Clinical and animal studies have shown that acupuncture may benefit controlling neuropathic pain. However, the underlying molecular mechanisms are poorly understood. In a well-established mouse unilateral tibial nerve injury (TNI) model, we confirmed the efficacy of electroacupuncture (EA) in reducing mechanical allodynia and measured methylation and hydroxy-methylation levels in the primary somatosensory cortex (S1) and anterior cingulate cortex (ACC), two cortical regions critically involved in pain processing. TNI resulted in increased DNA methylation of both the contra- and ipsilateral S1, while EA only reduced contralateral S1 methylation. RNA sequencing of the S1 and ACC identified differentially expressed genes related to energy metabolism, inflammation, synapse function, and neural plasticity and repair. One week of daily EA decreased or increased the majority of up- or downregulated genes, respectively, in both cortical regions. Validations of two greatly regulated genes with immunofluorescent staining revealed an increased expression of gephyrin in the ipsilateral S1 after TNI was decreased by EA; while TNI-induced increases in Tomm20, a biomarker of mitochondria, in the contralateral ACC were further enhanced after EA. We concluded that neuropathic pain is associated with differential epigenetic regulations of gene expression in the ACC and S1 and that the analgesic effect of EA may involve regulating cortical gene expression.
13 March 2018 in CNS & Neurological Disorders - Drug Targets
6-[(1S)-1-[1-[5-(2-hydroxyethoxy)-2-pyridyl]pyrazol-3-yl]ethyl]-3H-1,3-benzothiazol-2-one (LY3130481 or CERC-611) is a selective antagonist of AMPA receptors containing transmembrane AMPA receptor regulatory protein (TARP) g-8 that is under development for epilepsy. The present study provided a broad inquiry into its anticonvulsant properties. LY3130481 was anticonvulsant in multiple acute seizure provocation models in mice and rats. In addition, LY3130481 was effective against absence seizures in the GAERS genetic model and in the Frings mouse model. Likewise LY3130481 attenuated convulsions in mice and rats with long term induction of seizures (e.g., corneal, pentylenetetrazole, hippocampal, and amygdala kindled seizures). In slices of epileptic human cortex, LY3130481 significantly decreased neuronal firing frequencies. LY3130481 displaced from rat brain a radioligand specific for AMPA receptors associated with TARP g-8 whereas non-TARP-selective molecules did not. Binding was also observed in hippocampus freshly transected from a patient Taken as a whole, the findings reported here establish the broad anticonvulsant efficacy of LY3130481 indicating that blockade of AMPA receptors associated with TARP g-8 is sufficient for these protective effects.