Publications by authors named "Nunzio Iraci"

69 Publications

Interaction of selected terpenoids with two SARS-CoV-2 key therapeutic targets: An in silico study through molecular docking and dynamics simulations.

Comput Biol Med 2021 07 8;134:104538. Epub 2021 Jun 8.

Dipartimento di Scienze Chimiche, Biologiche, Farmaceutiche ed Ambientali, Università di Messina, Messina, Italy.

The outbreak of COVID-19 disease caused by SARS-CoV-2, along with the lack of targeted medicaments, forced the scientific world to search for new antiviral formulations. In the current emergent situation, drug repurposing of well-known traditional and/or approved drugs could be the most effective strategy. Herein, through computational approaches, we aimed to screen 14 natural compounds from limonoids and terpenoids class for their ability to inhibit the key therapeutic target proteins of SARS-CoV-2. Among these, some limonoids, namely deacetylnomilin, ichangin and nomilin, and the terpenoid β-amyrin provided good interaction energies with SARS-CoV-2 3CL hydrolase (Mpro) in molecular dynamic simulation. Interestingly, deacetylnomilin and ichangin showed direct interaction with the catalytic dyad of the enzyme so supporting their potential role in preventing SARS-CoV-2 replication and growth. On the contrary, despite the good affinity with the spike protein RBD site, all the selected phytochemicals lose contact with the amino acid residues over the course of 120ns-long molecular dynamics simulations therefore suggesting they scarcely can interfere in SARS-CoV-2 binding to the ACE2 receptor. The in silico analyses of docking score and binding energies, along with predicted pharmacokinetic profiles, indicate that these triterpenoids might have potential as inhibitors of SARS-CoV-2 Mpro, recommending further in vitro and in vivo investigations for a complete understanding and confirmation of their inhibitory potential.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.compbiomed.2021.104538DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8186839PMC
July 2021

Neural stem cells traffic functional mitochondria via extracellular vesicles.

PLoS Biol 2021 Apr 7;19(4):e3001166. Epub 2021 Apr 7.

Department of Clinical Neurosciences and NIHR Biomedical Research Centre, University of Cambridge, United Kingdom.

Neural stem cell (NSC) transplantation induces recovery in animal models of central nervous system (CNS) diseases. Although the replacement of lost endogenous cells was originally proposed as the primary healing mechanism of NSC grafts, it is now clear that transplanted NSCs operate via multiple mechanisms, including the horizontal exchange of therapeutic cargoes to host cells via extracellular vesicles (EVs). EVs are membrane particles trafficking nucleic acids, proteins, metabolites and metabolic enzymes, lipids, and entire organelles. However, the function and the contribution of these cargoes to the broad therapeutic effects of NSCs are yet to be fully understood. Mitochondrial dysfunction is an established feature of several inflammatory and degenerative CNS disorders, most of which are potentially treatable with exogenous stem cell therapeutics. Herein, we investigated the hypothesis that NSCs release and traffic functional mitochondria via EVs to restore mitochondrial function in target cells. Untargeted proteomics revealed a significant enrichment of mitochondrial proteins spontaneously released by NSCs in EVs. Morphological and functional analyses confirmed the presence of ultrastructurally intact mitochondria within EVs with conserved membrane potential and respiration. We found that the transfer of these mitochondria from EVs to mtDNA-deficient L929 Rho0 cells rescued mitochondrial function and increased Rho0 cell survival. Furthermore, the incorporation of mitochondria from EVs into inflammatory mononuclear phagocytes restored normal mitochondrial dynamics and cellular metabolism and reduced the expression of pro-inflammatory markers in target cells. When transplanted in an animal model of multiple sclerosis, exogenous NSCs actively transferred mitochondria to mononuclear phagocytes and induced a significant amelioration of clinical deficits. Our data provide the first evidence that NSCs deliver functional mitochondria to target cells via EVs, paving the way for the development of novel (a)cellular approaches aimed at restoring mitochondrial dysfunction not only in multiple sclerosis, but also in degenerative neurological diseases.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1371/journal.pbio.3001166DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8055036PMC
April 2021

High-Resolution Respirometry Reveals MPP Mitochondrial Toxicity Mechanism in a Cellular Model of Parkinson's Disease.

Int J Mol Sci 2020 Oct 22;21(21). Epub 2020 Oct 22.

Department of Biological, Geological and Environmental Sciences, University of Catania, V.le Andrea Doria 6, 95125 Catania, Italy.

MPP is the active metabolite of MPTP, a molecule structurally similar to the herbicide Paraquat, known to injure the dopaminergic neurons of the nigrostriatal system in Parkinson's disease models. Within the cells, MPP accumulates in mitochondria where it inhibits complex I of the electron transport chain, resulting in ATP depletion and neuronal impairment/death. So far, MPP is recognized as a valuable tool to mimic dopaminergic degeneration in various cell lines. However, despite a large number of studies, a detailed characterization of mitochondrial respiration in neuronal cells upon MPP treatment is still missing. By using high-resolution respirometry, we deeply investigated oxygen consumption related to each respiratory state in differentiated neuroblastoma cells exposed to the neurotoxin. Our results indicated the presence of extended mitochondrial damage at the inner membrane level, supported by increased LEAK respiration, and a drastic drop in oxygen flow devoted to ADP phosphorylation in respirometry measurements. Furthermore, prior to complex I inhibition, an enhancement of complex II activity was observed, suggesting the occurrence of some compensatory effect. Overall our findings provide a mechanistic insight on the mitochondrial toxicity mediated by MPP, relevant for the standardization of studies that employ this neurotoxin as a disease model.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/ijms21217809DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7659480PMC
October 2020

Extracellular Vesicles as Nanotherapeutics for Parkinson's Disease.

