Extracellular microRNA 130b-3p inhibits eCIRP-induced inflammation

Area of Science:

• Molecular Biology
• Immunology
• Biochemistry

Background:

• MicroRNAs regulate gene expression intracellularly but are released into circulation during inflammation.
• Extracellular cold-inducible RNA-binding protein (eCIRP) acts as a damage-associated molecular pattern (DAMP) in sepsis, promoting inflammation and tissue damage.
• Sepsis involves complex inflammatory responses, necessitating the identification of endogenous regulatory mechanisms.

Purpose of the Study:

• To investigate the role of circulating microRNA 130b-3p in regulating eCIRP-mediated inflammation.
• To determine if miR-130b-3p can serve as an endogenous inhibitor of eCIRP.
• To explore the therapeutic potential of miR-130b-3p in sepsis and related inflammatory conditions.

Main Methods:

• Quantification of serum miR-130b-3p levels in septic mice and patients.
• In vitro and in vivo interaction studies between miR-130b-3p and eCIRP.
• Macrophage stimulation assays to assess TNF-α release.
• Analysis of eCIRP-TLR4/MD2 receptor binding affinity.
• In vivo studies using miR-130b-3p mimics in mouse models of sepsis and acute lung injury.

Main Results:

• Serum levels of miR-130b-3p were elevated in septic conditions.
• miR-130b-3p directly interacted with eCIRP in vitro and in vivo.
• miR-130b-3p mimic co-treatment reduced TNF-α release from macrophages and decreased eCIRP binding to TLR4/MD2.
• Administration of miR-130b-3p mimic ameliorated systemic inflammation and acute lung injury in mouse models.

Conclusions:

• Extracellular miR-130b-3p acts as a novel endogenous inhibitor of eCIRP.
• miR-130b-3p attenuates both sterile and non-sterile inflammatory responses mediated by eCIRP.
• miR-130b-3p represents a promising therapeutic target for managing inflammatory diseases like sepsis.