Role of Wnt/β-catenin signaling pathway in the mechanism of calcification of aortic valve

Abstract

Aortic valve calcification is a common disease in the elderly, but its cellular and molecular mechanisms are not clear. In order to verify the hypothesis that Wnt/β-catenin signaling pathway is involved in the process of calcification of aortic valve, porcine aortic valve interstitial cells (VICs) were isolated, cultured and stimulated with oxidized low density lipoprotein (ox-LDL) for 48 h to induce the differentiation of VICs into osteoblast-like cells. The key proteins and genes of Wnt/β-catenin signaling pathway, such as glycogen synthase kinase 3β (GSK-3β) and β-catenin, were detected by using Western blotting and real-time polymerase chain reaction (PCR). The results showed that the VICs managed to differentiate into osteoblast-like cells after the stimulation with ox-LDL and the levels of proteins and genes of GSK-3β and β-catenin were increased significantly in VICs after stimulation for 48 h (P<0.05). It is suggested that Wnt/β-catenin signaling pathway may play a key role in the differentiation of VICs into osteoblast-like cells and make great contribution to aortic valve calcification.

Keywords

aortic valve calcification / valve interstitial cells / Wnt/β-catenin signaling pathway / glycogen synthase kinase 3β / β-catenin

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