Disordered Peptides Looking for Their Native Environment: Structural Basis of CB1 Endocannabinoid Receptor Binding to Pepcans.
Publication Date: 16/11/2018, on Frontiers in molecular biosciences
by Emendato A, Guerrini R, Marzola E, Wienk H, Boelens R, Leone S, Picone D
Endocannabinoid peptides, or "pepcans," are endogenous ligands of the CB1 cannabinoid receptor. Depending on their length, they display diverse activity: For instance, the nona-peptide Pepcan-9, also known as hemopressin, is a powerful inhibitor of CB1, whereas the longer variant Pepcan-12, which extends by only three amino acid residues at the N-terminus, acts on both CB1 and CB2 as an allosteric modulator, although with diverse effects. Despite active research on their pharmacological applications, very little is known about structure-activity relationships of pepcans. Different structures have been proposed for the nona-peptide, which has also been reported to form fibrillar aggregates. This might have affected the outcome and reproducibility of bioactivity studies. In an attempt of elucidating the determinants of both biological activity and aggregation propensity of Pepcan-9 and Pepcan-12, we have performed their structure characterization in solvent systems characterized by different polarity and pH. We have found that, while disordered in aqueous environment, both peptides display helical structure in less polar environment, mimicking the proteic receptor milieu. In the case of Pepcan-9, this structure is fully consistent with the observed modulation of the CB1. For Pepcan-12, whose allosteric binding site is still unknown, the presented structure is compatible with the binding at one of the previously proposed allosteric sites on CB1. These findings open the way to structure-driven design of selective peptide modulators of CB1.
Left inferior parietal and posterior temporal cortices mediate the effect of action observation on semantic processing of objects: evidence from rTMS.
Publication Date: 08/11/2018, on Psychological research
by De Bellis F, Magliacano A, Sagliano L, Conson M, Grossi D, Trojano L
Previous studies showed that motor information related to tool use (i.e., functional actions) could affect processing of objects semantic properties, whereas motor information related to grasping or moving tool (i.e., structural actions) cannot. However, little is known about the neural correlates mediating such interaction between motor and semantic information. Here, healthy participants performed a semantic judgment task requiring identification of semantic relations among objects, after observing a functional, a structural or a pointing action prime. In a within-subject design, during prime presentation the participants underwent repetitive transcranial magnetic stimulation (rTMS) over the left supramarginal gyrus (SMG), the left posterior middle temporal gyrus (pMTG) or received sham stimulation. Results showed that in the sham condition observing functional actions (vs. structural and pointing actions) favoured processing of semantic relations based on function similarity (i.e., taxonomic relations), but not of relations based on co-occurrence within an event schema (i.e., thematic relations). Moreover, stimulation of both left SMG and pMTG abolished the effect of functional action primes worsening subsequent judgment about taxonomic relations, and this effect was greater after pMTG stimulation. rTMS did not affect processing of thematic semantic relations. We suggest that action observation triggers activation of functional motor information within left inferior parietal cortex, and that integration between functional motor and conceptual information in left temporal cortex could impact high-level semantic processing of tools.
Controlled Pore Glass-based oligonucleotide affinity support: towards High Throughput Screening methods for the identification of conformation-selective G-quadruplex ligands.
Publication Date: 07/11/2018, on Analytica chimica acta
by Platella C, Musumeci D, Arciello A, Doria F, Freccero M, Randazzo A, Amato J, Pagano B, Montesarchio D
Target selectivity is one of the main challenges in the search for small molecules able to act as effective and non-toxic anticancer and/or antiviral drugs. To achieve this goal, handy, rapid and reliable High Throughput Screening methodologies are needed. We here describe a novel functionalization for the solid phase synthesis of oligonucleotides on Controlled Pore Glass, including a flexible hexaethylene glycol spacer linking the first nucleoside through the nucleobase via a covalent bond stable to the final deprotection step. This allowed us preparing fully deprotected oligonucleotides still covalently attached to their supports. In detail, on this support we performed both the on-line synthesis of different secondary structure-forming oligonucleotides and the affinity chromatography-based screenings of conformation-selective G-quadruplex ligands. By using a fluorescent core-extended naphthalene diimide with different emitting response upon binding to sequences folding into G-quadruplexes of different topologies, we have been able to discriminate not only G-quadruplex vs. duplex DNA structures, but also different G-quadruplex conformations on the glass beads by confocal microscopy.
