Valve Endothelial Cell Exposure to High Levels of Flow Oscillations Exacerbates Valve Interstitial Cell Calcification

Area of Science:

• Cardiovascular Biology
• Biomedical Engineering
• Cellular Mechanotransduction

Background:

• Aortic valve calcification involves paracrine signaling between valve endothelial cells (VECs) and valve interstitial cells (VICs).
• Hemodynamic stimuli, particularly flow abnormalities, can induce VEC dysfunction, altering VIC phenotype and promoting calcification.
• The precise relationship between VEC-exposed flow oscillations and VIC-mediated aortic valve calcification progression is not fully understood.

Purpose of the Study:

• To investigate the impact of quantified flow oscillations on VECs and subsequent VIC-induced calcification.
• To correlate in vitro findings with in vivo observations of aortic valve calcification patterns.

Main Methods:

• Quantification of flow oscillations experienced by VECs in a dynamic culture system.
• Incubation of VICs with VEC-conditioned media under varying flow oscillation conditions.
• Computational correlation of flow oscillation levels to specific aortic valve regions associated with calcification.

Main Results:

• VIC-induced calcification was significantly augmented under maximum flow oscillations (bidirectional flow).
• Maximum flow oscillations mimicked conditions where flow is forward for half the cycle and reversed for the other half.
• Computational analysis linked high flow oscillation regions to areas of severe calcified deposits in the aortic valve.

Conclusions:

• Specific patterns of flow oscillations experienced by VECs directly influence VIC-driven aortic valve calcification.
• Findings identify regions of the aortic valve susceptible to calcification based on flow dynamics.
• Establishes a foundation for engineering calcified valve tissues and developing novel therapeutic strategies for aortic valve calcification.