Search

Pyroptosis is defined as inflammation-induced programmed cell death. However, gene expression levels related to pyroptosis and their role in neuropathic pain (NP) remain unclear. The present study aimed to develop and validate an NP-predictive signature based on the genes associated with pyroptosis. Gene expression level profiles were downloaded from the Gene Expression Omnibus database. Weighted gene co-expression network analysis was used to identify the pyroptotic genes most highly associated with NP. NP-related pyroptosis gene signature was constructed using multivariate logistic regression. A rat model of neuropathic pain was established through chronic constriction injury to analyse the inflammatory infiltration and myelin damage around the sciatic nerve, and examine the expression levels of macrophage markers S100 calcium-binding protein β (S100β) and ionized calcium-binding adapter molecule 1 (Iba-1). Finally, flow cytometry analysis was used to examine the lipopolysaccharide (LPS)-induced cell death ratio of RSC96 cells (Schwann cells), while the expression levels of LPS-induced pyroptosis-related genes in RSC96 cells were measured via reverse transcription-quantitative PCR. The results demonstrated that pyroptosis-related genes (gasdermin D, NLR family pyrin domain containing 3, neuronal apoptosis inhibitory protein and NLR family CARD domain containing 4) were identified to increase the risk of NP. NP-related pyroptosis signatures were constructed based on these four genes. Moreover, the high-risk group had a higher level of macrophage infiltration compared with the low-risk group, as determined by the CIBERSORT algorithm. H&E staining results showed that the myelin structure of the sciatic nerve tissue of chronic constriction injury (CCI) rats was destroyed and inflammatory cells infiltrated around neurons. The results of immunohistochemistry showed that compared with in the sham group, the expression levels of Iba-1 and sS100β in the sciatic nerve of the CCI group were increased. Furthermore, the expression levels of cell death and pyroptosis-related genes in Schwann cells induced by LPS were increased compared with in the control group. In conclusion, an NP-related pyroptosis gene signature was constructed based on four pyroptosis-related genes and it was found that the expression of pyroptosis-related genes was upregulated in the early steps of the neuroinflammatory process in RSC96 cells. [ABSTRACT FROM AUTHOR]

Late-stage carotid atherosclerosis has a high incidence rate and may lead to various cerebrovascular diseases. The gene expression profile GSE100927 was selected to identify differentially expressed genes (DEGs) in carotid atherosclerosis. Subsequently, protein-protein interaction, Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses were conducted. Furthermore, experimental verification was performed using human umbilical vein endothelial cells (HUVECs), human aortic vascular smooth muscle cells (HAVSMCs) and Tohoku Hospital Pediatrics-1 (THP-1)-induced macrophages. The groups were as follows: Control group, solvent control group and palmitic acid group. The levels of reactive oxygen species (ROS) in the three cell types were detected by flow cytometry or fluorescence microscopy. Furthermore, apoptosis of HUVECs and HAVSMCs was assessed by flow cytometry and the nuclear Hoechst 33258 staining of THP-1-induced macrophages was performed. Male late-stage carotid atherosclerosis samples, including 10 control samples and 21 atherosclerosis samples, were selected. Pathway enrichment analysis demonstrated that 'Toll-like receptor signaling pathway' was the top pathway associated with the DEGs. MMP7, MMP9, IL1β, C-C motif chemokine ligand 4 (CCL4), secreted phosphoprotein 1 (SPP1), CCL3 and interferon regulatory factor 5 (IRF5) were selected for experimental verification. Palmitic acid increased the ROS levels and the apoptosis rates of HUVECs and HAVSMCs. However, it did not increase the levels of ROS and did not shrink the nuclei of THP-1-induced macrophages. Furthermore, palmitic acid increased the mRNA levels of IL1β, CCL4, SPP1, CCL3, IRF5, MMP7 and MMP9 in HUVECs and THP-1-induced macrophages, and increased the mRNA levels of CCL4 and MMP9 in HAVSMCs. In conclusion, IL1β, CCL3, CCL4, SPP1, IRF5, MMP7 and MMP9 are important markers of late-stage carotid atherosclerosis. [ABSTRACT FROM AUTHOR]