Bergamot Polyphenols Boost Therapeutic Effects of the Diet on Non-Alcoholic Steatohepatitis (NASH) Induced by "Junk Food": Evidence for Anti-Inflammatory Activity.
Publication Date: 01/11/2018, on Nutrients
by Parafati M, Lascala A, La Russa D, Mignogna C, Trimboli F, Morittu VM, Riillo C, Macirella R, Mollace V, Brunelli E, Janda E
Wrong alimentary behaviors and so-called "junk food" are a driving force for the rising incidence of non-alcoholic fatty liver disease (NAFLD) among children and adults. The "junk food" toxicity can be studied in "cafeteria" (CAF) diet animal model. Young rats exposed to CAF diet become obese and rapidly develop NAFLD. We have previously showed that bergamot () flavonoids, in the form of bergamot polyphenol fraction (BPF), effectively prevent CAF diet-induced NAFLD in rats. Here, we addressed if BPF can accelerate therapeutic effects of weight loss induced by a normocaloric standard chow (SC) diet. 21 rats fed with CAF diet for 16 weeks to induce NAFLD with inflammatory features (NASH) were divided into three groups. Two groups were switched to SC diet supplemented or not with BPF (CAF/SC±BPF), while one group continued with CAF diet (CAF/CAF) for 10 weeks. BPF had no effect on SC diet-induced weight loss, but it accelerated hepatic lipid droplets clearance and reduced blood triglycerides. Accordingly, BPF improved insulin sensitivity, but had little effect on leptin levels. Interestingly, the inflammatory parameters were still elevated in CAF/SC livers compared to CAF/CAF group after 10 weeks of dietary intervention, despite over 90% hepatic fat reduction. In contrast, BPF supplementation decreased hepatic inflammation by reducing interleukin 6 () mRNA expression and increasing anti-inflammatory , which correlated with fewer Kupffer cells and lower inflammatory foci score in CAF/SC+BPF livers compared to CAF/SC group. These data indicate that BPF mediates a specific anti-inflammatory activity in livers recovering from NASH, while it boosts lipid-lowering and anti-diabetic effects of the dietary intervention.
Selegiline in Patients With Disorder of Consciousness: An Open Pilot Study.
Publication Date: 01/11/2018, on The Canadian journal of neurological sciences. Le journal canadien des sciences neurologiques
by Masotta O, Trojano L, Loreto V, Moretta P, Estraneo A
This open study investigated the clinical effects of 10-week selegiline administration in six patients in vegetative state and in four patients in a minimally conscious state, at least 6 months after onset. Clinical outcome was assessed by Coma Recovery Scale-Revised once a week during selegiline administration and 1 month later. Three patients stopped treatment because of possible side effects. After treatment and at 1 month of follow-up, four patients showed improvements in clinical diagnosis, and three patients showed an increase in arousal level only. Selegiline might represent a relatively safe option to enhance arousal and promote recovery in brain-injured patients with disorders of consciousness.
"Pure apathy" and cognitive dysfunctions in Parkinson's disease: A meta-analytic study.
Publication Date: 01/11/2018, on Neuroscience and biobehavioral reviews
by D'Iorio A, Maggi G, Vitale C, Trojano L, Santangelo G
Parkinson's Disease (PD) is characterized by motor and non-motor symptoms such as cognitive deficit and behavioural disturbances. Apathy seems to be related to cognitive impairment, but some studies failed to confirm the relationship due to different methodological procedures across studies. A meta-analysis on 8 studies was performed to explore the cognitive correlates of apathy without depression and dementia (pure apathy). Global cognitive function, memory, executive functions, processing speed/attention/working memory, visuospatial abilities and language were the outcomes. The effect size of the relationship between "pure apathy" and reduced global cognitive functioning, executive functions, processing speed/attention/working memory, visuospatial functions, long-term verbal memory was moderate, whereas apathy was strongly associated with inhibition dysfunctioning. Our results revealed a strong association between "pure apathy" and cognitive dysfunctions, particularly deficit of memory and executive functions related to altered prefronto-subcortical circuitries.
