Latest PUBLICATIONS

  • Lysine-specific demethylase LSD1 regulates autophagy in neuroblastoma through SESN2-dependent pathway.
    Publication Date: 07/08/2017, on Oncogene
    by Ambrosio S, Saccà CD, Amente S, Paladino S, Lania L, Majello B
    DOI: 10.1038/onc.2017.267

    Autophagy is a physiological process, important for recycling of macromolecules and maintenance of cellular homeostasis. Defective autophagy is associated with tumorigenesis and has a causative role in chemotherapy resistance in leukemia and in solid cancers. Here, we report that autophagy is regulated by the lysine-specific demethylase LSD1/KDM1A, an epigenetic marker whose overexpression is a feature of malignant neoplasia with an instrumental role in cancer development. In the present study, we determine that two different LSD1 inhibitors (TCP and SP2509) as well as selective ablation of LSD1 expression promote autophagy in neuroblastoma cells. At a mechanistic level, we show that LSD1 binds to the promoter region of Sestrin2 (SESN2), a critical regulator of mTORC1 activity. Pharmacological inhibition of LSD1 triggers SESN2 expression that hampers mTORC1 activity, leading to enhanced autophagy. SESN2 overexpression suffices to promote autophagy in neuroblastoma cells, while loss of SESN2 expression reduces autophagy induced by LSD1 inhibition. Our findings elucidate a mechanism whereby LSD1 controls autophagy in neuroblastoma cells through SESN2 transcription regulation, and we suggest that pharmacological targeting of LSD1 may have effective therapeutic relevance in the control of autophagy in neuroblastoma.Oncogene advance online publication, 7 August 2017; doi:10.1038/onc.2017.267.

  • High mobility group A1 protein modulates autophagy in cancer cells.
    Publication Date: 04/08/2017, on Cell death and differentiation
    by Conte A, Paladino S, Bianco G, Fasano D, Gerlini R, Tornincasa M, Renna M, Fusco A, Tramontano D, Pierantoni GM
    DOI: 10.1038/cdd.2017.117

    High Mobility Group A1 (HMGA1) is an architectural chromatin protein whose overexpression is a feature of malignant neoplasias with a causal role in cancer initiation and progression. HMGA1 promotes tumor growth by several mechanisms, including increase of cell proliferation and survival, impairment of DNA repair and induction of chromosome instability. Autophagy is a self-degradative process that, by providing energy sources and removing damaged organelles and misfolded proteins, allows cell survival under stress conditions. On the other hand, hyper-activated autophagy can lead to non-apoptotic programmed cell death. Autophagy deregulation is a common feature of cancer cells in which has a complex role, showing either an oncogenic or tumor suppressor activity, depending on cellular context and tumor stage. Here, we report that depletion of HMGA1 perturbs autophagy by different mechanisms. HMGA1-knockdown increases autophagosome formation by constraining the activity of the mTOR pathway, a major regulator of autophagy, and transcriptionally upregulating the autophagy-initiating kinase Unc-51-like kinase 1 (ULK1). Consistently, functional experiments demonstrate that HMGA1 binds ULK1 promoter region and negatively regulates its transcription. On the other hand, the increase in autophagosomes is not associated to a proportionate increase in their maturation. Overall, the effects of HMGA1 depletion on autophagy are associated to a decrease in cell proliferation and ultimately impact on cancer cells viability. Importantly, silencing of ULK1 prevents the effects of HMGA1-knockdown on cellular proliferation, viability and autophagic activity, highlighting how these effects are, at least in part, mediated by ULK1. Interestingly, this phenomenon is not restricted to skin cancer cells, as similar results have been observed also in HeLa cells silenced for HMGA1. Taken together, these results clearly indicate HMGA1 as a key regulator of the autophagic pathway in cancer cells, thus suggesting a novel mechanism through which HMGA1 can contribute to cancer progression.Cell Death and Differentiation advance online publication, 4 August 2017; doi:10.1038/cdd.2017.117.

