Characterizing NaV1.7 antisense analgesia through antagonist binding, mRNA expression, and neuraxial distribution
Kaue Malange, Julia Borges Paes Lemes, Briana Noble, Yuvicza Anchondo, Carlos E. Morado-Urbina, Saee Jadhav, Saurabh Yadav, Jingrui Ma, Vineet Augustine, Sara A. Dochnal, Chiraag Kambalimath, Marie Duong, Pedro Alvarez, Bethany Fitzsimmons, Curt Mazur, Holly B. Kordasiewicz, Kim Dore, Hien T. Zhao, Tony Yaksh
Kaue Malange, Julia Borges Paes Lemes, Briana Noble, Yuvicza Anchondo, Carlos E. Morado-Urbina, Saee Jadhav, Saurabh Yadav, Jingrui Ma, Vineet Augustine, Sara A. Dochnal, Chiraag Kambalimath, Marie Duong, Pedro Alvarez, Bethany Fitzsimmons, Curt Mazur, Holly B. Kordasiewicz, Kim Dore, Hien T. Zhao, Tony Yaksh
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Research Article Cell biology Neuroscience

Characterizing NaV1.7 antisense analgesia through antagonist binding, mRNA expression, and neuraxial distribution

Abstract

Genome-targeting strategies to address NaV1.7-mediated signaling in nociceptive afferents are of great clinical interest given its high selectivity and persistent analgesic outcomes. In the present work, we analyze concentration-dependent effects of suppressing primary afferent NaV1.7 using the intrathecal delivery of an antisense oligonucleotide (ASO) on pain behaviors and demonstrate that NaV1.7 ASOs are likely to modulate pain traffic by blocking afferent signaling at the dorsal root ganglion (DRG) level. Intrathecal NaV1.7 ASOs induced a concentration-dependent gradient of knockdown in DRGs (lumbar to cervical) of Scn9a mRNA and ATTO488-ProTx-II binding in small DRG neurons, and a suppression of pain behaviors initiated by mechanical compression, inflammation, and the NaV1.7 agonist OD-1. The rostro-caudal reduction in mRNA correlated with ASO distribution, with implications for dose-related analgesic profiles. Marked reduction in DRG NaV1.7 binding was seen after intrathecal delivery of an ASO optimal dose, with high selectivity for small DRG neurons. Changes in sciatic nerve NaV1.7 binding were not detected, indicating a pain traffic modulation likely happening due to a block of afferent signaling at the DRG level.

Authors

Kaue Malange, Julia Borges Paes Lemes, Briana Noble, Yuvicza Anchondo, Carlos E. Morado-Urbina, Saee Jadhav, Saurabh Yadav, Jingrui Ma, Vineet Augustine, Sara A. Dochnal, Chiraag Kambalimath, Marie Duong, Pedro Alvarez, Bethany Fitzsimmons, Curt Mazur, Holly B. Kordasiewicz, Kim Dore, Hien T. Zhao, Tony Yaksh

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Figure 2

ASOs targeting NaV1.7 affect nociceptive behaviors.

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ASOs targeting NaV1.7 affect nociceptive behaviors. (A and B) The intrat...
(A and B) The intrathecal injections of different NaV1.7 ASO doses (100–3000 μg in 10 μL) significantly knocked down Scn9a mRNA in DRGs and decreased formalin second phase. In B: αP < 0.05, compared to NaV 1.7 ASO 300 μg group. (C) The nociceptive behavior evoked by the selective NaV1.7 agonist, OD-1, was significantly affected by the intrathecal knockdown of NaV1.7 with 1000 and 3000 μg ASO doses. (D and E) These doses tested had similar outcomes in decreasing the flinching behavior triggered by intradermal injection of OD-1, with similar degrees in mRNA knockdown at the DRG (D) and spinal cord (E). (F) On a 4-week time course, the intrathecal NaV1.7 ASO markedly increased the paw withdrawal thresholds in male and female rats at weeks 2 and 4 after the ASO delivery. (G and H) These events are correlated with a knockdown of Scn9a at both DRGs (G) and spinal cord (H) in comparison with mismatch and PBS controls. (I) In an extra set of experiments, the intrathecal NaV1.7 ASO (1000 μg/10 μL, intrathecal, 14 days prior to testing) replicates the analgesic profile of the NaV1.7 antagonist 488PTx-II (2 μg/10 μL, intrathecal) in the carrageenan model (100 μg/50 μL, subcutaneously, right hind paw). αP < 0.05, compared to PTx-II or NaV 1.7 ASO groups during carrageenan testing. (J) Again, the effects of NaV1.7 ASO correlates with a significant knockdown in Scn9a mRNA in the ipsilateral L3–L5 DRGs harvested from mismatch and NaV1.7 ASO immediately after testing. Results shown as mean ± SD. *P < 0.05; **P < 0.01; ***P < 0.001 for comparison with PBS by 2-way ANOVA with Tukey’s post hoc test (A) or 1-way ANOVA with Tukey’s post hoc test (B–E).