Telomerase reverse transcriptase protects against angiotensin II-induced microvascular endothelial dysfunction.

Area of Science:

• Cardiovascular Physiology
• Molecular Biology
• Microcirculation Research

Background:

• Elevated reactive oxygen species (ROS) contribute to cardiovascular disease by reducing nitric oxide (NO) bioavailability.
• Microvascular dysfunction, characterized by increased ROS and reduced NO, is implicated in cardiovascular pathologies.
• The specific roles of telomerase subunits in microvascular function remain unclear.

Purpose of the Study:

• To investigate the impact of telomerase reverse transcriptase (TERT) and telomerase RNA component (TERC) on microvascular ROS production and vasodilation.
• To determine the influence of TERT and TERC on microvascular responses to angiotensin II (ANG II).

Main Methods:

• Genetic manipulation of TERT and TERC in mouse models.
• Measurement of reactive oxygen species (ROS) production in microvessels.
• Assessment of peak vasodilation in response to stimuli and ANG II.
• In vivo administration of ANG II to induce vascular stress.

Main Results:

• Genetic loss of TERT, but not TERC, promoted flow-induced ROS formation in microvessels.
• TERT knockout exacerbated ANG II-induced microvascular dysfunction, while TERT overexpression was protective.
• TERC deficiency did not significantly affect microvascular ROS or vasodilation.

Conclusions:

• Loss of TERT, not TERC, is a key factor in elevated microvascular ROS and reduced vasodilation.
• TERT plays a protective role in the microcirculation against vascular stress.
• TERT represents a novel therapeutic target for microvascular dysfunction in cardiovascular diseases.