title: Purinergic Modulation of Spinal Neuroglial Maladaptive Plasticity Following Peripheral Nerve Injury.
abstract: Modulation of spinal reactive gliosis following peripheral nerve injury (PNI) is a promising strategy to restore synaptic homeostasis. Oxidized ATP (OxATP), a nonselective antagonist of purinergic P2X receptors, was found to recover a neuropathic behavior following PNI. We investigated the role of intraperitoneal (i.p.) OxATP treatment in restoring the expression of neuronal and glial markers in the mouse spinal cord after sciatic spared nerve injury (SNI). Using in vivo two-photon microscopy, we imaged Ca(2+) transients in neurons and astrocytes of the dorsal horn of spinal cord at rest and upon right hind paw electrical stimulation in sham, SNI, and OxATP-treated mice. Neuropathic behavior was investigated by von Frey and thermal plantar test. Glial [glial fibrillary acidic protein (GFAP), ionized calcium-binding adaptor molecule 1 (Iba1)] and GABAergic [vesicular GABA transporter (vGAT) and glutamic acid decarboxylase 65/76 (GAD65/67)] markers and glial [glutamate transporter (GLT1) and GLAST] and neuronal amino acid [EAAC1, vesicular glutamate transporter 1 (vGLUT1)] transporters have been evaluated. In SNI mice, we found (i) increased glial response, (ii) decreased glial amino acid transporters, and (iii) increased levels of neuronal amino acid transporters, and (iv) in vivo analysis of spinal neurons and astrocytes showed a persistent increase of Ca(2+) levels. OxATP administration reduced glial activation, modulated the expression of glial and neuronal glutamate/GABA transporters, restored neuronal and astrocytic Ca(2+) levels, and prevented neuropathic behavior. In vitro studies validated that OxATP (i) reduced levels of reactive oxygen species (ROS), (ii) reduced astrocytic proliferation, (iii) increase vGLUT expression. All together, these data support the correlation between reactive gliosis and perturbation of the spinal synaptic homeostasis and the role played by the purinergic system in modulating spinal plasticity following PNI.
authors.affiliation: Laboratory of Neuronal Networks, Department of Mental and Physical Health and Preventive Medicine, Second University of Naples, via L. Armanni, 5, 80138, Naples, Italy.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Cirillo
authors.affiliation: Laboratory of Neuroscience "R. Levi-Montalcini", Department of Biotechnology and Biosciences, University of Milano-Bicocca, Milan, Italy.|SYSBIO, Centre of Systems Biology, University of Milano-Bicocca, Milan, Italy.
authors.forename: Anna Maria
authors.initials: AM
authors.lastname: Colangelo
authors.affiliation: Laboratory of Neuroscience "R. Levi-Montalcini", Department of Biotechnology and Biosciences, University of Milano-Bicocca, Milan, Italy.|SYSBIO, Centre of Systems Biology, University of Milano-Bicocca, Milan, Italy.
authors.forename: Miluscia
authors.initials: M
authors.lastname: Berbenni
authors.affiliation: Laboratory of Neuroscience "R. Levi-Montalcini", Department of Biotechnology and Biosciences, University of Milano-Bicocca, Milan, Italy.|SYSBIO, Centre of Systems Biology, University of Milano-Bicocca, Milan, Italy.
authors.forename: Vita Maria
authors.initials: VM
authors.lastname: Ippolito
authors.affiliation: Laboratory of Neuronal Networks, Department of Mental and Physical Health and Preventive Medicine, Second University of Naples, via L. Armanni, 5, 80138, Naples, Italy.
authors.forename: Ciro
authors.initials: C
authors.lastname: De Luca
authors.affiliation: Laboratory of Neuronal Networks, Department of Mental and Physical Health and Preventive Medicine, Second University of Naples, via L. Armanni, 5, 80138, Naples, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Verdesca
authors.affiliation: Laboratory of Neuronal Networks, Department of Mental and Physical Health and Preventive Medicine, Second University of Naples, via L. Armanni, 5, 80138, Naples, Italy.
authors.forename: Leonilde
authors.initials: L
authors.lastname: Savarese
authors.affiliation: Laboratory of Neuroscience "R. Levi-Montalcini", Department of Biotechnology and Biosciences, University of Milano-Bicocca, Milan, Italy.|SYSBIO, Centre of Systems Biology, University of Milano-Bicocca, Milan, Italy.
authors.forename: Lilia
authors.initials: L
authors.lastname: Alberghina
authors.affiliation: Talpiot Medical Leadership Program, The Chaim Sheba Medical Center, Tel HaShomer, Israel.|Department of Neurology and the J. Sagol Neuroscience Center, The Chaim Sheba Medical Center, Tel HaShomer, Israel.
authors.forename: Nicola
authors.initials: N
authors.lastname: Maggio
authors.affiliation: Laboratory of Neuronal Networks, Department of Mental and Physical Health and Preventive Medicine, Second University of Naples, via L. Armanni, 5, 80138, Naples, Italy. michele.papa@unina2.it.|SYSBIO, Centre of Systems Biology, University of Milano-Bicocca, Milan, Italy. michele.papa@unina2.it.
authors.forename: Michele
authors.initials: M
authors.lastname: Papa
mesh_terms: D000255:Adenosine Triphosphate / Q000031:analogs & derivatives / Q000494:pharmacology; D026905:Amino Acid Transport Systems / Q000096:biosynthesis / Q000235:genetics; D000596:Amino Acids / Q000378:metabolism; D000818:Animals; D001253:Astrocytes / Q000187:drug effects / Q000502:physiology; D015415:Biomarkers; D002118:Calcium / Q000378:metabolism; D015536:Down-Regulation; D005911:Gliosis / Q000503:physiopathology / Q000517:prevention & control*; D006706:Homeostasis; D006358:Hot Temperature; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009419:Nerve Tissue Proteins / Q000096:biosynthesis / Q000235:genetics / Q000502:physiology*; D009437:Neuralgia / Q000209:etiology / Q000503:physiopathology; D009473:Neuronal Plasticity / Q000187:drug effects / Q000502:physiology*; D009474:Neurons / Q000378:metabolism / Q000473:pathology; D017288:Pain Threshold / Q000187:drug effects / Q000502:physiology; D010543:Peroneal Nerve / Q000293:injuries*; D058920:Purinergic P2X Receptor Antagonists / Q000494:pharmacology; D017382:Reactive Oxygen Species / Q000378:metabolism; D058469:Receptors, Purinergic P2X / Q000502:physiology*; D013116:Spinal Cord / Q000503:physiopathology* / Q000648:ultrastructure; D013979:Tibial Nerve / Q000293:injuries*
chemical_list: D026905:Amino Acid Transport Systems; D000596:Amino Acids; D015415:Biomarkers; D009419:Nerve Tissue Proteins; D058920:Purinergic P2X Receptor Antagonists; D017382:Reactive Oxygen Species; D058469:Receptors, Purinergic P2X; C017199:2',3'-dialdehyde ATP; D000255:Adenosine Triphosphate; D002118:Calcium
keywords: Calcium imaging; Maladaptive plasticity; Nerve injury; Neuroglial network; Reactive astrocytosis; Synaptic homeostasis