Biomolecules 2020 09 16;10(9). Epub 2020 Sep 16.

Department of Biomedical and Biotechnological Sciences (BIOMETEC), University of Catania, Torre Biologica, Via Santa Sofia 97, 95125 Catania, Italy.

Extracellular vesicles (EVs) are naturally occurring membranous structures secreted by normal and diseased cells, and carrying a wide range of bioactive molecules. In the central nervous system (CNS), EVs are important in both homeostasis and pathology. Through receptor-ligand interactions, direct fusion, or endocytosis, EVs interact with their target cells. Accumulating evidence indicates that EVs play crucial roles in the pathogenesis of many neurodegenerative disorders (NDs), including Parkinson's disease (PD). PD is the second most common ND, characterized by the progressive loss of dopaminergic (DAergic) neurons within the Substantia Nigra pars compacta (SNpc). In PD, EVs are secreted by both neurons and glial cells, with either beneficial or detrimental effects, via a complex program of cell-to-cell communication. The functions of EVs in PD range from their etiopathogenetic relevance to their use as diagnostic tools and innovative carriers of therapeutics. Because they can cross the blood-brain barrier, EVs can be engineered to deliver bioactive molecules (e.g., small interfering RNAs, catalase) within the CNS. This review summarizes the latest findings regarding the role played by EVs in PD etiology, diagnosis, prognosis, and therapy, with a particular focus on their use as novel PD nanotherapeutics.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/biom10091327DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7563168PMC
September 2020

Mastering the Tools: Natural versus Artificial Vesicles in Nanomedicine.

Adv Healthc Mater 2020 09 31;9(18):e2000731. Epub 2020 Aug 31.

Department of Biomedical and Biotechnological Sciences, University of Catania, Torre Biologica, Via S. Sofia 97, Catania, 95125, Italy.

Naturally occurring extracellular vesicles and artificially made vesicles represent important tools in nanomedicine for the efficient delivery of biomolecules and drugs. Since its first appearance in the literature 50 years ago, the research on vesicles is progressing at a fast pace, with the main goal of developing carriers able to protect cargoes from degradation, as well as to deliver them in a time- and space-controlled fashion. While natural occurring vesicles have the advantage of being fully compatible with their host, artificial vesicles can be easily synthetized and functionalized according to the target to reach. Research is striving to merge the advantages of natural and artificial vesicles, in order to provide a new generation of highly performing vesicles, which would improve the therapeutic index of transported molecules. This progress report summarizes current manufacturing techniques used to produce both natural and artificial vesicles, exploring the promises and pitfalls of the different production processes. Finally, pros and cons of natural versus artificial vesicles are discussed and compared, with special regard toward the current applications of both kinds of vesicles in the healthcare field.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/adhm.202000731DOI Listing
September 2020

Glia-Derived Extracellular Vesicles in Parkinson's Disease.

J Clin Med 2020 Jun 21;9(6). Epub 2020 Jun 21.

Department of Biomedical and Biotechnological Sciences (BIOMETEC), University of Catania, Torre Biologica, Via S. Sofia 97, 95125 Catania, Italy.

Glial cells are fundamental players in the central nervous system (CNS) development and homeostasis, both in health and disease states. In Parkinson's disease (PD), a dysfunctional glia-neuron crosstalk represents a common final pathway contributing to the chronic and progressive death of dopaminergic (DAergic) neurons of the substantia nigra pars compacta (SNpc). Notably, glial cells communicating with each other by an array of molecules, can acquire a "beneficial" or "destructive" phenotype, thereby enhancing neuronal death/vulnerability and/or exerting critical neuroprotective and neuroreparative functions, with mechanisms that are actively investigated. An important way of delivering messenger molecules within this glia-neuron cross-talk consists in the secretion of extracellular vesicles (EVs). EVs are nano-sized membranous particles able to convey a wide range of molecular cargoes in a controlled way, depending on the specific donor cell and the microenvironmental milieu. Given the dual role of glia in PD, glia-derived EVs may deliver molecules carrying various messages for the vulnerable/dysfunctional DAergic neurons. Here, we summarize the state-of-the-art of glial-neuron interactions and glia-derived EVs in PD. Also, EVs have the ability to cross the blood brain barrier (BBB), thus acting both within the CNS and outside, in the periphery. In these regards, this review discloses the emerging applications of EVs, with a special focus on glia-derived EVs as potential carriers of new biomarkers and nanotherapeutics for PD.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/jcm9061941DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7356371PMC
June 2020

Corrigendum to "NCp7: targeting a multitask protein for next-generation anti-HIV drug development part 2. Noncovalent inhibitors and nucleic acid binders" [Drug Discov. Today 23(2018) 687-695].

Drug Discov Today 2019 Dec 17. Epub 2019 Dec 17.

