Basic proteins in the human aortic intima: nonequilibrium two-dimensional electrophoretic analysis of tissue extracts

Area of Science:

• Biochemistry
• Cardiovascular Biology
• Proteomics

Background:

• Atherosclerosis involves changes in aortic intima protein composition.
• Understanding these changes is crucial for identifying atherogenesis mechanisms.

Purpose of the Study:

• To compare the protein profiles of atheroma-free human thoracic intima with those containing fatty streaks or fibro-fatty lesions.
• To identify proteins that may be involved in the development of atherosclerotic lesions.

Main Methods:

• Two-dimensional gel electrophoresis (2-DE), specifically nonequilibrium pH gradient electrophoresis (NEPHGE) followed by polyacrylamide gel electrophoresis (PAGE).
• Silver staining was used for protein visualization.
• Combined NEPHGE-PAGE and isoelectric focusing (ISO)-PAGE for enhanced protein detection.

Main Results:

• Identified major proteins in healthy intima, including actin, tropomyosin-like proteins, P250, P15a, P15b, myosin heavy and light chains, and others.
• Observed additional proteins in intimas with fatty streaks and fibro-fatty lesions, predominantly plasma-derived proteins like albumin, transferrin, Apo A-I, alpha 1-antitrypsin, fibrinogen beta-chain, and IgG.
• Protein composition differences between lesioned and non-lesioned intima varied individually.

Conclusions:

• The study identified distinct protein profiles in healthy versus atherosclerotic human thoracic intima.
• Plasma-derived proteins are significantly increased in atherosclerotic lesions, indicating a potential role in atherogenesis.
• Combined 2-DE techniques enhance the detection of intimal proteins, facilitating further study of their role in atherosclerosis.