The Functional Roles of RNAs Cargoes Released by Neutrophil-Derived Exosomes in Dermatomyositis.

Liya Li,Honglin Zhu,Di Liu,Hui Luo,Xiaoxia Zuo

doi:10.3389/fphar.2021.727901

Abstract

Dermatomyositis (DM) is an idiopathic inflammatory myopathy characterized by cutaneous manifestations. We first identified the profiles of noncoding RNAs (lncRNAs and miRNAs) in peripheral neutrophil exosomes (EXOs) of DM patients and explored their potential functional roles. Bioinformatics analyses were performed with R packages. Real-time quantitative PCR was used to validate the altered RNAs in DM neutrophil EXO-stimulated human dermal microvascular endothelial cells (HDMECs) and human skeletal muscle myoblasts (HSkMCs). In DM neutrophil EXOs, 124 upregulated lncRNAs (with 1,392 target genes), 255 downregulated lncRNAs (with 1867 target genes), 17 upregulated miRNAs (with 2,908 target genes), and 15 downregulated miRNAs (with 2,176 target genes) were identified. GO analysis showed that the differentially expressed (DE) lncRNAs and DE miRNAs participated in interleukin-6 and interferon-beta production, skeletal muscle cell proliferation and development, and endothelial cell development and differentiation. KEGG analysis suggested that DE lncRNAs and DE miRNAs were enriched in the PI3K–Akt, MAPK, AMPK and FoxO signalling pathways. Many novel and valuable DE lncRNAs and DE miRNAs interacted and cotargeted in the PI3K–Akt, MAPK, AMPK and FoxO signalling pathways. Our study suggests that neutrophil EXOs participate in DM pathogenesis through lncRNAs and miRNAs in the PI3K–Akt, MAPK, AMPK and FoxO signalling pathways.

Highlights

Dermatomyositis (DM) is an idiopathic inflammatory myopathy with characteristic cutaneous manifestations and symmetrical progressive proximal weakness (Bohan and Peter, 1975a; Bohan and Peter, 1975b; Callen, 2000)
We identified 379 differentially expressed (DE) long noncoding RNAs (lncRNAs) in neutrophil EXOs in DM patients compared with normal controls (NCs), including 124 upregulated and 255 downregulated lncRNAs [Supplementary Data S1]
Gene Ontology (GO) analysis of these target genes revealed that the regulation of interleukin-6 production, IFN-β production and skeletal muscle cell proliferation terms were enriched; Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis indicated that the Forkhead box O (FoxO) signalling pathway, endocytosis and JAK-STAT signalling pathway were involved (Table 3 and Supplementary Tables S7, S8)

Summary

Introduction

Dermatomyositis (DM) is an idiopathic inflammatory myopathy with characteristic cutaneous manifestations and symmetrical progressive proximal weakness (Bohan and Peter, 1975a; Bohan and Peter, 1975b; Callen, 2000). The hallmark histopathological features of DM include perifascicular atrophy and inflammatory infiltration (by macrophages/neutrophils, CD20+ B cells, CD4+ T cells and plasmacytoid dendritic cells) in muscle (Dalakas, 2015; DeWane et al, 2019). Neutrophils interact with macrophages, dendritic cells, B and T cells, and natural killer cells that produce IFN-γ, regulating the immune response (Jaillon et al, 2013). Proteinases and proteins in the neutrophil cytoplasm were found to play important roles in muscle inflammatory cell infiltration and vascular damage in DM patients (Gao et al, 2018b; Xiao et al, 2019). All of the above results suggest that neutrophils play important roles in the pathogenesis of DM; the detailed mechanisms need further research

Methods

Results

Conclusion