Department of Heterorganic Chemistry, Centre of Molecular and Macromolecular Studies, Lodz, Poland. Electronic address:

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.drudis.2019.12.002DOI Listing
December 2019

Synthesis and Pharmacological Characterization of Conformationally Restricted Retigabine Analogues as Novel Neuronal Kv7 Channel Activators.

J Med Chem 2020 01 24;63(1):163-185. Epub 2019 Dec 24.

Department of Neuroscience, Reproductive Sciences and Dentistry , University Federico II of Naples , Via Pansini, 5 , 80131 Naples , Italy.

Kv7 K channels represent attractive pharmacological targets for the treatment of different neurological disorders, including epilepsy. In this paper, 42 conformationally restricted analogues of the prototypical Kv7 activator retigabine have been synthesized and tested by electrophysiological patch-clamp experiments as Kv7 agonists. When compared to retigabine (0.93 ± 0.43 μM), the ECs for Kv7.2 current enhancements by compound (0.08 ± 0.04 μM) were lower, whereas no change in potency was observed for (0.63 ± 0.07 μM). In addition, compared to retigabine, and showed also higher potency in activating heteromeric Kv7.2/Kv7.3 and homomeric Kv7.4 channels. Molecular modeling studies provided new insights into the chemical features required for optimal interaction at the binding site. Stability studies evidenced improved chemical stability of and in comparison with retigabine. Overall, the present results highlight that the 5-alkylamidoindole moiety provides a suitable pharmacophoric scaffold for the design of chemically stable, highly potent and selective Kv7 agonists.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1021/acs.jmedchem.9b00796DOI Listing
January 2020

Diselenides and Benzisoselenazolones as Antiproliferative Agents and Glutathione-S-Transferase Inhibitors.

Molecules 2019 Aug 11;24(16). Epub 2019 Aug 11.

Division of Organic Chemistry, Centre of Molecular and Macromolecular Studies, Polish Academy of Science, Sienkiewicza, 112, 90-363 Lodz, Poland.

A series of variously functionalized selenium-containing compounds were purposely synthesized and evaluated against a panel of cancer cell lines. Most of the compounds showed an interesting cytotoxicity profile with compound showing a potent activity on MCF7 cells. The ethyl amino derivative acts synergistically with -platin and inhibits the GST enzyme with a potency that well correlates with the cytotoxicity observed in MCF7 cells. A computational analysis suggests a possible binding mode on the GST enzyme. As the main outcome of the present study, the ethyl amino derivative emerged as a valid lead compound for further, future developments.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/molecules24162914DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6721112PMC
August 2019

Tumor Targeting by Peptide-Decorated Gold Nanoparticles.

Mol Pharm 2019 06 29;16(6):2430-2444. Epub 2019 Apr 29.

School of Pharmacy , University of Camerino , via Gentile III da Varano , 62032 Camerino , Italy.

Cancer remains one of the most important challenges in biomedical sciences. Chemotherapeutic agents are very potent molecules that exhibit a significant level of toxicity in numerous tissues of the body, particularly in those characterized by high proliferative activity, such as the bone marrow. The scenario is even more complex in the case of the central nervous system, and in particular brain tumors, where the blood brain barrier limits the efficacy of drug therapies. Integrins, transmembrane proteins widely expressed in different types of cancer (glioblastoma, melanoma, and breast cancer), regulate the angiogenic process and play a pivotal role in tumor growth and invasion. Here, we report a nanotechnology strategy based on the use of AuNPs decorated with an arginine-glycine-aspartic acid-like peptide for the diagnosis and treatment of cancer. Two hours after administration in mice, the accumulation of the peptide-decorated NPs in the subcutaneous tumor was ∼4-fold higher than that of uncoated particles and ∼1.4-fold higher than that of PEGylated particles. Also, in the case of the intracranial tumor model, interesting results were obtained. Indeed, 2 h after administration, the amount of peptide-decorated particles in the brain was 1.5-fold that of undecorated particles and 5-fold that of PEGylated particles. In conclusion, this preliminary study demonstrates the high potential of this carrier developed for diagnostic and therapeutic applications.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1021/acs.molpharmaceut.9b00047DOI Listing
June 2019

Identification of a Potent Tryptophan-Based TRPM8 Antagonist With in Vivo Analgesic Activity.

J Med Chem 2018 Jul 10;61(14):6140-6152. Epub 2018 Jul 10.

Department of Pharmacy , University Federico II of Naples , Via D. Montesano 49 , 80131 Naples , Italy.

TRPM8 has been implicated in nociception and pain and is currently regarded as an attractive target for the pharmacological treatment of neuropathic pain syndromes. A series of analogues of N, N'-dibenzyl tryptamine 1, a potent TRPM8 antagonist, was prepared and screened using a fluorescence-based in vitro assay based on menthol-evoked calcium influx in TRPM8 stably transfected HEK293 cells. The tryptophan derivative 14 was identified as a potent (IC 0.2 ± 0.2 nM) and selective TRPM8 antagonist. In vivo, 14 showed significant target coverage in both an icilin-induced WDS (at 1-30 mg/kg s.c.) and oxaliplatin-induced cold allodynia (at 0.1-1 μg s.c.) mice models. Molecular modeling studies identified the putative binding mode of these antagonists, suggesting that they could influence an interaction network between the S1-4 transmembrane segments and the TRP domains of the channel subunits. The tryptophan moiety provides a new pharmacophoric scaffold for the design of highly potent modulators of TRPM8-mediated pain.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1021/acs.jmedchem.8b00545DOI Listing
July 2018

De novo gain-of-function variants in KCNT2 as a novel cause of developmental and epileptic encephalopathy.

