Innate Immune System Regulated by Stimulator of Interferon Genes, a Cytosolic DNA Sensor, Regulates Endothelial...

Area of Science:

• Immunology
• Cardiovascular Biology
• Metabolic Disorders

Background:

• Metabolic disorders, such as hyperglycemia, induce sterile inflammation that impairs endothelial function.
• The precise mechanisms by which hyperglycemia triggers inflammation and endothelial dysfunction are not fully understood.
• Stimulator of interferon genes (STING), a cytosolic DNA sensor, is implicated in inflammatory disease pathogenesis.

Purpose of the Study:

• To investigate the role of STING in endothelial dysfunction associated with streptozotocin-induced diabetes.
• To explore STING signaling as a potential therapeutic target for hyperglycemia-related endothelial dysfunction.

Main Methods:

• Streptozotocin (STZ) was used to induce diabetes in wild-type and STING-deficient mice.
• Vascular function was assessed by measuring responses to acetylcholine and sodium nitroprusside.
• STING activation was studied in vitro using human umbilical vein endothelial cells treated with STING agonists (cyclic GMP-AMP, mitochondrial DNA) and inhibitors (C-176).

Main Results:

• STZ injection increased STING expression and DNA damage markers in mouse aortas.
• Genetic deletion of STING or treatment with a STING inhibitor (C-176) ameliorated endothelial dysfunction in diabetic mice.
• STING activation in vitro increased inflammatory markers and impaired endothelial nitric oxide synthase phosphorylation.

Conclusions:

• The DNA damage response pathway mediated by STING plays a critical role in hyperglycemia-induced endothelial dysfunction.
• Targeting STING signaling offers a promising therapeutic strategy for managing endothelial dysfunction in diabetic conditions.