Publication Date: 01/11/2018, on Stem cells (Dayton, Ohio)
by Squillaro T, Finicelli M, Peluso G, Galderisi U
Validation of the Nine Hole Peg Test as a measure of dexterity in myotonic dystrophy type 1.
Publication Date: 01/11/2018, on Neuromuscular disorders : NMD
by Cutellè C, Rastelli E, Gibellini M, Greco G, Frezza E, Botta A, Terracciano C, Massa R
We aimed to validate the Nine Hole Peg Test as a measure of dexterity in myotonic dystrophy type 1 (DM1). Fifty patients with adult-onset, genetically confirmed DM1 were evaluated by Nine Hole Peg Test and re-evaluated at one week. Myotonia was not a limiting factor. The first test was compared with that performed by normal subjects (n = 28). Contextually, patients underwent handgrip and three-finger pinch assessments by handheld dynamometer. The Nine Hole Peg Test showed high intra-rater and inter-rater reliability in DM1 [ICC 0.86/0.83 for dominant and 0.90/0.88 for non-dominant hand, respectively]. Inverse correlation with handgrip and pinch strength values (r = -0.4; p < 0.01) and direct correlation with Muscular Impairment Rating Scale (r = 0.4; p < 0.01) were found for both DH and NDH. The test was able to differentiate severe DM1 patients, stratified by extent of muscle impairment, from mildly affected and normal controls, with a sensitivity of 97% and 95% for dominant hand and non-dominant hand, respectively (p < 0.0001). In conclusion, we showed that the Nine Hole Peg Test is a reliable, valid and sensitive test of dexterity in DM1, and that it can be considered as a candidate outcome measure to monitor natural history of disease and, possibly, therapeutic response in clinical trials.
The extreme hyper-reactivity of Cys94 in lysozyme avoids its amorphous aggregation.
Publication Date: 30/10/2018, on Scientific reports
by Bocedi A, Cattani G, Martelli C, Cozzolino F, Castagnola M, Pucci P, Ricci G
Many proteins provided with disulfide bridges in the native state undergo amorphous irreversible aggregation when these bonds are not formed. Here we show that egg lysozyme displays a clever strategy to prevent this deleterious aggregation during the nascent phase when disulfides are still absent. In fact, when the reduced protein assembles into a molten globule state, its cysteines acquire strong hyper-reactivity towards natural disulfides. The most reactive residue, Cys94, reacts with oxidized glutathione (GSSG) 3000 times faster than an unperturbed protein cysteine. A low pK of its sulfhydryl group (6.6/7.1) and a productive complex with GSSG (K = 0.3 mM), causes a fast glutathionylation of this residue (t = 3 s) and a complete inhibition of the protein aggregation. Other six cysteines display 70 times higher reactivity toward GSSG. The discovery of extreme hyper-reactivity in cysteines only devoted to structural roles opens new research fields for Alzheimer's and Parkinson diseases.
Meldonium improves Huntington's disease mitochondrial dysfunction by restoring peroxisome proliferator-activated receptor γ coactivator 1α expression.
Publication Date: 26/10/2018, on Journal of cellular physiology
by Di Cristo F, Finicelli M, Digilio FA, Paladino S, Valentino A, Scialò F, D'Apolito M, Saturnino C, Galderisi U, Giordano A, Melone MAB, Peluso G
Mitochondrial dysfunction seems to play a fundamental role in the pathogenesis of neurodegeneration in Huntington's disease (HD). We assessed possible neuroprotective actions of meldonium, a small molecule affecting mitochondrial fuel metabolism, in in vitro and in vivo HD models. We found that meldonium was able to prevent cytotoxicity induced by serum deprivation, to reduce the accumulation of mutated huntingtin (mHtt) aggregates, and to upregulate the expression of peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α) in mHTT-expressing cells. The PGC-1α increase was accompanied by the increment of mitochondrial mass and by the rebalancing of mitochondrial dynamics with a promotion of the mitochondrial fusion. Meldonium-induced PGC-1α significantly alleviated motor dysfunction and prolonged the survival of a transgenic HD Drosophila model in which mHtt expression in the nervous system led to progressive motor performance deficits. Our study strongly suggests that PGC-1α, as a master coregulator of mitochondrial biogenesis, energy homeostasis, and antioxidant defense, is a potential therapeutic target in HD.
