Project description:Comparison of L5 DRG gene expression profiles at day 14 from SNT treated animals vs. sham controls. This experiment is part of larger study, where the expression profiles of three disparate models of neuropathic pain (SNT, VZV infection and gp120+ddC) are compared in order to find genes that are responsible for mechanical hypersensitivity
Project description:Comparison of L5 DRG gene expression profiles at day 14 from gp120+ddC treated animals vs sham (SA + saline) treated animals.<br>This experiment is part of larger study, where the expression profiles of three disparate models of neuropathic pain (SNT, VZV infection and gp120+ddC) are compared in order to find genes that are responsible for mechanical hypersensitivity formation/maintenance.
Project description:Chronic neuropathic pain’s impact, persistence, and limited treatments render it relevant for gene therapy. Here, we describe the development and application of self-assembling dimeric peptide inhibitors of the pain-associated scaffolding protein PICK1 (protein interacting with C-kinase 1) delivered by adeno-associated viral (AAV) vectors. In mice, these peptides prevented mechanical allodynia in inflammatory and neuropathic pain models and reversed neuropathic pain for up to one year. Targeting of somatosensory pain pathways relieved pain without overt side effects, while selective transduction of dorsal root ganglion (DRG) neurons was sufficient for providing pain relief. Using proteomic and phosphoproteomic analysis of DRG tissue, we identified protein kinase C alpha (PRKCA) substrate candidate, that potentially shape this pain-relieving phenotype. We also confirmed PICK1 expression and peptide target engagement in mice and human donor tissue, supporting the potential of AAV-based PICK1 inhibitors as a clinically meaningful strategy for neuropathic pain conditions.
Project description:Chronic neuropathic pain’s impact, persistence, and limited treatments render it relevant for gene therapy. Here, we describe the development and application of self-assembling dimeric peptide inhibitors of the pain-associated scaffolding protein PICK1 (protein interacting with C-kinase 1) delivered by adeno-associated viral (AAV) vectors. In mice, these peptides prevented mechanical allodynia in inflammatory and neuropathic pain models and reversed neuropathic pain for up to one year. Targeting of somatosensory pain pathways relieved pain without overt side effects, while selective transduction of dorsal root ganglion (DRG) neurons was sufficient for providing pain relief. Using proteomic and phosphoproteomic analysis of DRG tissue, we identified protein kinase C alpha (PRKCA) substrate candidate, that potentially shape this pain-relieving phenotype. We also confirmed PICK1 expression and peptide target engagement in mice and human donor tissue, supporting the potential of AAV-based PICK1 inhibitors as a clinically meaningful strategy for neuropathic pain conditions.
Project description:Histone deacetylase inhibitors (HDACIs) interfere with the epigenetic process of histone acetylation and are known to have analgesic properties in models of chronic inflammatory pain. The aim of this study was to determine whether these compounds could also affect neuropathic pain. Different class I HDACIs were delivered intrathecally into rat spinal cord in models of traumatic nerve injury and antiretroviral drug-induced peripheral neuropathy (stavudine, d4T). Mechanical and thermal hypersensitivity was attenuated by 40% to 50% as a result of HDACI treatment, but only if started before any insult. The drugs globally increased histone acetylation in the spinal cord, but appeared to have no measurable effects in relevant dorsal root ganglia in this treatment paradigm, suggesting that any potential mechanism should be sought in the central nervous system. Microarray analysis of dorsal cord RNA revealed the signature of the specific compound used (MS-275) and suggested that its main effect was mediated through HDAC1. Taken together, these data support a role for histone acetylation in the emergence of neuropathic pain. n = 4, HDACi treated vs. vehicle treated. Injured ipsilateral DRG after L5 spinal nerve transection. Spinal cord tissue was run in a separate Affymetrix experiment.
Project description:Histone deacetylase inhibitors (HDACIs) interfere with the epigenetic process of histone acetylation and are known to have analgesic properties in models of chronic inflammatory pain. The aim of this study was to determine whether these compounds could also affect neuropathic pain. Different class I HDACIs were delivered intrathecally into rat spinal cord in models of traumatic nerve injury and antiretroviral drug-induced peripheral neuropathy (stavudine, d4T). Mechanical and thermal hypersensitivity was attenuated by 40% to 50% as a result of HDACI treatment, but only if started before any insult. The drugs globally increased histone acetylation in the spinal cord, but appeared to have no measurable effects in relevant dorsal root ganglia in this treatment paradigm, suggesting that any potential mechanism should be sought in the central nervous system. Microarray analysis of dorsal cord RNA revealed the signature of the specific compound used (MS-275) and suggested that its main effect was mediated through HDAC1. Taken together, these data support a role for histone acetylation in the emergence of neuropathic pain. n = 4, HDACi treated vs. vehicle treated. Ipsilateral dorsal spinal cord tissue after L5 spinal nerve transection, DRG tissue was run in a separate Affymetrix experiment.
Project description:Two out-bred rat selection lines were separated to produce different hypersensitivity phenotypes following nerve injury. These lines were termed High Pain and Low Pain (HP or LP). Each sub-strain was either subject to a Sham surgery or a Spinal Nerve Ligation (SNL) surgery to the L4 and L5 spinal nerves. Three days following surgery L4/L5 Dorsal Root Ganglia (DRG) were dissected from these animals. For the rat line separation protocol see: Devor M, Raber P (1990) Heritability of symptoms in an experimental model of neuropathic pain. Pain 42:51-67. 12 Hybridizations, 3 per condition; Sham HP DRG; 3 day SNL HP DRG; Sham LP DRG; 3 day SNL LP DRG.