  • Sativex in resistant multiple sclerosis spasticity: Discontinuation study in a large population of Italian patients (SA.FE. study).
    Publication Date: 01/08/2017, on PloS one
    by Messina S, Solaro C, Righini I, Bergamaschi R, Bonavita S, Bossio RB, Brescia Morra V, Costantino G, Cavalla P, Centonze D, Comi G, Cottone S, Danni MC, Francia A, Gajofatto A, Gasperini C, Zaffaroni M, Petrucci L, Signoriello E, Maniscalco GT, Spinicci G, Matta M, Mirabella M, Pedà G, Castelli L, Rovaris M, Sessa E, Spitaleri D, Paolicelli D, Granata A, Zappia M, Patti F,
    DOI: 10.1371/journal.pone.0180651

    The approval of Sativex for the management of multiple sclerosis (MS) spasticity opened a new opportunity to many patients. In Italy, the healthcare payer can be fully reimbursed by the involved pharma company with the cost of treatment for patients not responding after a 4 week (28 days) trial period (Payment by Results, PbR), and 50% reimbursed with the cost of 6 weeks (42 days) treatment for other patients discontinuing (Cost Sharing, CS). The aim of our study was to describe the Sativex discontinuation profile from a large population of spasticity treated Italian MS patients.

  • Coping strategies and psychological distress in caregivers of patients with Amyotrophic Lateral Sclerosis (ALS).
    Publication Date: 01/08/2017, on Amyotrophic lateral sclerosis & frontotemporal degeneration
    by Siciliano M, Santangelo G, Trojsi F, Di Somma C, Patrone M, Femiano C, Monsurrò MR, Trojano L, Tedeschi G
    DOI: 10.1080/21678421.2017.1285316

    Amyotrophic lateral sclerosis (ALS) causes distress in caregivers. The present study aims to examine the association between coping strategies and psychological distress in caregivers of ALS patients.

  • γ-COPI mediates the retention of kAE1 G701D protein in Golgi apparatus - a mechanistic explanation of distal renal tubular acidosis associated with the G701D mutation.
    Publication Date: 17/07/2017, on The Biochemical journal
    by Duangtum N, Junking M, Phadngam S, Sawasdee N, Castiglioni A, Charngkaew K, Limjindaporn T, Isidoro C, Yenchitsomanus PT
    DOI: 10.1042/BCJ20170088

    Mutations of the solute carrier family 4 member 1 (SLC4A1) gene encoding kidney anion (chloride/bicarbonate ion) exchanger 1 (kAE1) can cause genetic distal renal tubular acidosis (dRTA). Different SLC4A1 mutations give rise to mutant kAE1 proteins with distinct defects in protein trafficking. The mutant kAE1 protein may be retained in endoplasmic reticulum (ER) or Golgi apparatus, or mis-targeted to the apical membrane, failing to display its function at the baso-lateral membrane. The ER-retained mutant kAE1 interacts with calnexin chaperone protein; disruption of this interaction permits the mutant kAE1 to reach the cell surface and display anion exchange activity. However, the mechanism of Golgi retention of mutant kAE1 G701D protein, which is otherwise functional, is still unclear. In the present study, we show that Golgi retention of kAE1 G701D is due to a stable interaction with the Golgi-resident protein, coat protein complex I (COPI), that plays a role in retrograde vesicular trafficking and Golgi-based quality control. The interaction and co-localization of kAE1 G701D with the γ-COPI subunit were demonstrated in human embryonic kidney (HEK-293T) cells by co-immunoprecipitation and immunofluorescence staining. Small interference RNA (siRNA) silencing of COPI expression in the transfected HEK-293T cells increased the cell surface expression of transgenic kAE1 G701D, as shown by immunofluorescence staining. Our data unveil the molecular mechanism of Golgi retention of kAE1 G701D and suggest that disruption of the COPI-kAE1 G701D interaction could be a therapeutic strategy to treat dRTA caused by this mutant.

  • Prevalence of macular abnormalities assessed by optical coherence tomography in patients with Usher syndrome.
    Publication Date: 13/07/2017, on Ophthalmic genetics
    by Testa F, Melillo P, Rossi S, Marcelli V, de Benedictis A, Colucci R, Gallo B, Brunetti-Pierri R, Donati S, Azzolini C, Marciano E, Simonelli F
    DOI: 10.1080/13816810.2017.1329445

    To investigate the prevalence of macular abnormalities in patients affected by Usher syndrome (USH), by comparing the clinical findings between two types (i.e., USH1 and USH2).