Oxidative Stress Causes Enhanced Secretion of YB-1 Protein that Restrains Proliferation of Receiving Cells.
Publication Date: 22/10/2018, on Genes
by Guarino AM, Troiano A, Pizzo E, Bosso A, Vivo M, Pinto G, Amoresano A, Pollice A, La Mantia G, Calabrò V
The prototype cold-shock Y-box binding protein 1 (YB-1) is a multifunctional protein that regulates a variety of fundamental biological processes including cell proliferation and migration, DNA damage, matrix protein synthesis and chemotaxis. The plethora of functions assigned to YB-1 is strictly dependent on its subcellular localization. In resting cells, YB-1 localizes to cytoplasm where it is a component of messenger ribonucleoprotein particles. Under stress conditions, YB-1 contributes to the formation of stress granules (SGs), cytoplasmic foci where untranslated messenger RNAs (mRNAs) are sorted or processed for reinitiation, degradation, or packaging into ribonucleoprotein particles (mRNPs). Following DNA damage, YB-1 translocates to the nucleus and participates in DNA repair thereby enhancing cell survival. Recent data show that YB-1 can also be secreted and YB-1-derived polypeptides are found in plasma of patients with sepsis and malignancies. Here we show that in response to oxidative insults, YB-1 assembly in SGs is associated with an enhancement of YB-1 protein secretion. An enriched fraction of extracellular YB-1 (exYB-1) significantly inhibited proliferation of receiving cells and such inhibition was associated to a G2/M cell cycle arrest, induction of p21WAF and reduction of Np63 protein level. All together, these data show that acute oxidative stress causes sustained release of YB-1 as a paracrine/autocrine signal that stimulate cell cycle arrest.
Multimodal Neuroimaging Approach to Variability of Functional Connectivity in Disorders of Consciousness: A PET/MRI Pilot Study.
Publication Date: 18/10/2018, on Frontiers in neurology
by Cavaliere C, Kandeepan S, Aiello M, Ribeiro de Paula D, Marchitelli R, Fiorenza S, Orsini M, Trojano L, Masotta O, St Lawrence K, Loreto V, Chronik BA, Nicolai E, Soddu A, Estraneo A
Behavioral assessments could not suffice to provide accurate diagnostic information in individuals with disorders of consciousness (DoC). Multimodal neuroimaging markers have been developed to support clinical assessments of these patients. Here we present findings obtained by hybrid fludeoxyglucose (FDG-)PET/MR imaging in three severely brain-injured patients, one in an unresponsive wakefulness syndrome (UWS), one in a minimally conscious state (MCS), and one patient emerged from MCS (EMCS). Repeated behavioral assessment by means of Coma Recovery Scale-Revised and neurophysiological evaluation were performed in the two weeks before and after neuroimaging acquisition, to ascertain that clinical diagnosis was stable. The three patients underwent one imaging session, during which two resting-state fMRI (rs-fMRI) blocks were run with a temporal gap of about 30 min. rs-fMRI data were analyzed with a graph theory approach applied to nine independent networks. We also analyzed the benefits of concatenating the two acquisitions for each patient or to select for each network the graph strength map with a higher ratio of fitness. Finally, as for clinical assessment, we considered the best functional connectivity pattern for each network and correlated graph strength maps to FDG uptake. Functional connectivity analysis showed several differences between the two rs-fMRI acquisitions, affecting in a different way each network and with a different variability for the three patients, as assessed by ratio of fitness. Moreover, combined PET/fMRI analysis demonstrated a higher functional/metabolic correlation for patients in EMCS and MCS compared to UWS. In conclusion, we observed for the first time, through a test-retest approach, a variability in the appearance and temporal/spatial patterns of resting-state networks in severely brain-injured patients, proposing a new method to select the most informative connectivity pattern.
