Galectin-3 promotes calcification of human aortic valve interstitial cells via the NF-kappa B signaling pathway

Jingjing Luo; Shan Wang; Xing Liu; Qiang Zheng; Zhijie Wang; Yuming Huang; Jiawei Shi

doi:10.21037/cdt-21-506

Galectin-3 promotes calcification of human aortic valve interstitial cells via the NF-kappa B signaling pathway

Cardiovasc Diagn Ther. 2022 Apr;12(2):196-207. doi: 10.21037/cdt-21-506.

Authors

Jingjing Luo^#¹, Shan Wang^#², Xing Liu¹, Qiang Zheng¹, Zhijie Wang¹, Yuming Huang³, Jiawei Shi¹

Affiliations

¹ Department of Cardiovascular Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
² Department of Anesthesiology, Wuhan Children's Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
³ Department of Thoracic and Cardiovascular Surgery, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China.

^# Contributed equally.

Abstract

Background: Calcific aortic valve disease (CAVD) is an active pathobiological process that takes place at the cellular and molecular levels. It involves fibrosis and calcification of aortic valve leaflets, which eventually contributes to heart failure. Galectin-3 (Gal-3), a β-galactoside-binding lectin, is involved in myocardial fibrosis and remodeling. Our study aimed to explore how Gal-3 promoted the osteogenic differentiation of human aortic valve interstitial cells (hVICs) along with elucidating the underlying molecular mechanisms.

Methods: To determine the Gal-3 expression in this study, we included the blood samples and aortic valves (AVs) from patients with CAVD (n=20) and normal controls (n=20). The hVICs were stimulated by Osteogenic medium (OM) and were treated with or without recombinant human Gal-3. Calcified transformation of hVICs was assessed by Alizarin Red S staining and osteogenic gene/protein expression. RNA-sequencing was performed for all different treatments to investigate differentially expressed genes (DEGs) along with exploring the enriched pathways for potential molecular targets of Gal-3. The targets were further detected using Western blotting and immunofluorescence staining.

Results: Gal-3 levels were found to be significantly increased in CAVD patients. Treatment of valve interstitial cells (VICs) with Gal-3 led to a marked increase in Runx2 and ALP-mRNA/protein expression levels as well as calcification. Gene expression profiles of hVICs cultured with or without Gal-3 revealed 79 upregulated genes and 82 down-regulated genes, which were highly enriched in TNF and NF-κB signaling pathways. Furthermore, Gal-3 could activate the phosphorylation of IκBα and interfere with the translocation of p65 into the cell nucleus of hVICs. However, inhibition of this pathway can suppress the osteogenic differentiation by Gal-3.

Conclusions: Gal-3 acts as a positive regulator of osteogenic differentiation by activating the NF-κB signaling pathway in hVICs. Our findings provide novel mechanistic insights into the critical role of Gal-3 in the CAVD progression.

Keywords: Calcific aortic valve disease (CAVD); Galectin-3 (Gal-3); NF-kappa B pathway (NF-κB pathway); Osteogenesis; human aortic valve interstitial cells (hVICs).