DNMT3a‐triggered downregulation of K_2p1.1 gene in primary sensory neurons contributes to paclitaxel‐induced neuropathic pain

Abstract

Antineoplastic drugs induce dramatic transcriptional changes in dorsal root ganglion (DRG) neurons, which may contribute to chemotherapy‐induced neuropathic pain. K2p1.1 controls neuronal excitability by setting the resting membrane potential. Here, we report that systemic injection of the chemotherapy agent paclitaxel time‐dependently downregulates the expression of K 2p1.1 mRNA and its coding K2p1.1 protein in the DRG neurons. Rescuing this downregulation mitigates the development and maintenance of paclitaxel‐induced mechanical allodynia and heat hyperalgesia. Conversely, in the absence of paclitaxel administration, mimicking this downregulation decreases outward potassium current and increases excitability in the DRG neurons, leading to the enhanced responses to mechanical and heat stimuli. Mechanically, the downregulation of DRG K 2p1.1 mRNA is attributed to paclitaxel‐induced increase in DRG DNMT3a, as blocking this increase reverses the paclitaxel‐induced the decrease of DRG K2p1.1 and mimicking this increase reduces DRG K2p1.1 expression. In addition, paclitaxel injection increases the binding of DNMT3a to the K 2p1.1 gene promoter region and elevates the level of DNA methylation within this region in the DRG. These findings suggest that DNMT3a‐triggered downregulation of DRG K2p1.1 may contribute to chemotherapy‐induced neuropathic pain.

Fgr contributes to hemorrhage-induced thalamic pain by activating NF-κB/ERK1/2 pathways

“…RNA extraction and real-time reverse transcription PCR assays were carried out as described previously ( 48 ). Briefly, total RNA was extracted by the TRIzol method (Invitrogen, Thermo Fisher Scientific Inc.), treated with DNase (New England Biolabs), and reverse-transcribed using ThermoScript reverse transcriptase (Invitrogen, Thermo Fisher Scientific Inc.) and oligo (dT) primers (Invitrogen, Thermo Fisher Scientific Inc.).…”

Long noncoding RNA MEG3 suppresses podocyte injury in diabetic nephropathy by inactivating Wnt/β-catenin signaling

“…The TurboFect in vivo transfection reagent (Thermo Scientific, Wilmington, NC, USA) was used as an in vivo delivery vehicle for pcDNA3-MEG3 to prevent degradation and enhance transfection efficiency as described previously (Mao et al, 2019; Xu et al, 2014).…”

Contribution of DNMT1 to Neuropathic Pain Genesis Partially through Epigenetically Repressing Kcna2 in Primary Afferent Neurons

“…Control experiments for rabbit anti-DNMT1 included substitution of normal rabbit serum for the primary antiserum, omission of the primary antiserum, and preabsorption of the primary antibody with overdose of the antigen. The specificity of remaining primary antisera has been identified previously Shao et al, 2017;Sun et al, 2017;Xu et al, 2017;Zhao et al, 2017;Mo et al, 2018;Mao et al, 2019;Yuan et al, 2019). The sections finally mounted using VectaMount permanent mounting medium (Vector Laboratories) or Vectashield plus DAPI mounting medium (Vector Laboratories).…”

“…The specificity of rabbit anti-DNMT1 was examined in the following control experiments, including substitution of normal rabbit serum for the primary antiserum, omission of the primary antiserum, and preabsorption of the primary antibody with overdose of the antigen. The specificity of remaining primary antisera was reported previously (Lee et al, 2011;Zhao et al, 2013Zhao et al, , 2017Fan et al, 2014;Li et al, 2015Sun et al, 2017;Mo et al, 2018;Du et al, 2019;Mao et al, 2019) or from vendors' data sheets. Membranes were further incubated with anti-mouse or anti-rabbit HRP-conjugated secondary antibody (1: 3000, Jackson ImmunoResearch Laboratories) for 2 h at room temperature and visualized by Western peroxide reagent and luminol/enhancer reagent (Clarity Western ECL Substrate, Bio-Rad).…”

“…Conventionally, DNMT3a and DNMT3b function as de novo DNMTs to revers-ibly methylate unmethylated DNA, whereas DNMT1 is classified as the primary DNMT to maintain DNA methylation that has been established at the genome (Jeltsch, 2006;Siedlecki and Zielenkiewicz, 2006). The contribution of de novo DNMT3atriggered DNA methylation to neuropathic pain genesis was reported Shao et al, 2017;Sun et al, 2017;Zhao et al, 2017;Mo et al, 2018;Mao et al, 2019;Yuan et al, 2019). Expression of DNMT3a, but not DNMT3b, is increased in the injured DRG following peripheral nerve injury .…”