference centres and the French national referral system. Patients were randomly assigned (ratio 1:1) to receive oral doxycycline (100 mg daily) or placebo under double-blind conditions from the day of randomisation to death. Centralised randomisation was done independently of enrolment or evaluation of patients using a minimisation method in Italy and a simple randomisation in France. Participants, caregivers, and clinicians were masked to group assignment. The primary efficacy variable was the survival time from randomisation. Interim analyses were planned to detect a significant effect of treatment as early as possible. This trial is registered with EudraCT, 2006-001858-27 for the Italian study and 2007-005553-34 for the French study. FINDINGS From April 12, 2007, to Aug 19, 2010, in Italy, and from Jan 30, 2009, to Jan 10, 2012, in France, 121 patients with CJD were enrolled in the study, 62 of whom were randomly assigned to the treatment group and 59 to the placebo group. The first interim analysis showed absence of superiority of doxycycline compared with placebo, and the trial was stopped for futility. Efficacy analyses did not show significant differences between patients treated with doxycycline and placebo with regard to survival times (HR 1.1, 95% CI 0.8-1.7, p=0.50). Serious adverse events were judged not to be related to treatment, whereas a relation was deemed probable or possible for five non-serious adverse events that occurred in each treatment group. INTERPRETATION Doxycycline at a dose of 100 mg per day was well tolerated but did not significantly affect the course of CJD, at variance with the results of previous observational studies. Our experience could be useful in the design of large multinational controlled trials of potential anti-prion molecules in this rare disease. FUNDING Agenzia Italiana Farmaco, Italian Ministry of Health, AIEnP, and French Ministry of Health.

Association between 5-HT2A receptor polymorphism and psychotic symptoms in Alzheimer’s disease

Abstract Background: The aim of this study is to analyze the segregation of the 102T/C polymorphism in the serotonin 2A receptor gene in patients affected by sporadic and familial Alzheimer’s disease (FAD) with and without psychotic symptoms. Methods: The polymorphism was analyzed in 275 subjects. A semistructured interview was used to obtain information about delusions, hallucinations, and other specific behavioral signs occurring during the disease. Results: Fifty-two percent of AD patients with psychotic symptoms were homozygous for the C102 allele, as compared with 6.9% of AD patients without psychosis. Similarly, the C102/C102 genotype was significantly more frequent in FAD patients with psychosis than in FAD patients without (46.5% vs. 7.8%). Conclusions: Our data strongly confirm and extend to FAD previous studies suggesting that the genetic variation at this locus is associated with prominent psychotic features in AD and that the 102C allele could play an important role in late-onset AD.

A novel PSEN2 mutation associated with a peculiar phenotype.

Background: Mutations of presenilin 2 gene are a rare cause of familial Alzheimer disease (AD). We describe an Italian family with hereditary dementia associated with a novel mutation in the presenilin 2 gene. Methods: Clinical investigations of the diseased subjects; interviews with relatives; studies of medical records; pedigree analysis; and neuroradiologic, neuropathologic, and molecular genetic studies were carried out in the pedigree. Results: Genetic analysis showed a novel PSEN2 A85V mutation present in the proband and in all analyzed affected members, in a subject presenting with an amnesic mild cognitive impairment, and in a young, still asymptomatic subject. The proband showed a clinical phenotype indicative of Lewy body dementia and the neuropathologic examination demonstrated the presence of unusually abundant and widespread cortical Lewy bodies in addition to the hallmark lesions of AD. Other affected members exhibited a clinical phenotype typical of AD. Conclusions: Our findings add complexity to the spectrum of atypical phenotypes associated with presenilin mutations and should then be taken into account when considering the nosography of neurodegenerative diseases. They also support previous data that specific mutations of genes associated with familial Alzheimer disease may influence the presence and extent of Lewy bodies.

APE1/Ref-1 regulates PTEN expression mediated by Egr-1

APE1/Ref-1, the mammalian ortholog of E. coli Xth, and a multifunctional protein possessing both DNA repair and transcriptional regulatory activities, has dual role in controlling cellular response to oxidative stress. It is rate-limiting in repair of oxidative DNA damage including strand breaks and also has co-transcriptional activity by modulating genes expression directly regulated by Egr-1 and p53 transcription factors. PTEN, a phosphoinositide phosphatase, acts as an ‘off’ switch in the PI-3 kinase/Akt signalling pathway and regulates cell growth and survival. It is shown here that transient alteration in the APE1 level in HeLa cells modulates PTEN expression and that acetylatable APE1 is required for the activation of the PTEN gene. Acetylation of APE1 enhances its binding to distinct trans-acting complexes involved in activation or repression. The acetylated protein is deacetylated in vivo by histone deacetylases. It was found that exposure of HeLa cells to H2O2 and to histone deacetylase inhibitors increases acetylation of APE1 and induction of PTEN. The absence of such induction in APE1-downregulated HeLa cells confirmed APE1s role in regulating inducible PTEN expression. That APE1-dependent PTEN expression is mediated by Egr-1 was supported by experiments with cells ectopically expressing Egr-1. Thus, the data open new perspectives in the comprehension of the many functions exerted by APE1 in controlling cell response to oxidative stress.

