Evidence map›Paper›PMID 42549977›Full record

ArticleEuropean journal of pain (London, England)2026

SARS-CoV-2 Spike Peptides Trigger Nociceptive Responses Through Spinal TLR4 Pathways.

Bruno Eduardo Silva, Rayner Ribeiro Cardoso, Lívia Maria Ribeiro Rosário, João Paulo Prado, Rafaela Silva Dos Santos, Flávio Protasio Veras, Mylena de Souza, Eduardo Maffud Cilli, Danilo Olivier, Marco Antonio de Andrade Belo and 6 more

Abstract read
In one paragraph

Article in European journal of pain (London, England), 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

0numbers the graph read from it
0cells of the map it votes in
0citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

0 citing papers in PubMed.

No citing paper in PubMed yet.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

16 authors.

Bruno Eduardo SilvaLaboratory of Neuroimmunobiology of Pain, Center for Experimental Biology, Federal University of Alfenas, Alfenas, Minas Gerais, Brazil.
Rayner Ribeiro CardosoLaboratory of Neuroimmunobiology of Pain, Center for Experimental Biology, Federal University of Alfenas, Alfenas, Minas Gerais, Brazil.
Lívia Maria Ribeiro RosárioLaboratory of Neuroimmunobiology of Pain, Center for Experimental Biology, Federal University of Alfenas, Alfenas, Minas Gerais, Brazil.
João Paulo PradoLaboratory of Neuroimmunobiology of Pain, Center for Experimental Biology, Federal University of Alfenas, Alfenas, Minas Gerais, Brazil.
Rafaela Silva Dos SantosLaboratory of Neuroimmunobiology of Pain, Center for Experimental Biology, Federal University of Alfenas, Alfenas, Minas Gerais, Brazil.
Flávio Protasio VerasLaboratory of Neuroimmunobiology of Pain, Center for Experimental Biology, Federal University of Alfenas, Alfenas, Minas Gerais, Brazil.
Mylena de SouzaLaboratory of Neuroimmunobiology of Pain, Center for Experimental Biology, Federal University of Alfenas, Alfenas, Minas Gerais, Brazil.
Eduardo Maffud CilliUnesp - Institute of Chemistry - Araraquara Campus, Sao Paulo, Brazil.
Danilo OlivierDepartment of Physics and Interdisciplinary Technologies, Federal University of Northern Tocantins, Araguaína, Brazil.
Marco Antonio de Andrade BeloBrasil University, Descalvado, Sao Paulo, Brazil.
Ives Charlie-SilvaUnesp - Institute of Chemistry - Araraquara Campus, Sao Paulo, Brazil.
Ester Siqueira CaixetaDepartment of Cellular and Developmental Biology, Federal University of Alfenas, Alfenas, Minas Gerais, Brazil.
Angel Roberto BarchukInsect Molecular Biology Laboratory, Federal University of Alfenas, Alfenas, Minas Gerais, Brazil.
Albená Nunes-SilvaInflammation and Exercise Immunology Laboratory, Federal University of Ouro Preto, Physical Education School, Ouro Preto, Minas Gerais, Brazil.
Thiago Roberto Lima RomeroLaboratory of Pain and Analgesia, Pharmacology Department, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
Giovane GaldinoLaboratory of Neuroimmunobiology of Pain, Center for Experimental Biology, Federal University of Alfenas, Alfenas, Minas Gerais, Brazil.ORCID https://orcid.org/0000-0002-1898-1973

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

backgroundPain is a common neurological manifestation of COVID-19, yet the mechanisms by which SARS-CoV-2 spike protein fragments contribute to nociceptive processing remain poorly understood. We investigated whether spike-derived peptides directly activate spinal neuroimmune pathways involved in pain signalling.

methodsMale C57BL/6 mice received intrathecal administration of three synthetic SARS-CoV-2 spike-derived peptides (PSPD2001, PSPD2002 or PSPD2003) or saline. Mechanical nociception was assessed using the von Frey test. The involvement of spinal Toll-like receptor 4 (TLR4), microglia and p38 MAPK/NF-κB signalling was investigated using pharmacological antagonists, TLR4 knockout mice, RT-qPCR, ELISA, immunofluorescence, CX3CR1

resultsAll spike-derived peptides induced mechanical nociception, with PSPD2003 producing the most pronounced response. PSPD2003 increased spinal TLR4 expression, elevated TNF-α and IL-6 levels and promoted activation of dorsal horn microglia, demonstrated by increased TMEM119- and CX3CR1-positive cells. These nociceptive and neuroinflammatory effects were abolished by pharmacological inhibition of TLR4, microglia, p38 MAPK and NF-κB signalling, as well as in TLR4

conclusionsThese findings identify a previously unrecognized neuroimmune mechanism whereby a SARS-CoV-2 spike-derived peptide triggers spinal nociception through TLR4-dependent microglial activation and downstream p38 MAPK/NF-κB signalling, highlighting the spinal TLR4-microglia axis as a potential therapeutic target for COVID-19-associated and post-viral pain. SIGNIFICANCE STATEMENT: This study provides the first evidence that SARS-CoV-2 spike-derived peptides directly activate a spinal TLR4-dependent neuroimmune pathway to induce nociception. By integrating behavioural, pharmacological, genetic, cellular and computational approaches, it identifies microglial activation and p38 MAPK/NF-κB signalling as key mechanisms linking viral peptides to pain, providing a mechanistic framework for COVID-19- and post-viral pain and supporting TLR4 as a potential therapeutic target.

Indexed as

COVID-19NociceptionSpike Glycoprotein, CoronavirusSpinal CordToll-Like Receptor 4AnimalsHumansMaleMiceMice, Inbred C57BLMice, KnockoutMicrogliaNF-kappa Bp38 Mitogen-Activated Protein KinasesSARS-CoV-2Signal TransductionNF-kappa Bp38 Mitogen-Activated Protein KinasesSpike Glycoprotein, Coronavirusspike protein, SARS-CoV-2Tlr4 protein, mouseToll-Like Receptor 4cytokinesmicrogliapainspike proteintoll‐like 4 receptors

Identifiers

PMID42549977
PMCPMC13435826

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.