Natural regulatory T cells control coronary arteriolar endothelial dysfunction in hypertensive mice

Area of Science:

• Cardiovascular Biology
• Immunology
• Hypertension Research

Background:

• Hypertension significantly increases the risk of coronary artery disease and cardiovascular complications.
• The underlying cellular and molecular mechanisms of hypertension-related cardiovascular pathology are not fully understood.
• Immune cells and inflammation are increasingly recognized as key players in cardiovascular disease pathogenesis.

Purpose of the Study:

• To investigate the role of CD4(+)CD25(+) regulatory T cells (Tregs) in coronary arteriolar endothelial dysfunction in angiotensin II-dependent hypertensive mice.
• To elucidate the impact of Tregs on inflammation and vascular function in the context of hypertension.

Main Methods:

• Induction of hypertension in mice using angiotensin II infusion.
• Measurement of blood pressure via telemetry and Treg apoptosis using flow cytometry.
• Assessment of inflammation (macrophage activation/infiltration, TNF-α release) and coronary arteriolar endothelial function using an arteriograph.
• Therapeutic intervention by injecting Tregs into hypertensive mice.

Main Results:

• Angiotensin II infusion led to increased blood pressure, elevated Treg apoptosis, and significant inflammation (macrophage infiltration, TNF-α release).
• Hypertensive mice exhibited impaired coronary arteriolar endothelial-dependent relaxation.
• Administration of Tregs to hypertensive mice reduced inflammation and significantly improved endothelial function.

Conclusions:

• Regulatory T cells (Tregs) play a critical protective role in preventing coronary arteriolar endothelial dysfunction in hypertension.
• Tregs modulate inflammatory responses, including macrophage activation and TNF-α release, in the hypertensive vasculature.
• These findings highlight Tregs as a potential therapeutic target for vascular complications associated with hypertension.