Endothelial dysfunction: a multifaceted disorder (The Wiggers Award Lecture)

Area of Science:

• Vascular Biology and Medicine
• Cardiovascular Pathophysiology

Background:

• Endothelial cells are crucial for regulating vascular homeostasis, including angiogenesis, inflammation, and tone.
• Endothelial dysfunction is implicated in numerous pathophysiological conditions, particularly cardiovascular diseases.
• Oxidative stress is a recognized common factor contributing to endothelial dysfunction.

Purpose of the Study:

• To elucidate the multifaceted mechanisms underlying endothelial dysfunction.
• To explore the variability in these mechanisms based on specific pathologies and influencing factors.
• To assess the efficacy of therapeutic interventions in restoring endothelial function.

Main Methods:

• Review and synthesis of existing literature on endothelial cell function and dysfunction.
• Analysis of factors contributing to endothelial dysfunction, including nitric oxide bioavailability, prostanoid production, and endothelin-1 release.
• Evaluation of the impact of various pathological conditions and co-existing factors (e.g., age, metabolic status) on endothelial function.

Main Results:

• Endothelial dysfunction involves diverse mechanisms, including reduced nitric oxide (NO) bioavailability, altered prostanoid synthesis (prostacyclin, thromboxane A2, isoprostanes), impaired endothelium-dependent hyperpolarization, and increased endothelin-1 release.
• The specific mechanisms and their contribution vary significantly depending on the disease context, vascular bed, and individual patient factors.
• Current therapeutic strategies often fail to completely reverse endothelial dysfunction, potentially improving only certain aspects.

Conclusions:

• Endothelial dysfunction is a complex syndrome with multiple contributing pathways that are highly context-dependent.
• Understanding these diverse mechanisms is critical for developing effective therapeutic strategies for cardiovascular diseases.
• Further research is needed to address the partial efficacy of current treatments and to fully restore endothelial function.