Ann Neurol 2018 06;83(6):1198-1204

Institute of Human Genetics, University of Leipzig Hospitals and Clinics, Leipzig, Germany.

Variants in several potassium channel genes have been found in developmental and epileptic encephalopathies (DEE). We report on 2 females with de novo variants in KCNT2 with West syndrome followed by Lennox-Gastaut syndrome or with DEE with migrating focal seizures. After in vitro analysis suggested quinidine-responsive gain-of-function effects, we treated 1 of the girls with quinidine add-on therapy and achieved marked clinical improvements. This suggests that the new spectrum of KCNT2-related disorders do not only share similar phenotypic and in vitro functional and pharmacological features with previously known KCNT1-related disorders, but also represents a further example for possible precision medicine approaches. Ann Neurol 2018;83:1198-1204.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/ana.25248DOI Listing
June 2018

Pharmacological Agents Targeting the Cellular Prion Protein.

Pathogens 2018 Mar 7;7(1). Epub 2018 Mar 7.

Dulbecco Telethon Laboratory of Prions and Amyloids, Centre for Integrative Biology (CIBIO), University of Trento, 38123 Trento, Italy.

Prion diseases are associated with the conversion of the cellular prion protein (PrP), a glycoprotein expressed at the surface of a wide variety of cell types, into a misfolded conformer (the scrapie form of PrP, or PrP) that accumulates in brain tissues of affected individuals. PrP is a self-catalytic protein assembly capable of recruiting native conformers of PrP, and causing their rearrangement into new PrP molecules. Several previous attempts to identify therapeutic agents against prion diseases have targeted PrP, and a number of compounds have shown potent anti-prion effects in experimental models. Unfortunately, so far, none of these molecules has successfully been translated into effective therapies for prion diseases. Moreover, mounting evidence suggests that PrP might be a difficult pharmacological target because of its poorly defined structure, heterogeneous composition, and ability to generate different structural conformers (known as prion strains) that can elude pharmacological intervention. In the last decade, a less intuitive strategy to overcome all these problems has emerged: targeting PrP, the common substrate of any prion strain replication. This alternative approach possesses several technical and theoretical advantages, including the possibility of providing therapeutic effects also for other neurodegenerative disorders, based on recent observations indicating a role for PrP in delivering neurotoxic signals of different misfolded proteins. Here, we provide an overview of compounds claimed to exert anti-prion effects by directly binding to PrP, discussing pharmacological properties and therapeutic potentials of each chemical class.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/pathogens7010027DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5874753PMC
March 2018

Microglia Polarization, Gene-Environment Interactions and Wnt/β-Catenin Signaling: Emerging Roles of Glia-Neuron and Glia-Stem/Neuroprogenitor Crosstalk for Dopaminergic Neurorestoration in Aged Parkinsonian Brain.

Front Aging Neurosci 2018 12;10:12. Epub 2018 Feb 12.

Oasi ResearchInstitute-IRCCS, Troina, Italy.

Neuroinflammatory processes are recognized key contributory factors in Parkinson's disease (PD) physiopathology. While the causes responsible for the progressive loss of midbrain dopaminergic (mDA) neuronal cell bodies in the subtantia nigra pars compacta are poorly understood, aging, genetics, environmental toxicity, and particularly inflammation, represent prominent etiological factors in PD development. Especially, reactive astrocytes, microglial cells, and infiltrating monocyte-derived macrophages play dual beneficial/harmful effects, via a panel of pro- or anti-inflammatory cytokines, chemokines, neurotrophic and neurogenic transcription factors. Notably, with age, microglia may adopt a potent neurotoxic, pro-inflammatory "primed" (M1) phenotype when challenged with inflammatory or neurotoxic stimuli that hamper brain's own restorative potential and inhibit endogenous neurorepair mechanisms. In the last decade we have provided evidence for a major role of microglial crosstalk with astrocytes, mDA neurons and neural stem progenitor cells (NSCs) in the MPTP- (1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-) mouse model of PD, and identified Wnt/β-catenin signaling, a pivotal morphogen for mDA neurodevelopment, neuroprotection, and neuroinflammatory modulation, as a critical actor in glia-neuron and glia-NSCs crosstalk. With age however, Wnt signaling and glia-NSC-neuron crosstalk become dysfunctional with harmful consequences for mDA neuron plasticity and repair. These findings are of importance given the deregulation of Wnt signaling in PD and the emerging link between most PD related genes, Wnt signaling and inflammation. Especially, in light of the expanding field of microRNAs and inflammatory PD-related genes as modulators of microglial-proinflammatory status, uncovering the complex molecular circuitry linking PD and neuroinflammation will permit the identification of new druggable targets for the cure of the disease. Here we summarize recent findings unveiling major microglial inflammatory and oxidative stress pathways converging in the regulation of Wnt/β-catenin signaling, and reciprocally, the ability of Wnt signaling pathways to modulate microglial activation in PD. Unraveling the key factors and conditons promoting the switch of the proinflammatory M1 microglia status into a neuroprotective and regenerative M2 phenotype will have important consequences for neuroimmune interactions and neuronal outcome under inflammatory and/or neurodegenerative conditions.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fnagi.2018.00012DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5816064PMC
February 2018

Macrophage-Derived Extracellular Succinate Licenses Neural Stem Cells to Suppress Chronic Neuroinflammation.