Exploring the conformational behaviour and aggregation properties of lipid-conjugated AS1411 aptamers.
Publication Date: 15/10/2018, on International journal of biological macromolecules
by Riccardi C, Musumeci D, Russo Krauss I, Piccolo M, Irace C, Paduano L, Montesarchio D
AS1411 is a nucleolin-binding aptamer which attracted great interest as active targeting ligand for the selective delivery of therapeutic agents to tumour cells. In this work we selected three AS1411 derivatives 5'-conjugated with lipophilic tails and studied their properties in view of their application in liposomial formulations and/or lipid coated-nanoparticles for targeted therapies. The conformational behaviour of these AS1411 analogs has been investigated in comparison with the unmodified aptamer by CD, UV, PAGE, SEC-HPLC, DLS and thioflavin T (ThT) fluorescence assays to get insight in their secondary structure and aggregation properties. This study has been performed in pseudo-physiological buffers mimicking the extra- and intracellular environments, and at different concentrations in the μM range, paying special attention to the effects of the lipophilic tail on the overall aptamer conformation. The 5'-lipidated AS1411 derivatives proved to fold into stable, parallel unimolecular G-quadruplex structures, forming large aggregates, mainly micelles, at conc. >10 μM. Preliminary bioscreenings on selected cancer cells showed that these derivatives are less cytotoxic than AS1411, but maintain a similar biological behaviour. This study demonstrated that lipophilic tails dramatically favour the formation of AS1411 aggregates, however not impairing the formation and thermal stability of its peculiar G4 motifs.
Metabolic syndrome, Mediterranean diet, and polyphenols: Evidence and perspectives.
Publication Date: 14/10/2018, on Journal of cellular physiology
by Finicelli M, Squillaro T, Di Cristo F, Di Salle A, Melone MAB, Galderisi U, Peluso G
Metabolic syndrome (MetS) is defined as the co-occurrence of metabolic risk factors that includes insulin resistance, hyperinsulinemia, impaired glucose tolerance, type 2 diabetes mellitus, dyslipidemia, and visceral obesity. The clinical significance of MetS consists of identifying a subgroup of patients sharing a common physiopathological state predisposing to chronic diseases. Clinical and scientific studies pinpoint lifestyle modification as an effective strategy aiming to reduce several features accountable for the risk of MetS onset. Among the healthy dietary patterns, the Mediterranean diet (MedDiet) emerges in terms of beneficial properties associated with longevity. Current evidence highlights the protective effect exerted by MedDiet on the different components of MetS. Interestingly, the effect exerted by polyphenols contained within the representative MedDiet components (i.e., olive oil, red wine, and nuts) seems to be accountable for the beneficial properties associated to this dietary pattern. In this review, we aim to summarize the principal evidence regarding the effectiveness of MedDiet-polyphenols in preventing or delaying the physiopathological components accountable for MetS onset. These findings may provide useful insights concerning the health properties of MedDiet-polyphenols as well as the novel targets destined to a tailored approach to MetS.
The Role of Wearable Devices in Multiple Sclerosis.
Publication Date: 10/10/2018, on Multiple sclerosis international
by Sparaco M, Lavorgna L, Conforti R, Tedeschi G, Bonavita S
Multiple sclerosis (MS) is the most common neurological disorder in young adults. The prevalence of walking impairment in people with MS (pwMS) is estimated between 41% and 75%. To evaluate the walking capacity in pwMS, the patient reported outcomes (PROs) and performance-based tests (i.e., the 2-minute walk test, the 6-minute walk test, the Timed 25-Foot Walk Test, the Timed Up and Go Test, and the Six Spot Step Test) could be used. However, some studies point out that the results of both performance-based tests and objective measures (i.e., by accelerometer) could not reflect patient reports of walking performance and impact of MS on daily life. This review analyses different motion sensors embedded in smartphones and motion wearable device (MWD) that can be useful to measure free-living walking behavior, to evaluate falls, fatigue, sedentary lifestyle, exercise, and quality of sleep in everyday life of pwMS. Caveats and limitations of MWD such as variable accuracy, user adherence, power consumption and recharging, noise susceptibility, and data management are discussed as well.