Interplay between Intravitreal RvD1 and Local Endogenous Sirtuin-1 in the Protection from Endotoxin-Induced Uveitis...

Area of Science:

• Ophthalmology
• Immunology
• Pharmacology

Background:

• Endotoxin-induced uveitis (EIU) in rats serves as a key model for human uveitis.
• Resolvin D1 (RvD1) is a pro-resolving mediator with potential anti-inflammatory properties.
• Sirtuin-1 (SIRT1) is a deacetylase involved in cellular regulation and inflammation.

Purpose of the Study:

• To investigate the protective effects of RvD1 in a rat model of EIU.
• To elucidate the molecular mechanisms underlying RvD1's action, focusing on SIRT1.
• To explore the role of specific microRNAs and signaling pathways in RvD1-mediated EIU resolution.

Main Methods:

• EIU was induced in Sprague-Dawley rats via subcutaneous lipopolysaccharide (LPS) injection.
• Intravitreal RvD1 administration was performed at varying doses (10-1000 ng/kg).
• SIRT1 activity was modulated using the specific inhibitor EX527; formyl-peptide receptor 2 (FPR2) was blocked with Boc2.

Main Results:

• RvD1 significantly prevented EIU development in a dose-dependent manner.
• RvD1 increased ocular SIRT1 expression and decreased acetylated p53 and FOXO1.
• RvD1 modulated specific microRNAs (miR-195-5p, miR-200a-3p, miR-34a-5p, miR-145-5p) and altered manganese superoxide dismutase and caspase 3 levels.

Conclusions:

• RvD1 demonstrates significant therapeutic potential for EIU by modulating SIRT1.
• The protective effects of RvD1 are partly mediated through SIRT1 activation and potentially FPR2.
• RvD1's mechanism involves regulating key inflammatory and apoptotic pathways within the eye.