Hereditary cerebral hemorrhage with amyloidosis associated with the E693K mutation of APP.

OBJECTIVE To report the clinical, genetic, neuroimaging, and neuropathologic studies of patients with the hereditary cerebral hemorrhage with amyloidosis linked to the APP E693K mutation. DESIGN Case series. Clinical details and laboratory results were collected by direct evaluation and previous medical records. DNA analysis was carried out in several affected subjects and healthy individuals. Neuropathologic examination was performed in 2 subjects. SETTING Southern Lombardy, Italy. Patients Individuals with and without amyloidosis in 4 unrelated Italian families (N = 37). Main Outcome Measure Genotype-phenotype relationship. RESULTS The affected individuals presented with recurrent headache and multiple strokes, followed by epilepsy and cognitive decline in most of them. The disease was inherited with an autosomal dominant trait and segregated with the APP E693K mutation. Neuroimaging demonstrated small to large hematomas, subarachnoid bleeding, scars with hemosiderin deposits, small infarcts, and leukoaraiosis. Amyloid-beta immunoreactivity was detected in the wall of leptomeningeal and parenchymal vessels and in the neuropil, whereas phosphorylated tau, neurofibrillary changes, and neuritic plaques were absent. CONCLUSIONS These findings expand the number of APP mutations linked to hereditary cerebral hemorrhage with amyloidosis, reinforcing the link between this phenotype and codon 693 of APP.

Guidelines for the diagnosis of dementia and Alzheimer's disease

SIN DOCUMENT*The Dementia Study Group is co-ordinated by Sandro Sorbi andincludes: Margherita Alberoni, Milan; Pasquale Alfieri, SommaVesuviana (NA); Serena Amici, Perugia; Daniele Antana, Rome;Ildebrando Appollonio, Monza (MI); Stefano Avanzi,Castelgoffredo (MN); Antonella Bartoli, Pescara; BrunoBergamasco, Turin; Laura Bracco, Florence; Amalia Bruni,Lamezia Terme (CZ); Orso Bugiani, Milan; Paolo Caffarra, Parma;Carlo Caltagirone, Rome; Antonio Carolei, L’Aquila; Anna RosaCasini, Rome; Luciana Ciannella, Benevento; Antonietta Citterio,Pavia; Antonio Daniele, Rome; Graziella D’Achille, Isernia;Giuseppe Del Curatolo, Grosseto; Grazia Dell’Agnello, Pisa;Daniele Durante, Parma; Elisabetta Farina, Milan; Patrizia Ferrero,Turin; Paolo Forleo, Florence; Guido Gainotti, Rome; PaoloGabriele, Cassino (FR); Emanuela Galante, Castelgoffredo (MN);Virgilio Gallai, Perugia; Roberto Gallassi, Bologna; MaddalenaGasparini, Milan; Bernardino Ghetti, Indianapolis (USA); GiorgioGiaccone, Milan; Floriano Girotti, Milan; Luigi Grimaldi, Milanand Caltanisetta; Serenella Grioli, Catania; Bianca MariaGuarnieri, Pescara; Stefano Grottoli, Fossombrone (PS); FrancescoIemolo, Ragusa; Stefania Latorraca, Florence; Francesco Le Pira,Catania; Gian Luigi Lenzi, Rome; Sebastiano Lorusso, Rimini;Claudio Mariani, Milan; Gabriella Marcon, Udine; VincenzoMascia, Carbonia (CA); Simonetta Mearelli, L’Aquila; MariaMorante, Senigallia (AN); Michela Morbin, Milan; MassimoMusicco, Segrate (MI); Ettore Nardelli, Verona; Paolo Nichelli,Modena; Alessandro Padovani, Brescia; Marco Paganini, Florence;Roberta Pantieri, Bologna; Pietro Parisen, Vicenza; LucillaParnetti, Perugia; Bruno Passerella, Brindisi; Carla Pettenati, Rho(MI); Silvia Piacentini, Florence; Federico Piccoli, Palermo; CarloPiccolini, Perugia; Gilberto Pizzolato, Padova; LeandroProvinciali, Ancona; Nicola Pugliese, Salerno; Francesco Redi,Arezzo; Rosa Maria Ruggieri, Palermo; Umberto Ruggiero,Naples; Marco Saetta, Siracusa; Rudolf Schoenuber, Bolzano;Maria Caterina Silveri, Rome; Sandro Sorbi, Florence; GiuseppeSorrentino, Naples; Patrizia Sucapane, L’Aquila; Andrea Stracciari,Bologna; Massimo Tabaton, Genova; Fabrizio Tagliavini, Milan;Vito Toso, Vicenza; Francesco Valluzzi, Putignano Noci (BA)S. Sorbi ( )Department of Neurological and Psychiatric SciencesUniversity of FlorenceViale Morgagni 85, I-50131 Florence, Italy

