Synthesis of Lipidated Ligands and Formulation of Glia-Specific LNPs for RNAi-Mediated BBB Protection

J Med Chem. 2024 Aug 8;67(15):13217-13230. doi: 10.1021/acs.jmedchem.4c01176. Epub 2024 Jul 20.

Abstract

Pro-inflammatory polarization of microglia and astrocytes results in neuroinflammation and blood-brain barrier (BBB) disruption after a primary traumatic brain injury (TBI). Herein, we demonstrate that the dual-ligand functionalized lipid nanoparticles (AM31 LNPs) were actively and specifically internalized by microglia and astrocytes via mannose receptor (MR)- and adenosine receptor (AR)-mediated endocytosis, respectively, in a mouse model of TBI. Systemic administration of AM31 LNPs carrying siRNA against p65 resulted in internalization by the glial cells in the peri-infarct region and a robust knockdown of p65 at both mRNA and protein levels in these cells, leading to significant down-regulation of key pro-inflammatory cytokines and up-regulation of key anti-inflammatory cytokines. AM31 LNP-mediated silencing of p65 ameliorated TBI-induced BBB disruption. Our data proved that AM 31 LNP is a promising vehicle for RNA therapeutics for targeting microglia and astrocytes in neural disorder.

MeSH terms

  • Animals
  • Astrocytes / drug effects
  • Astrocytes / metabolism
  • Blood-Brain Barrier* / metabolism
  • Brain Injuries, Traumatic / drug therapy
  • Brain Injuries, Traumatic / metabolism
  • Brain Injuries, Traumatic / pathology
  • Brain Injuries, Traumatic / therapy
  • Ligands
  • Lipids* / chemistry
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Microglia / drug effects
  • Microglia / metabolism
  • Nanoparticles* / chemistry
  • Neuroglia / drug effects
  • Neuroglia / metabolism
  • RNA Interference
  • RNA, Small Interfering / metabolism

Substances

  • Ligands
  • Lipids
  • RNA, Small Interfering