  • Ergothioneine products derived by superoxide oxidation in endothelial cells exposed to high-glucose.
    Publication Date: 01/07/2017, on Free radical biology & medicine
    by Servillo L, D'Onofrio N, Casale R, Cautela D, Giovane A, Castaldo D, Balestrieri ML
    DOI: 10.1016/j.freeradbiomed.2017.03.009

    Ergothioneine (Egt), 2-mercapto-L-histidine betaine (ESH), is a dietary component acting as antioxidant and cytoprotectant. In vitro studies demonstrated that Egt, a powerful scavenger of hydroxyl radicals, superoxide anion, hypochlorous acid and peroxynitrite, protects vascular function against oxidative damages, thus preventing endothelial dysfunction. In order to delve the peculiar oxidative behavior of Egt, firstly identified in cell free-systems, experiments were designed to identify the Egt oxidation products when endothelial cells (EC) benefit of its protection against high-glucose (hGluc). HPLC-ESI-MS/MS analyses revealed a decrease in the intracellular GSH levels and an increase in the ophthalmic acid (OPH) levels during hGluc treatment. Interestingly, in the presence of Egt, the decrease of the GSH levels was lower than in cells treated with hGluc alone, and this effect was paralleled by lower OPH levels. Egt was also effective in reducing the cytotoxicity of H2O2 and paraquat (PQT), an inducer of superoxide anion production, showing a similar time-dependent pattern of GSH and OPH levels, although with peaks occurring at different times. Importantly, Egt oxidation generated not only hercynine (EH) but also the sulfonic acid derivative (ESO3H) whose amounts were dependent on the oxidative stress employed. Furthermore, cell-free experiments confirmed the formation of both EH and ESO3H when Egt was reacted with superoxide anion. In summary, these data, by identifying the EH and ESO3H formation in EC exposed to hGluc, highlight the cellular antioxidant properties of Egt, whose peculiar redox behavior makes it an attractive candidate for the prevention of oxidative stress-associated endothelial dysfunction during hyperglycemia.

  • Malvidin and cyanidin derivatives from açai fruit (Euterpe oleracea Mart.) counteract UV-A-induced oxidative stress in immortalized fibroblasts.
    Publication Date: 01/07/2017, on Journal of photochemistry and photobiology. B, Biology
    by Petruk G, Illiano A, Del Giudice R, Raiola A, Amoresano A, Rigano MM, Piccoli R, Monti DM
    DOI: 10.1016/j.jphotobiol.2017.05.013

    UV-A radiations are known to induce cellular oxidative stress, leading to premature skin aging. Consumption of açai fruit (Euterpe oleracea Martius) is known to have many health benefits due to its high level of antioxidants. Herein, we analyzed the ability of phenolic compounds extracted from this fruit to attenuate UV-A-induced oxidative stress in immortalized fibroblast. A methanol/water açai extract was fractionated by HPLC and each fraction tested for anti-oxidant stress activity. Immortalized fibroblasts were pre-incubated with açai fractions and then exposed to UV-A radiations. Açai extract was found to be able to strongly protect cells from oxidative stress. In particular, reactive oxygen species (ROS) production, GSH depletion, lipid peroxidation and no increase in the phosphorylation levels of proteins involved in the oxidative stress pathway was observed in cells pre-incubated with the extract and then irradiated by UV-A. Mass spectrometry analyses of HPLC fractionated extract led us to the identification of malvidin and cyanidin derivatives as the most active molecules able to counteract the negative effects induced by UV-A irradiation. Our results indicate, for the first time, that açai fruit is a valuable natural source for malvidin and cyanidin to be used as anti-stress molecules and represent good candidates for dietary intervention in the prevention of age related skin damage.

  • The brain and the subjective experience of time. A voxel based symptom-lesion mapping study.
    Publication Date: 30/06/2017, on Behavioural brain research
    by Trojano L, Caccavale M, De Bellis F, Crisci C
    DOI: 10.1016/j.bbr.2017.04.031

    The aim of the study was to identify the anatomical bases involved in the subjective experience of time, by means of a voxel based symptom-lesion mapping (VLSM) study on patients with focal brain damage. Thirty-three patients (nineteen with right-hemisphere lesions -RBD, and fourteen with left lesion- LBD) and twenty-eight non-neurological controls (NNC) underwent the semi-structured QUEstionnaire for the Subjective experience of Time (QUEST) requiring retrospective and prospective judgements on self-relevant time intervals. All participants also completed tests to assess general cognitive functioning and two questionnaires to evaluate their emotional state. Both groups of brain-damaged patients achieved significantly different scores from NNC on the time performance, without differences between RBD and LBD. VLSM showed a cluster of voxels located in the right inferior parietal lobule significantly related to errors in the prospective items. The lesion subtraction analysis revealed two different patterns possibly associated with errors in the prospective items (the right inferior parietal cortex, rolandic operculum and posterior middle temporal gyrus) and in the retrospective items (superior middle temporal gyrus, white matter posterior to the insula).

