Dysregulation of ossification-related miRNAs in circulating osteogenic progenitor cells obtained from patients with aortic stenosis

Abstract

CAVD (calcific aortic valve disease) is the defining feature of AS (aortic stenosis). The present study aimed to determine whether expression of ossification-related miRNAs is related to differentiation intro COPCs (circulating osteogenic progenitor cells) in patients with CAVD. The present study included 46 patients with AS and 46 controls. Twenty-nine patients underwent surgical AVR (aortic valve replacement) and 17 underwent TAVI (transcatheter aortic valve implantation). The number of COPCs was higher in the AS group than in the controls (P<0.01). Levels of miR-30c were higher in the AS group than in the controls (P<0.01), whereas levels of miR-106a, miR-148a, miR-204, miR-211, miR-31 and miR-424 were lower in the AS group than in the controls (P<0.01). The number of COPCs and levels of osteocalcin protein in COPCs were positively correlated with levels of miR-30a and negatively correlated with levels of the remaining miRNAs (all P<0.05). The degree of aortic valve calcification was weakly positively correlated with the number of COPCs and miR-30c levels. The number of COPCs and miR-30c levels were decreased after surgery, whereas levels of the remaining miRNAs were increased (all P<0.05). Changes in these levels were greater after AVR than after TAVI (all P<0.05). In vitro study using cultured peripheral blood mononuclear cells transfected with each ossification-related miRNA showed that these miRNAs controlled levels of osteocalcin protein. In conclusion, dysregulation of ossification-related miRNAs may be related to the differentiation into COPCs and may play a significant role in the pathogenesis of CAVD.

Keywords: aortic valve replacement; calcific aortic valve disease; calcification; osteocalcin; transcatheter aortic valve implantation.

Figure 1. Representative cases of multidetector computed tomography in patients with severe AVC (A) and moderate AVC (B)

(A) Echocardiographic findings showed an aortic valve area of 0.68 cm² and mean aortic gradient of 45 mmHg. (B) Echocardiographic findings showed an aortic valve area of 0.77 cm² and mean aortic gradient of 53 mmHg.

Figure 2. Levels of ossification-related miRNAs (A) and osteocalcin MFI (B) in AS group and controls

*P<0.01 compared with controls.

Figure 3. Changes in numbers of COPCs (A) and osteocalcin MFI (B) in AVR and TAVI groups

*P<0.01 compared with TAVI group.

Figure 4. Changes in ossification-related miRNAs in AVR and TAVI groups

*P<0.01 compared with controls.

Figure 5. Levels of ossification-related miRNAs and osteocalcin in PBMCs transfected with ossification-related miRNA mimic and inhibitor

(A) Comparison of ossification-related miRNA levels between PBMCs transfected with ossification-related miRNA mimic and inhibitor. (B) Comparison of osteocalcin protein levels between PBMCs transfected with ossification-related miRNA mimic and inhibitor. *P<0.01 compared with mock.