bioRxiv Science⌕ Search

bioRxiv · 10.1101/2022.06.20.496565

Pregabalin silences oxaliplatin-activated sensory neurons to relieve cold allodynia

Abstract

Oxaliplatin is a platinum-based chemotherapeutic agent that causes cold and mechanical allodynia in up to 90% of patients. Silent NaV1.8-positive nociceptive cold sensors have been shown to be unmasked by oxaliplatin and other neuropathic insults. This event has been causally linked to the development of cold and mechanical allodynia. Pregabalin is an anti-epileptic and analgesic drug that acts through a calcium channel 2{delta}-1 subunit to lower neurotransmitter release. Recent data also suggest pregabalin can act on NMDA receptors and other proteins, but the site of analgesic action has been considered to be the central nervous system. We examined the effects of pregabalin on oxaliplatin-evoked unmasking of cold sensitive neurons using mice expressing GCaMP-3 driven by a Pirt promoter in all sensory neurons. We found that in mice treated with oxaliplatin, intravenous injection of pregabalin significantly decreased cold allodynia. Interestingly, pregabalin also decreased the number of sensory neurons responding to cold nociceptive stimuli by altering their excitability and their temperature thresholds. These silenced neurons are medium/large cells responding to both painful mechanical and cold stimuli, corresponding to the "silent" cold sensors that become active in numerous neuropathic pain models. Deletion of 2{delta}-1 subunits abolished the effects of pregabalin on both cold allodynia and the silencing of sensory neuron unmasked by oxaliplatin. Taken together, these results define a novel, peripheral inhibitory effect of pregabalin on the excitability of silent cold-sensing neurons in a model of oxaliplatin-dependent cold allodynia. Abbreviated SummaryIseppon et al. report a novel, peripheral effect of pregabalin on oxaliplatin-dependent cold allodynia. The drug exerts its effect by silencing a specific sub-population of neurons responding to cold and mechanical stimuli in the dorsal root ganglion, and this effect is dependent on the 2{delta}-1 subunit of voltage-gated calcium channels.

Source connections

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Iseppon, F., Luiz, A. P., Linley, J. E., Wood, J. N.. 2022-06-20. Pregabalin silences oxaliplatin-activated sensory neurons to relieve cold allodynia. https://doi.org/10.1101/2022.06.20.496565

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related preprints

The Unreasonable Effectiveness of Cell Types in Describing Neuronal Physiological Features

Single-cell RNA sequencing (scRNA-seq) captures detailed gene expression profiles at scale, while patch-clamp recordings measure intrinsic neuronal electrophysiological properties. Modeling the relations between these two modalities remains a challenge. Here, we compare how well electrophysiological features can be predicted by traditional transcriptomic cell type classification, representations derived from a foundational model (scGPT) pretrained on large-scale scRNA-seq datasets, ion channel-coding genes, and highly variable genes. Using paired transcriptomic and electrophysiological patch-sequencing data from 495 human neurons from neurosurgical tissue, we find that cluster-level cell type representations consistently outperform highly variable gene selection, ion channel gene selection, and context-enriched scGPT embeddings. Notably, performance varies across model architectures and initializations, and the best results are obtained by combining the outputs of separate cell type and scGPT-based models. Together, these findings suggest that traditional discrete cellular classification is highly effective in predicting physiological features. For maximum performance it can be complemented by pretrained transformer models.

neuroscience↗

A nonlinear inhibition pathway underlying cortical responses to tuned holographic optogenetic perturbations

Optogenetics enables causal manipulation of cortical activity. Perturbation responses can be counterintuitive due to network interactions, making theory essential for predicting them. Existing approaches often rely on linear approximations, which fail for many biologically relevant perturbations. Here we develop a nonlinear theory of responses to holographic perturbations in cell-type-specific recurrent networks with structured connectivity. We fit a nonlinear model to mouse V1 data, which shows cotuned-ensemble suppression: perturbing spatially clustered neurons with similar preferred orientations yields markedly stronger short-range suppression than perturbing untuned ensembles. We show that cotuned-ensemble suppression arises from a feature-tuned, nonlinear inhibition pathway implicating somatostatin-positive (SST) interneurons. The theory predicts that cotuned ensembles suppress parvalbumin-positive (PV) neurons but facilitate SST neurons, and links the degree of cotuned-ensemble suppression or facilitation to the variance of the SST response. This framework identifies mechanisms by which nonlinear inhibition sculpts cortical dynamics and establishes a predictive basis for targeted optogenetic interventions.

neuroscience↗

Proteomic signatures of APOE ε4 across human tissues and cell types in Alzheimers disease

The apolipoprotein E {varepsilon}4 (APOE {varepsilon}4) allele is the strongest genetic risk factor for late-onset Alzheimers disease (AD). However, the underlying molecular mechanisms remain unclear. This study included 1691 participants from the Religious Orders Study and Rush Memory and Aging Project (ROSMAP), 1226 participants from the Accelerating Medicines Partnership - Alzheimers Disease (AMP-AD) Diverse Cohorts Study, and 735 participants from the Alzheimers Disease Neuroimaging Initiative (ADNI). To characterise APOE {varepsilon}4 molecular effects, we analysed proteomic data from plasma, cerebrospinal fluid (CSF), and induced pluripotent stem cell (iPSC)-derived astrocytes and neurons, as well as transcriptomic and proteomic data from multiple brain regions. The association of APOE {varepsilon}4 with AD neuropathology was also examined. APOE {varepsilon}4 carriers shared a plasma proteomic signature enriched for immune processes, irrespective of AD diagnosis. A machine learning classifier trained on this signature discriminated APOE {varepsilon}4 carriers from non-carriers in an independent cohort using CSF proteomics. APOE {varepsilon}4 carriage was associated with higher Braak stages and Consortium to Establish a Registry for Alzheimers Disease (CERAD) score. However, only limited APOE {varepsilon}4-associated transcriptomic and proteomic changes were observed in bulk brain tissue, with poor cross-layer concordance. Proteomic analyses of iPSC-derived astrocytes and neurons further revealed cell-type-specific APOE {varepsilon}4-associated changes. APOE {varepsilon}4 is associated with a consistent proteomic signature across plasma and CSF. Its molecular effects in the brain differ across cell types, brain regions and molecular layers. These findings support the need for cell-type-resolved multi-omic studies to elucidate how APOE {varepsilon}4 confers AD risk.

neuroscience↗