Cell Stem Cell 2018 03 22;22(3):355-368.e13. Epub 2018 Feb 22.

Department of Clinical Neurosciences and NIHR Biomedical Research Centre, University of Cambridge, Cambridge, UK. Electronic address:

Neural stem cell (NSC) transplantation can influence immune responses and suppress inflammation in the CNS. Metabolites, such as succinate, modulate the phenotype and function of immune cells, but whether and how NSCs are also activated by such immunometabolites to control immunoreactivity and inflammatory responses is unclear. Here, we show that transplanted somatic and directly induced NSCs ameliorate chronic CNS inflammation by reducing succinate levels in the cerebrospinal fluid, thereby decreasing mononuclear phagocyte (MP) infiltration and secondary CNS damage. Inflammatory MPs release succinate, which activates succinate receptor 1 (SUCNR1)/GPR91 on NSCs, leading them to secrete prostaglandin E2 and scavenge extracellular succinate with consequential anti-inflammatory effects. Thus, our work reveals an unexpected role for the succinate-SUCNR1 axis in somatic and directly induced NSCs, which controls the response of stem cells to inflammatory metabolic signals released by type 1 MPs in the chronically inflamed brain.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.stem.2018.01.020DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5842147PMC
March 2018

Kv7.3 Compound Heterozygous Variants in Early Onset Encephalopathy Reveal Additive Contribution of C-Terminal Residues to PIP-Dependent K Channel Gating.

Mol Neurobiol 2018 Aug 30;55(8):7009-7024. Epub 2018 Jan 30.

Department of Medicine and Health Science, University of Molise, Campobasso, Italy.

Over one hundred mutations in the Kv7.2 (KCNQ2) gene encoding for phosphatidylinositol 4,5-bisphosphate (PIP)-sensitive voltage-gated K channel subunits have been identified in early-onset epilepsies with wide phenotypic variability. By contrast, only few mutations in the closely related Kv7.3 (KCNQ3) gene have been reported, mostly associated with typical benign familial neonatal seizures (BFNS). We herein describe a patient affected by early onset epileptic encephalopathy (EOEE) carrying two Kv7.3 missense mutations (p.Val359Leu/V359L and p.Asp542Asn/D542N) in compound heterozygosis, each inherited from an asymptomatic parent. Patch-clamp recordings from transiently transfected CHO cells showed that, when incorporated in physiologically relevant Kv7.2 + Kv7.3 heteromeric channels, expression of Kv7.3 V359L or Kv7.3 D542N subunits failed to affect current density, whereas a significant decrease was instead observed when these mutant subunits were both simultaneously present. Modeling and functional experiments revealed that each variant decreased PIP-dependent current regulation, with additive effects when the two were co-expressed. Moreover, expression of Kv7.2 subunits carrying the D535N variant previously described in three sporadic EOEE cases prompted functional changes more dramatic when compared to those of the corresponding D542N variant in Kv7.3, but similar to those observed when both Kv7.3 V359L and Kv7.3 D542N subunits were expressed together. Finally, the Kv7 activator retigabine restored channel dysfunction induced by each Kv7.2 or Kv7.3 variant(s). These results provide a plausible molecular explanation for the apparent recessive inheritance of the phenotype in the family investigated, and a rational basis for personalized therapy with Kv7 channel activators in EOEE patients carrying loss-of-function mutations in Kv7.2 or Kv7.3.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s12035-018-0883-5DOI Listing
August 2018

NCp7: targeting a multitask protein for next-generation anti-HIV drug development part 2. Noncovalent inhibitors and nucleic acid binders.

Drug Discov Today 2018 03 8;23(3):687-695. Epub 2018 Jan 8.

Department of Heterorganic Chemistry, Centre of Molecular and Macromulecular Studies, Lodz, Poland. Electronic address:

Nucleocapsid protein 7 (NCp7) represents a viable target not yet reached by the currently available antiretrovirals. It is a small and highly basic protein, which is essential for multiple stages of the viral replicative cycle, with its structure preserved in all viral strains, including clinical isolates. NCp7 can be inhibited covalently, noncovalently and by shielding the nucleic acid (NA) substrates of its chaperone activity. Although covalent NCp7 inhibitors have already been detailed in the first part of this review series, the focus here is based on noncovalent and NA-binder inhibitors and on the analysis of the NCp7 3D structure to deliver fruitful insights for future drug design strategies.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.drudis.2018.01.022DOI Listing
March 2018

microRNAs in Parkinson's Disease: From Pathogenesis to Novel Diagnostic and Therapeutic Approaches.

Int J Mol Sci 2017 Dec 13;18(12). Epub 2017 Dec 13.

Department of Biomedical and Biotechnological Sciences (BIOMETEC), University of Catania, Torre Biologica, Via S. Sofia 97, 95125 Catania, Italy.

