miR-155 Aggravates Liver Ischemia/reperfusion Injury by Suppressing SOCS1 in Mice

Area of Science:

• Hepatology
• Immunology
• Molecular Biology

Background:

• Liver ischemia/reperfusion injury (IRI) is a significant clinical problem during liver surgery and transplantation.
• Toll-like receptor (TLR) activation by inflammatory cytokines is a key mediator of liver IRI.
• The role of microRNA-155 (miR-155) in liver IRI is not well understood.

Purpose of the Study:

• To investigate the role of miR-155 in liver IRI.
• To elucidate the molecular mechanisms by which miR-155 affects liver injury.

Main Methods:

• Upregulation of miR-155 expression was assessed during liver I/R in vivo and in vitro.
• The effect of forced miR-155 expression on hepatocyte injury was evaluated.
• Mice were transfected with a modified miR-155 inhibitor (Ago-miR-155) to assess its protective effects.
• Expression levels of miR-155 target gene SOCS1, NF-κB activation, and pro-inflammatory cytokines (TNF-α, IL-6) were measured.

Main Results:

• miR-155 expression was significantly upregulated during liver I/R.
• Forced expression of miR-155 exacerbated liver injury both in vivo and in vitro.
• Inhibition of miR-155 using Ago-miR-155 reduced liver injury severity.
• miR-155 was found to inhibit the expression of SOCS1, leading to increased NF-κB activation and elevated production of TNF-α and IL-6.

Conclusions:

• miR-155 plays a detrimental role in liver IRI.
• Overexpression of miR-155 aggravates liver injury by suppressing SOCS1, which promotes NF-κB activation and subsequent inflammation.
• Targeting miR-155 may represent a therapeutic strategy for mitigating liver I/R injury.