GATA4 protects against hyperglycemia‑induced endothelial dysfunction by regulating NOX4 transcription

Area of Science:

• Cardiovascular Biology
• Molecular Medicine
• Diabetes Complications

Background:

• Endothelial dysfunction is a key complication of diabetes, contributing to atherosclerosis.
• The role of NADPH oxidase 4 (NOX4) in endothelial dysfunction is complex, with both cytotoxic and protective effects reported.
• Understanding the regulation of NOX4 is crucial for developing therapeutic strategies against diabetic vascular complications.

Purpose of the Study:

• To identify the transcription factor regulating NOX4 expression.
• To investigate the role of GATA-binding protein 4 (GATA4) in diabetes-induced endothelial dysfunction.
• To explore GATA4 as a potential therapeutic target for preserving endothelial function in diabetes.

Main Methods:

• Transcription factor activation profiling plate array and chromatin immunoprecipitation were used to identify NOX4 regulators.
• GATA4 expression and its effects on NOX4, nitric oxide (NO) production, and endothelial function were assessed in hyperglycemic human umbilical vein endothelial cells (HUVECs) and a mouse diabetes model.
• The impact of simvastatin on GATA4 expression and endothelial function was evaluated.

Main Results:

• GATA-binding protein 4 (GATA4) was identified as a mediator of NOX4 transcription.
• GATA4 expression was downregulated in hyperglycemic HUVECs and in endothelial cells from a mouse diabetes model.
• GATA4 overexpression increased NOX4 expression and nitric oxide (NO) production via endothelial NO synthase (eNOS) phosphorylation.
• Simvastatin treatment upregulated GATA4 expression, improving endothelial function in hyperglycemic HUVECs.

Conclusions:

• GATA4 acts as a transcription factor for NOX4, inhibiting diabetes-induced endothelial dysfunction.
• GATA4 enhances endothelial function by increasing NO production.
• GATA4 represents a novel molecular target for treating endothelial dysfunction in diabetes.