Parkinson's disease (PD) is the most prevalent central nervous system (CNS) movement disorder and the second most common neurodegenerative disease overall. PD is characterized by the progressive loss of dopaminergic (DAergic) neurons in the substantia nigra pars compacta (SNpc) within the midbrain, accumulation of alpha-synuclein (α-SYN) in Lewy bodies and neurites and excessive neuroinflammation. The neurodegenerative processes typically begin decades before the appearance of clinical symptoms. Therefore, the diagnosis is achievable only when the majority of the relevant DAergic neurons have already died and for that reason available treatments are only palliative at best. The causes and mechanism(s) of this devastating disease are ill-defined but complex interactions between genetic susceptibility and environmental factors are considered major contributors to the etiology of PD. In addition to the role of classical gene mutations in PD, the importance of regulatory elements modulating gene expression has been increasingly recognized. One example is the critical role played by microRNAs (miRNAs) in the development and homeostasis of distinct populations of neurons within the CNS and, in particular, in the context of PD. Recent reports demonstrate how distinct miRNAs are involved in the regulation of PD genes, whereas profiling approaches are unveiling variations in the abundance of certain miRNAs possibly relevant either to the onset or to the progression of the disease. In this review, we provide an overview of the miRNAs recently found to be implicated in PD etiology, with particular focus on their potential relevance as PD biomarkers, as well as their possible use in PD targeted therapy.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/ijms18122698DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5751299PMC
December 2017

NCp7: targeting a multitasking protein for next-generation anti-HIV drug development part 1: covalent inhibitors.

Drug Discov Today 2018 02 28;23(2):260-271. Epub 2017 Oct 28.

Department of Pharmaceutical Sciences, University of Perugia, Perugia, Italy.

The major internal component of the HIV virion core is the nucleocapsid protein 7 (NCp7), a small, highly basic protein that is essential for multiple stages of the viral replicative cycle, and whose structure is preserved in all viral strains, including clinical isolates from therapy-experienced patients. This key protein is recognised as a potential target for an effective next-generation antiretroviral therapy, because it could offer the possibility to develop broad-spectrum agents that are less prone to select for resistant strains. Here, we provide a comprehensive overview of the covalent NCp7 inhibitors that have emerged over the past 25 years of drug discovery campaigns, emphasising, where possible, their structure-activity relationships (SARs) and pharmacophoric features.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.drudis.2017.10.017DOI Listing
February 2018

A novel community driven software for functional enrichment analysis of extracellular vesicles data.

J Extracell Vesicles 2017 26;6(1):1321455. Epub 2017 May 26.

Department of Biopathology and Medical Biotechnologies, University of Palermo, Palermo, Italy.

Bioinformatics tools are imperative for the in depth analysis of heterogeneous high-throughput data. Most of the software tools are developed by specific laboratories or groups or companies wherein they are designed to perform the required analysis for the group. However, such software tools may fail to capture "what the community needs in a tool". Here, we describe a novel community-driven approach to build a comprehensive functional enrichment analysis tool. Using the existing FunRich tool as a template, we invited researchers to request additional features and/or changes. Remarkably, with the enthusiastic participation of the community, we were able to implement 90% of the requested features. FunRich enables plugin for extracellular vesicles wherein users can download and analyse data from Vesiclepedia database. By involving researchers early through community needs software development, we believe that comprehensive analysis tools can be developed in various scientific disciplines.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1080/20013078.2017.1321455DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5505018PMC
May 2017

Extracellular vesicles are independent metabolic units with asparaginase activity.

Nat Chem Biol 2017 Sep 3;13(9):951-955. Epub 2017 Jul 3.

Wellcome Trust-Medical Research Council Stem Cell Institute, Department of Clinical Neurosciences-Division of Stem Cell Neurobiology, and NIHR Biomedical Research Centre, University of Cambridge, Cambridge, UK.

Extracellular vesicles (EVs) are membrane particles involved in the exchange of a broad range of bioactive molecules between cells and the microenvironment. Although it has been shown that cells can traffic metabolic enzymes via EVs, much remains to be elucidated with regard to their intrinsic metabolic activity. Accordingly, herein we assessed the ability of neural stem/progenitor cell (NSC)-derived EVs to consume and produce metabolites. Our metabolomics and functional analyses both revealed that EVs harbor L-asparaginase activity, catalyzed by the enzyme asparaginase-like protein 1 (Asrgl1). Critically, we show that Asrgl1 activity is selective for asparagine and is devoid of glutaminase activity. We found that mouse and human NSC EVs traffic Asrgl1. Our results demonstrate, for the first time, that NSC EVs function as independent metabolic units that are able to modify the concentrations of critical nutrients, with the potential to affect the physiology of their microenvironment.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/nchembio.2422DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5563455PMC
September 2017

Pharmacophore-Based Repositioning of Approved Drugs as Novel Staphylococcus aureus NorA Efflux Pump Inhibitors.

J Med Chem 2017 02 8;60(4):1598-1604. Epub 2017 Feb 8.

Department of Pharmaceutical Sciences, University of Perugia , Via del Liceo 1, 06123 Perugia, Italy.

