LncRNA ZNF883-Mediated NLRP3 Inflammasome Activation and Epilepsy Development Involve USP47 Upregulation

Mol Neurobiol. 2022 Aug;59(8):5207-5221. doi: 10.1007/s12035-022-02902-7. Epub 2022 Jun 9.

Abstract

The goal of this study was to characterize the mechanisms of long noncoding RNA (lncRNA) ZNF883 regulating NOD-like receptor 3 (NLRP3) inflammasome activation in epilepsy (EP). Rat and cellular EP models were established using pilocarpine and magnesium-free extracellular fluid, respectively, to detect the differential expression of ZNF883, microRNA (miR)-138-5p, ubiquitin-specific peptidase 47 (USP47), and NLRP3. The pathology of the hippocampal neurons was examined by whole-cell patch clamping. The expression of ZNF883, miR-138-5p, and USP47 was modified in epileptic neurons, and the EP rats were injected with sh-ZNF883. Then, alterations in ZNF883, miR-138-5p, and USP47 levels were measured. The histopathology of the hippocampus was detected, along with the detection of IL-6, IL-1β, TNF-α, and NLRP3. Neuronal apoptosis in the rat and cellular EP models was determined. The relationship among ZNF883, miR-138-5p, and USP47 as well as the regulation of NLRP3 ubiquitination by USP47 was determined. ZNF883, USP47, and NLRP3 were increasingly expressed and miR-138-5p was downregulated in epileptic neurons and rats, concurrent with aggravated inflammation and apoptosis. ZNF883 overexpression in epileptic neurons elevated USP47 expression. ZNF883 targeted miR-138-5p and miR-138-5p negatively regulated USP47. In epileptic neurons, inhibiting miR-138-5p or overexpressing USP47 partially reversed the ZNF883 silencing-induced inhibition on NLRP3 inflammasome activation, neuronal apoptosis, and epileptiform activity. ZNF883 silencing in EP rats decreased USP47 and NLRP3, increased miR-138-5p, and inhibited inflammation and apoptosis. USP47 reversed the ubiquitination of NLRP3. ZNF883 inhibits NLRP3 ubiquitination and promotes EP through upregulating USP47 by sponging miR-138-5p.

Keywords: Epilepsy; Long noncoding RNA ZNF883; NLRP3; USP47; Ubiquitination; miR-138-5p.

MeSH terms

  • Animals
  • Apoptosis / genetics
  • Epilepsy* / genetics
  • Inflammasomes / metabolism
  • Inflammation
  • MicroRNAs* / genetics
  • MicroRNAs* / metabolism
  • NLR Family, Pyrin Domain-Containing 3 Protein / genetics
  • NLR Family, Pyrin Domain-Containing 3 Protein / metabolism
  • NLR Proteins / genetics
  • NLR Proteins / metabolism
  • RNA, Long Noncoding* / genetics
  • RNA, Long Noncoding* / metabolism
  • Rats
  • Ubiquitin Thiolesterase* / metabolism
  • Ubiquitin-Specific Proteases* / metabolism
  • Up-Regulation / genetics

Substances

  • Inflammasomes
  • MicroRNAs
  • MIRN138 microRNA, rat
  • NLR Family, Pyrin Domain-Containing 3 Protein
  • NLR Proteins
  • Nlrp3 protein, rat
  • RNA, Long Noncoding
  • Ubiquitin Thiolesterase
  • Ubiquitin-Specific Proteases
  • Usp47 protein, rat