What is endothelial dysfunction?

Endothelial dysfunction is a condition in which the endothelium, the thin layer of cells that lines the inside of blood vessels, does not function properly. The endothelium plays a crucial role in regulating blood flow, blood pressure, and inflammation in the body. When endothelial function is impaired, it can lead to various cardiovascular diseases, including atherosclerosis, coronary artery disease, and heart failure.

Here are some of the key features of endothelial dysfunction:

1. Impaired vasodilation: The endothelium releases substances such as nitric oxide (NO) that cause blood vessels to relax and widen, a process known as vasodilation. In endothelial dysfunction, the production or release of NO is decreased, leading to impaired vasodilation and increased resistance to blood flow.

2. Increased inflammation: The endothelium plays a crucial role in regulating the inflammatory response within the blood vessels. Endothelial dysfunction can lead to chronic inflammation, characterized by an increased production of pro-inflammatory molecules and decreased production of anti-inflammatory molecules.

3. Increased oxidative stress: Endothelial dysfunction is often associated with increased oxidative stress, an imbalance between the production of reactive oxygen species (ROS) and the body's antioxidant defense systems. Oxidative stress can damage endothelial cells and contribute to the development of endothelial dysfunction.

4. Increased thrombosis: Endothelial dysfunction impairs the antithrombotic properties of the endothelium, leading to an increased risk of blood clot formation (thrombosis). The endothelium normally releases substances that prevent platelet aggregation and promote the breakdown of blood clots. In endothelial dysfunction, these protective mechanisms are impaired.

5. Impaired angiogenesis: Angiogenesis, the process of forming new blood vessels, is essential for tissue growth, repair, and recovery. Endothelial dysfunction can impair angiogenesis, leading to insufficient blood supply to tissues and organs.

Endothelial dysfunction is commonly associated with risk factors such as high blood pressure, high cholesterol, diabetes, smoking, obesity, and physical inactivity. It is also influenced by genetic factors and certain medical conditions. Assessing and addressing endothelial dysfunction is an important aspect of preventing and managing cardiovascular diseases.