An intriguing opportunity to address antimicrobial resistance is represented by the inhibition of efflux pumps. Focusing on NorA, the most important efflux pump of Staphylococcus aureus, an efflux pump inhibitors (EPIs) library was used for ligand-based pharmacophore modeling studies. By exploitation of the obtained models, an in silico drug repositioning approach allowed for the identification of novel and potent NorA EPIs.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1021/acs.jmedchem.6b01439DOI Listing
February 2017

Early-onset epileptic encephalopathy caused by a reduced sensitivity of Kv7.2 potassium channels to phosphatidylinositol 4,5-bisphosphate.

Sci Rep 2016 12 1;6:38167. Epub 2016 Dec 1.

Department of Medicine and Health Sciences, University of Molise, Campobasso, Italy.

Kv7.2 and Kv7.3 subunits underlie the M-current, a neuronal K current characterized by an absolute functional requirement for phosphatidylinositol 4,5-bisphosphate (PIP). Kv7.2 gene mutations cause early-onset neonatal seizures with heterogeneous clinical outcomes, ranging from self-limiting benign familial neonatal seizures to severe early-onset epileptic encephalopathy (Kv7.2-EE). In this study, the biochemical and functional consequences prompted by a recurrent variant (R325G) found independently in four individuals with severe forms of neonatal-onset EE have been investigated. Upon heterologous expression, homomeric Kv7.2 R325G channels were non-functional, despite biotin-capture in Western blots revealed normal plasma membrane subunit expression. Mutant subunits exerted dominant-negative effects when incorporated into heteromeric channels with Kv7.2 and/or Kv7.3 subunits. Increasing cellular PIP levels by co-expression of type 1γ PI(4)P5-kinase (PIP5K) partially recovered homomeric Kv7.2 R325G channel function. Currents carried by heteromeric channels incorporating Kv7.2 R325G subunits were more readily inhibited than wild-type channels upon activation of a voltage-sensitive phosphatase (VSP), and recovered more slowly upon VSP switch-off. These results reveal for the first time that a mutation-induced decrease in current sensitivity to PIP is the primary molecular defect responsible for Kv7.2-EE in individuals carrying the R325G variant, further expanding the range of pathogenetic mechanisms exploitable for personalized treatment of Kv7.2-related epilepsies.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/srep38167DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5131271PMC
December 2016

Focus on Extracellular Vesicles: Physiological Role and Signalling Properties of Extracellular Membrane Vesicles.

Int J Mol Sci 2016 Feb 6;17(2):171. Epub 2016 Feb 6.

Wellcome Trust-Medical Research Council Stem Cell Institute, Clifford Allbutt Building-Cambridge Biosciences Campus, Department of Clinical Neurosciences, and NIHR Biomedical Research Centre, University of Cambridge, Hills Road CB2 0PY, UK.

Extracellular vesicles (EVs) are a heterogeneous population of secreted membrane vesicles, with distinct biogenesis routes, biophysical properties and different functions both in physiological conditions and in disease. The release of EVs is a widespread biological process, which is conserved across species. In recent years, numerous studies have demonstrated that several bioactive molecules are trafficked with(in) EVs, such as microRNAs, mRNAs, proteins and lipids. The understanding of their final impact on the biology of specific target cells remains matter of intense debate in the field. Also, EVs have attracted great interest as potential novel cell-free therapeutics. Here we describe the proposed physiological and pathological functions of EVs, with a particular focus on their molecular content. Also, we discuss the advances in the knowledge of the mechanisms regulating the secretion of EV-associated molecules and the specific pathways activated upon interaction with the target cell, highlighting the role of EVs in the context of the immune system and as mediators of the intercellular signalling in the brain.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/ijms17020171DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4783905PMC
February 2016

Tryptamine-Based Derivatives as Transient Receptor Potential Melastatin Type 8 (TRPM8) Channel Modulators.

J Med Chem 2016 Mar 17;59(5):2179-91. Epub 2016 Feb 17.

Department of Pharmacy, University Federico II of Naples , Via D. Montesano 49, 80131, Naples, Italy.

Pharmacological modulation of the transient receptor potential melastatin type 8 (TRPM8) is currently under investigation as a new approach for the treatment of pain and other diseases. In this study, a series of N-substituted tryptamines was prepared to explore the structural requirements determining TRPM8 modulation. Using a fluorescence-based screening assay, we identified two compounds acting as an activator (2-(1H-indol-3-yl)-N-(4-phenoxybenzyl)ethanamine, 21) or an inhibitor (N,N-dibenzyl-2-(1H-indol-3-yl)ethanamine, 12) of calcium influx in HEK293 cells. In patch-clamp recordings, compound 21 displayed a significantly higher potency (EC50 = 40 ± 4 μM) and a similar efficacy when compared to menthol; by contrast, compound 12 produced a concentration-dependent inhibition of menthol-induced TRPM8 currents (IC50 = 367 ± 24 nM). Molecular modeling studies using a homology model of a single rat TRPM8 subunit identified a putative binding site located between the VSD and the TRP box, disclosing differences in the binding modes for the agonist and the antagonist.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1021/acs.jmedchem.5b01914DOI Listing
March 2016

Acellular approaches for regenerative medicine: on the verge of clinical trials with extracellular membrane vesicles?

Stem Cell Res Ther 2015 Dec 2;6:227. Epub 2015 Dec 2.

