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      CRISPR/Cas9 editing of Nf1 gene identifies CRMP2 as a therapeutic target in neurofibromatosis type 1-related pain that is reversed by (S)-Lacosamide :

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          Abstract

          <p class="first" id="P2">Neurofibromatosis type 1 (NF1) is a rare autosomal dominant disease linked to mutations of the <i>Nf1</i> gene. Patients with NF1 commonly experience severe pain. Studies on mice with <i>Nf1</i> haploinsufficiency have been instructive in identifying sensitization of ion channels as a possible cause underlying the heightened pain suffered by patients with NF1. However, behavioral assessments of <i>Nf1</i> <sup>+/−</sup>mice have led to uncertain conclusions about the potential causal role of <i>Nf1</i> in pain. We used the clustered regularly interspaced short palindromic repeats (CRISPR)-associated 9 (CRISPR/Cas9) genome editing system to create and mechanistically characterize a novel rat model of NF1-related pain. Targeted intrathecal delivery of guide RNA/Cas9 nuclease plasmid in combination with a cationic polymer was used to generate allele-specific C-terminal truncation of neurofibromin, the protein encoded by the <i>Nf1</i> gene. Rats with truncation of neurofibromin, showed increases in voltage-gated calcium (specifically N-type or CaV2.2) and voltage-gated sodium (particularly tetrodotoxin-sensitive) currents in dorsal root ganglion neurons. These gains-of-function resulted in increased nociceptor excitability and behavioral hyperalgesia. The cytosolic regulatory protein collapsin response mediator protein 2 (CRMP2) regulates activity of these channels, and also binds to the targeted C-terminus of neurofibromin in a tripartite complex, suggesting a possible mechanism underlying NF1 pain. Prevention of CRMP2 phosphorylation with ( <i>S</i>)-lacosamide resulted in normalization of channel current densities, excitability, as well as of hyperalgesia following CRISPR/ Cas9 truncation of neurofibromin. These studies reveal the protein partners that drive NF1 pain and suggest that CRMP2 is a key target for therapeutic intervention. </p>

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          • Record: found
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          Chronic catheterization of the spinal subarachnoid space.

          To administer drugs into the spinal subarachnoid space of unanesthetized and intact rats and rabbits, a procedure is described whereby a polyethylene catheter (PE-10) may be inserted through a puncture of the atlanto-occipital membrane and secured to the skull. Calibration experiments carried out with bromophenol blue dye, 3H-naloxone and 14C-urea revealed first, that there was little rostro-caudal diffusion of the injectate along the spinal axis and secondly, that even for compounds such as naloxone which can rapidly permeate neural tissues, the levels which do appear in the brain are small following the spinal subarachnoid administration of the drug. Control injections, administered either acutely or repeatedly over a prolonged period of time, had no detectable effect on the animal's behavior. These observations, as well as the lack of pathology in the spinal cords of rats having such catheters for periods of up to 4 months suggests that the implant is well tolerated.
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            • Record: found
            • Abstract: found
            • Article: not found

            The Na(V)1.7 sodium channel: from molecule to man.

            The voltage-gated sodium channel Na(V)1.7 is preferentially expressed in peripheral somatic and visceral sensory neurons, olfactory sensory neurons and sympathetic ganglion neurons. Na(V)1.7 accumulates at nerve fibre endings and amplifies small subthreshold depolarizations, poising it to act as a threshold channel that regulates excitability. Genetic and functional studies have added to the evidence that Na(V)1.7 is a major contributor to pain signalling in humans, and homology modelling based on crystal structures of ion channels suggests an atomic-level structural basis for the altered gating of mutant Na(V)1.7 that causes pain.
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              • Record: found
              • Abstract: found
              • Article: not found

              Neurofibromin regulation of ERK signaling modulates GABA release and learning.

              We uncovered a role for ERK signaling in GABA release, long-term potentiation (LTP), and learning, and show that disruption of this mechanism accounts for the learning deficits in a mouse model for learning disabilities in neurofibromatosis type I (NF1). Our results demonstrate that neurofibromin modulates ERK/synapsin I-dependent GABA release, which in turn modulates hippocampal LTP and learning. An Nf1 heterozygous null mutation, which results in enhanced ERK and synapsin I phosphorylation, increased GABA release in the hippocampus, and this was reversed by pharmacological downregulation of ERK signaling. Importantly, the learning deficits associated with the Nf1 mutation were rescued by a subthreshold dose of a GABA(A) antagonist. Accordingly, Cre deletions of Nf1 showed that only those deletions involving inhibitory neurons caused hippocampal inhibition, LTP, and learning abnormalities. Importantly, our results also revealed lasting increases in GABA release triggered by learning, indicating that the mechanisms uncovered here are of general importance for learning.
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                Author and article information

                Journal
                PAIN
                PAIN
                Ovid Technologies (Wolters Kluwer Health)
                0304-3959
                2017
                December 2017
                : 158
                : 12
                : 2301-2319
                Article
                10.1097/j.pain.0000000000001002
                6362827
                28809766
                30b717b4-0ec9-4138-a566-b88f111c3d9c
                © 2017
                History

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