Current opinion: Underreported cell populations in the aortic valve influence tissue development and homeostasis

Abstract

During valvulogenesis, various cells in the developing heart remodel the cushions in the outflow tract to shape the aortic valve (AoV). In adulthood, mature cells maintain the tissue in homeostatic balance to cope with changes in cardiac mechanics. Pathological progression of aortic valve disease is characterized by asymptomatic irreversible extracellular matrix (ECM) remodeling rendering the valve dysfunctional, ultimately leading to heart failure and death if the valve is not replaced. Resident cells within the tissue are responsible for congenital and acquired pathological conditions. A complex heterogenous population of cells resides within the valve apparatus, including underreported populations of neurons and melanocytes. Though not thoroughly explored, reports suggest that these cell types have implications in development, homeostasis, and disease progression within the AoV. In this current opinion piece, we summarize recent and relevant literature exploring the connection between both AoV cellular heterogeneity and cell developmental origin in development and disease.