Excess Provisional Extracellular Matrix: A Common Factor in Bicuspid Aortic Valve Formation

Area of Science:

• Cardiovascular Research
• Developmental Biology
• Genetics

Background:

• Bicuspid aortic valve (BAV) is the most common congenital heart defect, affecting 0.5-2% of the population.
• BAV is linked to severe aortic stenosis and aortic aneurysms, with no current targeted therapeutics.
• Genetically modified mouse models are crucial for understanding BAV's molecular underpinnings.

Purpose of the Study:

• To investigate common molecular pathways in BAV development by comparing phenotypic characteristics across different murine models.
• To identify shared molecular features that could reveal therapeutic targets and biomarkers for BAV.

Main Methods:

• Comparative analysis of phenotypic characteristics in various genetically modified murine models of BAV.
• Collation and analysis of data on extracellular matrix composition, specifically versican levels.

Main Results:

• Excess versican within the provisional extracellular matrix (P-ECM) was identified as a common factor in BAV development across multiple murine models.
• Mutant mice, even those with low BAV incidence, showed altered tricuspid aortic valves with excess P-ECM compared to controls.

Conclusions:

• Common molecular characteristics, particularly excess versican in the P-ECM, are associated with BAV formation in mice.
• These findings suggest potential therapeutic targets and biomarkers for BAV, a prevalent and heterogeneous cardiovascular malformation.