lncRNA MEG3 aggravated neuropathic pain and astrocyte overaction through mediating miR-130a-5p/CXCL12/CXCR4 axis

Aging (Albany NY). 2021 Oct 5;13(19):23004-23019. doi: 10.18632/aging.203592. Epub 2021 Oct 5.

Abstract

Objective: Long non-coding RNAs (lncRNAs) exert a critical function in mediating neuropathic pain (NP). MEG3, a novel lncRNA, contributes to astrocyte activation and inflammation. However, its role in NP remains unclear.

Methods: The chronic constriction injury (CCI) method was employed to construct an NP rat model. Astrocyte activation was induced by lipopolysaccharide (LPS). The profiles of MEG3, microRNA (miR)-130a-5p, CXC motif chemokine receptor 12 (CXCL12)/CXC motif chemokine receptor 4 (CXCR4), and the Rac1/NF-κB pathway in CCI rats' spinal cord tissues and astrocytes were monitored by reverse transcription-quantitative PCR (RT-qPCR) and western blot (WB). Pain scores of CCI rats were assessed. Enzyme-linked immunosorbent assay (ELISA) was adopted to monitor neuroinflammation alteration. The glial fibrillary acidic protein (GFAP)-labeled astrocytes were tested by immunohistochemistry (IHC). Bioinformatics, dual-luciferase reporter assay and RNA immunoprecipitation (RIP) were utilized to verify the molecular mechanism between MEG3 and miR-130a-3p.

Results: MEG3, CXCL12 and CXCR4 were overexpressed and miR-130a-5p was knocked down in CCI rats and LPS-induced astrocytes. Up-regulating MEG3 aggravated NP, enhanced inflammatory cytokines interleukin-1β (IL-1β), tumor necrosis factor (TNF)-α, and interleukin-6 (IL-6) expression and release in CCI rats and LPS-induced astrocytes. Up-regulating miR-130-5p repressed LPS-induced inflammation in astrocytes. AS verified by the dual-luciferase reporter assay and RIP assay, MEG3 sponged miR-130a-5p as a competitive endogenous RNA (ceRNA). What's more, miR-130a-5p up-regulation weakened the MEG3-induced proinflammatory effects on LPS-induced astrocytes.

Conclusions: MEG3 aggravates NP and astrocyte activation via the miR-130a-5p/CXCL12/CXCR4 axis, which is a potential therapeutic target for NP.

Keywords: CXCL12; MEG3; astrocytes; miR-130a-5p; neuropathic pain.

MeSH terms

  • Animals
  • Astrocytes / cytology
  • Astrocytes / metabolism
  • Cells, Cultured
  • Chemokine CXCL12 / genetics*
  • Chemokine CXCL12 / metabolism
  • Female
  • Humans
  • MicroRNAs / genetics*
  • MicroRNAs / metabolism
  • Neuralgia / metabolism*
  • RNA, Long Noncoding / genetics*
  • RNA, Long Noncoding / metabolism
  • Rats
  • Rats, Sprague-Dawley
  • Receptors, CXCR4 / genetics*
  • Receptors, CXCR4 / metabolism

Substances

  • CXCL12 protein, rat
  • Chemokine CXCL12
  • Cxcr4 protein, rat
  • MEG3 non-coding RNA, rat
  • MIRN130 microRNA, rat
  • MicroRNAs
  • RNA, Long Noncoding
  • Receptors, CXCR4