  • SIRT1 and SIRT6 Signaling Pathways in Cardiovascular Disease Protection.
    Publication Date: 29/06/2017, on Antioxidants & redox signaling
    by D'Onofrio N, Servillo L, Balestrieri ML
    DOI: 10.1089/ars.2017.7178

    Oxidative stress represents the common hallmark of pathological conditions associated with cardiovascular disease (CVD), including atherosclerosis, heart failure, hypertension, aging, diabetes, and other vascular system-related diseases. The sirtuin (SIRT) family, comprising seven proteins (SIRT1-SIRT7) sharing a highly conserved nicotinamide adenine dinucleotide (NAD+)-binding catalytic domain, attracted a great attention for the past few years as stress adaptor and epigenetic enzymes involved in the cellular events controlling aging-related disorder, cancer, and CVD. Recent Advances: Among sirtuins, SIRT1 and SIRT6 are the best characterized for their protective roles against inflammation, vascular aging, heart disease, and atherosclerotic plaque development. This latest role has been only recently unveiled for SIRT6. Of interest, in recent years, complex signaling networks controlled by SIRT1 and SIRT6 common to stress resistance, vascular aging, and CVD have emerged.

  • Quantitative determination of free D-Asp, L-Asp and N-methyl-D-aspartate in mouse brain tissues by chiral separation and Multiple Reaction Monitoring tandem mass spectrometry.
    Publication Date: 29/06/2017, on PloS one
    by Fontanarosa C, Pane F, Sepe N, Pinto G, Trifuoggi M, Squillace M, Errico F, Usiello A, Pucci P, Amoresano A
    DOI: 10.1371/journal.pone.0179748

    Several studies have suggested that free d-Asp has a crucial role in N-methyl d-Asp receptor-mediated neurotransmission playing very important functions in physiological and pathological processes. This paper describes the development of an analytical procedure for the direct and simultaneous determination of free d-Asp, l-Asp and N-methyl d-Asp in specimens of different mouse brain tissues using chiral LC-MS/MS in Multiple Reaction Monitoring scan mode. After comparing three procedures and different buffers and extraction solvents, a simple preparation procedure was selected the analytes of extraction. The method was validated by analyzing l-Asp, d-Asp and N-methyl d-Asp recovery at different spiked concentrations (50, 100 and 200 pg/μl) yielding satisfactory recoveries (75-110%), and good repeatability. Limits of detection (LOD) resulted to be 0.52 pg/μl for d-Asp, 0.46 pg/μl for l-Asp and 0.54 pg/μl for NMDA, respectively. Limits of quantification (LOQ) were 1.57 pg/μl for d-Asp, 1.41 pg/μl for l-Asp and 1.64 pg/μl for NMDA, respectively. Different concentration levels were used for constructing the calibration curves which showed good linearity. The validated method was then successfully applied to the simultaneous detection of d-Asp, l-Asp and NMDA in mouse brain tissues. The concurrent, sensitive, fast, and reproducible measurement of these metabolites in brain tissues will be useful to correlate the amount of free d-Asp with relevant neurological processes, making the LC-MS/MS MRM method well suited, not only for research work but also for clinical analyses.

  • Penetrance estimate of LRRK2 p.G2019S mutation in individuals of non-Ashkenazi Jewish ancestry.
    Publication Date: 22/06/2017, on Movement disorders : official journal of the Movement Disorder Society
    by Lee AJ, Wang Y, Alcalay RN, Mejia-Santana H, Saunders-Pullman R, Bressman S, Corvol JC, Brice A, Lesage S, Mangone G, Tolosa E, Pont-Sunyer C, Vilas D, Schüle B, Kausar F, Foroud T, Berg D, Brockmann K, Goldwurm S, Siri C, Asselta R, Ruiz-Martinez J, Mondragón E, Marras C, Ghate T, Giladi N, Mirelman A, Marder K,
    DOI: 10.1002/mds.27059

    Penetrance estimates of the leucine-rich repeat kinase 2 (LRRK2) p.G2019S mutation for PD vary widely (24%-100%). The p.G2019S penetrance in individuals of Ashkenazi Jewish ancestry has been estimated as 25%, adjusted for multiple covariates. It is unknown whether penetrance varies among different ethnic groups. The objective of this study was to estimate the penetrance of p.G2019S in individuals of non-Ashkenazi Jewish ancestry and compare penetrance between Ashkenazi Jews and non-Ashkenazi Jews to age 80.