HLA A2 allele is associated with age at onset of Alzheimer's disease.

The prevalence of the HLA A2 allele was investigated in a group of Italian patients with sporadic and early‐onset familial Alzheimers disease (AD and FAD) to analyze the potential association of this allele with early age of onset of the disease. The possible interaction between the HLA A2 allele and apolipoprotein E ε4 allele was analyzed. Our data suggest that A2 and ε4 alleles may have additive effects on AD onset, and that A2 may play an important role in determining or contributing to a very early age at onset. These findings further support the hypothesis of the involvement of an immune/inflammatory mechanism in the pathogenesis of AD. Ann Neurol 1999;45:397–400

Mental disorders associated with benzodiazepine use among older primary care attenders: A regional survey

BackgroundBenzodiazepines (BDZs) are among the most commonly prescribed drugs in the elderly and their use is often too prolonged according to current international guidelines.MethodsWe investigated the pattern of use of BDZs among 65- to 84-year-old attenders at 40 Italian primary care practices who answered positively in a questionnaire on the use of anxiolytic/hypnotic drugs and successfully completed the PRIME-MD questionnaire. The survey lasted 6 months, from February to July 2001.ResultsOf the 1,156 subjects who completed the PRIME-MD, 748 subjects were positive for at least one psychiatric diagnosis. A depressive disorder was present in 36.5% of all PRIME-MD completers and in about one-third of cases represented by major depression, whereas anxiety disorders, somatoform disorders and alcohol abuse accounted for 18.2%, 8.1% and 1.7% of all PRIME-MD completers, respectively. Most patients were first prescribed BDZs by their General Practitioners (GPs) for each diagnostic group. However, patients with pure anxiety started BDZ treatment during hospitalisation more often (19.7%) than patients with depressive disorders (13.7 %). Moreover, patients with comorbid anxiety and depressive disorders (CADD) were most likely to receive their first BDZ prescription from a psychiatrist (15.7 %). Sleep disturbances were present in at least 50% of cases (and up to 86 %) in each diagnostic group. About 75% of prescriptions concerned anxiolytic BDZ or medium/long-acting BDZ. Most patients with anxiety, CADD and depression used night-time BDZ (65.2%, 56.9 % and 60.5%, respectively). The prevalence of chronic use of BDZs was equally high in all categories of psychiatric disorder (about 90 % for each), showing that the vast majority of patients, irrespective of the diagnosis, had been using BDZs for years.ConclusionsBDZs are widely prescribed for elderly people by their GPs, often for a considerable length of time. The evidence that many BDZ consumers suffer from a depressive or an anxiety disorder, or both, could be a starting point for encouraging a rational prescription in accordance with international guidelines.

Tetracyclines and prion infectivity.

In the last decade information has accumulated on the potential anti-prion activity of polycyclic compounds. Initially we showed that the antitumoral idodoxorubicin reduced the infectivity in experimental scrapie. On the basis of the chemical homology with anthracyclines, we rapidly moved to tetracyclines, compounds that are safer and widely used as antibiotics in clinical practice. The tetracyclines, essentially doxycycline and minocycline, were characterized as a therapeutical tool in transmissible spongiform encephalopathies (TSE) through the cell-free condition, in cellular and animal models and they are now being investigated clinically with this indication. Tetracyclines interact with aggregates obtained by synthetic PrP peptides or pathological PrP (PrPsc) extracted from TSE brains, and they destabilize the structure of amyloid fibrils, reducing their resistance to digestion by proteinase K. Tetracyclines also interact with peptide oligomeric structures and inhibit the protein misfolding associated with PrPsc formation. These activities have been accompanied by a reduction of infectivity, verified by doxycycline treatment in experimental scrapie, and some curative effects after either peripheral or intracerebral infection. The anti-amyloidogenic activity of tetracyclines was tested in other forms of peripheral and central amyloidosis, with interesting results. This article analyzes the development of tetracyclines as a therapeutic tool in TSE in the light of recent results obtained in our laboratories.