Vascular interleukin-10 protects against LPS-induced vasomotor dysfunction

Area of Science:

• Immunology
• Vascular Biology
• Pharmacology

Background:

• Lipopolysaccharide (LPS) induces vascular dysfunction, characterized by impaired arterial relaxation.
• Interleukin-10 (IL-10) is a key anti-inflammatory cytokine with potential protective roles in vascular inflammation.
• Inducible nitric oxide synthase (iNOS) is implicated in inflammatory responses and vascular dysfunction.

Purpose of the Study:

• To investigate the protective effects of systemic and local IL-10 against LPS-induced arterial dysfunction.
• To determine if IL-10 mitigates vascular dysfunction mediated by iNOS following LPS exposure.
• To assess the role of IL-10 in regulating superoxide levels in arteries after LPS challenge.

Main Methods:

• Adenoviral gene transfer was used to deliver IL-10 systemically and locally in IL-10-deficient and wild-type mice.
• Vascular reactivity to acetylcholine was measured in isolated arteries ex vivo.
• Superoxide levels and the role of iNOS (using aminoguanidine and iNOS-deficient mice) were assessed.

Main Results:

• Systemic and local IL-10 gene transfer improved arterial relaxation impaired by LPS.
• LPS increased arterial superoxide levels, which were reduced by IL-10 gene transfer.
• Inhibition of iNOS or absence of iNOS protected against LPS-induced vasomotor dysfunction.

Conclusions:

• Both systemic and local IL-10 protect arteries against LPS-induced inflammatory damage.
• IL-10 reduces vascular dysfunction by decreasing iNOS-mediated impairment of vasorelaxation.
• IL-10 also mitigates LPS-induced increases in arterial superoxide levels.