  • Regulation of sub-compartmental targeting and folding properties of the Prion-like protein Shadoo.
    Publication Date: 16/06/2017, on Scientific reports
    by Pepe A, Avolio R, Matassa DS, Esposito F, Nitsch L, Zurzolo C, Paladino S, Sarnataro D
    DOI: 10.1038/s41598-017-03969-2

    Shadoo (Sho), a member of prion protein family, has been shown to prevent embryonic lethality in Prnp (0/0) mice and to be reduced in the brains of rodents with terminal prion diseases. Sho can also affect PrP structural dynamics and can increase the prion conversion into its misfolded isoform (PrP(Sc)), which is amyloidogenic and strictly related to expression, intracellular localization and association of PrP(C) to lipid rafts. We reasoned that if Sho possesses a natural tendency to convert to amyloid-like forms in vitro, it should be able to exhibit "prion-like" properties, such as PK-resistance and aggregation state, also in live cells. We tested this hypothesis, by different approaches in neuronal cells, finding that Sho shows folding properties partially dependent on lipid rafts integrity whose alteration, as well as proteasomal block, regulated generation of intermediate Sho isoforms and exacerbated its misfolding. Moreover, a 18 kDa isoform of Sho, likely bearing the signal peptide, was targeted to mitochondria by interacting with the molecular chaperone TRAP1 which, in turn controlled Sho dual targeting to ER or mitochondria. Our studies contribute to understand the role of molecular chaperones and of PrP-related folding intermediates in "prion-like" conversion.

  • Role of the C-C chemokine receptor-2 in a murine model of injury-induced osteoarthritis.
    Publication Date: 01/06/2017, on Osteoarthritis and cartilage
    by Longobardi L, Temple JD, Tagliafierro L, Willcockson H, Esposito A, D'Onofrio N, Stein E, Li T, Myers TJ, Ozkan H, Balestrieri ML, Ulici V, Loeser RF, Spagnoli A
    DOI: 10.1016/j.joca.2016.11.004

    We previously found in our embryonic studies that proper regulation of the chemokine CCL12 through its sole receptor CCR2, is critical for joint and growth plate development. In the present study, we examined the role of CCR2 in injury-induced-osteoarthritis (OA).

  • Patients with bicuspid and tricuspid aortic valve exhibit distinct regional microrna signatures in mildly dilated ascending aorta.
    Publication Date: 01/06/2017, on Heart and vessels
    by Albinsson S, Della Corte A, Alajbegovic A, Krawczyk KK, Bancone C, Galderisi U, Cipollaro M, De Feo M, Forte A
    DOI: 10.1007/s00380-016-0942-7

    MicroRNAs are able to modulate gene expression in a range of diseases. We focused on microRNAs as potential contributors to the pathogenesis of ascending aorta (AA) dilatation in patients with stenotic tricuspid (TAV) or bicuspid aortic valve (BAV). Aortic specimens were collected from the 'concavity' and the 'convexity' of mildly dilated AAs and of normal AAs from heart transplant donors. Aortic RNA was analyzed through PCR arrays, profiling the expression of 84 microRNAs involved in cardiovascular disease. An in silico analysis identified the potential microRNA-mRNA interactions and the enriched KEGG pathways potentially affected by microRNA changes in dilated AAs. Distinct signatures of differentially expressed microRNAs are evident in TAV and BAV patients vs. donors, as well as differences between aortic concavity and convexity in patients only. MicroRNA changes suggest a switch of SMC phenotype, with particular reference to TAV concavity. MicroRNA changes potentially affecting mechanotransduction pathways exhibit a higher prevalence in BAV convexity and in TAV concavity, with particular reference to TGF-β1, Hippo, and PI3K/Akt/FoxO pathways. Actin cytoskeleton emerges as potentially affected by microRNA changes in BAV convexity only. MicroRNAs could play distinct roles in BAV and TAV aortopathy, with possible implications in diagnosis and therapy.