Department of Clinical Neurosciences; Wellcome Trust-Medical Research Council Stem Cell Institute, University of Cambridge, Clifford Allbutt Building-Cambridge Biosciences Campus, Hills Road, Cambridge, CB2 0PY, UK.

Extracellular vesicles (EVs) are a heterogeneous population of naturally occurring secreted small vesicles, with distinct biophysical properties and different functions both in physiology and under pathological conditions. In recent years, a number of studies have demonstrated that EVs might hold remarkable potential in regenerative medicine by acting as therapeutically promising nanodrugs. Understanding their final impact on the biology of specific target cells as well as clarification of their overall therapeutic impact remains a matter of intense debate. Here we review the key principles of EVs in physiological and pathological conditions with a specific highlight on the most recently described mechanisms regulating some of the EV-mediated effects. First, we describe the current debates and the upcoming research on EVs as potential novel therapeutics in regenerative medicine, either as unmodified agents or as functionalized small carriers for targeted drug delivery. Moreover, we address a number of safety aspects and regulatory limitations related to the novel nature of EV-mediated therapeutic applications. Despite the emerging possibilities of EV treatments, these issues need to be overcome in order to allow their safe and successful application in future explorative clinical studies.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1186/s13287-015-0232-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4668616PMC
December 2015

Design and Synthesis of DiselenoBisBenzamides (DISeBAs) as Nucleocapsid Protein 7 (NCp7) Inhibitors with anti-HIV Activity.

J Med Chem 2015 Dec 10;58(24):9601-14. Epub 2015 Dec 10.

Department of Pharmaceutical Sciences, University of Perugia , Via del Liceo 1, Perugia 06100, Italy.

The interest in the synthesis of Se-containing compounds is growing with the discovery of derivatives exhibiting various biological activities. In this manuscript, we have identified a series of 2,2'-diselenobisbenzamides (DISeBAs) as novel HIV retroviral nucleocapsid protein 7 (NCp7) inhibitors. Because of its pleiotropic functions in the whole viral life cycle and its mutation intolerant nature, NCp7 represents a target of great interest which is not reached by any anti-HIV agent in clinical use. Using the diselenobisbenzoic scaffold, amino acid, and benzenesulfonamide derivatives were prepared and biologically profiled against different models of HIV infection. The incorporation of amino acids such as glycine and glutamate into DISeBAs 7 and 8 resulted in selective anti-HIV activity against both acutely and chronically infected cells as well as an interesting virucidal effect. DISeBAs demonstrated broad antiretroviral activity, encompassing HIV-1 drug-resistant strains including clinical isolates, as well as simian immunodeficiency virus (SIV). Time of addition experiments, along with the observed dose dependent inhibition of the Gag precursor proper processing, confirmed that their mechanism of action is based on NCp7 inhibition.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1021/acs.jmedchem.5b01183DOI Listing
December 2015

p38α MAPK and Type I Inhibitors: Binding Site Analysis and Use of Target Ensembles in Virtual Screening.

Molecules 2015 Aug 31;20(9):15842-61. Epub 2015 Aug 31.

Department of Pharmaceutical Sciences, University of Perugia, Via A. Fabretti, 48, 06123 Perugia, Italy.

Mitogen-activated protein kinase p38α plays an essential role in the regulation of pro-inflammatory signaling, and selective blockade of this kinase could be efficacious in many pathological processes. Despite considerable research efforts focused on the discovery and development of p38α MAPK inhibitors, no drug targeting this protein has been approved for clinical use so far. We herein analyze the available crystal structures of p38α MAPK in complex with ATP competitive type I inhibitors, getting insights into ATP binding site conformation and its influence on automated molecular docking results. The use of target ensembles, rather than single conformations, resulted in a performance improvement in both the ability to reproduce experimental bound conformations and the capability of mining active molecules from compound libraries. The information gathered from this study can be exploited in structure-based drug discovery programs having as the ultimate aim the identification of novel p38α MAPK type I inhibitors.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/molecules200915842DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6331920PMC
August 2015

A Comprehensive Structural Overview of p38α MAPK in Complex with Type I Inhibitors.

ChemMedChem 2015 Jun 9;10(6):957-69. Epub 2015 Apr 9.

Department of Pharmaceutical Sciences, University of Perugia, Via A. Fabretti 48, 06123 Perugia (Italy).

p38α mitogen-activated protein kinase (MAPK) is a well-recognized therapeutic target for the treatment of autoimmune and inflammatory diseases. Over the past two decades, tremendous efforts have been focused on the discovery and development of small-molecule p38α MAPK inhibitors, although currently no drugs targeting this protein are clinically available. Therefore, the identification of novel chemotypes that are able to inhibit p38α MAPK function is still of great therapeutic significance. With the objective to support drug discovery programs aimed at identifying new immunomodulators acting on p38α MAPK, herein we present a complete overview of the available crystal structures of this protein in complex with ATP-site type I inhibitors. The 85 available complexes are classified by chemotype and experimental binding mode, and the ligand-protein interactions are discussed using the most representative inhibitors. The type and frequency of key inhibitor features are analyzed to give a final summary of the chemical requirements of promising p38α MAPK inhibitors. The proposed pharmacophore can be exploited to enhance the opportunities to identify novel type I inhibitors of p38α MAPK.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/cmdc.201500030DOI Listing
June 2015
-->