Strain Magnitude-Dependent Calcific Marker Expression in Valvular and Vascular Cells

Abstract

Aortic valve disease and atherosclerosis tend to coexist in most patients with cardiovascular disease; however, the causes and mechanisms of disease development in heart valves are still not clearly understood. To understand the contributions of the magnitude of cyclic strain (5% hypotension, 10% physiological, and 15% hypertension) in calcification, we used a model system of tissue-engineered collagen gels containing human aortic smooth muscle cells and human aortic valvular interstitial cells, both isolated from noncalcific heart transplant tissue. The compacted collagen gels were cultured in osteogenic media for 3 weeks in a custom-designed bioreactor and all assessments were performed at the end of the culture period. The major finding of this study is that bone morphogenic protein (BMP)-2 and BMP-4 and transforming growth factor-β1 mRNA expression significantly changed in response to the magnitude of applied strain in valvular cells, while the lowest expression was observed for the representative physiological strain. On the other hand, mRNA expression in vascular cells did not vary in response to the magnitude of strain. Regarding BMP-2 and BMP-4 protein expression determined by immunostaining, trends were similar to mRNA expression in vascular and valvular cells, where only valvular cells showed a varied protein expression depending on the magnitude of the strain applied. Our results suggest that cellular differences exist between vascular and valvular cells in their response to altered levels of cyclic strain during calcification.

Valve Interstitial Cells: The Key to Understanding the Pathophysiology of Heart Valve Calcification

“…Osteogenic medium triggers calcification only in attached VIC monocultures; VEC inhibit calcification driven by osteogenic medium 68 Ferdous, 2013 Human Long-term (3 w) cyclic stretch using a proprietary bioreactor for tubular molds Different stretch amplitudes are tested; 10% stretch was most procalcific. Arsenazo dye used for calcium.…”

Comparison of Mesenchymal Stem Cell Source Differentiation Toward Human Pediatric Aortic Valve Interstitial Cells within 3D Engineered Matrices

“…29 Cells were cultured in HAVIC growth medium (HGM) containing MCDB131 medium (Sigma), 10% fetal bovine serum (FBS; Invitrogen), 1% penicillin/streptomycin (P/ S; Invitrogen), 0.25 mg/L recombinant human fibroblast growth factor basic (rhbFGF; PeproTech), and 5 mg/L recombinant human epidermal growth factor (rhEGF; Invitrogen). 28,30,31 Cells were used at passages 4-8. Established primary human ADMSC and BMMSC were purchased from Lonza and cultured in stem cell growth medium (GM) containing DMEM/F12 medium (Invitrogen), 10% FBS, and 1% P/S.…”

In‐vitro analysis of early calcification in aortic valvular interstitial cells using Laser‐Induced Breakdown Spectroscopy (LIBS)

“…Early stage CAVD is associated with calcium (Ca) accumulation in aortic valves that can lead to stenotic aortic valves wherein extracellular matrix (ECM) decomposition and tissue stiffening occurs along with large nodule formation within the aortic valve cusps . CAVD is an active cell‐mediated condition, where the inhabitant valvular interstitial cells (VICs) differentiate into osteoblast‐like cells and exhibit bone‐like characteristics, such as calcific nodule formation , hydroxyapatite deposition and osteogenic marker expressions .…”